LIQUID DEVELOPER AND METHOD FOR MANUFACTURING THE LIQUID DEVELOPER

• Main Authors: MASUDA AYANO, NATORI MAKOTO, HASEGAWA WAKA, SHIRAKAWA JUN, ITO JUNJI, AICHI YASUHIRO
• Format: Patent
• Language: English; Japanese
• Published: 25.04.2019
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

To provide a liquid developer that has high volume resistivity of the liquid developer, has toner particles with a small particle diameter in the liquid developer, and is excellent in dispersion stability of the toner particles.SOLUTION: A liquid developer contains a carrier liquid having an SP value of 8.20 or less, toner particles insoluble in the carrier liquid, and a toner particle dispersant, wherein the toner particles contain a polyester resin having an acid value of 5 mgKOH/g or more and 50 mgKOH/g or less; the polyester resin has a number average molecular weight of 3500 or more and 20000 or less; the toner particle dispersant is a polymer having primary amino groups; the polymer having the primary amino groups has an amine value of 30 mgKOH/g or more and 200 mgKOH/g or less; the ratio of the total number of acid radicals in the polyester resin to the total number of amino groups in the polymer having the primary amino groups is 1.0 or more and 10.0 or less.SELECTED DRAWING: None 【課題】液体現像剤の体積抵抗率が高く、液体現像剤中のトナー粒子の粒径が小さく、該トナー粒子の分散安定性に優れた液体現像剤を提供すること。【解決手段】ＳＰ値が８．２０以下であるキャリア液体、該キャリア液体に不溶なトナー粒子、及びトナー粒子分散剤を含有する液体現像剤であって、該トナー粒子が、酸価５ｍｇＫＯＨ／ｇ以上５０ｍｇＫＯＨ／ｇ以下のポリエステル樹脂を含有し、該ポリエステル樹脂の数平均分子量が３５００以上２００００以下であり、該トナー粒子分散剤が、１級アミノ基を有するポリマーであり、該１級アミノ基を有するポリマーのアミン価が３０ｍｇＫＯＨ／ｇ以上２００ｍｇＫＯＨ／ｇ以下であり、該１級アミノ基を有するポリマーのアミノ基の総数に対する、該ポリエステル樹脂の酸基の総数の比が１．０以上１０．０以下であることを特徴とする液体現像剤。【選択図】なし