RECLOSABLE PACKAGE INCLUDING SELF-MATING FASTENER AND PROCESS FOR MAKING THE SAME
A reclosable package and processes for making it are disclosed. The reclosable package includes a front panel, a back panel, an upper seal region adapted to be broken to allow a first opening of the reclosable package, a lower seal opposite the upper seal region, a vertical seal extending between the upper seal region and the lower seal on the back panel between the first side edge and the opposing second side edge; and a self-mating fastener disposed adjacent the upper seal region in an interior of the reclosable package. The self-mating fastener includes first and second fastener members each having fastener elements, an open configuration to allow access to the interior volume of the reclosable package, and a closed configuration in which the fastener elements of the first and second fastener members are engaged. In the closed configuration, the self-mating fastener is up to 800 micrometers thick.
This application claims priority to U.S. Provisional Application No. 62/855,307, filed May 31, 2019, the disclosure of which is incorporated by reference in its entirety herein.
BACKGROUNDFasteners are used in a variety of applications, including construction, machinery, medical equipment, automobile assembly, personal care products, and the textile industry. Commonly known fasteners range from rivets, snaps and buttons to hook and loop fasteners, each of which involve joining unlike components (e.g., male and female components) for assembling two articles together. Some fasteners, which are sometimes called self-mating fasteners or hook-and-hook fasteners, are composed of interlocking members that do not include male and female components. For assembling two articles together, each fastening member is attached to a surface of its respective article, and the two articles are joined together when the fastening members are mated.
Certain fasteners have been reported that include different structures on the same fastening member. See, for example, U.S. Pat. No. 5,586,372 (Eguchi); U.S. Pat. No. 5,884,374 (Clune); U.S. Pat. No. 6,276,032 (Nortman); and U.S. Pat. No. 6,546,604 (Galkiewicz). The different structures may have different shapes, sizes, or abilities to engage.
Reclosable packages can be used as containers for various consumer goods such as dry goods, food such as potato chips and cheese, animal food, lawncare products, etc. Such packages are available in a variety of shapes and sizes. Further, various reclosable packages can be multi-use containers that can maintain storage of consumer goods disposed within the packages for a desired number of openings and closings of the package. For example, a multi-use package can provide access by a user to the contents disposed within the package and then be closed to prevent the contents from spilling out of the package. These multi-use packages can include built-in fasteners that can be repeatedly opened and closed. Further, various multi-use packages can also be resealed after the first opening of the packages to keep the contents fresh and free from intrusion by various external elements such as air, moisture, and various contaminants.
Typically, reclosable packages can be made from one or more sheets or films that include one or more flexible materials. A film can be folded and sealed together to form a pouch having an interior volume and an opening through which consumer goods can be disposed within the volume. A fastener can be disposed adjacent the opening that can be repeatedly manipulated from a closed configuration to an open configuration.
Some reclosable packages having self-mating fasteners have been reported. See, for example, U.S. Pat. No. 8,641,278 (Ducauchuis) and U.S. Pat. Appl. Pub. Nos. 2006/0168776 (Dais) and 2013/0071047 (VanLoocke).
SUMMARYIn general, the present disclosure provides various embodiments of a reclosable package that includes a self-mating fastener and processes for making the reclosable package. The self-mating fastener can include an open configuration and a closed configuration. When in the open configuration, the self-mating fastener is adapted to allow access to an interior volume of the pouch through an opening disposed in the pouch after a first opening of the pouch. Further, when in the closed configuration, the first and second fastener members of the self-mated fastener are engaged together, and the self-mating fastener has a thickness of up to 800 micrometers.
In one aspect, the present disclosure provides the present disclosure provides a reclosable package that includes a front panel, a back panel opposite the front panel, an upper seal region at a top end of the resealable package, a lower seal at a bottom end of the resealable package, opposite the upper seal region, a vertical seal perpendicular to and extending between the upper seal region and the lower seal on the back panel, and a self-mating fastener disposed adjacent the upper seal region in an interior of the reclosable package. The upper seal region extends between a first side edge and an opposing second side edge and is adapted to be broken to allow a first opening of the reclosable package. The lower seal region extends between the first side edge and the opposing second side edge. The vertical seal is located between the first side edge and the opposing second side edge. The self-mating fastener includes first and second fastener members each having first major surfaces with fastener elements, an open configuration to allow access to the interior volume of the reclosable package, and a closed configuration in which the fastener elements of the first and second fastener members are engaged together. In the closed configuration, the self-mating fastener has a thickness of up to 800 micrometers.
In another aspect, the present disclosure provides a process for making the reclosable package. The process includes wrapping a film around a former to provide a tube of film. The film has first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edge, and a row of self-mated fastening strips in a central portion of the film not including the first or second longitudinal edges. Each of the self-mated fastening strips extends perpendicular to the first and second longitudinal edges of the film and includes first and second fastener members each having first major surfaces with fastener elements engaged together, a length up to fifty percent of the distance between the first and second opposing longitudinal edges, and a thickness of up to 800 micrometers. The second major surface of the first fastener member is attached to the film, and the second major surface of the second fastener member is exposed to an interior of the tube of film. The process further includes bringing together the first and second longitudinal edges of the film, sealing the first and second longitudinal edges together to form a vertical seal, and attaching the second major surface of the second fastener member to the film over the vertical seal.
In another aspect, the present disclosure provides a process for making the reclosable package. The process includes wrapping a film around a former to provide a tube of film. The film includes first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of fastening strips extending perpendicularly to the first and second longitudinal edges. Each of the fastening strips includes a first major surfaces with fastener elements exposed to an interior of the tube of film, a second major surface attached to the film, and a thickness of up to 800 micrometers. The process further includes bringing the first and second longitudinal edges into contact; and sealing the first and second longitudinal edges together to form a vertical seal.
All headings provided herein are for the convenience of the reader and should not be used to limit the meaning of any text that follows the heading, unless so specified.
The term “comprises” and variations thereof do not have a limiting meaning where these terms appear in the description and claims. Such terms will be understood to imply the inclusion of a stated step or element or group of steps or elements but not the exclusion of any other step or element or group of steps or elements.
Terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terms “a”, “an”, and “the” are used interchangeably with the term “at least one”.
The phrase “comprises at least one of” followed by a list refers to comprising any one of the items in the list and any combination of two or more items in the list. The phrase “at least one of” followed by a list refers to any one of the items in the list or any combination of two or more items in the list.
As used herein, the term “or” is generally employed in its usual sense including “and/or” unless the content clearly dictates otherwise.
The term “and/or” means one or all of the listed elements or a combination of any two or more of the listed elements.
The term “machine direction” (MD) as used herein denotes the direction of a running web of material during a manufacturing process. When a strip is cut from a continuous web, the dimension in the machine direction corresponds to the length “L” of the strip. The terms “machine direction” and “longitudinal direction” may be used interchangeably. The term “cross-machine direction” (CD) as used herein denotes the direction which is essentially perpendicular to the machine direction. When a strip is cut from a continuous web, the dimension in the cross-machine direction corresponds to the width “W” of the strip. Accordingly, the term “width” typically refers to the shorter dimension in the plane of the first surface of the backing, which is the surface bearing the rail segments and posts. As used herein the term “thickness” usually refers to the smallest dimension of the fastener, which is the dimension perpendicular to the first surface of the backing.
The term “alternating” as used herein refers, for example, to one row of rail segments being disposed between any two adjacent rows of posts (i.e., the rows of posts have only one row of rail segments between them) and one row of posts being disposed between any two adjacent rows of rail segments and/or one row of rail segments being disposed between any two adjacent ribs (i.e., the adjacent ribs have only one row of rail segments between them) and one rib being disposed between any two adjacent rows of rail segments.
The term “fastener element” includes the various types of elements used herein in a self-mating fastener, for example, rail segments, posts, ribs, rails, and combinations thereof.
The term “perpendicular” as used herein to refer to the relationship between the backing and the fastener elements includes substantially perpendicular. “Substantially perpendicular” means that the planes defined by the backing and a row of rail segments or posts can deviate from perpendicular by up to 10 (in some embodiments, up to 7.5 or 5) degrees.
The term “continuous” with reference to the base portion of the rib is relative to the length of the rail segments, which are segmented and not continuous. The continuous base portion is continuous for the length of at least five rail segments. In some embodiments, the continuous base portion is continuous for the length of the backing.
As used herein in connection with a measured quantity, the term “about” refers to that variation in the measured quantity as would be expected by the skilled artisan making the measurement and exercising a level of care commensurate with the objective of the measurement and the precision of the measuring equipment used. Herein, “up to” a number (e.g., up to 50) includes the number (e.g., 50).
All numerical ranges are inclusive of their endpoints and nonintegral values between the endpoints unless otherwise stated (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).
These and other aspects of the present disclosure will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.
The disclosure may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings, in which:
As used herein, the term “allow access” means that a user of the reclosable package 100 can reach into the interior volume 122 of the pouch 120 through the opening 124 and grasp at least a portion of consumer goods disposed within the interior volume. Further, as used herein, the term “prevent access” means that the user of the reclosable package cannot reach into the interior volume 122 of the pouch 120 through the opening 124 to grasp at least a portion of the consumer goods disposed within the interior volume without first manipulating the self-mating fastener 150.
The pouch 120 can include any suitable bag or package that defines the interior volume 122. Further, the pouch 120 can be adapted to contain any suitable items. In some embodiments, the pouch 120 can be adapted to contain any suitable consumer goods, e.g., foodstuffs such as crackers, potato or corn chips, and cheese, bulk granular or powdered products, animal feed, lawn and garden products, etc.
The pouch 120 can be formed using any suitable technique or techniques. In the embodiments illustrated in
The pouch 120 can have any suitable dimensions and take any suitable shape or combination of shapes. Further, the pouch 120 includes a front panel 130 and a back panel 132. The front panel 130 and the back panel 132 can meet at the first and second side edges 134, 136. In some embodiments, the front panel 130 and the back panel 132 are integral such that the pouch 120 does not include seams or seal regions adjacent one or both of the first and second side edges 134, 136. As used herein, the term “adjacent the side edge” means that an element or component of the package 100 is disposed closer to one of the first and second side edges 134, 136 than to the rear seal region 138.
The pouch 120 can include the opening 124 (
In some embodiments, the pouch 120 can include a seal region disposed adjacent the opening 124 that is adapted to be broken to allow a first opening of the pouch such that the user can access consumer goods disposed within the interior volume 122. As used herein, the term “first opening” refers to the first time that the reclosable package is opened by the user following manufacturing and filling of the package.
