U.S. patent application number 11/597896 was filed with the patent office on 2008-01-10 for wet grip characteristics of shoes.
Invention is credited to Simon Jeremy Skirrow.
Application Number | 20080005930 11/597896 |
Document ID | / |
Family ID | 35462677 |
Filed Date | 2008-01-10 |
United States Patent
Application |
20080005930 |
Kind Code |
A1 |
Skirrow; Simon Jeremy |
January 10, 2008 |
Wet Grip Characteristics of Shoes
Abstract
Method of improving the performance of sports shoes, especially
soccer boots, by improving the coefficient of friction of key areas
of the shoe (such as the toe box and upper) in both wet and dry
conditions. Described are the application of butylene type
coatings, including polyisobutylene polymers, to maintain desirable
existing characteristics of a shoe, such as feel and feedback, but
which improve grip. Variations such as patches, and areas of
specific types of fabric or coating, are also discussed.
Inventors: |
Skirrow; Simon Jeremy;
(Brisbane, AU) |
Correspondence
Address: |
YOUNG & THOMPSON
745 SOUTH 23RD STREET
2ND FLOOR
ARLINGTON
VA
22202
US
|
Family ID: |
35462677 |
Appl. No.: |
11/597896 |
Filed: |
February 17, 2005 |
PCT Filed: |
February 17, 2005 |
PCT NO: |
PCT/AU05/00229 |
371 Date: |
November 29, 2006 |
Current U.S.
Class: |
36/32R ; 2/159;
36/114; 36/45 |
Current CPC
Class: |
A43B 23/0215 20130101;
A41D 2400/80 20130101; C09J 2489/006 20130101; A41D 19/01564
20130101; A43B 5/025 20130101; D06N 3/106 20130101; C09J 2423/006
20130101; A43D 999/00 20130101; C09D 123/22 20130101; D06N 2211/106
20130101; A43B 1/0072 20130101; A43B 23/0235 20130101; C09J 7/29
20180101; A43B 5/02 20130101 |
Class at
Publication: |
036/032.00R ;
002/159; 036/114; 036/045 |
International
Class: |
A43B 13/14 20060101
A43B013/14 |
Foreign Application Data
Date |
Code |
Application Number |
May 31, 2004 |
AU |
2004902848 |
Claims
1-49. (canceled)
50. A material for use in shoe upper construction which has a PIB
coating comprising a PIB polymer or copolymer, as herein defined,
on its grain or outer face.
51. A material, as claimed in claim 50, which is a leather.
52. A material as claimed in claim 50, in which the PIB coating
comprises a polyisobutylene-isoprene copolymer.
53. A material as claimed in claim 52 in which the percentage of
copolymerised isoprene is within the inclusive weight range of
0.01-5% isoprene
54. A material as claimed in claim 50 in which the PIB polymer has
a Relative Molecular Mass (RMM) in the inclusive range of 600 to
1500.
55. A material as claimed in claim 50, in which the PIB polymer has
a Relative Molecular Mass (RMM) in the inclusive range of 850 to
1200.
56. A material as claimed in claim 50 in which the PIB coating is
applied by a roller coating method.
57. A material as claimed in claim 50 in which the PIB coating
results from the application of a PIB polymer or copolymer in a
solvent mix.
58. A material as claimed in claim 57 in which the solvent
comprises one or more members of the group comprising: paraffins,
mineral oils, benzene, toluene, cyclohexane, xylene, carbon
disulfide, chlorobenzene, hydrocarbons, and halogenated
hydrocarbons.
59. A material as claimed in claim 50 in which the PIB coating
exists in a coverage rate within the inclusive range of 1-70 g/sq.
ft.
60. A material as claimed in claim 50 in which the PIB coating
exists in a coverage rate within the inclusive range of 14-32 g/sq.
ft.
61. A material as claimed in claim 50 whose wet coefficient of
friction, measured by the IUP51 test defined herein, exceeds
3.5.
62. A material as claimed in claim 50 whose dry coefficient of
friction, measured by the IUP51 test defined herein, exceeds
3.5.
63. A process for improving the surface properties of a material,
said process comprising the application of a PIB polymer, or
copolymer coating, thereto to produce the product of claim 50.
64. The material of claim 50 used in the manufacture of uppers for
shoes.
65. The material of claim 50 used in the manufacture of gloves or
apparel.
66. A sports shoe, in which at least part of the upper is
manufactured from a material as claimed in claim 50.
67. A sports shoe as claimed in claim 66 in which the PIB polymer
has an RMM of 850 or greater.
