U.S. patent application number 14/181268 was filed with the patent office on 2015-08-20 for conformable booties, shoe inserts, and waterproof breathable socks containing an integrally joined interface.
This patent application is currently assigned to W. L. Gore & Associates, GmbH. The applicant listed for this patent is W. L. Gore & Associates, GmbH, W. L. Gore & Associates, Inc.. Invention is credited to John E. Bacino, Norman E. Clough, Orlando Collazo, Stane Nabernick, Franz J. Shelley, Heike Wolfrum, Alexander Zaggl.
Application Number | 20150230554 14/181268 |
Document ID | / |
Family ID | 52595471 |
Filed Date | 2015-08-20 |
United States Patent
Application |
20150230554 |
Kind Code |
A1 |
Bacino; John E. ; et
al. |
August 20, 2015 |
Conformable Booties, Shoe Inserts, and Waterproof Breathable Socks
Containing an Integrally Joined Interface
Abstract
Waterproof, breathable socks, booties, shoe inserts, and
footwear assemblies containing the shoe inserts are provided. The
booties and shoe inserts include a laminate of a seamless ePTFE
membrane and at least one textile. The bootie is conformable over a
range of sizes and shoe shapes, and may be shaped to fit numerous
sizes and shapes of asymmetrical shoe lasts. The bootie may shrink
to fit, or, alternatively, be stretched to fit, an asymmetrical
last having a desired size to form a shoe insert. Such a
conformable bootie eliminates the need to have multiple sizes of
shoe inserts correlating to particular shoe sizes. In embodiments
where the ePTFE is seamless and continuous, the shoe insert
eliminates the need for a waterproof seam tape, which is
conventionally used to make shoe inserts waterproof. Methods of
forming the socks, booties, and shoe inserts are also provided.
Inventors: |
Bacino; John E.;
(Landenberg, PA) ; Clough; Norman E.; (Landenberg,
PA) ; Collazo; Orlando; (Elkton, MD) ;
Nabernick; Stane; (Kranj, SI) ; Shelley; Franz
J.; (Oxford, PA) ; Wolfrum; Heike;
(Unterhaching, DE) ; Zaggl; Alexander;
(Feldkirchen-Westerham, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
W. L. Gore & Associates, GmbH
W. L. Gore & Associates, Inc. |
Putzbrunn
Newark |
DE |
DE
US |
|
|
Assignee: |
W. L. Gore & Associates,
GmbH
Putzbrunn
DE
W. L. Gore & Associates, Inc.
Newark
|
Family ID: |
52595471 |
Appl. No.: |
14/181268 |
Filed: |
February 14, 2014 |
Current U.S.
Class: |
2/239 |
Current CPC
Class: |
B32B 27/12 20130101;
B32B 2255/02 20130101; B32B 5/024 20130101; A43B 17/107 20130101;
A43B 23/02 20130101; A41B 11/005 20130101; B32B 7/12 20130101; B32B
5/026 20130101; B32B 27/322 20130101; A43B 7/125 20130101; A43B
23/042 20130101; B32B 2255/26 20130101; A43B 17/08 20130101; B32B
5/30 20130101; B32B 2307/51 20130101; A43B 23/07 20130101; B32B
2264/0257 20130101; A43B 17/003 20130101; B32B 2307/7265 20130101;
B32B 2437/02 20130101; A43B 23/0235 20130101; A43B 23/026
20130101 |
International
Class: |
A43B 17/10 20060101
A43B017/10; A43B 17/08 20060101 A43B017/08; A43B 17/00 20060101
A43B017/00 |
Claims
1. A bootie comprising: a conformed expanded
polytetrafluoroethylene (ePTFE) membrane containing at least one
integrally joined interface attaching said conformed ePTFE membrane
to itself.
2. The bootie of claim 1, wherein said ePTFE membrane has at least
one additional layer thereon.
3. The bootie of claim 2, wherein said at least one additional
layer is an abrasion resistant coating.
4. The bootie of claim 3, wherein said abrasion resistant coating
is present on at least one of a first side and a second side of
said ePTFE membrane.
5. The bootie of claim 1, wherein said ePTFE membrane has a
thickness variation from a first location in said bootie to a
second location in said bootie of at least 1.2:1.
6. The bootie of claim 1, wherein said integrally joined interface
comprises a patch, stitches, an adhesive, staples, waterproof tape,
or one or more folds.
7. The bootie of claim 1, wherein said bootie further comprises at
least one second component.
8. The bootie of claim 7, wherein said at least one second
component creates regions in said bootie, at least one of said
regions possessing a function or feature different from another
said region.
9. The bootie of claim 7, wherein said at least one second
component is selected from the group consisting of a textile, a
laminate, a textile laminate, a polymer membrane and a second ePTFE
membrane different from said conformed ePTFE membrane.
10. The bootie of claim 1, wherein said conformed ePTFE membrane is
seamless
11. A bootie comprising: a conformed ePTFE membrane containing at
least one integrally joined interface attaching said conformed
ePTFE membrane to itself, said ePTFE membrane having a first side
and a second side; and a textile positioned on said first side of
said ePTFE membrane, wherein said ePTFE membrane and said textile
form a laminate.
12. The bootie of claim 11, wherein said integrally joined
interface comprises a patch, stitches, an adhesive, staples,
waterproof tape, or one or more folds.
13. The bootie of claim 11, wherein said textile is selected from a
knitted textile tube, a woven textile tube, a tubular sock and a
formed sock.
14. The bootie of claim 11, wherein said ePTFE membrane has a
thickness variation from a first location in said bootie to a
second location in said bootie of at least 1.2:1.
15. The bootie of claim 11, wherein at least one of said ePTFE
membrane and said textile has at least one additional layer
thereon.
16. The bootie of claim 15, wherein said one additional layer is an
abrasion resistant coating.
17. The bootie of claim 11, further comprising an adhesive
positioned on at least one of said ePTFE membrane and said
textile.
18. The bootie of claim 17, wherein said adhesive is a
discontinuous adhesive.
19. The bootie of claim 17, wherein said adhesive is a continuous
breathable adhesive.
20. The bootie of claim 11, wherein said cPTFE membrane has a
density greater than or equal to about 2.0 g/m.sup.2.
21. The bootie of claim 11, wherein said bootie has a generally
symmetrical shape.
22. The bootie of claim 11, further comprising at least one second
component attached to said laminate or a portion thereof.
23. The bootie of claim 22, wherein said at least one second
component creates regions in said bootie, at least one of said
regions possessing a function or feature different from another
said region.
24. The bootie of claim 22, wherein said at least one second
component is selected from the group consisting of a textile, a
laminate, a textile laminate, a polymer membrane and a second ePTFE
membrane different from said conformed ePTFE membrane.
25. The bootie of claim 11, wherein said conformed ePTFE membrane
is seamless.
26. A bootie comprising: a conformed expanded
polytetrafluoroethylene (ePTFE) membrane having at least one
integrally joined interface attaching said conformed ePTFE membrane
to itself, said ePTFE membrane having a first side and a second
side; a first textile forming an interior portion of a bootie; and
a second textile forming an exterior portion of said bootie,
wherein said second textile is positioned adjacent said ePTFE
membrane opposing said first textile, and wherein said ePTFE
membrane, said first textile, and said second textile form a
laminate.
27. The bootie of claim 26, wherein said integrally joined
interface comprises a patch, stitches, an adhesive, staples,
waterproof tape, or one or more folds.
28. The bootie of claim 26, wherein said first textile and said
second textile are affixed to said ePTFE membrane with a
discontinuous adhesive.
29. The bootie of claim 26, wherein said first and second textiles
are affixed to said ePTFE membrane with a continuous breathable
adhesive.
30. The bootie of claim 26, wherein at least one of said ePTFE
membrane and said first and second textiles has thereon a
discontinuous adhesive; and wherein at least one of said ePTFE
membrane and said first and second textiles has thereon a
continuous breathable adhesive.
31. The bootie of claim 26, wherein said first textile and said
second textile are selected from a knitted textile tube, a woven
textile tube, a tubular sock and a formed sock.
32. The bootie of claim 26, wherein said ePTFE membrane has a
thickness variation from a first location in said bootie to a
second location in said bootie of at least 1.2:1.
33. The bootie of claim 26, wherein at least one of said ePTFE
membrane, said first textile, and said second textile has at least
one additional layer thereon.
34. The bootie of claim 33, wherein said at least one additional
layer is an abrasion resistant coating.
35. The bootie of claim 26, wherein said ePTFE membrane has a
density greater than or equal to about 2.0 g/m.sup.2.
36. The bootie of claim 26, wherein said bootie has a generally
symmetrical shape.
37. The bootie of claim 26, further comprising at least one
polymeric overlay on said bootie.
38. The bootie of claim 26, further comprising at least one second
component attached to said laminate or a portion thereof.
39. The bootie of claim 38, wherein said at least one second
component creates regions in said bootie, at least one of said
regions possessing a function or feature different from another
said region.
40. The bootie of claim 38, wherein said at least one second
component is selected from the group consisting of a textile, a
laminate, a textile laminate, a polymer membrane and a second ePTFE
membrane different from said conformed ePTFE membrane.
41. The bootie of claim 26, wherein said conformed ePTFE is
seamless.
42. A sock comprising: a conformed expanded polytetrafluoroethylene
(ePTFE) membrane having at least one integrally joined interface
attaching said conformed ePTFE membrane to itself, said ePTFE
membrane having a first side and a second side; and a first elastic
textile affixed to said first side of said ePTFE membrane, said
first elastic textile having an elasticity of at least 50% wherein
said first elastic textile and said ePTFE membrane form a first
laminate.
43. The sock of claim 42, wherein said first textile is selected
from a knitted textile tube, a woven textile tube, and a tubular
sock.
44. The sock of claim 42 wherein said first textile is affixed to
said ePTFE membrane with a discontinuous adhesive.
45. The sock of claim 42, wherein said first textile is affixed to
said ePTFE membrane with a continuous breathable adhesive.
46. The sock of claim 42, wherein said ePTFE membrane has a
thickness variation from a first location in said sock to a second
location in said sock of at least 1.2:1.
47. The sock of claim 42, wherein at least one of said ePTFE
membrane and said first elastic textile has at least one additional
layer thereon.
48. The sock of claim 47, wherein said at least one additional
layer is an abrasion resistant coating.
49. The sock of claim 42, further comprising a second elastic
textile affixed to said second side of said ePTFE membrane, said
second elastic textile having an elasticity of at least 50%,
wherein said ePTFE membrane, said first textile, and said second
textile form a second laminate.
50. The sock of claim 49, wherein said first and second elastic
textiles are selected from a knitted textile tube, a woven textile
tube, a tubular sock and a formed sock.
51. The sock of claim 49, further comprising at least one second
component attached to said second laminate or a portion
thereof.
52. The sock of claim 51, wherein said at least one second
component creates regions in said sock, at least one of said
regions possessing a function or feature different from another
said region.
53. The sock of claim 51, wherein said at least one second
component is selected from the group consisting of a textile, a
laminate, a textile laminate, a polymer membrane and a second ePTFE
membrane different from said conformed ePTFE membrane.
54. The sock of claim 49, wherein said first elastic textile and
said second elastic textile are affixed to said ePTFE membrane with
a discontinuous adhesive.
55. The sock of claim 49, wherein at least one of said ePTFE
membrane and said first and second elastic textile has thereon a
discontinuous adhesive; and wherein at least one of said ePTFE
membrane and said first and second elastic textiles has thereon a
continuous breathable adhesive.
56. The sock of claim 49, wherein said first and second elastic
textiles are affixed to said ePTFE membrane with a continuous
breathable adhesive.
57. The sock of claim 49, further comprising at least one polymeric
overlay on said sock.
58. The sock of claim 49, wherein at least one of said ePTFE
membrane, said first elastic textile, and said second elastic
textile has at least one additional layer thereon.
59. The sock of claim 59, wherein said at least one additional
layer is an abrasion resistant coating.
60. The sock of claim 49, wherein said sock has a generally
symmetrical shape.
61. The sock of claim 49, wherein said ePTFE membrane has a density
greater than or equal to about 2.0 g/m.sup.2.
62. The sock of claim 42, further comprising at least one second
component attached to said first laminate or a portion thereof.
63. The sock of claim 63, wherein said at least one second
component divides said sock into regions, at least one of said
regions possessing a function or feature different from another
said region.
64. The sock of claim 63, wherein said at least one second
component is selected from the group consisting of a textile, a
laminate, a textile laminate, a polymer membrane and a second ePTFE
membrane different from said conformed ePTFE membrane.
65. The sock of claim 63, wherein said conformed ePTFE membrane is
seamless.
66. The sock of claim 42, wherein said conformed ePTFE membrane is
seamless.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to shoe inserts, and
more specifically, to waterproof, breathable booties that are
conformable over a range of shoe sizes. Shoe inserts incorporating
the booties and methods of making the conformable seamless booties
and shoe inserts are provided. Footwear assemblies and waterproof,
breathable socks are also provided.
BACKGROUND OF THE INVENTION
[0002] Waterproof, breathable footwear is typically formed of an
upper material which is both air permeable and water permeable. The
outer layer of the upper material may be leather and/or a textile
fabric. Waterproofness is achieved through the use of a waterproof,
water-vapor permeable functional material that is arranged within
the shoe. In the footwear art, materials which are both waterproof
and water vapor permeable are commonly referred to as "functional"
materials. The functional layer may be made of an expanded
polytetrafluoroethylene (ePTFE) material available from W. L. Gore
and Associates, Inc., Elkton, Md., under the tradename
GORE-TEX.RTM.. The expanded PTFE is characterized as having a
density less than 2.0 g/m.sup.2. Other functional materials have
also been developed and are well known in the art.
[0003] It is difficult to sew the functional layer directly to the
upper and/or sole material of the footwear. In addition, the
functional layer becomes permeable to water when it is pierced
during the sewing process. It is therefore common to provide the
footwear with a shoe insert containing the functional layer. The
shoe insert incorporates several pieces of a laminate that includes
the functional layer and a textile material which are assembled and
joined to produce an insert that includes laminate panels joined by
seams in a manner to have generally the shape of a foot. A
waterproof joining process may be accomplished by sewing the
individual pieces together and sealing the seams with a
superimposed adhesive or sealing tape that is applied to the seam
by a bonding or welding process.
[0004] The shoe insert is generally attached within the footwear
such that the upper end of the shoe insert is connected with the
upper end of the footwear by sewing or by an adhesive. The sole
portion of the shoe insert is held stationary between the outsole
and the insole of the footwear, usually by adhesive bonding over
the entire surface.
[0005] One problem that often results when forming such waterproof,
breathable footwear is that the insertion of the shoe insert often
results in a poor fitting shoe (i.e., the shoe insert has a
different fit (shape or size) to that of the already sized upper)
and/or poor attachment between the shoe insert and the shoe upper
material, which results, among other things, in a less than
desirable appearance of the inside of the footwear (i.e., the shoe
insert appears wrinkled or pulls away from the upper).
[0006] An additional problem is that because of the multiple
laminate pieces or panels needed for manufacturing an article of
waterproof footwear, flexibility may be severely compromised. A
further problem is that sealing the seamed portions of the shoe
insert to make the shoe waterproof may compromise the breathability
and flexibility of the shoe and contribute to the poor fit of the
shoe insert.
[0007] Thus, there remains a need in the art for a shoe insert that
closely conforms to the inside of the shoe, is both waterproof and
breathable, and is comfortable to wear.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a bootie
that contains a laminate including a conformed ePTFE membrane, a
first textile, and, optionally, a second textile. The first textile
may form an interior portion of the bootie and the second textile
may form an exterior portion of the bootie. The textile is not
particularly limited as long as the textile possesses at least some
elastic properties. In at least some exemplary embodiments, the
conformed ePTFE membrane is seamless. In exemplary embodiments, the
first and/or second textile is a sock, which may be tubular in
shape. Additionally, the sock may contain heel and/or toe
reinforcements. The inclusion of heel and toe reinforcements
results in the bootie having a more defined, foot-like shape, which
may be self-supporting. In addition, in exemplary embodiments, the
conformed ePTFE membrane has a thickness variation from a first
location in the bootie to a second location in the bootie of at
least 1.2:1. Also, the bootie is free, or substantially free, of
wrinkles. The bootie has a generally symmetrical shape. In one
embodiment, the ePTFE membrane has a density greater than or equal
to about 2.0 g/m.sup.2, which renders the bootie non-breathable but
provides the wearer protection from an aggressive environment.
[0009] It is also an object of the present invention to provide a
shoe insert that includes a laminate that includes (1) a seamless,
shaped ePTFE membrane and (2) a textile positioned on one side of
the shaped ePTFE membrane. A second textile may be provided on a
second side of the shaped ePTFE membrane opposing the textile. The
textiles may be a knitted textile tube, a woven textile tube, a
tubular sock, or a sock having reinforced heel and/or toe
region(s). In addition, the textile possesses at least some elastic
properties. The ePTFE membrane has a thickness variation from a
first location in the shoe insert to a second location in the shoe
insert of at least 1.2:1. Additionally, the shaped ePTFE membrane
may have thereon a coating, such as an oleophobic coating and/or an
abrasion resistant coating. The shoe insert has generally the shape
of the asymmetrical last.
