U.S. patent application number 14/577022 was filed with the patent office on 2015-06-25 for self sealing system for waterproof coupling of uppers to outsoles.
The applicant listed for this patent is Columbia Sportswear North America, Inc.. Invention is credited to Xiao Dong Liu, Yi Jiang Wei, Peng Cheng Xia.
Application Number | 20150173453 14/577022 |
Document ID | / |
Family ID | 53398690 |
Filed Date | 2015-06-25 |
United States Patent
Application |
20150173453 |
Kind Code |
A1 |
Liu; Xiao Dong ; et
al. |
June 25, 2015 |
SELF SEALING SYSTEM FOR WATERPROOF COUPLING OF UPPERS TO
OUTSOLES
Abstract
Disclosed herein are waterproof footwear, footwear that include
a waterproofed stitch line, and methods of waterproofing a stitch
line in footwear. Methods are provided for waterproofing a seam in
an article of footwear by positioning co-extruded top-welt/rubber
tape comprising a rubber tape layer and a top-welt layer between
the layers to be stitched, and stitching the seam so that it passes
through the co-extruded top-welt/rubber tape.
Inventors: |
Liu; Xiao Dong; (Zhuhai
City, CN) ; Wei; Yi Jiang; (Zhuhai City, CN) ;
Xia; Peng Cheng; (Zhuhai City, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Columbia Sportswear North America, Inc. |
Portland |
OR |
US |
|
|
Family ID: |
53398690 |
Appl. No.: |
14/577022 |
Filed: |
December 19, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61919427 |
Dec 20, 2013 |
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Current U.S.
Class: |
36/4 ;
12/142E |
Current CPC
Class: |
A43B 7/12 20130101; A43B
9/02 20130101 |
International
Class: |
A43B 7/12 20060101
A43B007/12; A43B 1/10 20060101 A43B001/10 |
Claims
1. A waterproof footwear seam comprising: a shell outsole; an
upper; a co-extruded top-welt/rubber tape comprising a rubber tape
layer and a top-welt layer, wherein the co-extruded top-welt/rubber
tape is positioned between the shell outsole and the upper such
that the rubber tape layer of the co-extruded top-welt/rubber tape
is positioned between the shell outsole and the top-welt layer of
the co-extruded top-welt/rubber tape; and at least one line of
stitching passing through the shell outsole, the co-extruded
top-welt/rubber tape, and the upper.
2. The waterproof footwear seam of claim of claim 1, wherein the
rubber tape layer comprises synthetic rubber, natural rubber, or a
rubber composite.
3. The waterproof footwear seam of claim of claim 1, wherein the
rubber tape layer comprises a polymer.
4. The waterproof footwear seam of claim 1, wherein the upper
comprises leather.
5. An article of footwear comprising the waterproof footwear seam
of claim 1.
6. A method of waterproofing a footwear seam comprising:
positioning a co-extruded top-welt/rubber tape comprising a rubber
tape layer and a top-welt layer along an upper edge of a shell
outsole, such that the rubber tape layer is positioned between the
top-welt layer and an outer surface of the upper shell; positioning
a footwear upper such that the shell outsole and the footwear upper
overlap with the co-extruded top-welt/rubber tape positioned
therebetween; forming a seam between the shell outsole and the
footwear upper, wherein the seam passes through the co-extruded
top-welt/rubber tape; and at least partially curing the rubber tape
layer.
7. The method of claim 6, further comprising forming the
co-extruded top-welt/rubber tape.
8. The method of claim 6, further comprising partially vulcanizing
the rubber tape layer.
9. The method of claim 8, wherein the rubber tape layer is
partially vulcanized prior to positioning the co-extruded
top-welt/rubber tape along the upper edge of the shell outsole.
10. The method of claim 8, wherein the rubber tape layer is
partially vulcanized after the co-extruded top-welt/rubber tape is
positioned along the upper edge of the shell outsole.
11. The method of claim 6, wherein the rubber tape layer comprises
synthetic rubber, natural rubber, or a rubber composite.
12. The method of claim 6, wherein the rubber tape layer comprises
a polymer.
13. The method of claim 6, wherein forming the seam comprises
stitching the seam.
14. The method of claim 6, wherein positioning the co-extruded
top-welt/rubber tape along the upper edge of the shell outsole
comprises coupling the co-extruded top-welt/rubber tape to the
shell outsole with adhesive.
15. The method of claim 6, wherein the footwear upper comprises
leather.
16. The method of claim 6, wherein at least partially curing the
rubber tape layer comprises heating the rubber tape layer.
17. The method of claim 16, wherein heating the rubber tape layer
comprises heating the rubber tape layer to a temperature of about
50-100.degree. C.
