U.S. patent application number 10/039139 was filed with the patent office on 2002-05-16 for touch fastener with magnetic attractant.
This patent application is currently assigned to Velcro Industries B.V.. Invention is credited to Jacobs, Martin I., Kenney, Randall B., Routhier, Brian J..
Application Number | 20020058123 10/039139 |
Document ID | / |
Family ID | 23544312 |
Filed Date | 2002-05-16 |
United States Patent
Application |
20020058123 |
Kind Code |
A1 |
Kenney, Randall B. ; et
al. |
May 16, 2002 |
Touch fastener with magnetic attractant
Abstract
A fastening component of a separable fastener has some portion
that is necessary for its fastening function, such as the hooks,
the base to which the hooks are attached or a substrate that is
used for another purpose, comprised of a magnetically attractive
constituent. Another portion of the fastening component is
comprised of a magnetically inert constituent. The fastening
element may be the hook portion or the loop portion of a typical
fastener. The fastening elements and the base may be unitary, or of
different precursors, such as in a woven fastener component. The
magnetically inert constituent may comprise a polymeric plastic or
a thermoplastic elastomer. The magnetic attractant may impregnate
the magnetically inert constituent, or it may coat or be coated by
the magnetically inert constituent. The magnetic attractant may
comprise a metal powder. The metal may be selected from the group
consisting of iron powder. The magnetic attractant may be an
organo-iron or a rare earth metal. In a woven fastener, either the
base structure or the hooks may include the magnetic attractant, or
both may do so. The material that forms the hooks may be entirely
of a magnetically attractive material, with the material that forms
the woven base being magnetically inert. Rather than the
magnetically attractive material being incorporated into the
fastening elements or the base, it may be incorporated into the
substrate that is formed from a precursor element that is separate
from the base, and that is joined to the base.
Inventors: |
Kenney, Randall B.;
(Concord, NH) ; Routhier, Brian J.; (Washington,
DC) ; Jacobs, Martin I.; (Fort Washington,
PA) |
Correspondence
Address: |
STEVEN J WEISSBURG
238 MAIN STREET
SUITE 303
CAMBRIDGE
MA
02142
|
Assignee: |
Velcro Industries B.V.
Castorweg 22 - 24 P.O. Box 155
Curacao
NL
|
Family ID: |
23544312 |
Appl. No.: |
10/039139 |
Filed: |
December 31, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10039139 |
Dec 31, 2001 |
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09680607 |
Oct 6, 2000 |
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09680607 |
Oct 6, 2000 |
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09365273 |
Jul 30, 1999 |
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09365273 |
Jul 30, 1999 |
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09035225 |
Mar 5, 1998 |
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09035225 |
Mar 5, 1998 |
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08390876 |
Feb 17, 1995 |
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Current U.S.
Class: |
428/99 ;
264/173.1; 264/173.17; 428/100; 428/900 |
Current CPC
Class: |
Y10T 428/24182 20150115;
B29C 48/355 20190201; B29C 48/07 20190201; B29C 2043/465 20130101;
Y10S 428/90 20130101; B29C 48/0014 20190201; B29C 48/12 20190201;
Y10T 24/2792 20150115; Y10T 24/27 20150115; B29C 48/21 20190201;
B29L 2031/729 20130101; B29C 48/08 20190201; Y10T 24/2783 20150115;
B29C 33/16 20130101; Y10T 428/24008 20150115; B29C 48/13 20190201;
A44B 18/0076 20130101; Y10T 428/24017 20150115; A44B 18/0049
20130101; A44D 2203/00 20130101 |
Class at
Publication: |
428/99 ; 428/100;
428/900; 264/173.1; 264/173.17 |
International
Class: |
B32B 003/06; B29C
047/06 |
Claims
Having described the invention, what is claimed is:
1. A component of a two component separable fastener, said
component comprising: a. a base; and b. carried on said base, a
plurality of fastening elements; wherein at least one of said base
and said fastening elements comprise a magnetically inert
constituent that is intimately associated with a magnetic
attractant constituent.
2. The component of claim 1, said magnetically inert constituent
comprising a polymeric plastic.
3. The component of claim 2, said plastic comprising a
thermoplastic.
4. The component of claim 2, said plastic comprising a
thermoplastic elastomer.
5. The component of claim 1, wherein said magnetic attractant
impregnates said magnetically inert constituent.
6. The component of claim 1, wherein said magnetic attractant coats
said magnetically inert constituent.
7. The component of claim 1, wherein said magnetic attractant is
coated with said magnetically inert constituent.
8. The component of claim 1, wherein said fastening elements
comprise hook-like elements.
9. The component of claim 1, wherein said fastening elements
comprise loop-like elements.
10. The component of claim 1, wherein said magnetic attractant
comprises a metal powder.
11. The component of claim 1, wherein said fastening elements
comprise a magnetically inert constituent that is intimately
associated with a magnetic attractant.
12. The component of claim 1, wherein said base comprises a
magnetically inert constituent that is treated with a magnetic
attractant.
13. The component of claim 1, wherein said base and said fastening
elements comprise the same constitutive materials.
14. The component of claim 1, wherein said fastening elements and
said base are formed unitarily from the same precursor element.