[0010] It is another object of the present invention to provide a
footwear article that includes a laminate that includes (1) an
upper portion, (2) a shoe insert adjacent to with the upper
portion, and (3) a sole portion adjacent to with the upper portion
and the shoe insert. The shoe insert includes a seamless, shaped
ePTFE membrane, a first textile affixed to one side of the ePTFE
membrane, and optionally, a second textile affixed to a second side
of the ePTFE membrane. The shaped ePTFE membrane may have a
thickness variation from a first location in the shoe insert to a
second location in the shoe insert of at least 1.2:1. The shoe
insert may be affixed to the upper portion and/or sole portion of
the footwear article or, alternatively, the shoe insert may be
removable. There are substantially no air gaps between the upper
portion of the footwear article and the shoe insert. Footwear
articles including the shoe insert do not demonstrate leaking when
filled with water and centrifuged for 30 minutes, thus passing the
Centrifuge Waterproofness Test described herein. A polymeric
overlay may be positioned on the shoe insert to provide additional
cushioning, stability, and/or support. The inclusion of polymeric
overlays may permit the "overlayed" shoe insert to be worn in an
indoor or outdoor environment without being part of a shoe.
[0011] It is yet another object of the present invention to provide
a waterproof sock that includes a laminate that includes (1) a
conformed ePTFE membrane and (2) a first elastic textile affixed to
a first side of the conformed ePTFE membrane. The conformed ePTFE
membrane has membrane a thickness variation from a first location
in the waterproof sock to a second location in the waterproof sock
of at least 1.2:1. A second elastic textile may be affixed to a
second side of the conformed ePTFE membrane. The textile(s)
selection is not particularly limited so long as the textile
possesses at least some elastic properties. In at least one
embodiment, the textile(s) may be a textile tube, a tubular sock,
or a conventional sock with reinforced heel and/or toe regions. The
waterproof sock is formed on a symmetrical last, and as a result,
the waterproof sock has a generally symmetrical shape. The
waterproof sock does not demonstrate leaking when filled with water
and centrifuged for 15 minutes, thus passing the Centrifuge
Waterproofness Test described herein. In one embodiment, the ePTFE
membrane is densified such that the ePTFE membrane has a density
greater than or equal to about 2.0 g/m.sup.2, which renders the
sock non-breathable but provides the wearer protection from an
aggressive environment.
[0012] It is a further object of the present invention to provide a
method of forming a shoe insert that includes (1) applying an
adhesive to a first side of a textile to form a first composite,
(2) positioning the first composite on a symmetrical last with the
adhesive facing outwardly and away from the symmetrical last, (3)
stretching a conformable ePTFE tape having an extensibility of at
least 1.5.times. in at least one direction over the first composite
to form a second composite that includes a conformed ePTFE
membrane, the adhesive, and the textile, (4) heating the second
composite and the symmetrical last to a temperature from about
50.degree. C. to about 200.degree. C. to form a bootie, (5) placing
the bootie on an asymmetrical last, and (6) heating the bootie and
the asymmetrical last to a temperature from about 50.degree. C. to
about 200.degree. C. to form a shoe insert. The shoe insert may be
cooled before removing it from the asymmetrical last. In some
embodiments, the bootie and/or shoe insert may be heated to a
temperature from about 340.degree. C. to about 375.degree. C. to
amorphously lock the ePTFE membrane. The stretching step may
include (1) positioning the conformable ePTFE tape over the
symmetrical last and (2) rotating the symmetrical last through the
conformable ePTFE tape to form the second composite. In the second
heating step, the bootie shrinks to fit the asymmetrical last. In
an alternative embodiment, the bootie may be made to be somewhat
smaller than the asymmetrical last and the bootie is stretched to
fit over the asymmetrical last. In some embodiments, the ePTFE
membrane may have a thickness variation from a first location in
the shoe insert to a second location in the shoe insert of at least
1.2:1.
[0013] It is also an object of the present invention to provide a
method of forming a shoe insert that includes (1) applying a first
adhesive to a first side of a first textile to form a first
composite, (2) positioning the first composite on a symmetrical
last with the first adhesive facing outwardly and away from the
symmetrical last, (3) stretching a conformable ePTFE tape having an
extensibility of at least 1.5.times. in at least one direction over
the first composite to form a second composite comprising a
conformed ePTFE membrane, the first adhesive, and the first
textile, (4) positioning a second textile having thereon a second
adhesive on the second composite such that the second adhesive is
located on the ePTFE membrane to form a third composite, (5)
heating the third composite and the symmetrical last to a
temperature from about 50.degree. C. to about 200.degree. C. to
form a bootie, (6) placing the bootie on an asymmetrical last, and
(7) heating the bootie and the asymmetrical last to a temperature
from about 50.degree. C. to about 200.degree. C. to form a shoe
insert. The shoe insert may be cooled before removing the shoe
insert from the asymmetrical last. In some embodiments, the bootie
and/or shoe insert may be heated to a temperature from about
340.degree. C. to about 375.degree. C. to amorphously lock the
ePTFE membrane. As noted earlier herein, in some embodiments, the
shoe insert may be seamless. The ePTFE membrane may have a
thickness variation from a first location in the shoe insert to a
second location in the shoe insert of at least 1.2:1. The
stretching step may include (1) positioning the ePTFE tape over the
symmetrical last and (2) rotating the symmetrical last through the
ePTFE tape to form the second composite. Alternatively, the bootie
may be made to be somewhat smaller than the asymmetrical last and
the bootie is stretched to fit over the asymmetrical last.
[0014] It is another object of the present invention to provide a
method of forming a bootie that includes (1) applying an adhesive
to a first side of a textile to form a composite, (2) positioning
the composite on a symmetrical last with the adhesive facing
outwardly and away from the symmetrical last, and (3) stretching a
conformable ePTFE tape having an extensibility of at least
1.5.times. in at least one direction over the composite and the
symmetrical last to form a bootie. The bootie is thus formed of a
conformed ePTFE membrane, an adhesive, and a textile. In some
embodiments, the bootie may be heated to a temperature from about
340.degree. C. to about 375.degree. C. to amorphously lock the
ePTFE membrane. The stretching step may include positioning the
ePTFE tape over the symmetrical last and rotating the symmetrical
last through the ePTFE tape. In other embodiments, the bootie is
stretched over the asymmetrical last.
[0015] It is yet another object of the present invention to provide
a method of forming a shoe insert that includes (1) applying an
adhesive on one of a first textile or a side of a conformable ePTFE
tape having an extensibility of at least 1.5.times. in at least one
direction, (2) positioning the textile on a symmetrical last, (3)
stretching the conformable ePTFE tape over the textile to form a
first composite, (4) positioning a second composite including a
second adhesive on a second textile on the first composite such
that the second adhesive is positioned on the ePTFE membrane to
form a bootie, (5) placing the bootie on an asymmetrical last, and
(5) heating the bootie and the asymmetrical last to a temperature
from about 50.degree. C. to about 200.degree. C. to form the shoe
insert. The stretching step may include rotating the symmetrical
last through the ePTFE tape. The placing step may include
stretching the bootie over the asymmetrical last. The first and
second textiles may be a knitted textile tube, a woven textile
tube, a tubular sock, or a formed sock having heel and/or toe
reinforcements. The shoe insert may be self-supporting, such as,
for example when the textile is a formed sock having heel and toe
reinforcements.
[0016] It is also an object of the invention to provide a method of
forming a bootie that includes (1) applying an adhesive on a side
of a first textile or a side of a conformable ePTFE tape having an
extensibility of at least 1.5.times. in at least one direction, (2)
positioning the textile on a symmetrical last, (3) stretching the
conformable ePTFE tape over the textile and symmetrical last to
form a first composite, (4) positioning a second composite
comprising a second adhesive on a second textile on the first
composite such that the second adhesive is positioned on the ePTFE
membrane to form a bootie, and (5) heating the bootie to a
temperature from about 50.degree. C. to about 200.degree. C. In
some embodiments, the bootie is heated to a temperature from about
340.degree. C. to about 375.degree. C. to amorphously lock the
ePTFE membrane. The bootie has a generally symmetrical shape, and
may be breathable over its entirety. In at least one embodiment,
the ePTFE membrane has a density greater than 2.0 g/m.sup.2. The
densified ePTFE provides protection against aggressive
environments.
[0017] It is a further object of the present invention to provide a
bootie that is formed of a conformed ePTFE, membrane and no
textile. The conformed ePTFE membrane may have thereon a coating,
such as an oleophobic coating and/or an abrasion resistant coating.
Additionally, the conformed ePTFE membrane has a thickness
variation from a first location in the bootie to a second location
in the bootie of at least 1.2:1. The bootie, may be formed by
stretching a conformable ePTFE tape over a symmetrical last in a
single step. The bootie has a shape substantially similar to the
symmetrical last. In addition, the bootie may be heated to a
temperature from about 50.degree. C. to about 200.degree. C. to
reduce the ability of the conformed ePTFE membrane to further
stretch and/or to deform. The shoe insert may also, or
alternatively, be heated to a temperature from about 340.degree. C.
to about 375.degree. C. to amorphously lock the conformed ePTFE
membrane. In one embodiment, the conformed ePTFE membrane has a
density greater than or equal to about 2.0 g/m.sup.2, which renders
the bootie non-breathable but provides the wearer protection from
an aggressive environment.
[0018] It is another object of the present invention to provide a
shoe insert that is formed of a shaped ePTFE membrane and no
textile. The shaped ePTFE membrane may have at least one coating
layer thereon, such as, but not limited to, an abrasion resistant
coating and/or an oleophobic coating. In one embodiment, the shaped
ePTFE membrane has an abrasion resistant coating on at least one of
an inner surface of the shoe insert and an outer surface of the
shoe insert. The shoe insert may be formed in a one step process
whereby a conformable ePTFE tape is stretched over an asymmetrical
last. The shoe insert has a shape substantially similar to the
asymmetrical last. The shoe insert may be heated to a temperature
from about 50.degree. C. to about 200.degree. C. to reduce the
ability of the conformed ePTFE membrane to further stretch and/or
to deform. Additionally, the shaped ePTFE membrane may be
amorphously locked. In one embodiment, the ePTFE membrane has a
density greater than or equal to about 2.0 g/m.sup.2, which renders
the shoe insert non-breathable but provides the wearer protection
from an aggressive environment. In a further embodiment, the shoe
insert has a polymeric overlay attached thereto to provide
additional cushioning, stability, and/or support.
[0019] It is a further object of the present invention to provide a
shoe insert formed of a seamless, conformed ePTFE membrane. The
shoe insert may be formed by stretching a conformable ePTFE tape
over a symmetrical last. The shoe insert may be heated to a
temperature from about 340.degree. C. to about 375.degree. C. to
amorphously lock the conformed ePTFE membrane. The conformed ePTFE
membrane has a thickness variation from a first location in the
shoe insert to a second location in the shoe insert of at least
1.2:1. The shoe insert may be breathable over its entirety.
Additionally, the shoe insert may be both waterproof and
breathable. In at least one embodiment, the shoe insert does not
contain a textile and has a shape substantially similar to the
symmetrical last.
[0020] It is yet another object of the present invention to provide
a symmetrical shoe last that contains a first portion and a second
portion where the first and second portions are substantial mirror
images of each other across a generally central axis. The
symmetrical shoe last may be formed to have different shapes and/or
sizes depending on the end use of the article. In addition, the
symmetrical design of the shoe last can be changed to allow for
additional shoe construction features, such as additional tongue
gusset materials, size, width, shoe types, etc, so long as the
symmetry along a centrally located axis remains intact. Thus, the
symmetrical last can be customized to meet a variety of shapes and
sizes to meet desired end uses.
[0021] It a further object of the present invention to provide a
bootie, shoe insert, or waterproof, breathable sock that contains
(1) a laminate of a conformed or shaped ePTFE membrane and at least
one textile and (2) a second component attached to the bootie, shoe
insert, or waterproof, breathable sock, such as with a seam. In
exemplary embodiments, the ePTFE membrane is seamless. The second
component may be, for instance, a textile, a laminate (e.g., a
laminate including a polymer membrane), a textile laminate, a
polymer membrane (e.g. polytetrafluoroethylene or expanded
polytetrafluoroethylene), or a second conformed or shaped ePTFE
membrane different from the first conformed or shaped ePTFE
membrane (e.g., having a characteristic or property different from
the first conformed or shaped ePTFE membrane) in the bootie, shoe
insert, or waterproof, breathable sock. The selection of the second
material is not particularly limited, and may be selected depending
on the desired quality or property desired. It is to be appreciated
that the additional material(s) may be used, for example, to tailor
the bootie, shoe insert, or waterproof, breathable sock to achieve
desired properties and/or a desired appearance.
[0022] It is yet another object of the present invention to provide
a hybrid bootie, shoe insert, or sock where a portion of the
bootie, shoe insert, or sock is removed and the partial bootie,
shoe insert, or sock is attached to a second component. The second
component may be attached to the partial bootie, shoe insert, or
sock by at least one seam. In one embodiment, the bootie, shoe
insert, or waterproof, breathable sock may be cut or otherwise
portioned and that portioned piece of the bootie, shoe insert, or
waterproof, breathable sock may be attached to the second
component.
[0023] It is also an object of the present invention to provide a
bootie, shoe insert, or waterproof, breathable sock that includes a
conformed ePTFE membrane that contains at least one integrally
joined interface, and optionally, at least one textile. In some
embodiments, a second component may be attached to the bootie, shoe
insert, or waterproof sock (or a portion thereof) by any
conventional methods, such as by a seam.
[0024] It is another object of the present invention to provide a
bootie, shoe insert, or waterproof, breathable sock that contains a
laminate of a seamless conformed or shaped ePTFE membrane and at
least one textile where a portion of the laminate is removed and
the partial laminate is affixed to at least one second
component.
[0025] It is an advantage of the present invention that the ePTFE
membrane in the bootie, shoe insert, and waterproof sock may be
seamless.
[0026] It is another advantage of the present invention that shoes
made with shoe inserts having a seamless, shaped ePTFE membrane
have enhanced breathability over shoes made with conventional shoe
inserts made by sewing together pieces of laminate material and
sealing by a bonding or welding process.
[0027] It is yet another advantage of the present invention that
the shoe inserts conform closely to the inside of the shoe, thereby
reducing and even eliminating air gaps between the insert and the
shoe.
[0028] It is a further advantage of the present invention that the
bootie is conformable over a range of shoe sizes and shapes.
[0029] It is also an advantage of the present invention that the
sole portion of the shoe may have breathability.
[0030] It is yet another advantage of the present invention that a
shoe insert having a seamless, shaped ePTFE membrane contains
little or no wrinkles, which increases wear comfort for the
user.
[0031] It is a feature of the present invention that the bootie
conforms in a thermal heating step to shrink to fit a conventional
asymmetrical last over a range of sizes.
[0032] It is yet another feature of the present invention that the
bootie can be stretched to fit a conventional asymmetrical last
over a range of sizes.
[0033] It is also a feature of the present invention that a
polymeric overlay may be positioned on a bootie, shoe insert, or
waterproof, breathable sock to provide additional cushioning,
stability, and/or support.
[0034] It is another feature of the present invention that the
inclusion of polymeric overlays on the shoe insert permits the
"overlayed" shoe insert to be worn in an indoor or outdoor
environment without being part of a shoe.
[0035] It is a further feature of the present invention that the
textile used to form the shoe insert may be a conventional sock, a
knitted textile tube, or a woven textile tube.
[0036] It is yet another feature of the present invention that the
reduction or elimination of air gaps between the insert and the
shoe reduces water pick up.
[0037] It is also a feature of the present invention that the
conformed or shaped ePTFE membrane may be densified such that the
conformed or shaped ePTFE membrane has a density greater than or
equal to about 2.0 g/m.sup.2, which renders the bootie, shoe
insert, or sock non-breathable but provides the wearer protection
from an aggressive environment.
[0038] It is another feature of the present invention that the
seamless booties, shoe inserts, and socks are breathable over their
entireties.
[0039] It is another feature of the present invention that the lack
of seam tape on the shaped ePTFE membrane within the shoe insert
reduces the weight of the insert compared to conventional inserts
or booties made with seam tape.
DEFINITIONS
[0040] The term "conformable ePTFE tape" as used herein is meant to
describe an ePTFE structure that is extendable or extensible in a
first direction, which recovers in a second direction perpendicular
to the first direction, and which is elongated to conform to the
shape of a three dimensional object without fracturing, tearing, or
otherwise breaking.
[0041] The term "extensibility" as used herein is meant to define
the capability of the ePTFE tape to elongate or stretch.
[0042] The term "ePTFE membrane" as used herein with respect the
formation of the booties, shoe inserts and socks described herein,
is meant to describe a conformable ePTFE tape that has been
stretched or expanded over a three dimensional object and which
substantially maintains the three dimensional shape of the object.
It is to be understood that the "ePTFE membranes" described herein
are porous and have a microstructure of nodes interconnected by
fibrils.
[0043] As used herein, the terms "sock", "bootie", and "shoe
insert" are meant to describe footwear articles that encase the
foot of the wearer.
[0044] The term "conformed" as used herein is meant to describe
footwear articles (e.g., sock, bootie, or shoe insert) comprising
an ePTFE membrane, or an ePTFE membrane, having substantially the
shape of a symmetrical or asymmetrical last or a portion
thereof.
[0045] The term "shaped" as used herein is meant to describe
footwear articles (e.g., sock, bootie, or shoe insert) comprising
an ePTFE membrane, or an ePTFE membrane, having substantially the
shape of an asymmetrical last or a portion thereof.
[0046] As used herein, the term "textile" is meant to denote any
woven, nonwoven, felt, knit, stretch spunbond nonwoven, stretch
needlepunched non woven, stretch spunlace non-woven, or fleece and
can be composed of natural and/or synthetic fiber materials and/or
other fibers or flocking materials that has at least some elastic
properties.
[0047] The term "elastic" as used herein is meant to denote that
the material has stretch characteristics and can be tensioned; and,
upon the release of tension, the material returns to its
approximate original dimensions.
[0048] The term "highly elastic" or "high elasticity" as used
herein is meant to describe materials that have stretch
characteristics and can be tensioned at least about 50% (or
greater); and, upon the release of tension, the material returns to
its approximate original dimensions.
