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:
May. 07, 1991
Filed:
Nov. 28, 1989
Toshiya Mizuno, Tsuchiura, JP;
Yoshikichi Teramoto, Tsuchiura, JP;
Juichi Wakabayashi, Ibaraki, JP;
Takeshi Saito, Tsuchiura, JP;
Kureha Kagaku Kogyo K.K., , JP;
Abstract
A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a poly(arylene sulfide) having a melt viscosity, .eta.* of 1,000-25,000 poises as measured at 310.degree. C. and a shear rate of 200 sec.sup.-1, and a melt crystallization temperature, Tc.sub.2 or 170.degree.-240.degree. C., wherein Tc.sub.2 is an exothermic peak temperature of crystallization which appears upon the measurement by a differential scanning calorimeter at a cooling rate of 10.degree. C./min after the polymer is heated from 23.degree. C. to 380.degree. C. at a rate of 10.degree. C./min and then held for 3 minutes at 380.degree. C. It has a surface roughness, Ra of 0.09 .mu.m or less on at least one side thereof and a degree of crystallization of at least 5%. Its number of flexings to break, Y satisfies the following equation (I):