Abstract: A heat-sensitive recording material having a substrate that carries on its first side at least one heat-sensitive recording layer having at least one dye precursor and at least one color acceptor. The dye precursor and color acceptor react with one another in a color-forming manner under the action of heat. On its second side the substrate has a backcoat containing calcium carbonate. The backcoat is formed of at least two layers, a first layer is applied closer to the substrate and a second layer is applied farther from the substrate. The first layer contains a first calcium carbonate and the second layer contains a second calcium carbonate that differs from the first calcium carbonate.

Abstract: The conventionally constructed thermosensitive recording labels prepared by installing a thermosensitive recording layer on one side of a support material and a tackifier layer on the other side were found to be clearly limited when meeting the demand for improved water and weather resistance. Therefore, the present invention provides a thermosensitive recording label having much better water and weather resistance than conventionally available one. The thermosensitive recording label having a thermosensitive recording layer and a tackifier layer on a transparent film substrate in this order has a superior water and weather resistance.

Abstract: This invention provides 1,1-bis(4-hydroxyphenyl)-1-phenylethane having a crystal form characterized by an X-ray diffraction pattern having one sharp and strong peak at 16.4° and three sharp peaks of intermediate intensity at each of 13°-16° and 17°-20.8° and at least three peaks of intermediate intensity at 22°-23° as a diffraction angle (2?) in an X-ray diffractometry with Cu—K ?-rays, and being capable of giving the storing stability of a colored image and a non-colored portion against heat, water or the like and the low-energy color-developing property suitable for high-speed color development.

Abstract: Provided is a thermal recording material superior in color development sensitivity, and having good preservation properties such as in heat resistance, moisture resistance, water resistance and the like.

Abstract: A heat-sensitive recording material is proposed, which comprises a substrate and a heat-sensitive recording layer that contains color formers and color acceptors, where the color formers are selected from the list comprising: 3-diethylamino-6-methyl-7-anilinofluoran, 3-dibutylamino-6-methyl-7-anilinofluoran, 3-(N-methyl-N-propyl)amino-6-methyl-7-anilinofluoran, 3-(N-ethyl-N-isoamyl)amino-6-methyl-7-anilinofluoran, 3-(N-methyl-N-cyclohexyl)amino-6-methyl-7-anilinofluoran, 3-(N-ethyl-N-tolyl)amino-6-methyl-7-anilinofluoran, and 3-(N-ethyl-N-tetrahydrofuryl)amino-6-methyl-7-anilinofluoran, the heat-sensitive recording layer contains two color acceptors, which are: N-(p-toluenesulfonyl)-N?-3-(p-toluenesulfonyloxyphenyl)urea with the following formula (1): and a urea-urethane compound with the following formula (2): where the ratio of the two color acceptors, i.e.

Abstract: A polymer composite material (10, 110, 210, 310) is described. The material includes a settable matrix material (12), a plurality of reinforcement members (14) and a plurality of capsule members (16). Each capsule member (16) includes a shell layer (22) encapsulating an indicator material (24). The polymer composite material comprises an initial condition in which each shell layer contains the indicator material, and a damaged condition in which at least one shell layer is ruptured, releasing indicator material. The polymer composite material is changed from the initial condition to the damaged condition by the application of a predetermined force to the polymer composite material.

Abstract: The present invention provides coating compositions for marking substrates, which comprises a color former, an amine salt of an organic metal compound, a binder, a solvent, and optionally additional components, wherein the amine salt of the organic metal compound is of formula (I) in which X is silicon or boron, and E and F are the same or different and are selected from the group consisting of a, b, c, d, e, f, g, h in which R6 and R7 are the same or different are hydrogen, C1-4-alkyl, C1-4-alkoxy, halogen, amino or carboxy, and for X=silicon o=1 and p=0, and R1 is aryl, aralkyl or C1-4-alkyl, or o=1 and p=1, and R1 and R2 together form a one residue selected from the group consisting of a, b, c, d, e, f, g and h, and for X=boron o=0 and p=0, and R3, R4 and R5 are the same or different and are hydrogen, C1-12-alkyl, C1-6-hydroxyalkyl, allyl, aralkyl or arylsulfonyl, in which aralkyl or arylsulfonyl can be substituted with C1-4-alkyl, or R3 and R4 together with the nitrogen to which they are attached form a m

Abstract: The present invention provides coating compositions for marking substrates, which comprise a colour former in an amount of from 0.01 to 50%, a metal salt of a carboxylic acid in an amount of from 0.01 to 50%, a binder in an amount of from 1 to 80% and an organic solvent in an amount of from 1 to 99%, wherein each amount is by weight based on the weight of the composition. The present invention also provides a process for the preparation of the composition of the present invention, substrates coated with these compositions and a process for preparing a marked substrate using these compositions.