15. The component of claim 1, further comprising a substrate that
is formed from a precursor element that is separate from said base,
and that is joined to said base.
16. The component of claim 15, wherein said fastening elements and
said substrate are coextruded.
17. The component of claim 15, wherein said substrate and said
fastening elements are laminated together.
18. The component of claim 17, wherein said substrate comprises a
woven material.
19. The component of claim 17, wherein said substrate comprises a
non-woven material.
20. The component of claim 17, wherein said substrate comprises
paper.
21. The component of claim 17, wherein said substrate comprises
foam.
22. The component of claim 1, wherein said fastening elements
comprise filaments that have been woven into said base.
23. The component of claim 22, said fastening element filaments
comprising polymeric monofilaments.
24. The component of claim 2, said polymeric plastic selected from
the group consisting of: polypropylene, polyethylene, polyamide,
polyester, polystyrene, polyvinyl chloride, acetal, acrylic,
polycarbonate, polyphenylene oxide, polyurethane and
polysulfone.
25. The component of claim 1, said magnetic attractant comprising a
ferro-magnetic material.
26. The component of claim 1, said magnetic attractant being
selected from the group consisting of iron powder, magnetite iron
oxide, hematite iron oxide, iron(II) oxide, iron (III) oxide,
iron(III) stearate.
27. The component of claim 1, said magnetic attractant comprising
an organo-iron compound.
28. The component of claim 1 said magnetic attractant comprising a
rare earth metal.
29. The component of claim 15, said substrate comprising a magnetic
attractant.
30. A molded article comprising: a. a body molded from a molding
material, said body having at least one surface and an interior
body region; b. fixed to said surface of said molded body, a
separable fastener component for use with a complementary separable
fastener component, said separable fastener component comprising:
i. a base; and ii. carried on said base, a plurality of fastening
elements; wherein at least one of said base and said fastening
elements comprise a magnetically inert constituent that is
intimately associated with a magnetic attractant constituent.
31. The molded article of claim 30, said magnetically inert
constituent comprising a polymeric plastic.
32. The molded article of claim 31, said plastic comprising a
thermo plastic.
33. The molded article of claim 31, said plastic comprising a
thermoplastic elastomer.
34. The molded article of claim 31, said polymeric plastic selected
from the group consisting of: polypropylene, polyethylene,
polyamide, polyester, polystyrene, polyvinyl chloride, acetal,
acrylic, polycarbonate, polyphenylene oxide, polyurethane,
polysulfone and thermoplastic elastomers.
35. The molded article of claim 30, said magnetic attractant
comprising a ferro-magnetic material.
36. The molded article of claim 30, said magnetic attractant being
selected from the group consisting of iron powder, magnetite iron
oxide, hematite iron oxide, iron(II) oxide, iron (III) oxide,
iron(III) stearate.
37. The molded article of claim 30, said magnetic attractant
comprising an organo-iron compound.
38. The molded article of claim 30 said magnetic attractant
comprising a rare earth metal.
39. The molded article of claim 30, wherein said fastening elements
comprise a magnetically inert constituent that is treated with a
magnetic attractant.
40. The molded article of claim 30, further comprising a substrate
that is joined to said base.
41. A component of a two component separable fastener, said
component comprising: a. a base; b. carried on said base, a
plurality of fastening elements; and c. joined to said base, a
substrate; wherein said substrate comprises a magnetically inert
constituent that is intimately associated with a magnetic
attractant constituent.
42. The component of claim 41, said magnetically inert constituent
comprising a thermoplastic.
43. The component of claim 41, said magnetically inert constituent
comprising a thermoplastic elastomer.
44. The component of claim 41, wherein said magnetic attractant
impregnates said magnetically inert constituent.
45. The component of claim 41, wherein said magnetic attractant
comprises a metal powder.
46. A method of making a component of a two component separable
fastener, said method comprising the steps of: a. providing a
magnetic attractant; b. associating said magnetic attractant with
at least one of a base and a plurality of fastening elements
carried on said base; and wherein at least one of said base and
said fastening elements comprise a magnetically inert constituent
that is intimately associated with said magnetic attractant.
47. The method of claim 46, wherein said step of associating said
magnetic attractant comprises the step of associating said magnetic
attractant with said plurality of fastening elements.
48. The method of claim 46, wherein said step of associating said
magnetic attractant comprises the step of associating said magnetic
attractant with said base.
49. The method of claim 46, wherein said step of associating said
magnetic attractant comprises the step of mixing a polymeric
plastic resin with a magnetic attractant.
50. The method of claim 47, wherein said mixing step comprises the
step of mixing said plastic resin with a magnetic attractant
selected from the group consisting of iron, powder, magnetite iron
oxide, hematite iron oxide, iron(II) oxide, iron (III) oxide,
iron(III) stearate.
51. The method of claim 46, further comprising the step of joining
said base to a substrate.