18. The method of claim 16, wherein heating the rubber tape layer
comprises heating the rubber tape layer to a temperature of about
70-85.degree. C. for about 5-10 minutes.
19. An article of footwear made by the method of claim 6.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional
Patent Application No. 61/919,427, filed Dec. 20, 2013, entitled
"Self Sealing Vulcanized System for Waterproofing Uppers to Shell
Outsoles," the disclosure of which is hereby incorporated by
reference in its entirety.
TECHNICAL FIELD
[0002] Embodiments herein relate to the field of waterproofing,
and, more specifically, to waterproof footwear and methods of
waterproofing a stitch line in footwear.
BACKGROUND
[0003] Many types of footwear and other outerwear have seams that
must be sealed for waterproofing, and many types of self-sealing
seam construction techniques have been proposed. One such approach
is to apply a cover strip or tape made from any of various
materials over the seam after it has been formed. However, such
tapes can be difficult to place properly and can leak. In other
instances, multiple layers of sealing cement may be applied over
the seam in a process referred to as "gunking." Though effective,
the gunking procedure is labor-intensive and time-consuming.
Additionally, gunking may result in hardening of the upper areas
and contamination of the cement with dirt and/or debris once it has
been applied to the footwear.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Embodiments will be readily understood by the following
detailed description in conjunction with the accompanying drawings.
Embodiments are illustrated by way of example and not by way of
limitation in the figures of the accompanying drawings.
[0005] FIG. 1 illustrates a method of coupling rubber tape to a
footwear upper, in accordance with various embodiments;
[0006] FIG. 2 illustrates a footwear upper and outsole shell ready
for assembly, in accordance with various embodiments;
[0007] FIG. 3 illustrates an assembled boot in which the seam has
been sealed, in accordance with various embodiments;
[0008] FIG. 4 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments;
[0009] FIG. 5 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 4, plus one
additional step, in accordance with various embodiments;
[0010] FIG. 6 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 5, plus one
additional step, in accordance with various embodiments;
[0011] FIG. 7 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 6, plus one
additional step, in accordance with various embodiments;
[0012] FIGS. 8A and 8B illustrate an alternate method of forming a
waterproof seam between a footwear upper and a shell outsole,
wherein FIG. 8A illustrates a footwear upper, top welt, and outsole
shell ready for assembly, and FIG. 8B illustrates the footwear
upper, top welt, and outsole shell of FIG. 8A after assembly and
stitching, in accordance with various embodiments;
[0013] FIGS. 9A-9C illustrate three steps in the alternate method
shown in FIG. 8A, including a close-up view of the rubber tape side
of a co-extruded top-welt/rubber tape (FIG. 9A), a cross-sectional
view of a co-extruded top-welt/rubber tape that has been coupled to
an outsole shell (FIG. 9B), and a cross sectional view of the
top-welt/rubber tape and outsole shell of FIG. 9B after the
footwear upper has been coupled and stitched into place with the
stitching passing through the leather upper, top-welt/rubber tape,
and outsole shell (FIG. 9C), in accordance with various
embodiments;
[0014] FIG. 10 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments;
[0015] FIG. 11 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 10, plus one
additional step, in accordance with various embodiments;
[0016] FIG. 12 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 11, plus one
additional step, in accordance with various embodiments; and
[0017] FIG. 13 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, which method
corresponds to the method illustrated in FIG. 12, plus one
additional step, in accordance with various embodiments.
DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS
[0018] In the following detailed description, reference is made to
the accompanying drawings which form a part hereof, and in which
are shown by way of illustration embodiments that may be practiced.
It is to be understood that other embodiments may be utilized and
structural or logical changes may be made without departing from
the scope. Therefore, the following detailed description is not to
be taken in a limiting sense, and the scope of embodiments is
defined by the appended claims and their equivalents.
[0019] Various operations may be described as multiple discrete
operations in turn, in a manner that may be helpful in
understanding embodiments; however, the order of description should
not be construed to imply that these operations are order
dependent.
[0020] The description may use perspective-based descriptions such
as up/down, back/front, and top/bottom. Such descriptions are
merely used to facilitate the discussion and are not intended to
restrict the application of disclosed embodiments.
[0021] The terms "coupled" and "connected," along with their
derivatives, may be used. It should be understood that these terms
are not intended as synonyms for each other. Rather, in particular
embodiments, "connected" may be used to indicate that two or more
elements are in direct physical contact with each other. "Coupled"
may mean that two or more elements are in direct physical contact.
However, "coupled" may also mean that two or more elements are not
in direct contact with each other, but yet still cooperate or
interact with each other.
[0022] For the purposes of the description, a phrase in the form
"A/B" or in the form "A and/or B" means (A), (B), or (A and B). For
the purposes of the description, a phrase in the form "at least one
of A, B, and C" means (A), (B), (C), (A and B), (A and C), (B and
C), or (A, B and C). For the purposes of the description, a phrase
in the form "(A)B" means (B) or (AB) that is, A is an optional
element.
