Self-engaging, double-sided fastener products
A fastener product includes a base of plastic resin and a plurality of discrete fastener elements having stems of the plastic resin that are integrally molded with and extend from the base. The stems are arranged, as molded, in columns and rows with stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads, with heads of the fastener elements forming the first field constructed to engage the heads of the fastener elements forming the second field to allow releasable fastening.
This invention relates to fastener products, and more particularly to flexible fastener products that can be wrapped about an object with one side of the product overlapping and releasably engaging an opposite side of the product.
BACKGROUNDSelf-engaging fastener products, such as certain wraps and ties, are useful, for example, to close bags or to bundle objects. An example of a product capable of engaging itself is described by Kennedy et al., U.S. Pat. No. 5,260,015, which disclose providing loops on the back side of male fastener tape as the fastener tape substrate and elements are being formed, thus creating a composite fastener tape capable of fastening to itself.
SUMMARYIn aspects, the invention features a fastener product including self-engaging fastener elements having molded stems that extend integrally from opposite sides of a base.
In one aspect, the invention features a base of plastic resin and a plurality of discrete fastener elements having stems of the plastic resin. The stems are integrally molded with and extend from the base and are arranged, as molded, in columns and rows. The stems of some of the fastener elements extend from a first surface of the base forming a first field of fastener elements and stems of the other of the fastener elements project from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
In another aspect, the invention features a fastener product including a base formed of a degradable plastic resin and a plurality of discrete fastener elements having stems formed of the degradable plastic resin that extend from the base. The stems of some of the fastener elements project from a first surface of the base forming a first field of fastener elements and stems of the other of the fastener elements project from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads formed of the degradable plastic resin, with the heads of the fastener elements forming the first field configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
In another aspect, the invention features a method of making a self-engaging fastener product. The method includes molding a flexible, plastic base having multiple, discrete fastener element stems of the plastic resin extending integrally from and molded with the base and arranged in columns and rows. The stems of some of the fastener elements projecting from a first surface of the base forming a first field of stems and stems of the other of the fastener elements projecting from an opposite, second surface of the base forming a second field of stems. Engageable heads are formed that extend outwardly from the stems forming fastener elements extending from the first and second surfaces. The heads of the stems in the first and second fields are configured to engage each other to allow releasable fastening.
Embodiments may include one or more of the following features. The base is of unitary structure of the plastic resin forming the first and second surfaces. In other embodiments, the base includes more than one layer. The layers can be adhered together by an adhesive layer.
In certain embodiments, the plastic resin is degradable, such as a biodegradable and/or compostable resin. The degradable resin may comply with ASTM D6400-99. Suitable degradable plastic resins include naturally derived polymers, polyactic acid and polyvinyl alcohol. In some cases, the degradable resin is formed of a standard commodity resin, such as polyethylene or polypropylene, with a degradable plastic additive included in the plastic matrix. In some embodiments, the fastener product is formed only of degradable plastic resin. The degradable resin can be selected such that it dissolves naturally within the human body. In some embodiments, the fastener product is a plant tie formed or, for example, a photo-degradable plastic resin.
In some embodiments, at least one of the first and second fields includes one or more discrete regions of fastener elements. In some cases, the fastener elements extend over a length of the fastener product. The fastener elements can have heads that overhang the base in one or more discrete directions, or the fastener elements can have heads that overhang the base in multiple directions. In some embodiments, the fastener elements projecting from at least one of the first and second broad surfaces are arranged in a band with a region adjacent the band free of the fastener elements. The fastener elements projecting from each of the first and second surfaces can be arranged in multiple, spaced-apart bands.
Methods can include continuously introducing molten resin to a gap defined adjacent a periphery of a rotating mold roll having an array of cavities for forming stems of fastener elements. The cavities extend inwardly from the mold roll periphery such that the resin at least partially fills the cavities to form stems extending from the first surface of the flexible base while excess resin forms at least part of the flexible base of the product. The resin is solidified and the solidified resin is stripped from the peripheral surface of the mold roll. In some cases, the method includes introducing molten resin to a gap defined between peripheral surfaces of a pair of rotating mold rolls each having an array of cavities for forming the stems. The cavities extend integrally from respective mold roll peripheries such that the resin at least partially fills the cavities to form stems extending from first and second surfaces of the base.