52. A method for making a molded article, said method comprising
the steps of: a. making a component of a two component separable
fastener according to the steps comprising: i. providing a magnetic
attractant; ii. associating said magnetic attractant with at least
one of a base and a plurality of fastening elements carried on said
base; and wherein at least one of said base and said fastening
elements comprise a magnetically inert constituent that is
intimately associated with said magnetic attractant. b. placing
said separable fastener component into a mold, with said fastening
face facing a wall of said mold, said mold comprising: i. a
fastening element receiving valley region; ii. a magnet inside a
mold wall adjacent said fastening element receiving valley; whereby
said magnet attracts said fastener component toward said mold wall;
and c. providing molding material to said mold.
53. The method for making a molded article of claim 52, wherein
said step of associating said magnetic attractant comprises the
step of associating said magnetic attractant with said plurality of
fastening elements.
54. The method for making a molded article of claim 51, wherein
said step of associating said magnetic attractant comprises the
step of associating said magnetic attractant with said base.
55. The method for making a molded article of claim 52, wherein
said step of associating said magnetic attractant comprises the
step of mixing a polymeric plastic resin with a magnetic
attractant.
56. The method for making a molded article of claim 52, wherein
said mixing step comprises the step of mixing said plastic resin
with a magnetic attractant selected from the group consisting of
iron, powder, magnetite iron oxide, hematite iron oxide, iron(II)
oxide, iron (III) oxide, iron(III) stearate.
57. The method for making a molded article of claim 52, further
comprising the step of joining said base to a substrate.
Description
BACKGROUND
[0001] The present invention relates to touch fasteners in general,
and more specifically, to touch fasteners for incorporation by
molding into molded articles.
[0002] Hook and loop type separable touch fasteners, such as those
sold by the assignee of this application under the trademark
Velcro, are well-known and are used to join two members detachably
to each other. This type of fastener has two components. Each has a
flexible substrate material having one component of the fastening
system on a fastening surface thereof. One component is typically
comprised of resilient hooks while the other is comprised of loops,
and when the two surfaces are pressed together they interlock to
form a releasable engagement.
[0003] Separable fasteners are used in the manufacture of
automobile seats in the attachment of an upholstered seat cover to
a polyurethane foam bun. One portion of the separable fastener is
incorporated onto the surface of the polyurethane foam bun during
the foam molding process. The mating portion of the separable
fastener is attached to the seat cover to provide releasable
attachment to the foam bun The separable fastener assembly used in
the foam mold for incorporation in the bun surface typically
comprises the hooked portion of a separable fastener. This hook
portion is characterized by a base carrying resilient hooks on a
fastening surface. The opposite, non-fastening surface of the base
may carry anchor projections to become incorporated into the foam
to provide stable attachment of the separable fastener assembly to
the foam article. It is also common for a backing layer or
substrate to mate with the non-fastening face of the base. The
substrate may be of a material that is more conducive to handling,
of the component or its adherence to other articles. Anchor
projections may also project from the substrate. Further, other
components can be sandwiched between the substrate and the
base.
[0004] A protective layer, such as a thin plastic film, may be
placed over the resilient hooks, to prevent incursion of foam into
the hooks during the molding process, since significant foam
contamination of the hooks would affect their ability to engage
with the mating portion of the fastener attached to the seat cover.
Alternatively, an elastomeric cover that intimately surrounds the
hooks, except for a small portion at their tips, can also be used.
After the molded article is fabricated and removed from the mold,
the elastomeric material is removed.
[0005] In some assemblies, a magnetically attractive shim is
attached to the base to facilitate placement of the assembly in a
valley (also known as a trench or trough) of the mold cavity wall,
which is equipped with magnets. The shim also helps secure the
hook-carrying face of the component tightly against the mold wall,
thereby further minimizing incursion of the foam into the hooks.
The assemblies may be referred to as "mold-in" fasteners or
assemblies, due to their use in such molded products.
[0006] The shim can be incorporated into different locations in the
assembly. It can be sandwiched between the hook carrying base and a
substrate or backing layer, either temporary or permanent. It can
be located centrally relative to the width of the hook-carrying
base, or along its marginal edges. In cases where a thin plastic
film is used to cover the hooks, the shim can be sandwiched between
the plastic sheet and the hooks.
[0007] As mentioned above, it is also known to substantially cover
the hook region with an elastomeric material that protects the
hooks against incursion of the foam. It is known to include a
magnetic attractant in this elastomeric material.
[0008] Known methods of adhering the protective film cover to the
hook-carrying component include to use a long bead of hot melt
adhesive there between. It is also known to include a magnetic
attractant in this hot melt material.
[0009] The known methods all have drawbacks. With regard to the
metal shim itself, it presents an extra component and an extra
manufacturing step, thereby contributing to the cost of the
assembly and the time for manufacturing a given length of material.
The metal shim also contributes to the weight of the material. In
the construction process, care must be taken that workers are not
cut by the metal strips. The metal limits the flexibility of the
strip, and consideration must be taken of the thermal expansion and
contraction properties of the various binders and additional layers
that might be used to secure the strip to the substrate. The metal
strip also curls and bows and generally makes handling the
component unwieldy.
