Shock absorbing innersole and method for preparing same
OwnerJames B. Sullivan, Richard B. Foxinventors
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Abstract
A shock-absorbing innersole for use in footwear, which innersole comprises an innersole body composed of a substantially nondeformable elastomeric-type urethane cellular polymer, having a contoured molded heel and arch section and a substantially flat sheet containing a ball and toe section, the innersole having one or more shock-absorbing inserts in the innersole positioned in the heel, ball or both areas of the innersole, the insert composed of a solid elastomeric polymer which has greater shock-absorbing properties and greater surface tack than the elastomeric urethane of the innersole body.
Claims27
In a method of manufacturing a shock-absorbing, molded innersole for insertion in footwear, which method comprises:
- (a) introducing an expandable, polyurethane into a mold;
- and
- (b) recovering from the mold an innersole which comprises a contoured heel and arch section composed of a substantially open-celled polyurethane foam material, the improvement which comprises:
- (i) placing an elastomeric insert material into the mold, the insert material having greater shock-absorbing properties and being less resilient than the molded, open-celled polyurethane foam material, and the insert material having sufficient surface tack to remain in the placed position in the mold on the introduction of the expandable polyurethane material so as to permit the expandable polyurethane material to expand about the insert material without displacement of the insert material;
- and
- (ii) recovering a molded innersole with the insert material having a tacky surface forming a part of the exposed bottom surface of the recovered innersole.
In the method of manufacturing a molded innersole for use in footwear, which method comprises:
- (a) introducing an expandable, reactable, low compression set polyurethane material into a mold cavity;
- (b) introducing a flexible top sheet material into the mold cavity for direct bonding to the expandable polyurethane material and permitting the introduced polyurethane material in the mold cavity to expand and react to form an elastomeric, open-celled polyurethane foam innersole body comprising a heel and arch sectio and a relatively flat ball and toe section, the urethane foam material directly bonded to the flexible top sheet material;
- and
- (c) recovering a full-sole molded innersole, the improvement of which comprises:
- (i) inserting a preformed, solid elastomeric polyurethane insert material into the mold cavity in a position to provide for a shock-absorbing heel or in the ball or both sections of the whole body innersole prior to the introduction of the expandable polyurethane material and the flexible top sheet material, the insert material having greater shock-absorbing properties than the polyurethane foam material and having a greater surface tack than the polyurethane foam material, the surface tack sufficient to permit the insert material to remain in place in the mold cavity on the introduction of the expandable polyurethane material;
- and
- (ii) recovering a molded, full-sole innersole, the insert material having the tacky surface forming an exposed part of the bottom surface of the innersole.
Dependencies are inferred from the claim text.