Method of injection molding an article with a cellular density distribution which gradually varies between a high density cellular exterior and a low density cellular interior

摘要

A method for producing an injection molded article with a gradually varying cellular density distribution, whereby the cellular density distribution varies between a first cellular structure of a high density and a second cellular structure of a relatively lower density. The method comprises forming a mold cavity be engaging a first mold section with a second mold section and injecting into the mold cavity an injection mixture which contains a blowing agent. A gradually varying density distribution is created according to a predetermined control function which depends on the mold cavity volume and the injection rate of the injection mixture.