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:
Dec. 22, 1981
Filed:
Nov. 16, 1979
Akiho Ota, Funabashi, JP;
Fumio Negishi, Tokyo, JP;
Yoshino Kogyosho Co., Ltd., Tokyo, JP;
Abstract
Formation of an optical design pattern in an article of polyethylene terephthalate by utilizing the property of polyethylene terephthalate to become crystallized and whitened upon slow cooling and the fact that cooling of a plastic article molded within a mold advances from the surface portion of the article in contact with the surface of the mold toward the wall of the article. Based on this theory, a desired portion of the wall of an article of polyethylene terephthalate is whitened by properly controlling the degree and speed of cooling of the polyethylene terephthalate article in the mold to cool it slowly. The whitened portion in the wall is developed as an optical design pattern that can be viewed from outside. The whitened optical design pattern developed by the aforesaid technique can be made more distinct by heat treatment and stretching treatment.