The invention relates to a heat-sensitive recording material, comprising a carrier substrate and a heat-sensitive colour-forming layer, which contains at least one colour former and at least one phenol-free colour developer, characterised in that the at least one colour developer is the compound of formula (A), Ar(NH—CO—NH—CO—NH—Ar.sup.1).sub.n (A), wherein Ar is an unsubstituted or substituted phenyl or naphthyl group, Ar.sup.1 is an unsubstituted or substituted phenyl, naphthyl, pyridyl, thiazolyl or benzothiazolyl group, and n is 1 or 2.

A coating composition for producing a heat-sensitive recording material and to a corresponding heat-sensitive recording layer. The coating composition includes one or more color developers, one or more dye precursors, one or more specific fatty acid amides, and one or more (additional) specific sensitizers. A heat-sensitive recording material including a carrier substrate and a heat-sensitive recording layer, to the use of specific fatty acid amides in order to increase the grease resistance of a heat-sensitive recording material or a heat-sensitive recording layer, and to a method for producing a heat-sensitive recording material or a heat-sensitive recording layer.

An object of the present invention is to provide: a developer that can provide a thermosensitive recording material excellent in color development sensitivity and storage stability; and a thermosensitive recording material obtained using the developer. The object is achieved by a developer including a compound represented by the following Formula (1).

##STR00001##

In Formula (1), a, A, and L are as follows: a is an integer selected from 1 to 5, A is each independently a fluoro group or a perfluoroalkyl group, and L is any of functional groups represented by the following Formula (2):

##STR00002##

wherein in Formula (2), R is a C.sub.1-C.sub.4 alkyl group, and * represents a binding site to a sulfur atom in Formula (1).

Described are colour developers of formula (I) Ar.sup.1—SO.sub.2—NH—C.sub.6H.sub.4—SO.sub.2—C.sub.6H.sub.4—NH—CO—NH—Ar.sup.2 (I), a heat-sensitive recording material, comprising a carrier substrate and also a heat-sensitive, colour-forming layer comprising at least one colour former and at least one phenol-free colour developer, the at least one colour developer being the compound of formula (I), and a method for producing this heat-sensitive recording material.

A heat-sensitive recording composition and recording material. The recording material comprising a substrate, wherein a heat-sensitive composition comprising color formers, color developers and a sensitizer comprising a combination of ortho-toluenesulfonamide and para-toluenesulfonamide (OPTSA) is deposited onto the surface of the substrate.

The invention relates to a color developer of the formula (I), wherein m and n independently of one another are ≥1, Ar.sup.1 is an unsubstinited or substituted (hetero) aromatic radical, Ar.sup.2 is an unsubstituted or substituted phenyl radical, and Y is at least one (m+n)-times substituted benzene or naphthalene group, and to a heat-sensitive recording material, comprising a supporting substrate and a heat-sensitive color-forming layer containing at least one color former and at least one phenol-free color developer, wherein the at least one color developer is the compound of the formula (I). The invention further relates to a method for producing said heat-sensitive recording material.

##STR00001##

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##

The invention relates to a heat-sensitive recording material, comprising a carrier substrate and at least one heat-sensitive thermal reaction layer, which is applied to at least one side of the carrier substrate and contains at least one fluoran color former, at least one color developer, at least one melting aid, and optionally typical additives, such as lubricants, stabilizers (anti-aging agents), and/or pigments, characterized in that the color developer is dodecyl gallate and the melting aid is an ethylene bis fatty acid amide of formula (I), wherein R.sub.1 and R.sub.2 are CH.sub.3(CH.sub.2).sub.mCH.sub.2 with m=13 and/or 15. The invention further relates to a method for producing said recording material. ##STR00001##

A reversible recording medium according to an embodiment of the present disclosure is a reversible recording medium that includes recording layers and heat-insulating layers that are alternately stacked, in which the recording layers each include a reversible heat-sensitive color developing composition and a first light-heat converting agent. In this reversible recording medium, the recording layers are different from each other in a developing color of their respective reversible heat-sensitive color developing compositions and are different from each other in an absorption wavelength of their respective first light-heat converting agents. This reversible recording medium further includes a heat-generating layer that includes a second light-heat converting agent having an absorption wavelength that is different from the absorption wavelength of the first light-heat converting agent included in each of the recording layers.