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:
Dec. 27, 1988
Filed:
Jul. 14, 1987
Yutaka Ohnishi, Urawa, JP;
Shinji Yoshinaka, Iwatsuki, JP;
Toshiyuki Tanaka, Inagi, JP;
Minoru Koguchi, Ageo, JP;
Takeo Obitsu, Omiya, JP;
Shin Nisso Kako Co., Ltd., , JP;
Abstract
Spirobenzanthracene phthalide compounds are disclosed of the formula (I) ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 independently represent C.sub.1 -C.sub.8 alkyl optionally substituted by C.sub.1 -C.sub.5 alkoxy; C.sub.5 or C.sub.6 cycloalkyl; or aralkyl or aryl optionally substituted by C.sub.1 -C.sub.5 alkyl or C.sub.1 -C.sub.5 alkoxy, and R.sup.1 and R.sup.2, R.sup.3 and R.sup.4, and R.sup.5 and R.sup.6 taken together with the nitrogen atom to which they are attached, may form pyrrolidino, piperidino or morpholino ring, and R.sup.7, R.sup.8, R.sup.9 and R.sup.10 independently represent hydrogen, C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.5 alkoxy or trifluoromethyl. The compounds are used, together with a developer, in color for materials such as pressure-sensitive copying papers, heat-sensitive recording papers and the like.