Abstract: A process for producing a baked color pencil lead, comprising dipping a white or pale color porous baked lead having a volume-based median pore diameter of 0.27 &mgr;m or less in a dye ink and then applying a pressure of 1.5 MPa or more thereto to impregnate pores of the above baked lead with the dye ink, in particular, a process for producing a baked color pencil lead, comprising impregnating the pores thereof with a dye ink solution containing as the solvents 35 to 90% by weight of at least one of non-volatile solvents represented by the following Formulas (I) to (III) based on the ink solution and a low boiling organic solvent by applying pressure and then drying the above low boiling organic solvent, and a color pencil lead obtained by the above process: CH3(CH2)7CH═CH(CH2)7CH2OH  (I) R1O(CH2CH2O)nH  (II) in Formula (II), R1 represents decanoyl, undecanoyl, lauroyl, tridecanoyl or oleoyl, and n is 4.

Abstract: A baked color pencil lead prepared by impregnating pores of a white or light-colored porous baked lead with a dye solution prepared by dissolving a dye in a mixed solvent of polyoxyethylene alkyl ether represented by the following Formula (1) and a low boiling point organic solvent, wherein polyoxyethylene alkyl ether contained in the dye solution is adjusted to 35 to 90% by weight, and then drying to remove the low boiling point organic solvent:R.sub.1 --O--(CH.sub.2 CH.sub.2 O).sub.n H (1)wherein R.sub.1 represents a decyl, undecyl, lauryl, tridecyl or oleyl group, and n is an integer of 1 to 14, and a process for producing the same.

Abstract: There are disclosed a solid writing tool which makes it possible to reuse an image holding-supporting member by erasing lines drawn on the image holding-supporting member, and a method of erasing the lines drawn with the above solid writing toll. The solid writing tool contains as a binder 50 to 90 weight % of a thermoplastic resin for toner having a softening point falling within a range of -40.degree. to +60.degree. C. from the temperature of a peeling roller, and 3 to 30 weight % of a lubricant. The drawn line-erasing method comprises dipping an image holding-supporting member on which lines are drawn with the solid writing tool into a peeling liquid containing water, and then erasing the lines by heat and pressure with a peeling roller and a heating roller.

Abstract: By kneading a composition containing a filler and an organic forming binder, extruding the composition, baking the composition in a non-oxidizing atmosphere, there is obtained a first baked lead containing, as a binder, a carbon obtained by the carbonization of the organic forming binder. Then, by heating the first baked lead in an oxidizing atmosphere to remove the binder carbon, there is formed a second baked lead composed of at least the filler. The pores of the second baked lead are impregnated with a solution containing perhydropolysilazane, subjecting the lead to a heat treatment in an inert atmosphere or an ammonia gas atmosphere to form a third baked lead containing the resultant silicon nitride. Finally, ink is filled into the pores of the third baked lead to provide a baked color pencil lead.

Abstract: A baked color pencil lead which can draw lines showing a vivid color and having excellent light fastness while holding excellent physical strength, and which is manufactured by a method comprising the steps of:kneading a blend composition comprising at least a filler and an organic forming binder, molding the composition by extrusion, and baking the molded composition in a non-oxidizing atmosphere, to thereby form a first baked lead containing a binder of a carbon produced by carbonizing the above organic forming binder,heating the first baked lead in an oxidizing atmosphere to remove the binder of the carbon by oxidation, to thereby form a second baked lead,impregnating the pores of the second baked lead with a perhydropolysilazane-containing solution and then subjecting it to a heat treatment in an inert atmosphere such as a nitrogen atmosphere or in an ammonia atmosphere, to thereby form a third baked lead containing silicon nitride produced by the heat treatment, andimpregnating the pores of the third bak