Abstract: The present invention provides a heat-sensitive recording material with enhanced color developing sensitivity maintaining heat resistance and image storage stability characteristics such as plasticizer resistance and water resistance. The present invention provides a heat-sensitive recording material including at least a substrate and a heat-sensitive color developing layer containing a leuco dye and developers on the front surface of the substrate, wherein as the developers 4-hydroxy-4?-allyloxydiphenyl sulfone is used in combination with a first diphenyl compound represented by formula (1) and/or a second diphenyl compound represented by formula (2).

Abstract: Storage-stable compositions comprising a color developer, an anionic dispersant and a thickening agent as well as heat-sensitive recording materials comprising such compositions, a process for its manufacture and its use.

Abstract: The present invention provides a reversible thermosensitive recording medium including: a support, and a reversible thermosensitive recording layer laid on the support, the recording layer containing a reversible thermosensitive composition, wherein the reversible thermosensitive composition forms a relatively color-developed state and a colorless state depending on a difference in a heating temperature and/or a cooling rate after heating by the use of an electron-donating color-forming compound and an electron-accepting compound; a resin component contained in the reversible thermosensitive recording layer is a resin in which a polyol resin having a hydroxyl value within the range of 100 KOHmg/g to 250 KOHmg/g is crosslinked; and as the electron-accepting compound, a urea compound represented by the following General Formula (1) is used, where “n” is an integer of 23 or greater.

Abstract: The present invention relates to a developer mixture for a thermal recording material, which comprises a mixture of the first organic developer comprising a condensate or a condensed composition represented by the formula (I): wherein R is a lower alkyl group or an aralkyl group, n is an integer of 0 to 5, and X and Y are each a hydrogen atom, an alkyl group or an aryl group, and the second organic developer other than the first organic developer (except 2,2-bis(3-methyl-4-hydroxyphenyl)propane), a developer mixture for a thermal recording material, and a thermal recording material having a heat-coloring layer containing the developer mixture. Using the developer mixture for a thermal recording material of the present invention, a thermal recording material sufficiently satisfying the recent requirement for high sensitivity, and having superior preservation stability of color images and non-image areas can be realized.

Abstract: The present invention provides a thermosensitive recording medium having an excellent image durability, even when used in a severe condition. A thermosensitive recording medium having a thermosensitive color developing layer comprising a colorless or pale colored dye and two kinds of color developing agents on a substrate, wherein the thermosensitive color developing layer contains bis (3-allyl-4-hydroxyphenyl) sulfone and a phenol novolac compound as the color developing agents.

Abstract: The invention provides a heat sensitive recording material comprising heat sensitive recording layer provided on a support and having a hollow particle and a heat sensitive coloring component.

Abstract: A heat-sensitive recording material includes a paper web with recycled fibers and a heat-sensitive recording layer includes color formers and color acceptors. The amount of recycled fiber contained in the paper web is at least 70 percent by weight, and the heat-sensitive recording layer has, as color acceptor, at least 33? percent by weight of N-(p-toluenesulphonyl)-N?-3-(p-toluenesulphonyloxyphenyl)urea in relation to the total content of color acceptors in the heat-sensitive recording layer.

Abstract: The present invention provides a heat-sensitive recording material having a support, a heat-sensitive color-developing layer containing a leuco dye and a developer, and a protective layer, the heat-sensitive color-developing layer and the protective layer being formed on the support, wherein carboxylic-acid-modified polyvinyl alcohol with a weight average degree of polymerization of 100 to 400 and a modification degree of 0.2 mol % to 1.0 mol % is used as a dispersing agent for dispersing the leuco dye.

Abstract: Disclosed herein is a heat-sensitive recording material shows good barcode printability and provides printed images having an excellent milk resistance. The heat-sensitive recording material comprises a heat-sensitive recording layer contains 3,3?-diallyl-4,4?-dihydroxydiphenylsulfone and 1,2-di(methylphenoxy)ethane in a specific amount relative to the leuco dye, and contains a crosslinked diphenylsulfone-based compound in an specific ratio based on the total solid in the heat-sensitive recording layer.