[0010] Considering those known assemblies that use either the
protective plastic or the elastomeric cover to contain the metal
shim, or a magnetic attractant, there are reasons to eliminate
these protective covers, if possible. The protective covers also
entail additional steps, in their manufacture, attachment to the
fastener assembly, and removal from the fastener assembly after
molding. All protective material must be removed from the hooks (or
loops, if it be the loop carrying component molded into the
article), or else the hooks (or loops) will not be exposed to
fasten to the mating component. These extra steps must typically be
conducted away from a normal high speed production line and
contribute to the cost of the fastener assembly, the time for its
manufacture, and also generate a relatively large volume of
essentially waste material. Additionally, sometimes a residue from
the cover material remains on the fastening component after
removal, which is undesirable.
[0011] Thus, there is a great need for a touch fastener assembly
that can be molded into a molded product, without the use of metal
shims or protective covering for the fastener components. There is
also a need to simplify the manufacture of such mold-in assemblies,
to minimize their cost, production time, and the time to prepare
the molded product for use. It is thus an object of the invention
to facilitate a simple means for providing a magnetic
attractability to the mold-in fastener assembly. It is another
object of the invention to provide a light weight mold-in assembly
that does not require a metal shim or protective covering for the
fastener components, such as hooks.
SUMMARY
[0012] A preferred embodiment of the invention is a fastening
component of a separable fastener, where some portion of the
fastening component that is absolutely necessary for its fastening
function, such as the hooks, the base to which the hooks are
attached or a substrate that is used for another purpose, is
comprised of a magnetically attractive constituent, and where
another portion of the fastening component is comprised of a
magnetically inert constituent. Either the hook portion or the loop
portion of a typical fastener may include the magnetically
attractive constituent.
[0013] A preferred embodiment of the invention is thus a component
of a two component separable fastener, said component comprising a
base; and carried on said base, a plurality of fastening elements;
wherein at least one of said base and said fastening elements
comprise a magnetically inert constituent that is intimately
associated with a magnetic attractant constituent. The fastening
elements and the base may be unitary, such as in the case of an
extruded component, or they may be of different precursors, such as
in the case of a woven fastener component.
[0014] The magnetically inert constituent may comprise a polymeric
plastic or a thermoplastic elastomer, including but not limited to
polypropylene, polyethylene, polyamide, polyester, polystyrene,
polyvinyl chloride, acetal, acrylic, polycarbonate, polyphenylene
oxide, polyurethane and polysulfone.
[0015] The magnetic attractant may impregnate the magnetically
inert constituent, or it may coat or be coated by the magnetically
inert constituent.
[0016] The fastening elements may comprise hook-like elements or
loop-like elements.
[0017] The magnetic attractant may comprise a metal powder. The
metal may be selected from the group consisting of iron powder,
magnetite iron oxide, hematite iron oxide, iron(II) oxide, iron
(III) oxide, iron(III) stearate. The magnetic attractant may also
be an organo-iron compound or a rare earth metal.
[0018] In the case of a woven fastener, either the base structure
or the hooks may include the magnetic attractant, or both may do
so. Further, the material that forms the hooks may be entirely of a
magnetically attractive material, with the material that forms the
woven base may be magnetically inert.
[0019] The fastener may also include a substrate, that is formed
from a precursor element that is separate from said base, and that
is joined to said base. The fastening elements and the substrate
may be coextruded or formed separately and laminated together. The
substrate may be of a woven, non-woven, paper or foam material.
[0020] The fastening elements may comprise polymeric
monofilaments.
[0021] Another preferred embodiment of the invention is a molded
article comprising a body molded from a molding material, said body
having at least one surface and an interior body region, fixed to
said surface of said molded body, a separable fastener component
for use with a complementary separable fastener component, said
separable fastener component being according to any of the
variations described above.
[0022] Another preferred embodiment of the invention is a component
of a two component separable fastener, the component comprising a
base and carried on the base, a plurality of fastening elements
and, joined to the base, a substrate, where the substrate comprises
a magnetically inert constituent that is intimately associated with
a magnetic attractant constituent.
[0023] The magnetically inert constituent may be as described
above, with respect to the embodiment where the magnetic attractant
is associated with either the fastening elements or the base. The
magnetically attractive constituent may also be any of the
magnetically attractive materials identified above.
[0024] Yet another preferred embodiment of the invention is a
method of making a component of a two component separable fastener,
the method comprising the steps of providing a magnetic attractant
and associating said magnetic attractant with at least one of a
base and a plurality of fastening elements carried on said base;
wherein at least one of said base and said fastening elements
comprise a magnetically inert constituent that is intimately
associated with said magnetic attractant.
[0025] The magnetic attractant may be associated with the base
only, or the fastening elements only, or both. A polymeric plastic
resin may be mixed with a magnetic attractant such as identified
above. The polymeric plastic resin may be such as is identified
above.
[0026] According to still another preferred embodiment, the
invention is a method for making a molded article, said method
comprising the steps of making a component of a two component
separable fastener, such as identified above, having a magnetic
attractant intimately associated therewith, according to the
methods identified above. The fastening component is then placed
into a mold, with its fastening face facing a wall of said mold,
said mold comprising: a fastening element receiving valley region
and a magnet inside a mold wall adjacent said fastening element
receiving valley, whereby said magnet attracts said fastener
component toward said mold wall. Molding material is provided to
said mold to mold the product with the fastening component
incorporated therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] These and other features, aspects, and advantages of the
present invention will become better understood with regard to the
following description, appended claims and accompanying drawings,
where:
[0028] FIG. 1 is a schematic perspective view of a fastening
component of the invention, where the fastening elements are
hook-type elements.