In the embodiments illustrated in
The pouch 120 can be made using any suitable material or materials, e.g., one or more inorganic, polymeric, and metallic materials. In some embodiments, the pouch 120 can include one or more polymeric materials such as a polyolefin (e.g., oriented polypropylene OPP, low density polyethylene (LDPE), and linear low polyethylene (LLDPE)), a polyester (e.g., poly(ethylene terephthalate) (PET)), a polyacrylate, and ethylene vinyl alcohol (EVOH). Films of these materials are available as single-layer films, for example, and as multiple layer films including functional tie layers. Multiple layer films can be made by coextrusion or stepwise extrusion. The functional tie layer can be made of any of the polymeric materials described for the pouch blended with 5% by weight to 50% by weight of a functional polymer. The multiple layer film is usually configured with the tie layer on the inside of the pouch 120 and can allow for adhesive bonding and hermetic sealing of the pouch. Many functional polymers useful as tie layer resins are commercially available, for example, from Dow Chemical Company under the trade designation “AMPLIFY”. In some embodiments, the pouch 120 can include a flexible material. Tie layers on the pouch may also include any of the elastomeric materials described below in connection with the tie layer on the fastener.
The pouch 120 can include any suitable graphic or graphics (not shown) disposed on one or both of the front and back panels 130, 132 using any suitable technique or techniques, e.g., ink jet printing, laminating, digital printing, flexographic printing, screen printing, ink transfer, and combinations of these. In some embodiments, the graphic (not shown) can be disposed on the front panel of the pouch, where a portion of the graphic is disposed over the self-mating fastener 150 when the fastener is in the closed configuration.
Connected to the pouch 120 is the self-mating fastener 150 as described below in any of its embodiments. The self-mating fastener 150 can be connected to the pouch 120 in any suitable location. In the embodiment illustrated in
Further, the self-mating fastener 150 of the present disclosure can be disposed in any suitable location relative to the opening 124 of the pouch 120 such that the fastener when in the open configuration can allow access to the interior volume 122 of the pouch through the opening, after the upper seal region 140 has been broken and that when in the closed configuration the fastener is adapted to prevent access to the interior volume of the pouch through the opening.
For example, as shown in
The self-mating fastener 150 can have any suitable dimensions and take any suitable shape or shapes. In some embodiments, the self-mating fastener 150 can be connected to the pouch 120 adjacent the top edge 126 of the pouch and extend between the first and second side edges 134, 136 of the pouch as shown in
As shown in
In some embodiments, the first fastener member 152 can overlap with the second fastener member 154 in a direction orthogonal to the front and back panels 130, 132 such that at least a portion of the first fastener member can mate with the second fastener member. In some embodiments, the first fastener member 152 is registered with the second fastener member 154 in the direction orthogonal to the front and back panels 130, 132 as shown, e.g., in
The self-mating fastener 150 can be connected to the pouch 120 using any suitable technique or techniques. In some embodiments, the fastener 150 is adhered to the pouch 120 using any suitable adhesive or combination of adhesives, including any of the hot melt adhesives described herein. In some embodiments, the first fastener member is adhered to the front panel 130 with a pressure sensitive adhesive. Further, in some embodiments, self-mating fastener 150 can be ultrasonically bonded to the pouch 120. In some embodiments, the fastener 150 can be mechanically attached to the pouch 120 using any suitable technique or techniques. In some embodiments, a tie layer as described herein in any of its embodiments may be disposed between one or both of the first and second fastener members 152, 154 and the front and back panels 130, 132 respectively.
As mentioned herein, the self-mating fastener 150 has an open configuration and a closed configuration. For example, as shown in
In some embodiments of the process for making a reclosable package according to the present disclosure, the self-mating fastener 150 can be connected to the pouch 120 such that the fastener is in this closed configuration when the bag is manufactured. In some embodiments of the process for making a reclosable package according to the present disclosure, self-mating fastener 150 can be connected to the pouch 120 during manufacturing such that it is in an open configuration.
In embodiments where the self-mating fastener 150 is connected to the pouch 120 such that it is in the open configuration prior to the first opening of the pouch 120, the user may grasp portions of the front and back panels 130, 132 and manipulate the panels in a direction away from each other. During this manipulation by the user, the upper seal region 140 may remain intact while portions of the self-mating fastener 50 may be separated such that it is in the open configuration. In some embodiments, manipulation by the user upon the first opening of the pouch 120 may instead first separate the upper seal region 140 such that the seal region is at least partially broken prior to manipulation of the self-mating fastener 150 from the closed configuration to the open configuration.
Advantageously, the thickness of the self-mating fastener 150 in the closed configuration is also up to 800, 700, 600, 500, 450, or 400 micrometers when the first fastener member and the second fastener member do not share a unitary backing. Such a thickness can allow the self-mating fastener 150 to be self-mated when the bag is manufactured or otherwise not interfere with the vertical seal formation in some embodiments of the process for making the reclosable package according to the present disclosure. In some embodiments, the thickness of the self-mating fastener 150 in the closed configuration is at least 200, 250, 300, or 350 micrometers.
Any suitable technique or techniques may be utilized by the user to manipulate the self-mating fastener 150 to the closed configuration. For example, the user may press the self-mating closure 150 together by placing one hand on the front panel 130 and another hand on the back panel 132 and pressing the first fastener member 152 against the second fastener member 154. Further, for example, the user may place the package 100 on a flat surface such that either the first or second panels 130, 132 are in contact with the surface, and then press the first and second fastener members 152, 154 together.
When in the closed configuration as shown in
Any suitable technique or techniques can be utilized to determine whether the self-mating fastener 150 is in the closed configuration. For example, in some embodiments, the self-mating faster 150 is considered to be in the closed configuration when a force to open the self-mating fastener is at least about 0.1 Newtons and no greater than 1.0 Newtons as determined from the mean maximum load from the T-Peel Test Method described in the Examples. In some embodiments, the force to open the self-mating fastener is in a range 0.2 N to 0.9 N or 0.3 N to 0.8 N as determined from the mean maximum load from the T-Peel Test Method described in the Examples.
Further, in some embodiments, the force required to achieve a closed configuration from an open configuration, as previously defined, is no more than 3.0 Newtons (N) but at least 0.3 N as determined utilizing the Force to Close Test Method described in the Examples. In some embodiments, the force required to achieve a closed configuration from an open configuration is no more than 0.3 N/mm but at least 0.03 N/mm as determined utilizing the Force to Close Test Method. In some embodiments, the force required to achieve a closed configuration from an open configuration is in a range from 0.45 N to 2.7 N or 0.6 N to 2.4 N as determined utilizing the Force to Close Test Method. In some embodiments, transition from an open configuration to a closed configuration is readily achieved with finger pressure.
The self-mating fastener 150 and the material utilized for the pouch 120 can be selected to provide any desirable stiffness in resistance to bending about a pouch axis 102 that is perpendicular to a length 104 of the self-mating fastener as shown in
In some embodiments, each self-mated fastening strip 350 has an elongate form oriented perpendicular to the first longitudinal edge 338 and the second longitudinal edge 339 and is located in a central portion 346 of the film 300 not including the first or second longitudinal edges 338, 339. In general, the central portion 346 of the film 300 includes the geometric center between the first longitudinal edge 338 and the second longitudinal edge 339. The self-mated fastening strip 350 has a length 365 that is defined as the distance between the first end portion 356 and a second end portion 358. The first end portion 356 of the self-mated fastening strip is closer to the first longitudinal edge 338 than the second longitudinal edge 339 of the film 300, and the second end portion 358 of the self-mated fastening strip is closer to the second longitudinal edge 339 than the first longitudinal edge 338 of the film 300. In the illustrated embodiment, the length 365 of the self-mated fastening strip 350 is up to fifty percent of the distance 364 between the first and second opposing longitudinal edges 338, 339. In some embodiments, the length 365 of the self-mated fastening strip 350 is less than fifty percent or up to 49, 45, 40 or 35 percent of the distance 364 between the first and second opposing longitudinal edges 338, 339.
Film 300 can include a row of self-mated fastening strip 350, in which each self-mated fastening strip 350 is parallel with one another and separated by a generally uniform distance 363. Although film 300 depicts only two self-mated fastening strip 350, a typical film 300 useful in the process of making a reclosable package of the present disclosure may include substantially more self-mated fastening strips 350 each separated from one another by distance 363.
The self-mated fastening strips 350 can be connected to the film 300 using any suitable technique or techniques. In some embodiments, the self-mated fastening strips 350 are adhered to the film 300 using any suitable adhesive or combination of adhesives, including any of the hot melt adhesives described herein. The self-mated fastening strips 350 each include first and second fastener members 152, 154 as shown in
When tie layers or hot melt adhesives are used to connect the self-mated fastening strips 350 of to the film 300, heating the adhesive or tie layer can be carried out using high-temperature impingement fluid as described in U.S. Pat. No. 9,096,960 (Biegler et al.), U.S. Pat. No. 9,126,224 (Biegler et al.), and U.S. Pat. No. 8,956,496 (Biegler et al.). In some embodiments, the high-temperature fluid is a high-temperature gas (e.g., air, dehumidified air, nitrogen, an inert gas, a mixture of any of these, or another gas mixture). In some embodiments, the high-temperature fluid is high-temperature air. The high-temperature fluid can be directed toward the tie layer or hot melt adhesive only, or the high-temperature fluid can be directed toward both the tie layer or hot melt adhesive and the film 300 useful for forming the pouch. In some embodiments, high-temperature air is directed toward the tie layer or hot melt adhesive only before it is bonded to the film 300. In some embodiments, connecting the self-mated fastening strips 350 to the pouch 300 includes impinging high-temperature fluid, including any of those described above, onto a second surface of a web of the self-mating fastener while it is moving, wherein the second surface is the surface opposite the first surface bearing the fastening elements. In some of these embodiments, the second surface of the web includes a tie layer. In some embodiments, the second surface of the web includes a hot melt adhesive. Optionally, either sequentially or simultaneously, connecting the self-mated fastening strips 350 to the film 300 includes impinging high-temperature fluid, including any of those described above, onto a surface of a web of a film 300 useful for forming the pouch while the web of the film 300 is moving. Connecting the self-mated fastening strips 350 to the film can then be carried out by contacting the second surface of the first fastener member to the web of the film 300. A heated bar may also be useful for connecting the self-mated fastening strips 350 to the film 300. The self-mated fastening strips 350, tie layer, and/or hot melt adhesive may be contacted with a heated bar one or multiple times to ensure a good bond to the film 300. Typically, the heated bar is contacted to the non-adhesive-containing side of the film 300.
