Abstract: A water based ink composition for a ballpoint pen containing ?-carrageenan in addition to a dye, water and a water-soluble organic solvent. When used in the ball point pen, the ink composition satisfies an ink drooling prevention and a drying resistance which are mutually incompatible functions and is excellent in writing performance regardless of containing a dye as a coloring agent. The ink composition (c) is used, for example, by accommodating a refill (12) whose ink accommodating tube (18) is filled with the ink composition and which is further loaded with an ink backflow-preventing member (20) in the ballpoint pen (10) whose writing edge is retracted and extruded from a front end opening of a barrel (21).

Abstract: A water based ink composition for a ballpoint pen containing ?-carrageenan in addition to a dye, water and a water-soluble organic solvent. When used in the ball point pen, the ink composition satisfies an ink drooling prevention and a drying resistance which are mutually incompatible functions and is excellent in writing performance regardless of containing a dye as a coloring agent. The ink composition (c) is used, for example, by accommodating a refill (12) whose ink accommodating tube (18) is filled with the ink composition and which is further loaded with an ink backflow-preventing member (20) in the ballpoint pen (10) whose writing edge is retracted and extruded from a front end opening of a barrel (21).

Abstract: A water-based ink composition for ballpoint pen which has a colorant, water, a water soluble organic solvent and, as a shear-thinning tackifier, a polysaccharide, wherein the polysaccharide exists in the ink as particles having an average particle size less than 5 ?m, and a water-based ballpoint pen using the composition.

Abstract: Provided are a water-based ink composition for ballpoint pen which has a colorant, water, a water soluble organic solvent and, as a shear-thinning tackifier, a polysaccharide, wherein the polysaccharide exists in the ink as particles having an average particle size less than 5 ?m, and a water-based ballpoint pen using the composition.

Abstract: An ink follower composition to be provided at the rear end of an ink held directly in an ink container of a writing instrument and capable of going forward with consumption of the ink. The composition comprises at least one selected from an ethylene-?-olefin co-oligomer, an ?-olefin oil, a purified mineral oil and a polybutene, and added thereto a specific fatty acid amide. This composition can simultaneously satisfy the two important performances conflicting with each other, the ink flow-back preventive performance and the ink follow-up performance.

Abstract: An ink follower composition to be provided at the rear end of an ink held directly in an ink container of a writing instrument and capable of going forward with consumption of the ink. The composition comprises at least one selected from an ethylene-&agr;-olefin co-oligomer, an &agr;-olefin oil, a purified mineral oil and a polybutene, and added thereto a specific fatty acid amide. This composition can simultaneously satisfy the two important performances conflicting with each other, the ink flow-back preventive performance and the ink follow-up performance.

Abstract: Disclosed is a water-based ball-point pen ink composition which gives a smooth writing touch and shows various satisfactory writing performance, comprising a colorant, water, and as an agent for imparting shear-thinning properties at least one member selected from sulfosuccinates represented by the following general formula (1): wherein each R represents an alkyl or alkenyl group having 7 to 18 carbon atoms and X represents an alkali metal or an amine, the content of the at least one member being from 5 to 50% by weight.

Abstract: An ink follower composition for ballpoint pens which comprises (1) a hardly volatile liquid and (2) expansible synthetic mica having a quaternary ammonium ion introduced therein or an ink follower composition for ballpoint pens which comprises (1) a hardly volatile liquid, (3) synthetic mica, and (4) a thickener, and a ballpoint pen having the ink follower composition. The ink follower composition follows ink without leaving ink behind on the inner wall of an ink container.

Abstract: An ink follower composition for ballpoint pens which comprises a hardly volatile liquid and aluminum silicate added therein. The ink follower composition for ballpoint pens of the present invention has very little temperature dependence of viscosity, undergoes no liquid separation due to changes in temperature, etc. and therefore follows ink while retaining the interface with the ink and preventing the ink from adhering to the inner wall of the ink tube until the ink runs out.

Abstract: A ballpoint pen tip including a metallic pipe having a plurality of inwardly projecting portions at a neighborhood of a front end portion of the pipe at regular intervals, and a front end edge portion at a front end of the pipe, and a ball rotatably held between the front end edge portion and the plurality of inwardly projecting portions, wherein the pipe satisfies a relation of A/T.ltoreq.5.8 where A is an outer diameter of the ball and T is a thickness 10 of the pipe, and also the relation of B/T.ltoreq.2.3 where B is a diameter of a virtual inscribing circle contacting a top of the plurality of inwardly projecting portions and T is the same as above.

Abstract: A ballpoint pen tip including a metallic pipe having a plurality of inwardly projecting portions at a neighborhood of a front end portion of the pipe at regular intervals, and a front end edge portion at a front end of the pipe, and a ball rotatably held between the front end edge portion and the plurality of inwardly projecting portions, wherein the pipe satisfies a relation of A/T.ltoreq.5.8 where A is an outer diameter of the ball and T is a thickness 10 of the pipe, and also the relation of B/T.ltoreq.2.3 where B is a diameter of a virtual inscribing circle contacting a top of the plurality of inwardly projecting portions and T is the same as above.