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:
Feb. 05, 1985
Filed:
Mar. 15, 1984
Noboru Yamato, Tokyo, JP;
Toshimi Satake, Tokyo, JP;
Toshiaki Minami, Tokyo, JP;
Fumio Fujimura, Tokyo, JP;
Jujo Paper Co., Ltd., Tokyo, JP;
Abstract
It has been found that phthalic acid monoester represented by the general formula: ##STR1## in which R is a saturated alkyl group of 4 to 20 carbon atoms where X is an alkyl group, a halogen or an alkoxy group, is applicable as color-developing agent to prepare heat-sensitive recording sheet with excellent results. It is observed that one of the two carboxylic acid groups of which phthalic acid is composed is esterified with the group mentioned in the claim to form water-insoluble, insublimable compound having melting point of 90.degree. to 130.degree. C. wherein the group introduced controls the acidity of the adjacent carboxylic acid group into a condition suitable for stable and concentrated color-development of colorless dye.