The self-mated fastening strips 350 include first and second fastener members each having first major surfaces with fastener elements engaged together, that is, in the closed configuration described above. In some embodiments, the first fastener member 152 and the second fastener member 154 are formed from a unitary strip of material, folded over onto itself, as shown in
To form a resealable package 100 using film 300, the first longitudinal edge 338 and second longitudinal edge 339 are brought together to form tube-like shape. In the embodiments illustrated in
In some embodiments, the portion of film 300 between first longitudinal edge 338 and boundary line 316 is overlapped with the second longitudinal edge 339 to form vertical seal 138 as a lap seal. The distance between first longitudinal edge 338 and boundary line 316 may vary depending upon package dimensions but will coincide approximately with the width of the vertical seal 138 of the resultant package formed from film 300. In some embodiments, embodiments, the distance between first longitudinal edge 338 and boundary line 316 is between 1.27 and 2.54 centimeters. In addition to a lap seal, the vertical seal 138 can be made as a fin seal, pinch seal, or a combination of a lap seal and fin seal. In some of these embodiments, portions of the film between the first and second longitudinal edges 338 and 339 and boundary lines 316 on both edges of the film (not shown) would be reserved for forming a seal.
In some embodiments of the process for making a reclosable package of the present disclosure, the process further comprises forming a lower seal perpendicular to the vertical seal 138 to form a bottom edge 142 of the reclosable package 100, which typically forms an open-ended package. The process can include dispensing consumer goods into the reclosable package 100, which can be any of the consumer goods described herein. In some embodiments, the process further comprises forming an upper seal 140 in the reclosable package 100 perpendicular to the vertical seal 138. Typically, one of the self-mated fastening strips 350 is between the upper seal 140 and bottom seal 142 and closer to the upper seal 140. In some embodiments, an inert gas can be added to the package before an upper seal 140 is created. The completed reclosable package 100 may then be separated from film 300.
Reclosable packages of the present disclosure and/or made by a process of the present disclosure can be made by a vertical form, fill, and seal machine. An embodiment of a vertical form, fill, and seal machine useful in the process for making the reclosable package of the present disclosure is shown in
The depiction of vertical form, fill, and seal machine 400 in
Vertical form, fill, and seal machine 400 generally includes a forming collar 470 at least partially encompassing former 472. Attached to the outer surface of the former 472, downstream from the forming collar 470, is a vertical sealer 474. Further downstream is a transverse sealer 476. Vertical form, fill, and seal machine 400 may also include one more pull belts 478 aligned with former 472 to advance film 300 downstream along the body of former 472. The packaging film 300 is maintained on a roll 480 and fed through a series of tensioners 482 before receipt by the forming collar 470.
In the embodiment illustrated in
Film 300 attains a generally tubular shape as it is wrapped around former 472. Referring again to
Using the process of the present disclosure in which fastening strips are self-mated and have a length up to fifty percent of the distance between the first and second opposing longitudinal edges, self-mating fastener can be formed within the interior region 124 of resealable package 100 to span substantially the entire width of reclosable package 100 between the first and second side edges 134, 136 of the pouch as shown in
Referring again to
In some embodiments of the process of the present disclosure, sealing jaws 476 can be designed to form the upper seal 140 of the reclosable package at the same time that the second fastener member is attached to the film and any space between the edges of the fastener and the side edges of the package are sealed.
It has been reported in U.S. Pat. App. Pub. No. 2017/0233143 (Huebner), for example, that attempts to install a zipper like fastener using an apparatus such as that shown in
In the reclosable package of the present disclosure and the process for making the reclosable package, the self-mating fastener has a thickness of up to 800 (in some embodiments, up to 700, 600, 500, 450, or 400) micrometers when first and second fastener members each having first major surfaces with fastener elements are engaged together. This is referred to as the closed configuration in the reclosable package of the present disclosure. In some embodiments, the self-mating fastener has a thickness of at least 200 (in some embodiments, at least 250, 300, or 350) micrometers when first and second fastener members each having first major surfaces with fastener elements are engaged together. With a thickness of up to 800 micrometers, the self-mated fastening strip can be used in the processes of the present disclosure without interfering with the formation of the vertical seal 138. Even when the fastening strip is self-mated it is thin enough to allow the formation of stable rolls 480 of film useful for the process and flexible enough to withstand the path around the forming collar and former without coming off the film. The fastening strip is also thin enough that equipment including the forming collar and former that are configured to convert packaging film into a bag can be used without requiring adjustment because of presence of the fastener.
Since the self-mating fastener has a thickness of up to 800 (in some embodiments, up to 700, 600, 500, 450, or 400) micrometers when first and second fastener members each having first major surfaces with fastener elements are engaged together, some embodiments of the process of making the self-mating fastener according to the present disclosure include bringing together the first and second longitudinal edges and sealing the first and second longitudinal edges together with the first and second end portions of one of the fastening strips to form a vertical seal. This process can be carried out using the film 300 shown in
An embodiment of a fastener useful in the reclosable package of the present disclosure is shown in
The base portion 10 of the rail segment 4 has a length Y1 that is greater than the width X1 of the base portion 10. In some embodiments, the ratio of the length Y1 to the width X1 of the base portion 10 is at least about 1.5:1, 2:1, 3:1, 4:1, or 5:1, 10:1, or 15:1. The base portion 10 of the rail segment 4 may have a variety of cross-section shapes. For example, the cross-sectional shape of the base portion 10 may be a polygon (e.g., rectangle, hexagon, or octagon), or the cross-sectional shape of the base portion 10 may be curved (e.g., elliptical). The base portion 10 may taper from its base to its distal end. In this case and in the case of curved base portions, the ratio of the length Y1 to the width X1 of the base portion 10 is measured from the longest and the widest point. As shown in
For embodiments such as the embodiment illustrated in
In some embodiments, the rail segments 4 have a maximum height Z1 (above the backing 2) of up to 0.65 millimeter (mm), 0.6 mm, or 0.55 mm and, in some embodiments, a minimum height of at least 0.1 mm or 0.2 mm. The height Z1 of the rail segments 4 can be in a range from 0.3 mm to 0.65 mm, 0.3 mm to 0.6 mm, or 0.35 mm to 0.55 mm. The thickness Z7 of the cap portion 8 of rail segments 4 can be in a range from 0.03 mm to 0.2 mm, 0.04 mm to 0.15 mm, or 0.04 mm to 0.1 mm. In some embodiments, the base portions 10 of the rail segments 4 have a maximum width X1 of up to about 0.4 mm, 0.3 mm, or 0.2 mm and a minimum width of at least 0.05 mm, 0.1 mm, or 0.125 mm. Some useful widths X1 of the base portions 10 are in a range from 0.05 mm to 0.2 mm, 0.1 mm to 0.2 mm or 0.125 mm to 0.175 mm. Some useful cap widths X4 of the rail segments 4 are in a range from 0.1 mm to 0.75 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.45 mm, or 0.3 mm to 0.4 mm. Some useful cap overhang distances X6 of the rail segments 4 are in a range from 0.025 mm to 0.3 mm, 0.05 mm to 0.3 mm or 0.1 m to 0.25 mm. In some embodiments, the rail segments 4 have a maximum length Y1 of up to about 1.5 mm (in some embodiments, up to 1.25, 1.0, 0.9, or 0.8) mm and a minimum length Y1 of at least about 0.1 mm, 0.2 mm, 0.4 mm, or 0.5 mm. The length Y1 of the rail segments can be in a range from 0.1 mm to 1.5 mm, 0.2 mm to 1.0 mm, or 0.600 mm to 0.800 mm. Some useful cap overhang distances Y5 of the rail segments 4 in the length direction are in a range from 0.025 mm to 0.2 mm, 0.025 mm to 0.1 mm, or 0.04 mm to 0.075 mm. In some embodiments, the cap-to-cap distance Y3 in the direction parallel to the length (L) of the fastener 1 is up to about 0.5 mm, 0.4 mm, 0.3 mm, or 0.25 mm and at least about 0.05 mm, 0.1 mm, or 0.125 mm. Some useful cap-to-cap distances Y3 are in a range from 0.05 mm to 0.5 mm, 0.1 mm to 0.3 mm, or 0.125 mm to 0.225 mm.
In some embodiments, the fastener useful for practicing the present disclosure comprises rows of posts. In the embodiment illustrated in
Posts useful in the fastener of the present disclosure may have a variety of cross-sectional shapes in a plane parallel to the backing. For example, the cross-sectional shape of the post may be a polygon (e.g., square, rectangle, rhombus, hexagon, pentagon, or dodecagon), which may be a regular polygon or not, or the cross-sectional shape of the post may be curved (e.g., round or elliptical). In some embodiments, the post has a base attached to the backing and a distal tip, and the distal tip has a cross-sectional area that is less than or equal to a cross-sectional area of the base. The post may taper from its base to its distal tip, but this is not a requirement. In some embodiments, the post has a distal cap with a cap width that is greater than the width of the base. The cap can overhang the base on opposing sides or may overhang the base on all sides. Capped posts useful in the fastener of the present disclosure can have a variety of useful shapes including a mushroom (e.g., with a circular or oval head enlarged with respect to the stem), a nail, a T, or a golf tee.
Referring again to
For embodiments such as the embodiment illustrated in
In some embodiments, the posts 6 have a maximum height Z3 (above the backing 2) of up to 0.6 millimeter (mm), 0.55 mm, or 0.5 mm and, in some embodiments, a minimum height of at least 0.08 mm or 0.16 mm. The height Z3 of the posts can be in a range from 0.2 mm to 0.6 mm, 0.3 mm to 0.5 mm, 0.3 mm to 0.4 mm, or 0.35 mm to 0.55 mm. In some embodiments, each of the posts has a height to width aspect ratio that is at least 1.5:1, at least 2:1, or at least 3:1. In some embodiments, each of the posts has a height to length aspect ratio that is at least 1.5:1, at least 2:1, or at least 3:1.
Another embodiment of a fastener useful in the reclosable package of the present disclosure and/or made by the method of the present disclosure is shown in
Another embodiment of a fastener useful in the reclosable package of the present disclosure and/or made by the method of the present disclosure is shown in
In some embodiments, ribs 26 useful in the fastener 21 shown in
Another embodiment of a fastener useful in the reclosable package of the present disclosure and/or made by the method of the present disclosure is shown in
Another embodiment of a fastener useful in the reclosable package of the present disclosure and/or made by the method of the present disclosure is shown in
In cross-section, fastener 41 can have the same appearance as fastener 1, illustrated in
Fasteners 1, 21, 31, and 41 are useful, for example, as self-mating fasteners. As used herein, self-mating refers to fasteners in which fastening is accomplished by interengaging fastening elements of the same type (e.g., fastening heads). In some embodiments, self-mating refers to fasteners in which fastening is accomplished by interengaging fastening elements of identical shape. In some embodiments, self-mating refers to the ability for the fastener to engage with itself when it is in a folded configuration, for example, along an axis parallel to either the length (L) or width (W) of the fastener, referring to
Since self-mating includes fasteners having fastening elements of the same type, any of the fasteners shown in
Referring again to
In some embodiments, the fastening system of the present disclosure is releasably fastenable. As used herein, the term “releasably fastenable” means that the fastener members can alternate between the fastened and unfastened configurations one or more times without destroying the functionality of the fastener. Typically and advantageously, the unique structure of the fastener of the present disclosure can allow for multiple cycles of fastening and unfastening without excessive plastic (i.e., irreversible) deformation of the engaging rail segments. As described in detail in the Examples, below, a comparative fastener that includes rail segments but no posts can undergo fastening when the rail segments are pushed against and past one another for interlocking. The cap portions of the rail segments of comparative fastener exhibit a relative high degree of plastic (i.e., irreversible) deformation after such engagement. The plastic deformation can limit the ability of the comparative fastener to be unfastened and refastened since the shape of the fastener is altered by the first and successive engagements. In contrast, in the fastening system of the present disclosure when the first and second fastener members undergo fastening, the posts undergo elastic deformation while the cap portions of the rail segments of the first and second fastener members pass by each other. The cap portions of the rail segments of the fastener of the present disclosure exhibit a relative low degree of plastic (i.e., irreversible) deformation after engagement.