[0049] The term "seam" or "seamed" as used herein is meant to
include the joining of two portions, regions, or materials. A seam
may join similar or identical materials or two or more dissimilar
materials (e.g. dissimilar textile pieces or a laminate to a shoe
insert). The terms "seam" and "seamed" are not intended to be
limited to stitching and/or sewing. "Seam" and "seamed" as used
herein are meant to include any suitable means of joining two
portions regions, or materials, such as by adhesives, bonding,
welding, laminating, and the like.
[0050] The term "integrally joined interface" is meant to describe
the joining or attachment of a conformed or shaped ePTFE membrane
to itself (i.e., the same conformed or shaped ePTFE membrane), such
as when the conformed or shaped ePTFE membrane has been folded,
cut, torn, slit, punctured, or otherwise damaged. The joining or
attachment of the conformed or shaped ePTFE membrane to itself may
be accomplished by any suitable means of attachment, such as, for
example, sewing, stitching, gluing, stapling, patching, etc.
[0051] The phrase "waterproof sock" is meant to describe a seamless
waterproof sock made in accordance with the methods described
herein.
[0052] The phrase "hybrid shoe insert" as used herein is meant to
describe a shoe insert that has included therein one or more
region(s) that has a different function(s) or different material(s)
from the shoe insert.
[0053] The phrase "hybrid bootie" as used herein is meant to
describe a bootie that has included therein one or more region(s)
that has a different function(s) or different material(s) from the
bootie.
[0054] The phrase "hybrid sock" as used herein is meant to describe
a sock that has included therein one or more region(s) that has a
different function(s) or different material(s) from the sock.
[0055] The tem "waterproof" as used herein is meant to define a
bootie, shoe insert, shoe, or sock that meets the Waterproof
Centrifuge Tests described herein.
[0056] The term "self-supporting shoe insert" as used herein is
meant to describe a shoe insert that maintains an upright,
substantially vertical orientation with respect to a horizontal
surface without any external support.
[0057] The term "self-supporting bootie" as used herein is meant to
describe a bootie that maintains an upright, substantially vertical
orientation with respect to a horizontal surface without any
external support.
[0058] The term "self-supporting sock" as used herein is meant to
describe a sock that maintains an upright, substantially vertical
orientation with respect to a horizontal surface without any
external support.
[0059] The term "thickness variation" as used herein is meant to
describe a ratio of the difference in thickness of the ePTFE
membrane at a first position compared to a second position.
[0060] The term "amorphously locked" as used herein is meant to
define an ePTFE membrane that has been heated above the crystalline
melt temperature of the PTFE.
[0061] The term "on" as used herein is meant to denote that when an
element is "on" another element, it can be directly on the other
element or intervening elements may also be present.
[0062] The terms "adjacent" and "adjacent to" as used herein are
meant to denote that when an element is "adjacent" to another
element, the element may be directly adjacent to the other element
or intervening elements may be present.
[0063] The term "over" as used herein is meant to denote that when
an element is "over" another element, it can be directly over the
other element or intervening elements may also be present.
[0064] The terms "additional component" or "second component" as
used herein are meant to describe any material, such as a textile,
a laminate (e.g. including a polymer membrane), a textile laminate,
a polymer membrane (e.g., polytetrafluoroethylene or expanded
polytetrafluoroethylene), a second conformed or shaped ePTFE
membrane different from the first conformed or shaped ePTFE
membrane (e.g., having a characteristic or property different from
the first shaped ePTFE membrane), that is attached by at least one
seam to a bootie, shoe insert, or breathable sock described
herein.
BRIEF DESCRIPTIONS OF FIGURES
[0065] The advantages of this invention will be apparent upon
consideration of the following detailed disclosure of the
invention, especially when taken in conjunction with the
accompanying drawings wherein:
[0066] FIG. 1 is a schematic illustration depicting a cross section
of a laminate forming a 2-layer shoe insert in accordance with the
present invention having one textile layer;
[0067] FIG. 2 is a schematic illustration depicting a cross section
of a laminate forming a 3-layer shoe insert according to the
present invention where two textile layers are utilized;
[0068] FIG. 3A is a schematic illustration of a symmetrical last
according to at least one embodiment of the invention;
[0069] FIG. 3B is a schematic illustration of the top view of the
symmetrical last of FIG. 3A showing an axis of symmetry;
[0070] FIG. 4A is a schematic illustration of a conventional
asymmetrical last;
[0071] FIG. 4B is a schematic illustration of the top view of the
asymmetrical last of FIG. 4A showing no axis of symmetry;
[0072] FIG. 5 is a schematic illustration of a three-dimensional
scan of the cross-section of a shoe containing the shoe insert
according to at least one embodiment of the invention taken at a
position 3 cm from the end of the toe area of the shoe;
[0073] FIG. 6 is a schematic illustration of a three dimensional
scan of the cross-section of the shoe depicted in FIG. 5 with an
artificial foot insert positioned therein;
[0074] FIG. 7 is a schematic illustration of a three-dimensional
scan of the cross-section of a shoe containing a conventional shoe
insert taken at a position 3 cm from the end of the toe area of the
shoe;
[0075] FIG. 8 is a schematic illustration of a three-dimensional
scan of the cross-section of the conventional shoe depicted in FIG.
7 containing therein an artificial foot insert;
[0076] FIG. 9 is a schematic illustration of a heel and toe
reinforced shoe insert;
[0077] FIG. 10 is a schematic illustration of a cross-section of a
shoe insert within a shoe comprising an upper and a sole;
[0078] FIG. 11 is a schematic illustration of a hybrid shoe insert
according to one exemplary embodiment of the present invention;
[0079] FIG. 12 is a scanning electron micrograph (SEM) of the
cross-section of the right upper portion of the shoe of Example 5
taken at 300.times. magnification;
[0080] FIG. 13 is a scanning electron micrograph of the
cross-section of toe portion of the shoe of Example 5 taken at
300.times. magnification;
[0081] FIG. 14 is a cross-sectional schematic illustration of a
shoe insert having thereon polymeric overlays;
[0082] FIG. 15 is a cross-sectional schematic illustration of a
partial shoe insert attached to an insole board;
[0083] FIG. 16 is a cross-sectional schematic illustration of a
hybrid shoe insert;
[0084] FIG. 17 is a cross-sectional schematic illustration of a
hybrid shoe insert position in a woman's dress shoe;
[0085] FIG. 18 is a cross-sectional schematic illustration of a
shoe insert having therein a tear in the ePTFE membrane that has
been repaired by stitching the ePTFE membrane together;
[0086] FIG. 19 is a cross-sectional illustration of a hybrid shoe
insert having therein a cut that has been repaired by gluing the
ePTFE membrane; and
[0087] FIG. 20 is a cross-sectional illustration of a shoe insert
where a damaged section of the shoe insert has been repaired by
placing a patch on the shoe insert.
DETAILED DESCRIPTION OF THE INVENTION
[0088] The present invention relates to three dimensional
waterproof, breathable, and conformable booties and shoe inserts
formed from the conformable booties, as well as footwear articles
incorporating the shoe inserts therein. The present invention also
relates to three dimensional waterproof, breathable socks. In
exemplary embodiments, the booties, shoe inserts, and waterproof,
breathable socks include a seamless ePTFE membrane and optionally,
at least one textile. The bootie is conformable over a range of
sizes and shoe shapes (e.g., right and left). For instance, the
bootie may be shaped to fit numerous sizes and shapes (e.g., right
and left) of shoe lasts, thereby eliminating the need to have
multiple sizes of shoe inserts correlating to particular shoe
sizes. The bootie may shrink to fit, or, alternatively, be
stretched to fit, a last having a desired size to form a shoe
insert. The shoe insert reduces or eliminates the need for a
waterproof seam tape, which is conventionally used to make shoe
inserts waterproof. It is to be appreciated that the terms "shoe"
and "boot" as used herein is meant to include men's, women's, and
children's shoes (casual, dress, and running) and boots,
respectively.
[0089] The conformable ePTFE tape used in forming the booties, shoe
inserts, and waterproof socks described herein is capable of
elongating or stretching in a first direction and recovering in a
second direction that is perpendicular to the first direction. The
conformable ePTFE tape has an extensibility in the first direction
from about 1.5.times. to about 140.times.. In some embodiments, the
conformable ePTFE tape has an extensibility in the first direction
greater than about 3.times., greater than about 10.times., greater
than about 30.times., greater than about 40.times., greater than
about 50.times., greater than about 60.times., greater than about
70.times., greater than about 80.times., greater than about
90.times., greater than about 100.times., greater than about
110.times., greater than about 120.times., greater than about
130.times., greater than about 140.times., or even greater. The
extensibility of the conformable ePTFE tape may range from about
3.times. to about 130.times., from about 10.times. to about
120.times., or from about 50.times. to about 100.times.. The
conformable ePTFE tape may or may not be heated prior to elongation
or stretching. Additionally, the conformable ePTFE tape may be
elongated or stretched over a three dimensional object to conform
to the shape of a three dimensional object without fracturing,
tearing, or otherwise breaking.
[0090] One suitable example of a conformable ePTFE tape for use
herein is a conformable expanded polytetrafluoroethylene (ePTFE)
tape, such as an ePTFE tape made in accordance with the teachings
of U.S. Pat. No. 7,306,729 to Bacino, et al, and described in
detail in the Examples set forth below. It is envisioned that other
suitable conformable microporous ePTFE tapes having an
extensibility of at least 1.5.times. in at least one direction may
be utilized in forming the booties, shoe inserts, and waterproof
socks, and would be easily identifiable by those of skill in the
art. The pores of the conformable ePTFE tape may be sufficiently
tight so as to provide waterproofness, yet sufficiently open to
provide properties such as moisture vapor transmission and the
penetration by coatings of colorants and oleophobic or other
compositions. The conformable ePTFE tape may be deformed at room
temperature, or upon the application of heat, into an ePTFE
membrane having a three-dimensional shape. It is to be understood
that the ePTFE membranes described herein are porous and are
characterized by a microstructure of nodes interconnected by
fibrils.
[0091] Expanded polytetrafluoroethylene (ePTFE) is described herein
as an exemplary embodiment, but it is to be appreciated that
expanded PTFE, expanded modified PTFE, and expanded copolymers of
PTFE are all considered to be within the purview of the invention,
and are all considered to be within the meaning of ePTFE as used
herein. Patents have been filed on expandable blends of PTFE,
expandable modified PTFE, and expanded copolymers of PTFE, such as
U.S. Pat. No. 5,708,044 to Branca; U.S. Pat. No. 6,541,589 to
Baillie; U.S. Pat. No. 7,531,611 to Sabol et al.; U.S. patent
application Ser. No. 11/906,877 to Ford; and U.S. patent
application Ser. No. 12/410,050 to Xu et al.
[0092] In addition, the incorporation of filler materials in
various forms within the conformable ePTFE tape and/or ePTFE
membranes is also considered to be within the purview of the
invention. Non-limiting examples of suitable filler materials
include carbon black, aerogels, metals, semi-metals, ceramics,
carbon/metal particulate blends, activated carbon, and the like.
Filler materials may be incorporated into the ePTFE tape and/or
ePTFE membrane by conventional methods, such as those described in
U.S. Pat. No. 4,995,296 to Mortimer, Jr.
[0093] To minimize membrane variability during the formation the
shoe insert, a symmetrical foot last may be utilized. A schematic
illustration of a symmetrical last 80 is depicted in FIGS. 3A and
3B. The last 80 may be formed of virtually any material, such as,
for example, a polymer (e.g., nylon) or a metal (e.g., aluminum
materials). A silicon coating, or other suitable coating, may be
applied to act as a release liner. Unlike conventional lasts, the
symmetrical last 80 has no left or right features or designations.
As shown in FIG. 3B, the symmetrical last 80 is symmetrical along a
centrally located axis represented by reference numeral 105. Thus,
the portions 82 and 84 on either side of the centrally located axis
105 are mirror images, or substantially mirror images of each
other. It is to be appreciated that the symmetrical last 80 may be
formed to have different shapes and/or sizes depending on the end
use of the article. For example, a shoe insert for a running shoe
and a shoe insert for a casual shoe may be made using different
symmetrical lasts due to the different and specific needs of the
two shoe types. Additionally, the symmetrical design of the last
can be changed to allow for additional shoe construction features,
such as, for example, additional tongue gusset materials, size,
width, shoe types, etc, so long as the symmetry along a centrally
located axis remains intact. The symmetrical last 80 can therefore
be customized to meet a variety of shapes and sizes to meet desired
end uses.
[0094] Additionally, the symmetrical last 80 minimizes and even
avoids material stress peaks and subsequent membrane thinning and
fracture during the formation of booties, socks, and shoe inserts
that would result from a traditional asymmetrical foot-shaped last
85, such as is depicted in FIGS. 4A and 4B. Such a foot-shaped last
is conventionally used in shoe construction processes contains
distinctive left and right features and/or left and right foot
designations. A symmetrical shoe insert with no left or right bias,
such as is shown in FIGS. 3A and 3B, produces a suitable precursor
for the subsequent thermal conformation processes taught
herein.
[0095] Turning to FIG. 1, a schematic, cross-sectional view of a
waterproof, breathable laminate 10 having a seamless, conformed
ePTFE layer 20, an adhesive layer 40, and a textile layer 30 can be
seen. The terms "textile(s)" and "textile layer(s)" may be used
interchangeably herein. In forming the laminate 10 of a 2-layer
article, an adhesive 40 may be applied to one side of a textile 30,
and the textile/adhesive composite may be positioned on a
symmetrical last 80 with the adhesive side facing outwardly, i.e.,
away from the last. It is to be noted that positioning the textile
on the symmetrical last 80 prior to applying the adhesive 40 to the
textile 30 is within the scope of the invention. Alternatively, the
adhesive 40 may be positioned on a side of a conformable ePTFE tape
and the ePTFE tape positioned such that the adhesive 40 faces the
textile 30 on the symmetrical last 80.
[0096] The adhesive may be applied discontinuously or continuously,
provided that breathability through the laminate is maintained. For
example, an adhesive may be applied in the form of discontinuous
attachments, such as by discrete dots or in a grid pattern, or in
the form of an adhesive web to adhere the layers of the laminate
together. Alternatively, a breathable adhesive may be applied in a
continuous manner to form a layer of adhesive to adhere the layers
of the laminate together. The adhesive may be a layer of a
thermo-activatable adhesive where activation of the adhesive can be
affected by a heating device. Although the use of adhesives is
described herein with respect to joining (e.g., laminating) the
textile layer to the ePTFE tape, it is to be noted that any
suitable process may be used, such as stitching, sewing, gluing,
ultrasonic bonding, radio frequency welding, flame bonding, heat
sealing gravure lamination, fusion bonding, spray adhesive bonding,
and the like.
[0097] The textile used to form the booties, shoe inserts, and
waterproof socks may be any textile that is air permeable and
breathable and that has at least some elastic properties. Elastic,
as used herein, is meant to denote that the material has stretch
characteristics and can be tensioned; and, upon the release of
tension, the material returns to its approximate original
dimensions. When forming a sock, a textile having a high
elasticity, or an elasticity of at least about 50%, at least about
75%, or at least about 100% or greater. The term "highly elastic"
as used herein is meant to describe materials that have stretch
characteristics and can be tensioned at least about 50% (or
greater); and, upon the release of tension, the material returns to
its approximate original dimensions.
[0098] The textile may be comprised of materials such as, but not
limited, to cotton, rayon, nylon, polyester, silk, lycra, spandex,
elastane, and blends thereof. The weight of the material forming
the textile is not particularly limited except as required by the
application. In some embodiments, the textile may impart sufficient
abrasion resistance to the laminate to provide adequate protection
for the wearer of the article of footwear. Also, the textile may
have a soft hand so that the wearer of the footwear article is
comfortable.
[0099] In exemplary embodiments, the textile is a commercially
available sock or a textile tube (e.g., knitted or woven textile
tube). The sock or textile tube may be formed of virtually any
material or combination of materials as long as the sock or textile
tube is elastic or has at least some elastic characteristics. In
addition, the sock may be tubular or generally tubular in shape, or
may have a formed shape that is generally in the shape of a foot.
Such formed-shape socks may also have reinforced areas, such as in
the toe and/or heel regions. The inclusion of heel and toe
reinforcements results in the bootie and/or shoe insert having a
more defined, foot-like shape. The bootie, shoe insert, and
waterproof, breathable sock, may therefore have an upper portion, a
heel portion, a toe portion, and a sole portion.
[0100] After the adhesive 30 is applied to either the textile 30 or
to the conformable ePTFE tape, or both, the conformable ePTFE tape
is stretched over the symmetrical last 80. In exemplary
embodiments, the symmetrical last 80 is attached to a rotatable arm
and the last 80 is rotated to move the last 80 through the
conformable ePTFE tape, which stretches the conformable ePTFE tape
over the last 80 and into a seamless, conformed ePTFE membrane 20
having the general shape of the symmetrical last 80. The adhesive
may be a continuous breathable adhesive or a discontinuous
adhesive. The ePTFE tape may be held in a fixed orientation
relative to the last 80 prior to moving the symmetrical last 80
through the conformable ePTFE tape. In addition, the conformable
ePTFE tape may be pre-heated prior to conforming the ePTFE tape
over the last 80. It is to be appreciated that other mechanisms may
be used to mechanically "push" or otherwise move the symmetrical
last 80 through the conformable ePTFE tape. Alternatively, the
conformable ePTFE tape may be manually stretched over the
symmetrical last 80. At this stage in the process, the last 80
contains thereon the textile 30, adhesive 40, and the seamless,
conformed ePTFE membrane 20 (i.e., a 2-layer article).
