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:
Nov. 22, 1988
Filed:
Apr. 21, 1986
Akira Sano, Kawasaki, JP;
Masataka Oka, Fujisawa, JP;
Tetsujirou Kuroishi, Chiba, JP;
Kazuo Matsuura, Tokyo, JP;
Nippon Oil Co., Ltd., Tokyo, JP;
Abstract
A molding composition is disclosed which comprises ultrahigh molecular weight polyethylene having an intrinsic viscosity of 10-30 dl/g at 135.degree. C. in decalin. Improved injection moldability is provided by the use of such polyethylene obtainable by a multi-stage polymerization reaction including at least the following two stages: (a) a first stage in which ethylene is polymerized using a specified composite catalyst in the absence of hydrogen of its presence at lower concentration to produce 50-99.5 weight parts of polyethylene having an intrinsic viscosity of 12-32 dl/g at 135.degree. C. in decalin; and (b) a second stage in which a fresh feed of ethylene is polymerized in the presence of hydrogen at higher concentration to produce 50-0.5 weight parts of polyethylene having an intrinsic viscosity of 0.1-5 dl/g at 135.degree. C. in decalin.