68. A sports shoe as claimed in claim 66 in which the coated
material, is a leather or imitation leather material.
69. A sports shoe as claimed in claim 66 in which treatment with a
said PIB polymer or copolymer is performed either of both of during
or after construction of the upper.
70. A sports shoe as claimed in claim 66 in which the upper
comprises areas both treated and non-treated by said PIB polymer or
copolymer.
71. A sports shoe as claimed in claim 66 in which at least a
portion of the upper comprises a PIB polymer or copolymer coating
which has been applied in a pattern comprising: text, characters,
logos, patterns, or marketing information.
72. A sports shoe as claimed in claim 66 in which the upper also
includes areas of an improved dry grip material as herein
defined.
73. A sports shoe, as claimed in claim 66, which is absent of a
stiffening toe insert, or rubber toe insert.
74. A sports shoe, as claimed in claim 66, which is a soccer
boot.
75. A patch for attachment to a shoe or apparel, comprising a
material as claimed in claim 50.
76. A patch as claimed in claim 75 in which an adhesive material is
applied to the underside, and is overlaid with a protective backing
prior to use.
77. A patch as claimed in claim 75, said patch comprising: an
intermediate substrate; an outer surface coated with a PIB polymer
or copolymer; an underside either having an applied adhesive
coating, or is able to accept an adhesive agent.
78. A patch as claimed in claim 77 in which the intermediate
substrate comprises one or more layers of at least one of: a
fabric, a woven material, a leather, and an artificial leather.
79. A patch as claimed in claim 77 in which the substrate is
flexible.
80. A patch as claimed in claim 77 which is able to stretch in a
least one dimension.
81. A patch as claimed in claim 77 in which the intermediate
substrate is resiliently stretchable in at least one direction.
82. A patch as claimed in claim 77 in which the outer surface has a
coefficient of friction exceeding 3.5 when wet, according to the
IUP51 test defined herein.
Description
FIELD OF INVENTION
[0001] The present invention applies preferentially to sports shoes
and describes methods for increasing the grip of the outer surface
of the shoe upper.
BACKGROUND DESCRIPTION
[0002] A number of factors affect the performance of sports shoes.
Special sets of conditions also exist for different shoe
applications. For instance a cross-trainer will have significantly
different considerations than will shoes manufactured for use in
ball sports--where the shoe may kick and contact the ball. It is
the considerations for shoes manufactured for use in ball sports
with which the present invention primarily concerns itself.
However, this does not preclude the present invention being
subsequently applied for the manufacture of other types of
shoes.
[0003] There are also different sets of considerations affecting
different parts of a shoe, and its manufacture. While these are not
totally independent of each other, the present invention focuses on
the construction of the upper of the shoe. The nature of the upper
affects not only the perceived performance of the shoe during ball
contact, but also influences overall characteristics of the
shoe--for instance, overall rigidity, flexibility, etc. For this
reason, most manufactured shoes for ball sports have followed
fairly traditional techniques--for instance, athletic grade
leathers are the preferred material of construction, despite many
other fabrics and materials being used in the uppers of other types
of sports shoes.
[0004] At least part of the preference for leather relates not just
to overall shoe characteristics, but also the perceived feel and
performance of a shoe by a player. Most of the changes in shoe
upper materials have involved using leathers with different
physical characteristics (e.g. thickness, grain, etc.) or different
types of leathers (e.g. from different animals). Synthetic leathers
tend not to be used in good quality shoes.
[0005] However, while there are a large number of such variables
which manufacturers alter to change the characteristics and
performance of a shoe, there are also significant limitations. One
of these limitations comprises `contact grip`--the degree of grip
between the shoe and a ball when they make contact. This is an
important factor in perceived performance. Where there is good
grip, there is more consistency in both the nature and consequence
of contact. This typically translates to a player improving in
their skills more rapidly as the consistency and predictability of
how a ball reacts (during contact with a ball) allows them to focus
less on compensating for erratic behaviour. Where a ball skids
across the surface of the upper leads to less predictable accuracy
and behaviour, and requires the player to instinctively compensate
based on their own skill and knowledge of the handling
characteristics of the shoe.
[0006] Most existing ball sport shoes (such as soccer boots) from
standard athletic provide reasonably predictable behaviour in the
dry. Even still, grip may not be ideal in all possible contact
situations (with a ball) and less than ideal behaviour results. A
significant proportion of this relates to the degree of grip
between the ball and shoe. Where there is little grip, there is
likely to be skidding, sliding, and other non-wanted interactions
between the ball and shoe. This leads to unwanted behavioral and
perceivable performance problems in a shoe.
