Non-phenolic direct thermal recording media have a thermally responsive layer containing a leuco dye and a plurality of non-phenolic developers including 1,3-diphenyl urea (DPU) and urea urethane (UU). This chemistry enables multi-purpose recording materials capable of withstanding multiple different types of environmental conditions or agents—such as a water soak, contact with polyvinyl chloride meat wrapping film, boiling water, dry and humid heat, sunlight, and contact with hand sanitizer. The unique non-phenolic chemistry allows the product's thermally responsive layer to have an ultra-low coat weight, less than 1.48 g/m.sup.2.

A thermosensitive recording medium having a thermosensitive coloring layer containing an electron-donating dye precursor, a radical photopolymerization initiator, and an electron-accepting compound with a radical polymerizable group, wherein the electron-accepting compound with a radical polymerizable group includes a compound A represented by the formula (1):

##STR00001##

Color change compositions that transition from a first to second color state upon application of an applied stimulus are provided. Also provided are substrates having the compositions on a surface thereof, as well as methods of making and using the compositions.

The present invention relates to an N,N′-diurea derivative represented by the following general formula (1) and a method for producing the same. In addition, the present invention relates to a thermosensitive recording material in which a thermosensitive recording layer including a basic dye which is colorless or lightly colored at room temperature and a developer capable of developing color upon contact with the basic dye by heating is provided on a base sheet, wherein the developer is the N,N′-diurea derivative represented by the following general formula (1):

##STR00001##

(wherein R2 is an alkyl group, an aralkyl group, or an aryl group; and A1 is a hydrogen atom or an alkyl group).

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.

##STR00001##

wherein, R.sup.1 to R.sup.10 each independently represent a hydrogen atom, a halogen atom, a nitro group, an amino group, an alkyl group, an alkoxy group, an aryl oxy group, an alkyl carbonyl oxy group, an aryl carbonyl oxy group, an alkyl carbonyl amino group, an aryl carbonyl amino group, an alkyl sulfonyl amino group, an aryl sulfonyl amino group, a monoalkyl amino group, a diakyl amino group, or an aryl amino group.

A heat-sensitive recording material including a substrate, a heat-sensitive recording layer which includes N-(4-methylphenylsulfonyl)-/V-(3-(4-methylphenylsulfonyloxy)pheny-purea and/or N42-(3-phenylureido)phenyl]benzol sulfonamide, and an intermediate layer which is arranged between the substrate and the heat-sensitive recording layer and which includes calcined aluminum silicate, and a method for producing a heat-sensitive recording material and to the use of calcined aluminum silicate in an intermediate layer of a heat-sensitive recording material.

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.