[0023] The description may use the terms "embodiment" or
"embodiments," which may each refer to one or more of the same or
different embodiments. Furthermore, the terms "comprising,"
"including," "having," and the like, as used with respect to
embodiments, are synonymous.
[0024] In various embodiments, methods, apparatuses, and systems
for waterproofing a stitch line in footwear are provided. Some
types of footwear, such as boots and shoes, may be constructed by
securing an upper portion to a shell outsole. In various
embodiments, the seam between the upper and the shell outsole may
be stitched, creating a secure junction, but also creating a stitch
line for which waterproofing may be desired. In many applications,
this seam line may be waterproofed by applying successive layers of
adhesives in a process referred to as gunking. Though effective,
gunking is time consuming and may cause manufacturing bottlenecks
and/or hardening of portions of the uppers.
[0025] Disclosed herein are methods for waterproofing a stitch line
or other seam in an article of footwear that may eliminate or
reduce the number of gunking layers that are needed to achieve a
waterproof seam. In some embodiments, a layer of tape that includes
uncured natural or synthetic rubber (or a combination thereof) may
be included between the outsole (such as a shell outsole) and the
upper. In some embodiments, the seam may be stitched or otherwise
fixed in place by fastening elements, forming a seam with the tape
layer positioned between the outsole and the upper, and with the
stitching passing through all three of the upper, uncured rubber
tape, and outsole. In some embodiments, the resulting seam (or the
entire article of footwear) may be heated to at least partially
cure the rubber and/or to allow the rubber tape to at least
partially flow into empty spaces, thus forming a waterproof,
water-resistant, and/or water-tight seam.
[0026] In alternate embodiments, a layer of tape that includes
natural or synthetic rubber (or a combination thereof) may be
co-extruded with a top-welt. For the purposes of the present
description, the term "co-extruded" refers to the simultaneous
extrusion of two or more different yet compatible elements or
materials through the same die/extruder. The top-welt may then be
fixed to an outer surface of the shell outsole, for instance with
the rubber tape layer sandwiched between the shell outsole and the
top-welt. In some environments, the upper may then be stitched or
otherwise fixed in place via fastening elements, with the seam
between the shell outsole and the upper passing through all four of
the upper, top-welt, rubber tape, and outsole layers.
[0027] In various embodiments, positioning the top-welt between the
upper and the rubber tape may limit the degree to which the rubber
tape may flow through the holes created by the stitching.
Optionally, in some embodiments, once the top-welt has been
positioned on the shell outsole, the rubber tape may be partially
vulcanized prior to stitching, for instance if it is desirable to
further reduce flowability of the rubber tape layer.
[0028] In various embodiments, this method may be advantageous
because the co-extrusion process of forming the top-welt and rubber
tape layers may avoid human error (e.g., inconsistencies in
positioning) that may occur when the rubber tape alone is affixed
to the shell outsole. Additionally, positioning the top-welt
between the rubber tape and the upper may limit the extent to which
the rubber tape may flow through the stitch holes to the exterior
surface of the upper, which may cause cosmetic issues. Furthermore,
preventing direct contact between the rubber tape layer and the
upper, when the upper is made from leather, may prevent oil from
the leather from contacting the rubber tape, which may adversely
impact the waterproofing function of the rubber tape and/or
undesirably increase the flowability of the rubber tape,
particularly in hot conditions. Additionally, the co-extruded
top-welt/rubber tape may be soft and elastic, and may function as a
sealing spacer between the shell outsole and the upper.
[0029] In various embodiments, the disclosed methods may create a
seal that meets or exceeds the waterproof testing requirements
typically applied to footwear manufactured using a standard gunking
technique. Additionally, in various embodiments, the methods may be
used to waterproof any seam, including those not normally subjected
to the gunking process. Furthermore, although the examples
illustrated herein depict a leather upper coupled to a rubber shell
outsole, one of skill in the art will appreciate that various
materials may be joined in accordance with the embodiments
described herein. For example, the methods may be used to
waterproof a seam between layers of leather, plastic, rubber,
natural fabric, synthetic fabric, and/or other natural or synthetic
materials.
[0030] In various embodiments, the uncured rubber tape may include
any rubber or synthetic rubber compound or composite that may be
cured with the application of heat or at room temperature. For
instance, in various embodiments, the uncured rubber compound may
include synthetic rubber, natural rubber, other polymers, or a
combination thereof, as well as additional fillers, activators,
accelerators, sulfur compounds, anti-oxygen compounds, etc.