[0029] FIG. 2 is a cross-sectional side view of a mold for use with
the invention, having a cavity for insertion of the fastening
component and a magnet within the mold walls, also showing a
fastening component of the invention in place in the mold for
molding.
[0030] FIG. 3 is a cross-sectional view similar to that shown in
FIG. 2, where the mold-in product has hooks and anchors
back-to-back.
[0031] FIG. 4 shows, schematically, the mold of FIG. 3, with
molding material being poured into the mold.
[0032] FIG. 5 shows, schematically, the molding material curing in
the mold shown in FIG. 4.
[0033] FIG. 6 shows, schematically, a molded product including a
fastening component of the invention, either a single sided
fastener, or an anchored back-to-back fastening component.
[0034] FIG. 7 shows schematically an apparatus and process for
manufacturing an embodiment of the fastener component of the
invention, having a unitary molded base carrying hooks on one
surface thereof.
[0035] FIG. 8 shows schematically an apparatus and process for
manufacturing an embodiment of the fastener component of the
invention, having a substrate and hooks which are co-extruded and
then laminated together.
[0036] FIG. 9 shows schematically a fastening component of the
invention having a unitary molded base carrying hooks on one
surface thereof, laminated with a separate substrate.
[0037] FIG. 10 shows schematically an apparatus and process for
manufacturing an embodiment of the fastener component of the
invention, having a unitary molded base carrying hooks on one
surface thereof, which is further laminated with a substrate of a
different material.
[0038] FIG. 11 shows schematically an embodiment of the invention,
having a magnetically attractive loop carrying fastener
component.
DETAILED DESCRIPTION
[0039] A fastening component 100 of the invention is shown
schematically with reference to FIG. 1. A base 110 has two
surfaces: a fastening surface 112 and a non-fastening surface 114.
The base may be woven, non-woven, plastic, fabric or any other
suitable structure or material. The invention is not limited to the
mechanical form of the base, and any known mechanical form of base
for separable touch-type fasteners is believed to be consistent
with the invention. Often, the base is a plastic base and it is
attached to a separate substrate of a different material. If the
base is a woven structure, the base portion may be referred to as a
"ground fabric." The base presents on its fastening surface 112, a
plurality of hook-type elements 116. The hook-type elements may be
shaped as hooks, or mushrooms or two tined anchors, or any other
mechanical form of hook-type element used for separable touch-type
fasteners, which engage loop-type elements, as is known in the art.
Such elements are referred to herein as "hook-type", or "hook-like"
or "hook" elements, whether or not they are in the shape of hooks.
Any known mechanical form, and any as yet unknown mechanical form
of hook elements is believed to be consistent with the
invention.
[0040] According to the present invention, either the fastening
elements 116 (hooks, as shown in the figure) or the base 110, or
both, include a magnetically attractive constituent. As shown in
FIG. 2, the fastening component 100 is used in a mold 221, having a
main mold wall 220 surrounding a main cavity 224. A fastening
element-receiving mold valley 222 is in the bottom wall 228 of the
mold. Embedded in the bottom wall 228 is a magnet 226, such as is
known in the art.
[0041] The fastening component 100 is inserted into the mold,
adjacent the fastening element-receiving valley 222, with the hooks
116 facing into the valley 222. The magnet 226 attracts the
fastening component 100 toward the bottom mold wall 228, due to the
magnetically attractive material contained in the fastening
component 100. The magnetic attraction secures the fastening
component to the mold wall, thereby preventing the incursion of the
molding material among the fastening elements.
[0042] In addition to the magnetic attractant, other techniques can
and are typically used to prevent the fouling of the fastening
elements with the molding material. Any such structures known to
the art, and any such structures yet to be developed, are believed
to be consistent with the invention. For instance, a film strip can
completely cover the fastening elements, such as is shown in U.S.
Pat. No. 4,693,921, issued in 1987 to Billarant, entitled FASTENING
TAPE DESIGNED TO BE ATTACHED TO A MOLDED ARTICLE DURING MOLDING,
AND ITS ATTACHING METHOD. Rather than covering the entire surface
of the fastening elements, strips of film can border the fastening
element region, forming gaskets to prevent the incursion of film.
Such film regions are shown in U.S. Pat. No. 4,726,975, issued in
1988 to Hatch, entitled METHOD AND APPARATUS FOR ADAPTING SEPARABLE
FASTENERS FOR ATTACHMENT TO OTHER OBJECTS. Also possible is to use
an elastomeric covering that intimately (either completely, or
partially) surrounds the fastening elements, such as is described
in U.S. Pat. No. 5,286,431 (for fully surrounding), issued to
Banfield et al. in 1994, entitled MOLDED PRODUCT HAVING INSERT
MOLD-IN FASTENER or, (for partially surrounding) as shown in PCT
application No. PCT/US94/07473 for HOOK AND LOOP TYPE INSERT USED
IN MOLDING PROCESS, published Jan. 19, 1995, corresponding to U.S.
patent application Ser. No. 08/087,917, filed on Jul. 6, 1993,
entitled DIE CUT MOLD-IN. All of the foregoing patents and
applications are hereby incorporated herein by reference.
