Compositions for manufacturing footware stiffeners
AssigneeStanbee Company, Inc.
InventorsDale Martell, Bruce Goldberg, Leo Provencher
Life of this patent
Estimating the term…
Abstract
A microcellular shoe stiffener has at least one adhesive layer coextruded with and carried on a stiffener core. A liquid, such as liquid nitrogen, is introduced into the extruder for the stiffener core to produce a closed cell foam with a gaseous component. The gas reduces the weight and cost of the stiffener with out significantly reducing stiffness and resiliency.
Claims12
A microcellular foam shoe stiffener material, comprising at least one adhesive layer coextruded with and carried on a stiffener core, the stiffener core being made from a polymeric material and nitrogen gas.
A method for manufacturing a microcellular foam shoe stiffener material, comprising:
- extruding a polymeric material from an extruder to form a stiffener core has opposite first and second surfaces;
- extruding first and second adhesive layers onto the first and second surfaces of the stiffener core;
- and
- calendering the first and second adhesive layers onto the first and second surfaces of the stiffener core to produce the stiffener material, wherein
- the step of extruding the polymeric material from the extruder comprises introducing liquid nitrogen into the extruder so that the stiffener core is a closed cell foam that includes a nitrogen gas.
Dependencies are inferred from the claim text.