To obtain the subject stabilizer having heat resistance while retaining clear hue inherent in organic pigment/dyes.
This stabilizer is represented by formula I (R1 is H, a halogen, a 1-12C alkyl or the like; R2 and R3 are each H, a halogen, a 1-4C alkoxy or the like; D is a coloring matter residue; (n) is 1-2). This stabilizer is obtained by the following procedure: A 2-hydroxyphenylbenzotriazole of formula II is nitrated to obtain a 2-hydroxy-3-nitro-phenylbenzotriazole of formula III and the nitro group of the resultant compound is converted to an amino group to obtain a 2-hydroxy-3-aminophenylbenzotriazole-based compound of formula IV, an ultraviolet-absorbing component. The nitration is performed preferably using 5-40 wt.% nitric acid as a nitration agent, in an inert solvent (e.g. chlorobenzene, dichlorobenzene) and at 30-60°C. The reduction of the compound of formula IV to the corresponding compound of formula I is preferably performed by catalytic hydrogenation.
| JPH11292858 | 2H-BENZOTRIAZOLE DERIVATIVE AND ITS PRODUCTION AND USE |
| JP4246269 | UV-Stabilizer for Siloxane |
UENO JUNPEI
FUKUI KENICHI