[0101] An abrasion resistant coating may be applied to the ePTFE
membrane 20 to protect the seamless, conformed ePTFE membrane 20
from wear and/or damage. In a 2-layer article, an abrasion
resistant coating may be applied to the ePTFE membrane 20. In use,
the 2-layer article may be positioned such that such that the
coating faces away from the foot (e.g., positioned towards the
shoe) or it may be positioned such that the coating faces the foot
of the wearer (i.e., positioned away from the shoe). An abrasion
resistant coating may also or alternatively be applied to the
surface of the textile. The 2-layer article may be positioned such
that the coating faces either the shoe or the foot. It is to be
appreciated that other coatings (e.g., colorants, oleophobic
coatings, etc.) may be applied in addition to, or in place of, the
abrasion resistant coating. The coating(s) may be applied to all or
part of the surface(s) of the ePTFE membrane or to all or part of
the surface(s) of the textile.
[0102] In forming laminate 70 shown in FIG. 2, a second adhesive 60
is applied to a second textile 50 and the second textile/adhesive
composite is stretched over the symmetrical last 80 with the
adhesive positioned on the exposed surface of the ePTFE membrane.
Thus, the symmetrical last 80 has thereon the first textile 30, the
first adhesive 40, a seamless, conformed ePTFE membrane 20, the
second adhesive 60, and the second textile 50 (i.e., the 3-layer
article). It is to be understood that the textile layer 50 and
adhesive layer 60 may be the same as, or different from, the
textile layer 30 and adhesive layer 40 of laminate 10.
Additionally, it is to be appreciated that laminates 10, 70 may
contain any number of layers as long as the laminate meets the
performance properties described herein.
[0103] In the 3-layer article an abrasion resistant coating may be
applied to all or part of the surface of the first and/or second
textile such that the coating faces the shoe (i.e., positioned away
from the foot). The coating may also or alternatively be applied to
all or part of the surface of the first and/or second textile such
that the abrasion resistant coating faces the foot (i.e., away from
the shoe). Other coatings may be applied in addition to, or in
place of, the abrasion resistant coating.
[0104] The 2-layer article and the 3-layer article may form a
bootie, shoe insert, or a sock, depending, at least in part, on the
textile used to form the article. For example, and as discussed
below, a tubular shaped sock may be used to form a waterproof sock
whereas a reinforced, foot-shaped sock may be used to form a bootie
or shoe insert.
[0105] The 2-layer article and the symmetrical last 80 or the
3-layer article and the symmetrical last 80, depending on the
number of layers desired in the bootie and/or shoe insert, are
heated to a temperature from about 50.degree. C. to about
200.degree. C. or from about 80.degree. C. to about 160.degree. C.,
and generally to about 160.degree. C. (with or without vacuum) in a
conforming step to set the seamless, conformed ePTFE membrane 20
generally into the shape of the symmetrical last 80 and form a
bootie. Accordingly, the bootie may be formed of a conformed ePTFE
membrane and at least one textile. In one embodiment, the ePTFE
membrane is heated above the crystalline melt point of PTFE, for
example to a temperature between about 340.degree. C. and
375.degree. C., to "amorphously lock" the ePTFE and prevent further
changes in shape and/or size of the bootie, reduce the
stretchability of the bootie, and provide stability to the
bootie.
[0106] The temperature in the conforming step is ultimately
dependent upon the adhesive(s) utilized, and should not be so high
as to degrade and/or render useless any portion of the bootie, shoe
insert, or waterproof sock described herein. Additionally, the
conforming step adheres the textile layer(s) to the ePTFE membrane
20, particularly when a vacuum is utilized. The heating may occur
in a conventional oven, an air circulating oven, or the like. It is
to be appreciated that the 2-layer article or 3-layer article may
be heated in the absence of the symmetrical last 80, or partially
heated while positioned on the symmetrical last 80, with the
remainder of the heating occurring in the absence of the
symmetrical last 80 to conform the seamless, conformed ePTFE
membrane 20, so long as the 2-layer article or 3-layer article does
not lose the general shape of the symmetrical last 80.
[0107] Regardless of the number of ePTFE layers 20, textile layers
30, 50, or adhesive layers 40, 60 present in laminates 10, 70, the
number of additional layers added, or the mechanism for bonding the
materials together, the booties described herein will contain
certain properties. For example, a bootie will have a breathability
of at least 3 g/hr, at least 5 g/h, at least 10 g/hr, at least 20
g/hr, or even at least 30 g/hr, or greater. Additionally, the
bootie is advantageously shapeable over a range of shoe sizes and
shapes of lasts (e.g., left or right). Thus, booties according to
the present invention can be manufactured as one size and be shrunk
(or stretched) to fit a variety of shoe sizes, including men's,
women's, and children's sizes.
[0108] After the bootie has been formed, it is removed from the
symmetrical last 80 and loosely placed on a conventional
asymmetrical last 85, which has left and right foot
characteristics. The bootie and asymmetrical last 85 are then
subjected to a shaping step where the bootie and asymmetrical last
85 are heated to a temperature from about 50.degree. C. to about
200.degree. C. for about 5 min to about 30 min. The bootie and the
asymmetrical last 85 may be heated in a conventional oven, an air
circulating oven, or the like. During this thermal dwell, the
bootie "shrinks" and closely shapes to the shape and size of the
conventional asymmetrical last 85, forming a smooth and close
fitting shoe insert to that of the conventional last. In some
embodiments, the ePTFE membrane "amorphously locked" by heating the
ePTFE from about 340.degree. C. and 375.degree. C. to prevent
further changes in shape and/or size of the shoe insert and reduce
the stretchability of the shoe insert. The shoe insert on the
conventional last 85 shows little-to-no wrinkles and has little, if
any, excess material. After the heating is complete, the last 85
and shoe insert are removed from the heat and allowed to cool,
generally to a temperature less than about 50.degree. C. The shoe
insert may then be removed from the last. The shoe insert may also
be permitted to cool prior to removing the shoe insert from the
asymmetrical last 85. The shoe insert is thus formed of a seamless,
shaped ePTFE membrane with at least one textile.
[0109] In an alternate embodiment, the bootie is formed to have a
size somewhat smaller than the size of the asymmetrical last 85,
and is stretched to fit the asymmetrical last 85, with or without
the application of heat, and optionally in a vacuum. It is to be
appreciated that the bootie can be stretched to fit lasts over a
large range of shoe sizes, such as from a woman's sized shoe last
to a men's sized shoe last.
[0110] The booties and shoe inserts may be self-supporting and
maintain the three-dimensional shape of the last even after the
shoe insert is removed from the last. By self-supporting, it is
meant that the bootie or shoe insert (or waterproof, breathable
sock described below) maintains an upright, substantially vertical
orientation without any external support. By substantially vertical
orientation, it is meant to describe a bootie or shoe insert that
has an upright, vertical orientation or a nearly upright, vertical
orientation. This is especially the case when a heel and/or toe
reinforced sock is used to form the bootie and/or shoe insert. A
schematic depiction of a heel and toe reinforced shoe insert is
shown in FIG. 9. As shown, the shoe insert 130 has a toe-reinforced
portion 140 and a heel-reinforced portion 150. The collar 160 and
the upper portion 155 of the shoe insert 130 are also depicted to
achieve a general depiction of the sock as a whole. It is to be
noted that the lines drawn within the shoe insert 130 are to
illustrate the general area that makes up the toe-reinforced
portion 140, the heel-reinforced portion, and the collar 160, and
it not to be construed as a seam of any kind.
[0111] Additionally, the thickness of the conformed or shaped ePTFE
membrane varies within the shoe insert, bootie, and waterproof sock
(discussed below). Using the shoe insert 130 depicted in FIG. 9
merely as an illustrative example, the thickness of the shaped
ePTFE membrane measured at the heel portion 150 may be different
than the thickness measured at the toe portion 140 of the shoe
insert 130. Similarly, the thickness of the shaped ePTFE membrane
at the heel portion 150 may be different than the thickness
measured at the upper portion 155 of the shoe insert 130.
[0112] The ratio of the thickness variation of the conformed or
shaped ePTFE membrane within the shoe insert, bootie, or waterproof
sock ranges from 1.2:1 to 5:1, from 1.25:1 to 5:1, from 1.3:1 to
5:1, from 1.5:1 to 5:1, from 2:1 to 5:1, from 2:1 to 4:1, or from
2:1 to 3.1, depending upon the locations selected within the shoe
insert, bootie, or waterproof sock. In exemplary embodiments, the
thickness variation of the conformed or shaped ePTFE membrane from
a first location to a second location in the shoe insert, bootie,
or waterproof sock is at least 1.2:1, at least 1.25:1, at least
1.5:1, at least 2:1, at least 2.1:1, at least 2.5:1, at least 3:1,
at least 4:1, or at least 5:1 or even greater. The thickness is
measured from one side of the ePTFE membrane to the other side of
the ePTFE membrane. It is notable that the side portions and tongue
portion of the shoe insert tend to have a thicker ePTFE membrane
compared to other parts of the shoe insert, even though the side
portions and tongue portion of the shoe insert receive the most
stretching over the symmetrical last.
[0113] The shoe insert may be used in the formation of footwear
articles, such as shoes and boots. A shoe or boot containing the
shoe insert may be formed in any manner known to those of skill in
the art. It is to be noted that all standard and/or conventional
methods of making and/or assembling footwear articles as known by
those of skill in the art may be utilized, and are considered to be
within the scope of the invention. For instance, molding pressing,
gluing, stitching, fusion welding, fusion bonding, compression
molding, upper bonding, ultrasonic welding, a well as any
conventional or commercial tooling are considered to be within the
purview of the invention.
[0114] In one embodiment, natural or synthetic upper materials may
be stitched together to form a shoe upper. Toe and heel protectors
may then be attached to the shoe upper. A shoe insert may then be
attached to the shoe upper by stitching and/or adhering the shoe
insert to the collar portion of the upper of the shoe. The
synthetic upper materials and stitched/adhered shoe insert may then
be then repositioned onto a conventional asymmetric last where a
rubber adhesive is placed on the heel, toe, and sole areas. Any
suitable adhesive, such as a solvent based chloroprene rubber
adhesive, may be used as the adhesive. It is to be appreciated that
a shoe may be made by placing the shoe insert into a shoe without
any adhesive so that the shoe insert may be easily removed from the
shoe if needed.
[0115] A protective layer, such as an ethylene vinyl acetate (EVA)
layer, may be adhered to an additional component (e.g., an insole
board) with the previously applied rubber adhesive. The protective
layer may also, or alternatively, be attached to the sole of the
shoe insert. The shoe upper may then be lasted around the shoe
insert and attached additional component to form a close fitting
shoe insert with the synthetic upper materials. Thus, the shoe
insert fits very closely to the contour of the outer portions of
the shoe. Finally, a sole (synthetic material, rubber, or other
natural material) may be attached to the insole of the shoe insert
using another adhesive, such as a solvent based polyurethane
adhesive, to complete the waterproof, breathable shoe construction.
Shoes made with the shoe insert are highly breathable, and may have
a breathability of at least 3 g/hr, or at least 5 g/hr or at least
10 g/hr, or at least 15 g/hr, or at least 20 g/hr, or even at least
30 g/hr, or greater. In one exemplary embodiment, the shoe or boot
is made entirely formed of breathable component, thus making the
shoe or boot breathable over its entirety. For example, a footwear
article formed of an upper portion, a shoe insert, and a sole
portion, each of the upper portion, shoe insert, and sole may be
breathable.
[0116] In another exemplary embodiment, the conformable ePTFE tape
may be used to form a waterproof, breathable sock. In particular, a
2-layer or 3-layer article may be made as described in detail above
with the exception that the symmetrical last is typically smaller
in size than the size of the symmetrical last used to make the
bootie and shoe insert described above. The smaller symmetrical
last allows the waterproof, breathable sock to maintain at least
some elastic characteristics. In exemplary embodiments, the sock(s)
utilized to form the waterproof, breathable sock are tubular socks
or knitted or woven textile tubes that do not contain toe and heel
reinforcements and contain some fibers with high elasticity.
Generally, the sock or textile tube used to form the waterproof
sock has a higher elasticity than the socks and textile tubes used
to form the bootie and/or shoe insert, and may be "highly elastic"
and have an elasticity of at least about 50%. It is to be
appreciated that socks containing heel and/or toe reinforcements
may be utilized to form a waterproof, breathable sock as long as
the sock is highly elastic.
[0117] The waterproof, breathable sock does not undergo a shaping
step on an asymmetrical last; however, it is to be appreciated that
the waterproof, breathable sock could undergo a shaping step in
which the sock is conformed with the application of heat (e.g., in
a conventional oven) onto a conventional asymmetrical last to form
a shoe insert. The waterproof, breathable socks have a generally
symmetrical shape due, at least in part, to the elastic nature of
the textile used (e.g. highly elastic sock or highly elastic
textile tube). The waterproof, breathable socks have a
breathability of at least 3 g/hr, or at least 5 g/hr or at least 10
g/hr, or at least 15 g/hr, at least 20 g/h, or even at least 30
g/hr, or greater.
[0118] In some embodiments, the bootie, shoe insert, or waterproof,
or breathable sock may have thereon a polymeric overlay. The
overlay(s) may be attached to the bootie, shoe insert, or
waterproof, breathable sock by any suitable means such as, but not
limited to, adhering, bonding, or stitching the overlay to the
bootie or shoe insert. The application of a polymeric overlay (e.g.
a thermoplastic or a thermoset material) may provide additional
cushioning and/or support to the bootie, shoe insert, or
waterproof, breathable sock. A shoe insert 190 with polymeric
overlays 180, 185 is depicted schematically in FIG. 14. The
polymeric overlays 180 provide both stability and support to the
shoe insert 190. Polymeric overlay 185, which is positioned at the
sole of the shoe insert 190, also provides protection to the
wearer's foot (indicated by dashed line 195) and a gripping surface
for the shoe insert 190. Polymeric overlays 180, 185 may be joined
to the shoe (or bootie or waterproof, breathable sock) by any
suitable attachment mechanisms, such as, but not limited to a seam
200. The inclusion of polymeric overlays may permit the "overlayed"
shoe insert to be worn in an indoor or outdoor environment, without
being part of a shoe. Similarly, the presence of a polymeric
overlay(s) on a bootie or waterproof, breathable sock provides
additional support and/or protection to the bootie or sock and may
permit the bootie or sock to be worn in an indoor or outdoor
environment without any other laminates or textiles attached
thereto or without the bootie being inserted into a shoe.
[0119] It is to be appreciated that in an alternative embodiment,
laminates 10, 70 may be pre-formed and subsequently and
sequentially formed over symmetrical last 80 and asymmetrical last
85 and heated as discussed above to form the bootie and/or the shoe
insert, and/or the waterproof, breathable sock.
[0120] In a separate embodiment, one or more laminate containing
the seamless, shaped ePTFE membrane, such as, for example, laminate
10 or laminate 70, may be used to form a shoe insert. For example,
appropriately sized and shaped laminate pieces may be joined at
seamed portions to form a shoe inert. The seamed portions may then
be rendered waterproof, such as by superimposing a waterproof
sealant (e.g., a waterproof adhesive) or by applying a waterproof
tape through a bonding or welding process. As one non-limiting
example of forming a shoe insert, laminate 10 or 70 may be cut into
appropriately sized and shaped pieces and joined to form an upper
portion and a sole portion of a shoe insert. The upper portion and
the sole portion may be joined in any conventional manner, such as
by sewing, welding, or bonding the pieces together. The seams may
then be rendered waterproof such as by applying the waterproof
adhesive or tape discussed above. Prior to applying any waterproof
adhesive or tape, the seamed, laminate shoe insert may be heated in
a manner described above in a shaping step to conform to an
asymmetrical last 85.
[0121] In another embodiment, the conformable ePTFE tape may be
stretched over a conventional asymmetric last and formed into a
shoe insert in a single step. The shoe insert (either with or
without the asymmetrical last) may be heated to a temperature from
about 50.degree. C. to about 200.degree. C. to reduce the ability
of the ePTFE membrane to further stretch and/or to deform. The shoe
insert may also be heated to a temperature from about 340.degree.
C. to about 375.degree. C. to amorphously lock the conformed ePTFE
membrane. The shoe insert of this embodiment is formed of a
seamless, conformed ePTFE membrane that has a shape substantially
similar to the asymmetric last. In addition, the shoe insert may
have one or more polymeric overlay thereon.
[0122] In yet another embodiment, a shoe insert having a generally
symmetrical shape and which does not contain a textile is formed in
a one step process. In this embodiment, the conformable ePTFE tape
is stretched over a symmetrical last to form the shoe insert. The
shoe insert (either with or without the symmetrical last) may be
heated to a temperature from about 50.degree. C. to about
200.degree. C. to reduce the ability of the ePTFE membrane to
further stretch and/or to deform. The shoe insert may additionally,
or alternatively, be heated to a temperature from about 340.degree.
C. to about 375.degree. C. to amorphously lock the conformed ePTFE
membrane. The shoe insert of this embodiment is a seamless,
conformed shoe insert having generally the shape of the symmetrical
last. The shoe insert may have one or more polymeric overlay
thereon.
[0123] In a further embodiment, the conformable ePTFE tape may be
stretched over a conventional asymmetric last and made into a shoe
insert in two steps (e.g. a conforming and a shaping step). In this
particular embodiment, the shoe insert does not contain any
textile. For instance, the conformable ePTFE tape may be stretched
over a symmetrical last and heated to a temperature (e.g., from
about 50.degree. C. to about 200.degree. C.) in a conforming step
to create a seamless, conformed ePTFE membrane having a shape that
is generally the shape of the symmetrical last and form a bootie.
