A marking system comprises a substrate having a surface coated with a color-triggering developer and a deactivating ink composition; and a marking composition comprising at least one color precursor. At least one “non-color developing portion” of the surface is coated with both the color-triggering developer and the deactivating ink composition, and at least one “color-developing portion” of the surface is coated with the color-triggering developer and is not coated with the deactivating ink composition. Color development occurs at the color-developing portion(s) and does not occur at the non-color developing portion(s) upon application of the marking composition to the surface of the substrate.

Provided are thermochromic color-memorizing composition and thermochromic color-memorizing microcapsule pigment encapsulating the same, the thermochromic color-memorizing composition including: (a) an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) an ester compound represented by the following formula (1) as a reaction medium which controls color reaction between the components (a) and (b):

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A thermochromic ink composition includes, in a liquid medium, known as solvent, a dispersion of thermochromic microcapsules incorporating at least one leuco-dye and a thermoplastic binder selected from the group containing polyacrylic polyesters, polyurethanes and copolymers thereof. The composition is characterized in that the solvent is aprotic. A a method for producing a card and such a card incorporating at least one thermochromic pattern produced with a thermochromic ink composition are also described.

The present invention relates to thermal recording materials comprising (in order): a support (base) layer; one or more “undercoat” layers; a thermal layer (thermosensitive coloring layer); and one or more “protective” layers, wherein the thermal recording material contains an aminocarboxylic and/or phosphorus-based chelating agent.

The thermal (thermosensitive) recording materials of the invention show enhanced plasticizer resistance and/or preprint uniformity.

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.

Provided is a thermosensitive recording medium including a thermosensitive coloring layer containing an electron-donating dye precursor, an electron-accepting compound, a radical polymerizable compound and a photoradical polymerization initiator, in which the radical polymerizable compound is a compound that is solid at 25° C., and the radical polymerizable compound is contained in the thermosensitive coloring layer in a state of encapsulating at least one of the electron-donating dye precursor and the electron-accepting compound.

A recording material and a recording sheet having better color-developing performance, storage stability, etc. A recording material which contains (A) at least one color former, (B) at least one compound selected from the group including compounds represented by the following formula (I), and (C) at least one compound selected from the group including compounds represented by the following formula (II) (wherein R.sup.1 to R.sup.3 each represent a halogen atom, a nitro group, a C.sub.1 to C.sub.6 alkyl group, a C.sub.1 to C.sub.6 alkoxy group, a C.sub.2 to C.sub.6 alkenyl group or a C.sub.1 to C.sub.6 haloalkyl group, n1 and n3 each independently represent any integer of 0 to 5, n2 represents any integer of 0 to 4, and X represents —SO.sub.2—O— or —O—SO.sub.2—). ##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.

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):

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A thermosensitive recording medium 100 includes a support 50, and a first thermosensitive coloring layer 10, a first intermediate layer 15, and a second thermosensitive coloring layer 20 disposed on the support 50 in descending order of distance from the support 50. The first thermosensitive coloring layer 10 and the second thermosensitive coloring layer 20 each contain an electron-donating dye precursor, an electron-accepting compound, a radical-polymerizable compound, and a photoradical polymerization initiator, and the first intermediate layer 15 contains a UV absorber.