A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate and a polyhydrazide. The capsules include a leuco dye and may be used in laser markable compositions.

A three-dimensional structure according to an embodiment of the present disclosure includes a plurality of resin layers including a light curable resin, a coloring compound, a color developing-reducing agent, and a photothermal conversion agent, the plurality of resin layers being stacked.

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##

An object is to provide a thermosensitive recording material and a laminate which are excellent in color development sensitivity and favorable in storage characteristics such as heat resistance, plasticizer resistance, moisture resistance, oil resistance, and grease resistance. A thermosensitive recording material in which a thermosensitive recording layer is provided on a support, wherein the thermosensitive recording layer contains a specific diphenylsulfone compound and an analog compound thereof at a specific ratio. A laminate in which a thermosensitive recording layer is provided on a support, wherein the thermosensitive recording layer contains a specific diphenylsulfone compound and an analog compound thereof at a specific ratio.

The invention relates to a color developer of formula (I), (Ar.sup.1SO.sub.2NH-)m-Y(NHC(O)NHSO.sub.2Ar.sub.2)n (I), wherein Ar.sup.1 is an unsubstituted or substituted aromatic moiety, Ar.sup.2 is an unsubstituted or substituted phenyl moiety, Y is at least an (m+n)-times substituted benzene group or naphthalene group, and Y is substituted in such a way that at least one Ar.sub.2SO.sub.2NHC(O)NH group is in ortho-position with respect to at least one Ar.sup.1SO.sub.2NH group. The invention further 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 one phenol-free color developer, the at least one color developer being the compound of formula (I). The invention further relates to a method for producing said heat-sensitive recording material.

An object is to provide a thermosensitive recording material and a laminate which are excellent in color development sensitivity, which cause less color development in a blank area even at a high temperature, which are also favorable in storage stability of a print area, and which are excellent in contrast between a blank area and a print area. A thermosensitive recording material in which a thermosensitive recording layer is provided on a support, wherein the thermosensitive recording layer contains a specific diphenylsulfone compound and an analog compound thereof at a specific ratio. A laminate in which a thermosensitive recording layer is provided on a support, wherein the thermosensitive recording layer contains a specific diphenylsulfone compound and an analog compound thereof at a specific ratio.

Developing agent precursors and laser markable compositions including such developing agent precursors.

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 invention relates to a compound of the formula (I) Ar(NHSO.sub.2Ar.sup.1)1(SO.sub.2NHAr.sup.1).sub.m(NHC(O)NHAr.sup.2).sub.n (I), wherein 1 and m independently of one another are 0, 1, 2, 3, and/or 4 and the sum of is equal to or more than 1, n is 2, 3, 4, or 5, Ar is a benzol group which is substituted (i+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.

Aspects of the invention include color change compositions having a color former and color developer composition that transitions from a first color state to a second color state upon application of an applied stimulus and an amount of a copolymer sufficient to eliminate background color of the color former and color developer composition during transition from the first color state to the second color state. Methods for preparing and devices employing the color change compositions of the invention are also described.