Pouch
A pouch adapted to accommodate a hygienic article is described. The pouch comprises a body including a longitudinal axis, a transverse axis, and an intended opening axis substantially parallel to the longitudinal axis. The pouch including an oriented, multilayer film laminate. The film laminate includes at least one outer layer comprising 35% to 65% alkaline earth carbonate, the outer layer having a thermal conductivity; and a core layer comprising a lower thermal conductivity that is a lower thermal conductivity than the outer layer. The core layer is in contact with at least one layer of said outer layer. The film laminate is made by coextrusion of the outer layer and the core layer, and subsequent orientation. The film laminate further includes a CD tensile strength and a MD tensile strength wherein a MD:CD tensile strength ratio is at least about 6:1.
This invention relates to a pouches comprised of a thermoplastic orientable polymeric film laminate adapted to accommodate absorbent articles.
BACKGROUND OF THE INVENTIONPouches comprising compound film material adapted to contain foodstuff, medicines, hygienic article and the like are known in the art. However, pouches manufactured by such compound films have considerably large tear strength, i.e. tear resistance, so that much labor is required to tear the pouch to take out the inner content such as medicine. For example, it is hard to open the pouch by usual finger force, requiring a scissor or a knife to cut the pouch and take out the inner content.
In order to solve this problem, there has been proposed a pouch in which a slit is formed in one side portion of the outer side resin film of the pouch having a large tear strength to thereby open the pouch using only fingers with a small force. However, a such pouch having the slit formed in the outside resin film, at the time of manufacturing a compound film by laminating the resin film having the slit on the heat adhesive resin film, may cause the slit to be opened when the resin films are laminated, damaging the hermetic seal. Moreover one end edge of the slit may be overlapped with another end edge forming a staged portion, damaging the opening ability of the pouch. Accordingly, a defective pouch with poor hermetic seal properties may be formed. In an adverse case, it becomes difficult to open the pouch.
Furthermore, in general, the resin film has an orientation along which the resin film is easily tom, and accordingly, even if the slit is formed, an opening line 6, as shown in
Accordingly, pouches have been made in oriented films have been made that will tear easily in a straight line such as described in U.S. Pat. No. 5,045,620 issued to Itaba, et al. on Sep. 3, 1991; U.S. Pat. No. 5,613,779 issued to Niwa, et al. on Sep. 3, 1997; U.S. Pat. No. 4,748,070 issued to Beehler, et al. on May 31, 1988; U.S. Pat. No. 4,633,643 issued to Yeung, et al. on Jan. 6, 1987; U.S. Pat. No. 4,677,007 issued to Murray on Jun. 30, 1987; U.S. Pat. No. 4,974,732 issued to Sullivan, et al. on Dec. 4, 1990, and EP publication 0723,856 A2 published by Burgopack Stampa. However, there is still an opportunity to improve the ease of linear opening of pouches.
Some consumer goods must be stored in a specific way to maintain their usefulness. One such consumer goods are hygienic and absorbent articles. Absorbent articles need to be hygienically stored from the time of their manufacture until the article is used. Specifically, a need exists to hygienically store tampons, sanitary napkins, interlabial devices and pantiliners to prevent transferring unsanitary particles or moisture to the vaginal area.
The packaging for the commercially available FRESH ‘N FIT® PADETTE® hygienic product is made from a coated paper sheet that is wrapped around the product and sealed with adhesive on the transverse ends and along the longitudinal edges and then crimped or knurled together. Other examples of packaging for absorbent article are shown in U.S. Pat. No. 4,743,245 entitled “Labial Sanitary Pad” that issued to F. O . Lassen, et al. on May 10, 1988, U.S. Pat. No. 3,062,371 entitled “Intemally Sterile Composite Pouch” that issued to D. Patience on Nov. 6, 1962, U.S. Pat. No. 3,698,549 entitled “Pouches for Small Articles” that issued to J. A. Glassman on Oct. 17, 1972, U.S. Pat. No. 3,135,262 entitled “Tampon” that, issued to W. Kobler, et al. on Jun. 2, 1964, and U.S. Pat. No. 5,180,059 entitled “Pouch of a Sanitary Tampon” that issued to S. Shimatani and K. Shimatani on Jan. 19, 1993.
