Cohering and fuse the polymer primary grain after

摘要

PROBLEM TO BE SOLVED: To make it possible to form dignified images having improved fixability and suppress glass of images by specifying the crosslinking degree of primary particles to a specific range with the insoluble component of tetrahydrofuran. SOLUTION: The crosslinking degree of the primary particles of the electrostatic charge image developing toners consisting of coloring particles formed by flocculating and fusing the primary particles of a polymer is specified to 0.01wt.% in the insoluble component of the tetrahydrofura. The toners are formed by associating and fusing plural pieces of the polymer particles having a grain size below the desired toner grain size. The polymer particles are produced by using a known polymn. method. For example, an emulsion polymn. method, suspension polymn. method, soap-free polymn. method, seed polymn. method, molecule dispersion method, two-stage swelling, etc., are used. The method of obtaining the polymer particle dispersion liquid of submicron by using the emulsion polymn. method and associating and fusing plural pieces of such dispersion particles is more preferable.