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:
Jan. 14, 1986
Filed:
Jun. 16, 1982
Applicant:
Inventors:
Yoshiharu Fujino, Tsuzuki, JP;
Hajime Kawai, Tsuzuki, JP;
Yasushi Nakai, Kyoto, JP;
Katsuhiko Tsunemitsu, Kyoto, JP;
Assignee:
Yamada Chemical Co., Ltd., Kyoto, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
546116 ;
Abstract
The chromogenic azaphthalide compounds of the invention are of the formula: ##STR1## wherein A is a pyridine ring; R.sub.1 is hydrogen atom or alkyl radicals of from one to 4 carbon atoms; X is hydrogen atom, alkyl radicals of from one to 2 carbon atoms or alkoxy radicals of from one to 2 carbon atoms; R.sub.2 is alkyl radicals of from one to 2 carbon atoms or phenyl radical; R.sub.3 is hydrogen atom or alkyl radicals of from one to 8 carbon atoms. These compounds are particularly suitable for use in providing high quality pressure- or heat-sensitive copying sheets.