The bootie may then be positioned over an asymmetrical last and
heated (e.g. 50.degree. C. to about 200.degree. C.) in a shaping
step to shrink the ePTFE membrane to fit the asymmetrical last and
form a shoe insert. The seamless, shaped ePTFE membrane may be
"amorphously locked" by heating the shaped ePTFE membrane to a
temperature between about 340.degree. C. and 375.degree. C. to
prevent further changes in shape and/or size of the shoe insert and
reduce the stretchability of the shoe insert. The seamless, shaped
ePTFE membrane may have a coating thereon, such as, for example, to
render the membrane hydrophobic, oleophobic, dimensionally stable,
and/or abrasion resistant. Thus, a shoe insert may be made entirely
of a seamless, shaped ePTFE membrane. In addition, the shoe insert
may have one or more polymeric overlay thereon.
[0124] Similarly, a waterproof, breathable sock made entirely of a
seamless, conformed ePTFE membrane may be formed by not subjecting
the seamless conformed ePTFE membrane to the shaping step. Such a
waterproof, breathable sock has a shape substantially similar to
the symmetric last.
[0125] In a further embodiment, the conformable ePTFE tape may be
stretched over a symmetric last and formed into a bootie in a
single step. The bootie (either with or without the symmetrical
last) may be heated to a temperature from about 50.degree. C. to
about 200.degree. C. to reduce the ability of the ePTFE membrane to
further stretch and/or to deform or to a temperature from about
340.degree. C. to about 375.degree. C. to amorphously lock the
conformed ePTFE membrane. The bootie is thus formed of a seamless,
conformed ePTFE membrane that has a shape substantially similar to
the symmetric last. The bootie may have thereon one or more
polymeric overlay.
[0126] In another embodiment, a bootie or shoe insert may be formed
by positioning a textile/adhesive composite on a symmetrical or an
asymmetrical last as described in detail above. Next, a laminate
including an ePTFE tape, a second adhesive, and a second textile
may be formed. The bootie or shoe insert may be formed by
stretching the laminate over the textile/adhesive composite.
Additional heating steps as described herein may be conducted to
finish forming the bootie or shoe insert.
[0127] The booties, shoe inserts, and waterproof, breathable socks
described above have continuous, seamless layer(s) of ePTFE. In
other words, each conformed or shaped ePTFE membrane in the bootie,
shoe insert, or shoe insert is formed of a single conformed or
shaped ePTFE membrane. As such, there are no seams in the conformed
or shaped PTFE membrane within the booties, shoe inserts, and
waterproof, breathable socks. Shoes formed with the shoe inserts
are therefore more comfortable to wear, particularly when compared
to conventional shoe inserts formed with seamed portions where
laminate pieces are attached to each other. As discussed herein,
the shoe inserts having therein seamless shaped ePTFE membranes do
not form or contain, or only minimally form or contain, folds,
wrinkles, or seams that would ultimately compromise the
breathability and/or fit of the shoe insert in the shoe.
[0128] Additionally, booties, shoe inserts, and waterproof,
breathable socks having a seamless conformed or shaped ePTFE
membrane described herein are highly breathable over the entirety
of the bootie, shoe insert, or waterproof, breathable sock, which
is at least partially due to the breathable laminate forming the
bootie, shoe insert, or waterproof, breathable sock and the lack of
seams in the conformed or shaped ePTFE membrane. For example, for a
shoe insert having an upper portion, a heel portion, a toe portion,
and a sole portion, each of these portions may be breathable.
Further, shoe inserts with a seamless, shaped ePTFE membrane
demonstrate improved breathability over conventional shoe inserts
that are formed of multiple pieces of laminate sewn together, and
often sealed with a waterproof tape such as GORE-SEAM.RTM. tape
(available from W. L. Gore and Associates, Inc.), which is not
breathable. A cross sectional schematic view depicting the shoe
insert 95 positioned within a shoe containing a shoe upper 90 and a
sole 120 is depicted in FIG. 10. It is to be noted that a shoe
insert with a seamless shaped ePTFE membrane closely follow the
contours of the shoe, leaving little to no space or air gaps
between the shoe insert and the shoe.
[0129] A second component may be attached to the bootie, shoe
insert, or waterproof, breathable sock to form a hybrid bootie,
hybrid shoe insert, or hybrid sock. The second component may
provide a different function or feature and/or it may be formed of
a different material from the bootie, shoe insert, or waterproof,
breathable sock. The additional component may be, for instance, a
textile, a laminate (e.g., a laminate including a polymer
membrane), a textile laminate, a polymer membrane, or a second
conformed or shaped ePTFE membrane different from the first
conformed or shaped ePTFE membrane (e.g., having a characteristic
or property different from the first conformed or shaped ePTFE
membrane) in the bootie, shoe insert, or waterproof, breathable
sock. The selection of the second component is not particularly
limited, and may be chosen depending on the desired quality or
property. It is to be appreciated that the second component(s) may
be used, for example, to tailor the bootie, shoe insert, or
waterproof, breathable sock to achieve desired properties and/or a
desired appearance. The second component may be attached to the
bootie, shoe insert, or waterproof, breathable sock by any
conventional joining or attaching method. Non-limiting examples of
such methods include stitching, sewing, gluing, ultrasonic bonding,
radio frequency welding, flame bonding, and heat sealing
lamination, fusion bonding, spray adhesive bonding, and the like.
Further, it is to be noted that the terms "second component" and
"second material" may be used interchangeably herein.
[0130] One example of a hybrid shoe insert 250 is depicted in FIG.
16. The depicted hybrid shoe insert 250 includes a shoe insert 220
attached to a second component 230 (e.g., a textile, a laminate, a
textile laminate, a polymer membrane, or a second shaped ePTFE
membrane) by a seam 240, although, as discussed above, any method
for joining the shoe insert 250 to the second component 230 may be
utilized. The hybrid shoe insert 250 illustrated in FIG. 16 may be
used in the formation of a boot, or in a situation where a portion
located above the shoe insert 220 needs (or is desired) to have a
functionality or feature that is different from what is provided by
the shoe insert 220. It is to be appreciated that any number of
portions or seams within the hybrid shoe insert as well as any
number of positions for the seams, is considered to be within the
purview of the invention.
[0131] One embodiment containing various portions or regions within
a shoe insert is depicted in FIG. 11. The conformed/shaped ePTFE
and textile(s) forming the shoe insert may be cut and portion(s)
removed therefrom. The portion(s) removed may then be replaced by
one or more second component. In another embodiment, the portion
that is removed may be attached to at least one second component.
The second materials may possess differing characteristics, such
as, for example, different breathability and/or different
waterproofness and/or different aesthetic appearances. In one or
more embodiment, seams may be rendered waterproof by sealing the
seams with a waterproof tape (e.g., GORE-SEAM.RTM. tape (available
from W. L. Gore and Associates, Inc.). It is to be appreciated that
the bootie containing one or more seams in FIG. 11 is merely
illustrative, and one or more seam may be utilized in the socks and
booties described herein in a similar manner.
[0132] In FIG. 11, the shoe insert contains two seams 175, which
creates three separate "zones" or "regions" (illustrated as 1, 2,
and 3, respectively) within the shoe insert. For example, zone 1
may contain the portioned shoe insert, and zones 2 and 3 may each
contain a second component. Alternatively, zone 2 shown in FIG. 11
may contain the portioned shoe insert and zones 1 and 3 may each
contain a second material. It is to be appreciated that any
combination of shoe insert portion(s) and second component(s) are
within the purview of the invention. It is also to be understood
that any number of zones (and seams) may be present in a hybrid
bootie, hybrid shoe insert, or hybrid waterproof, breathable sock,
and that such embodiments are considered to be within the purview
of the invention. Additionally, the joining mechanisms (e.g.,
stitching or gluing) may be positioned in locations where the
joining mechanism is not likely to interfere with the comfort of
the person donning the bootie, shoe insert, or sock.
[0133] In another embodiment, portions of the shoe inserts descried
herein may be used in shoe construction. For instance, the sole
(bottom portion) of a shoe insert may be removed and the partial
shoe insert (e.g. upper portion of the shoe insert) may be attached
to an additional component (e.g. insole board), such as is depicted
schematically in FIG. 15. Specifically, FIG. 15 depicts a partial
shoe insert 210 (with the sole removed) adhered to an insole board
215 via an adhesive 225. It is to be appreciated that any suitable
process for joining the partial shoe insert to the additional
component may be used, such as stitching, sewing, gluing,
ultrasonic bonding, radio frequency welding, flame bonding, and
heat sealing gravure lamination, fusion bonding, spray adhesive
bonding, injection molding, and the like. It is to be understood
that any portion or part of the bootie or shoe insert may be
removed and that such partial booties and partial shoe inserts are
considered to be within the scope of the invention.
[0134] A hybrid shoe insert may be utilized in both men's and
women's shoes. One example of a hybrid shoe insert utilized within
a woman's shoe is schematically depicted in FIG. 17. In this
embodiment, the hybrid shoe insert contains a shoe insert portion
305 and a second component portion 310. Both the shoe insert
portion 305 and the second component portion 310 are located within
a shoe 300, as depicted by the dashed lines. In this example, the
component portion 310 may be formed of a textile, for example, for
ease comfort when wearing the shoe 300. Similar to the shoe inserts
described above, hybrid shoe inserts fit very closely to the
contour of the outer portion 315 of the shoe 300.
[0135] It is to be appreciated that although seams are referenced
herein with respect to hybrid shoe inserts any of the booties, shoe
inserts, or waterproof, breathable socks described herein may
contain at least one seam as described above. Any number of seams,
as well as any number of regions formed by the seams, are
considered within the scope of the invention.
[0136] In some instances, the conformed or shaped ePTFE membrane
may be cut, slit, torn, punctured, or otherwise damaged, either
during the manufacturing of the bootie, shoe insert, or waterproof,
breathable sock or after the bootie, shoe insert, or sock has been
made. In a situation where the conformed or shaped ePTFE becomes
discontinuous (such as where the conformed or shaped ePTFE membrane
is damaged or torn), the conformed or shaped ePTFE membrane may be
joined (e.g., repaired) by attaching the conformed or shaped ePTFE
membrane to itself at an integrally joined interface. In one
exemplary embodiment shown in FIG. 18, a shoe insert 300 containing
a shaped ePTFE membrane having a cut or tear therein may be joined
(e.g., stitched) together at an integrally joined interface 310. In
another exemplary embodiment depicted in FIG. 19, a tear may be
present in the shaped ePTFE membrane in a hybrid shoe insert 320
containing a shoe insert portion 220 and a second component 230
joined at seam 240. The shaped ePTFE may be joined to itself at an
integrally joined interface 225 by an adhesive 235. In a further
embodiment, the ePTFE may be folded at an integrally formed
interface for aesthetic reasons, such as to form a pleat or
tuck.
[0137] In a further embodiment, a tear or other damage in a
conformed or shaped ePTFE membrane may be repaired by utilizing a
patch, such as is shown in FIG. 20. In FIG. 20, damage to the
shaped ePTFE membrane in the shoe insert 330 has been repaired by
positioning a patch 340 over the damaged area. The patch may be
adhered, stitched, or otherwise affixed to the shoe insert 330. It
is to be appreciated that a shoe inserts containing a damaged
shaped ePTFE membrane are merely illustrative, and one or more
integrally joined interface may be utilized in the booties and
socks described herein in a similar manner.
[0138] In yet another embodiment, an elastic or at least partially
elastic tubular textile may be utilized to form a sock by applying
an adhesive to the tubular textile and positioning the tubular
textile/adhesive composite on a symmetrical last with the adhesive
positioned outwardly, away from the symmetrical last. The
symmetrical last may then be pushed through the conformable ePTFE
tape to position the conformable ePTFE membrane on the tubular
textile. The tubular textile with the ePTFE membrane thereon may be
seamed at the toe portion to form a sock.
[0139] In a further embodiment, the ePTFE membrane may be densified
by any conventional method such that the ePTFE membrane has a
density of 2.0 g/m.sup.2 or greater. Booties, shoe inserts, and
socks may be formed with such densified ePTFE membranes; however,
the booties, shoe inserts, and socks made from the densified ePTFE
membranes would not be breathable. The densified ePTFE membrane
provides protection against aggressive environments, such as, but
not limited to, exposure to hazardous chemicals or biological
threats.
Test Methods
[0140] It should be understood that although certain methods and
equipment are described below, any method or equipment determined
suitable by one of ordinary skill in the art may be alternatively
utilized.
Conformability Assessments
[0141] To assess the conformability of the shoe insert in the
formed shoe, the surface of the inner shoe can be felt by hand to
determine any folds, wrinkles or seams that would ultimately
compromise comfort fit. In addition, the shoes can be scanned using
a scanning device to visually determine the presence or absence of
air gaps to indicate how closely the shoe insert fits to the upper
shoe materials.
Whole Boot Moisture Vapor Transmission Rate Test
[0142] The Whole Boot Moisture Vapor Transmission Rate for each
sample was determined in accordance with the Department of Defense
Army Combat Boot Temperate Weather Specifications. The
specifications are as follows:
[0143] Whole Boot Breathability
[0144] The boot breathability test shall be designed to indicate
the Moisture Vapor Transmission Rate (MVTR) through the test sample
by means of a difference in concentration of moisture vapor between
the interior and the exterior environment.
[0145] Apparatus
[0146] a. The external test environment control system shall be
capable of maintaining 23 (.+-.1).degree. C. and 50%.+-.2% relative
humidity throughout the test duration.
[0147] b. The weight scale shall be capable of determining the
weight of test samples filled with water to an accuracy of
(.+-.0.01) gram.
[0148] c. The water holding bag shall be flexible so that it can be
inserted into the test sample and conform to the interior contours;
it must be thin enough so that folds do not create air gaps; it
must have much higher MVTR than the footwear product to be tested;
and it must be waterproof so that only moisture vapor contacts the
interior of the footwear product rather than liquid water.
[0149] d. The internal heater for the test sample shall be capable
of controlling the temperature of the liquid water uniformly in the
test sample to 35 (+1.degree. C.
[0150] e. The sealing method around the collar of the test sample
shall be impervious to both liquid water and water vapor.
[0151] Procedure
[0152] a. Place sample in test environment and condition for at
least 12 hours.
[0153] b. The heating device is inserted into the water holding bag
and the complete assembly is then placed into the test sample
opening and filled with water to a height of 5 cm measured from
inside sole.
[0154] c. Seal opening around the collar with plastic wrap around
the top of the footwear and tape over using packaging tape.
[0155] d. Heat water in test sample to 35.degree. C.
[0156] e. Weigh test sample and record as Wi.
[0157] f. Hold temperature in test sample after weighing for a
minimum of 4 hours.
[0158] g. After a minimum of 4 hours, reweigh test sample. Record
weight as Wf and test duration as Td.
[0159] h. Calculate MVTR of the test sample in grams/hour from the
equation below: MVTR=(Wi-Wf)/Td
Shoe and Shoe Insert Centrifuge Waterproofness Tests
[0160] (1) Waterproofness for each shoe sample was determined by
use of the Centrifuge test described in U.S. Pat. No. 5,329,807 to
Sugar, et al. assigned to W.L. Gore and Associates, Inc. and
incorporated by reference herein in its entirety. The centrifuge
tests were carried out for 30 minutes. The shoe sample was
considered to be waterproof if no leakage was seen after 30
minutes
[0161] (2) Waterproofness for the 2-layer bootie samples and shoe
insert samples (bootie after thermally conforming to a 265 sized
running shoe last) was determined by a modified Centrifuge test
described in U.S. Pat. No. 5,329,807 to Sugar, et al. assigned to
W.L. Gore and Associates, Inc. To ensure accurate waterproof
testing of socks, 800 mls of water was added to each sample which
was then secured on a fixture using hose clamps around the rim of
the upper heel area of the sock. The centrifuge tests were carried
out for 60 minutes. The sample was considered to be waterproof if
no leakage was seen after 60 minutes.
Sock Moisture Vapor Transmission Rate Test
[0162] The Moisture Vapor Transmission Rate for each sock was
determined in accordance with Department of Defense Army Combat
Boot Temperate Weather Specification with the exception that a sock
was used as the test sample. The specifications were as
follows:
[0163] The sock breathability test shall be designed to indicate
the Moisture Vapor Transmission Rate (MVTR) through the sock by
means of a difference in concentration of moisture vapor between
the interior of the sock and the exterior environment of the
sock.
[0164] Apparatus.
[0165] a. The external test environment control system shall be
capable of maintaining 23 (.+-.1.degree. C. and 50%+2% relative
humidity throughout the test duration.
[0166] b. The weight scale shall be capable of determining the
weight of test samples filled with water to an accuracy of (+0.01)
gram.
[0167] c. The water holding bag shall be flexible so that it can be
inserted into the test sample and conform to the interior contours;
it must be thin enough so that folds do not create air gaps; it
must have much higher MVTR than the footwear product to be tested;
and it must be waterproof so that only moisture vapor contacts the
interior of the footwear product rather than liquid water.
[0168] d. The internal heater for the test sample shall be capable
of controlling the temperature of the liquid water uniformly in the
test sample to 35 (+1.degree. C.
[0169] e. The sealing method around the collar of the test sample
shall be impervious to both liquid water and water vapor.
[0170] Procedure.
[0171] a. Place sample in test environment and condition for at
least 12 hours.
[0172] b. The heating device is inserted into the water holding bag
and the complete assembly is then placed into the test sample
opening and filled with water to a height of 5 cm measured from
inside sole.
[0173] c. Seal opening around the collar with plastic wrap around
the top of the footwear and tape over using packaging tape.
[0174] d. Heat water in test sample to 35.degree. C.
[0175] e. Weigh test sample and record as Wi.
