NEW MATERIAL:A compound of formula I (R1, R1' are 1W4C alkyl, substituted sulfonamide; R2, R2' are amino which may be substituted with acetyl, carbomethoxy, carbethoxy, monomethyl or monoethyl group; X+ is H, Na, K, aliphatic or alicyclic ammonium which may be substituted).
USE: Optically recording agent: it has high resistances to heat and light, high compatibility to resins and high solubility in solvents.
PREPARATION: A compound of formula II such as 2-amino-4-methyl-5-(4'-methylphenylazo)-1-hydroxybenzene is diazotized, coupled with a compound of formula IIIsuch as 1-amino-7-hydroxynaphthalene to give a compound of formula IV. The product is converted into a complex with a chromium donor such as chromium acetate in water or an organic solvent such as ethylene glycol to give the compound of formula I.
NISHII HIROSHI
HINO HIDEOMI