Specific, non-limiting examples of rubber compounds that may be
used include isoprene rubber (I), butyl rubber (IIR), neoprene
rubber (CR), butadiene rubber (BR), styrene-butadiene rubber (SBR),
solution styrene-butadiene rubber (SSBR), and nitrile butadiene
rubber (NBR). Without being bound by theory, applying the rubber
tape to the footwear in the uncured state may allow the rubber to
at least partially flow into small spaces between the footwear
layers and/or into the holes created in the footwear layers by the
stitching and/or other fastening elements. In some embodiments, the
rubber may then be allowed to cure naturally, or curing may be
accelerated by the application of heat. In some embodiments, the
rubber tape may be partially vulcanized before being applied to the
outsole, particularly in situations wherein it is desirable to
limit or control flowability.
[0031] In some examples, the uncured rubber tape (or the
co-extruded top-welt/rubber tape) may be about 10-30 mm wide, for
example, about 12, 14, 16, 18, 20, 22, 24, 26, or 28 mm wide. In
some examples, the uncured rubber tape (or the rubber tape portion
of the co-extruded top-welt/rubber tape) may have a thickness of
from about 0.5 mm to about 1.5 mm, for example, about 0.6 mm, about
0.8 mm, about 1.0 mm, or about 1.2 mm thick. In specific
embodiments, the rubber tape (or the rubber tape portion of the
co-extruded top-welt/rubber tape) may also include one or more
polymers adapted to add flexibility, flowability, stretch,
resilience, strength, or another desired property. In particular
embodiments, the uncured rubber tape (or the rubber tape portion of
the co-extruded top-welt/rubber tape) may be a single, uniform
layer of uncured rubber (with or without additional polymers) with
no additional backing layer or other layers.
[0032] In various embodiments, the uncured rubber tape (or the
rubber tape portion of the co-extruded top-welt/rubber tape) may be
coupled to the footwear upper and/or shell outsole using adhesive
or cement. In specific, non-limiting examples, the cement may
include polyurethane cement, hotmelt cement, CR cement, CR-grafted
adhesive, latex adhesive, natural rubber paste, synthetic rubber
paste, or a combination thereof. In one specific, non-limiting
embodiment, a strip of cement may be applied to the inside edge of
an upper and/or one side of the uncured rubber tape, and the
uncured rubber tape may be applied to the inside edge of the
leather upper. In some embodiments, a corresponding strip of cement
may be applied to the outside edge of the shell outsole in
preparation for receiving the uncured rubber tape when coupled to
the upper. In some embodiments, a hammer, roller, or other device
may be used to flatten or smooth the tape or the co-extruded
top-welt/rubber tape into position once it has been applied to the
upper.
[0033] In another specific, non-limiting embodiment, a strip of
cement may be applied to the outside edge of a shell outsole and/or
one side of the uncured rubber tape, and the uncured rubber tape
may be applied to the outside edge of the shell outsole. In various
embodiments, a corresponding strip of cement may be applied to the
inside edge of the upper in preparation for receiving the uncured
rubber tape when coupled to the shell outsole. In some embodiments,
a hammer, roller, or other device may be used to flatten or smooth
the tape into position once it has been applied to the shell
outsole.
[0034] In another specific, non-limiting embodiment, a strip of
cement may be applied to the top outside edge of shell outsole
and/or one side of the rubber tape portion of the co-extruded
top-welt/rubber tape, and the rubber tape portion of the
co-extruded top-welt/rubber tape may then be applied to the top
outside edge of the shell outsole. In various embodiments, a
corresponding strip of cement may be applied to the inside edge of
the upper in preparation for receiving the uncured rubber tape when
coupled to the shell outsole. In some embodiments, a hammer,
roller, or other device may be used to flatten or smooth the
co-extruded top-welt/rubber tape into position once it has been
applied to the shell outsole.
[0035] In some embodiments, the strip of cement or other adhesive
may be the same width as the uncured rubber tape (or the rubber
tape portion of the co-extruded top-welt/rubber tape), whereas in
other embodiments, the strip of cement may be slightly wider than
the width of the uncured rubber tape (or the rubber tape portion of
the co-extruded top-welt/rubber tape). In one specific,
non-limiting embodiment, the rubber tape (or the rubber tape
portion of the co-extruded top-welt/rubber tape) may have a width
of about 20 mm and the strip of cement may have a width of about 25
mm. In various embodiments, the cement strip may be applied using a
brush, a roller, or any other known applicator.
