抄録
The purified sheets of the cellophane are dyed with some selected dyes. By dyeing the maximum wave length of these spectra of dyes is shifted to red side, as compared to these of aqueous solution. The dyes are classified into three groups, according to the deformation of the absorption curves of the dyed sheets by the dyeing and dry heating. (a) By the dyeing the new absorption, which clased after heating, is developed to red side of the maximum wave length, and consequently the color change is observed. (b) The same new absorption is shown, but the deformatian of the curve can not be observed by heating. (c) After dyeing no such deformation of curve is shown, except the shift of the maximum wave length and the change of absorption coefficient.
In the case of the dyes of group (a), Azoorseillin and Benzoazurine G, which are substituted by OH groups at the ortho positions of both azolinkages, the color change is greatly improved by treatment with CuSO4 solution. The above new absorption reaches the peak of the vissible region by this treatment without deformation by heating. The new absorption of the dye of group (b), Bril. Purpurine lOB which has no OH group, is not decreased by heating or not affected by Cu treatment. In the case of the group (c), Congo Red, Benzopurpurine 4B, Congo Corinth G, B and Azo Violet, containing some dyes that are substituted by a OH group at the ortho position of azo linkage, too new absorption under the dyeing, heating or Cu treatment are observed.
