| 摘要 |
PURPOSE:To obtain superior suitability for high-speed recording and resistance to plasticizer and to improve whiteness by using a specific organic metal compound and 4-hydroxy-4'-isopropoxy diphenylsulfone and/or 4-hydroxy-3',4'- tetramethylene diphenylsulfone in combination as a color developer. CONSTITUTION:As a color developer for a thermal recording medium using a color reaction of a colorless or light-colored basic dye and the color developer coming into contact with said dye to produce a color, at least one of organic metal compounds shown by a general formula I, where R represents a satd. or unsatd. aliphatic hydrocarbon residue which may have substituent or an aliphatic hydrocarbon residue having ether linkage, X represents halogen atom, (n) is an integer 1-4, and M is a polyvalent metal having a valence of (m), and 4-hydroxy-4'-isopropoxy diphenylsulfone and/or 4-hydroxy-3',4'-tetramethylene diphenylsulfone are used in combination. The combination ratio is not esp. limited, but it is desirable that the diphenylsulfone derivative is used in the amount of generally 1-2000 pts.wt. and preferably 10-1000 pts.wt. per 100 pts.wt. of the organic metal compound. |
