PURPOSE: To prepare the developer useful for making proofs that include copies and digital color proofs and lithographic printing plates and also, forming resists, etc.
CONSTITUTION: This preparation comprises: (A) dispersing a thermoplastic resin in a nonpolar solvent having a Kauri-butanol of <30 at an elevated temp. in a device to form a dispersion; (B) forming a gel or solid lumps from the dispersion without stirring and then crushing the formed product and thereafter subjecting the crushed product to attrition with pulverizing mediums in the device, forming a viscous medium from the dispersion while stirring and subjecting the mixture to attrition with pulverizing mediums, or continuously subjecting the dispersion to attrition with pulverizing mediums in order to inhibit any gel or solid lumps from being formed, to form a dispersion of finer particles and also to cool this dispersion; (C) and the resulting dispersion of toner particles having a <30μm average particle size are separated from the pulverizing mediums; wherein (D) after the stage (A), a mixture of a nonpolar-solvent- soluble, ionic or amphoionic charge control agent compound and an acid is added to the dispersion formed in the stage (A).
JIEIMUZU RODONII RAASON
KASURIN EIMI PAARUSUTAIN
Next Patent: HYDROCARBON-SOLUBLE SULFONIC ACID OR SULFAMIC ACID USED AS CHARGING ASSISTANT FOR POSITIVE ELECTROST...