Mitsubishi Pencil Company, Limited

Hisato Haga

Yusuke Nakata

Kensuke Inoue

Tomoaki Horie

Tetsuji Murase

Sho Shibusawa

An aqueous ink composition for writing instruments containing an aqueous dispersion of colored resin fine particles, the colored resin fine particles containing at least a cyclohexyl (meth)acrylate monomer and a basic dye or an oil-soluble dye, the cyclohexyl (meth)acrylate monomer being contained in an amount of 30 mass % or greater relative to an amount of a polymerizable polymer component in the colored resin fine particles, and the colored resin fine particles further containing a terpene phenol resin.

Aqueous ink composition for writing instruments

A writing instrument may be capable of preventing dye deposition to a pen core and highly achieving both inhibition of ink discoloration due to the dye deposition and improved writing feeling without reducing writing performance. Such a writing instrument may be equipped with a pen core and loaded with a water-based ink composition, wherein the water-based ink composition contains colored resin particles formed by polymerization of a monomer comprising at least cyclohexyl (meth)acrylate, enclosing a basic dye, an oil-soluble dye or an acid dye, and further contains an anionic surfactant.

Writing instrument

Provided is an aqueous ink composition for writing instruments which is excellent in an antibacterial property and an antifungal property without damaging storage stability and writing performances. The aqueous ink composition for writing instruments according to the present invention is characterized in that at least particles comprising principally a polymer represented by the following Formula (I) are contained as an active ingredient and that a content thereof is 0.1 to 30 mass %: wherein R is an alkyl group having 2 to 8 carbon atoms.

Provided is an aqueous dispersion of colored particles suitable for colorants for writing instrument inks, inkjet inks, painting materials, aqueous coatings, and the like. The aqueous dispersion of colored particles includes a polymer having at least a unit of a monomer derived from a dye having a polymerizable unsaturated group. The monomer derived from the dye is preferably derived from the compound represented by General Formula (1) below: where Dye represents a dye residue, Rrepresents a hydrogen atom or a methyl group,Yrepresents &#x2014;O&#x2014; or &#x2014;NR&#x2014;, where Rrepresents a hydrogen atom or an alkyl group,Arepresents an alkylene group which is unsubstituted or substituted by at least one group selected from &#x2014;OCO&#x2014;, &#x2014;COO&#x2014;, &#x2014;NHCONH&#x2014;, and the like in the chain thereof and/or at the terminal thereof, and/or a hydroxy group.

Aqueous dispersion of colored particles

Provided is a dispersion liquid of colored resin fine particles for an aqueous ink having excellent stability and a sufficient drawn line intensity; an aqueous ink composition for a writing instrument such as felt-tip pens, marking pens, and ballpoint pens using the dispersion liquid of the colored resin fine particle as a colorant; and a writing instrument loaded with the composition. The dispersion liquid of colored resin fine particles for an aqueous ink includes colored resin fine particles dispersed in water, the colored resin fine particles composed of at least a cyclohexyl (meth)acrylate monomer, and a basic dye or an oil-soluble dye, in which the content of the cyclohexyl (meth)acrylate monomer is 30% by mass or more, and the content of the basic dye or the oil-soluble dye is 15% by mass or more based on the total polymer component constituting the colored resin fine particles.

Dispersion liquid of colored resin fine particles for aqueous ink, and aqueous ink composition for writing instruments using same

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.

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Yokohama, Japan

Hisato Haga