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. 15, 1980
Filed:
Jul. 10, 1975
Teijin Limited, Osaka, JP;
Abstract
A stretch-oriented laminate polyester film consisting of two or three layers of polyester films; both polyester film A and polyester film B which form the external layers of the laminate film are composed of a polyester having an intrinsic viscosity of 0.35 to 1.0, wherein the intrinsic viscosity of a polyester forming the polyester film B is 0.02 to 0.5 greater than that of a polyester forming the polyester film A. The laminate film is curled in the widthwise direction with the polyester film B located inwardly of the curl. This film can be used for various applications, especially as a measuring tape, an adhesive tape and a base of a photographic film. As a preferred embodiment, a laminate polyester magnetic tape with reduced drop-out occurrence, comprising the stretch-oriented laminate film and a magnetic layer coated on one external layer thereof, the polyester film A forming one external layer of the laminate film having incorporated therein a finely-divided inert compound so that its coefficient of static friction becomes not more than 0.80, and the polyester film B forming the other external layer of the laminate film being a film having a coefficient of static friction greater than that of the polyester film A by at least 0.05 and a smoother surface, with the magnetic layer being coated on the surface of the polyester film B is disclosed.