The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 2000
Filed:
Mar. 13, 1998
Siebolt Hettinga, Des Moines, IA (US);
Other;
Abstract
An injection molded bottle closure 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 of forming the injection molded bottle closure comprises forming a mold cavity be engaging a first mold section with a second mold section having a retractable portion, 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.