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. 01, 1991
Filed:
Aug. 16, 1989
Kiyotaka Iiyama, Mishima, JP;
Kunio Hayakawa, Gotemba, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
Coloring phthalide compounds having general formula [I], a method of producing the phthalide compounds and a recording material comprising as a coloring component any of the coloring phthalide compounds, are disclosed, ##STR1## wherein R.sup.1 and R.sup.2 each represent a straight chain or branched alkyl group having 1 to 6 carbon atoms, a cycloalkyl group, or a benzyl group, and R.sup.1 and R.sup.2 in combination may form a ring; R.sup.3 represents and alkyl group having 1 to 4 carbon atoms; R.sup.4 represents a dialkylamino group having 1 to 6 carbon atoms, a cyclic amino group or halogen; l is an integer of 0 to 4; A represents ##STR2## wherein R.sup.5 and R.sup.6 each represent a straight chain or branched alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, or a benzyl group, R.sup.5 and R.sup.6 in combination may form a ring; and B is the same as A, or represents a phenyl group which may have a substituent.