[0036] In various embodiments, once the upper and shell outsole are
coupled with the uncured rubber tape positioned between the two
layers, or with the co-extruded rubber tape/top-welt positioned
between the shell outsole and the upper, the layers may be stitched
or otherwise coupled together, for instance using a plurality of
fastening elements such as grommets or tacks. In one specific,
non-limiting example, the upper may be stitched to the shell
outsole (e.g., through the tape and/or top-welt), for instance
using a conventional sewing machine known to those of skill in the
art. In various embodiments, stitching the layers together may
compress the uncured rubber tape (or the rubber tape portion of the
co-extruded top-welt/rubber tape), causing it to flow into and fill
any open spaces, such as needle holes, between the layers. In
particular embodiments, the compression produced by the stitching
also may apply sufficient force to cause the uncured rubber tape
(or the rubber tape portion of the co-extruded top-welt/rubber
tape) to flow at least partially into the holes created by the
needle and thread. In various embodiments, this process may result
in a waterproof, watertight, and/or water-resistant seam.
[0037] In various embodiments, the co-extruded rubber tape/top-welt
may be partially vulcanized prior to affixing the co-extruded
top-welt/rubber tape to the shell outsole. In other embodiments,
the entire shell outsole and co-extruded top-welt/rubber tape may
be partially vulcanized after the co-extruded top-welt/rubber tape
has been affixed to the shell outsole. In various embodiments, this
partial vulcanization may be desirable, for example to limit the
flowability of the rubber tape, such as in hot conditions.
[0038] In various embodiments, following stitching, additional heat
may be applied to the rubber tape (or co-extruded top-welt/rubber
tape) to accelerate curing of the rubber and/or to assist the tape
to flow into empty spaces and create a waterproof seal. Without
being bound by theory, curing of the rubber may allow the rubber
tape (or the rubber tape portion of the co-extruded top-welt/rubber
tape) to be fixed in position, and may prevent further flowing of
the rubber. In some embodiments, the tape (or the rubber tape
portion of the co-extruded top-welt/rubber tape) may be heated to
about 50.degree. C., for example, about 65.degree. C., about
70.degree. C., about 75.degree. C., about 80.degree. C., about
85.degree. C., about 90.degree. C., about 100.degree. C., or an
even higher temperature. In some embodiments, this may be
accomplished by applying heat directly to the seam, whereas in
other embodiments, the footwear may be heated in an oven, under a
heat lamp, or by any other radiant heat source. In one specific,
non-limiting example, the footwear may be passed through a heating
tunnel for about 5-15 minutes at a temperature for about
80-85.degree. C., which may result in a footwear temperature of
about 78.degree. C. In some embodiments, following heating, the
seam may be further compressed using a hammer, roller, or other
flattening device.
[0039] In various embodiments, one or more gunking adhesive layers
may be applied to other parts of the footwear where additional
waterproofing is desired, such as the heel and/or vamp regions of
the upper. In various embodiments, these regions may be gunked
prior to or after the seam has been taped, stitched, and/or heated.
In other embodiments, the taped, sealed seam may be further
waterproofed by applying one or more layers of gunking adhesive
using conventional methods. For instance, in some embodiments, a
layer of gunking adhesive may be applied to the interior surface of
the taped, sealed seam either before or after the footwear is
heated. In particular embodiments, one or more subsequent layers of
gunking adhesive may be added if further waterproofing is desired.
However, one of skill in the art will recognize that in various
embodiments, such additional gunking steps may not be required in
order to meet the desired waterproofing standard.
[0040] FIG. 1 illustrates a method of coupling rubber tape to a
footwear upper, in accordance with various embodiments. In the
illustrated embodiment, the footwear upper 100 has been turned
inside out so that the inner surface may be accessed. In some
embodiments, one or more layers of gunking adhesive (not shown) may
be applied to the inside vamp and heel regions of the leather upper
portion of the footwear upper at this stage. In various
embodiments, this gunking adhesive may include a CR-based adhesive,
polyurethane cement, hotmelt adhesive, CR cement, CR-grafted
adhesive, latex adhesive, natural rubber paste, synthetic rubber
paste, or a mixture thereof. As shown in FIG. 1, a strip of cement
102 may then be applied to the inner, bottom edge of footwear upper
100, for example when footwear upper 100 is configured to overlap
the shell outsole (not shown) on the outside surface of the
outsole. In other embodiments, wherein footwear upper 100 is
configured to overlap the shell outsole on the inside surface, the
cement would be applied to the outer surface of footwear upper 100,
instead.
[0041] In the illustrated example, the width of cement strip 102 is
about 20-25 mm, however, one of skill in the art will appreciate
that cement strip 102 may be of any width sufficient to couple
uncured rubber tape 104 to footwear upper 100. In particular
embodiments, the cement may comprise GL-033N/NW cement, although
one of skill in the art will appreciate that many different
suitable cements may be substituted. In some embodiments, a
corresponding strip of primer, such as NP11 primer, also may be
applied to uncured rubber tape 104. Although the method as
disclosed herein describes applying cement to footwear upper 100
and primer to uncured rubber tape 104, one of skill in the art will
appreciate that in other embodiments, primer may be applied to
footwear upper 100 and cement may be applied to uncured rubber tape
104. In still other embodiments, cement may be applied to both
components.