[0176] f. Hold temperature in test sample after weighing for a
minimum of 4 hours.
[0177] g. After a minimum of 4 hours, reweigh test sample. Record
weight as Wf and test duration as Td.
[0178] h. Calculate MVTR of the test sample in grams/hour from the
equation below: MVTR=(Wi-Wf)/Td
[0179] As a further modification and to represent the sock moisture
vapor transmission rate when the sock is worn in a shoe, the
moisture vapor transmission rate tests were repeated with the socks
placed in a large size running shoe taking care to minimize air
gaps. The same running shoe was used in each test and was dried
using a hot air drier between tests. Throughout the tests, the
total weight of the sock and shoe was measured to determine water
vapor transmission rates.
[0180] A running shoe was made with synthetic upper materials (part
number DMT20130502, commercially available from Dong Min Textile,
3173-24, Mungji-Dong, Gangseo-Ku, Busan, Korea). The synthetic
upper materials of the shoe were stitched together to form the
upper of the shoe. Toe and heel protectors were then attached to
the upper of the shoe. A 6 oz canvas toe puff (commercially
available from Dae Kyung Tex Co. #C-135 Gamjeon-dong Sasang-Gu,
Busan, Korea) and a Rhenoflex 3105 heel counter having a thickness
of 1.6 mm (commercially available from Rhenoflex, Giulinistrasse 2
67065 Ludwigshafen, Germany) were obtained and attached to the
upper of the shoe. No liner materials were added.
[0181] The upper materials were then repositioned onto a large
sized running shoe last and a solvent based chloroprene rubber
adhesive was placed on the heel and toe areas (8250 supplied by
Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku,
Busan, Korea) and sole (8700H supplied by Henkel Technologies
Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) area. A
protective EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M.
Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to
a non woven insole board (1.4 mm supplied by Han Young Industry
Co., Ltd, #394-5 Samrak-dong Sang-Gu, Busan, Korea) using a solvent
based chloroprene rubber adhesive (8700H supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea). The upper materials were then lasted around the attached
insole board, as known in the art to form a close fitting liner
with the upper materials. Finally, a rubber sole was attached to
the insole board using a solvent based polyurethane adhesive
(6190S, part number ZY30204093) available from Henkel Technologies
Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea to
complete the shoe construction.
Sock Centrifuge Waterproofness Test
[0182] Waterproofness for each sock test sample was determined by
use of the Centrifuge test described in U.S. Pat. No. 5,329,807 to
Sugar, et al. assigned to W.L. Gore and Associates, Inc. To ensure
accurate waterproof testing of socks, 700 mls of water was added to
each sock test sample which was then secured on a fixture using
hose clamps around the rim of the upper heel area of the sock. The
centrifuge tests were carried out for 60 minutes. The sock test
sample was considered to be waterproof if no leakage was seen after
60 minutes.
Expanded PTFE Tape Characterization
[0183] The expanded PTFE tape utilized in the Examples set forth
herein was tested according to the ASTM 638 Plastic Tensile
Strength Test. Three (3) samples were taken from the PTFE tape in
both longitudinal (machine) and transverse directions. Average
values for the three samples were calculated.
[0184] The longitudinal samples had a thickness of 0.28 mm, a mass
of 226 g/m.sup.2, a bulk density of 0.80 g/cc, a maximum load of
8.68 kgf and an extensibility (strain at max load) of a strain at
max load of 34%. The transverse samples had a thickness of 0.28 mm,
a mass of 220 g/m.sup.2, a bulk density of 0.77 g/cc, a maximum
load of 0.11 kgf and an extensibility (strain at max load) of
8422%.
EXAMPLES
Example 1
[0185] A symmetrical cast aluminum foot last having a shape as
depicted generally in FIG. 3 was fixed onto a clamp which can
rotated through an angle of approximately 140.degree. using a
pneumatic cylinder. A polyurethane adhesive web (UT8, 20 g/m.sup.2
polyurethane non-woven hot melt adhesive commercially available
from Protechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was
applied to one side of a commercially available 30 denier (33 dtex)
100% Polyamid black sock (Knie 30 Leicht deckend obtained from the
Nur Die GmbH, Rheine, Germany) using a heat press set at
130.degree. C. and effective pressure of 5 psi. The sock with the
polyurethane adhesive web thereon was positioned tightly over the
last. The sock was applied to the last with the adhesive web
exposed on the outer surface of the last. Care was taken when
applying the sock to the last to avoid wrinkles.
[0186] A fine powder of PTFE polymer (Daiken Industries, Ltd.,
Orangeburg, N.Y.) was blended with Isopar.RTM. K (Exxon Mobil
Corp., Fairfax, Va.) in the proportion of 0.196 g/g of fine powder.
The lubricated powder was compressed in a cylinder to form a pellet
and placed into an oven set at 70.degree. C. for approximately 12
hours. Compressed and heated pellets were ram extruded to produce
tapes approximately 15.2 cm wide by 0.73 mm thick. Three separate
rolls of tape were produced and layered together between
compression rolls to a thickness of 0.76 cm. The tape was then
transversely stretched to 56 cm (i.e., at a ratio of 3.7:1),
restrained, and then dried in an oven set at 270.degree. C. The dry
tape was longitudinally expanded between banks of rolls over a
heated plate set to a temperature of 340.degree. C. The speed ratio
between the second bank of rolls and the first bank of rolls, and
hence the expansion ratio, was 8:1.
[0187] A portion of the expanded PTFE tape having a length of
approximately 1 meter and a width of approximately 12.5 cm was
fixed in a frame by placing the edges of the PTFE tape between two
securing metal plates. The tape was further secured by compressing
the PTFE tape between the plates using 5 screw bolts positioned
along the tape length. To ensure that the width of the PTFE tape
remained fixed, each tape edge and plate assembly was secured to
the frame using locking nuts. The secured PTFE tape in the frame
had a width of 9 cm.
[0188] The complete frame containing the PTFE tape and securing
plates were then placed under an IR heater set at 100% (full power)
for 10 seconds during which the tape reached a temperature of
40-50.degree. C. The locking nuts were then released and the edges
of the tape were slowly, manually moved apart until the tape was
expanded in the width direction to a width of 27 cm. To prevent
shrink back of the PTFE tape and to maintain the 27 cm tape width,
the frame edges were again secured using the locking nuts. After
the PTFE tape was expanded in the width direction and secured using
the locking nuts, the tape was heated under the IR heater, which
was set at 100% (full power) for 30 seconds, during which the tape
reached a temperature of 70-80.degree. C.
[0189] The frame containing the expanded PTFE tape was then quickly
removed from under the heater and positioned above the symmetrical
last. The pneumatic cylinder was then activated to allow the
symmetrical last having thereon the sock and adhesive to rotate
upwardly at an angle of 90.degree. to penetrate and deform the
preheated PTFE tape around the last. The final deformation of the
tape to conform the tape to the general shape of the last was
completed by hand to ensure that the tape was deformed closely to
the shape of the last and to minimize wrinkles.
[0190] A second commercially available 30 denier (33 dtex) 100%
Polyamid black sock (Knie 30 Leicht deckend commercially available
from Nur Die GmbH, Rheine, Germany) having thereon a polyurethane
adhesive web (UT8, 20 g/m.sup.2 polyurethane non-woven hot melt
adhesive commercially available from Protechnic, 41 Avenue
Montaigne, F-68700, Cernay, France) was then placed over the
deformed PTFE tape with the polyurethane adhesive positioned in
direct contact with the surface of the deformed expanded PTFE tape.
Care was taken to minimize wrinkling of the PTFE tape and the
sock.
[0191] The resulting 3-layer article (i.e., sock/deformed, expanded
PTFE tape/sock) was then secured at the collar of the last using an
elastomeric retaining band to prevent further movement. The
complete assembly containing the 3-layer article and the
symmetrical aluminum last was then placed in an oven set at
160.degree. C. for a time of 45 min. During this thermal dwell
time, the assembly reached an approximate temperature of
130.degree. C. The assembly was then removed and a silicon vacuum
bag was quickly applied over the assembly. A vacuum was applied at
20-25 inches Hg for 10 min to ensure good contact between the three
separate layers and to allow for subsequent adhesive bonding
between the socks and the expanded PTFE tape.
[0192] Cool, compressed air was then passed through the assembly
for an additional 10-20 min while under vacuum to cool the assembly
to approximately 50.degree. C. The vacuum and compressed air were
removed from the assembly. Next, the silicon bag was removed. The
elastomeric retaining band was removed from the last. Finally, the
completed 3-layer bootie was slowly and carefully removed from the
last.
Example 2
[0193] A symmetrical nylon foot last having a shape as depicted
generally in FIG. 3 was fixed onto a clamp which can be rotated
through an angle of approximately 140.degree. using a pneumatic
cylinder. A polyurethane adhesive web (UT8, 20 g/m.sup.2
polyurethane non-woven hot melt adhesive obtained from Protechnic,
41 Avenue Montaigne, F-68700, Cernay, France) was applied to one
side of a commercially available 60 den (66 dtex) 61% polyamide,
37% cotton, and 2% elastane black sock (Sockchen Naturelle 60
obtained from the Nur Die GmbH, Rheine, Germany) using a heat press
set at 130.degree. C. and an effective pressure of 5 psi. The sock
with the polyurethane adhesive web thereon was positioned tightly
over the last. The sock was applied to the last with the adhesive
web exposed on the outer surface of the last. Care was taken when
applying the sock to the last to avoid wrinkles.
[0194] A portion of the expanded PTFE tape produced in Example 1
having a length of approximately 1 meter and a width of
approximately 7.4 cm was obtained and fixed in a frame by placing
the edges of the PTFE tape between six toggle clamps positioned
along the tape edges and compressing between two rubber seals. To
ensure that the width remained fixed, each tape edge and clamp
assembly was fixed to the frame using locking nuts. The secured
tape in the frame had a width of 6.9 cm.
[0195] The tape fixed in the frame was then heated using an
industrial air heater for approximately 20 seconds, during which
the PTFE tape reached a temperature of 40-50.degree. C. The locking
nuts were then released and the edges of the tape were slowly,
manually moved apart until the tape was expanded in the width
direction to a width of 37.1 cm. To prevent shrink back of the PTFE
tape and to maintain the tape width, the frame edges were again
secured using the locking nuts. After the PTFE tape was expanded in
the width direction and secured using the locking nuts, the tape
was then heated using the industrial air heater, during which the
tape reached a temperature of approximately 70.degree. C.
[0196] The frame containing the expanded PTFE tape was removed from
the heat and positioned above the symmetrical last. The pneumatic
cylinder was then activated to allow the symmetrical last having
thereon the sock and adhesive to rotate in an upward direction at
an angle of 90.degree. to penetrate and deform the preheated PTFE
tape around the last. The final deformation of the tape to conform
the tape to the general shape of the last was completed by hand to
ensure that the tape deformed closely to the shape of the last and
to minimize wrinkles.
[0197] The 2-layer article (i.e., sock/deformed expanded PTFE tape)
was then secured at the collar of the last using an elastomeric
retaining band to prevent further movement. The complete assembly
containing the 2-layer article and nylon last was then placed in an
oven set at 140.degree. C. for a time of 30 min. During this dwell
time, the assembly reached an approximate temperature of
120.degree. C. The assembly was then removed and a vacuum bag was
quickly applied over the assembly. A vacuum was applied at 27
inches Hg until the assembly had cooled to approximately 50.degree.
C. to ensure good contact between the two layers (i.e., sock and
polyurethane adhesive) and to allow for subsequent adhesive bonding
between the sock and the expanded PTFE tape layer. The vacuum was
then removed from the assembly. Next, the vacuum bag and the
elastomeric retaining band were removed from the last. The
completed 2-layer bootie was slowly and carefully removed from the
last.
[0198] The 2-layer bootie was then tested for water vapor
permeability (breathability) using the Whole Boot Moisture Vapor
Transmission Rate test method outlined above with the expanded PTFE
membrane layer positioned on the exterior part of the test sample.
The average water vapor permeability was determined to be 27.3
g/hr.
[0199] In addition, the 2-layer bootie was tested for
waterproofness according to the Modified Centrifuge Test for
waterproofness described above. The shoe insert met the
waterproofness standard, showing no water leaks after 60 min.
Example 3
[0200] A 2-layer bootie was produced in the same manner as Example
2. A 2-layer shoe insert was then thermally shaped by loosely
placing the bootie onto a conventional men's 265 running shoe last
with the expanded PTFE membrane layer exposed on the upper surface
and heating the precursor in an air circulating oven at 140.degree.
C. for 30 min. During this thermal dwell, the shoe insert closely
conformed to the shape and size of the conventional, asymmetrical
last, thereby forming a smooth and close fitting shoe insert to the
last. The last was removed from the oven and allowed to cool to
less than 50.degree. C., after which the two-layer shoe insert was
removed from the conventional, asymmetric last.
[0201] The three-dimensional shoe insert was then tested for water
vapor permeability (breathability) using the Whole Boot Moisture
Vapor Transmission Rate test method outlined above with the
expanded PTFE membrane layer exposed on the upper surface. The
average water vapor permeability was determined at 31.8 g/hr.
[0202] The three-dimensional shoe insert was also tested for
waterproofness according to the Modified Centrifuge Test for
Waterproofness described above. The 2-layer bootie met the
waterproofness standard, showing no water leaks after 60 min.
Example 4
[0203] A waterproof running shoe was made with synthetic upper
materials suitable for a running shoe (part number DMT20130502
commercially available from Dong Min Textile, 3173-24, Mungji-Dong,
Gangseo-Ku, Busan, Korea). The synthetic upper materials of the
shoe were stitched together to form the upper of the shoe. Toe and
heel protectors were then attached to the upper of the shoe. A 6 oz
canvas toe puff (commercially available from Dae Kyung Tex Co.
#C-135 Gamjeon-dong Sasang-Gu, Busan, Korea) and a Rhenoflex 3105
heel counter having a thickness of 1.6 mm (commercially available
from Rhenoflex, Giulinistrasse 2 67065 Ludwigshafen, Germany) were
obtained and attached to the upper of the shoe.
[0204] A 3-layer bootie was produced in the same manner as Example
1. A 3-layer bootie was thermally shaped by loosely placing the
bootie onto a conventional men's 280 size running shoe asymmetrical
last and heating the bootie and last in an air circulating oven at
140.degree. C. for 30 min. During this thermal dwell, the bootie
closely conformed to the shape and size of the conventional,
asymmetrical last, thereby forming a smooth and close fitting shoe
insert to the last. The last was then removed from the oven and
allowed to cool to less than 50.degree. C., after which the shoe
insert was removed from the conventional, asymmetric last.
[0205] During shoe production, the conformed shoe insert was again
placed on the 280 size running shoe last to form a smooth and close
fit around the last with no seams, noticeable wrinkles, or excess
material. The shoe insert was then cut and trimmed around the heel
collar area to ensure the shoe insert pattern was correctly
sized.
[0206] The shoe insert was removed from the last and attached to
the synthetic upper materials by stitching the shoe insert to the
collar portion of the upper of the shoe. The synthetic upper
materials and stitched shoe insert were then repositioned onto the
280 size running shoe last and a solvent based chloroprene rubber
adhesive was placed on the heel and toe areas (part number 8250
commercially available from Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area (8700H
supplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,
Saha-Ku, Busan, Korea).
[0207] A protective ethylene vinyl acetate (EVA) layer (2.0 mm,
hardness 55 commercially available from Dong Bo S.M. Co., Ltd
#520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to a
non-woven insole board (1.4 mm supplied by Han Young Industry Co.,
Ltd, #394-5 Samrak-dong Sang-Gu, Busan, Korea) using the solvent
based chloroprene rubber adhesive (8700H commercially available
from Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,
Saha-Ku, Busan, Korea). The EVA protective layer was then attached
to the sole of the shoe insert. The synthetic upper materials were
then lasted around the shoe insert and attached insole board to
form a close fitting shoe insert with the synthetic upper
materials. Finally, a rubber sole was attached to the insole of the
shoe insert using a solvent based polyurethane adhesive (6190S,
part number ZY30204093, commercially available from Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) to complete the shoe construction.
[0208] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Moisture Vapor Transmission
Rate test method outlined above in the whole boot moisture vapor
transmission rate test. The average water vapor permeability was
determined at 11.9 g/hr.
[0209] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected shoes met the waterproofness standard, showing
no water leaks after 30 min.
[0210] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of fit of the shoe insert shows
that no folds, wrinkles, or seams were present to compromise the
comfort fit characteristics of the shoes.
Comparative Example 1
[0211] A waterproof shoe was made with synthetic upper materials
suitable for a running shoe (commercially available from Dong Min
Textile, 3173-24, Mungji-Dong, Gangseo-Ku, Busan, Korea, part
number DMT20130502). The synthetic upper materials were stitched
together to form the upper of the waterproof shoe. A toe protector
and heel protector were then attached to the upper. A 6oz canvas
toe puff (supplied by Dae Kyung Tex Co. #C-135 Gamjeon-dong
Sasang-Gu, Busan, Korea) and a Rhenoflex 3105 heel counter having a
thickness of 1.6 mm (commercially available from Rhenoflex,
Giulinistrasse 2 67065 Ludwigshafen, Germany) were obtained and
attached to the upper of the shoe.
[0212] A shoe insert made of a laminate of expanded
polytetrafluoroethylene and a textile (part number VISI001001B,
commercially available from W.L. Gore and Associates Inc., Elkton,
Md.) was formed. The laminate was cut and stitched together to form
a shoe insert of the correct size and shape of a 280 size running
shoe last. GORE-SEAM.RTM. tape (commercially available from W.L.
Gore and Associates Inc., Elkton, Md.) was then applied to the
stitched seams of the shoe insert to form a waterproof seam. The
shoe insert was then positioned on the 280 size running shoe last
which formed a reasonable fit around the last, although wrinkles
and excess material were noted.