[0043] Another possibility is to use a fastening component, for
instance having hook-type fastening elements, that has a pattern of
hooks with a main central region, circumscribed by a bald region
that is substantially free of hooks, which is itself circumscribed
by a perimeter region of hooks. The fastening element is used with
a mold having a central valley, surrounded by a perimeter land,
which is in turn typically surrounded by a perimeter valley. The
perimeter valley mates with the perimeter region of hooks; the land
mates with the bald region; and the central mold valley mates with
the central main region of hooks. The perimeter region of hooks may
be partially fouled by the incursion of foam material, however, the
main, central region of hooks is not fouled, being protected by the
"sacrificial" perimeter hooks. Such an arrangement is described in
co-pending, co-assigned U.S. Ser. No. ______, filed of even date
herewith, in the names of Brian J. Routhier, Martin I. Jacobs and
George A. Provost, entitled SEPARABLE FASTENER HAVING A BALD
PERIMETER RIB BOUNDED BY FASTENING ELEMENTS, which is incorporated
fully herein by reference.
[0044] The molding process is shown schematically in FIGS. 3, 4, 5
and 6, for incorporating an embodiment of the fastener of the
invention that is a back-to-back hook and anchor fastener into a
molded product. The fastener component 300 is inserted into the
main cavity 324 of the mold 321, with its fastening elements 316
facing the fastening element receiving valley 322 and its anchoring
elements 334 facing the central region of the main mold cavity 324.
The magnet 326 attracts the fastening component 300 toward the
magnet 326, thereby enhancing the sealing of the fastening
component to the mold wall 328. This helps to prevent fouling of
the hook components 316 during the molding process.
[0045] The next step in the molding process is shown schematically
in FIG. 4, where the molding material 410 is introduced into the
mold. The molding material may constitute a single component, or
there may be multiple components that are mixed as they are
introduced into the mold, or before.
[0046] The article being formed 524 is shown schematically in FIG.
5. The anchor elements 334 are surrounded by the molding material,
thereby embedding the fastening component into the molded article.
It is not necessary that anchoring elements be used, and there are
many ways known to the art that do not use them. FIG. 5 is intended
to show both anchored and unanchored embodiments. A molded article
524 incorporating the magnetically attractive fastening component
300 with exposed hook components 316 is shown schematically in FIG.
6. The optional anchoring elements 334 are shown in phantom,
embedded in the molded material. A typical type of molded article
is a foam seat cushion, such as for an automobile or airplane.
Rather than foam, other types of molded materials are also
suitable.
[0047] In a typical embodiment of the invention, the hook elements
116 and the base 110 are molded unitarily from the same precursor
element as one mechanical element, and are thus composed of the
same material. Suitable such materials include: polymeric plastics
such as: polypropylene, polyethylene, polyamide, polyester,
polystyrene, polyvinyl chloride, acetal, acrylic, polycarbonate,
polyphenylene oxide, polyurethane, polysulfone, and thermoplastic
elastomers. Suitable magnetic attractants include: all
ferro-magnetic materials, such as iron (powder), iron oxide
(various forms, including magnetite, hematite, iron(II) oxide, iron
(III) oxide), iron(III) stearate (and various organo-iron
compounds), rare earth metals and their compounds.
[0048] An apparatus for molding a fastening component having
unitarily molded fastening elements and base is shown schematically
in FIG. 7. This apparatus is of the type shown generally in U.S.
Pat. No. 4,794,028, entitled METHOD FOR CONTINUOUSLY PRODUCING A
MULTI-HOOK FASTENER MEMBER AND PRODUCT OF THE METHOD, issued in
1988 to Fischer; U.S. Pat. No. 4,872,243, entitled MULTI-HOOK
FASTENER MEMBER, issued in 1989 also to Fischer; and U.S. Pat. No.
4,775,310, entitled APPARATUS FOR MAKING A SEPARABLE FASTENER
issued in 1988 also to Fischer. All three patents are incorporated
herein by reference. An extruder barrel 701 melts and forces molten
plastic 703 through a die 702, into the nip 706 between a base
roller 704 and a cavity roller 705, that contains cavities 711 to
form the hooks 716 of a strip fastener 700, which extend from a
web-like base 710 composed of the same material as is the hooks
716. The strip fastener material formed at the nip 706 travels
around the periphery of the cavity roller 705 and around the
stripping roller 713, which assists in pulling the formed hook
sheet from engagement with the cavity roll 705. The strip is then
passed to a wind-up roll, not shown.
EXAMPLES
[0049] In a first example, molded hooks, of the type known as
Velcro Ultra 8 brand hooks sold by Velcro Group corporation of
Manchester, N.H., were molded using the unitary continuous forming
method, such as shown in FIG. 7, also described in the above cited
U.S. Pat. Nos. 4,794,028, 4,872,243 and 4,775,310 to Fischer. The
material provided to the extruder was 40% (all percentages are by
weight) Impet brand (polyethylene terephthalate PET) resin premixed
with ferro-magnetic filler, sold by the Hoechst Celanese Company of
Chatham, N.J., grade EKX-155, blended with 60% Vandar brand
(polybutylene terephthalate PBT) resin also sold by Hoechst grade
MB90011A1. The processing temperatures ranged from 530.degree. F.
in the feed section of the extruder to 570.degree. F. at the die.
