申请人:MITSUBISHI RAYON CO., LTD
公开号:EP0471302A2
公开(公告)日:1992-02-19
A polyester resin for a toner capable of being stably prepared without an occurrence of an abrupt crosslinking reaction is provided. This polyester resin has a crosslinked structure and is derived from (a) at least one member selected from the group consisting of tribasic and tetrabasic carboxylic acid components and trihydric and tetrahydric alcohol components, (b) an aromatic or alicyclic diol component, at least one of the hydroxyl groups of which is a secondary hydroxyl group, (c) optionally other diol component, and (d) a dicarboxylic acid component, wherein the contents of the units of the component (a) and the units of the component (b) satisfy the requirement represented by the following formula (1):
(8m+20n) a - (80m+80n) ≦ b ≦ (8m+20n) a - (12m+30n) (1)
wherein m represents the molar fraction of the tribasic carboxylic acid component and trihydric alcohol component units in the units derived from the component (a), n represent the molar fraction of the tetrabasic carboxylic acid component units and tetrahydric alcohol component units in the units derived from the component (a), the sum of m and n is equal to 1, and a and b represent the molar ratios (mole%) of the units of the component (a) and the units of the component (b) based on the total of the carboxylic acid components, respectively.
本发明提供了一种用于调色剂的聚酯树脂,该树脂可稳定制备而不会发生突然的交联反应。这种聚酯树脂具有交联结构,由以下成分制成:(a) 至少一种选自三元和四元羧酸组分以及三元和四元醇组分组成的组,(b) 芳香族或脂环族二元醇组分、(c) 可选的其他二元醇组分,以及 (d) 二羧酸组分,其中组分 (a) 单元和组分 (b) 单元的含量满足下式 (1) 所表示的要求:
(8m+20n) a - (80m+80n) ≦ b ≦ (8m+20n) a - (12m+30n) (1)
其中,m 表示由组分(a)衍生的单元中三元羧酸组分单元和三元醇组分单元的摩尔分数,n 表示由组分(a)衍生的单元中四元羧酸组分单元和四元醇组分单元的摩尔分数、m 和 n 之和等于 1,a 和 b 分别代表组分(a)和组分(b)的摩尔比(摩尔百分 比),以羧酸组分总量为基准。