U.S. patent application number 10/552534 was filed with the patent office on 2006-09-21 for puncture resistant textile structure, especially for shoe soles.
Invention is credited to Roberto Fenzi.
Application Number | 20060211318 10/552534 |
Document ID | / |
Family ID | 33156359 |
Filed Date | 2006-09-21 |
United States Patent
Application |
20060211318 |
Kind Code |
A1 |
Fenzi; Roberto |
September 21, 2006 |
Puncture resistant textile structure, especially for shoe soles
Abstract
A textile structure resistant to perforation, specifically for
shoe soles, comprises one or more layers of woven fabric of
aramidic fibers and one or more layers of woven fabric of high
tenacity non-aramidic fibers; the layers are bonded together by
means of thermoplastic film and each separate layer of fabric is
treated, preferably ably in the right side, by coating with a
polyester and/or acrylic resin enriched with powders of hard and
abrasive materials, such as ceramic materials preferably micronized
and in the form of aluminum silicates.
Inventors: |
Fenzi; Roberto; (Vaiano
(Prato), IT) |
Correspondence
Address: |
PEARNE & GORDON LLP
1801 EAST 9TH STREET
SUITE 1200
CLEVELAND
OH
44114-3108
US
|
Family ID: |
33156359 |
Appl. No.: |
10/552534 |
Filed: |
April 14, 2004 |
PCT Filed: |
April 14, 2004 |
PCT NO: |
PCT/IT04/00208 |
371 Date: |
October 11, 2005 |
Current U.S.
Class: |
442/181 |
Current CPC
Class: |
A43B 13/026 20130101;
A43B 7/32 20130101; A43B 13/12 20130101; F41H 5/0485 20130101; Y10T
442/30 20150401 |
Class at
Publication: |
442/181 |
International
Class: |
D03D 15/00 20060101
D03D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 14, 2003 |
IT |
PO2003A000005 |
Claims
1. Textile structure resistant to perforation, especially for shoe
soles, comprising one or more layers of first fabric woven aramidic
fibers and one or more layers of second fabric high tenacity woven
non-aramidic fibers, said layers being bonded together by means of
thermoplastic film, each individual woven layer being treated,
preferably on the right side, by coating with a resin enriched with
powders of hard and abrasive materials, said resin being a
polyurethane resin or an acrylic resin or a polyurethane and
acrylic resin.
2. Textile structure according to claim 1, wherein said hard and
abrasive materials are ceramic materials, preferably micronized and
in the form of silicates.
3. Textile structure according to claim 2, wherein said micronized
ceramic materials are aluminum silicates.
4. Textile structure according to claim 1, wherein a multilayer
structure includes a first layer of a woven fabric made of aramidic
fibers and, stacked on the first layer, three layers of a woven
fabric made of high tenacity polyester fibers, the layers being
bonded together by means of thermoplastic film and at least one
side of each layer being provided with a surface ceramic
treatment.
5. Textile structure according to claim 4, wherein the layer of
aramidic fabric and the adjacent layer of polyester fabric have the
treated surfaces placed in contact, the remaining layers of
polyester fabric having the treated surface in contact with the
untreated surface of the adjacent layer.
6. Textile structure according to claim 4, wherein not more than
15-20% by weight of the total by weight of the textile fibers used
consists of aramidic fibers.
7. Textile structure according to claim 5, wherein: the fabric in
aramidic fibers is a plain weave fabric having warp yarns in
aramidic fibers, specifically Kevlar.RTM. 730 dtex, 19 yarns per
cm, and weft yarns in aramidic fiber, specifically Kevlar.RTM. 730
dtex, 15 yarns per cm, coated on the right side with 90-120 gr/sq.
mt. of a compound consisting of 50% polyurethane resin, 25% acrylic
resin, 25% aluminum silicate; the fabric in polyester fiber is a
compound weave fabric, made up of two simple weaves 3.times.3, with
the warp and weft yarns in polyester H.T. 1100 dtex, 22 per cm and
29 per cm respectively, and is coated on one side with said
compound.
8. Structure according to claim 7, wherein electrically conductive
wires are inserted in the fabric in aramidic fibers and in the
fabric in high tenacity non-aramidic fibers composing said
multilayer structure.
9. Textile structure according to claim 1, wherein the layers of
fabric in aramidic fibers are individually alternated with those in
high tenacity non-aramidic fibers.
10. Textile structure according to claim 1, wherein two multilayer
structures of fabric are bonded, one consisting of three stacked
layers of a woven fabric in aramidic fibers treated on the surface
with a ceramic coating and the second consisting of three layers of
a woven fabric in high tenacity polyamide fibers treated on the
surface with a ceramic coating.
