Baked color pencil lead and method of manufacturing the same
AssigneeMitsubishi Pencil Company, Limited
InventorsMasaaki Hoshiba, Kazutaka Aoki
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AssigneeMitsubishi Pencil Company, Limited
InventorsMasaaki Hoshiba, Kazutaka Aoki
Estimating the term…
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, and impregnating the pores of the third baked lead with an organic pigment solution and solidifying the organic pigment in the pores to allow at least the organic pigment to be contained in the baked lead as a colorant.
A baked color pencil lead manufactured by a method comprising the steps of:
A method of manufacturing a baked color pencil lead, comprising the steps of:
Dependencies are inferred from the claim text.