Athletic shoe sole coating for traction enhancement
An athletic shoe coating for traction enhancement includes a pressure sensitive adhesive (PSA) and a tackyfying resin and a film former initially in solution within a solvent suitable for application to the surface of a shoe sole in liquid form, such as by spraying, rolling and brushing the solution onto the shoe sole. After the solvent evaporates a film or coating attaches or is bonded to the shoe sole that exhibits the property of dynamically modifying the traction properties of the shoe sole when pressure and shear forces are applied to the coating. Such modification causes the exterior surface of the film or coating to “refresh” the exposed surface upon impact. This imparts continued tackiness over extended use. Impact modifiers may be added for controlled release of a solvent to temporarily dissolve or soften the film or coating to promote such refreshment of the coating outer surface.
1. A composition for imparting tackiness to a shoe sole surface comprising:
a film former;
an adhesive other than said film former;
a tackifier; and
a solvent capable of dissolving and creating a substantially uniform solution of said film former, adhesive and tackifier suitable for application as a coating to a shoe sole surface, said film former being greater than 65% by weight in a mixture of said film former, adhesive and tackifier after evaporation of said solvent thereby forming a film when applied to a surface and having a liquid-glass transition temperature T g greater than the anticipated use temperatures within the range of 65-110° F. after application to a surface and evaporation of said solvent, the film produced exhibiting a tackiness property only when exposed to shear forces that elevate the temperature of the applied composition at least to the temperature T g , wherein said film former has a softening point above 100° C., said adhesive comprises at least two polymers one polymer having a ball and ring melting point within the range of 70-80° C. and another polymer having a ball and ring melting point within the range of 100°-115° C., and said tackifier comprises a resin having a ball and ring softening temperature within the range of 85°-95° C.
2. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said film former is a polymeric material.
3. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said film former has a “ball and ring” softening point selected to be within a temperature range of 65-125 C.°.
4. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein the shoe sole is made of a predetermined material, and said film former is selected to adhere the composition to said predetermined material.
5. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said adhesive is a pressure sensitive adhesive (PSA).
6. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said at least two polymers are acrylic polymers.
7. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said adhesive is a pressure-sensitive adhesive.
8. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said tackifier is selected from a group consisting of hydrocarbon resins, rosin derivatives, coumarone indene resins, alkylphenolic resins, terpene phenolics, modified alkylphenolic resins, para-tert-butylphenol acetylene copolymer CAS#28514-92-3 and polyterpenes.
9. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said tackifier is prepared from p-tert-octylphenol.
10. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said film former comprises a rosin ester.
11. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said composition comprises, by mass, a solution of greater than 85% solvent, 2-10% film former, and the remaining 2-5% said adhesive and tackifier.
12. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , wherein said solvent is selected from a group consisting of a esters, ethers, ketones, alcohols, natural ester/alcohol mixtures, and aromatic hydrocarbons.
13. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , further comprising nano-sized particles comprising organic emulsion polymerized cross-linked polymers.
14. A composition for imparting tackiness to a shoe sole surface as defined in claim 1 , further comprising nano-sized particles comprising synthetic inorganic clay.
15. A composition as defined in claim 1 , wherein said film former, first and second solid acrylic polymers forming said adhesive and said tackifier are mixed in the respective relative proportions 12.5:0.55:0.71:3.75.
16. A method of increasing selective tackiness to a bottom surface of a shoe sole comprising the step of applying a coating on the surface of the shoe sole; the coating or film being formed by dissolving into a solution a mixture of a film former;
an adhesive other than said film former;
a tackifier; and
a solvent capable of dissolving and creating a substantially uniform solution of said film former, adhesive and tackifier suitable for application as a coating to a shoe sole surface; and
applying a coating of said solution on a surface to evaporate said solvent to create a film, said film former being greater than 65% by weight in a mixture of said film former, adhesive and tackifier after evaporation of said solvent and having a liquid-glass transition temperature T g greater than the anticipated use temperatures within the range of 65-110° F. after application to a surface and evaporation of said solvent, the film produced exhibiting a tackiness property only when exposed to shear forces that elevate the temperature of the applied composition at least to the temperature T g , wherein said film former has a softening point above 100° C., said adhesive comprises a mixture of at least two polymers, one polymer having a ball and ring melting point within the range of 70-80° C. and another polymer has a ball and ring melting point within the range of 100°-115° C. and said tackifier comprises a resin having a ball and ring softening temperature within the range of 85°-95° C.
17. A method as described in claim 16 , further comprising the step of adding, during the dissolving step, nano-sized particles comprising organic emulsion polymerized cross-linked polymer that serve as impact modifiers for selectively softening said composition and rendering said layer tacky.