Since fastener 1, 21, 31, 41 illustrated in
In some embodiments, when the first and second fastener members are fastened, they can slide relative to each other in a direction parallel to the length of the backing. This may be advantageous, for example, if the positioning of the first and second fastener members relative to each is not desirable when the first and second fastener members are initially fastened. To achieve a desirable positioning the first and second fastener members can be slid into place.
The first and second fastener members of a fastening system according to some embodiments of the present disclosure may or may not be connected together. In some embodiments, the first and second fastener members may be connected to two discrete substrates. In some embodiments, the first and second fastener members may be part of the same strip of material in which the first fastener member is folded over to contact the second fastener member.
In the fastener according to the present disclosure, the protruding rail segments, posts, ribs, and/or rails and at least a portion of the backing are integral (that is, generally formed at the same time as a unit, unitary). Fastening elements such as rail segments, upstanding posts, ribs, and rails on a backing can be made, for example, by feeding a thermoplastic material onto a continuously moving mold surface with cavities having the inverse shape of the fastening elements. The thermoplastic material can be passed between a nip formed by two rolls or a nip between a die face and roll surface, with at least one of the rolls having the cavities. Pressure provided by the nip forces the resin into the cavities. In some embodiments, a vacuum can be used to evacuate the cavities for easier filling of the cavities. The nip has a large enough gap such that a coherent backing is formed over the cavities. The backing may be formed with no holes therethrough. The mold surface and cavities can optionally be air or water cooled before stripping the integrally formed backing and fastening elements from the mold surface such as by a stripper roll.
Suitable mold surfaces for forming fastening elements on a backing include tool rolls such as those formed from a series of plates defining a plurality of cavities about its periphery including those described, for example, in U.S. Pat. No. 4,775,310 (Fischer). Cavities may be formed in the plates by drilling or photoresist technology, for example. Other suitable tool rolls may include wire-wrapped rolls, which are disclosed along with their method of manufacturing, for example, in U.S. Pat. No. 6,190,594 (Gorman et al.). Another example of a method for forming a backing with upstanding fastening elements includes using a flexible mold belt defining an array of fastening element-shaped cavities as described in U.S. Pat. No. 7,214,334 (Jens et al.). Yet other useful methods for forming a backing with upstanding fastening elements can be found in U.S. Pat. No. 6,287,665 U.S. Pat. No. (Hammer), U.S. Pat. No. 7,198,743 (Tuma), and 6,627,133 (Tuma).
Grooves 820a, 820b and higher-profile areas 840 can be formed in tool roll 810 using a variety of techniques. For example, grooves 820a, 820b and higher-profile areas 840 can be formed from a series of plates having different diameters that are stacked together to collectively form a tool roll or rings having different diameters that are stacked together and placed over a cylindrical base roll. Useful materials for making rings include stainless steel SS430, cold rolled steel, and copper. The cylindrical base roll or mandrel can be made out of aluminum wall, steel wall, or stainless steel wall and can be a water pressure vessel through which water can be passed for cooling and heating.
Tool roll 810 may also be a wire-wrapped roll, with wires helically wound around a base roll. Wire forming higher-profile area 840 has a higher profile than another wire, resulting in a tool roll 810 on which grooves 820 are formed between windings of the higher profile wire. Grooves 820 can also be machined into the surface of a metal master roll made, for example, of electroformed nickel or into screens formed into sleeves to fit over a cylindrical base roll.
In some embodiments, grooves 820a and 820b are provided with multiple protrusions 830. We have unexpectedly found that grooves that are up to 250 micrometers, in some embodiments, less than 250, up to 130, up to 110, up to 100, or up to 80 micrometers, in width and at least 250 micrometers, in some embodiments, at least 350, 400, 450, or 500 micrometers, in depth do not fill with moldable material when using a relatively low-pressure nip (e.g., less than 150 pounds per lineal inch (571 N/mm)). Instead, we found that only about 25 percent or 50 percent of the depth of the groove was filled even when increasing the pressure. We have further unexpectedly found when the grooves 820a and 820b are formed with multiple protrusion 830 around their peripheral surfaces, the grooves completely fill with moldable material, providing rails in the resulting film of the desired height and including notches 29 as shown in
We have found that the presence of ribs and rails having at least continuous base portions can improve the air sealing of the reclosable package of the present disclosure. Consumers may expect that a reclosable package should remain closed after the fastener is put into a closed configuration and also that the fastener should provide resistance to air flow across the fastener to maintain freshness of the consumer goods inside. If a consumer puts the fastener in a closed configuration is still able to squeeze the air out of the package or smell odor from the package, they may question the effectiveness of the fastener and recloseable bag. Inclusion of rails and ribs in the fastener useful for practicing the present disclosure improves the air sealing of the reclosable package when evaluated using the test method described in the Examples below. For example, in a comparison of Examples 6 and 8, replacement of a row of posts with a rib having at least a continuous base portion results in more than doubling the air pressure inside the bag introduced using a continuous stream of air.
Air sealing of the reclosable package may further be improved by the presence of adhesive (e.g., pressure sensitive adhesive) on at least a portion of the first major surface of the fastener members. In some embodiments, at least one of the first fastener member or the second fastener member comprises adhesive (e.g., pressure sensitive adhesive) on at least a portion of its first major surface. Pressure sensitive adhesives (PSAs) are well known to those of ordinary skill in the art to possess properties including the following: (1) aggressive and permanent tack, (2) adherence with no more than finger pressure, (3) sufficient ability to hold onto an adherend, and (4) sufficient cohesive strength to be cleanly removable from the adherend. Materials that have been found to function well as PSAs are polymers designed and formulated to exhibit the requisite viscoelastic properties resulting in a desired balance of tack, peel adhesion, and shear holding power.
One method useful for identifying pressure sensitive adhesives is the Dahlquist criterion. This criterion defines a pressure sensitive adhesive as an adhesive having a 1 second creep compliance of greater than 1×10−6 cm2/dyne as described in Handbook of Pressure Sensitive Adhesive Technology, Donatas Satas (Ed.), 2nd Edition, p. 172, Van Nostrand Reinhold, New York, N.Y., 1989. Alternatively, since modulus is, to a first approximation, the inverse of creep compliance, pressure sensitive adhesives may be defined as adhesives having a storage modulus of less than about 1×106 dynes/cm2.
A variety of PSAs may be useful on the first major surface of at least one of the first or second fastener member in the reclosable package of the present disclosure and/or on the second major surface of the first fastener member for attaching the first fastener member to film 300 as described above in connection with
If fastener elements formed upon exiting the cavities do not have caps, first and second fastener members will not have any closure affinity for each other. Caps can be subsequently formed on the rail segments and rails by a capping method as described in U.S. Pat. No. 5,077,870 (Melbye et al.). Typically, the capping method includes deforming the tip portions of the fastener elements using heat and/or pressure. The heat and pressure, if both are used, could be applied sequentially or simultaneously. The formation of rail segments and rails can also include a step in which the shape of the cap is changed, for example, as described in U.S. Pat. No. 6,132,660 (Kampfer) and/or U.S. Pat. No. 6,592,800 (Levitt). For example, one or more of these processes can be useful for changing the shape of the cap portion 8 shown in
Another useful method for fastener elements on a backing is profile extrusion described, for example, in U.S. Pat. No. 4,894,060 (Nestegard). Typically, in this method a thermoplastic flow stream is passed through a patterned die lip (e.g., cut by electron discharge machining) to form a web having downweb ridges, slicing the ridges, and stretching the web to form separated fastening elements. The ridges may be considered precursors to the fastening elements and exhibit the cross-sectional shape of the rail segments and posts to be formed. The ridges are transversely sliced at spaced locations along the extension of the ridges to form discrete portions of the ridges having lengths in the direction of the ridges essentially corresponding to the length of the fastener elements to be formed. Stretching the backing so that it plastically deforms results in the separation of the fastener elements.
Another self-mating fastener useful for practicing the present disclosure is described in copending U.S. Provisional Appl. No. 62/713,219 (Ausen et al.) filed Aug. 1, 2018.
The fastener of the present disclosure may be made from a variety of suitable materials, including thermoplastics. Examples of thermoplastic materials suitable for making the fastener using the methods described above include polyolefin homopolymers such as polyethylene and polypropylene, copolymers of ethylene, propylene and/or butylene; copolymers containing ethylene such as ethylene vinyl acetate and ethylene acrylic acid; polyesters such as poly(ethylene terephthalate), polyethylene butyrate, and polyethylene naphthalate; polyamides such as poly(hexamethylene adipamide); polyurethanes; polycarbonates; poly(vinyl alcohol); ketones such as polyetheretherketone; polyphenylene sulfide; and mixtures thereof In some embodiments, the thermoplastic useful for making the fastener comprises at least one of a polyolefin, a polyamide, or a polyester. In some embodiments, the thermoplastic useful for making the fastener is a polyolefin (e.g., polyethylene, polypropylene, polybutylene, ethylene copolymers, propylene copolymers, butylene copolymers, and copolymers and blends of these materials). In some embodiments, the fastener of the present disclosure is made from a blend of any of these thermoplastic materials and an elastomer. Examples of elastomers useful in such tie layers include elastomers such as ABA block copolymers (e.g., in which the A blocks are polystyrenic and formed predominantly of substituted (e.g., alkylated) or unsubstituted moieties and the B blocks are formed predominately from conjugated dienes (e.g., isoprene and 1,3-butadiene), which may be hydrogenated), polyurethane elastomers, polyolefin elastomers (e.g., metallocene polyolefin elastomers), olefin block copolymers, polyamide elastomers, ethylene vinyl acetate elastomers, and polyester elastomers. Examples of useful polyolefin elastomers include an ethylene propylene elastomer, an ethylene octene elastomer, an ethylene propylene diene elastomer, an ethylene propylene octene elastomer, polybutadiene, a butadiene copolymer, polybutene, or a combination thereof. Elastomers are available from a variety of commercial sources as described below. Any of these elastomers may be present in a blend with any of the thermoplastics in an amount of up to 20, 15, or 10 percent by weight.
