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. 19, 1996
Filed:
Aug. 07, 1995
Kazumi Tanaka, Niigata, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
There are disclosed a method for drying and a method for solid-phase polymerizing a crystallizable polyamide being in an amorphous state which comprises regulating the moisture concentration in the polyamide at its glass transition temperature to at least 0.15% by weight as determined by Karl Fisher titration; heating the polyamide thus regulated at a pressure of at least one arm without reducing the moisture to crystallize the same up to a crystallinity of at least 15% and; further heating the polyamide thus crystallized at a temperature lower than its melting point under reduced pressure with a batchwise heating apparatus. It is made possible according to the method for drying or the method for solid-phase polymerizing the crystallizable polyamide to effect its crystallization without causing tackified sticking or solidified sticking of the polyamide, along with drying or solid-phase polymerization with single apparatus and process, while dispensing with any pretreatment such as surface modification and preliminary treatment equipment intended for crystallization.