PURPOSE: To improve a shelf life at a high temp. after recording by providing a recording layer consisting of a resin having a specific structure and a quencher on a substrate.
CONSTITUTION: A recording layer consists of a resin having a cyanine dye having an indole ring at the side chain and a quencher. The cyanine dye is expressed by the formula Φ-L=Ψ(X-)m, in which Ψ and Φ denote an indole ring which may be condensated with an aromatic ring, for example, benzene ring, phenanthrene ring, etc., and Φ and Ψ are usually the same. L denotes a connecting group for forming a mono-, di-, tri or tetracarbocyanine dye. X- is anion and m is 0 or 1. The resin is enumerated by an OH-contg. resin, COOH or acid chloride group-contg. resin and NH2-contg. resin. The resin and the dye are bound by direct condensation or condensation with the other connecting component. The quencher is particularly preferably a singlet oxygen quencher and is incorporated at generally 0.05W12mol, more particularly 0.1W1.2mol in 1mol the cyanine dye in the dye-bound resin. The thickness of the recording layer is made usually about 0.03W10μm.
ASAMI SHIGERU
AOI TOSHIKI
TAKAHASHI KAZUO
KUROIWA AKIHIKO
