Abstract: In a water-based ink composition of the present invention, 2.5 to 50 wt % of white-colored resin particles and 2.5 to 50 wt % of film-forming resin emulsions in a solid content are contained with respect to the total amount of the ink, the ratio of said white-colored resin particles to film-forming resin emulsions is 1:0.2 to 1:3, and not less than 20 wt % of said white-colored resin particles and film-forming resin emulsions in a solid content are contained in total.

Abstract: A tip unit (1) incorporated in a liquid applicator such as a ball-point pen, the tip unit being capable of an increased rate of liquid discharge with no leaking or clogging problem. To achieve it, the tip unit (1) is accommodated in a tip body (11) having a ball housing (15), a ball (10), a capillary hole (16), and a proximal bore, the ball housing (15) being a passage for allowing liquid to flow therethrough, the ball (10) being rotatively held in the ball housing (15). The ball housing (15) is provided with at least one ink channel (47) adapted to communicate the ball housing (15) with the capillary hole (16) or the proximal bore. The ball housing (15) has a ball resting seat (45) and a side wall (41) that are connected by a connecting surface (71) having a shape of a truncated conical surface with its apex toward the distal end of the tip unit (1).

Abstract: An oil-based ink composition for writing instruments is provided that is capable of improving storage stability of an ink, while maintaining a leveling property even when a soluble gelling agent is used. The oil-based ink composition for writing instruments comprises a colorant, a resin, an organic solvent and a gelling agent, wherein said organic solvent(s) is (are) hydrocarbons solvent(s), and in particular, at least one species of the solvent selected from the group of aliphatic hydrocarbons solvent(s), alicyclic hydrocarbons solvent(s), aromatic hydrocarbons solvent(s), and halogenetad hydrocarbons solvent(s), said gelling agent(s) comprises (comprise) soluble gelling agent(s) soluble to the above organic solvent(s) and insoluble gelling agent(s) insoluble to the above organic solvent(s), and the above insoluble gelling agent(s) is (are) urea-modified thixotropic agent(s).

Abstract: A method for producing a tip unit for a liquid applicator including: a first process of shaping the contour of a tip body in the form of a truncated conical surface; a second process of forming a ball housing having an open end at its distal end in the tip body; a third process of placing a ball into the ball housing; a fourth process of scraping the peripheral side of the distal end portion of the tip body to form a peripherally scraped portion after the first process; and a fifth process of deforming the peripherally scraped distal end portion of the tip body toward the ball.

Abstract: A coating tool that includes an ink containment tube, an oily ink and a backflow inhibiting material. The ink is in contact with the inhibiting material. The ink containment tube has a boundary which is in contact with the oily ink and the backflow inhibiting material. The boundary contains polyvinyl alcohol and fluorine-based surfactants, the oily ink contains a colorant, a resin, an organic solvent, and a gelling agent, and the backflow inhibiting material consists of base material components and a gelling agent which contains polyacrylic acid, the polyacrylic acid being present in an amount of 0.1 to 3 wt % with respect to the total amount of said backflow inhibiting material.

Abstract: The ink of the present invention comprises at least a three-dimensional film-forming component and water, comprises an adhesive synthetic resin emulsion as said three-dimensional film-forming component, and comprises at least 30% by weight of said adhesive synthetic resin emulsion on the basis of the solid content with respect to the total amount of the ink, and minimum film-forming temperature (MFT) of said adhesive synthetic resin emulsion is not greater than 25° C. and further, said ink comprises 1 to 3% by weight of a film-forming assistant with respect to the total amount of the ink.

Abstract: In a water-based ink composition of the present invention, 2.5 to 50 wt % of white-colored resin particles and 2.5 to 50 wt % of film-forming resin emulsions in a solid content are contained with respect to the total amount of the ink, the ratio of said white-colored resin particles to film-forming resin emulsions is 1:0.2 to 1:3, and not less than 20 wt % of said white-colored resin particles and film-forming resin emulsions in a solid content are contained in total.

Abstract: A tip unit (1) incorporated in a liquid applicator such as a ball-point pen, the tip unit being capable of an increased rate of liquid discharge with no leaking or clogging problem. To achieve it, the tip unit (1) is accommodated in a tip body (11) having a ball housing (15), a ball (10), a capillary hole (16), and a proximal bore, the ball housing (15) being a passage for allowing liquid to flow therethrough, the ball (10) being rotatively held in the ball housing (15). The ball housing (15) is provided with at least one ink channel (47) adapted to communicate the ball housing (15) with the capillary hole (16) or the proximal bore. The ball housing (15) has a ball resting seat (45) and a side wall (41) that are connected by a connecting surface (71) having a shape of a truncated conical surface with its apex toward the distal end of the tip unit (1).

Abstract: The invention provides a coating tool in which an oily ink and a backflow inhibiting material contacting with said ink are contained, wherein the above mentioned ink containment tube has a boundary which contacts with said oily ink and said backflow inhibiting material, the above mentioned oily ink contains polyvinyl alcohol and fluorine-based surfactants said boundary contains polyvinyl alcohol and fluorine-based surfactants, said oily ink contains a colorant, a resin, an organic solvent, and a gelling agent, and at least an organic solvent among aliphatic hydrocarbon-based solvent or an alicyclic hydrocarbon-based solvent is contained as said organic solvent, and a metal soap is contained as said gelling agent, and said backflow inhibiting material consists of base material components and a gelling agent which contains polyacrylic acid, and the above mentioned plyacrylic acid is contained in 0.1 to 3 wt % with respect to the total amount of said backflow inhibiting material.

Abstract: A method for producing a tip unit (1) for a liquid applicator in a stable and easy process, the tip unit (1) being capable of increasing the rate of liquid discharge is provided. The method includes at least five processes; that is, a first process of shaping the contour of a tip body (11) in the form of a truncated conical surface; a second process of forming a ball housing (15) having an open end at its distal end in the tip body (11); a third process of placing a ball (10) into the ball housing (15); a fourth process of scraping the peripheral side of the distal end portion of the tip body (11) to form a peripherally scraped portion (55) after the first process; and a fifth process of deforming the peripherally scraped distal end portion of the tip body (11) toward the ball (10).

Abstract: The ink of the present invention comprises at least a three-dimensional film-forming component and water, comprises an adhesive synthetic resin emulsion as said three-dimensional film-forming component, and comprises at least 30% by weight of said adhesive synthetic resin emulsion on the basis of the solid content with respect to the total amount of the ink, and minimum film-forming temperature (MFT) of said adhesive synthetic resin emulsion is not greater than 25° C. and further, said ink comprises 1 to 3% by weight of a film-forming assistant with respect to the total amount of the ink.

Abstract: The present invention provides erasable aqueous color material composition for scratching off comprising pigment particles with opacifying property and aqueous emulsions of resins with lump coagulation property, wherein said pigment particles with opacifying property are scaly aluminum particles or synthetic resin particles, and said aqueous emulsions of resins with lump coagulation property are aqueous emulsions of styrene butadiene rubber or carboxy modified styrene butadiene rubber.