Although the packages described in the prior art protect the enclosed article, one drawback is that these packages require the consumer to open the package in a tedious way that is not intuitive to the consumer sometimes causing the consumer to drop the absorbent article or cause the consumer's hand to touch the product. This is significant given the lack of hygiene in restrooms, the need to touch the doors of non-hygienic restrooms, and the necessity to touch themselves while inserting the device, which may result in a possible infection. One possible solution was to devise an individual package in combination with a hygienic device comprising a rupturable seal line adjacent to a permanent seal line comprising a pair of opening members situated on opposite sides of the rupturable seal line according to U.S. Pat No. 6, 478,763 issued to Simonsen, et al. on Nov. 12, 2002. While the package works for its intended purpose, the composition of the package is such that the material comprising it has a high thermal conductivity, so that when a package is made much care must be taken with setting the temperature and time parameters when sealing so that the sealing mechanism does not melt holes in the pouch disruptive the hermetic seal. Because of the sensitivity of the polymeric material to heat, the production time is increased.
An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art and to provide a pouches an opening pouch made of a oriented films have been made that will tear easily in a straight line that also has a thermal seal and an improved hermeticism.
SUMMARY OF THE INVENTIONThe present invention relates to a pouch adapted to accommodate a hygienic article. The pouch comprises a body comprising a longitudinal axis, a transverse axis, and an intended opening axis substantially parallel to the longitudinal axis. The pouch comprises an oriented, multilayer film laminate. The film laminate comprises at least one outer layer comprising 35% to 65% alkaline earth carbonate, the outer layer having a thermal conductivity; and a core layer comprising a lower thermal conductivity that is a lower thermal conductivity than the outer layer.
The core layer is in contact with at least one layer of said outer layer. The film laminate is made by coextrusion of the outer layer and the core layer, and subsequent orientation. The film laminate further comprises a CD tensile strength and a MD tensile strength wherein a MD:CD tensile strength ratio is at least about 6:1 and affords superior sealing and tactile feel.
BRIEF DESCRIPTION OF THE DRAWINGS
As used herein, the term “additives” refers to materials added to the film with the intent of improving specific properties of the plastic as is known in the art including by not limited to anti-static agent, flame retardants, thermal stabilizers, UV stabilizers, compatibilizers, antimicrobial agents (e.g., zinc oxide), electrical conductors, and thermal conductors (e.g., aluminum oxide, boron nitride, aluminum nitride, and nickel particles) colorants, dyes, pigments, processing aids, process stabilizers, fluorescents, antioxidants, fillers, wetting agents, plasticizers and the like.
As used herein, the term “anisotropy” refers to a material that exhibits different properties (optical, X-ray, tensile strength, etc.) when measured along axes in all directions.
The term “anti-static agent” is an adjuvant added to film. Some of the antistatic agents, well known in the art, including aliphatic tertiary amines, glycerol monostearates, alkali metal alkane sulfonates, ethoxylated or propoxylated polydiorganosiloxanes, polyethylene glycol esters, polyethylene glycol ethers, fatty acid esters, ethanol amides, mono- and diglycerides, and ethoxylated fatty amines. Organic or inorganic nucleating agents may also be incorporated, such as dibenzylsorbitol or its derivatives, quinacridone and its derivatives, metal salts of benzoic acid such as sodium benzoate, sodium bis(4-tert-butyl-phenyl)phosphate, silica, talc, and bentonite.
The term “basis weight” is measure by a ISO-4593 test methods. It is measured in g/m2.
As used herein, the term “coefficient of friction” is the measure of and is measured film to film and film to steel by the ASTM-D 1894.
The term “cross direction” or “CD” refers to a direction on the filn at right angles to taken by the film web as it moves through the film making machine. This direction is synonymous with the transverse direction of the film.
The “elongation at break” is measured by the ASTM D 882 test method.
As used herein, “EVA” refers to ethylene vinyl acetate.
