Nippon Paper Industries Co., Ltd.

Kentaro Kawasaki

Yoshimi Midorikawa

Kenji Hirai

Yuka Murata

Tadashi Yoshida

Koji Kutsuwa

Provided is a thermosensitive recording medium being excellent in oil resistance among various performances required for the thermosensitive recording medium, and being further excellent in heat resistance, plasticizer resistance, and printing (recording) run-ability. That is a thermosensitive recording medium having a thermosensitive recording layer comprising a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate, wherein the thermosensitive recording layer contains at least two kinds of urea compounds. The two kinds of urea compounds comprise the first urea compound being represented by the following general formula 1, and the second urea compound being represented by the following general formula 2. wherein Rrepresents a substituted or unsubstituted alkyl group, aralkyl group or aryl group, and Rrepresents a hydrogen atom or an alkyl group, wherein Rto Rrepresent a hydrogen atom, a halogen atom, a nitro group, an amino group, an alkyl group, an alkoxy group, an aryloxy group, and the like, and m represents an integer of 0 to 2.

Thermosensitive recording medium

Provided is a thermosensitive recording medium having a sufficient water resistance to moisture and humidity, such as for outdoor use in rainy weather and the like, and also having a superior color developing sensitivity, print image quality when printing at high speed, ink fixability and solvent resistance and the like. As the protective layer comprises a specific silane-modified acrylic resin which is an aqueous emulsion of core-shell type p articles, in a thermosensitive recording medium having a thermosensitive recording layer on a substrate and a protective layer on the thermosensitive recording layer, the thermosensitive re cording medium has a sufficient water resistance and also has a superior color developing sensitivity, print image quality when printing at high speed, ink fixability and solvent resistance and the like.

The present invention provides a thermosensitive recording medium having a high degree of water resistance and excellent surface qualities. The thermosensitive recording medium has a thermosensitive recording layer comprising a colorless or pale colored basic leuco dye and an electron accepting developing agent on a substrate, but does not have a protective layer on the thermosensitive recording layer, and the thermosensitive recording layer further comprises (i) a carboxy-modified polyvinyl alcohol as a binder, (ii) an epichlorohydrin resin and a modified polyamine/amide resin (excluding those contained in the category of epichlorohydrin resin) as crosslinking agents, and (iii) an acrylic resin with a glass transition temperature (Tg) of lower than or equal to 50 degree C. and a minimum film forming temperature (MFT) of higher than or equal to 40 degree C.

Provided is a thermosensitive recording medium having excellent oil resistance among various performances required for the thermosensitive recording medium. The thermosensitive recording medium has a thermosensitive recording layer comprising a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate, wherein the thermosensitive recording layer contains N-[2-(3-phenylureido)phenyl] benzenesulfonamide and an urea-based compound represented by the general formula 1 as the electron accepting color developing agents, wherein Rrepresents a substituted or unsubstituted alkyl group, aralkyl group or aryl group, and Rrepresents a hydrogen atom or an alkyl group.

An inkjet recording medium, comprising an ink-receiving layer containing an inorganic pigment, a binder, an inkjet ink-fixing agent comprising a cationic compound, and organic spherical particles disposed on at least one surface of a base paper, wherein the ink-receiving layer further contains a water-soluble metal salt and 5 parts by weight or more to 15 parts by weight or less of polyvinyl alcohol (A) with a polymerization degree of 700 or less and 20 parts by weight or more to 40 parts by weight or less of polyvinyl alcohol (B) with a polymerization degree of 1200 or more as the binder with respect to 100 parts by weight of the ink-receiving layer; and a volume 50% average particle diameter (D50) as measured by a laser diffraction/scattering method of the organic spherical particles is 15.0 &#x3bc;m or more.

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Tokyo, Japan

Kentaro Kawasaki