[0007] This represents quite a considerable problem. While standard
shoes provide reasonable, but not ideal, performance in the dry,
most games and training sessions are played in wet or damp
conditions. This is where the standard athletic leathers of current
shoes fail significantly. Even where only one contacting surface is
wet, the coefficient of friction falls substantially. In one
standard test--to be described later--the coefficient of friction
of dry athletic leather is 0.8, while wet athletic leather is 0.3.
This provides an indication of the effect of dampness on typical
leathers. Even the coefficient of friction of dry athletic leather
is relatively low, and texturing the leather may only raise this to
about 1.7. Accordingly there are some significant limitations in
the performance of leathers for use in ball sports shoe
construction, and this translates into significant limitations in
the maximum performance of such shoes.
[0008] Accordingly there is a need for a method of improving the
performance, and perceived performance (to a player), of sports
shoes for use in ball sports.
[0009] The inventor is not the only person to recognize the
problems associated with these types of sports shoes. Methods
applied to shoes in the past have focused on texturing processes to
roughen the surface of materials used, or to introduce raised
features which increase water drainage as well as acting as
physical raised surfaces which theoretically grip better. Examples
include the rubber projections of Brutting (U.S. Pat. No.
3,191,321) and the formations of Johnson (U.S. Pat. No. 5,437,112).
Exotic materials such as sharkskin have also been reported
(WO0307745). However, these modifications only provide marginal and
barely acceptable wet grip improvements, and with a cost to
manufacturing ease, cost, and flexibility. Most importantly they
tend to reduce the feedback to a player during ball contact. This
is perhaps one reason why leathers have predominated in the
construction of uppers for sports shoes in ball sports. The
direction that the prior art is heading has thus failed to produce
anything of outstanding or significantly improved quality that
satisfies player's and manufacturer's needs alike.
[0010] Accordingly, there is also a real need for a method for
producing a sports shoe for use in ball sports, which provides
improved grip but not at the expense of reduced player feedback, or
complicated upper manufacturing processes. Ideally a substantially
standard manufacturing process, and production machinery, for
producing leather uppers could be used.
[0011] It is therefore one object of the present invention to
address these considerations.
[0012] It is a further object of the present invention to provide a
shoe having, or means for modifying a shoe to have, improved
gripping characteristics on at least part of the upper when
wet.
[0013] At the very least it is an object of the present invention
to provide the public with a useful alternative choice.
[0014] Aspects of the present invention will be described by way of
example only and with reference to the ensuing description.
GENERAL DESCRIPTION OF THE INVENTION
[0015] According to one aspect of the present invention there is
provided a material for use in shoe upper construction which has a
PIB coating comprising a PIB polymer or copolymer, as herein
defined, on its grain or outer face.
[0016] According to another aspect of the present invention there
is provided a material, substantially as described above, which is
a leather.
[0017] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB coating comprises a polyisobutylene-isoprene copolymer.
[0018] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the percentage of copolymerized isoprene is within the inclusive
weight range of 0.01-5% isoprene
[0019] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB polymer has an RMM in the inclusive range of 600 to
1500.
[0020] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB polymer has an RMM in the inclusive range of 850 to
1200.
[0021] According to another aspect of the present invention there
is provided a material, substantially as described above, which the
PIB coating is applied by a roller coating method.
[0022] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB coating results from the application of a PIB polymer or
copolymer in a solvent mix.
[0023] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the solvent comprises one or more members of the group comprising:
paraffins, mineral oils, benzene, toluene, cyclohexane, xylene,
carbon disulfide, chlorobenzene, hydrocarbons, and halogenated
hydrocarbons.
[0024] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB coating exists in a coverage rate within the inclusive
range of 1-70 g/sq. ft.
[0025] According to another aspect of the present invention there
is provided a material, substantially as described above, in which
the PIB coating exists in a coverage rate within the inclusive
range of 14-32 g/sq. ft.
[0026] According to another aspect of the present invention there
is provided a material, substantially as described above, whose wet
coefficient of friction, measured by the IUP51 test defined herein,
exceeds 3.5.
[0027] According to another aspect of the present invention there
is provided a material, substantially as described above, whose dry
coefficient of friction, measured by the IUP51 test defined herein,
exceeds 3.5.
[0028] According to a further aspect of the present invention there
is provided a process for improving the surface properties of a
material, said process comprising the application of a PIB polymer,
or copolymer coating, thereto.
[0029] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the material is a leather.
[0030] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the material is a bovine, caprine, or kangaroo leather.
