Daio Paper Corporation

Showa Highpolymer Co., Ltd.

Taio Paper Manufacturing Co., Ltd.

Yasunori Shimada

Yukio Doi

Koichi Inoshita

Motokazu Aono

Haruo Hattori

Hisashi Yamamoto

Shozo Yoshida

Toshiaki Kawanabe

Michio Kawamura

Mamoru Awano

Hiroshige Teraji

A heat-sensitive recording medium comprising, on a support, a heat-sensitive color-developing layer containing a colorless or light-colored leuco dye (or an electron-donating dye precursor) and a color-developing agent (or an electron-accepting substance) reacting with the leuco dye to develop color as main constituents, said leuco dye being a compound represented by the formula (I): ##STR1## wherein X represents CH.sub.3 --(CH.sub.2).sub.3 --CH.sub.2 or CH.sub.3 --CH.sub.2 --CH.sub.2 and Y represents CH.sub.3 --(CH.sub.2).sub.3 --Ch.sub.2 or CH.sub.3, and said heat-sensitive color-developing layer containing at least one of the compounds represented by the general formula (II) and (III): ##STR2## where R.sub.1, R.sub.1 ' are respectively any one of H, Cl, and CH.sub.3, and may be the same with or different from each other: ##STR3## where R.sub.2, R.sub.2 ' are respectively any one of H and CH.sub.3, and may be the same with or different from each other.

Heat-sensitive recording medium

An improved in-situ polymerization method is provided for easily producing a good slurry of strong, dense, water-resistant and anti-hygroscopic microcapsules made of an amino resin of either of melamine-formaldehyde series or the ureaformaldehyde series, in a high concentration of microcapsules, and a low viscosity.

Method of producing a slurry of microcapsules

Growing community of inventors

Iyomishima, Japan

Yasunori Shimada