The temperature of the base roll was 104.degree. F., the cavity
roll 191.degree. F. and the stripping roll was 83.degree. F.
[0050] In a second example, molded hooks, of the same type, were
again molded using the unitary continuous forming method such as
shown in FIG. 7. The material provided to the extruder was 40%
Celcon brand (acetal) resin with ferromagnetic filler, sold by the
Hoechst, grade MM3.5H blended with 60% Celcon brand (acetal) resin
also sold by Hoechst, grade TX90 PLUS. The processing temperatures
ranged from 360.degree. F. in the feed section of the extruder to
375.degree. F. at the die. The temperature of the base roll was
105.degree. F., the cavity roll 195.degree. F. and the stripping
roll was 85.degree. F.
[0051] It is also possible, as is well known, for the hook elements
to be unitarily molded with a base and for a web-like substrate to
be manufactured from separate mechanical precursor elements, which
are subsequently or simultaneously joined. For instance, the hook
elements with base and the substrate can be co-extruded according
to any known method; such as by a cross-head die or by calendaring
two separate extrusion streams together. In such a case, either the
hooks with base, or the substrate alone, or both together can
include the magnetic attractant. They may be of identical
materials, or different.
[0052] An apparatus for molding a fastening component having
coextruded fastening elements with a base and a substrate is shown
schematically in FIG. 8. This apparatus is similar to that shown
above with reference to FIG. 7, but uses a cross-head die. Molten
plastic 803h (for hooks and base) and 803s (for substrate) is
forced through a cross-head coextrusion die head 802, with two
different die orifices 807h and 807s. The two streams of molten
plastic are forced into the nip 806 between a base roller 804 and a
cavity roller 805, that contains cavities 811 to form the hooks 816
of a strip fastener 800. A pool of hot hook material P.sub.h forms
upstream of the nip, as well as a pool of hot second substrate
material P.sub.s. At the nip, the hook material is forced into the
cavities 811 in the hook roller 805. Simultaneously, the substrate
material is flattened and spread into a web shape, along with a
quantity of the hook material (which forms a base unitarily with
the hooks being formed). The pressure in the nip joins the hook
material and base, on the one hand, with the substrate material, on
the other hand such that the hooks 816 and the substrate 830 are
formed, and joined to become the fastener component 800. This
coextruded component travels around the hook roller 805, and is
stripped therefrom in the same manner as is a simple extruded
unitary hook and base component, shown in FIG. 7. The strip is then
passed to a wind-up roll, not shown.
[0053] Rather than a single sided hook component, as shown in FIG.
8, a back-to-back hook and anchor fastening component can be
coextruded as shown in FIG. 8, with the anchor material being in
place of the substrate material. In such a case, the base roller
804 includes anchor cavities around its periphery. An apparatus for
making such a structure is shown in U.S. patent application Ser.
No. 381,632, filed on Jan. 31, 1995, entitled BACK-TO-BACK HOOK
FASTENER, which is a divisional application of U.S. patent
application Ser. No. 92,312, filed on Jul. 14, 1993, and in a
corresponding published PCT application, PCT/US94/07556, filed on
Jul. 6, 1994 and published on Jan. 19, 1995 all of which are
assigned to the assignee hereof, and all of which are incorporated
herein by reference.
[0054] An article that could have been made with the equipment
shown in FIG. 8 is shown schematically in FIG. 9. The hooks 916 are
composed of a first material. A base 910 is unitary with the hooks,
having been extruded therewith. The substrate 930 is composed of
the same material, or a second, different material. The joining
region, which may take many different physical forms, exhibits a
transition from the hook material to the substrate material.
[0055] The substrate may be a woven or a non woven fabric.
[0056] It has already been discussed to use a unitary extrusion
from which are molded hooks and a unitary base, as well as a
coextrusion, which joins a base with hooks to a substrate. Other
methods may be used for joining hooks to a substrate. Another
method is to laminate an already formed substrate to a unitary hook
and base, as the hook carrying web is being extruded and formed.
This technique is described generally in U.S. Pat. No. 5,260,015,
issued Nov. 9, 1993, entitled METHOD FOR MAKING A LAMINATED HOOK
FASTENER, in the name of William J. Kennedy et al., which is
incorporated herein by reference. This method may be referred to as
the "one-wrap" method. The apparatus for implementing the method is
shown schematically in FIG. 10. As with the embodiment shown in
FIG. 7, an extruder barrel 1001 melts and forces molten plastic
1003 through a die 1002, into the nip 1006 between a base roller
1004 and a cavity roller 1005, that contains cavities 1011 to form
the hooks 1016 of a strip fastener 1000, which extend from a
web-like base 1010 composed of the same material as is the hooks
1016. The strip fastener material formed at the nip 1006 travels
around the periphery of the cavity roller 1005 and around the
stripping roller 1013, which assists in pulling the formed hook
sheet from engagement with the cavity roll 1005. The strip is then
passed to a wind-up roll, not shown.
