Provided is an aqueous ink composition for a writing instrument which is excellent in a drying property of drawn lines and a low temperature stability of the ink while inhibiting the pen tip from drying and which prevents the drawn lines from causing feathering and strike-through. The aqueous ink composition for a writing instrument described above contains at least a colorant, trimethylglycine, pentaerythritol, 10% by mass or less of a water-soluble organic solvent and water.

A thermochromic writing instrument including a writing body, storing a thermochromic ink therein, stored in a barrel; an operation body provided in the barrel to be operated to longitudinally move the writing body; a nib of the writing body configured to be capable of appearing from a front end of the writing instrument, wherein the writing instrument 1 further includes a friction unit, for rubbing handwriting in the thermochromic ink and capable of thermally changing the color of the handwriting by frictional heat generated at that time, and at least one clip body as the operation body, the friction unit 10 is provided at a rear end of the barrel, and the clip body is provided in an area other than the rear end of the barrel.

A thermochromic writing instrument including a writing body, storing a thermochromic ink therein, stored in a barrel; an operation body provided in the barrel to be operated to longitudinally move the writing body; a nib of the writing body configured to be capable of appearing from a front end of the writing instrument, wherein the writing instrument 1 further includes a friction unit, for rubbing handwriting in the thermochromic ink and capable of thermally changing the color of the handwriting by frictional heat generated at that time, and at least one clip body as the operation body, the friction unit 10 is provided at a rear end of the barrel, and the clip body is provided in an area other than the rear end of the barrel.

The invention has disclosed a kind of temperature-sensitive erasable gel ink, including temperature-sensitive microcapsule granules, dispersing agent, humectant, foam suppressor, rheological additives, lubricant, anticorrosive agent, anti-freezing agent, deionized water and pH regulator. Since a great amount of temperature-sensitive microcapsule granules are added to the gel ink of the invention, the handwriting is clearer and more distinct. Meanwhile, under the condition that there is great quantity of temperature-sensitive microcapsule granules, defects that the traditional temperature-sensitive microcapsule granules are unevenly dispersed and easy to subside are overcome, assuring the stability of the ink and smooth writing.

A writing, marking and/or drawing liquid for writing implements, especially for capillary pens, which has a viscosity of less than 50 mPas (Brookfield, 20 C., CPE-40 plate-cone), contains a resin mixture dissolved in a solvent matrix having at least one solvent. Wherein the resin mixture contains a first resin in the form of a modified resin ester and/or a dissolved polyester resin and a second resin in the form of a maleate resin and/or a rosin, especially a phenol-modified rosin. Additives are present in the form of at least one fluorosurfactant as wetter and at least one polyethersiloxane copolymer as glidant.

A writing, marking and/or drawing liquid for writing implements, especially for capillary pens, which has a viscosity of less than 50 mPas (Brookfield, 20 C., CPE-40 plate-cone), contains a resin mixture dissolved in a solvent matrix having at least one solvent. Wherein the resin mixture contains a first resin in the form of a modified resin ester and/or a dissolved polyester resin and a second resin in the form of a maleate resin and/or a rosin, especially a phenol-modified rosin. Additives are present in the form of at least one fluorosurfactant as wetter and at least one polyethersiloxane copolymer as glidant.

The present application describes a composition and method thereof to make low cost environment friendly and highly safe conducive ink by using micro-sized silver particles, water, edible level thickener, water-based solvent, water-based resin and surfactant. The conductive ink may be written by various kinds of writing devices like gel pen, ball pen etc. on various substrates like paper, plastic, metal, etc. form a conductive trace. As additional features of the present application, the composition comprises erasable conductive ink, which is fast curing and conductive immediately upon application, having multiple applications for educational purpose to help students have a better understanding of how electronic work and even design their own electronics conveniently.

The present application describes a composition and method thereof to make low cost environment friendly and highly safe conducive ink by using micro-sized silver particles, water, edible level thickener, water-based solvent, water-based resin and surfactant. The conductive ink may be written by various kinds of writing devices like gel pen, ball pen etc. on various substrates like paper, plastic, metal, etc. form a conductive trace. As additional features of the present application, the composition comprises erasable conductive ink, which is fast curing and conductive immediately upon application, having multiple applications for educational purpose to help students have a better understanding of how electronic work and even design their own electronics conveniently.

A marking pen, comprising: a shaft cylinder; a porous pen core accommodated in the shaft cylinder, and configured to project from, and retract into, an opening part provided at a tip end of the shaft cylinder; an inner cotton accommodated in the shaft cylinder, and filled with an aqueous ink composition to be fed to the pen core, the aqueous ink composition including a water soluble organic solvent in an amount of from 20 mass % to 60 mass %; and a delivery mechanism configured to cause a tip end of the pen core to project from, and retract into, the opening part.

A marking pen, comprising: a shaft cylinder; a porous pen core accommodated in the shaft cylinder, and configured to project from, and retract into, an opening part provided at a tip end of the shaft cylinder; an inner cotton accommodated in the shaft cylinder, and filled with an aqueous ink composition to be fed to the pen core, the aqueous ink composition including a water soluble organic solvent in an amount of from 20 mass % to 60 mass %; and a delivery mechanism configured to cause a tip end of the pen core to project from, and retract into, the opening part.