Sole construction for footwear

Footwear in the form of an athletic shoe including a sole unit, an upper received on said sole unit including a foot receiving opening, and wherein said sole unit includes an outsole, and a midsole located toward said upper and formed by a core of a first plastic material having a characteristic of springiness, and a shell of a second, different, more dense plastic material molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

Footwear in the form of an athletic shoe including a sole unit, an upper received on said sole unit including a foot receiving opening, and wherein said sole unit includes an outsole, a midsole and a heel wedge located on said midsole toward said upper, said wedge formed by a core of a first plastic material having the characteristics of springiness, and a shell of a second different, more dense plastic material having different characteristics molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

For use in footwear having a sole unit including a midsole, a wedge portion adapted to be supported by said midsole within the heel portion of said sole unit, said wedge formed by a core of a first plastic material having a characteristic of springiness, and a shell of a second, different, more dense plastic material molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

For use in footwear, a midsole formed by a core of a first plastic material having a characteristic of springiness, and a shell of a second, different, more dense plastic material molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

For use in footwear, a heel wedge formed by a core of a first plastic material having a characteristic of springiness, and a shell of a second, different, more dense plastic material molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

For use in footwear, a midsole including an integral heel wedge portion, said midsole formed by a core of ethylene-vinyl acetate polymer having a characteristic of springiness, and a shell of polyurethane which is more dense than said core molded about said core to at least substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.

Footwear in the form of an athletic shoe including a sole unit, an upper received on said sole unit including a foot receiving opening, and wherein said sole unit includes an outsole, a midsole and a heel wedge located on said midsole toward said upper, said wedge formed by a core of ethylene-vinyl acetate polymer having a characteristic of springiness and a shell of polyurethane which is more dense than said core molded about said core to substantially encapsulate said core within said shell, and wherein the wall of said shell has a thickness of at least about 0.5 mm.