| 摘要 |
PURPOSE:To extend record life by forming on a substrate a recording layer obtained by forming built-up 2-dimensionally oriented monomolecular films of a photochromic compd. exhibiting photochromism dependent on cis-trans isomerization and a monomolecular film-forming material both having affinities to polar and nonpolar solvents. CONSTITUTION:As the photochromic compd. having affinities to polar and nonpolar solvents, compds. each having an unsatd. dobule bond causing cis-trans isomerization, such as azobenzene having an -N=N- structure and indigo and thioindigo having a -C=C- structure, substd. by an alkyl chain at the structure except the unsatd. double bond is used. A mixture of the photochromic material and the monomolecular film-forming material both affinitive to both type solvents is formed on the substrate 1 as the built-up 2-dimensionally oriented monomolecular films to form the recording layer 2, and a protective film 3 is formed on this layer 2. In the built-up monomolecular films 2a'2c, the photochromic compd. 4 and the monomolecular film-foming material 5 are combined in a mixed state, thus permitting the obtained photorecording medium to be extended in record life. |