Abstract: A heat-sensitive recording material comprising a support and a heat-sensitive recording layer, the heat-sensitive recording layer comprising a colorless or pale-colored basic dye and a developer, the developer being 4-allyloxy-4?-hydroxydiphenylsulfone, and the heat-sensitive recording layer further comprising a compound represented by formula (I): wherein R1 is an unsubstituted aromatic group, or an aromatic group substituted with at least one member selected from the group consisting of a methyl group and a chlorine atom, and R2 is a divalent organic group.

Abstract: A system for recording and/or transmitting optical data or visual images includes an optical data or visual image recording medium and a light and/or heat source. The medium includes a markable coating established on a substrate. The markable coating includes a leuco dye and a developer precursor including a compound that undergoes rearrangement in response to a stimulus, thereby forming a developer that reacts with the leuco dye. The light/heat source is positioned so as to illuminate and/or heat the medium in a predetermined manner to i) cause photochemical and/or photothermal rearrangement of the developer precursor to form the developer which reacts with the leuco dye to form an optically detectable mark, or ii) cause at least one optically detectable mark previously formed on the markable coating to produce at least one readable pattern.

Abstract: The present invention provides a thermosensitive recording medium with excellent color developing sensitivity, moist heat resistance and plasticizer resistance, as well as excellent heat resistance, background coloring, light resistance and the like in the printed image. A diphenyl sulfone derivative containing a hydroxyl group on one end and an alkoxy group on the other end has a higher melting point than the one containing hydroxyl groups on both ends. As a result, the thermosensitive recording medium obtained using the diphenyl sulfone derivative as the color developing agent in the thermosensitive color developing layer has excellent heat resistance. However the color developing sensitivity of the thermosensitive recording medium generally declines simultaneously, when a color developing agent with a high melting point is ordinarily used.

Abstract: Multi-layer articles capable of forming color images are provided. The articles include a multi-layer construction with at least two layers in which at least one of the layers includes a thermally activatable composition. The thermally activatable composition includes a non-linear light to heat converter composition and a color forming compound. Upon activation with a light source an image forms.

Abstract: Disclosed herein in a preferred embodiment is a recording material comprising a substrate and a coating comprising at least 3 plies, wherein the outermost ply contains nanoparticles and the inner plies together contain at least one color former, at least one color developer, at least one absorber and at least one solubilizer, and no ply contains both a color former and a color developer. Also disclosed is a process for producing the recording material of the invention and also to a laser marking process wherein the recording material is irradiated with a laser.

Abstract: The present invention provides a heat-sensitive recording material comprising a support and a heat-sensitive recording layer, wherein the heat-sensitive recording layer contains a leuco dye and a color developer, the leuco dye is in a form of composite particles comprising the leuco dye and a hydrophobic resin, and the color developer comprises at least 4,4?-cyclohexylidenediphenol and 4,4?-bis(N-p-tolylsulfonylaminocarbonylamino)diphenylmethane.

Abstract: A proposed heat-sensitive recording material comprises a substrate, a heat-sensitive recording layer containing color formers and color acceptors, and a protective layer covering this heat-sensitive recording layer. The heat-sensitive recording layer has, as color acceptor, at least 66? percent by weight of 4,4?-dihydroxydiphenyl sulfone based on the total percentage of color acceptors in the heat-sensitive recording layer, and the protective layer has, as binder, at least 60 percent by weight of diacetone-modified polyvinyl alcohol based on the total percentage of binder in the protective layer.

Abstract: A latent image developing system, methods for imaging and developing images, and systems and methods for blocking or erasing latent images. The latent image developing system includes a substrate containing a colorless image deposited thereon. A developer instrument is used to provide a visible image. The developer instrument includes a developer composition reactive with the colorless image. An image blocking instrument is provided for concealing at least a portion of the visible image. The image blocking instrument is provided by a blocking composition applicator and an aqueous mixture of blocking composition and water.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: A thermosensitive recording material comprising a substrate, a thermosensitive recording layer applied to the front and a back coating which comprises a polyurethane-based-cross-linking component in addition to pigments and binders.