[0031] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB coating comprises a polyisobutylene-isoprene copolymer.
[0032] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the percentage of copolymerised isoprene is within the inclusive
weight range of 0.01-5% isoprene
[0033] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB polymer has an RMM in the inclusive range of 600 to
1500.
[0034] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB polymer has an RMM in the inclusive range of 850 to
1200.
[0035] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB coating is applied by a roller coating method.
[0036] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB coating is applied by the application of a PIB polymer or
copolymer in a solvent mix.
[0037] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the solvent comprises one or more members of the group comprising:
paraffins, mineral oils, benzene, toluene, cyclohexane, xylene,
carbon disulfide, chlorobenzene, hydrocarbons, and halogenated
hydrocarbons.
[0038] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB coating exists in a coverage rate within the inclusive
range of 1-70 g/sq. ft.
[0039] According to another aspect of the present invention there
is provided a process, substantially as described above, in which
the PIB coating exists in a coverage rate within the inclusive
range of 14-32 g/sq. ft.
[0040] According to a further aspect of the present invention there
is provided a material having a PIB polymer or copolymer coating,
as herein defined, resulting from a process substantially as
described above.
[0041] According to another aspect of the present invention there
is provided a material, substantially as described above, used in
the manufacture of uppers for shoes.
[0042] According to another aspect of the present invention there
is provided a material, substantially as described above, used in
the manufacture of gloves or apparel.
[0043] According to a further aspect of the present invention there
is provided a sports shoe, in which at least part of the upper is
manufactured from a material substantially as described above.
[0044] According to a further aspect of the present invention there
is provided a patch for attachment to a shoe or apparel, comprising
a material substantially as described above.
[0045] According to another aspect of the present invention there
is provided a patch, substantially as described above, with a
self-adhesive backing.
[0046] According to a further aspect of the present invention there
is provided a sports shoe in which at least part of the upper
comprise gripping areas, in turn comprising a material treated with
a PIB polymer, or copolymer as herein defined.
[0047] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which PIB the polymer has an RMM of 850 or greater.
[0048] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which the coated material, is a leather or imitation leather
material.
[0049] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which treatment with a said PIB polymer or copolymer is performed
during and/or after construction of the upper.
[0050] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which the upper comprises areas both treated and non-treated by
said PIB polymer or copolymer.
[0051] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which at least a portion of the upper comprises a PIB polymer or
copolymer coating which has been applied in a pattern comprising:
text, characters, logos, patterns, or marketing information.
[0052] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, in
which the upper also includes areas of an improved dry grip
material as herein defined.
[0053] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, which
is absent of a stiffening toe insert, or rubber toe insert.
[0054] According to another aspect of the present invention there
is provided a sports shoe, substantially as described above, which
is a soccer boot.
[0055] According to a further aspect of the present invention there
is provided a patch able to be applied to a surface, said patch
comprising: [0056] an intermediate substrate; [0057] an outer
surface coated with a PIB polymer or copolymer; [0058] an underside
either having an applied adhesive coating, or is able to accept an
adhesive agent.
[0059] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which the
intermediate substrate comprises one or more layers of at least one
of: a fabric, a woven material, a leather, and an artificial
leather.
[0060] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which the
substrate is flexible.
[0061] According to another aspect of the present invention there
is provided a patch, substantially as described above, which is
able to stretch in a least one dimension.
[0062] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which the
intermediate substrate is resiliently stretchable in at least one
direction.
[0063] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which the
outer surface has a coefficient of friction exceeding 3.5 when wet,
according to the IUP51 test defined herein.
[0064] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which an
adhesive material is applied to the underside, and is overlaid with
a protective backing prior to use.
[0065] According to another aspect of the present invention there
is provided a patch, substantially as described above, in which the
adhesive material is a non-permanent adhesive.
[0066] According to a further aspect of the present invention there
is provided a shoe to which at least one wet-grip patch,
substantially as described above, is attached.
[0067] The present invention relates in a first instance to
materials, and methods of modifying materials, to improve the
surface properties of their outer surface. Typically, in the
context of the present invention, this means improving the grip or
coefficient of friction, ideally under both wet and dry conditions.
Attaining a comparable coefficient of friction in both wet and dry
conditions is potentially a significant advantage, particularly for
sports and sport shoe manufacture. The materials and processes for
treating a material, will become apparent from the specification,
which for simplicity shall focus on sports shoes and considerations
associated therewith. It should be envisaged however that the
materials of the present invention may also find application other
than for purely sports shoes, and may find application in gloves
and apparel.
