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:
Jul. 29, 1997
Filed:
Sep. 20, 1995
Yoshihiro Matsukura, Niihari-gun, JP;
Takahisa Ueyama, Niihari-gun, JP;
Kureha Kagaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A spiral die for forming a laminate includes an outer die ring, an inner die ring inserted into the outer die ring with a fit clearance therebetween, a plurality (m, a positive integer greater than 1) of spiral grooves each having a gradually decreasing depth disposed between the outer and inner die rings, and distribution paths for distributively introducing melted resin streams of a plurality (n, a positive integer satisfying n<m) of resin species in a prescribed order into said plurality (m) of spiral grooves. The individual resin streams distributed to the spiral grooves proceed along the spiral grooves to gradually overflow the respective spiral grooves and overlie each other in a prescribed order before the individual resin streams form a uniform tubular stream in a die axial direction.