US 2014/0275306 A1 · ARTICLE WITH CONTROLLED CUSHIONING

Abstract

Pellets, beads, particles, or other pieces of a thermoplastic elastomer having a maximum size in at least one dimension of 10 mm or less (collectively, “pellets”) are infused with a supercritical fluid in a pressurized container, then rapidly depressurized and heated either by immersion in a heated fluid or with infrared or microwave radiation to foam the pellets The pellets are prepared with at least two different densities. Pellets with different densities, thermoplastic elastomer compositions, or foam response rates are placed in different areas of a mold. The mold is filled with pellets, then the pellets are molded into a part. The part has areas of different density as a result of the placement of pellets of different density.

Claims17

Dependent claims

A method of forming a molded article of a thermoplastic elastomer having areas of different density, comprising

(a) preparing pellets of a thermoplastic elastomer having a first density by infusing the pellets with a supercritical fluid, removing the pellets from the supercritical fluid and foaming the pellets by one of (i) immersing the pellets in a heated fluid or (ii) irradiating the pellets with infrared or microwave radiation or (iii) exposing the pellets to a hot gas to make foamed pellets of a first density;
(b) preparing pellets of the thermoplastic elastomer having a second density by infusing the pellets with a supercritical fluid, removing the pellets from the supercritical fluid and foaming the pellets by one of (i) immersing the pellets in a heated fluid or (ii) irradiating the pellets with infrared or microwave radiation or (iii) exposing the pellets to a hot gas to make foamed pellets of a second density;
(c) placing pellets having the first density in a first area of a mold and placing pellets having the second density in a second area of the mold and molding the pellets to form the molded article.

Dependencies are inferred from the claim text.

Article with controlled cushioning

Life of this patent

Article with controlled cushioning

Life of this patent

Abstract

Claims17