Yamada Chemical Co., Ltd.

Nagase Chemicals Ltd.

Hajime Kawai

Katsuhiko Tsunemitsu

Yoshiharu Fujino

Seiichi Nieda

Kazuhiko Gendai

Youji Shimizu

Masatoshi Taniguchi

Toshiro Narizuka

Takayuki Kurosaki

Yoji Shimizu

Yasushi Nakai

Hidekazu Ishida

Toshiyuki Nakai

Manabu Yamada

Yutaka Muraki

The present invention provides a novel phthalide compound represented by the following formula, which rapidly forms blue-blue black color with a developer when it is used as a recording material and, since a color image formed therewith has an intense absorption at 700.about.50 nm, it is usable for optical character reader; ##STR1## where R.sup.1 and R.sup.2 represent, independently, alkyl group having 6 or less carbon atoms; cycloalkyl group having 5 or 6 carbon atoms; aryl group; or heterocyclic ring connecting R.sup.1, R.sup.2 and N, R.sup.3 and R.sup.4 represent, independently, alkyl group having 6 or less carbon atoms; cycloalkyl group having 5 or 6 carbon atoms; aryl group; a heterocyclic ring connecting R.sup.3, R.sup.4 and N, X.sup.1 .about.X.sup.3 represent, independently, hydrogen atom, alkyl group having 6 or less carbon atoms, alkoxy group having 6 or less carbon atom or halogen atom, X.sup.4 represents hydrogen atom, alkyl group having 6 or less carbon atoms, alkoxy group having 6 or less carbon atom, halogen atom or ##STR2##

Phthalide compound and recording material using the compound

This invention relates to a thermosensitive recording material containing at least one of durene derivative represented by the formula (I): ##STR1## wherein Z represents CH.sub.2 OX or H, X represents an alkyl group, a cycloalkyl group, a substituted or unsubstituted aralkyl group or aryl group, or --COR group where R represents an alkyl group or a substituted or unsubstituted aryl group, in a recording layer which contains a leuco dye and a color-developing agent which reacts with said dye so as to form a color by heating, and the thermosensitive recording material having high color sensitivity can be obtained.

Thermosensitive recording material

Disclosed herein is a process for producing 3,3-bis-(4-dimethylaminophenyl)-6-dimethylaminophthalide, which process comprises oxidizing 2-[4,4'-bis-(dimethylamino)-benzhydryl]-5-dimethylaminobenzoic acid in an aqueous solution of a mineral acid of pH of from 2.0 to 4.0 with air, oxygen or a gas containing oxygen in the presence of at least one catalyst selected from the group consisting of compounds of iron, copper, cobalt, nickel, chromium, vanadium and manganese.

Process for producing

Disclosed herein are novel divinyl compounds represented by the formula (I): ##STR1## and a recording-material prepared by utilizing the divinyl compounds. The divinyl compound is in itself almost colorless, extremely stable in the atmosphere and develops rapidly blackish color by a developer. The color image given by the divinyl compound is excellent in light-resistance and moisture-resistance and the letters developed can be read by an optical letter-reading apparatus or a barcord reading apparatus.

Divinyl compounds and chromogenic recording-material prepared by using

Disclosed herein is a heat-sensitive recording material in which a chromogenic dye-procursor comprises: (A) a mixture comprising at least two divinyl phthalide compounds represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 represent respectively alkyl group of 1 to 6 carbon atoms, alkyl group of 1 to 4 carbon atoms having an alkoxy group of 1 to 4 carbon atoms or cycloalkyl group of 5 to 7 carbon atoms, X.sup.1 and X.sup.2 represent respectively hydrogen atom, alkyl group of 1 to 8 carbon atoms, alkoxy group of 1 to 8 carbon atoms, alkoxy group of 1 to 4 carbon atoms having an alkoxy group of 1 to 4 carbon atoms, cycloalkoxy group of 5 to 7 carbon atoms, alkenyloxy group of 3 to 8 carbon atoms, benzyloxy group, substituted benzyloxy group, furfurloxy group, tetrahydrofurfuryloxy group, phenyl group, substituted phenyl group, phenoxy group, substituted phenoxy group, fluorine atom, chlorine atom or bromine atom, m and n represent 0 or integer of 1 to 4, m+n=4 and R.sup.1 and R.sup.2 may join together to form a heterocyclic ring, or (B) a mixture of the divinyl phthalide compound(s) represented by the formula (I) and at least one compound selected from the compounds represented by the formulas (II), (III) and (IV): ##STR2## wherein R.sup.3 -R.sup.14 represent alkyl group of 1 to 6 carbon atoms, alkyl group of 1 to 4 carbon atoms each having an alkoxy group of 1 to 4 carbon atoms, cycloalkyl group of 5 to 7 carbon atoms, phenyl group, substituted phenyl group or tetrahydrofurfuryl group, p and q represent 0 or integer of 1 to 4 p+q=4, X.sup.3 represents hydrogen atom, alkyl group of 1 to 4 carbons or chlorine atom, X.sup.4 and X.sup.5 respectively represent hydrogen atom, alkyl group of 1 to 4 carbon atoms, flurine atom, chlorine atom or trifluoromethyl group, R.sup.3 and R.sup.4, R.sup.5 and R.sup.6, R.sup.7 and R.sup.8, R.sup.9 and R.sup.10, R.sup.11 and R.sup.12, and R.sup.13 and R.sup.14 may join together to form heterocyclic rings.

Heat-sensitive recording material

Disclosed herein are novel divinyl compounds represented by the formula (I): ##STR1## and a recording-material prepared by utilizing the divinyl compounds. The present divinyl compound is in itself almost colorless, extremely stable in the atmosphere and develops rapidly blakish color by a developer. The color image given by the present divinyl compound is excellect in light-resistance and moisture-resistance and the letters developed can be read by an optical letter-reading apparatus or a barcord reading apparatus.

Disclosed herein is a chromogenic compound of the formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 respectively represent an alkyl group having 1 to 4 carbon atoms; R.sup.5 represents an alkyl group having 5 to 8 carbon atoms or a cycloalkyl group having 5 to 7 carbon atoms; one of X and Y represents a nitrogen atom and the other of X and Y represents a carbon atom, and a color-forming recording composition containing at least one of the chromogenic compounds.

Chromogenic azaphthalide compound and a colour-forming recording

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.

Chromogenic compounds

Novel chromogenic fluoran compounds of the formula: ##STR1## wherein R.sub.1 is selected from the group consisting of alkyl radicals of from five to eight carbon atoms; R.sub.2 is selected from the group consisting of alkyl radicals of from one to eight carbon atoms; R.sub.3 is selected from the group consisting of hydrogen atom and lower alkyl radicals of from one to four carbon atoms; X.sub.1 and X.sub.2 are independently selected from the group consisting of hydrogen atom and lower alkyl radicals of from one to four carbon atoms, X.sub.3 is selected from the group consisting of hydrogen atom, lower alkyl radicals of from one to four carbon atoms, halogen atoms and trifluoromethyl radical; and n is an integer of a value of 1 or 2; providing that R.sub.1 does not represent an amyl radical when R.sub.2 is selected from the group consisting of alkyl radicals of from one to five carbon atoms, X.sub.1 and X.sub.2 are each a hydrogen atom, X.sub.3 is selected from the group consisting of hydrogen atom, lower alkyl radicals of from one to four carbon atoms and halogen atoms.

Growing community of inventors

Tsuzuki, Japan

Hajime Kawai