| 摘要 |
PURPOSE:To improve the stability of a developer against an environmental change such as high temp. and high humidity or low temp. and low humidity by incorporating the pulverous silica powder which is treated with a silicone oil and has a specific degree of hydrophobicity therein. CONSTITUTION:This developer contains the pulverous silica powder of which the surface is treated with the silicone oil. The degree of hydrophobicity of the treated pulverous silica powder is >=90%. The pulverous silica powder is preferably formed by the vapor phase oxidation of the halogen compd. of silicon and is known as dry process silica or fumed silica. The pulverous silica powder is preferably treated with 0.2-70wt% silicone oil and the treatment by the silicone oil is made within an A/10+ or -A/20pts.wt. (A: the specific surface area of the pulverous silica powder) for each 100pts.wt. silica. The high-quality image which maintains the high density even in the environment of high temp. and high humidity or low temp. and low humidity and is free from fogging and scttering to the periphery of the latent image is thus obtd. |