Abstract: A thermosensitive recording material which comprises a color forming layer comprising a color forming substance, which comprises a colorless or light color leuco dye, and a color developer and disposed on a support, wherein a mixture of (A) at least one compound selected from 4-hydroxy-4?-allyloxydiphenylsulfone, 4-hydroxy-4?-ethyloxydiphenyl-sulfone and 4-hydroxy-4?-n-propoxydiphenylsulfone and (B) a diphenylsulfone bridged compound represented by general formula (1): n representing an integer of 1 to 10, in amounts such that the ratio of the amounts by mass of (A) to (B) is 85:15 to 25:75 is used as the color developer. In the thermosensitive recording material, color is formed with a great density, image portions exhibit excellent properties for storage, in particular, excellent resistance to plasticizers, and portions of no color formation exhibit excellent properties for storage, in particular, excellent heat resistance.

Abstract: Compositions and methods for production of color images which are developable with improved marking sensitivity and image contrast are disclosed and described. Specifically, a color forming composition can comprise a polymeric activator phase including a polymer matrix and an activator dissolved therein, a color former phase including a color former, and a radiation absorber in thermal contact with the color former phase. Particularly, the color former phase can be finely dispersed within the polymeric activator phase at an average particle size of less than 2 ?m.

Abstract: (1) A 4-hydroxy-4?-isopropoxydiphenylsulfone developer dispersion characterized by being obtained by wet grinding a 4-hydroxy-4?-isopropoxydiphenylsulfone developer in the presence of at least one compound selected from the group consisting of 1,1,3-tris(2-methyl-4-hydroxy-5-cyclohexylphenyl)butane and 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, or in the presence of 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid; (2) a method for wet grinding a 4-hydroxy-4?-isopropoxydiphenylsulfone developer, characterized by wet grinding a 4-hydroxy-4?-isopropoxydiphenylsulfone developer in the presence of at least one compound selected from the group consisting of 1,1,3-tris(2-methyl-4-hydroxy-5-cyclohexylphenyl)butane and 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, or in the presence of 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid; and (3) a heat-sensitive recording material having a heat-sensitive recording layer containing the developer dispersio

Abstract: The invention provides a thermosensitive recording material having, on a support, a thermosensitive recording layer incuding an electron-donating dye precursor and an electron-accepting compound that makes the electron-donating dye precursor thermally develop a color, wherein the thermosensitive recording layer includes the electron-accepting compound in a ratio of from 5/1 to 20/1 by mass ratio with respect to the electron-donating dye precursor.

Abstract: A color developer for heat sensitive recording which comprises 0.5 to 5 parts by mass of 3-allyl-4-allyloxy-4?-hydroxydiphenylsulfone, 4-allyloxy-3?-allyl-4?-hydroxydiphenylsulfone or a mixture of these compounds per 100 parts by mass of 4-allyloxy-4?-hydroxydiphenylsulfone, a process for producing the color developer and a heat sensitive recording material comprising the color developer in the heat sensitive color forming layer. The color developer and the recording material suppress fog on the background and exhibit excellent color forming property and storage property of image portions.

Abstract: Provided is a thermal recording material superior in color development sensitivity, and having good preservation properties such as in heat resistance, moisture resistance, water resistance and the like.

Abstract: In a thermal recording medium including a basic chromogenic dye, a developer and a sensitizer, a composition for a thermal recording medium which composition contains 50 ppm to 5.0 mass % of 1-(3-methylphenoxy)-2-(4-methylphenoxy)ethane and/or 1,2-bis(4-methylphenoxy)ethane in 1,2-bis(3-methylphenoxy)ethane is used as said sensitizer, whereby the 1,2-bis(3-methylphenoxy)ethane compound is remarkably improved in milling property in the preparation of the above sensitizer, and a thermal recording medium is provided without impairing the colorability, etc., such as thermal colorability.

Abstract: The invention provides a heat-sensitive recording material, which is highly sensitive, is almost free of staining on the background, and gives a recorded image excellent in stability during storage, by using a finely divided sensitizer dispersion excellent in shelf stability produced in a short time with high volumetric efficiency. The invention relates to a method of producing a sensitizer dispersion, which comprises emulsifying and finely dividing a heat-sensitive recording sensitizer by melting under heating in an aqueous emulsifying dispersant, and then crystallizing the finely divided emulsified dispersion under rapid cooling, wherein the sensitizer is at least one member selected from the group consisting of 1,2-bis(phenoxy)ethane, 1,2-bis(3-methylphenoxy)ethane, 1,2-bis(4-methylphenoxy)ethane, p-benzylbiphenyl, di-p-methylbenzyl oxalate, and ?-naphthyl benzyl ether.

