1. Aryl hydrazides of the formula:
where
X is SO₂ or CO,
R¹ and R² (which may be the same or different) each represents an aliphatic group of at least 2 carbon atoms, a cycloaliphatic group, a substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group;
R³ represents -(CH₂-)n- where n is an integer of 1 to 4, preferably 1 or 2,
R⁴ represents a substituted or unsubstituted aliphatic or a substituted or unsubstituted aromatic group,
R⁵ represents hydrogen or an aliphatic, aromatic or heterocyclic group any of which groups being substituted or unsubstituted, provided that when X is SO₂, R⁵ is not hydrogen, and
Ar represents an aromatic group which may contain alkyl or alkoxy groups in addition to those substituents shown,
are effective nucleators for high contrast photographic silver halide materials.
1.式中的芳基酰
肼:
其中
X 是 SO₂ 或 CO、
R¹ 和 R²(可以相同或不同)各自代表至少 2 个碳原子的脂肪族基团、环脂族基团、取代或未取代的芳香族基团或取代或未取代的杂环族基团;
R³ 代表-(CH₂-)n-,其中 n 是 1 至 4 的整数,优选 1 或 2、
R⁴ 代表取代或未取代的脂肪族或取代或未取代的芳香族基团、
R⁵ 代表氢或任何取代或未取代的脂肪族、芳香族或杂环基团,但当 X 为 SO₂ 时,R⁵ 不是氢,以及
Ar 代表芳香基团,除所示取代基外,还可能含有烷基或烷氧基、
是高对比度照相卤化
银材料的有效成核剂。