Toyo Ink Manufacturing Company

Makoto Sakamoto

Tadashi Ogawa

Takeshi Sato

Shuichi Kimura

Michiko Tamano

Hiromitsu Katsura

Motohiko Kashioka

Shigeyuki Ehashi

Shuji Miyazaki

Motonori Ando

Optical recording material and optical recording medium

An optical recording medium which has physical and chemical stability, has high sensitivity to laser light and permits accurate recording and highly reliable reproduction. The medium comprises a transparent substrate and a recording layer formed on the substrate, the recording layer being formed of an organic thin layer containing at least one of phthalocyanine compounds of the formula [1].

Optical recording medium

An optical recording medium which comprises an organic thin film layer containing at least one of phthalocyanine compounds, due to which high light absorptivity to laser beams and high recording sensitivity can be obtained. The optical recording medium provided by the present invention has high chemical and physical stability. There is also disclosed a process for the production of the optical recording medium.

Optical recording medium and process for the production thereof

A pigment composition consisting of 100 parts by weight of a pigment, and from 0.1 to 30 parts by weight of a pigment dispersant of formula ##STR1## in which Q is (a) an anthraquinone dye or pigment radical, (b) an azo dye or pigment radical, (c) a benzimidazolone dye or pigment radical, (d) a phthalocyanine dye or pigment radical, (e) a quinacridone dye or pigment radical, (f) a dioxazine dye or pigment radical, (g) an anthrapyrimidine dye or pigment radical, (h) an anthanthrone dye or pigment radical, (i) an indanthrone dye or pigment radical, (j) a falvanthrone dye or pigment radical, (k) a pyranthrone dye or pigment radical, (l) a perinone dye or pigment radical, (m) a perylene dye or pigment or (n) a thioindigo dye or pigment radical; X is a direct bonds, --CH.sub.2 --; ##STR2## Y.sub.1 is NH or --O--; Z is in which Y.sub.2 is --NH-- or --O--, or --NH--X--Q when n is 1; R.sub.1 and R.sub.2 are independently an alkyl group containing 1-18 carbon atoms, or are jointly combined to form a piperidine, pyrrolidine, pipecoline or morpholine ring with the nitrogen atom to which they are attached; m is an integer of 1 to 6; and n is an integer of 1 to 4. The pigment compositions exhibit improved fluidity, superior stability and gloss.

Pigment composition

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Tokyo, Japan

Makoto Sakamoto