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:
Jul. 08, 1997
Filed:
Sep. 20, 1995
Takahisa Oguchi, Mobara, JP;
Hideki Umehara, Yokohama, JP;
Kenichi Sugimoto, Yokohama, JP;
Ryu Oi, Yokohama, JP;
Hisato Itoh, Yokohama, JP;
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Yamamoto Chemicals, Inc., Yao, JP;
Abstract
A phthalocyanine represented by the formula (1) ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently an alkyl group substituted by 0 to 5 halogen atoms and having 1 to 20 carbon atoms, an alkenyl group substituted by 0 to 5 halogen atoms and having 2 to 20 carbon atoms or an alkynyl group substituted by 0 to 5 halogen atoms and having 2 to 20 carbon atoms, and at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is substituted by the halogen atom; X is a halogen atom; each of k, l, m and n is independently a value of from 0 to 3; each of o, p, q and r is independently a value of 0, 1 or 2, and all of them are not 0 simultaneously; each sum of k and o, l and p, m and q, and n and r is independently in the range of from 0 to 4; Met is two hydrogen atoms, a divalent metal atom, a trivalent mono-substituted metal atom, a tetravalent di-substituted metal atom or an oxy-metal atom; an optical recording medium formed by adding this phthalocyanine to a recording layer; and a near infra-red absorbing agent comprising the phthalocyanine. The above-mentioned phthalocyanine can be used to provide the optical recording medium having excellent characteristics of reflectance, sensitivity, recording properties, stability to reproduction light, shelf stability and the like.