The backing of the fastener of the present disclosure may have a variety of thicknesses. In some embodiments, including the embodiments illustrated in
In some embodiments, including the embodiments illustrated in
Rail segments and/or posts on the first surface of the backing may have a density of at least 10 per square centimeter (cm2) (63 per square inch in2). For example, the density of the rail segments may be at least 100/cm2 (635/in2), 248/cm2 (1600/in2), 394/cm2 (2500/in2), or 550/cm2 (3500/in2). In some embodiments, the density of the rail segments may be up to 1575/cm2 (10000/in2), up to about 1182/cm2 (7500/in2), or up to about 787/cm2 (5000/in2). Densities in a range from 10/cm2 (63/in2) to 1575/cm2 (10000/in2) or 100/cm2 (635/in2) to 1182/cm2 (7500/in2) may be useful, for example. The density of the rail segments is related to the distance between rail segments X7, measured as the center-to-center distance of the rail segments in adjacent rows as shown in
In some embodiments, the backing can be monoaxially or biaxially stretched. Stretching in the machine direction can be carried out on a continuous web of the backing, for example, by directing the web over rolls of increasing speed. Stretching in a cross-machine direction can be carried out on a continuous web using, for example, diverging rails or diverging disks. A versatile stretching method that allows for monoaxial and sequential biaxial stretching of the thermoplastic layer employs a flat film tenter apparatus. Such an apparatus grasps the thermoplastic layer using a plurality of clips, grippers, or other film edge-grasping means along opposing edges of the thermoplastic web in such a way that monoaxial and biaxial stretching in the desired direction is obtained by propelling the grasping means at varying speeds along divergent rails. Increasing clip speed in the machine direction generally results in machine-direction stretching. Stretching at angles to the machine direction and cross-direction are also possible with a flat film tenter apparatus. Monoaxial and biaxial stretching can also be accomplished, for example, by the methods and apparatus disclosed in U.S. Pat. No. 7,897,078 (Petersen et al.) and the references cited therein. Flat film tenter stretching apparatuses are commercially available, for example, from Brückner Maschinenbau GmbH, Siegsdorf, Germany.
In some embodiments, after stretching, the backing has an average thickness of up to 150 μm, 125 μm, 100 μm, 80 μm, or 75 μm. In some embodiments, the average thickness of the backing after stretching is in a range from 30 μm to 150 μm, 50 μm to 125 μm, or 50 μm to 100 μm. In general, the backing has no through-holes before or after stretching. In some embodiments, the density of the rail segments and/or posts after stretching may be up to about 1182/cm2 (7500/in2) or up to about 787/cm2 (5000/in2). Densities after stretching in a range from 2/cm2 (13/in2) to 1182/cm2 (7500/in2), 124/cm2 (800/in2) to 787/cm2 (5000/in2), 248/cm2 (1600/in2) to 550/cm2 (3500/in2), or 248/cm2 (1600/in2) to 394/cm2 (2500/in2) may be useful, for example. Again, the spacing of the spacing of the rows of rail segments and the posts need not be uniform.
In some embodiments, the backing includes a multi-layer construction. The multi-layer construction can include from 2 to 10, 2 to 5, or 2 to 3 layers. The multiple layers can include films, adhesives, and tie layers. The multiple layers can be joined together using a variety of methods including coating, adhesive bonding, and extrusion lamination. In some embodiments, the backing having the protruding fastening elements can be made (e.g., using any of the methods described above) from a multilayer melt stream of thermoplastic materials. This can result in the protruding fastening elements formed at least partially from a different thermoplastic material than the one predominately forming the backing. Various configurations of upstanding posts made from a multilayer melt stream are shown in U.S. Pat. No. 6,106,922 (Cejka et al.), for example. In some embodiments, the thickness of the backing (including a multi-layer backing) combined with the height of the rail segments is up to 800, 700, 650, 600, 500, 540, or 400 micrometers. In some embodiments, the thickness of the fastening system according to the present disclosure, in which the first and second fastener members are engaged with each other is up to 800, 750, 700, 650, 600, 500, 540, or 400 micrometers.
The bending stiffness of the fastener (e.g., at an axis parallel to the width of the fastener) is influenced by the modulus of the material or materials making up the backing, the thickness of the layer or layers making up the backing, the distance between the structures (including rail segments and posts) on the backing, and the dimension of the fastener in a parallel to the bending axis. In general, materials, thicknesses of the layer or layers in the fastener, and distances between structures can be selected to provide the fastener with a desirable bending stiffness. Advantageously, in many embodiments of the fastener of the present disclosure, the bending stiffness of the fastener is low enough such that the fastener does not unintentionally open when the fastener is bent. In some of these embodiments, the bending stiffness of the fastener in a closed configuration is in a range from 100 mN/mm to 1500 mN/mm, 200 mN/mm to 1200 mN/mm, or 300 mN/mm to 1000 mN/mm as measured by a Flexural Stiffness Test Method, for example, as described in the Examples, below.
In some embodiments, the fastener of the present disclosure and/or the backing of the fastener includes a tie layer. Tie layers can include elastomeric materials or other materials that have lower melting points than the backing integral with the fastening elements. Examples of elastomers useful in such tie layers include elastomers such as ABA block copolymers (e.g., in which the A blocks are polystyrenic and formed predominantly of substituted (e.g., alkylated) or unsubstituted moieties and the B blocks are formed predominately from conjugated dienes (e.g., isoprene and 1,3-butadiene), which may be hydrogenated), polyurethane elastomers, polyolefin elastomers (e.g., metallocene polyolefin elastomers), olefin block copolymers, polyamide elastomers, ethylene vinyl acetate elastomers, and polyester elastomers. Examples of useful polyolefin elastomers include an ethylene propylene elastomer, an ethylene octene elastomer, an ethylene propylene diene elastomer, an ethylene propylene octene elastomer, polybutadiene, a butadiene copolymer, polybutene, or a combination thereof. Various elastomeric polymers and other polymers may be blended to have varying degrees of elastomeric properties. For example, any of these elastomeric materials may be present in a range from 50% by weight to 95% by weight in a blend with any of the thermoplastics described above for forming the backing integral with the fastening elements.
Many types of elastomers are commercially available, including those from BASF, Florham Park, N.J., under the trade designation “STYROFLEX”, from Kraton Polymers, Houston, Tex., under the trade designation “KRATON”, from Dow Chemical, Midland, Mich., under the trade designation “PELLETHANE”, “INFUSE”, VERSIFY”, “NORDEL”, and “ENGAGE”, from DSM, Heerlen, Netherlands, under the trade designation “ARNITEL”, from E. I. duPont de Nemours and Company, Wilmington, Del., under the trade designation “HYTREL”, from ExxonMobil, Irving, Tex. under the trade designation “VISTAMAXX”, and more.
In some embodiments, the fastener of the present disclosure and/or the backing of the fastener includes a layer of a hot melt adhesive. Hot melt adhesives are typically non-tacky at room temperature, and use of hot melts can decrease contamination on equipment during the handling of the film and lamination. Suitable hot melt adhesives include those based on ethylene-vinyl acetate copolymers, ethylene-acrylate copolymers, polyolefins, polyamides, polyesters, polyurethanes, styrene block copolymers, polycaprolactone, and polycarbonates and may include a variety of tackifying resins, plasticizers, pigments, fillers, and stabilizers. Examples of suitable hot melt adhesives include those available from 3M Company, St. Paul, Minn., under the trade designation “3M SCOTCH-WELD” hot melt adhesives (e.g., products 3731 B and 3764 PG).
In some embodiments, the tie layer or hot melt adhesive will be thermally activated in a temperature range of 90° C. to 125° C. depending on time and pressure and can be useful for making a secure bond to a substrate, such as a film used in a reclosable package. Referring again to
While reclosable packages with fasteners have been reported, the fasteners can be stiff and bulky, making these packages difficult to manufacture and fill with consumer goods. Furthermore, fasteners than utilize hooks and loops can collect particles from the stored consumer goods or the environment outside of the package that contaminate the fastener. Such contamination can prevent the fastener from being completely closed, thereby allowing portions of the consumer goods to spill out of the package or prevent the package from preserving the freshness of the consumer goods.
In addition to the advantages of the reclosable package of the present disclosure and/or the process for making the reclosable package, various embodiments of the fastener can provide one or more advantages over other fasteners currently available for reclosable packages. For example, one or more embodiments of the fastener can have a reduced thickness compared to currently available fasteners such that the fastener can be connected to a packaging film used to form the package without compromising roll stability while also minimizing roll loss. As described above, the thickness of the fastener in which the first and second fastener members are engaged with each other is up to 800, 700, 600, 500, 450, or 400 micrometers. Also, as described above, in some embodiments, the fastener includes a tie layer or hot melt adhesive that can be thermally activated at relatively low temperature (e.g., 90 to 125° C.). In some embodiments, at least one of the thickness of the fastening system or the low-temperature activation of the tie layer can provide aesthetic advantages when the fastener is attached to a package. For example, any graphics on the package may have little or no distortion in the location of the fastener. Further, the fastener of the present disclosure can be more flexible than currently available fasteners such that the fastener does not unintentionally open if the fastener is bent, thereby preventing consumer goods disposed within the pouch from spilling out of the pouch. Further, one or more embodiments of the fastener of the present disclosure can be more contamination-resistant by preventing food debris such as small particles and salt from contaminating the fastener.
Some Embodiments of the DisclosureIn a first embodiment, the present disclosure provides a reclosable package comprising:
-
- a front panel;
- a back panel opposite the front panel;
an upper seal region at a top end of the resealable package, wherein the upper seal region extends between a first side edge and an opposing second side edge, and wherein the upper seal region is adapted to be broken to allow a first opening of the reclosable package;
-
- a lower seal at a bottom end of the resealable package, opposite the upper seal region, wherein the lower seal region extends between the first side edge and the opposing second side edge;
- a vertical seal perpendicular to and extending between the upper seal region and the lower seal on the back panel, wherein the vertical seal is located between the first side edge and the opposing second side edge; and
- a self-mating fastener disposed adjacent the upper seal region in an interior of the reclosable package, wherein the self-mating fastener comprises:
- first and second fastener members each having first major surfaces with fastener elements,
- an open configuration to allow access to the interior volume of the reclosable package, and
- a closed configuration in which the fastener elements of the first and second fastener members are engaged together, wherein in the closed configuration, the self-mating fastener has a thickness of up to 800 micrometers.