The term “film”, as used herein refers to a flexible, thin sheet of polymer. As used herein, the term “filler” refers to materials, added to films whose intent is to modify some aspects of the physical nature of the plastic usually as small particles. Organic fillers may include organic dyes and resins, as well as organic fibers such as nylon and polyamide fibers, and inclusions of other, optionally cross linked, polymers such as polyethylene, polyesters, polycarbonates, polystyrenes, polyamides, halogenated polymers, polymethyl methacrylatc, and cycloolefin polymers. The inorganic filler may include pigments, fumed silica and other forms of silicon dioxide, silicates such as aluminum silicate or magnesium silicate, kaolin, talc, sodium aluminum silicate, potassium aluminum silicate, calcium carbonate, magnesium carbonate, diatomaceous earth, gypsum, aluminum sulfate, barium sulfate, calcium phosphate, aluminum oxide, titanium dioxide, magnesium oxide, iron oxides, carbon fibers, carbon black, graphite, glass beads, glass bubbles, mineral fibers, clay particles, metal particles and the like. The diameter or preferred equivalent spherical diameter of the filler may be between about 0.10 μm to about 5 μm. The particle size distribution of the filler may such that more than about 1% of the particles exceed about 20 μm and fewer than about 1% exceeds 10 μm. The filler loading volume of the outer layer in the pre-compounded blend may be from about 0 to 80 volume percent, or 40 to about 65 volume percent, and may be about 50 volume percent. The filler should have a minimum degree of interaction with the polymer and should not be chemically reactive with respect to the matrix polymer. Further, the melting point of the filler should be sufficiently well above that of the matrix polymer, so that the filler remains substantially undistorted during the pre-compounding and during the melt-extrusion process.
The term “HDPE” is high density polyethylene having a low degree of branching.
As used herein the term “is” is the common dictionary definition and the one used in common parlance.
The term, “isotropic” refers to a material that exhibits the same properties (optical, X-ray, tensile strength, etc.) when measured along axes in all directions.
The term “joined” or “attached,” as used herein, encompasses configurations in which a first element is directly secured to a second element by affixing the first element directly to the second element; configurations in which the first element is indirectly secured to the second element by affixing the first element to intermediate member(s) which in turn are affixed to the second element; and configurations in which the first element is integral with the second element; i.e., the first element is essentially part of the second element.
As used herein, the term “laminate” refers a film comprising layers of firmly united material.
The term, “low-density polyethylene” or “LDPE” refers to the branched polymer produced by the free-radical-initiated polymerization of ethylene at high pressure having a density from about 0.9112 to about 0.935 g/cc.
The term, “linear-low density polyethylene” or “LLDPE” refers to the largely linear polymer produced by the polymerization of ethylene at relatively low pressure with other alkenes, such as 1- butene and 1-alkenes.
The term “machine direction” or “MD” as used herein refers to a direction on the film as it moves through the film making machine. This direction is synonymous with the longitudinal axis of the film.
As used herein, the term “MDPE” is medium density polyethylene and term “MLLDPE” is metallocene linear low-density polyethylene.
The term “Moisture Vapour Transmission Rate” or “MVTR” is the measure of a films breathability as is measured according to the ASTM F-1249 test method at 23° C./85% RH.
As used herein, “orientable” refers to polymers whose chains may be oriented usually by a process that strains the film.
The term, “PE” is polyethylene, the term “PET” is polyethylene terephthalate and the term, “PP” as used herein is polypropylene.
As used herein, the term “polymer” generally includes, but is not limited to, homopolymers, copolymers, (such as for example, block, graft, cross-linked and alternating copolymers, terpolymers, etc.) and blends and modifications thereof. In addition, unless otherwise specifically limited, the term “polymer” includes all possible geometric configurations of the material. The configurations include, but are not limited to, isotactic, atactic, and syndiotactic configurations.
The term, “polymer resin,” as used herein refers to the pre-fill form of compounded polymeric starting material, usually in the form of pellets.
The term, “polyolefin,” as used herein, refers to the collective name given to those thermoplastic polymers that are made from the lower olefms, unsaturated simple hydrocarbon with one double bond per molecule, such as ethylene, propylene, butylenes, hexylene, and octylene.
As used herein, “seal strength” is measured by the ASTM test method F88.
The term “secant modulus” as used herein refers to the ratio of stress in the initial part of the curve, to strain, as of strength to elongation, which is a measure of film stiffiess. The modulus is determined under the ASTM D 882 method.
The term “semi-crystaltine” refers to a polymer that has both amorphous areas and crystalline areas within the polymer structure.
As used herein, the term, “substantially paraller” refers to the orientation of a first line to second line or lines. Substantially parallel means that the first line may be at an angle from a second line, which is from about 85° to about 95°.
The term “tear balance,” is refers to the ratio of tear strength in the transverse direction to the tear strength in the machine direction.
The term “tear strength” is a measure of the film's resistance to tearing propagation of a precut slit. The tear strength is determined under ASTM D- 1992-89.
