| 摘要 |
PURPOSE:To provide a thermal recording paper having both position readability through irradiation with UV rays and optical readability in a near infrared region, by incorporating a near infrared light-absorbing leuco dye as a basic colorless dye into a thermal color forming layer, and incorporating a specified fluorescent dye into an overcoat layer. CONSTITUTION:A near infrared light-absorbing leuco dye is incorporated as a basic colorless dye into a thermal color forming layer, and a fluorescent dye having a maximum peak in a fluorescent spectrum generated on irradiation with UV rays of 450-700nm is incorporated into an overcoat layer. The leuco dye is a dye capable of efficiently absorbing light in a near infrared region (particularly, 700-1,500nm) upon color formation through a heat-melting reaction with an organic color developer. Examples of such a leuco dye include fluorene leuco dyes and fluoran leuco dyes The fluorescent dye may be a dye based on anthraquinone, indigo, triphenylmethane, thiazine, thiazole or the like. |