In a second embodiment, the present disclosure provides the reclosable package of the first embodiment, wherein at least one of the first fastener member or the second fastener member comprises a backing having a length, a width, and a thickness, with rows of rail segments protruding from the backing, wherein each of the rail segments has a base portion attached to the backing and a cap portion distal from the backing, wherein the cap portion has a cap width that is greater than a width of the base portion, wherein the cap portion overhangs the base portion on opposing sides, wherein the base portion has a length that is greater than the width of the base portion.
In a third embodiment, the present disclosure provides the reclosable package of the second embodiment, wherein a ratio of the length of the base portion to the width of the base portion of the rail segments is at least 2:1, 5:1, or 10:1.
In a fourth embodiment, the present disclosure provides the reclosabe package of the second or third embodiment, wherein the cap portion overhangs the base portion on all sides.
In a fifth embodiment, the present disclosure provides the reclosabe package of any one of the second to fourth embodiments, wherein the cap portion overhangs the base portion at amount of at least 25 micrometers on the opposing sides.
In a sixth embodiment, the present disclosure provides the reclosable package of any one of the second to fifth embodiments, wherein the at least one of the first fastener member or the second fastener member comprises rows of posts protruding perpendicularly from the backing, wherein the rows of rail segments and rows of posts alternate, and wherein each of the posts has a height that is no greater than a height of the rail segments.
In a seventh embodiment, the present disclosure provides the reclosable package of the sixth embodiment, wherein a number of posts in one of the rows of posts is more than a number of rail segments in one of the rows of rail segments.
In an eighth embodiment, the present disclosure provides the reclosable package of the sixth or seventh embodiment, wherein each of the posts has a length that is different from the length of the rail segments.
In a ninth embodiment, the present disclosure provides the reclosable package of any one of the sixth to eighth embodiments, wherein the length of the base portion of the rail segments is greater than a length of the posts.
In a tenth embodiment, the present disclosure provides the reclosable package of any one of the sixth to ninth embodiments, wherein the length of the base portion of the rail segments is at least two times or three times the length of the posts.
In an eleventh embodiment, the present disclosure provides the reclosable package of any one of the sixth to tenth embodiments, wherein the number of posts in one of the rows of posts is at least 1.5 or 2 times the number of rail segments in one of the rows of rail segments.
In a twelfth embodiment, the present disclosure provides the reclosable package of any one of the sixth to eleventh embodiments, wherein each of the posts has at least one of a height-to-width aspect ratio that is at least 1.5:1 or 2:1 or a height-to-length aspect ratio that is at least 1.5:1 or 2:1.
In a thirteenth embodiment, the present disclosure provides the reclosable package of any one of the sixth to twelfth embodiments, wherein the posts have a lower bending stiffness than the rail segments.
In a fourteenth embodiment, the present disclosure provides the reclosabe package of any one of the sixth to thirteenth embodiments, wherein the height of the posts is up to 95 percent of the height of the rail segments.
In a fifteenth embodiment, the present disclosure provides the reclosabe package of any one of the sixth to fourtheenth embodiments, wherein the post has a base attached to the backing and a distal tip, wherein the distal tip has a cross-sectional area that is less than or equal to a cross-sectional area of the base.
In a sixteenth embodiment, the present disclosure provides the reclosable package of any one of the sixth to fifteenth embodiments, wherein a shortest distance between one of the posts and one of the base portions of the rail segments in adjacent rows is within 20 percent of the cap width.
In a seventeenth embodiment, the present disclosure provides the reclosable package of any one of the sixth to sixteenth embodiments, wherein the fastener has at least three or at least five of the rows of rail segments alternating with at least three or at least five of the rows of posts.
In an eighteenth embodiment, the present disclosure provides the reclosable package of any one of the second to seventeenth embodiments, wherein the at least one of the first fastener member or the second fastener member comprises at least one rib protruding from the backing, the rib having at least a continuous base portion attached to the backing.
In a nineteenth embodiment, the present disclosure provides the reclosable package of the eighteenth embodiment, wherein the rib has a distal portion distal from the backing, wherein the distal portion is provided with a series of notches.
In a twentieth embodiment, the present disclosure provides the reclosable package of the eighteenth or nineteenth embodiment, wherein the rib has a height that is no greater than a height of the rail segments.
In a twenty-first embodiment, the present disclosure provides the reclosable package of the twentieth embodiment, wherein the height of the rib is up to 95 percent of the height of the rail segments.
In a twenty-second embodiment, the present disclosure provides the reclosable package of any one of the first to twenty-first embodiments, wherein at least one of the first fastener member or the second fastener member comprises a backing having a length, a width, and a thickness, with rails protruding from the backing, wherein each of the rails has a continuous base portion attached to the backing and an engaging portion distal from the backing, wherein the engaging portion has a width that is greater than a width of the base portion, wherein the engaging portion overhangs the base portion on opposing sides.
In a twenty-third embodiment, the present disclosure provides the reclosable package of the twenty-second embodiment, wherein the engaging portion overhangs the continuous base portion at amount of at least 25 micrometers on the opposing sides.
In a twenty-fourth embodiment, the present disclosure provides the reclosable package of the twenty-first or twenty-second embodiment, wherein the at least one of the first fastener member or the second fastener member comprises at least one rib protruding from the backing, the rib having at least a continuous base portion attached to the backing.
In a twenty-fifth embodiment, the present disclosure provides the reclosable package of the twenty-fourth embodiment, wherein the rib has a distal portion distal from the backing, wherein the distal portion is provided with a series of notches.
In a twenty-sixth embodiment, the present disclosure provides the reclosable package of the twenty-fourth or twenty-fifth embodiment, wherein the rib has a height that is no greater than a height of the rail segments.
In a twenty-seventh embodiment, the present disclosure provides the reclosable package of the twenty-sixth embodiment, wherein the height of the rib is up to 95 percent of the height of the rail segments.
In a twenty-eighth embodiment, the present disclosure provides the reclosable package of any one of the second to twenty-seventh embodiments, wherein the backing is formed without through-holes.
In a twenty-ninth embodiment, the present disclosure provides the reclosable package of any one of the first to twenty-fourth embodiments, further comprising a tie layer on a second major surface of at least one of the first and second fastener members opposite the first major surface of the first and second fastener members.
In a thirtieth embodiment, the present disclosure provides the reclosable package of the twenty-ninth embodiment, wherein the tie layer comprises a polyolefin elastomer.
In a thirty-first embodiment, the present disclosure provides the reclosable package of any one of the first to thirtieth embodiments, further comprising a pressure sensitive adhesive on a second major surface of at least one of the first and second fastener members opposite the first major surface of the first and second fastener members.
In a thirty-second embodiment, the present disclosure provides the reclosable package of any one of the first to thirty-first embodiments, wherein when the first and second fastener members are fastened, they can slide relative to each other in a direction parallel to upper seal region.
In a thirty-third embodiment, the present disclosure provides the reclosable package of any one of the first to thirty-second embodiments, wherein in the closed configuration, the self-mating fastener has a thickness of at least 200 micrometers.
In a thirty-fourth embodiment, the present disclosure provides the reclosable package of any one of the first to thirty-third embodiments, wherein at least one of the first fastener member or the second fastener member comprises adhesive on at least a portion of its first major surface.
In a thirty-fifth embodiment, the present disclosure provides a process for making the reclosable package of any one of the first to thirty-fourth embodiments, the process comprising:
-
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of self-mated fastening strips in a central portion of the film not including the first or second longitudinal edges, wherein each of the self-mated fastening strips extends perpendicular to the first and second longitudinal edges of the film and comprises:
- the first and second fastener members each having first major surfaces with fastener elements engaged together,
- a length up to fifty percent of the distance between the first and second opposing longitudinal edges, and
- a thickness of up to 800 micrometers, wherein the second major surface of the first fastener member is attached to the film, and the second major surface of the second fastener member is exposed to an interior of the tube of film;
- bringing the first and second longitudinal edges into contact;
- sealing the first and second longitudinal edges together to form a vertical seal; and
- attaching the second major surface of the second fastener member to the film over the vertical seal. In some of these embodiments, bring the first and second longitudinal edges into contact includes overlapping the first and second longitudinal edges, sealing includes sealing the first and second longitudinal edges while they are overlapped.
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of self-mated fastening strips in a central portion of the film not including the first or second longitudinal edges, wherein each of the self-mated fastening strips extends perpendicular to the first and second longitudinal edges of the film and comprises:
In a thirty-sixth embodiment, the present disclosure provides the process of the thirty-fifth embodiment, wherein the first fastener member and the second fastener member are formed from a unitary strip of material, folded over onto itself.
In a thirty-seventh embodiment, the present disclosure provides the process of the thirty-fifth embodiment, wherein the first fastener member and the second fastener member do not share a unitary backing.
In a thirty-eighth embodiment, the present disclosure provides the process of any one of the thirty-fifth to thirty-seventh embodiments, wherein the reclosable package has a width between opposing first and second side edges, wherein the self-mated fastener has a first end portion adjacent the first side edge and a second end portion adjacent the second side edge, the process further comprising:
-
- sealing the first end portion of the self-mated fastener and any opening between the first end portion and the first side edge of the reclosable package; and
- sealing the second end portion of the self-mated fastener and any opening between the second end portion and the second side edge of the reclosable package.
In a thirty-ninth embodiment, the present disclosure provides the process of any one of the thirty-fifth to thirty-eighth embodiments, wherein the second major surface of the first fastener member is attached to the film with a pressure sensitive adhesive.
In a fortieth embodiment, the present disclosure provides the process of any one of the thirty-fifth to thirty-ninth embodiments, wherein the second major surface of the second fastener member is provided with a tie layer to attach the second fastener member to the film.
In a forty-first embodiment, the present disclosure provides the reclosable package of the fortieth embodiment, wherein the tie layer comprises a polyolefin elastomer.
In a forty-second embodiment, the present disclosure provides a process for making the reclosable package of any one of the first to thirty-fourth embodiments, the process comprising:
-
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of fastening strips extending perpendicularly to the first and second longitudinal edges, wherein each of the fastening strips comprises:
- a first major surfaces with fastener elements exposed to an interior of the tube of film,
- a second major surface attached to the film, and
- a thickness of up to 800 micrometers;
- bringing together the first and second longitudinal edges; and
- sealing the first and second longitudinal edges together to form a vertical seal. In some of these embodiments, bring the first and second longitudinal edges into contact includes overlapping the first and second longitudinal edges, sealing includes sealing the first and second longitudinal edges while they are overlapped.
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of fastening strips extending perpendicularly to the first and second longitudinal edges, wherein each of the fastening strips comprises:
In a forty-second embodiment, the present disclosure provides the process of any one of the thirty-fifth to forty-first embodiment, further comprising forming a lower seal perpendicular to the vertical seal to form a bottom edge of the reclosable package.