[0068] The present invention also relates to a shoe, and
preferentially a sports shoe such as used in ball sports. It has
been discussed that a common problem with typical sports shoes,
such as soccer boots, is that they become slippery and lose grip
when wet. This significantly reduces the accuracy for a player
kicking the ball as the ball can slide, or glance, or spin across
the surface of the boot depending on the exact dynamics of the
impact.
[0069] The present invention introduces means for improving at
least the wet grip characteristics across the entire upper, or part
of the upper, of a shoe. In this context this comprises at the very
least improving the wet grip characteristics relative to standard
leather and imitation leather materials used for sports shoes. The
present invention also provides for the modification of athletic
type leathers, should the user so prefer this material, which are
suitable for use with most manufacturing processes for leather
sports shoe uppers.
[0070] The present invention comprises the application of a
suitable grip enhancing coating to a material from which an upper
is to be constructed, or to a material (such as a patch--see below)
able to be applied to an upper. Preferably the coating process
takes place prior to assembly of the upper, such as the pre-coating
of the material from which the upper is formed. However this does
not preclude coating processes occurring during upper construction,
or after construction of the upper, or coating processes occurring
at different times.
[0071] The present invention makes use of a specific range of
coatings. These preferably comprise Butylene-type coatings, which
include a PIB polymer. A PIB polymer, within the context of this
specification, is a member of the following group: polyisobutylene
(also known as butyl rubber, 2-methyl-1-propene homopolymer,
isobutylene polymer, polymerized 2-methylpropane, isobutylene
resin, and has the molecular formula: [C.sub.4H.sub.8].sub.n), and
polyisobutylene-isoprene copolymers. One specific current products
is product TPC 1105 from Texas Petrochemicals which is a PIB with
an RMM of 1000.
[0072] Typically the butylene-isoprene copolymers will contain
within 0.01-5% isoprene, and nominally 1.+-.0.5% isoprene. These
may be `enhanced` copolymers, in which the isoprene is
substantially homogenously distributed throughout the polymer,
though may also be `highly reactive` copolymers, in which the
isoprene is non-homogenously distributed. The preference of the
two, for use in the present invention, is for using the `enhanced`
copolymers.
[0073] The butylene-isoprene copolymers can also be cross-linked,
and while such cross-linked coatings are within the scope of the
present invention, the preferred option is for substantially
non-crosslinked copolymer coatings.
[0074] For use in the present invention, it is desirable that the
butylene-type coating is readily able to be applied to a substrate
such as leather, though not excluding other materials and fabrics
for use in shoe upper construction. Just as importantly, it should
be able to enhance the coefficient of friction of the substrate,
particularly under wet or damp conditions. As a guideline, some
tests were performed on a range of materials, including one
preferred embodiment of the present invention.
[0075] Ideally the coefficient of friction, when a modified IUP51
test procedure (see below) designated by the International Union of
Leather Technologists and Chemists is used, exceeds a value of 2.0.
More preferably the coefficient of friction should exceed 3.5. In
an ideal material, the coefficient of friction when wet is
approximately the same as, or higher than, the coefficient of
friction when dry. Ideally the coefficient of friction when wet
should also exceed 2.0, and more preferably 3.5 for such a material
or coating. The modified test is based on the standard test using a
PTFE reference bed, but where this is modified to be a leather with
a polyurethane coating as used in soccer ball production.
[0076] By way of example, some representative data for different
materials tested by the inventor follows: TABLE-US-00001 Testing
according to IUP51 of Intl Union of Leather Technologists &
Chemists WET coefficient DRY coefficient Material of friction of
friction Std athletic leather 0.3 0.8 Textured leather 0.8 1.7
Polyisobutylene treated leather 4.7 4.0 Greptile .RTM. G200 3.4 3.5
Rubberised particulate coating 1.5 2.0 Abrasive particulate coating
3.6 3.9 High plasticiser coating of 1.6 11.0 PCT/AU 2004/001545
Silicone rubber coating 1.4 9.8
[0077] This allows a comparison of the preferred polyisobutylene
type material of the present invention with standard materials, and
various dry grip materials developed or utilised by the inventor in
relation to his other inventions--such as defined in PCT/AU
2004/001545.
[0078] As can be seen, the butylene-type coatings of the present
invention, when at least applied to leather, provide a number of
realisable advantages. One is the significantly improved
coefficient of friction for the substrate material in both wet and
dry conditions. The other is the relative consistency of grip in
wet as compared to dry conditions. This consistency is particularly
useful, especially when game and training conditions can change
during their course.