In some embodiments, the step of forming engageable heads includes deforming distal ends of stems extending from the first and second surfaces to form the fastener elements. In some cases, deforming distal ends of the stems includes deforming distal ends of stems extending from one of the first and second surfaces, then deforming distal ends of stems extending from the other of the first and second surfaces. In certain embodiments, deforming distal ends of the stems includes deforming distal ends of the stems extending from one of the first and second surfaces at a first deformation location, then deforming distal ends of the stems extending from the other of the first and second surfaces at a second deformation location that is spaced from the first deformation location. In some embodiments, deforming distal ends of the stems includes simultaneously deforming distal ends of stems of each of the first and second surfaces at a single deformation location. The distal ends of the stems can be deformed within a gap formed between a pair of opposing deformation rolls.
In some embodiments, molding the base with fastener element stems includes molding a first fastener preform and a second fastener preform, each of the fastener preforms including a base layer and an array of fastener element stems extending integrally therefrom. The method can include permanently affixing, e.g., with adhesive and/or within a nip, respective faces of the first and second fastener preforms in an opposing relationship to form the flexible base.
By forming a fastener product capable of self-engagement solely of moldable resin, e.g., in a continuous process, the fastener product can be formed inexpensively and efficiently. Because the fastener product can be formed of a single material, it can be formed entirely from materials, such as biodegradable materials or recyclable materials. These materials can be useful for applications where the user wants the fastener product to dissolve over time, for example, to bundle or tie produce or in medical applications. The fastener product is capable of self-engagement, e.g., without use of typically more expensive loop materials. By forming a base of unitary, solid construction, the need for an added process step of, e.g., adhesive lamination, can be eliminated. Also, a unitary, solid base can provide improved flexibility, e.g., because no adhesives and/or dissimilar materials are required. Molding the product to form discrete, point-like fastener elements tends to provide freedom in choosing a suitable cutting or trimming process to form the self-engaging fastener product.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION Referring to
Each point-like fastener element 12 includes a stem 24 integrally molded with and extending generally perpendicularly from the base 14 to a distal head 26 that overhangs the base 14 on substantially all sides of the stem 24. Referring to
In a high profile example, square stem 24 width WS is about 0.018 inch (0.46 millimeter), and major head dimension Wh is about 0.0378 inch (0.960 millimeters). In this high profile example, the overall thickness tf of the fastener is about 0.040 to 0.115 inch (1.0 to 2.9 millimeters), with a base thickness of 0.008 to 0.020 inch (0.2 to 0.5 millimeter).
Other configurations are also possible. For example, some stems are inserted through the fastener base as separate elements, rather than being integrally molded of the same material. Such assembly processes can be more expensive, however, than integral molding. The stems may also be of different cross-section than square or rectangular. For example, some stems of circular cross-section can be molded integrally with the base on a roll having plates with aligned, half-cylinder grooves machined or etched into their side surfaces, with the grooves of each abutting plate aligned with those of the next to form cylindrical stem molding cavities. Fastener elements having crook-shaped heads are also contemplated. These heads can extend over the base in one or more discrete directions.
Referring next to
The grouping of fastener element rows into three row groupings, each with a middle staggered row B and spaced from adjacent groups, can be particularly advantageous for self-engagement performance as it provides a sufficient bulk locking ratio at a particularly low head density. Each row group defines a longitudinal row of inter-element receptacles 30, each bounded by four fastener elements 12 and sized to receive and hold a fastener element head of a mating array on at least three sides. One such receptacle 30 is illustrated between four highlighted fastener elements, with the dashed outline of a fastener element head 26′ engaging between the highlighted fastener elements. Given the above inter-row spacing, inter-element spacing and head diameters, the clearance C1 between adjacent heads along each row is about 0.02 inch (0.5 millimeter), or slightly less than the nominal head diameter, while the clearance C2 between transversely aligned fastener elements is about 0.03 inch (0.75 millimeter), or slightly greater than the nominal head diameter. Thus, a mating fastener element head 26′ need only laterally deflect one fastener element of middle row B during engagement.
