A toner for developing an electrostatic latent image is disclosed, which contains as a charge control agent a trivalent chromium salt of salicylic acid or a derivative thereof represented by the following general formula;
1
wherein
R
1
, R
2
and R
3
each represents a hydrogen atom, a saturated or unsaturated, straight or branched alkyl group or, when taken together, R
1
and R
2
or R
2
and R
3
form a fused ring optionally having a saturated or unsaturated, straight or branched alkyl group, and n represents
0, 1
or
2
. The trivalent chromium salts are formed by adding an aqueous solution of alkali metal salt of salicylic acid or a derivative thereof having a pH of
6.5
to less than
7.0
to an aqueous solution of a chromium(III) halide having a pH of
3.0
to
5.8.
本发明揭示了一种用于发展静电潜影像的调色剂,其中包含一种三价
铬盐的电荷控制剂,该三价
铬盐为
水杨酸或其衍
生物的三价
铬盐,其表示为以下通式;
其中,R1、R2和R3分别表示氢原子、饱和或不饱和的直链或支链烷基,或者当它们一起取时,R1和R2或R2和R3形成一个融合环,该融合环可以选择性地具有饱和或不饱和的直链或支链烷基,n表示0、1或2。这些三价
铬盐是通过将
水杨酸或其衍
生物的碱
金属盐的pH为6.5至小于7.0的
水溶液加入pH为3.0至5.8的三价
铬卤化物的
水溶液中形成的。