[0079] The inventor has identified a preferred set of
characteristics for butylene-type coatings for use in the
manufacture of shoe uppers. For instance, the optimum RMM (Relative
Molecular Mass) of the PIB polymer is between 600-1500 (inclusive),
though more preferably between 850 and 1200 (inclusive). This is
typically a viscous liquid. Ideally this should have crystal clear
clarity. This latter RMM range, in particular, allows what may be
described as a non-continuous film to be created, allowing a
reservoir of PIB polymer within the internal fibre matrix of the
substrate that will constantly exude to replace worn away/used PIB
polymer on the surface of the leather.
[0080] PIB polymers within the broader RMM range 500-1800
(inclusive) are possible within the present invention, but RMMs at
the limits of this range may not always be ideal. For this reason,
more preferred ranges are identified above. It is desirable to
obtain a draggy, but not sticky, surface. If the surface is too
sticky it will attract too much dust and dirt, which will then
render the surface useless without sufficient cleaning, akin to the
surface of adhesive tape that only works once or twice, e.g. a
clear packaging tape. If a continuous film is engineered of a
softer PIB, then its durability can be limited. By having a
`non-continuous film` there is some realisable advantage.
[0081] An idealised goal is to have a coating which provides
enhanced grip properties, but is also durable and consistent in
performance. Investigations by the inventor have lead to the
preferred PIB polymer characteristics described above.
[0082] The butylene type coating will typically include a solvent,
particularly if a coating process is to be used. The carrier or
solvent used can vary though preferably comprises one or more of:
paraffins, mineral oils, benzene, toluene, cyclohexane, xylene,
carbon disulfide, chlorobenzene, hydrocarbons, halogenated
hydrocarbons, and compatible organic solvents. Paraffin oils offer
less hazard issues than a number of the other solvents, and may be
preferred. However, the coating application process may be enhanced
by the use of more volatile solvents. There is a degree of user
selection and choice available.
[0083] Primers are generally not needed for the application of
butylene type coatings to substrates. However, one should ensure
that the fibre structure is "open enough" to allow easy penetration
into the substrate. If, for instance, the surface is too sealed,
then the PIB polymer will struggle to penetrate deep enough. In
leather, for example, this can be overcome by strong
staking/softening actions in order to break the grain up, though
may wish to be used sparingly for some leathers such as caprine
leathers. Textured leather, where some of the grain has been
removed, roughened, or modified to achieve a permanent surface
design effect, or nubuck or suede leather, are ideal. Leathers that
are highly water repellent or stain resistant can cause slight
impedance of the PIB mixture, and this needs to be taken into
account in the exact formulation of a butylene type coating and its
application process. It is envisaged that some experimentation may
be required for users who wish to optimise a butylene type coating,
or its application process, according to the present invention. It
is considered that this is well within the ability of a skilled
worker given the information of this specification.
[0084] The application of a butylene type coating may be via
different means. For leather, a standard coating machine or
process, e.g. roller-coating, may be considered. For typical sports
shoe construction it is desirable to coat only a single side of the
leather or substrate. Application to both sides may be
uncomfortable, and make it difficult to insert a foot into the
shoe, unless a liner was applied inside the shoe. Double sided
application is also wasteful of coating material, and can increase
manufacturing costs.
[0085] Butylene type coatings may be applied to a substrate from
which an upper is at least partially made, or applied to a semi or
fully constructed upper, or to a completed shoe. It is also
possible that more than one coating may be applied, and that these
coatings may occur at the same or different stages of
manufacture.
[0086] The amount of coating applied can also vary, and may in some
cases be used to alter other physical characteristics of the
substrate. For instance, increasing the amount of introduced PIB
polymer can make leathers feel heavier and more gummy. This may be
desirable for patches (see below) or specific areas on an upper.
Hence, there is a range of user options available to further
improve the utility and usefulness of the present invention.
[0087] Preferably, for athletic leather in sports shoe
construction, we would be likely to see a butylene type coating
process such that the resulting PIB polymer density in the leather
is within the inclusive range of 1-70 g/sq. ft, though more
preferably within the range 14-32 g/sq. ft.
[0088] The coating may be applied substantially continuously across
the substrate. The upper, in such cases, may be manufactured from
different sections of materials possessing different
characteristics--e.g. coated and non-coated sections. However, some
treatment and coating methods can lend themselves to a number of
options. For instance, a sheet of material such as leather (in this
example) could be coated or treated in different manners--e.g.
providing coated and non-coated regions. The different regions may,
should a dye or pigment be included, comprise visual material such
as text, graphics, logos, or other marketing material. Another
variation is patterned regions which enhance performance of the
shoe, or which enhance certain player characteristics. Such
possibilities provide some additional potentially realisable
advantages to both players and shoe manufacturers.
