Thermally sensitive recording medium

摘要

A thermally sensitive recording medium having sufficient color developing density and which develops russet or wine red color. The recording medium incorporates a dye precursor which includes at least one red color developing leuco dye having a maximum absorption wavelength of 480 to 570 nm and at least one black color developing leuco dye with maximum absorption wavelengths at 420 to 480 nm and 550 to 640 nm. The color difference a* value of developed image of said thermally sensitive recording medium, measured according to JIS-Z-8729 is within the region of 0 to 50 and b* value is within the region of -15 to 10.