The term “tensile strength”, as used herein refers to the maximum stress a material subjected to a stretching load can withstand without tearing. The tensile strength at break in the MD direction is measured by the ISO-527 test method. The tensile strength at break in the CD direction is measured by the ASTM D 882 test method.
As used herein, the term “MD:CD tensile strength ratio” refers to ration of the tensile strength in the transverse direction to the tensile strength in the machine direction.
The term “thermoplastic”, as used herein refers to a two-dimensional polymer that can permanently deform by flow under heat and pressure.
As used herein, the term “thickness” is measured by the ASTM-D374 test method.
The term “ULDPE” as used herein ultra low-density polyethylene.
As used herein, the term “VLDPE” is very low-density polyethylene, the term “VLLDP” is very linear low-density polyethylene.
The term “absorbent articles” refers to tampons, sanitary napkins, sanitary panties, interlabial devices, pantiliners, infant diapers, adult incontinence diapers, bandages, surgical swabs, and like that are used for the absorption of fluid therefrom, to aid in wound healing, or for the delivery of active materials, such as medicaments, or moisture.
The term “hygienic articles” as used herein includes absorbent articles, wet wipes and the like used for maintenance of a bodily hygiene.
The term “interlabial pad,” refers to an absorbent article worn in the interlabial space for the absorption of fluid and/or gas therefrom, to aid in wound healing, or for the delivery of active materials, such as medicaments, or moisture. The interlabial pad comprises a liquid pervious topsheet, liquid impervious backsheet and an absorbent core disposed between the topsheet and the backsheet. Examples of such devices are described in U.S. Pat. No. 2,917,049 issued to Delaney on Dec. 15, 1959, U.S. Pat. No. 3,420,235 issued to Harmon on Jan. 7, 1969, U.S. Pat. No. 4,595,392 issued to Johnson, et al. on Jun. 17, 1986, and U.S. Pat. No. 5,484,429 issued to Vukos, et al. on Jan. 16, 1996. A commercially available interlabial device is the INSYNC Miniform interlabial pad which is marketed by A-Fem of Portland, OR and described in U.S. Pat. Nos. 3,983,873 and 4,175,561 issued to Hirschman on Oct. 5, 1976 and Nov. 27, 1979, respectively.
As used herein, the terms “pantiliner,” and “sanitary napkin,” refers to absorbent articles worn external about the pudenal region for the absorption of fluid therefrom, to aid in wound healing, or for the delivery of active materials, such as medicaments, or moisture. Sanitary napkins typically comprise a liquid pervious topsheet, liquid impervious backsheet and an absorbent core disposed between the topsheet and the backsheet. The sanitary napkin, as well as each layer or component thereof can be described as having a “body facing” surface and a “garment facing” surface. Pantiliners and sanitary napkin may have side extensions commonly referred to as “wings,” designed to wrap the sides of the crotch region of the panties of the user of sanitary napkin that may be extension of the topsheet and/or the backsheet. Such devices are disclosed in U.S. Pat. No. 4,463,045 issued to Ahr et al., U.S. Pat. No. 4,556,146 issued to Swanson et al., U.S. Pat. No. 4,950,264 issued to Osborn III, et al. and U.S. Pat. No. 4,687,478 issued to Van Tillburg.
As used herein the term “tampon,” refers to any type of absorbent structure that is inserted into the vaginal canal or other body cavities for the absorption of fluid therefrom, to aid in wound healing, or for the delivery of active materials, such as medicaments, or moisture. Tampon pledget may be constructed from a wide variety of liquid-absorbing materials commonly used in absorbent articles. Tampons invention may optionally comprise an overwrap, secondary absorbent or skirt comprising material such as, rayon, cotton, bicomponent fibers, polyethylene, polypropylene, other suitable natural or synthetic fibers known in the art, and mixtures thereof. Tampons are typically compressed and/or shaped such that it assumes a general shape and size, which is vaginally insertable, absent external forces. Tampons may be digital tampon refers to a tampon which is intended to be inserted into the vaginal canal with the user's finger and without the aid of an applicator and are typically visible to the consumer prior to use rather than being housed in an applicator. Alternatively, the insertion may be aided through the use of any applicator adapted from the prior art including a typical “tube and plunger” type arrangement made of plastic, paper, or other suitable material. Such absorbent articles are disclosed in U.S. Pat. No. 5,087,239 issued to Beastall et al., U.S. Pat. No. 5,279,541 issued to Frayman et al.; U.S. Pat. Nos. 6,258,075 and 6,599,279 both issued to Taylor, et al., U.S. patent application Ser. No. 10/150050, filed Mar. 18, 2002, entitled “Substantially Serpentine Shaped Tampon,” to Randall, et al. and currently pending and commonly assigned, U.S. patent application Ser. No. 10/150055, filed Mar. 18, 2002, entitled “Shaped Tampon,” to Kollowitz, et al.