[0089] The use of butylene type coatings on substrates such as
leather can provide other improvement characteristics in shoe
construction. Subjective characteristics important to a typical
soccer player include shoe robustness, form and shape, as well as
compliance factors such as a soft feel and shape. Typically a
rubber toe insert is incorporated to provide some of these
characteristics, but at the expense of some of the other
characteristics and an increase weight. It has been found that the
use of butylene type coated leather provides a shoe with good
subjective qualities but without the need of the toe insert. The
significant weight savings are one advantage for players, while the
absence of an additional component is an advantage for
manufacturers. Hence some aspects of the present invention can
provide additional advantages than just improved grip.
[0090] Another potentially realisable advantage stemming from the
present invention, in relation to leather, is the fact that the PIB
polymer tends to coat the internal fibres of the leather structure.
This renders the fibre quite resistant to the denaturing action of
sweat (more specifically the lactic acid component) which easily
damages leather, and especially de-tans chromium tanned leather and
chromium capped water resistant leathers. Normal attack by lactic
acid will cause hardening of the leather, which in turn reduces
strength, causes actual area shrinkage, allows discoloration, and
offers a suitable environment in which bacteria can grow and
survive. The use of butylene type coating materials of the present
invention on the leather in shoe uppers can avoid these
problems.
[0091] It should be noted that the water resistance of a leather
substrate is improved by coating with a butylene-type coating
according to the present invention. Tests suggest that the water
resistance is improved, on average, by 30%, using static water
uptakes and flexing tests in water (which measure time to penetrate
and the % water absorbed)--e.g. The Maeser Flex Test (as specified
by SATRA--Shoe and Allied Trades Research Association of Kettering
in the United Kingdom--test method STM106/106D). Thus the shoe has
increased water resistance properties, which will ultimately mean
that the shoe will stay lighter throughout a wet game. This is
another potentially realisable advantage of the present
invention.
[0092] Trials have indicated that the tensile and tearing strengths
of leather have been found to improve from treatment with a
butylene type coating. Investigations suggest an improvement of
10-15% is achievable. It is considered that this may be due to the
PIB polymer having a secondary fat-liquoring effect on the leather
fibre structure, which ultimately results in improved internal
fibre matrix lubrication conferring added strength.
[0093] Investigations also indicate an improvement in the
performance of simple textured leathers. This can be explained in
terms of the rationale that a textured leather has improved wet
grip characteristics simply due to the fact that it can reduce
aquaplaning effects by allowing water to sit in the embossed areas
on the surface of the leather--i.e. in the channels between the
peaks and plateaus. However, ignoring the possible deformation of
such peaks and plateaus during ball contact, only the tops of these
peaks and plateaus may actually make ball contact--this is less
than the total surface area. As contact is effectively only being
made on a reduced surface area, the enhanced grip of butylene type
coatings of the present invention will improve the observable grip.
Hence we have an improved grip leather (or material) with drainage
channels for surface water.
[0094] Also within the scope of the invention are patches that may
be applied to shoes to provide certain advantages of the present
invention such as increased wet grip. Typically these patches will
provide a substrate and an outer surface. The outer surface will
have been at least partially coated with a butylene type coating to
provide improved grip characteristics according to what has been
discussed above. Hence the substrate and outer could comprise a
piece of treated leather material, or any of the other material
options.
[0095] The underside may include an adhesive coating. This may be
permanent or non-permanent adhesive, which would allow patches to
be used temporarily or readjusted in position. A removable
protective cover may be provided over the adhesive back.
[0096] The underside may not include adhesive but may be suitable
for the application of an adhesive material. This would allow the
use of different adhesives to be chosen, and might be used on
patches applied during manufacture or by a shoe repairer or other
suitably qualified person. The underside may be absorbent, keyed,
or otherwise modified to improve adhesion.
[0097] Other types of fastening may be provided for attaching the
patch. For instance, hook and pile fasteners, such as Velcro.RTM.,
may be considered.
[0098] As can be appreciated there are many variations to the
present invention, and ways by which it may be implemented. A
specific embodiment will be described, by way of example, next.
DESCRIPTION OF DRAWINGS
[0099] FIG. 1 is a perspective diagrammatic view of one preferred
embodiment of a sports shoe according to the present invention,
and
[0100] FIG. 2 is a perspective diagrammatic view of a preferred
embodiment of a patch according to the present invention.