Abstract: The present invention provides a reversible thermosensitive recording medium including a support and a thermosensitive recording layer thereon, in which the thermosensitive recording layer contains an electron-donating coloring compound and an electron-accepting compound, and the thermosensitive recording layer is capable of forming a relatively developed condition and a relatively erased condition depending on at least one of the difference of heating temperatures and the difference of cooling rates following to heating, and in which the electron-accepting compound contains a phenol compound expressed by General Formula (1): where, in the General Formula (1), “l” represents an integer of 1 to 3 and “m” represents an integer of 23 or more.

Abstract: New color developers, new mixture comprising it, its processes for preparation, heat sensitive recording compositions and materials comprising the novel developers and mixtures as well as their uses in heat sensitive recording materials.

Abstract: Storage-stable compositions comprising a colour developer, an anionic dispersant and a thickening agent as well as heat-sensitive recording materials comprising such compositions, a process for its manufacture and its use.

Abstract: The present invention provides a reversible thermosensitive recording medium including: a support, and a reversible thermosensitive recording layer laid on the support, the recording layer containing a reversible thermosensitive composition, wherein the reversible thermosensitive composition forms a relatively color-developed state and a colorless state depending on a difference in a heating temperature and/or a cooling rate after heating by the use of an electron-donating color-forming compound and an electron-accepting compound; a resin component contained in the reversible thermosensitive recording layer is a resin in which a polyol resin having a hydroxyl value within the range of 100 KOHmg/g to 250 KOHmg/g is crosslinked; and as the electron-accepting compound, a urea compound represented by the following General Formula (1) is used, where “n” is an integer of 23 or greater.

Abstract: The present invention provides a reversible thermosensitive recording medium including a support and a thermosensitive recording layer thereon, in which the thermosensitive recording layer comprises an electron-donating coloring compound and an electron-accepting compound, and the thermosensitive recording layer is capable of forming a relatively developed condition and a relatively erased condition depending on at least one of the difference of heating temperatures and the difference of cooling rates following to heating, and in which the electron-accepting compound comprises a phenol compound represented by the General Formula (1): where, in the General Formula (1) “l” represents an integer of 1 to 3, “m” represents an integer of 1 or more, and “n” represents an integer of 7 or more.

Abstract: A reversible thermosensitive recording medium including a substrate, and a thermosensitive layer including an electron donating coloring compound, an electron accepting compound, and a phenol anti-oxidation agent containing one or more sulfur atoms having an alkyl group on one side. In addition, the thermosensitive layer reversibly changes its color tone depending on temperature to reversibly record and erase an image thereon.

Abstract: A reversible thermosensitive recording medium including a substrate, a reversible thermosensitive recording layer and an intermediate layer. The reversible thermosensitive recording layer is configured to reversibly record and erase an image therein and disposed overlying the substrate and includes a binder resin and a reversible thermosensitive coloring composition. The reversible thermosensitive coloring composition includes an electron donating coloring compound and an electron accepting compound. The intermediate layer includes another binder resin and a content of hollow particles having a hollow ratio not less than 70% and a ratio of a maximum particle diameter thereof to a 50% cumulative particle diameter of from 2.0 to 3.0. The reversible thermosensitive recording layer achieves a colored state when heated to a temperature not lower than a melting point thereof, and achieves a discolorization state when heated to a temperature lower than the melting point.

Abstract: There is provided a reversible thermosensitive recording medium including a support, an intermediate layer, and a thermosensitive recording layer which reversibly changes a color thereof depending on a temperature, wherein the thermosensitive recording layer contains an electron-donating coloring compound, and an electron-accepting compound represented by the following general formula 1: where, n is an integer of 23 or more, and wherein the intermediate layer is disposed between the support and the thermosensitive recording layer, and contains hollow particles having a void ratio of 70% or more, a maximum diameter D100 of 5.0 ?m to 10.0 ?m, and a ratio D100/D50 of 2.0 to 3.0 where the ratio D100/D50 is a ratio of the maximum diameter D100 to a 50% cumulative particle diameter D50 of the hollow particles.