The term “vaginal cavity,” “within the vagina,” and “vaginal interior,” as used herein, are intended to be synonymous and refer to the internal genitalia of the mammalian female in the pudendal region of the body. The term “vaginal cavity” as used herein is intended to refer to the space located between the introitus of the vagina (sometimes referred to as the sphincter of the vagina or hymeneal ring,) and the cervix. The terms “vaginal cavity,” “within the vagina” and “vaginal interior,” do not include the interlabial space, the floor of vestibule or the externally visible genitalia.
The pouch 10, as shown in
The present invention, as shown in
A suitable method for commercial production of the wrapper is to roll feed in flow wrap-type system. First, the material comprising the pouch 10 is folded the wrapper on its longitudinal axis L. Next, the material comprising the pouch 10 is die cut the hemispherical indention 15 on the first transverse side 14 and hemispherical extension 16 on the second transverse side 17. Then, the pouch 10 is sealed on the first transverse side 14 and the longitudinal side 13. Next, the hygienic article is inserted through the second transverse side 17 substantial parallel to the longitudinal side 13; seal the second transverse side 17. In embodiments of the pouch for dispensing a digital tampon the seal of the first transverse side 14 and the second transverse side 17 are from about 2 mm to about 4 mm wide and the seal of the longitudinal side 13 is from about 10 mm to 13 mm wide. The configuration of the pouch 10 is such that when the hemispherical indention 15 of a first pouch is die cut the hemispherical extension 16 on a second pouch 10 is cut and nested within the hemispherical indention 15 of the first pouch. This configuration of the pouch 10 reduces the amount of scrap material in the cutting process. Thus, the amount of material wasted in cutting this configuration may be negligible, including between from about 0% to about 5% of the material used to produce the pouch 10.
This invention relates to pouches 10 comprised of a thermoplastic polymer film adapted to accommodate hygienic articles. The pouch 10 of the present invention is comprised of a thermoplastic oriented polymeric film. The thermoplastic film exhibits an anisotropy along the MD. The pouch 10 comprises a body comprising having a longitudinal axis, a transverse axis, and an intended opening axis substantially parallel to the longitudinal axis. The pouch 10 comprised of an oriented, thermoplastic, polymeric film. The film comprises a CD tensile strength and a MD tensile strength wherein a MD: CD tensile strength ratio is at least about 6:1. The film may have a MD:CD tensile strength ratio of at least about 7:1. The film may have a MD:CD tensile strength ratio of at least about 8:1. The film may have a MD:CD tensile strength ratio of at least about 9:1.
The pouches 10 of the present invention are formed from oriented, thermoplastic, polymeric film. A variety of polymeric materials are suitable for the pouches of this invention. Thermoplastic orientable polymers include polyolefms, polyvinyl chlorides, polystyrenes, polyamides, polyesters and the like. The thermoplastic orientable polymer may comprise any polyolefm known in the art. The selection of polymers may be based primarily on their molecular orientation predisposition. Thus, polymers with linear orientation may be used such as linear polyolefms including VLLDPE, LLDPE, MLLDPE and mixtures thereof. The polyolefms may have desired low barrier and low temperature thermo-mechanical sealing properties.
The pouch of the present invention may be a single layer structure or a continuous multi-layer co-extruded laminate.
The outer layer 4 may include any alkaline earth carbonate including but not limited to barium carbonate, strontium carbonate, calcium carbonate, magnesium carbonate and the like. One filler that may be used is calcium carbonate, herein after CaCO3. Not to be bound by theory, is it believed that the CaCO3 particles in the polymer mix reduces the melt viscosity and the increases the melt homogeneity due the CaCO3 good thermal conductivity. The outer layer 4 of pouch rapidly melts and may be both sealable and printable.