[0042] In various embodiments, a narrow strip of uncured synthetic
and/or natural rubber may be cut from a larger piece to create
uncured rubber tape 104. In some embodiments, cement adhesive may
be applied directly to uncured rubber tape 104 and/or to the
portion of the footwear to which uncured rubber tape 104 will be
affixed, and uncured rubber tape 104 may then be attached to the
lower inside edge 106 of footwear upper 100 as illustrated in FIG.
1. In some embodiments, a hammer or roller may be used to flatten
uncured rubber tape 104, and footwear upper 100 may be turned
right-side-out.
[0043] FIG. 2 illustrates a footwear upper and outsole shell ready
for assembly, in accordance with various embodiments. As
illustrated, in various embodiments, footwear upper 100 may be
turned right side out and uncured rubber tape 104 may be positioned
to rest between lower inside edge 106 of footwear upper 100 and
upper outside edge 108 of outsole shell 110 when the footwear is
assembled.
[0044] FIG. 3 illustrates an assembled boot in which the seam has
been sealed, in accordance with various embodiments. In various
embodiments, the taped footwear upper 100 may be fastened to
outsole shell 110 using conventional methods. As illustrated, in
some embodiments, one or more rows of stitching 112 may be used,
for example one, two, or three rows of stitching. Once stitched,
seam 114 may be set by curing rubber tape 104 to waterproof seam
114, in accordance with various embodiments. In some embodiments,
the taped, stitched footwear may be heated, for example in a
heating tunnel, at a temperature of about 80-85.degree. C. In one
specific, non-limiting example, the heated footwear may reach a
temperature of approximately 78.degree. C. after heating for about
8 minutes. In some embodiments, a hammer or other tool may be used
to flatten and secure seam 114 following heating.
[0045] In some embodiments, the rubber tape used in various
embodiments may conform to a desired set of properties, such as
hardness, thickness, density, tensile strength, and the like. One
specific, non-limiting set of desired properties is illustrated in
Table 1, below. One of skill in the art will appreciate that other
properties may be desirable for other applications.
TABLE-US-00001 TABLE 1 Property Test Method Hardness Before Curing
Hardness (Ask C) SATRA TM205 1.0-1.2 MM ASTM D-2240 Thickness / T2:
6-9M; T90: Ignored Rheometer Test 130 T2: 6-9M; T90: Ignored After
Curing Hardness (Shore A) SATRA TM205 1.30-1.40 ASTM D-2240 Density
(g/cm.sup.3) SATRA TM134 Min30 ASTM D-297 Tensile strength
(kg/cm.sup.2) SATRA TM137 Min450 test ASTM D-412 Elongation at
break (%) SATRA TM137 50,000 no damage ASTM D-412 Ross flex (no
more than 2 SATRA TM60 15,000 pass mm cut, after number of ASTM
D-1052 flexes at -20.degree. C.) Water-proof test (Cycles) SATRA TM
77
[0046] In some embodiments, different formulations of the rubber
tape may be selected for different purposes. Table 2 illustrates
two specific, non-limiting examples of rubber tape formulations
that may be used.
TABLE-US-00002 TABLE 2 Raw Materials Formula 1 Formula 2 POLYMERS
70 (ADSL) STR 3L 100 (3L) 30 (IR 3S) ZnO 4 4 S-80 (sulfur-based
rubber 2.3 0.4 vulcanizing agent) MBT-80 (e.g., agglutination 0.3
(MBT-80) 0.7 (F) of 2-mercapto benzothiazole) Rubber Accelerator
DM-80 2.1 0.6 TMTM-80 (e.g., tetramethyl 0.05 0.1 thiuram
monosulfide) Rubber antioxidant 0.8 (SP; styrenated 0.8 (BHT;
butylated phenol) hydroxytoluene) Process aid 1 (CH236) 5 (SK-120)
Microcrystalline wax 0.5 (P-10) 0 Silica ZC-185 (e.g., IM VN 10 0 3
GR) 1956 0.5 0 PEG 4000 1 0 ST/AC 1 0.8 CaCO.sub.3 60 80
[0047] FIG. 4 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments:
[0048] (420) positioning an uncured rubber tape between a first
footwear component layer and a second footwear component layer such
that the first and second footwear component layers overlap with
the uncured rubber tape positioned therebetween;
[0049] (440) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the uncured rubber tape; and
[0050] (460) at least partially curing the rubber tape.
