| 摘要 |
PURPOSE:To obtain a modified pigment improved in long-term dispersibility in vehicle, solvent or the like and not undergoing separation and settling by surface-treating a pigment with a fluorine gas. CONSTITUTION:A pigment (e.g. anthraquinone pigment or titanium oxide) is surface-treated with a fluorine gas to produce a dispersible modified pigment. This treatment is desirably carried out under conditions of a surface treatment temperature of 150 deg.C or below desirably -80 to 50 deg.C and a treatment pressure of 1-760mmHg. Suitable examples of the treating gas include a fluorine gas and a mixture thereof with an inert gas such as nitrogen or argon. When the obtained dispersible modified pigment is mixed with a vehicle, a solvent or the like to form a recording material, a coating material or the like, the obtained product does not undergo pigment agglomeration and settling even after a long-term storage, for example, when used in a ball-point pen, it does not cause plugging and can give a good writing. |
