A sublimation thermal transfer sheet and combination of a sublimation thermal transfer sheet and a transfer receiving article that meet the demand for increase in the density of a color image to be formed, that prevent decrease in the adhesiveness of a protective layer optionally formed on the color image, and that also have superior light resistance. In a sublimation thermal transfer sheet including a substrate and yellow, magenta, and cyan colorant layers provided on one surface of the substrate, the yellow and the above magenta colorant layers each contain a predetermined amount of a high- sublimable dye having a molar absorption coefficient of not less than 50000 and a molecular weight of not more than 650, and the cyan colorant layer contains a predetermined amount of a high- sublimable dye having a molar absorption coefficient of not less than 20000 and a molecular weight of not more than 420.

Provided are a sublimation thermal transfer sheet and a combination of a sublimation thermal transfer sheet and a transfer receiving article that meet the demand for increase in the density of a color image to be formed, that prevent decrease in the adhesiveness of a protective layer optionally formed on the color image.

In a sublimation thermal transfer sheet including a substrate and yellow, magenta, and cyan colorant layers provided on one surface of the substrate, the yellow, magenta, and cyan colorant layers each contain at least a binder resin and a sublimable dye having a molar absorption coefficient of not less than 50000 and a molecular weight of not more than 650, and the average of the mass ratios of the respective binder resins and sublimable dyes (sublimable dye/binder resin) in the yellow, magenta, and cyan colorant layers is not less than 0.7.

A method of producing a security document includes the steps of producing a first part of a color image by color laser marking a security document precursor; and producing a second part of the color image by a second imaging technique different from laser marking. The resulting security document is more difficult to falsify.

In a thermal transfer sheet in which a transfer layer is provided on a substrate, the transfer layer has a layered structure in which a receiving layer, an intermediate layer, and a masking layer are layered in this order from the side of the substrate, the receiving layer is a solvent-based receiving layer containing a solvent-based resin and a silicone oil, the intermediate layer is a water-based intermediate layer containing a water-based resin, and the masking layer is a solvent-based masking layer containing a solvent-based resin and a colorant.

A thermal transfer recording sheet set includes an image-receiving sheet that includes an image-receiving layer containing a compound represented by general formula (1) or (2) and an ink sheet that includes a yellow coloring material layer containing a particular dye and a cyan coloring material layer containing a particular dye.

A color laser markable article includes at least a first and a second laser markable layer including, respectively, a first infrared dye IR-1 having an absorption maximum in the infrared region .sub.max(IR-1) and a second infrared dye IR-2 having an absorption maximum in the infrared region .sub.max(IR-2), characterized in that the color laser markable layers further include a Diffusion Hindered Molecular Assembly (DHMA) which contains a leuco dye.

A laser markable composition includes (a) an aqueous medium; (b) a leuco dye; (c) an optothermal converting agent; and (d) a color developing agent, characterized in that the color developing agent is a polymer particle capable of forming an acid upon exposure to heat.

A method for forming a print obtained by transferring a transfer layer from which a removal region has been accurately removed onto a transfer receiving article and a method for peeling off a transfer layer by which a removal region of the transfer layer can be accurately removed. The method for forming a print comprises, by using a transfer film in which a transfer layer is provided on one surface of a support, a thermal transfer sheet in which a peel-off layer is provided on one surface of a substrate, and a transfer receiving article, a step of removing a removal region of the transfer layer of the transfer film by means of the peel-off layer of the thermal transfer sheet and a step of transferring the transfer layer from which the removal region has been removed onto the transfer receiving article.

A sublimation thermal transfer sheet having first, second, and third dye layers frame sequentially provided on a surface of a substrate in this order, and a back-face layer provided on another surface of the substrate. The first, second, and third dye layers contain an each individual sublimable dye and an each individual binder resin. One of the first and second dye layers further contains a releasing agent selected from a first group consisting of silicone oils, silicone-modified resins and phosphoric esters, and another dye layer further contains either one or both of at least a releasing agent selected from the first group and a cellulosic resin. The third dye layer (1) contains no releasing agent of the first group, or (2) contains the releasing agent at an amount of not more than 0.3% by weight based on the total weight of the solid content of the third dye layer.

In a thermal transfer recording sheet including a base material and a colorant layer, the colorant layer includes a yellow dye layer containing a yellow dye, a magenta dye layer containing a magenta dye, and a cyan dye layer containing a cyan dye, and the cyan dye includes a compound represented by Formula (Ia) or Formula (Ib):

##STR00001##

where R.sub.1 to R.sub.7 are substituents, X.sup. is an anion, and the compound of Formula (Ib) has at least one anionic substituent.