[0051] FIG. 5 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG. 4,
plus one additional step:
[0052] (410) coupling an uncured rubber tape to a first and/or
second footwear component layer with adhesive;
[0053] (420) positioning the uncured rubber tape between the first
footwear component layer and the second footwear component layer
such that the first and second footwear component layers overlap
with the uncured rubber tape positioned therebetween;
[0054] (440) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the uncured rubber tape; and
[0055] (460) at least partially curing the rubber tape.
[0056] FIG. 6 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG. 5,
plus one additional step:
[0057] (410) coupling an uncured rubber tape to a first and/or
second footwear component layer with adhesive;
[0058] (420) positioning the uncured rubber tape between the first
footwear component layer and the second footwear component layer
such that the first and second footwear component layers overlap
with the uncured rubber tape positioned therebetween;
[0059] (430) stitching the first footwear component to the second
footwear component;
[0060] (440) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the uncured rubber tape; and
[0061] (460) at least partially curing the rubber tape.
[0062] FIG. 7 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG. 6,
plus one additional step:
[0063] (410) coupling an uncured rubber tape to a first and/or
second footwear component layer with adhesive;
[0064] (420) positioning the uncured rubber tape between the first
footwear component layer and the second footwear component layer
such that the first and second footwear component layers overlap
with the uncured rubber tape positioned therebetween;
[0065] (430) stitching the first footwear component to the second
footwear component;
[0066] (440) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the uncured rubber tape;
[0067] (450) heating the footwear to about 70-85.degree. C.;
and
[0068] (460) at least partially curing the rubber tape.
[0069] FIGS. 8A and 8B illustrate an alternate method of forming a
waterproof seam between a footwear upper and a shell outsole,
wherein FIG. 8A illustrates a footwear upper, top welt, and outsole
shell ready for assembly, and FIG. 8B illustrates the footwear
upper, top welt, and outsole shell of FIG. 8A after assembly and
stitching, in accordance with various embodiments. Referring to
FIG. 8A, in the illustrated embodiment, the rubber tape 204 has
been co-extruded with a top-welt 212 to form a co-extruded
top-welt/rubber tape 220. In some embodiments, the co-extruded
top-welt/rubber tape 220 may be partially vulcanized, either prior
to coupling to the shell outsole 210 or after coupling to shell
outsole 210, for instance if it is desirable to reduce the
flowability of the rubber tape 204 of the a co-extruded
top-welt/rubber tape 220.
[0070] In some embodiments, a strip of cement may then be applied
to the outer, upper edge 214 of the shell outsole 210, and the
co-extruded top-welt/rubber tape 220 may be affixed to the outer,
upper edge 214 of the shell outsole 210, leaving the rubber tape
204 sandwiched between the shell outsole 210 and the top-welt
212.
[0071] Referring to FIG. 8B, once the co-extruded top-welt/rubber
tape 220 has been affixed to the shell outsole 210, the footwear
upper 200 may be attached to the shell outsole 210, for example, by
stitching 216 or otherwise forming a seam running through the
footwear upper 200, the co-extruded top-welt/rubber tape 220, and
the shell outsole 210. Once the seam has been formed, additional
heat may be applied to the seam to accelerate curing of the rubber
and/or to assist the rubber tape to flow into empty spaces and
create a waterproof seal. Without being bound by theory, curing of
the rubber tape may allow the rubber tape (and co-extruded
top-welt/rubber tape 220) to be fixed in position, and may prevent
further flowing of the rubber tape.
[0072] In some embodiments, one or more layers of gunking adhesive
(not shown) may be applied to the inside vamp and heel regions of
the leather upper portion of the footwear upper before or after the
final heating. In various embodiments, this gunking adhesive may
include a CR-based adhesive, polyurethane cement, hotmelt adhesive,
CR cement, CR-grafted adhesive, latex adhesive, natural rubber
paste, synthetic rubber paste, or a mixture thereof.
[0073] In particular embodiments, the cement used to couple the
co-extruded top-welt/rubber tape 220 to the shell outsole 210 may
comprise GL-033N/NW cement, although one of skill in the art will
appreciate that many different suitable cements may be substituted.
In some embodiments, a corresponding strip of primer, such as NP11
primer, also may be applied to the rubber tape side of the
co-extruded top-welt/rubber tape 220. Although the method as
disclosed herein describes applying cement to shell outsole 210 and
primer to the rubber tape side of the co-extruded top-welt/rubber
tape 220, one of skill in the art will appreciate that in other
embodiments, primer may be applied to shell outsole 210 and cement
may be applied to the rubber tape side of the co-extruded
top-welt/rubber tape 220. In still other embodiments, cement may be
applied to both components.
