| 摘要 |
1,200,266. Monoazo pigments; lithographic varnishes. AMERICAN CYANAMID CO. 26 April, 1968 [24 May, 1967], No. 19993/68. Headings C4A and C4P. The invention comprises monoazo pigments of formula wherein M is a Ca, Sr or Ba cation. The maroon pigments are prepared by reacting the monoazo dye 2 - naphthylamine - 1 - methylsulphonic acid # 2 - hydroxy - naphthoic acid with an aqueous solution of a Ca, Sr or Ba salt. The pigments wherein the 2-hydroxynaphthoic acid is replaced by 2-naphthol or wherein the Mn cation is present are also described for comparative purposes. In Example 15 the pigments defined above are admixed with lithographic varnish and a cobalt drier and the pigment paste so obtained, mixed with zinc oxide paste to prepare tints for comparison. |
