Abstract: An ink composition comprising at least one dye represented by one of the following chemical structural formulae and an anthraquinone-based pigment as coloring materials, an alcohol or an ether as a solvent, and a resin. In a preferred embodiment, a triarylmethane-based dye is used in combination or polyvinylbutyral is contained as the resin. wherein A is a tertiary or quaternary ammonium ion group.

Abstract: An ink composition comprising at least one triarylmethane-based dye as a coloring material, an alcohol having 2 or more carbon atoms, a polyhydric alcohol or a glycol ether as a solvent, and a resin which can dissolve in the solvent, the triarylmethane-based dye comprising a compound represented by the following formula: [C(—Ar—Y)3]A wherein each Ar is independently an aryl group substituted, or not substituted, by a halogen or an alkyl group, each Y is independently a diethylamino group or hydrogen, provided that at least two Y are a diethylamino group, A is a halogen or an organic acid group, and A is charge-balanced to the residue.

Abstract: An ink composition comprising at least one dye represented by one of the following chemical structural formulae and an anthraquinone-based pigment as coloring materials, an alcohol or an ether as a solvent, and a resin. In a preferred embodiment, a triarylmethane-based dye is used in combination or polyvinylbutyral is contained as the resin.

Abstract: An ink composition comprising at least one triarylmethane-based dye as a coloring material, an alcohol having 2 or more carbon atoms, a polyhydric alcohol or a glycol ether as a solvent, and a resin which can dissolve in the solvent, the triarylmethane-based dye comprising a compound represented by the following formula: [C(—Ar—Y)3]A wherein each Ar is independently an aryl group substituted, or not substituted, by a halogen or an alkyl group, each Y is independently a diethylamino group or hydrogen, provided that at least two Y are a diethylamino group, A is a halogen or an organic acid group, and A is charge-balanced to the residue.

Abstract: An ink follower composition for oil-based ballpoint pens, comprising at least one organic solvent selected from the group consisting of a sparingly volatile organic solvent and a non-volatile organic solvent, a gelling agent comprising inorganic fine particles, and from 10 to 60% by weight of a resin soluble in the organic solvent used.

Abstract: An ink follower composition for oil-based ballpoint pens, comprising at least one organic solvent selected from the group consisting of a sparingly volatile organic solvent and a non-volatile organic solvent, a gelling agent comprising inorganic fine particles, and from 10 to 60% by weight of a resin soluble in the organic solvent used.