申请人:EASTMAN KODAK COMPANY
公开号:EP0686881A1
公开(公告)日:1995-12-13
A method for making a polymeric particulate, polymeric electrophotographic toner and the particulate and toner. In the method a reaction mixture is prepared that includes vinyl type monomer, crosslinker, and chain transfer agent. The crosslinker has a concentration greater than 0.4 parts by weight per 100 parts by weight of the monomer. The crosslinker and the chain transfer agent together have a combined concentration of greater than 0.6 parts by weight per hundred parts of the monomer. The reaction mixture is subjected to addition polymerization conditions favoring formation of polymer including a first portion having a molecular weight in excess of 1 x 10⁶ and a second, tetrahydrofuran soluble portion having a molecular weight distribution determined by molecular exclusion chromatography including a first peak centered in the molecular weight range of from 0.8 x 10⁴ to 1 x 10⁵. The polymer is melt processed resulting in a melt product, which is then pulverizing to a volume average particle size of from 5 to 20 micrometers to produce particulate. The particulate includes polymer having a molecular weight distribution determined by molecular exclusion chromatography substantially retaining the first peak and including a second peak in the molecular weight range of from 1 x 10⁵ to 1 x 10⁷.
一种制造聚合物微粒、聚合物电子照相调色剂以及微粒和调色剂的方法。该方法制备了一种反应混合物,其中包括乙烯基型单体、交联剂和链转移剂。交联剂的浓度大于每 100 重量份单体 0.4 重量份。交联剂和链转移剂的总浓度大于每 100 份单体 0.6 份(按重量计)。将反应混合物置于有利于形成聚合物的加成聚合条件下,聚合物包括分子量超过 1 x 10⁶的第一部分和可溶于四氢呋喃的第二部分,其分子量分布由分子排阻色谱法确定,包括以 0.8 x 10⁴ 至 1 x 10⁵ 的分子量范围为中心的第一峰。聚合物经熔融加工后得到熔体产品,然后将其粉碎至体积平均粒径为 5 至 20 微米,制成微粒。微粒包括聚合物,其分子量分布通过分子排阻色谱法确定,基本上保留了第一峰,并包括分子量范围在 1 x 10⁵ 至 1 x 10⁷ 之间的第二峰。