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:
Aug. 22, 1995
Filed:
Jun. 24, 1994
Kiyoichi Matsumoto, Kyoto, JP;
Shu Tahara, Shiga, JP;
Eiichi Ozeki, Kyoto, JP;
Makoto Ogaito, Kyoto, JP;
Masakazu Kobayashi, Kyoto, JP;
Shimadzu Corporation, , JP;
Abstract
An oriented film with improved tensile strength and Young's modulus can be produced by melting and extruding poly-L-lactic acid and/or poly-D-lactic acid to form a film and, after the film is cooled rapidly, by subjecting it to a stretching process at a temperature above the glass transition temperature and below the cold-crystallization temperature. The stretching may be effected by a method of uniaxial stretching with constant width, successive biaxial stretching or simultaneous biaxial stretching. A thermal treatment may be effected after the stretching process. Films thus obtained have tensile strength over 6 kgf/mm.sup.2 in the stretching direction, Young's modulus over 220 kgf/mm.sup.2 in the stretching direction and transparency to visible light over 90%.