Abstract: A reversible thermosensitive coloring material which can reversibly achieve a relatively colored state and a relatively discolored state depending on a temperature to which the coloring material is heated or a cooling speed at which the coloring material is cooled after heated. The coloring material including an electron donating coloring agent; an electron accepting color developer configured to color the coloring agent; and a compound having a Zwitter ion in which a total of charges in a molecule of the compound is zero. A reversible thermosensitive recording material including a substrate and a reversible thermosensitive recording layer, which is located overlying the substrate and which includes the reversible thermosensitive coloring material.

Abstract: A heat-sensitive recording material comprising a support and a heat-sensitive recording layer, the heat-sensitive recording layer comprising a colorless or pale-colored basic dye and a developer, the developer being 4-allyloxy-4?-hydroxydiphenylsulfone, and the heat-sensitive recording layer further comprising a compound represented by formula (I): wherein R1 is an unsubstituted aromatic group, or an aromatic group substituted with at least one member selected from the group consisting of a methyl group and a chlorine atom, and R2 is a divalent organic group.

Abstract: The present invention provides a composition and a recording material made from the composition having an excellent dynamic sensitivity in recording as well as an excellent image stability and, particularly, having excellent resistance for heat and humidity, heat, light, plasticizer and water. The composition and the recording material include the following compounds (1), (2), and (3): wherein R1, R2, R6, R7, R11, and R12 each represents hydrogen or an alkyl group; a1 to a3 each represents an integer of 1-6; n1 to n3 each represents 0, 1 or 2; m1, m4 and m7 each represents 0, 1, 2 or 3; R3, R4, R8, R9, R13 and R14 each represents an alkyl group; m2, m3, m5, m6, m8 and m9 each represents 0, 1 or 2; and Y1 to Y3 each represents CO or NRCO (R represents hydrogen, etc.).

Abstract: Provided is a thermally sensitive recording medium which exhibits high recording sensitivity, high heat resistance of ground color part and excellent preserving stability of images. A thermally sensitive recording medium, comprising a thermally sensitive recording layer containing a colorless or pale colored basic colorless dye and an organic color developing agent as main components on a substrate, wherein said thermally sensitive recording layer contains at least one compound represented by general formula (1) and contains at least one compound selected from the group consisting of 3-{[(phenylamino)carbonyl]amino}benzensulfoneamide represented by formula (2), an ureaurethane compound represented by formula (3) and a copolymer of glysidilmethacrylate and vinyl monomer (average molecular weight is 9000-11000, epoxy equivalent is 300-600 and melting point is 110° C. or less) as a stabilizer.

Abstract: A reversible thermosensitive recording medium including a substrate; and a reversible thermosensitive recording layer located on the substrate and reversibly achieving a relatively colored state and a relatively discolored state depending on the temperature to which the recording layer is heated or the cooling speed at which the recording layer is cooled after heating, wherein the reversible thermosensitive recording layer comprises a polyalkylene glycol compound having a number average molecular weight not less than 2,000 exclusive of polypropylene glycol having a number average molecular weight not greater than 5,000. A reversible thermosensitive recording device, and an image processing method and apparatus using the reversible thermosensitive recording medium are also be provided.

Abstract: A thermosensitive recording material comprising a substrate sheet and a thermosensitive colored image-forming layer formed on at least one surface of the substrate sheet and comprising at least one colorless or light-colored dye precursor and a color-developing agent reactive with the dye precursor upon heating to thereby develop a color, wherein the color-developing agent comprises at least one compound of the formula (I): (wherein R1 represents a member selected from the group consisting of unsubstituted aromatic hydrocarbon groups and substituted aromatic hydrocarbon groups with at least one substituent selected from the group consisting of a methyl group and a chlorine atom, and R2 represents a divalent organic group).

Abstract: A latent image developing system, a novelty kit, and an ink composition for printing latent images on a substrate. The latent image developing system includes a first substrate containing a colorless image deposited on a first surface thereof. A developer component is provided that is reactive with the colorless image to provide a visible image. The developer component is selected from a developer instrument, a developer finger paint, a developer coating on a first surface of a substantially transparent substrate for adhesive attachment to the first substrate, and a combination of one or more of the developer instrument, the developer finger paint, and the developer coating. The latent image developing system optionally includes, an image blocking instrument for concealing at least a portion of the visible image. The image blocking instrument includes a blocking composition applicator and an aqueous mixture of blocking composition and water.