In a forty-third embodiment, the present disclosure provides the process of any one of the thirty-fifth to forty-second embodiments, further comprising dispensing consumer goods into the reclosable package.
In a forty-fourth embodiment, the present disclosure provides the process of any one of the thirty-fifth to forty-third embodiments, further comprising forming an upper seal in the reclosable package perpendicular to the vertical seal such that one of the self-mated fastening strips is between the upper seal and bottom seal and closer to the upper seal.
In order that this disclosure can be more fully understood, the following examples are set forth. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this disclosure in any manner.
EXAMPLES T-Peel Test MethodThe force to open values for a self-mating fastener can be determined utilizing ASTM D1876 (designation D1876-08(2015)e1). In general, a standard T-Peel test as defined by ASTM D1876 is performed at an extension rate of 12-inches per minute (30.5 cm/minute) on a representative sample in both the machine and cross web directions and can be utilized to determine whether the closure is in the open or closed configuration. For example, as shown in
T-Peel was measured using strips that were 14 inches (35.6 cm) long in the machine direction and having the widths described below. Each strip was folded in half and self-mated to provide a specimen. A calibrated 11.5-pound (5.22 kg) stainless steel roller was used to roll down the specimen. The roller was applied for a full round trip back and forth on each side of the specimen. The ends of the specimen were peeled open so that one inch (2.54 cm) was separated on each end. The separated portions were bent perpendicular to the specimen plane for clamping in the grips of the Instron machine. A cross-head speed of 12-inches per minute (30.5 cm/minute) was used to peel open the specimen over a distance of 4.5 inches (11.4 cm). Three replicates were used per specimen.
Force to Close Test MethodThe force required to close a fastener was measured by pulling an open strip of closure device through a set gap, at a rate of 12 in/minute (30.5 cm/minute). Either side of the gap was composed of a radial piece of PTFE to minimize friction while maintaining said gap. A multi-directional load cell is utilized to measure the force normal and tangential to the closure device. The average kinetic peel force is obtained by averaging the force 1 inch (2.54 cm) after closure begins and 1 inch (2.54 cm) before closure ends. This measurement is repeated for a total of 3 measurements, which are then averaged.
Utilizing the Force to Close Test Method, the tactile response to a fastener can be obtained by calculating the average amplitude between the first 50 peaks and the first 50 troughs of the kinetic peel force curve.
Flexural Stiffness Test MethodASTM D790 (2003) is utilized to measure the flexural rigidity of a specimen. A universal testing machine is used with a 3-point bend fixture. The test specimens were closed, flattened, and placed in the 3-point bend fixture. The gap between the bottom 2 points is set to 12 mm and the force to displace the sample a set distance is measured. The upper compression point diameter was 4 mm, and the support diameters were 5 mm. The upper compression point is advanced at a linear rate of 12 in/minute (30.5 cm/minute). Flexural stiffness is derived from the first primary slope of the force versus displacement curve before the fastening elements slip and begin to slide past one another resulting in a second primary slope
Air Seal MeasurementA 5-inch by 5-inch (12.7-cm by 12.7-cm) bag was made where the 5-inch-long fastener strip was bonded to the packaging film with double sided tape. The width of the fastening strip was 9 mm. The edges of the fastening strip were heat sealed shut to the packaging film to eliminate air escape. Clips were used on the outside of the fastening strip to keep the closure from opening from the compressed air pressure inside the bag and to ensure air flow going through the fastening strip was recorded. Low volume compressed air was introduced into the bottom of the bag which was sealed at the bottom. Higher air pressure means a better air seal for the bag. Three data points were collected for each example and averaged.
For Examples 1 to 4 and 6 to 9, a tool roll was created using rings that were laser cut or EDM wire cut with the desired shape and depth of a mold cavity that the molded article would replicate when it is removed from the mold after cooling and solidifying. A combination of spacer rings having 0.015-inch (0.381-mm) thickness and shaped rings having 0.005-inch (0.127-mm) thickness, each made of Stainless Steel 304, were used. The shaped rings included those formed with cavities and/or those with lower diameters and having protrusions. The vertical sides of the shaped rings and spacer rings had a surface roughness suitable for allowing air to escape when filling the mold with molten polymer, typically 100 ra to 150 ra.
For each of Examples 1 to 4 and 6 to 9, a combination of spacer rings and shaped rings selected to provide the desired array in the molded articles were stacked onto an aluminum mandrel and compressed with end loaded caps. The size and shape of the cavities, depressions, and protrusions made from the combination of rings is reflected in the dimensions of the molded articles, reported in the tables, below. The internal ID of the rings was within +/−0.002 inches (0.05 mm) of the diameter of the mandrel at room temperature. The mandrel was a water pressure vessel that can be heated and cooled with water. To load the rings, the mandrel was cooled at 40° F. (4.44° C.).
Example 1A twin screw 40-mm extruder was used to extrude a food grade MDPE (medium density polyethylene) obtained from Dow Chemical USA, Inc., under the trade designation Dowlex 2027G”. A 1.5-inch (3.8-cm) single screw extruder was used to extrude a combination of 70% by weight of the “VISTAMAXX 3980FL” Performance Polymer and 30% by weight of a low-density polyethylene obtained from The Dow Chemical Company, Midland, Mich., under the trade designation “DOW LDPE 722”. Both feed streams were introduced to a die manifold on the top of a flat sheet die manufactured by Cloeren Inc., Orange, Tex. Molten polymer was extruded nominally at 220° C. from the flat sheet die as a sheet into a rolling cast extrusion takeaway nip with a rubber roll and a tooling roll with the layer including the 100% by weight food grade MDPE against the tooling roll and the layer including 70% by weight “VISTAMAXX 3980FL” Performance Polymer against the rubber roll. The rubber roll forced the molten polymer into the tooling roll having a nominal surface temperature of 50° C. to 75° C. The molten polymer solidified on the roll, and the structured film was removed from the molding roll after a 180-degree wrap from the rubber roll nip point as described by U.S. Pat. No. 6,106,922 (Cejka). The tool roll had a combination of cavities for providing rail segments and cavities for providing posts having different heights, with the cavities providing the rail segments being deeper than the cavities providing the posts.
The rail segments were capped using the method described in U.S. Pat. No. 5,868,987 (Kampfer) to produce caps having peaks and grooves. The web was slit into strips having a width of 13 mm. When tested by hand by folding a strip onto itself, the fastener was easy to close and had sufficient resistance to peel open. Dimensions of the fastener are provided in Table 1, below.
Example 2The web made in Example 1 was further subjected to the method described in U.S. Pat. No. 6,132,660 (Kampfer) to deform the caps and turn a portion of the caps downward toward the backing. Part of the web was slit into strips having a width of 13 mm, and part of the web was slit into strips having a width of 9mm. When a 13-mm strip of the self-mating fastener was folded over onto itself as shown in FIG. 10C, it had a thickness of less than 30 mil (762 micrometers). When tested by hand, the fastener was easy to close and had resistance to peel open sufficient to hold contents in a bag without spilling.
The layer on the smooth side was thermally activated using high-temperature impingement air at 200° C. as described in U.S. Pat. Nos. 9,126,224 (Biegler) and U.S. Pat. No. 8,956,496 (Biegler) and bonded to a 5-layer printed polyolefin packaging film without impacting the quality of the printing and with minimal to no visible film distortion. The high-temperature impingement air was directed to both the layer on the smooth side of the fastener and to one side of the polyolefin packaging film. The bond strength between the fastener and the packaging film was deemed adequate since cohesive failure in the layers of the packaging film was observed when removal of the fastener was carried out by hand.
Fifteen 13-mm strips were sampled from different zones of the web. These specimens were evaluated according to the T-Peel Test Method described above. The T-peel test was carried out in the machine direction (MD) of the specimens. For the 15 13-mm samples, the mean maximum load was 0.424 N, with a standard deviation of 0.055 N, and the mean average load was 0.302 N, with a standard deviation of 0.052 N.
Example 3Example 3 was prepared as described in Example 1 with the modification that 100% food grade medium density polyethylene obtained from The Dow Chemical Company under the trade designation “DOWLEX 2027G MDPE” was substituted with a 90% polypropylene from Total under trade name 3571 and 10% “VISTAMAXX 3980FL” Performance Polymer. A capping roll having a smooth surface was used to produce smooth caps instead of the caps having peaks and grooves. The caps had an appearance such as that shown in
Before being bonded to the packaging film, the web made in Example 3 was further subjected to the method described in U.S. Pat. No. 6,132,660 (Kampfer) to deform the caps and turn a portion of the caps downward toward the backing. The resulting self-mating fastener had an appearance shown in
Six 13-mm strips were sampled from three different zones of the web in the cross-direction, one toward each edge and one toward the center of the web. Two strips were sampled from each zone. Similarly, eighteen 9-mm strips were sampled from the three zones, six from each zone. These specimens were each evaluated using the Force to Close Test Method described above. The maximum and minimum kinetic peel force to close at 12 inches per minute from the set of specimens were 2.37 N and 0.6 N, respectively, with maximum and minimum average kinetic peak oscillation amplitude of 0.84 N and 0.39 N, respectively. When the data were normalized against the two different widths, the maximum and minimum kinetic peel force to close at 12 inches per minute from the set of specimens were 2.1 N and 0.69 N, respectively, with maximum and minimum average kinetic peak oscillation amplitude of 0.93 N and 0.006 N, respectively.
Six 13-mm strips and eighteen 9-mm strips were sampled from the three different zones of the web as described above. These specimens were each evaluated using the Flexural Stiffness Test Method described above. For these specimens, the flexural rigidity ranged from 221.7 mN/mm to 1149.3 mN/mm with an average of 601.0 mN/mm and a standard deviation of 221.7 mN/mm. The reported flexural rigidity was the slope of the first leg of the force vs displacement curve from the 3 point bend before the rail segments begin to slide against one another. None of the specimens was observed to open during the 3 point bend.
Fifteen 13-mm strips were sampled from different zones of the web. These specimens were evaluated according to the T-Peel Test Method described above. The T-peel test was carried out in the machine direction (MD) of the specimens. For the 15 13-mm samples, the mean maximum load was 0.511 N, with a standard deviation of 0.072 N, and the mean average load was 0.339 N, with a standard deviation of 0.056 N.
Sixteen 9-mm strips were sampled from different zones of the web. These specimens were evaluated according to the T-Peel Test Method described above. The T-peel test was carried out in the machine direction (MD) of the specimens. For the 18 9-mm samples, the mean maximum load was 0.562 N, with a standard deviation of 0.062 N, and the mean average load was 0.351 N, with a standard deviation of 0.049 N.
