Sakura Color Products Corporation

Kotaro Sumitomo

Hidetoshi Fukuo

Masamitsu Takahashi

Keiko Nakamura

Masamistu Takahashi

The invention provides a crayon which comprises an alternative plasticizer in place of the conventional phthalate ester plasticizers and yet provides writings excellent in water resistance, the crayon comprising a colorant, a gelling agent, an organic solvent, a resin component, and a plasticizer, wherein the plasticizer is at least one selected from diisononyl adipate, acetyltributyl citrate, 1,2-cyclohexanedicarboxylic acid diisononyl, and alkylsulfonic acid phenyl ester and is contained in an amount of 1 to 20% by weight based on the crayon.

Crayon

The invention provides a process for producing a crayon having a desired hardness stably without poor gelation using a benzylidene sorbitol gelling agent together with the use of carbon black as a black pigment. The process comprises:

Crayon and process for producing the same

The invention provides a process for producing a crayon having a desired hardness stably without poor gelation using a benzylidene sorbitol gelling agent together with the use of carbon black as a black pigment. The process comprises: 

The invention provides a process for producing a crayon without poor gelation using a benzylidene sorbitol gelling agent together with the use of carbon black as a black pigment. The process comprises dissolving and dispersing carbon black and a resin component in an organic solvent, dissolving at least one gelling agent selected from the group consisting of dibenzylidene sorbitol, tribenzylidene sorbitol and derivatives thereof in the resultant under heating, pouring the obtained raw material solution into a molding container, and then cooling and solidifying the solution, wherein carbon black having an average particle diameter of primary particles of 20 to 100 nm is used as the carbon black.

Process for production of black crayon

The invention provides a photostorage solid drawing medium comprising a solvent, a resin soluble in the solvent, a photostorage pigment and a gelling agent, wherein the photostorage pigment comprises a long afterglow fluorescent substance comprising an alkaline earth aluminosilicate as a matrix activated with a rare earth element wherein the alkaline earth element is at least one selected from the group consisting of strontium, calcium, magnesium and barium. The solvent used is a polar solvent, particularly a mixture of water and a water-soluble organic solvent, or at least one alcoholic solvent selected from the group consisting of glycols, glycol ethers, glycol ether esters and monovalent alcohols.

Photostorage solid drawing medium

Disclosed herein is a first solid drawing material comprising water, a coloring agent, a solidifying agent that is a fatty acid alkali metal salt, and an O/W type emulsion of a separating agent that is an oily material which hardly volatilizes at room temperature. The first solid drawing material preferably contains silicone oil. A second solid drawing material is also disclosed, which comprises an organic solvent, a coloring agent, a solidifying agent that is at least one selected from the group consisting of dibenzylidene sorbitol, tribenylidene sorbitol, and derivatives thereof, a separating agent that is an oily material which hardly volatilizes at room temperature, and a resin soluble in the organic solvent. In these solid drawing materials, the separating agent is evenly dispersed, and therefore they have stable drawing properties and erasability.

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Sijonawate, Japan

Kotaro Sumitomo