[0213] The shoe insert was then removed from the last and attached
to the synthetic upper materials of the running shoe by stitching
the shoe insert to the collar portion of the upper. The synthetic
upper materials and stitched shoe insert were then repositioned
onto the 280 size running shoe last and a solvent based chloroprene
rubber adhesive was placed on the heel and toe areas (8250 supplied
by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku,
Busan, Korea) and sole area (8700H supplied by Henkel Technologies
Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). A
protective EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M.
Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to
the non woven insole board (1.4 mm supplied by Han Young Industry
Co., Ltd, #394-5 Samrak-dong Sang-Gu, Busan, Korea) using a solvent
based chloroprene rubber adhesive (8700H supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) and the EVA protective layer was then attached to the sole
of the shoe insert. The upper materials were then lasted around the
shoe insert and attached insole board to form a close fitting shoe
insert with the upper materials. Finally, a rubber sole was
attached to the insole of the liner using a solvent based
polyurethane adhesive (6190S, part number ZY30204093, commercially
available from Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoe
construction.
[0214] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined at
8.8 g/hr.
[0215] The selected shoes were then tested for waterproofness
utilizing the Centrifuge Test for Waterproofness described above
showing no water leaks after 30 min. The selected footwear met the
waterproofness standard.
[0216] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of the fit of the shoe insert
showed that significant folds, wrinkles, and seams were present,
especially in the toe areas which would be expected to compromise
comfort fit characteristics of the shoes.
Example 5
[0217] A waterproof running shoe was made with synthetic upper
materials suitable for a running shoe (part number DMT20130502,
commercially available from Dong Min Textile, 3173-24, Mungji-Dong,
Gangseo-Ku, Busan, Korea). The upper materials were stitched
together to form the upper of the waterproof footwear. A 6 oz
canvas toe puff (supplied by Dae Kyung Tex Co. #C-135 Gamjeon-dong
Sasang-Gu, Busan, Korea) and a Rhenoflex 3105 heel counter having a
1.6 mm thickness (commercially available from Rhenoflex,
Giulinistrasse 2 67065 Ludwigshafen, Germany) were attached to the
upper of the shoe.
[0218] A 3-layer bootie was produced in the same manner as Example
1. The 3-layer bootie was then thermally conformed by loosely
placing the bootie onto a conventional ladies 230 size running shoe
asymmetrical last and heating the bootie and last in an air
circulating oven at 140.degree. C. for 30 min. During this thermal
dwell, the bootie closely conformed to the shape and size of the
conventional, asymmetrical last, thereby forming a smooth and close
fitting shoe insert to the last. The last was removed from the oven
and allowed to cool to less than 50.degree. C., after which the
shoe insert was removed from the conventional, asymmetric last.
[0219] During shoe production, the conformed shoe insert was again
placed on the 230 size running shoe last to form a smooth and close
fit around the last with no seams, noticeable wrinkles, or excess
material. The shoe insert was then cut and trimmed around the heel
collar area to ensure the shoe insert pattern was correctly sized.
The shoe insert was removed from the last and attached to the
synthetic upper materials by stitching the shoe insert to the
collar portion of the upper materials.
[0220] The upper materials and stitched shoe insert were then
repositioned onto the 230 size shoe last and a solvent based
chloroprene rubber adhesive was placed on the heel and toe areas
(8250 supplied by Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area (8700H
supplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,
Saha-Ku, Busan, Korea). A protective EVA layer (2.0 mm, hardness 55
supplied by Dong Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu,
Busan, Korea) was adhered to the non woven insole board (1.4 mm,
supplied by Han Young Industry Co., Ltd, #394-5 Samrak-dong
Sang-Gu, Busan, Korea) using a solvent based chloroprene rubber
adhesive (8700H supplied by Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA protective layer
was then attached to the sole of the shoe insert. The upper
materials were then lasted around the shoe insert and attached
insole board to form a close fitting shoe insert with the upper
materials. Finally, a rubber sole was attached to the insole of the
shoe insert using a solvent based polyurethane adhesive (6190S,
part number ZY30204093, commercially available from Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea to complete the shoe construction.
[0221] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 11.0 g/hr.
[0222] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard,
showing no water leaks after 30 min.
[0223] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of the fit of the shoe insert shows
that no folds, wrinkles, or seams were present to compromise
comfort fit characteristics of the shoes.
[0224] Three thickness measurements of the ePTFE membrane from the
right side upper portion of the shoe and of the ePTFE membrane from
the toe portion were measured and recorded. Average measurements
were as follows: right side upper portion=44.87 microns and toe
portion=23.27 microns. The thickness ratio was determined to be
approximately 2:1. SEMs taken at 300.times. magnification of the
right side upper portion and toe portion are shown in FIGS. 12 and
13, respectively. The ePTFE membrane is identified as reference
numeral 170.
Comparative Example 2
[0225] A waterproof running shoe was made with synthetic upper
materials suitable for a running shoe (part number DMT20130502,
commercially available from Dong Min Textile, 3173-24, Mungji-Dong,
Gangseo-Ku, Busan, Korea). The synthetic upper materials were
stitched together to form the upper of the waterproof shoe. A 6oz
canvas toe puff (supplied by Dae Kyung Tex Co. #C-135 Gamjeon-dong
Sasang-Gu, Busan, Korea) and a Rhenoflex 3105 heel counter having a
thickness of 1.6 mm (supplied by Rhenoflex, Giulinistrasse 2 67065
Ludwigshafen, Germany) were attached to the upper of the shoe.
[0226] A shoe insert made of a laminate of expanded
polytetrafluoroethylene and a textile (part number VISI001001B,
commercially available from W.L. Gore and Associates, Inc., Elkton,
Md.) was formed. The laminate was cut and stitched together to form
a shoe insert having the size and shape of the 230 running shoe
last. GORE-SEAM.RTM. tape (available from W.L. Gore and Associates
Inc., Elkton, Md.) was then applied to the stitched seams to form a
waterproof seam over the stitched seams of the shoe insert. The
shoe insert was then placed on the 230 size shoe last which formed
a reasonable fit around the last, although wrinkles and excess
material were noted.
[0227] The shoe insert was then removed from the last and attached
to the synthetic upper materials of the running shoe by stitching
the liner to the collar portion of the upper. The synthetic upper
materials and stitched liner were then repositioned onto the 230
size shoe last and a solvent based chloroprene rubber adhesive was
placed on the heel and toe areas (8250 supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) and sole area (8700H supplied by Henkel Technologies Korea,
604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).
[0228] A protective EVA layer (2.0 mm, hardness 55 supplied by Dong
Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was
adhered to the non woven insole board (1.4 mm supplied by Han Young
Industry Co., Ltd, #394-5 Samrak-dong Sang-Gu, Busan, Korea) using
the solvent based chloroprene rubber adhesive (8700H supplied by
Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku,
Busan, Korea). The EVA protective layer was then attached to the
sole of the shoe insert. The upper materials were then lasted
around the liner and attached insole board to form a close fitting
shoe insert with the upper materials. Finally, a rubber sole was
attached to the insole of the shoe insert using a solvent based
polyurethane adhesive (6190S, part number ZY30204093, commercially
available from Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoe
construction.
[0229] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 6.4 g/hr.
[0230] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard,
showing no water leaks after 30 min.
[0231] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of shoe insert fit shows that
significant folds, wrinkles, and seams were present, especially in
the toe areas that would be expected to compromise comfort fit
characteristics of the shoes.
Example 6
[0232] A waterproof casual shoe was made with natural split suede
leather upper materials suitable for a casual shoe (part number
JS120130501, commercially available from J. S. IND Co., Ltd.
#1086-9, Janglim-Dong, Saha-Ku, Busan, Korea). The suede leather
upper materials were stitched together to form the upper of the
waterproof shoe. A 0.6 mm toe puff (part number TFL060,
commercially available from Han Young Industry Co., Ltd, #394-5
Samrak-dong Sasang-Gu, Busan, Korea) and a 1.7 mm heel counter
leather board (supplied by Young Poly Chemical Co. Ltd. #907-7
Manduck 3-dong Buk-Gu, Busan, Korea) were attached to the upper of
the shoe.
[0233] A 3-layer bootie was produced in the same manner as Example
1. The S-layer bootie was then thermally conformed by loosely
placing the bootie onto a conventional men's 280 size casual shoe
asymmetrical last and heating the bootie and last in an air
circulating oven at 140.degree. C. for 30 min. During this thermal
dwell, the bootie closely conformed to the shape and size of the
conventional, asymmetrical last, thereby forming a smooth and close
fitting shoe insert to the last. The last was removed from the oven
and allowed to cool to less than 50.degree. C., after which the
shoe insert was removed from the conventional, asymmetric last.
[0234] During shoe production, the conformed shoe insert was again
placed on the men's 280 size casual shoe last to form a smooth and
close fit around the last with no seams, noticeable wrinkles, or
excess material. The shoe insert was then cut and trimmed around
the heel collar area to ensure the shoe insert pattern was
correctly sized. The shoe insert was then removed from the last and
attached to the leather upper materials of the casual shoe by
stitching the shoe insert to the collar portion of the upper.
[0235] The suede leather upper materials and stitched liner were
then repositioned onto the 280 size casual shoe last and a solvent
based chloroprene rubber adhesive was placed on the heel and toe
areas (8250 supplied by Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole areas (8700H
supplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,
Saha-Ku, Busan, Korea). A protective EVA layer (2.0 mm, hardness
55, supplied by Dong Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu,
Busan, Korea) was adhered to the insole board (A TEX 6331+Blue Tex
commercially available from Dong Bo S.M. Co., Ltd #520-36
Gouebob-dong Sang-Gu, Busan, Korea) using a solvent based
chloroprene rubber adhesive (8700H supplied by Henkel Technologies
Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA
protective layer was then attached to the sole of the shoe insert.
The upper materials were then lasted around the liner and attached
insole board. Finally, a rubber sole was attached to the insole of
the shoe insert using a solvent based polyurethane adhesive (6190S,
part number ZY30204093, commercially available from Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) to complete the shoe construction.
[0236] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 6.8 g/hr.
[0237] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard,
showing no water leaks after 30 min.
[0238] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of fit of the shoe insert revealed
that no folds, wrinkles or seams were present to compromise comfort
fit characteristics of the shoes. Utilizing 3D scanning equipment,
images of the shoe cross section at various positions along the
shoe length were captured. FIG. 5 represents a typical
cross-sectional image at a position 3 cm from the end of the shoe
toe area. The 3-layer shoe insert 95 showed a very close fit to the
upper leather materials 90 with no evidence of folds, seams, and
minimal air spaces.
[0239] In order to better illustrate the fit of the shoe insert in
the shoe during use, additional 3D scans were taken with an
artificial foot insert of the appropriate size. A schematic
illustration of such a scan of a cross-section of a shoe with an
artificial foot positioned therein is depicted in FIG. 6. As shown
in FIG. 6, there is minimal contact between the shoe insert 95 and
the foot insert 100. Such minimal contact indicated excellent
comfort and excellent fit for the wearer of the shoe.
Comparative Example 3
[0240] A waterproof casual shoe was made with natural split suede
leather upper materials suitable for a casual shoe (part number
JS120130501 commercially available from J. S. IND Co., Ltd.
#1086-9, Janglim-Dong, Saha-Ku, Busan, Korea). The upper materials
were stitched together to form the upper of the waterproof casual
shoe. A 0.6 mm toe puff (part number TFL060, commercially available
from Han Young Industry Co., Ltd, #394-5 Samrak-dong Sasang-Gu,
Busan, Korea) and a 1.7 mm leather board heel counter (supplied by
Young Poly Chemical Co. Ltd. #907-7 Manduck 3-dong Buk-Gu, Busan,
Korea) were attached to the upper of the shoe. A shoe insert were
made of a laminate of expanded polytetrafluoroethylene and a
textile (part number VISI001001B, commercially available from W.L.
Gore and Associates Inc., Elkton, Md.). The laminate was cut and
stitched together to form a shoe insert having the size and shape
of a 280 size casual shoe last. GORE-SEAM.RTM. tape (commercially
available from W.L. Gore and Associates Inc., Elkton, Md.) was then
applied to the stitched seams to form a waterproof seam over the
stitched seams of the shoe insert. The shoe insert was then placed
on the 280 size shoe last which formed a reasonable fit around the
last, although wrinkles and excess material were observed.
[0241] The shoe insert was then removed from the last and attached
to the leather upper materials of the casual shoe by stitching the
shoe insert to the collar portion of the upper. The upper materials
and stitched liner were then repositioned onto the 280 size casual
shoe last and a solvent based chloroprene rubber adhesive was
placed on the heel and toe areas (8250 supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) and sole area (8700H supplied by Henkel Technologies Korea,
604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).
[0242] A protective EVA layer (2.0 mm, hardness 55 supplied by Dong
Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was
adhered to the insole board (A TEX 6331+Blue Tex supplied by Dong
Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) using
a solvent based chloroprene rubber adhesive (8700H supplied by
Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku,
Busan, Korea). The EVA protective layer was then attached to the
sole of the shoe insert. The upper materials were then lasted
around the shoe insert and attached insole board. Finally, a rubber
sole was attached to the insole of the liner using a solvent based
polyurethane adhesive (6190S, part number ZY30204093, commercially
available from Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoe
construction.
[0243] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 6.5 g/hr.
[0244] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard,
showing no water leaks after 30 min.
[0245] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of the fit of the shoe insert
showed that significant folds, wrinkles, or seams were present,
especially in the toe areas, which would be expected to compromise
comfort fit characteristics of the shoes. Utilizing 3D scanning
equipment, images of the shoe cross section at various positions
along the shoe length were captured. FIG. 7 depicts a schematic
illustration of a typical cross-sectional image at a position 3 cm
from the end of the shoe toe area. As shown in FIG. 7, the
polytetrafluoroethylene-based shoe insert 110 showed a relatively
poor fit to the upper leather materials 90 with evidence of
significant folds and large air spaces 120 between the shoe insert
110 and upper materials 90.
[0246] To better illustrate the fit during use, additional 3D scans
were taken with an artificial foot insert 100 of the appropriate
size. A schematic depiction of a typical scan of a cross-section of
the shoe with the artificial shoe insert 100 is depicted in FIG. 8,
clearly highlighting a significant number of contacts or
interactions between the shoe insert 110 and foot insert 100, which
would be expected to compromise comfort fit.
Example 7
[0247] A waterproof woman's casual shoe was made with natural split
suede leather upper materials suitable for a casual shoe (part
number JS120130501, commercially available from J. S. IND Co., Ltd.
#1086-9, Janglim-Dong, Saha-Ku, Busan, Korea). The upper materials
were stitched together to form the upper of the waterproof casual
shoe. A 0.6 mm toe puff (part number TFL060, commercially available
from Han Young Industry Co., Ltd, #394-5 Samrak-dong Sasang-Gu,
Busan, Korea) and a 1.7 mm leather board heel counter (supplied by
Young Poly Chemical Co. Ltd. #907-7 Manduck 3-dong Buk-Gu, Busan,
Korea. Liner materials) were attached to the upper of the shoe.
[0248] A 3-layer bootie was produced in the same manner as Example
1 The 3-layer bootie was then thermally conformed by loosely
placing the bootie onto a conventional ladies 230 size casual shoe
asymmetrical last and heating the bootie and last in an air
circulating oven at 140.degree. C. for 30 min. During this thermal
dwell, the bootie closely conformed to the shape and size of the
conventional, asymmetrical last, thereby forming a smooth and close
fitting shoe insert to the last. The last was removed from the oven
and allowed to cool to less than 50.degree. C., after which the
shoe insert was removed from the conventional, asymmetric last.
[0249] During shoe production, the conformed shoe insert was placed
on the 230 size casual shoe last to form a smooth and close fit
around the last with no seams, noticeable wrinkles, or excess
material. The shoe insert was then cut and trimmed around the heel
collar area to ensure the shoe insert pattern was correctly
sized.
[0250] The shoe insert was then removed from the last and attached
to the leather upper materials of the casual shoe by stitching the
shoe insert to the collar portion of the upper. The upper materials
and stitched liner were then repositioned onto the 230 size casual
shoe last and a solvent based chloroprene rubber adhesive was
placed on the heel and toe areas (8250 supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea) and sole (8700H supplied by Henkel Technologies Korea,
604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). A protective
EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M. Co., Ltd
#520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to the
insole board (A TEX 6331 supplied by Dong Bo S.M. Co., Ltd #520-36
Gouebob-dong Sang-Gu, Busan, Korea) using a solvent based
chloroprene rubber adhesive (8700H supplied by Henkel Technologies
Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA
protective layer was then attached to the sole of the shoe insert.
The upper materials were then lasted around the shoe insert and
attached insole board. Finally, a rubber sole was attached to the
insole of the shoe insert using a solvent based polyurethane
adhesive (6190S, part number ZY30204093, commercially available
from Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,
Saha-Ku, Busan, Korea) to complete the shoe construction.
[0251] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 3.5 g/hr.
[0252] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard,
showing no water leaks after 30 min.
[0253] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of the fit of the shoe insert
showed that no folds, wrinkles or seams were present to compromise
comfort fit characteristics of the shoes.
Comparative Example 4
[0254] Women's casual shoes were made with natural split suede
leather upper materials suitable for a casual shoe (part number
JS120130501, commercially available from J. S. IND Co., Ltd.
#1086-9, Janglim-Dong, Saha-Ku, Busan, Korea). The upper materials
were stitched together to form the upper of the casual shoes. A 0.6
mm toe puff (part number TFL060, commercially available from Han
Young Industry Co., Ltd, #394-5 Samrak-dong Sasang-Gu, Busan,
Korea) and a 1.7 mm leather board heel counter (supplied by Young
Poly Chemical Co. Ltd. #907-7 Manduck 3-dong Buk-Gu, Busan, Korea)
were then attached to the upper of the shoe.