[0074] FIGS. 9A-9C illustrate three steps in the alternate method
shown in FIG. 8A, including a close-up view of the rubber tape side
of a co-extruded top-welt/rubber tape (FIG. 9A), a cross-sectional
view of a co-extruded top-welt/rubber tape that has been coupled to
an outsole shell (FIG. 9B), and a cross sectional view of the
top-welt/rubber tape and outsole shell of FIG. 9B after the
footwear upper has been coupled and stitched into place with the
stitching passing through the leather upper, top-welt/rubber tape,
and outsole shell (FIG. 9C), in accordance with various
embodiments. Turning first to FIG. 9A, which shows the rubber tape
side of a co-extruded top-welt/rubber tape 220 shown in FIG. 8A, it
is apparent that in some embodiments the top-welt 212 may extend
beyond the edges of the rubber tape 204.
[0075] As shown in FIG. 9B, the top welt 212 may include a thicker
portion 212a or ledge on one side. In some embodiments, this
thicker portion 212a may extend beyond the lower edge of the upper
in the assembled boot, and may serve as a guide during assembly.
Once the co-extruded top-welt/rubber tape 220 has been coupled to
the shell outsole 210, the rubber tape 204 may be sandwiched
between the top-welt 212 and the outsole 204.
[0076] Turning now to FIG. 9C, in various embodiments, the upper
200 may be coupled or positioned on the top-welt side of
co-extruded top-welt/rubber tape 220, sandwiching the co-extruded
top-welt/rubber tape 220 between the upper 200 and the shell
outsole 210, with the top-welt 212 positioned between the upper 200
and the rubber tape 204. Without being bound by theory, positioning
the top-welt 212 in this fashion may prevent excess rubber tape 204
from passing through the holes created by the stitching 216 and
marring the outside surface of upper 200.
[0077] FIG. 10 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments:
[0078] (1020) positioning a co-extruded top-welt/rubber tape
between a first footwear component layer and a second footwear
component layer such that the first and second footwear component
layers overlap with the uncured rubber tape positioned
therebetween;
[0079] (1040) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the co-extruded top-welt/rubber tape; and
[0080] (1060) at least partially curing the rubber tape.
[0081] FIG. 11 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG.
10, plus one additional step:
[0082] (1010) coupling co-extruded top-welt/rubber tape to a first
and/or second footwear component layer with adhesive, with the
rubber tape side of the co-extruded top-welt/rubber tape facing the
first and/or second footwear component layer;
[0083] (1020) positioning the co-extruded top-welt/rubber tape
between a first footwear component layer and a second footwear
component layer such that the first and second footwear component
layers overlap with co-extruded top-welt/rubber tape positioned
therebetween;
[0084] (1040) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the co-extruded top-welt/rubber tape; and
[0085] (1060) at least partially curing the rubber tape.
[0086] FIG. 12 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG.
11, plus one additional step:
[0087] (1010) coupling co-extruded top-welt/rubber tape to a first
and/or second footwear component layer with adhesive, with the
rubber tape side of the co-extruded top-welt/rubber tape facing the
first and/or second footwear component layer;
[0088] (1020) positioning a co-extruded top-welt/rubber tape
between a first footwear component layer and a second footwear
component layer such that the first and second footwear component
layers overlap with the uncured rubber tape positioned
therebetween;
[0089] (1030) stitching the first footwear component to the second
footwear component;
[0090] (1040) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the co-extruded top-welt/rubber tape; and
[0091] (1060) at least partially curing the rubber tape.
[0092] FIG. 13 is a schematic diagram illustrating a method of
forming a waterproof seam in an article of footwear, in accordance
with various embodiments. The steps include the features of FIG.
12, plus one additional step:
[0093] (1010) coupling co-extruded top-welt/rubber tape to a first
and/or second footwear component layer with adhesive, with the
rubber tape side of the co-extruded top-welt/rubber tape facing the
first and/or second footwear component layer;
[0094] (1020) positioning a co-extruded top-welt/rubber tape
between a first footwear component layer and a second footwear
component layer such that the first and second footwear component
layers overlap with the uncured rubber tape positioned
therebetween;
[0095] (1030) stitching the first footwear component to the second
footwear component;
[0096] (1040) forming a seam between the first footwear component
layer and the second footwear component layer, wherein the seam
passes through the co-extruded top-welt/rubber tape;
[0097] (1050) heating the footwear to about 70-85.degree. C.;
and
[0098] (1060) at least partially curing the rubber tape.
[0099] Although certain embodiments have been illustrated and
described herein, it will be appreciated by those of ordinary skill
in the art that a wide variety of alternate and/or equivalent
embodiments or implementations calculated to achieve the same
purposes may be substituted for the embodiments shown and described
without departing from the scope. Those with skill in the art will
readily appreciate that embodiments may be implemented in a very
wide variety of ways. This application is intended to cover any
adaptations or variations of the embodiments discussed herein.
Therefore, it is manifestly intended that embodiments be limited
only by the claims and the equivalents thereof.
* * * * *