A liquid electrostatic developer containing negatively chargeable resin particles with improved charging characteristics, said developer consisting essentially of
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,
(B) nonpolar liquid soluble ionic or zwitterionic charge director compound, and
(C) resin particles of a polymer containing at least one acidic constituent having a pKa less than 4.5 preferably 3.0. at 25° in water and an acid number due to said acidic constituent of at least one. The average resin particle size by area is less than l0 µm. Optionally a colorant and other additives or adjuvants are present. The liquid electrostatic developer is useful in copying masking proofs including digital color proofs, lithographic printing plates, and resists.
一种液体静电显影剂,含有可带负电荷的
树脂颗粒,具有更好的充电特性,所述显影剂主要由以下部分组成:(A) 非极性液体,其凯氏
丁醇值小于 30,以大量存在;(B) 非极性液体可溶性离子或齐聚物电荷导向化合物;(C) 聚合物
树脂颗粒,其中含有至少一种酸性成分,在
水中 25° 时 pKa 小于 4.5,最好为 3.0,且所述酸性成分的酸数至少为 1。
树脂颗粒的平均面积尺寸小于 l0 µm,可选择使用
着色剂和其他添加剂或辅助剂。 液体静电显影剂可用于复制遮蔽打样,包括数字彩色打样、平版印刷版和抗蚀剂。