Patent ID: 8236728

Claim:
A heat-sensitive transfer sheet comprising a base film, a dye layer formed over one surface of the base film and containing a heat-transferable dye and a resin, and a heat-resistant lubricating layer formed over the other surface of the base film and containing a lubricant and a resin, wherein the heat-resistant lubricating layer contains a phosphate ester represented by the following formula (I) and at least one of a polyvalent metal salt of an alkylcarboxylic acid and a phosphate ester polyvalent metal salt as the lubricant, and the maximum value of the following characteristic X-ray intensities is at least 5 times the minimum value thereof: characteristic X-ray intensities obtained by radiating an electron beam which is accelerated to 20 kV and has a beam diameter of 1 μm or less onto plural positions of the heat-sensitive transfer sheet from the heat-resistant lubricating layer side of this sheet, and measuring the resultant characteristic X-rays originating from the K-line of the phosphorus element in the heat-resistant lubricating layer by means of an energy dispersive X-ray spectrometer: wherein M represents a hydrogen atom or a monovalent metal, R 1 represents a hydrogen atom, a monovalent metal, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an aromatic group which may have a substituent, and R 2 represents an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an aromatic group which may have a substituent.