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:
Oct. 07, 1980
Filed:
Feb. 02, 1979
Kanzaki Paper Manufacturing Co., Ltd., Tokyo, JP;
Abstract
The black color developing heat-sensitive recording material comprises a base sheet and a color developing layer formed on at least one surface of the base sheet, the color developing layer including colorless or light-colored chromogenic material and acceptor which is reactive with said chromogenic material to develop a black color. At least 60% by weight of the chromogenic material comprises at least two kinds of black color developing fluoran compounds having the eneral formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, X.sub.l and Ym are described hereinafter and the amount of each of said black color developing fluoran compounds is not larger than 90% by weight of the total amount of said black color developing fluoran compounds.