11. Textile structure according to claim 10, wherein two adjacent
layers of fabric in aramidic fibers or two adjacent layers of
fabric in polyamide fibers, or two adjacent layers of the
multilayer structures have the treated surfaces in contact, the
external surfaces on the top and bottom of the structure being not
treated.
12. Textile structure according to claim 10, wherein not more than
50-60% by weight of the total weight of the textile fibers used
consists of aramidic fibers.
13. Textile structure according to claim 10, wherein: the fabric in
aramidic fibers is a plain weave fabric, having the warp yarns in
aramidic fiber, specifically Kevlar.RTM. 730 dtex, 19 yarns per cm
and weft yarns in aramidic fiber, specifically Kevlar.RTM. 730
dtex, 15 yarns per cm, coated on the right side with 90-120
gr/sq.mt. of a compound consisting of 50% polyurethane resin, 25%
acrylic resin, 25% aluminum silicate; the fabric in polyamide
fibers is a weft rep weave fabric, having warp yarns in high
tenacity polyamide 6:6 fiber, 200 dtex, taslanized, 62 per cm, and
weft yarns in high tenacity Nylon 6:6, 636 dtex, taslanized, 16.5
per cm., coated on the right side with 60 gr/sq.mt. of said
compound.
14. Structure according to claim 1, wherein the thermoplastic films
are made of polyester which resists to high temperatures.
15. (canceled)
16. (canceled)
17. Footwear insole comprising a textile structure according to
claim 1.
18. Footwear comprising a insole according to claim 17.
Description
TECHNICAL FIELD
[0001] This invention concerns a textile structure suitable for use
in footwear, particularly safety footwear, which is required to
have a high level of resistance to penetration by sharp objects
such as nails and the like, especially through the sole.
BACKGROUND ART
[0002] There are known systems of composite structures used for
shoe soles in safety footwear designed to protect the feet from
sharp or pointed objects. Some of these systems use metal plates
which, however, add weight and reduce the flexibility of the shoe.
The high thermal conductivity of the metal plate also makes the
shoes uncomfortable to wear under conditions of high temperature.
In addition, there are further problems when they are worn in
places subject to the surveillance of metal detectors.
[0003] Other systems make use of layers of fabrics made of aramidic
fibers bonded together by a film of thermoplastic polymers (see,
for example Pat. No. US6,368,989). The difficulty with protective
panels of this kind is that they are very expensive, due to the use
of aramidic fibers only.
DISCLOSURE OF INVENTION
[0004] The main object of this invention, therefore, is to provide
a protective textile structure to be used in footwear, particularly
shoe soles, which structure offers high resistance to piercing and
penetration by sharp and pointed objects, while having limited
thickness and weight, adequate flexibility and reduced cost.
[0005] A further object of this invention is to provide a
perforation-resistant textile structure that is also antistatic
and/or resistant to high temperatures.
[0006] These objects are achieved with a perforation-resistant
textile structure in conformity with enclosed claim 1. Advantageous
forms of implementation of the invention are defined in the
dependent claims.
[0007] The advantages and technical characteristics of the
invention will appear clear from the following detailed description
of two non-limiting examples of its implementation.
BRIEF DESCRIPTION OF DRAWINGS
[0008] In the drawings:
[0009] FIG. 1 is a schematic illustration of a first textile
structure in conformity with the invention;
[0010] FIG. 2 shows the polyester fabric used in the structure of
FIG. 1;
[0011] FIG. 3 and 4 illustrate, respectively, the profile of the
warp and weft of the fabric in FIG. 2;
[0012] FIG. 5 is a schematic illustration of a second textile
structure in conformity with the invention.
MODES OF IMPLEMENTATION OF THE INVENTION
[0013] With reference to FIG. 1 and 5, a textile structure 10,10'
resistant to perforation in conformity with the invention basically
consists of a number of layers 12,14,12',14' of woven fabrics
bonded together by means of a thermoplastic film. In particular,
the structure consists of one or more layers 12,12' of woven
aramidic fibers and one or more layers of high tenacity
non-aramidic fibers (for example, polyamide, polyester, polyolefin,
liquid crystal fibers) woven into a fabric structure. Each separate
layer of fabric has, preferably on the right side, a treated
surface 16 coated with a polyurethane and/or acrylic resin
reinforced with powders of hard, abrasive substances, preferably
micronized ceramic materials in the form of silicates, e.g. of
aluminum.
[0014] In the structure, the layers of aramidic fibers can be
individually alternated with layers of fabric in non-aramidic
fibers.
