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.

Hollow resin particles for thermosensitive recording media containing a thermoplastic resin shell and a hollow part surrounded by the shell. The hollow resin particles contain a thermally-vaporizable hydrocarbon in an encapsulation ratio of at least 0.2 wt %. The hollow resin particles preferably have a mean volume particle size ranging from 0.1 to 10 μm.

A reversible recording medium according to an embodiment of the present disclosure includes: a recording layer including a coloring compound having an electron-donating property, a color developing/quenching agent having an electron-accepting property, a photothermal conversion agent, and a macromolecular material; and an ultraviolet absorbing layer provided on the recording layer, the macromolecular material including an organic material that has solubility of 20 wt % or more and 80 wt % or less at 25° C. or less and contains 0.5 wt % or less of chlorine atoms, fluorine atoms, and sulfur atoms in a molecule.

A recording material and a recording sheet having excellent color-developing performance and storage stability and particularly having excellent heat-resistance of background. The recording material contains a color former (A), a compound represented by formula (I) (B), and a compound represented by formula (II) (C). ##STR00001##

A heat-sensitive recording material having i) a supporting substrate and ii) a heat-sensitive recording layer, where the heat-sensitive recording layer comprises a colour former and a colour developer mixture and the colour developer mixture comprises a) N-[2-(3-phenylureido)phenyl]benzenesulfonamide (compound of the formula (I)), where the compound of the formula (I) is in a crystalline form having an absorption band at 3401 20 cm 1 in the IR spectrum, and b) N-(4-methylphenylsulfonyl)-N-(3-(4-methylphenylsulfonyloxy)phenyl) urea (compound of the formula (II)), where the mass ratio between the compound of the formula (I) and the compound of the formula (II) is 0.5:99.5 to 35:65 or 99.5:0.5 to 65:35.

Provided is a thermosensitive recording medium, which is excellent in color developing property, especially excellent in bar code readability, under severe environment, further, excellent in resistance to discoloration under severe environment. 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 comprises, as the electron accepting color developing agent, a specific sulfone compound and a phenolic compound in a specific ratio, wherein the phenolic compound contains two or more hydroxyl groups and two or more diphenylsulfone backbone but contains neither urethane bond nor urea bond. The thermosensitive recording layer optionally may further comprise a specific urea-urethane-based compound.

A coating composition for producing a layer composite, including a) a modified or unmodified polyvinyl alcohol, b) an alkylene/(meth)acrylic acid copolymer, c) a crosslinker, and d) one, two or more than two, pigments. The layer composite is used as food packaging, entry ticket, gaming ticket, car park ticket, or the like. A mixture of alkylene/(meth)acrylic acid copolymer and modified or unmodified polyvinyl alcohol is used in a layer of a layer composite, to the use of a coating composition for producing a layer composite.

A thermochromic composition including a dye molecule; a matrix, wherein the matrix comprises a material having a defined melting point; and an optional developer. A process for preparing a thermochromic composition, including providing a dye; heating a matrix above its melting point; adding the heated matrix to the dye until the dye dissolves in the matrix; optionally, adding a developer; wherein the thermochromic composition exhibits a first color at a first temperature and a second color at a second temperature; wherein the first color and the second color are different; and wherein the first temperature and the second temperature are different.

In the present invention, there is provided a use of 1,1,1-tris(4-hydroxyphenyl)ethane in a composition in the formation of an image on a substrate having said composition applied thereon, wherein the image is formed upon exposure of the composition to NIR or IR radiation, and wherein the image is capable of being retained on the substrate for at least 1 day under conditions of at least 50% relative humidity. The present invention is further directed towards compositions comprising 1,1,1-tris(4-hydroxyphenly)ethane, in addition to substrates, methods of forming an image and printing processes comprising said compositions.

A recording material and a recording sheet having excellent color-developing performance and storage stability and particularly having excellent heat-resistance of background. The recording material contains a color former (A), a compound represented by formula (I) (B), and a compound represented by formula (II) (C).

##STR00001##