Fastener elements having the above dimensions and arranged in the pattern of
In a high profile example of the pattern of
Other patterns are contemplated. For example, the patterns described above may be scaled up or down (e.g., scaled down by one-half). Examples of suitable patterns are described in U.S. Pat. No. 6,687,962, the entire contents of which are incorporated herein by reference.
The field of fastener elements 12 can extend along the entire length L of the fastener product 10, as shown by
Referring now to
The fastener preforms 52a and 52b can be directed to the nip 64 as part of the continued molding and forming process described above with reference to
Fastener products can be formed by, e.g., die cutting, rotary cutting and/or perforating sheet 55 along predetermined boundaries. Preferably, the preform sheet 55 is cut and/or perforated such that multiple, interconnected straps can be packaged on a continuous roll and, for example, later separated by hand and/or by machine. In some cases, the sheet 55 is cut (e.g., by rotary cutting) into individual fastener products and, for example, packaged loose in a box or a bag. For example, referring to
As noted above, the fastener product can be formed of a single material, such as polyethylene or polypropylene. Typically, loop materials are the more expensive component of a hook and loop fastener, thus self-engaging, double-sided fastener products formed completely of, for example, an inexpensive polyethylene or polypropylene may be relatively inexpensive compared to straps requiring loop materials. The above-described fastener products can be used, for example, to bundle cord, hoses, wires or any other application for which a bundle tie or strap may be useful.
Referring now to
Self-engaging, degradable fastener products can also be formed, e.g., using the process described above with reference to
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, other fastener product configurations are contemplated such as those described by U.S. Provisional Application 60/547,212, filed Feb. 24, 2004 titled “Fastener Products”, the contents of which are hereby incorporated by reference as if fully set forth herein. Accordingly, other embodiments are within the scope of the following claims.
Claims
1. A fastener product comprising:
- a base of plastic resin; and
- a plurality of discrete fastener elements having stems of the plastic resin that are integrally molded with and extend from the base arranged, as molded, in columns and rows, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements;
- the fastener elements including engageable heads wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
2. The fastener product of claim 1, wherein the base comprises a unitary structure of the plastic resin, the unitary structure defining the first and second surfaces.
3. The fastener product of claim 1, wherein the base comprises more than one layer.
4. The fastener product of claim 3, wherein the layers are adhered together by an adhesive layer.
5. The fastener product of claim 1, wherein at least one of the first and second fields of fastener elements comprises one or more discrete regions of fastener elements.
6. The fastener product of claim 1, wherein the fastener elements of at least one of the first and second fields extend over a length of the fastener product.
7. The fastener product of claim 1, wherein the fastener elements have heads that overhang the base in one or more discrete directions.
8. The fastener product of claim 1, wherein the fastener elements have heads that overhang the base in multiple directions.
9. The fastener product of claim 1, wherein fastener elements projecting from at least one of the first and second surfaces are arranged in a band with a region adjacent the band free of the fastener elements.
10. The fastener product of claim 9, wherein the fastener elements projecting from each of the first and second surfaces are arranged in multiple, spaced-apart bands.
11. The fastener product of claim 1, wherein the plastic resin is a biodegradable or compostable material.
12. The fastener product of claim 11, wherein the plastic resin complies with ASTM D6400-99.
13. The fastener product of claim 1, wherein the plastic resin is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
14. The fastener product of claim 1, wherein the plastic resin comprises a degradable plastic additive.
15. A fastener product comprising:
- a base comprising degradable plastic resin; and
- a plurality of discrete fastener elements having stems of the degradable plastic resin that extend from the base, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements;
- the fastener elements including engageable heads formed of the degradable plastic resin wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
16. The fastener product of claim 15, wherein the degradable plastic resin complies with ASTM D6400-99.
17. The fastener product of claim 15, wherein the degradable plastic resin is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
18. The fastener product of claim 15, wherein the degradable plastic resin comprises a standard commodity resin and a degradable plastic additive.
19. The fastener product of claim 15, wherein the base comprises a unitary structure of the plastic resin, the unitary structure defining the first and second surfaces.