[0015] Two textile structures, as described more in detail
hereafter, have been found to be particularly effective as well as
practical to produce.
[0016] With reference to FIGS. 1 to 4, a first textile structure
resistant to perforation consists of a multilayer structure 10
including a layer 12 of a woven fabric in aramidic fibers and,
stacked on this layer 12, three layers 14 of a woven fabric in high
tenacity polyester fiber. The layers are bonded together by means
of a thermoplastic film. At least one side of each layer has been
provided with a surface ceramic treatment 16.
[0017] Advantageously, the layers of fabric 12,14 are treated on
the right side of the surface, the layer of aramidic fabric 12 and
the adjacent layer 14 of polyester fabric with the treated surface
16 being in contact, the remaining layers of polyester fabric
having the treated surface in contact with the untreated surface of
the adjacent layer. In this way, both outer surfaces of the
multilayer structure 10 are untreated. It is also advantageous to
use the structure described above inside the soles of footwear with
the layer in aramidic fibers on the tread side.
[0018] Thanks to the coating of ceramic material on the individual
layers of fabric, a structure produced in conformity with this
invention has high mechanical resistance to perforation by pointed
metal objects and impedes their progress through the layers of
fabric.
[0019] In addition, this structure is advantageously characterized
by the fact of being composed in a proportion that does not exceed
about 15% by weight--of the total weight of the textile fibers
used--of aramidic fibers, with the remaining part in high tenacity
polyester fibers. This greatly reduces the production costs with
respect to structures consisting entirely of aramidic fibers,
maintaining it on the order of the production costs of structures
consisting of metal plates, over which it has the advantage of
being highly flexible.
[0020] In the practical implementation of a protective structure in
conformity with the invention, it has been found to be particularly
advantageous to select fabrics 12,14 forming the multilayer
structure 10 described above in the following way.
[0021] Fabric in aramidic fibers: [0022] plain weave; [0023] warp
yarns in aramidic fibers, specifically Kevlar.RTM. 730 dtex,
density 19.+-.2% per cm; [0024] weft yarns in aramidic fibers,
specifically Kevlar.RTM. 730 dtex, density 15.+-.2% per cm; [0025]
ceramic surface layer applied by coating with 90/120 gr/sq.mt. of a
compound consisting of 50% polyurethane resin, 25% acrylic resin,
and 25% aluminum silicate.
[0026] The fabric produced in this way has a finished weight of
340/350.+-.5% gr/sq.mt. with a composition by weight of
approximately 80% Kevlar .RTM., 10% polyurethane, 5% acrylic, 5%
aluminum silicate.
[0027] Fabric in polyester fibers: [0028] compound weave
(illustrated in FIGS. 2 to 4), made up of two simple weaves
3.times.3; [0029] warp yarns in high tenacity (H.T.) polyester
fiber 1100 dtex, density 22.+-.2% per cm; [0030] weft yarns in high
tenacity polyester fiber 1100 dtex, density 29.+-.2% per cm; [0031]
ceramic surface layer applied by coating with 90/120 gr/sq.mt.
[0032] The fabric produced in this way has a finished weight of
690/720.+-.5% gr/sq.mt. with a composition by weight of
approximately 86% polyester fibers, 7% polyurethane, 3.5% acrylic,
3.5% aluminum silicate.
[0033] The weaves used make it possible to produce fabrics with
very tightly woven yarns, making their structure highly cohesive to
provide by their very construction a good resistance to
penetration, while maintaining a high degree of flexibility.
[0034] In particular, the compound weave used for the fabric in
polyester fiber has been found to be particularly effective in the
production of the multilayer structure 10.
[0035] The bonding between the layers of fabric is obtained by hot
calandering with the insertion of a thermoplastic film (polyolefin
and/or polyurethane and/or polyester) between the layers of the
structure; processing the combination with heat causes the bonding
by merger of the ceramic material both with the thermoplastic film
and with the surface layer of the adjacent fabric layer so as to
obtain a single unit with a total thickness of not more than 3 mm
and limited weight.
[0036] Advantageously, using thermoplastic film made of polyester
that is resistant to high temperatures, a structure can be obtained
that is particularly suitable for footwear designed to be used in
the presence of high heat sources.
[0037] The textile structure described above has a general
composition of: [0038] aramidic fibers by weight in a percentage of
approximately 12%.; [0039] high tenacity polyester fibers by weight
in a percentage of approximately 73%.; [0040] surface treatment in
ceramic by weight in a percentage of approximately 15%. [0041]
total weight 2435/2555.+-.5% gr/sq.mt.
