| 摘要 |
PURPOSE:To improve color forming properties by using an electron donating leuco dye, an electron acceptive compound and 4-chlorobenzyl-4'-ethoxyphenyl ether having an m.p. of predetermined temp. or higher. CONSTITUTION:An electron donating leuco dye, an electron acceptive compound and 4-chlorobenzyl-4'-ethoxyphenyl ether having an m.p. of 89.0 deg.C or higher are used. As the electron donating leuco dye, there are various compounds such as a triphenylmethanephthalide compound or a fluorane compound. As the electron acceptive compound, a phenol derivative or a metal salt of aromatic carboxylic acid is used. The use amount of 4-chlorobenzyl-4'-ethoxyphenyl ether is different according to the kind of a recording material but 0.05 - 2.0g/m<2> generally. The electron donating leuco dye, the electron acceptive compound and 4-chlorobenzyl-4'-ethoxyphenyl ether are ground and dispersed in a dispersing medium until a particle size is reduced to 10mum or less. pref., 3mum or less before use. |
