| 摘要 |
PURPOSE:To obtain a thermal recording type label having a high reliability and capable of reading its color pictures with a protective layer by a semiconductor lasers by using a specific thiofluoran compound as a leuco dye. CONSTITUTION:An adhesive layer is provided on one side of a supporter, and a thermal color forming layer containing the following leuco dye and a developer is provided on the other side of the supporter and a protective layer is provided on the thermal color forming layer to obtain a desired thermal recording type label. The leuco dye contains one or two or more selected from thiofluoran compounds of the formulas I and II(where R1, R2, R3, and R4 are each a C1-C8 straight or branched chain alkyl or cycloalkyl differently or identically). The protective layer is provided in order to enhance the reliability of color picture, e.g., oil resistance, solvent resistance, plasticizer resistance, etc., and is made of a water-soluble resin, latexes, etc. |