To assess whether fastener member designs can be in the fastened and unfastened configurations one or more times without destroying the functionality of the fastener, a Finite Element Model (FEM) was developed to capture the effects of system deformation on plastic strain generation in the features. A fastener having rail segments and posts like that shown in
A FEM was developed using the definitions of Example 5. Similar fastening features were used in this model in a capped rail to capped rail system construction. The nominal strain state in the final fastened configuration results in 20.15% permanent plastic deformation, which may reduce the fastener's useful lifetime.
Example 6 Fastener as Shown in FIG. 11A twin screw 40-mm extruder was used to extrude a blend of 90% by weight food grade Total 3571 homopolymer polypropylene obtained from Total Petrochemicals, Houston, Tex. and 10% by weight “VISTAMAXX 3980FL” Performance Polymer obtained from ExxonMobil, Irving, Tex. A second 1.5-inch (3.8-cm) single screw extruder used to extrude 100% “VISTAMAXX 3980FL” Performance Polymer. Both polymer streams were introduced to an A/B die manifold situated on top of a Cloeren flat sheet die manufactured by Cloeren Inc, Orange Tex). Molten polymer was extruded nominally at 220° C. into a rolling cast extrusion takeaway nip with a rubber roll and a tooling roll with the layer including the Total 3571/“VISTAMAXX 3980FL” Performance Polymer blend against the tooling roll and the layer including 100% “VISTAMAXX 3980FL” Performance Polymer against the rubber roll. The pressure in the nip was 100 pounds per lineal inch (pli) (571 N/mm). The rubber forced the molten polymer blend into the tooling roll having a nominal surface temperature of 50° C. to 75° C. The molten polymer solidified on the roll and the structured film was removed from the molding roll after an 180-degree wrap from the rubber roll as described by U.S. Pat. No. 6,106,922 (Cejka). The layer of 100% “VISTAMAXX 3980FL” contacted the rubber roll and subsequently had a thickness of 10 micrometers. The tool roll had a combination of cavities providing discontinuous rail segments deeper then shorter continuous rail segments. The cavities providing continuous rail segments have protrusions to improve polymer filling of the continuous rails the low nip pressure. The sample was weighed, and it measured nominally 165 grams per square meter (gsm).
The rail segments were capped using the method described in U.S. Pat. No. 5,868,987 (Kampfer) to produce caps having peaks and grooves. The web was slit into strips having a width of 9 mm. When tested by hand by folding a strip onto itself, the fastener was easy to close and had sufficient resistance to peel open. The thickness in this closed configuration was measured to be 723.9 micrometers. After capping the taller rails, the fastener was bonded to a multi-layer polyolefin packaging film using a heat press at 250° F. (121° C.). The bond strength between the fastener and the packaging film was deemed adequate since cohesive failure in the layers of the packaging film was observed when removal of the fastener was carried out by hand. Dimensions of the fastener are provided in Table 2, below.
Example 7 Fastener as Shown in FIG. 13A tool roll as described above was used to create a structure of tall and short repeating continuous ribs. Protrusions in the rib-forming grooves were used to improve polymer filling of the continuous rails the low nip pressure. Example 7 was made using the same materials and method as Example 6. The sample was weighed, and it measured 190 gsm. The thickness of the fastener when it was folded over onto itself to engage the capped rails was measured to be 731 micrometers. Dimensions of the fastener are provided in Table 2, below.
Example 8 Fastener as Shown in FIG. 10AA tool roll as described above had a combination of cavities for providing rail segments and cavities for providing posts having different heights, with the cavities providing the rail segments being deeper than the cavities providing the posts. Example 8 was made using the same material and method as Example 6. The thickness of the fastener when it was folded over onto itself to engage the rail segments was measured to be 636 micrometers. Dimensions of the fastener are provided in Table 2, below.
Example 9 Fastener as Shown in FIG. 12A tool roll surface was created having cavities to provide discontinuous rail segments, posts, and a section with continuous ribs with notches. Example 9 was carried out using the materials and methods of Example 6. The straight continuous ribs shown in
Examples 6 to 8 were evaluated using the Air Seal Measurement Method described above. The results are shown in Table 3, below.
Various modifications and alterations of this disclosure may be made by those skilled the art without departing from the scope and spirit of the disclosure, and it should be understood that this disclosure is not to be unduly limited to the illustrative embodiments set forth herein. All patents and patent applications cited above are hereby incorporated by reference into this document in their entirety.
Claims
1. A reclosable package comprising:
- a front panel;
- a back panel opposite the front panel;
- an upper seal region at a top end of the resealable package, wherein the upper seal extends between a first side edge and an opposing second side edge, and wherein the upper seal region is adapted to be broken to allow a first opening of the reclosable package;
- a lower seal at a bottom end of the resealable package, opposite the upper seal region, wherein the lower seal region extends between the first side edge and the opposing second side edge;
- a vertical seal perpendicular to and extending between the upper seal region and the lower seal on the back panel, wherein the vertical seal is located between the first side edge and the opposing second side edge; and
- a self-mating fastener disposed adjacent the upper seal region in an interior of the reclosable package, wherein the self-mating fastener comprises:
- first and second fastener members each having first major surfaces with fastener elements,
- an open configuration to allow access to the interior volume of the reclosable package, and
- a closed configuration in which the fastener elements of the first and second fastener members are engaged together, wherein in the closed configuration, the self-mating fastener has a thickness of up to 800 micrometers.
2. The reclosable package of claim 1, wherein at least one of the first fastener member or the second fastener member comprises a backing having a length, a width, and a thickness, with rows of rail segments protruding from the backing, wherein each of the rail segments has a base portion attached to the backing and a cap portion distal from the backing, wherein the cap portion has a cap width that is greater than a width of the base portion, wherein the cap portion overhangs the base portion on opposing sides, wherein the base portion has a length that is greater than the width of the base portion.
3. The reclosable package of claim 2, wherein the at least one of the first fastener member or the second fastener member comprises rows of posts protruding perpendicularly from the backing, wherein the rows of rail segments and rows of posts alternate, and wherein each of the posts has a height that is no greater than a height of the rail segments and a length that is different from the length of the rail segments.
4. The reclosable package of claim 2, wherein the at least one of the first fastener member or the second fastener member comprises at least one rib protruding from the backing between at least one row of rail segments and an adjacent row of posts, the rib having at least a continuous base portion attached to the backing.
5. The reclosable package of claim 1, wherein at least one of the first fastener member or the second fastener member comprises a backing having a length, a width, and a thickness, with rails protruding from the backing, wherein each of the rails has a continuous base portion attached to the backing and an engaging portion distal from the backing, wherein the engaging portion has a width that is greater than a width of the base portion, wherein the engaging portion overhangs the base portion on opposing sides.
6. The reclosable package of claim 1, wherein in the closed configuration, the self-mating fastener has a thickness of at least 200 micrometers.
7. The reclosable package of claim 1, wherein when the first and second fastener members are fastened, they can slide relative to each other in a direction parallel to upper seal region.
8. The reclosable package of claim 1, wherein at least one of the first fastener member or the second fastener member comprises adhesive on at least a portion of its first major surface.
9. A process for making the reclosable package of claim 1, the process comprising:
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of self-mated fastening strips in a central portion of the film not including the first or second longitudinal edges, wherein each of the self-mated fastening strips extends perpendicular to the first and second longitudinal edges of the film and comprises: first and second fastener members each having first major surfaces with fastener elements engaged together, a length up to fifty percent of the distance between the first and second opposing longitudinal edges, and a thickness of up to 800 micrometers, wherein the second major surface of the first fastener member is attached to the film, and the second major surface of the second fastener member is exposed to an interior of the tube of film;
- bringing the first and second longitudinal edges into contact;
- sealing the first and second longitudinal edges together to form a vertical seal; and
- attaching the second major surface of the second fastener member to the film over the vertical seal.
10. The process of claim 9, wherein the first fastener member and the second fastener member are formed from a unitary strip of material, folded over onto itself.
11. The process of claim 9, wherein the first fastener member and the second fastener member do not share a unitary backing.
12. The process of claim 9, wherein the reclosable package has a width between opposing first and second side edges, wherein the self-mated fastener has a first end portion adjacent the first side edge and a second end portion adjacent the second side edge, process further comprising:
- sealing the first end portion of the self-mated fastener and any opening between the first end portion and the first side edge of the reclosable package; and
- sealing the second end portion of the self-mated fastener and any opening between the second end portion and the second side edge of the reclosable package.
13. A process for making the reclosable package of claim 1, the process comprising:
- wrapping a film around a former to provide a tube of film, wherein the film comprises first and second opposing longitudinal edges, a distance between the first and second opposing longitudinal edges, and a row of fastening strips extending perpendicularly to the first and second longitudinal edges, wherein each of the fastening strips comprises: a first major surfaces with fastener elements exposed to an interior of the tube of film, a second major surface attached to the film, a first end portion closer to the first longitudinal edge and a second end portion closer to the second longitudinal edge, and a thickness of up to 800 micrometers;
- bringing together the first and second longitudinal edges; and
- sealing the first and second longitudinal edges together to form a vertical seal.
14. The process of claim 13, further comprising forming a lower seal perpendicular to the vertical seal to form a bottom edge of the reclosable package.
15. The process of claim 13, further comprising forming an upper seal in the reclosable package perpendicular to the vertical seal such that one of the self-mated fastening strips is between the upper seal and bottom seal and closer to the upper seal.
16. The reclosable package of claim 5, wherein the engaging portion overhangs the continuous base portion at amount of at least 25 micrometers on the opposing sides.
17. The reclosable package of claim 5, wherein the at least one of the first fastener member or the second fastener member comprises at least one rib protruding from the backing, the rib having at least a continuous base portion attached to the backing.
18. The reclosable package of claim 17, wherein the rib has a height that is no greater than a height of the rail segments.
19. The reclosable package of claim 1, further comprising a tie layer on a second major surface of at least one of the first and second fastener members opposite the first major surface of the first and second fastener members.
20. The reclosable package of claim 19, wherein the tie layer comprises a polyolefin elastomer.
Type: Application
Filed: May 27, 2020
Publication Date: Feb 8, 2024
Inventors: Michael R. Gorman (Woodbury, MN), Ryan M. Luepke (Eagan, MN), Thomas R. LaLiberte (Inver Grove Heights, MN), Randall L. Alberg (Maplewood, MN), Timothy P. Pariseau (Forest Lake, MN), Dylan T. Cosgrove (Oakdale, MN), Scott M. Niemi (St. Paul, MN), Alex P. Beane (Burnsville, MN), Richard L. Peloquin (Maplewood, MN), Jackson T. Shulman (Minneapolis, MN), Keith A. Triebold (Hudson, WI), Dylan J.V. Shallbetter (Oakdale, MN)
Application Number: 17/615,194