[0057] A pre-formed sheet material 1030 is inserted into the nip
1006 to create the strip fastener tape. The sheet material bonds
intimately with the unitary base 1010 composed of hook material to
become an integral part of the structure of the strip fastener. A
set of pins 1017 may help to carry the sheet material in a flat
unwrinkled state. Other rollers and tensioning equipment 1019 are
used to maintain the proper tension and flatness on the sheet
material that will form the laminated substrate.
[0058] At the nip 1006, the sheet material 1030 is laminated to the
hook material, as indicated by the small half-circles downstream of
the nip. (The half-circles are not indicative of any circular
structure. They are simply used to identify what is typically a
flat sheet-like structure.)
[0059] A fastener strip formed by the apparatus shown in FIG. 10
may also be represented schematically by FIG. 9. Again, the hooks
916 and a unitary, base 910 are laminated to the sheet material 930
forming a second substrate. A transition region 950 is composed of
both the sheet material and the hook material.
[0060] There are many candidates for the sheet-like substrate
material. The material may be woven or non-woven. It may constitute
an open or a tight weave. It may be paper, with or without an
adhesive backing, or may constitute a thin sheet of foam. It can
also constitute the loop component of a normal hook and loop
fastener pair. Any one of the foregoing may be useful to enhance
the anchoring of the hook component into the article being molded.
The type of sheet material substrate to which the hooks are
laminated is not material to the invention. Any of these substrate
backing materials may be composed of a substantial portion that is
magnetically attractive. As such, the laminated backing material
would be attracted to the magnet in the mold, and would achieve the
goals of the invention.
[0061] The invention does not depend on the method by which the
hook elements or the substrate are manufactured. All that is
required is that one or the other or both can be treated with a
magnetic attractant, such that it can be attracted by the magnet in
the mold.
[0062] Rather than the "one-wrap" laminating method shown in FIG.
10, an off-line method can be used after the hook and base material
is formed alone, such as shown in FIG. 7. Afterward, two rolled
webs, one of hook carrying base material, the other of the
substrate, can be laminated together. At the same time, a third web
of a thin protective film can be applied to cover the hooks, to
protect them against intrusion of molding material. The film can be
secured to the hook carrying base, and/or substrate, depending on
their relative widths, ultrasonically, or by heat and pressure, or
adhesive.
[0063] Most of the foregoing discussion has focused on the hooks
being molded. However, this too is not required for the practice of
the invention. For instance, U.S. Pat. No. 2,717,437, issued in
1955 to George DeMestral, entitled VELVET TYPE FABRIC AND METHOD OF
PRODUCING SAME discloses a hook component, which is entirely woven,
from weft and warp threads and auxiliary warp threads. The
auxiliary warp threads are formed into loops, which are cut, to
form hooks. Typically, the auxiliary warp threads are made from a
monofilament plastic resin. This plastic resin can be composed of
the magnetic attractant, as discussed above. With such products,
the hook material may also be referred to as "pile yarn" and the
weft and warp threads, which compose the structure that serves as
the base, are referred to as the ground yarns, or fabric.
[0064] While the foregoing has focused on a plastic matrix material
as one constituent for either the hooks or the substrate, with a
magnetic attractant filler generally therethrough as another
constituent, other mechanical forms of magnetically attractive
articles are possible and within the contemplation of the
invention. For instance, either the hooks or the substrate can
comprise a magnetically attractive core material, which is coated
with or sheathed by a magnetically inert (non-attractive) material.
Conversely, the articles can comprise a magnetically inert
material, coated with a magnetically attractive material. All that
is required is that at least one of the fastening elements or the
substrate comprise a magnetically inert material that is in some
fashion intimately associated or treated with a magnetically
attractive material.
[0065] The foregoing discussion has generally considered that the
fastening component to be incorporated into the mold be the hook
carrying component. Although this is typical, it need not be the
case. Therefore, the loop carrying component can alternatively be
the portion of the fastener that is embedded in the molded article.
In such case, as shown in FIG. 11, the loop carrying component 1100
will be the component that will include the magnetically attractive
material. All of the discussion above applies to this embodiment
also. The loops 1116 may be made from a plastic resin impregnated
with a magnetically attractive powder, or any other suitable
magnetically attractive form.
[0066] Thus, the invention accomplishes many goals. It provides a
magnetically attractive fastening component, without a stiff,
unwieldy, costly, heavy, possibly dangerous metal shim. Production
times are kept low, because the magnetic attractant need not be
added as a separate step after the hooks (or loops) are made, being
provided at the time the hooks are made, in the normal way that the
hooks are made. The fastening elements, such as the hooks, perform
the dual functions of containing the magnetic attractant, and
fastening to the mating element. Waste is minimized. No off-line
steps are required to incorporate or remove the element containing
the magnetic attractant. There are no problems of incompatible
thermal properties engendered by the magnetically attractive
material.
[0067] The foregoing discussion should be understood as
illustrative and should not be considered to be limiting in any
sense. While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
spirit and scope of the invention as defined by the claims.
* * * * *