20. The fastener product of claim 15, wherein the base comprises more than one layer.
21. The fastener product of claim 20, wherein the layers are adhered together by an adhesive layer.
22. The fastener product of claim 15 consisting of the degradable plastic resin.
23. The fastener product of claim 22, wherein the degradable plastic resin dissolves naturally in a human body.
24. The fastener product of claim 23, wherein the degradable plastic resin comprises polyactic acid.
25. The fastener product of claim 22 in the form of a plant tie.
26. The fastener product of claim 25, wherein the degradable material is photo-degradable.
27. A method of making a self-engaging fastener product, the method comprising:
- molding a flexible, plastic base of plastic resin having multiple, discrete fastener element stems of the plastic resin extending integrally from and molded with the base and arranged in columns and rows, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of stems and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of stems; and
- forming engageable heads extending outwardly from the stems forming fastener elements extending from the first and second surfaces, the heads of stems in the first and second fields being configured to engage each other to allow releasable fastening.
28. The method of claim 27, wherein the step of molding comprises
- continuously introducing molten resin to a gap defined adjacent a periphery of a rotating mold roll having an array of cavities for forming stems of fastener elements, the cavities extending inwardly from the mold roll periphery, such that the resin at least partially fills the cavities to form stems extending integrally from the first surface of the flexible base while excess resin forms at least part of the flexible base of the product;
- solidifying the resin;
- stripping the solidified resin from the peripheral surface of the mold roll.
29. The method of claim 27, wherein the step of forming engageable heads comprises deforming distal ends of the stems extending from the first and second surfaces to form the fastener elements.
30. The method of claim 29, wherein deforming distal ends of the stems comprises deforming distal ends of stems extending from one of the first and second surfaces, then deforming distal ends of stems extending from the other of the first and second surfaces.
31. The method of claim 30, wherein deforming distal ends of the stems comprises deforming distal ends of stems extending from one of the first and second surfaces at a first deformation location, then deforming distal ends of stems extending from the other of the first and second surfaces at a second deformation location that is spaced from the first deformation location.
32. The method of claim 31, wherein at least one of the first and second deformation locations comprise a gap formed between opposing rolls.
33. The method of claim 29, wherein deforming distal ends of the stems forms fastener elements having heads that extend laterally from the stems in multiple directions.
34. The method of claim 27, wherein the step of molding comprises
- continuously introducing molten resin to a gap defined between peripheral surfaces of a pair of rotating mold rolls each having an array of cavities for forming the stems, the cavities extending inwardly from respective mold roll peripheries, such that the resin at least partially fills the cavities to form stems extending from the first surface and the opposite, second surface of the flexible base while excess resin forms the flexible base of the product;
- solidifying the resin;
- stripping the solidified resin from the peripheral surfaces of the mold rolls.
35. The method of claim 27, wherein the step of molding comprises molding a first fastener preform and a second fastener preform, each of the fastener preforms including a base layer and an array of fastener element stems extending integrally therefrom.
36. The method of claim 35 comprising permanently affixing respective faces of the first and second fastener preforms in an opposing relationship forming the flexible base.
37. The method of claim 36, wherein the step of affixing comprises adhering the faces with adhesive.
38. The method of claim 37, wherein the step of affixing comprises introducing the first and second fastener preforms to a nip.
39. The method of claim 27, wherein at least one of the first and second fields of stems comprise one or more discrete regions of stems.
40. The method of claim 27, wherein stems extending from at least one of the first and second surfaces are arranged in a band with a region adjacent the band free of the stems.
41. The method of claim 40, wherein the stems extending from at least one of the first and second surfaces are arranged in multiple, spaced-apart bands.
42. The method of claim 27, wherein the fastener elements include heads that extend laterally from stems in multiple directions.
43. The method of claim 27, wherein the fastener elements include heads that extend laterally from stems in one or more discrete directions.
44. The method of claim 27, wherein the plastic resin comprises a degradable material.
45. The method of claim 44, wherein the degradable material is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
46. The method of claim 44, wherein the plastic resin complies with ASTM D6400-99.
47. The method of claim 27 further comprising introducing a degradable plastic additive to the plastic resin prior to molding.
Type: Application
Filed: Apr 5, 2004
Publication Date: Oct 6, 2005
Inventor: Christopher Gallant (Nottingham, NH)
Application Number: 10/818,649