The core layer 7 may comprise a linear polyolefm copolymer, such as a polypropylene copolymer. The core layer 7 may be made of a different polymeric material composition with better barrier properties and significantly lower thermal conductivity than the compositions than that of the outer layers. The inner layer 8 directly under the outer layer 4 may comprise a plurality of LDPE. The inner layer 8 may comprises a copolymer of 10% ethylene and 90% propylene.
A specific non-limiting example has an outer layer 4 that is 8μm thick, a core layer 7 that is 16μm thick and an inner layer 8 that is 8μm thick. In this non-limiting example, the outer layer 4 is comprised of about 40% to about 70% VLLDPE or LLDPE, from about 30% to about 60% of CaCO3, from about 0% to about 2.5% of an anti-static agent, and from about 0% to about 1.5% of a processing aid. In this non-limiting example, the core layer 7 is comprised of from about 60% to about 90% PP copolymer, from about 0% to about 40% PP—CaCO3 pre-mixed Filler, and from about 10% to about 20% LLDPE. In this non-limiting examples, the inner layer 8 is comprised of from about 40% to about 70% LLDPE, from about 30% to about 60% CaCO3, from about 0% to about 2.5% of an anti-static agent, and from about 0% to about 1.5% of a processing aid.
Non-limiting example 1 has an outer layer 4 that is 8μm thick, a core layer 7 that is 16 μm thick and an inner layer 8 that is 8 μm thick. In this non-limiting example, the outer layer 4 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2 anti-static agent. In this non-limiting example, the core layer 7 is comprised of from about 85 PP copolymer, from about and from about 15% LLDPE. In this non-limiting examples, the inner layer 8 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2 anti-static agent.
Non-limiting example 2 has an outer layer 4 that is 8μm thick, a core layer 7 that is 16 μm thick and an inner layer 8 that is 8 μm thick. In this non-limiting example, the outer layer 4 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2% anti-static agent. In this non-limiting example, the core layer 7 is comprised of from about 80% PP copolymer, from about 10% PP—CaCO3 from about and from about 10% LLDPE. In this non-limiting examples, the inner layer 8 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2 anti-static agent.
Non limiting example 3 has an outer layer 4 that is 8 μm thick, core layer 7 that is 16 μm thick and an inner layer 8 that is 8 μm thick. In this non-limiting example, the outer layer 4 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2 anti-static agent. In this non-limiting example, the core layer 7 is comprised of from about 90% PP copolymer, from about 5% PP—CaCO3 from about and from about 5% LLDPE. In this non-limiting examples, the inner layer 8 is comprised of from about 50% LLDPE, from about 48% of CaCO3, from about 2 anti-static agent.
In one approach, the pouch 10 of the present invention were made by a machine direction orientation process which includes first melt blending a mixture of a polymer, filler, and additives, then flat extrusion casting a precursor, then annealing the precursor and finally subjecting the heat set precursor to sequential uniaxial heated and cooled stretching.
In making the film of the present invention, the polymer, filler and additives may be pre-compounded into blend. The mix of polymers, filler, and additives can be mixed by various methods in the art including but not limited to dry mixing, melt mixing polymers, staged reactor process such as those described in U.S. Pat. No. 5,047,468 and U.S. Pat. No. 5,126,398, other similar processes known in the art.
During the flat extrusion casting, the homogeneity of the skin and core layer can be controlled through rapid cooling process during extrusion in conjunction with optimizing the indented proportions, configuration and thickness. As to extrusion or co-extrusion methods and apparatus for making multiple layer sheet materials, reference is made to commonly owned U.S. Pat. No. 6,228,462 issued to Lee, et al. on May 8, 2001. For further background on pouches and apparatus for producing them, reference is made to U.S. Pat. No. 3,477,099 issued to Lee, et al on Aug. 19, 1965, U.S. Pat. No. 4,755,402 issued to Oberle on Jul. 5, 1988, U.S. Pat. No. 3,558,330 issued to Widiger, et al. on Jan. 26, 1971, U.S. Pat. No. 4,714,638 issued to Lustig, et al. on Dec. 22, 1987, U.S. Pat. No. 4,842,791 issued to Gould, et al on Jun. 27, 1989, U.S. Pat. No. 4,379,117issued to Baird, Jr. on Apr. 5, 1983, and U.S. Pat. No. 4,804,510 issued to Luecke, et al. on Feb. 14, 1989. While the preceded processing technology is flat extrusion casting in particular, it should be understood that this invention is applicable to any process for transforming thin flexible packaging sections which can be formed into a pouches, including tubular extrusion blowing, laminations, extrusions, coextrusion, blown extrusion, tubular water quench extrusion, extrusion coating, and the like, and combinations thereof. Likewise, any process and apparatus may make the pouch of the present invention including, a horizontal pouch forming machine and a vertical form, fill and seal machine.
