| 摘要 |
PURPOSE:To obtain a dye having extremely high absorbancy and fastness within a visible region-a near infrared region by adding a specific quinoide type electron acceptive compound, a polyhydric hydroxy aromatic compound and an acidic substance. CONSTITUTION:A quinoid type electron acceptive compound is represented by formula (I) wherein A and B are respectively independently an aryl group and Y is a quinone ring conjugated with two imino nitrogen atoms to form a quinoid structure, for example, a benzoquinone ring, a naphthoquinone ring or an anthraquinone ring). As a polyhydric hydroxy aromatic compound, hydroquinone and a derivative thereof, catechol and a derivative thereof and bisphenol and a derivative thereof are designated. As an acidic substance, both of org. and inorg. compounds can be used. As the org. compound, for example, benzoic acid or naphthoenic acid can be designated and, as the inorg. compound, activated clay, acid clay, kaolin, clay or an acidic resin such as a phenol resin can be designated. The mol ratio of quinoid type electron acceptive compound/ polyhydric hydroxy aromatic compound is pref. 0.05-20. |