[0042] Tests carried out on the structure have proven its effective
resistance to a force of at least 1100N exerted by a nail, as
foreseen by standards pr EN ISO 20344, EN 344/92 and EN
12568/98.
[0043] By inserting electrically conductive wires in the fabric of
the aramidic fibers and in the fabrics in non-aramidic fibers
composing the multilayer structure, an antistatic structure is
obtained which can be used in footwear for which this feature is
required.
[0044] In particular, it is advantageous to produce the fabric in
aramidic fibers with: [0045] the warp yarns consisting, every 74
threads, of a first yarn repeated 73 times in Kevlar.RTM. 730 dtex
and a second yarn repeated once in high tenacity polyamide 180 dtex
in two ply twisted with a filament in stainless steel measuring 60
micron in diameter (a composition thus consisting of 82% polyamide
and 18% stainless steel);. [0046] the weft yarns consisting, every
56 wefts, of a first weft repeated 55 times in Kevlar.RTM. 730 dtex
730 and a second weft repeated once in polyamide and steel as
described above.
[0047] The fabric in polyester fiber is in turn preferably produced
with: [0048] 23.+-.2% warp threads per cm consisting, every 24
threads, of a first yarn repeated 23 times in polyester H.T. 1100
dtex and a second thread repeated once in polyester H.T. 1100 dtex
plus a twisted filament of carbon (or steel) 24 dtex (final
composition 95% polyester 5% carbon); [0049] 25.5.+-.2% weft yarns
per cm consisting, every 30 wefts, of a first weft repeated 28
times in polyester H.T. 1100 dtex and a second weft repeated twice
in polyester H.T. and carbon as described above.
[0050] A second example of a textile structure resistant to
perforation in conformity with the invention is schematically
illustrated in FIG. 5.
[0051] In this case the structure 10' includes two bonded
multilayers 120,140, consisting of a first set of three stacked
layers of a woven fabric 12' in aramidic fibers provided with a
surface ceramic treatment 16 and a second set of three stacked
layers of a woven fabric 14' in high tenacity polyamide provided
with a surface ceramic treatment. Advantageously, at least two
adjacent layers 12' of fabric in aramidic fibers or two adjacent
layers of fabric 14' in polyamide fibers or the two adjacent layers
of the multilayer structures 120,140 have the treated surfaces 16
in contact with each other so that both the outer surfaces (top and
bottom) of the structure 10' are not treated.
[0052] In practical implementation, it has been found to be
particularly advantageous to select the fabrics forming the
multilayer structures 120,140 described above in the following
way.
[0053] Fabric in aramidic fibers: as in the first example described
above.
[0054] Fabric in polyamide fibers: [0055] weft rep weave; [0056]
warp yarns in polyamide 6:6 high tenacity fiber, 200 dtex,
taslanized and density 62 per cm; [0057] weft yarns in high
tenacity nylon 6:6, 636 dtex, taslanized and density 16.5 per cm;
[0058] surface layer of ceramic applied by coating of 60 gr/sq.mt.
of the same compound described above.
[0059] The fabric produced in this way has a finished weight of
about 300 gr/sq.mt. with a composition by weight of 80% of
polyamide fibers, 10% polyurethane, 5% acrylic, 5% aluminum
silicate.
[0060] A structure composed of three layers of fabric in aramidic
fibers and three layers of fabric in high tenacity polyamide as
described above, has a general composition of: [0061] aramidic
fibers by weight in a percentage of approximately 38%.; [0062] high
tenacity polyamide fibers by weight in a percentage of
approximately 34%.; [0063] ceramic surface treatment by weight in a
percentage of approximately 18%.; [0064] total weight approximately
2200 gr/sq.mt. the thickness is under 3 mm (after bonding of the
layers by hot calandering and insertion of thermoplastic film).
[0065] A textile structure capable of resisting penetration, as
described in the above examples, is also thermally insulating and
can be used, in the traditional way, as a protective insert into
soles which are applied to footwear by means of sewing or
gluing.
[0066] This structure can also be used advantageously in the
production of footwear the sole of which is directly made on the
upper by injection molding. For example, in Strobel type footwear,
this structure can constitute the insole, which is first sewn onto
the upper after which the sole is injected. It has been
ascertained, in fact, that the effective resistance to perforation
and penetration of a nail, according to the terms of standard EN
344/92, does not prevent sewing the structure onto the upper, using
needles of an appropriate type.
[0067] The invention thus conceived is susceptible to numerous
alterations and variations, all coming within the sphere of the
inventive concept. Also, all the details can be replaced with
technically equivalent elements.
* * * * *