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:
Jan. 13, 1998
Filed:
Sep. 05, 1995
Idemitsu Petrochemical Co., Ltd., Tokyo, JP;
Abstract
A method is provided for producing a thermoplastic resin sheet or film by hot-melting and then cooling a thermoplastic resin to form a sheet or film. The thermoplastic resin sheet or film is moved so that it is pressed against the outer surface of an external heated roll and against a heated, endless metal belt. The endless metal belt is disposed at one end around a moving, internal heating roll and at an opposite end thereof around a moving, internal cooling roll. The internal heating roll heats the endless metal belt to a temperature higher than the softening point of the thermoplastic resin and higher than the temperature of the external heating roll to thermally adhere the thermoplastic resin sheet or film to the external heated roll or the heated, endless metal belt. The thermoplastic resin sheet or film is then moved along on the external heated roll or belt into a high temperature zone. The thermoplastic resin sheet or film is then released from the contact with the external heated roll and released from contact with the endless metal belt in a low temperature zone. The thermoplastic resin sheet or film is then peeled from the endless metal belt. Methods are also provided for producing a laminate of two or more thermoplastic resin sheets or films. The above methods provide non-stretched thermoplastic resin sheets, films or laminates with high-quality surfaces, which are suitable for wrapping foods and medicines.