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.

In one aspect, the present invention relates to a thermosensitive recording medium comprising at least: —a support layer; —a thermosensitive colouring layer over the support layer, the thermosensitive colouring layer containing a leuco dye; and —a protective layer over the thermosensitive colouring layer; wherein the thermosensitive colouring layer comprises a developer having the general formula (I) below: wherein R.sub.1 to R.sub.3 each independently represent a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 alkoxyl group, a C1-C6 fluoroalkyl group; characterized in that the protective layer comprises particles of wax with an average particle size of at least 0.05 μm and at most 2.0 μm. In further aspects, the present invention relates to a label for attachment to a product comprising the thermosensitive recording medium of the invention, and to a consumer product package to which a thermosensitive recording medium or a label of the invention has been attached.

##STR00001##

Disclosed is a heat-sensitive recording material comprising an undercoat layer and a heat-sensitive recording layer in this order on a support, the undercoat layer containing hollow particles, a binder, and an inorganic pigment I, the heat-sensitive recording layer containing a leuco dye, a developer, and an inorganic pigment II, and the heat-sensitive recording layer containing an N,N′-diarylurea-based compound represented by the following formula (1):

##STR00001## wherein R.sub.2s may be the same or different, and each represents C.sub.1-12 alkyl, C.sub.7-12 aralkyl, or C.sub.6-12 aryl, and the aralkyl and the aryl may be each substituted with C.sub.1-12 alkyl, C.sub.1-12 alkoxy, C.sub.6-12 aryl, or halogen; A.sub.1s may be the same or different, and each represents hydrogen or C.sub.1-4 alkyl, as the developer, and a pigment with an oil absorption of 130 ml/100 g or less as the inorganic pigment II.

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 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##

Disclosed is a heat-sensitive recording material comprising an undercoat layer and a heat-sensitive recording layer formed in this order on a support, the undercoat layer containing hollow plastic particles and a binder, the heat-sensitive recording layer containing a leuco dye and a developer, and the heat-sensitive recording material having an elastic modulus of 200 N/mm.sup.2 or less as measured by a nanoindentation method.

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##

The invention relates to a compound of the formula (I) Ar(NHSO.sub.2Ar.sup.1)l(SO.sub.2NHAr.sup.1).sub.m(NHC(O)NHAr.sup.2).sub.n (I), wherein l and m independently of one another are 0, 1, 2, 3, and/or 4 and the sum of l+m is equal to or more than 1, n is 2, 3, 4, or 5, Ar is a benzol group which is substituted (l+m+n) times, Ar.sup.1 is an unsubstituted or substituted aromatic group, and Ar.sup.2 is an unsubstituted or substituted phenyl group or a benzoyl group. The invention also relates to a heat-sensitive recording material comprising a carrier substrate and a heat-sensitive color-forming layer which contains at least one color former and at least said color developer.

A reversible recording medium according to an embodiment of the present disclosure includes a first recording layer to be colored in a first color, a second recording layer to be colored in a second color, the second color being different from the first color, and a first intermediate layer provided between the first recording layer and the second recording layer, the first intermediate layer including a plurality of layers respectively containing materials different from each other.

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(NHCONHCONHAr.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.