[0255] A shoe insert made of a laminate of expanded
polytetrafluoroethylene and a textile (part number VISI001001B,
commercially available from W.L. Gore and Associates Inc., Elkton,
Md.). The laminate was cut and stitched together to form a shoe
insert having the size and shape of a 230 size casual shoe last.
GORE-SEAMS tape (commercially available from W.L. Gore and
Associates Inc., Elkton, Md.) was then applied to the stitched
seams to form a waterproof seam over the stitched seams of the shoe
insert. The shoe insert was then placed on the 230 size casual shoe
last which formed a reasonable fit around the last, although
wrinkles and excess material were observed.
[0256] The liner was removed from the casual shoe last and attached
to the leather upper materials of the casual shoe by stitching the
liner to the collar portion of the upper. The upper materials and
stitched liner were then repositioned onto the 230 size casual shoe
last and a solvent based chloroprene rubber adhesive was placed on
the heel and toe areas (8250 supplied by Henkel Technologies Korea,
604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area
(8700H supplied by Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea).
[0257] A protective EVA layer (2.0 mm, hardness 55 supplied by Dong
Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was
adhered to the insole board (A TEX 6331 supplied by Dong Bo S.M.
Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) using the
solvent based chloroprene rubber adhesive (8700H supplied by Henkel
Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,
Korea). The EVA protective layer was then attached to the sole of
the shoe insert. The upper materials were then lasted around the
shoe insert and attached insole board. Finally, a rubber sole was
attached to the insole of the shoe insert using a solvent based
polyurethane adhesive (6190S, part number ZY30204093), commercially
available from Henkel Technologies Korea, 604-030, 472
Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoe
construction.
[0258] Selected shoes were then tested for water vapor permeability
(breathability) using the Whole Boot Water Vapor Permeability test
method outlined above in the whole boot moisture vapor transmission
rate test. The average water vapor permeability was determined to
be 3.6 g/hr.
[0259] The selected shoes were then tested for waterproofness
according to the Centrifuge Test for Waterproofness described
above. The selected footwear met the waterproofness standard
showing, no water leaks after 30 min.
[0260] Basic hand assessment of the surface characteristics of the
inner shoe to assess the degree of fit of the shoe insert showed
that significant folds, wrinkles and seams were present, especially
in the toe areas that would be expected to compromise comfort fit
characteristics of the shoes.
Example 8
[0261] A symmetrical nylon foot last was fixed onto a clamp which
can be rotated through an angle of approximately 140.degree. using
a pneumatic cylinder. A polyurethane adhesive web (UT8, 20
g/m.sup.2 polyurethane non-woven hot melt adhesive obtained from
Protechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was
applied to one side of a commercially available men's dress sock of
65% spun silk and 35% polyamide (Windsor Collection Dress Sock
Large available through Amazon.com) using a heat press set at
130.degree. C. and effective pressure of 34 psi. It was noted that
the sock construction has heel and toe areas reinforced with
additional, thicker material. In addition to the heel and toe
reinforcement, the sock had an angled heel which produced a more
foot-like shape. The sock with the polyurethane adhesive web
thereon was positioned tightly over the last. The sock was applied
to the last with the adhesive web exposed on the outer surface of
the last. Care was taken when applying the sock to the last to
avoid wrinkles.
[0262] A portion of the expanded PTFE tape produced in Example 1
having a length of approximately 1 meter and a width of
approximately 7.4 cm was obtained and fixed in a frame by placing
the tape edges between six toggle clamps positioned along each tape
edge and compressing the PTFE tape between two rubber seals. To
ensure that the width of the tape remained fixed, each tape edge
and clamp assembly was fixed to the frame using locking nuts. The
secured tape in the frame had a width of 6.9 cm. The PTFE tape
fixed in the frame was then heated using an industrial air heater
for approximately 20 seconds during which the tape reached a
temperature of 40-50.degree. C. The locking nuts were then released
and the edges of the tape were slowly, manually moved apart slowly
in the width direction until the tape was expanded to a width of
37.1 cm. To prevent shrink back of the tape and to maintain the
tape width, the frame edges were then secured again using the
locking nuts.
[0263] After the tape was expanded in the width direction and
secured using the locking nuts, the tape was then heated using the
industrial hand held air heater, during which the tape reached a
temperature of approximately 70.degree. C.
[0264] The frame containing the expanded PTFE tape was then removed
from the heat and positioned above the symmetrical last. The
pneumatic cylinder was then activated to allow the symmetrical last
having thereon the sock and adhesive to rotate upwardly at an angle
of 90.degree. to penetrate and deform the preheated PTFE tape
around the last. The final deformation of the tape was completed by
hand to ensure that the tape was deformed closely to the shape of
the last and to minimize wrinkles.
[0265] A second commercially available commercially available men's
dress sock of 65% spun silk and 35% polyamide (Windsor Collection
Dress Sock Large available through Amazon.com) having thereon a
polyurethane adhesive web (UT8, 20 g/m.sup.2 polyurethane non-woven
hot melt adhesive obtained from Protechnic, 41 Avenue Montaigne,
F-68700, Cernay, France) was then placed over the deformed PTFE
tape with the polyurethane adhesive positioned in direct contact
with the surface of the deformed expanded PTFE. Care was taken to
minimize wrinkling of the PTFE tape and the sock.
[0266] The 3-layer article (sock/deformed expanded PTFE tape/sock)
was then secured at the collar of the last using an elastomeric
retaining band to prevent further movement. The complete assembly
of the 3-layer article and nylon last was then placed in an oven
set at 140.degree. C. for a time of 30 min. During this thermal
dwell, the last reached an approximate temperature of 110.degree.
C. The assembly was then removed and a vacuum bag was quickly
applied over the assembly. A vacuum was applied at 27 inches Hg
until the assembly had cooled to approximately 50.degree. C. to
ensure good contact between the three layers and subsequent
adhesive bonding between the socks and expanded PTFE tape layer.
The vacuum was then removed from the assembly. The vacuum bag and
elastomeric retaining band were then removed from the last and the
completed 3-layer bootie was slowly removed from the last.
[0267] The 3-layer bootie was then tested for water vapor
permeability (breathability) using the Whole Boot Water Vapor
Permeability test method outlined above in the moisture vapor
transmission rate. The average water vapor permeability was
determined to be 16.5 g/hr.
[0268] The 3-layer shoe insert perform was then tested for
waterproofness according to the Modified Centrifuge Test for
waterproofness described above. The selected footwear met the
waterproofness standard, showing no water leaks after 60 min.
Example 9
[0269] A 3-layer bootie was prepared as outlined above in Example 8
and then thermally conformed by loosely placing the bootie onto a
men's 265 size running shoe last and then placing the bootie in an
air circulating oven at 140.degree. C. for 30 min. During this
thermal dwell, the liner closely conformed to the shape and size of
the last, forming a smooth and close fitting shoe insert to that of
the running show last, particularly in the heel area up to the
ankle height of the shoe. FIG. 9 is a schematic illustration
depicting the shoe insert (dotted lines) on the running shoe last
after the shoe insert was conformed. The last was removed from the
oven and allowed to cool to less than 50.degree. C., after which
the liner was removed from the last.
[0270] The conformed 3-layer bootie was tested for water vapor
permeability (breathability) using the Whole Boot Water Vapor
Permeability test method outlined above in the moisture vapor
transmission rate test and with the expanded membrane layer being
exposed on the upper surface. The average water vapor permeability
was determined to be 19.6 g/hr.
[0271] The conformed 3-layer bootie was then tested for
waterproofness according to the Modified Centrifuge Test for
Waterproofness described above. The selected footwear met the
waterproofness standard showing no water leaks after 60 min.
Example 10
[0272] A symmetrical aluminum foot last was fixed onto a clamp
which can be rotated through an angle of approximately 140.degree.
using a pneumatic cylinder. An expanded PTFE tape made generally in
accordance with the teachings set forth in U.S. Pat. No. 7,306,729
to Bacino, et al. having a length of approximately 1 meter and a
width of approximately 7.4 cm was fixed in a frame by placing the
edges of the tape between six toggle clamps positioned along the
tape edges and compressing the tape between two rubber seals. To
ensure that the width of the tape remained fixed, the tape edges
and clamp assembly were fixed to the frame using locking nuts. The
secured tape in the frame had a width of 6.9 cm.
[0273] The tape fixed in the frame was then heated using an
industrial air heater for approximately 20 seconds during which the
tape reached a temperature of 40-50.degree. C. The locking nuts
were then released and the edges of the tape were slowly manually
moved apart in the width direction until the tape was expanded to a
width of 37.1 cm. To prevent shrink back of the tape and to
maintain the tape width, the frame edges were again secured using
the locking nuts. After the tape was expanded in the width
direction and secured using the locking nuts, the ePTFE tape was
heated using the industrial air heater during which the tape
reached a temperature of approximately 70.degree. C.
[0274] The frame containing the ePTFE tape was then removed from
the heat and positioned above the symmetrical last. The pneumatic
cylinder was then activated to allow the symmetrical to rotate
upwardly at an angle of 90.degree. to penetrate and deform the
preheated PTFE tape around the last. The final deformation of the
tape over the last was completed by hand to ensure that the tape
was deformed closely to the shape of the last and to minimize
wrinkles.
[0275] The symmetrical last and deformed expanded PTFE were then
placed in an oven at 365.degree. C. for 20 minutes to ensure that
the expanded PTFE was "amorphously-locked". The complete assembly
was then removed from the oven and left to cool to room
temperature.
[0276] After cooling, a polyurethane adhesive web (UT8, 20
g/m.sup.2 polyurethane non-woven hot melt adhesive obtained from
Protechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was
applied to one side of a commercially available men's black sock of
60 den (66 dtex) 61% polyamide, 37% cotton and 2% elastane
(Sockchen Naturelle 60 commercially available from Nur Die GmbH,
Rheine, Germany) using a heat press set at 130.degree. C. and
effective pressure of 5 psi. The sock with the polyurethane
adhesive web thereon was positioned tightly over the last with the
adhesive web in direct contact with the ePTFE surface. Care was
taken when applying the sock to the last to avoid wrinkles.
[0277] The 2-layer article (sock-deformed expanded PTFE) was then
secured at the collar of the last using an elastomeric retaining
band to prevent further movement. The complete assembly of the
2-layer article and aluminum last was then placed in an oven set at
140.degree. C. for 45 min. The assembly was then removed and a
vacuum bag was quickly applied over the assembly. A vacuum was
applied at 27 inches Hg until the assembly had cooled to
approximately 50.degree. C. to ensure good contact between the
layers and bonding between the sock and ePTFE layer. The vacuum was
then removed from the assembly. The vacuum bag and elastomeric
retaining band were removed from the last. Finally, the completed
2-layer bootie was slowly and carefully removed from the last.
Example 11
[0278] A symmetrical nylon foot last was fixed onto a clamp which
can be rotated through an angle of approximately 140.degree. using
a pneumatic cylinder. A polyurethane adhesive web (UT8, 20
g/m.sup.2 polyurethane non-woven hot melt adhesive obtained from
Protechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was
applied to one side of a commercially available 60 den (66 dtex)
61% polyamide, 37% cotton and 2% elastane black sock (Sockchen
Naturelle 60 commercially available from Nur Die GmbH, Rheine,
Germany) using a heat press set at 130.degree. C. and effective
pressure of 5 psi. The sock was applied to a symmetrical last with
the adhesive web exposed on the outer surface of the symmetrical
last. Care was taken when applying the sock to the last to avoid
wrinkles.
[0279] A fine powder of PTFE polymer (Daiken Industries, Ltd.,
Orangeburg, N.Y.) was blended with Isopar.RTM. K (Exxon Mobil
Corp., Fairfax, Va.) in the proportion of 0.196 g/g of fine powder.
The lubricated powder was compressed in a cylinder to form a pellet
and placed into an oven set at 70.degree. C. for approximately 12
hours. Compressed and heated pellets were ram extruded to produce
tapes approximately 15.2 cm wide by 0.73 mm thick. Three separate
rolls of tape were produced and layered together between
compression rolls to a thickness of 0.76 cm. The tape was then
transversely stretched to 56 cm (i.e., at a ratio of 3.7:1),
restrained, and then dried in an oven set at 270.degree. C. The dry
tape was longitudinally expanded between banks of rolls over a
heated plate set to a temperature of 340.degree. C. The speed ratio
between the second bank of rolls and the first bank of rolls, and
hence the expansion ratio, was 8:1.
[0280] A portion of the expanded PTFE tape having a length of
approximately 1 meter and a width of approximately 12.5 cm was
fixed in a frame by placing the tape edges between six toggle
clamps positioned along each tape edge and compressing the tape
between two rubber seals. To ensure that the width remained fixed,
the tape edges and the clamp assembly were fixed to the frame using
locking nuts. The secured tape in the frame had a width of 9
cm.
[0281] The tape fixed in the frame was then heated using an
industrial air heater for approximately 20 seconds, during which
the tape reached a temperature of 40-50.degree. C. The locking nuts
were then released and the edges of the tape were slowly, manually
moved apart in the width direction until the tape was expanded to a
width of 27 cm. To prevent shrink back of the tape and to maintain
the 27 cm tape width, the frame edges were again secured using the
locking nuts.
[0282] After the tape was expanded in the width direction and
secured using the locking nuts, the tape was then heated using the
industrial air heater, during which the tape reached a temperature
of approximately 70.degree. C. The pneumatic cylinder was then
activated to allow the symmetrical last having thereon the sock and
adhesive to rotate upwardly at an angle of 90.degree. to penetrate
and deform the preheated PTFE tape around the last. The final
deformation of the tape over the last was completed by hand to
ensure that the tape deformed closely to the shape of the last and
to minimize wrinkles.
[0283] A second sock (60 den (66 dtex) 61% polyamide, 37% cotton
and 2% elastane black sock (Sockchen Naturelle 60 commercially
available from Nur Die GmbH, Rheine, Germany) having thereon a
polyurethane adhesive web was then placed over the deformed tape
with the adhesive positioned in direct contact with the surface of
the deformed expanded PTFE tape. Care was taken when applying the
sock to minimize wrinkling.
[0284] The 3-layer article (sock/deformed expanded PTFE tape/sock)
was then secured at the collar of the last using an elastomeric
retaining band to prevent further movement. The complete assembly
of the 3-layer article and nylon last was then placed in an oven at
150.degree. C. for 30 min. During this thermal dwell, the last
reached an approximate temperature of 120.degree. C. The assembly
was then removed and a vacuum bag was quickly applied over the
assembly. A vacuum was applied (at 27 inches Hg) until the assembly
had cooled to approximately 50.degree. C. to ensure good contact
between the layers and subsequent adhesive bonding between the
socks and expanded PTFE layer. The vacuum was then removed from the
assembly and the vacuum bag removed. The elastomeric retaining band
was removed from the last and the completed sock is slowly removed
from the last. The sock has a high degree of elasticity and can be
subsequently stretched to form a close fitting sock over a broad
range of last sizes, such as, for example, a ladies medium (e.g. EU
size 240) to a men's large (e.g., EU size 275).
[0285] The sock was then tested for water vapor permeability
(breathability) using the Sock Water Vapor Permeability test method
outlined above. The average sock water vapor permeability was
determined to be 26.4 g/hr.
[0286] When the sock was placed in a running shoe, the water vapor
permeability of the shoe and sock was determined to be 11.7
g/hr.
[0287] Selected shoes were then tested for waterproofness according
to the Centrifuge Test for Waterproofness described above. The
selected footwear met the waterproofness standard, showing no water
leaks after 60 min.
Comparative Example 5
[0288] A 275 sized shoe insert made of a laminate of expanded
polytetrafluoroethylene and a textile (part number VISI001001B,
commercially available from W.L. Gore and Associates Inc., Elkton,
Md.) was produced utilizing conventional means. Specifically, the
laminate was cut and stitched together to form the 275 sized sock
insert. GORE-SEAM.RTM. tape (commercially available from W.L. Gore
and Associates Inc., Elkton, Md.) was then applied to the stitched
seams to form a waterproof seam over the stitched seams of the
insert. The sock insert was then tested for water vapor
permeability (breathability) using the Sock Water Vapor
Permeability test method outlined above. The average sock insert
water vapor permeability was determined to be 17.7 g/hr.
[0289] The sock was then tested for waterproofness according to the
Centrifuge Test for Waterproofness described above. The sock met
the waterproofness standard, showing no water leaks after 60
min.
Comparative Example 6
[0290] For comparative water vapor transmission rate and
waterproofness testing, a commercially available large size
waterproof and breathable sock was obtained (Seal Skinz Thin
Socklet from Seal Skinz Ltd, 36 Oldmedow Road, Norfolk, PE30 3PP,
United Kingdom).
[0291] The sock was tested for water vapor permeability
(breathability) using the test method outlined above in the sock
moisture vapor transmission rate test. The average sock water vapor
permeability was determined at 11.8 g/hr. When the sock was placed
in a running shoe, the water vapor permeability of the shoe and
sock was determined to be 6.6 g/hr.
[0292] The sock was then tested for waterproofness according to the
Centrifuge Test for Waterproofness described above. The sock did
not meet the waterproofness standard showing water leaks after 15
minutes.
[0293] The invention of this application has been described above
both generically and with regard to specific embodiments. Although
the invention has been set forth in what is believed to be the
preferred embodiments, a wide variety of alternatives known to
those of skill in the art can be selected within the generic
disclosure. The invention is not otherwise limited, except for the
recitation of the claims set forth below.
* * * * *