After the extrusion process, the film precuso is annealed or heat set. The annealing or heat-sealing process is one that is commonly known in the art. After the extrusion process, the film precursor is annealed or heat set. The annealing or heat-sealing process is one that is commonly known in the art such as described in U.S. Pat. No. 6,228,462 issued to Lee, et al. on May 8, 2001; U.S. Pat. No. 5,045,620 issued to Itaba, et al. on Sept. 3, 1991; U.S. Pat. No. 5,613,779 issued to Niwa, et al. on Sep. 3, 1997; U.S. Pat. No. 4,748,070 issued to Beehler, et al. on May 31, 1988; U.S. Pat. No. 4,633,643 issued to Yeung, et al. on Jan. 6, 1987; U.S. Pat. No. 4,677,007 issued to Murray on Jun. 30, 1987; U.S. Pat. No. 4,974,732 issued to Sullivan, et al. on Dec. 4, 1990; and EP publication 0723,856 A2 published by Burgopack Stampa. The machine direction oriented equipment used to anneal and stretch the film can be obtained at Black Clawson Converting Machinery, Inc., Fulton, N.Y. 13069; Reifenhauser GmbH & Co. Mahinenfabrik, Troisdorf, Germany and SML Maschinengesellschaft mbH, Lenzing, Austria.
Furthermore, in addition to the above-disclosed preferred extrusion, annealing, stretching approach, other pouches 10, of either single or multi-layers, comprising polymeric barrier materials can be formed into an easy, controlled tear pouches 10 in accordance with this invention. Suitable materials for such other pouches 10 can be almost any materials conventionally used in the art, e.g., metal foil, PE, MDPE, HDPE, LDPE, LLDPE, VLDPE, PP, ULi)PE, PPE, nylon, EB copolymers, PET, copolymers of PET, or EVA (, or the like, or mixtures thereof. In multiplayer pouches, a tie or an adhesive may also be present between the layers.
Conventional processes, such as blown tubular orientation, stretch orientation, or molecular orientation may also be used to orient the pouch 10 of the present invention. They may also be cross-linked by conventional processes such as by irradiation, heat, or the addition of cross-linking agents.
All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
Claims
1. A pouch adapted to accommodate a hygienic article comprising:
- a body comprising having a longitudinal axis, a transverse axis, and an intended opening axis substantially parallel to the longitudinal axis;
- said pouch comprised of an oriented, multilayer film laminate;
- said film laminate comprising at least one outer layer comprising 35% to 65% alkaline earth carbonate; said outer layer having a thermal conductivity; and
- a core layer comprising a lower thermal conductivity that is lower than said outer layer;
- said core layer being in contact with at least one layer of said outer layer;
- said film laminate being made by coextrusion of said outer layer and said core layer, and subsequent orientation; wherein
- said film laminate further comprises a CD tensile strength and a MD tensile strength wherein a MD:CD tensile strength ratio is at least about 6:1.
2. The pouch according to claim 1 wherein said alkaline earth carbonate is CaCO3.
3. The pouch according to claim 2 wherein said outer layer comprises from about 40% to about 60% of CaCO3.
4. The pouch according to claim 1 wherein the multiplayer laminate comprises at least one outer layer comprising polyethylene and CaCO3 and at least one core layer comprising polypropylene.
5. The pouch according to claim 1 wherein said core layer comprises a copolymer of polypropylene and polyethylene.
6. The pouch of claim 1 wherein said core layer comprises a copolymer of 90% polypropylene and 10% polyethylene.
7. The pouch according to claim 1 wherein the outer layer comprises LDPE.
8. The pouch according to claim 1 wherein the outer layer comprises LLDPE.
9. The pouch of claim 1 wherein the seal strength is greater than the tensile strength.
Type: Application
Filed: Nov 4, 2003
Publication Date: May 5, 2005
Inventor: Samuel Nyambi (Cincinnati, OH)
Application Number: 10/700,987
