| 摘要 |
PROBLEM TO BE SOLVED: To provide a reversible thermochromic compsn. which has stable color-developing and color-fading properties and can meet the requirement for high-speed fading of color by using a specific phenol compd. as an electron- accepting compd. SOLUTION: An electron-donating color-developing compd. and an electron- accepting compd. are used for forming relatively colored and noncolgred states due to the difference in heating temps. and/or in cooling rate after heating. In this invention, a phenol compd. of the formula is used as the electron- accepting compd. In the formula, m and n are each independently an integer of 1-3; X and Y are each a heteroatom-contg. divalent group; R1 is H or alkyl; R2 is a 1-20C divalent hydrocarbon group; R3 is a 2-20C hydrocarbon group; p is an integer of 0-20; r is an integer of 0-3; provided when X is -CONH-, then p and r are both 0 and R1 is not hydrogen. A reversible thermal recording medium is prepd. by forming a recording layer contg. the compsn. as the main ingredient on a substrate. |
