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,

##STR00001##

wherein R.sup.1 represents a substituted or unsubstituted alkyl group, aralkyl group or aryl group, and R.sup.2 represents a hydrogen atom or an alkyl group.

An object of the present invention is to provide a recording material or a recording sheet using, as a color-developing agent, a non-phenol-based compound good in color developing performance and the like. A compound represented by the following formula (I) is used as the color-developing agent: ##STR00001##
(wherein X represents CH.sub.2 or the like; R.sup.1 to R.sup.3 each independently represent a hydrogen atom, a halogen atom or the like; n1 and n3 each independently represent any integer of 1 to 5; two groups represented by R.sup.3 adjacent to each other on a benzene ring optionally bond to each other to form an optionally substituted 6-membered ring; and n2 represents any integer of 1 to 4).

The presently claimed invention relates to a color developer, a process for its manufacture and its use as a component in heat sensitive recording material. The heat sensitive recording material is useful for thermographic printing.

A reversible recording medium of an embodiment of the disclosure includes a support base, and a recording layer provided on the support base and reversibly changing between a recorded state and a deleted state. The recording layer includes a photothermal conversion material including one or more of a compound having a phthalocyanine skeleton, a compound having a squarylium skeleton, a compound having a cyanine skeleton including, in a molecule, one or both of a counter ion of SbF.sub.6, PF.sub.6, BF.sub.4, ClO.sub.4, CF.sub.3SO.sub.3 and (CF.sub.3SO.sub.3).sub.2N and a methine chain containing a five-membered ring or a six-membered ring, and an inorganic compound; a coloring compound having an electron-donating property; and a color developing/quenching agent having an electron-accepting property and including at least one salicylic acid compound represented by the general formula (1) and including a linear hydrocarbon group having 25 to 34 carbon atoms via a linking group containing an amide moiety.

A description is given of a heat-sensitive recording material, comprising phenol-free organic color developers, more particularly comprising a color developer mixture comprising phenol-free organic color developers, of a heat-sensitive recording layer and also of a coating composition for producing it, of the use of the heat-sensitive recording material, of the use of an organic color developer of a formula I for improving the resistance of the printed image of a heat-sensitive recording material, and of a method for producing heat-sensitive recording material.

The invention relates to a self-adhesive, heat-sensitive recording material, comprising a carrier substrate, a heat-sensitive, color-forming layer that is applied on one side of the carrier substrate and contains at least a non-phenolic color developer in and at least one color former, a siliconized layer on the upper side of the heat-sensitive, color-forming layer that is applied on the carrier substrate, as well as an adhesive layer on the side of the carrier substrate facing away from the heat-sensitive, color-forming layer.

A color laser markable article includes a color laser markable layer provided on a support, the laser markable layer including an infrared absorbing compound; a leuco-dye; and an acid generating compound, wherein the acid generating compound has a structure according to Formulae (I) or (II): ##STR00001##
wherein R1 and R3 independently represent an optionally substituted alkyl group, an optionally substituted (hetero)cyclic alkyl group, an optionally substituted (hetero)aryl group, an optionally substituted aralkyl group, an optionally substituted alkoxy group, an optionally substituted (hetero)cyclic alkoxy group, or an optionally substituted (hetero)aryl group; R2, R4 and R5 independently represent an optionally substituted alkyl, an optionally substituted (hetero)cyclic alkyl group or an optionally substituted aralkyl group; and R1 and R2, R4 and R5, R3 and R4, and R3 and R5 may represent the necessary atoms to form a ring.

A new leuco dye produces a yellow color while demonstrating also exceptional light and thermal stability under light.

A new leuco dye produces a yellow color while demonstrating also exceptional light and thermal stability under light.

A heat-sensitive recording material including a web-shaped substrate having a front side and an opposite reverse side, and at least one heat-sensitive recording layer on either or both of the sides of the web-shaped substrate. The heat-sensitive recording layer contains at least one dye precursor at least one salicylic acid derivative as a (color) developer reactive with this at least one dye precursor, and polyvinylpyrrolidone as auxiliary component augmenting the (color) developer the at least one salicylic acid derivative is 3,5-di(α-methylbenzyl)salicylic acid.