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:
Apr. 17, 1990
Filed:
Mar. 03, 1989
Tosoh Corporation, Yamguchi, JP;
Toso Susteel Co., Ltd., Tokyo, JP;
Abstract
In a process for partially curing a powdery polyarylene sulfide resin which comprises heating the powdery resin either in the absence or presence of oxygen while agitating so as to attain an increased melt viscosity in a range suitable for further processing or molding of the resin, an improvement comprising that the resin together with an added specific inorganic additive undergoes the partial curing treatment at temperatures in the range of from a temperature just below the melting point of the starting resin down to a temperature lower by 80.degree. C. than said melting point. The additive is selected from the group consisting of silica, hydrophobic silica, talc and calcium carbonate and mixtures thereof. By use of the additive, the powder characteristics or fluidity properties of the starting resin are substantially retained during and after the partial curing treatment, the static electricity generated by agitation of the resin during the treatment is significantly reduced, and the resin is effectively prevented from forming scaling on the interior walls of the reactor vessel used for the process. Therefore, the agitation of the powdery resin can be uniformly and efficiently effected so that a desired control of the melt viscosity is easily achieved.