DESCRIPTION OF PREFERRED EMBODIMENT
Example 1
[0101] A preferred embodiment of the invention is illustrated in
FIG. 1. This embodiment includes a number of possible features of
the invention including wet and dry grip areas.
[0102] FIG. 1 illustrates a soccer boot (1). There is generally
indicated an upper (1a) and a sole (1b). The sole may be of
standard construction for the type of shoe or boot.
[0103] The upper comprises sections of different materials stitched
together, though other methods of construction can be implemented.
For simplicity, we shall refer to common stitched construction in
this example.
[0104] A lower section (2) near the sole comprises a butylene type
coated leather material. Adjacent section (3) comprises a patch of
similar material, which has been adhesively applied to customize
the boot for the player.
[0105] Front section (4) and (5) are a leather material in which a
butylene type coating has been selectively applied in a repeating
pattern comprising the manufacturers logo. Consequently there are
areas of enhanced wet grip distributed over the surfaces of these
sections.
[0106] Sections (6) and (7) comprise dry grip sections of a
material such as Greptile.RTM. G200 which has reasonable wet grip
characteristics as well as dry grip.
[0107] The rear portion (8) may be of various materials according
to user choice. This may be a leather with a textured surface, to
improve grip over normal unmodified leathers.
[0108] It should be noted that this represents just one possible
application of the present invention out of many. Not all sports
shoes need be constructed in this way, nor include as many
different aspects of the invention.
Example 2
[0109] FIG. 2 illustrates a patch (20) according to the present
invention shown partly in cross-section though the dimensions have
been exaggerated. There is provided a substrate (21) of a leather
material treated with a butylene type coating to provide an upper
surface (22) of enhanced wet and dry grip characteristics.
[0110] The underside (23) comprises an adhesive material overlaid
with a removable protective backing (24).
[0111] In practice the patch can be trimmed to shape, if needed,
and adhered to the outer surface of a shoe where required. As
variations, adhesives able to adhere to damp or wet surfaces may be
employed, allowing application to a damp shoe during a game. Also,
pre-contoured patches may be available, which are contoured in
3-dimensions to fit over contoured regions of a shoe such as the
tip of the toe portion.
Example 3
[0112] A typical process to apply a butylene type coating is as
follows: [0113] a. A mix is made of 500 parts TPC1105 from Texas
Petrochemicals, a PIB with an RMM of approximately 1000, and 500
parts Isopar G (Esso), a high purity isoparaffinic solvent with a
boiling point of 41.degree. C. It is noted that the ratio of
PIB:Solvent can be varied to suit the leather/synthetic substrate
being treated or for different end effects. This is typically
determined by the technician applying the material and the final
leather/synthetic required, so as to achieve the desired end
effect. However the 50:50 ratio is a good general formulation.
[0114] b. The mix is agitated constantly to ensure that each
component remains mixed [0115] c. The mix is then applied to the
surface of the material. For leather this may be by any suitable
means--e.g. roller coating--to apply the desired amount of
material. Ideally this is around 12 grams per square foot. [0116]
Synthetic materials may require other equipment for coating
application, e.g. knife over air, etc. Application equipment will
vary. [0117] d. The material, e.g., leather, is then piled with
only coated surfaces touching--commonly known as `facing` in the
tanning industry. If being applied to synthetic leathers then these
will be on a continuous roll production line and will pass
immediately into a heating unit. [0118] e. The material may be
recoated, substantially as described above, or may proceed to final
drying where the last of the solvent is driven off to leave the PIB
polymer in the fibre structure (depending on the substrate) and on
the surface. Some solvent may remain, but this is likely to be
small and evaporate to atmosphere over a short time. The material
will become gripper in nature as the solvent leaves the fibre
structure, due to the relative concentration of PIB polymer
actually increasing. [0119] f. The material is then packed using
suitable means, e.g. grease proof separators, etc for despatch.
[0120] Aspects of the present invention have been described by way
of example only and it should be appreciated that modifications and
additions may be made thereto without departing from the spirit or
scope of the present invention as defined in the appended
claims.
[0121] It should also be understood that the term "comprise" where
used herein is not to be considered to be used in a limiting sense.
Accordingly, `comprise` does not represent nor define an exclusive
set of items, but includes the possibility of other components and
items being added to the list.
[0122] This specification is also based on the understanding of the
inventor regarding the prior art. The prior art description should
not be regarded as being authoritative disclosure on the true state
of the prior art but rather as referencing considerations brought
to the mind and attention of the inventor when developing this
invention.
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