Title:
Wet Grip Characteristics of Shoes
Kind Code:
A1


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)
Application Number:
11/597896
Publication Date:
01/10/2008
Filing Date:
02/17/2005
Primary Class:
Other Classes:
2/159, 36/45, 36/114
International Classes:
A43B13/14; A43B1/14; A43B5/02; A43B23/02
View Patent Images:
Related US Applications:
20020083624Injection molded plastic snowshoeJuly, 2002Lansel
20040016147Hygienic footwear, incorporating material or composites containing silver metalJanuary, 2004Cole
20060026864Ultra-thin liquid-filled insole interfaceFebruary, 2006Arbeiter
20080086910FOOTWEAR WITH REMOVABLE CLOSUREApril, 2008Kim
20030126768Carrier affixed to footwearJuly, 2003Hutt
20080127525Charm attachable to an objectJune, 2008Blunden et al.
20040231196Baby shoeNovember, 2004Kassai et al.
20050198866Shoe tightening systemSeptember, 2005Wiper et al.
20040148809Bicycle shoe soleAugust, 2004Kikuta et al.
20040181975Soft boot for sports useSeptember, 2004Piva
20040078996Footwear with breathable soleApril, 2004Brooks



Primary Examiner:
KRUER, KEVIN R
Attorney, Agent or Firm:
NIXON & VANDERHYE, PC (ARLINGTON, VA, US)
Claims:
1. 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

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

It is therefore one object of the present invention to address these considerations.

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.

At the very least it is an object of the present invention to provide the public with a useful alternative choice.

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

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.

According to another aspect of the present invention there is provided a material, substantially as described above, which is a leather.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

According to another aspect of the present invention there is provided a process, substantially as described above, in which the material is a leather.

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

According to another aspect of the present invention there is provided a patch, substantially as described above, with a self-adhesive backing.

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.

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.

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.

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.

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.

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.

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.

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.

According to another aspect of the present invention there is provided a sports shoe, substantially as described above, which is a soccer boot.

According to a further aspect of the present invention there is provided a patch able to be applied to a surface, 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.

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.

According to another aspect of the present invention there is provided a patch, substantially as described above, in which the substrate is flexible.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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: [C4H8]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.

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.

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.

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.

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.

By way of example, some representative data for different materials tested by the inventor follows:

Testing according to IUP51 of Intl Union
of Leather Technologists & Chemists
WET coefficientDRY coefficient
Materialof frictionof friction
Std athletic leather0.30.8
Textured leather0.81.7
Polyisobutylene treated leather4.74.0
Greptile ® G2003.43.5
Rubberised particulate coating1.52.0
Abrasive particulate coating3.63.9
High plasticiser coating of1.611.0
PCT/AU 2004/001545
Silicone rubber coating1.49.8

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Other types of fastening may be provided for attaching the patch. For instance, hook and pile fasteners, such as Velcro®, may be considered.

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

FIG. 1 is a perspective diagrammatic view of one preferred embodiment of a sports shoe according to the present invention, and

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

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.

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.

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.

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.

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.

Sections (6) and (7) comprise dry grip sections of a material such as Greptile® G200 which has reasonable wet grip characteristics as well as dry grip.

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.

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

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.

The underside (23) comprises an adhesive material overlaid with a removable protective backing (24).

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

A typical process to apply a butylene type coating is as follows:

    • 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° 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.
    • b. The mix is agitated constantly to ensure that each component remains mixed
    • 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.
      • Synthetic materials may require other equipment for coating application, e.g. knife over air, etc. Application equipment will vary.
    • 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.
    • 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.
    • f. The material is then packed using suitable means, e.g. grease proof separators, etc for despatch.

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.

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.

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.