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. 12, 2005
Filed:
Feb. 11, 2002
Akinobu Sakamoto, Sodegaura, JP;
Shigehumi Takuno, Ichihara, JP;
Tatsuhiro Nagamatsu, Ichihara, JP;
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
The invention provides, as a method for producing a multi-layer foamed sheet whose scale-like appearance has been improved by means of a multi-layer circular die coextrusion method, a method for producing a multi-layer foamed sheet having foam layers and non-foam layers by a multi-layer circular die coextrusion method which is a method for producing a multi-layer foamed sheet wherein the shear stress at the interface of each layer is 5000 Pa or higher and not higher than 50000 Pa, a method for producing a multi-layer foamed sheet wherein the resin of said non-foam layer is a linear propylenic resin having a melt flow rate of 5 to 30 g/10 minutes, and a method for producing a multi-layer foamed sheet wherein the resin of said foam layer is a propylenic resin whose melt tension (MT) at 190° C. and melt flow rate (MFR) at 230° C. satisfy the following equation A:≧7.52×(−0.576)  [Equation A]