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. 18, 1987
Filed:
Oct. 14, 1986
Takeo Obitsu, Ohmiya, JP;
Tetsuo Igaki, Kawagoe, JP;
Kimiaki Kinoshita, Kitamoto, JP;
Morio Nanbu, Fujimi, JP;
Shinichi Satoh, Tokyo, JP;
Shin Nisso Kako Co., Ltd., , JP;
Abstract
The fluoran compounds of the formula (I) are new red color forming chromogenic dyes. ##STR1## wherein R represents an isobutyl or isopentyl group, R.sub.1 represents a hydrogen or halogen atom or an alkyl group, R.sub.2 represents a hydrogen or halogen atom or an alkyl group, R.sub.3 represents a hydrogen atom, and R.sub.4 represents a hydrogen atom, or R.sub.4 and R.sub.1 as well as R.sub.2 and R.sub.3 taken together with the carbon atoms to which they are attached may form a benzene ring which may be substituted with a halogen atom. They are used, together with an acidic developer, in chromogenic recording materials for use in pressure sensitive copying paper, heat-sensitive recording paper and thermo-sensitive, reversible color changing composition.