| 摘要 |
717,926. Photographic backing papers. KODAK, Ltd. Sept. 21, 1951 [Sept, 27, 1950], No. 22179/51. Class 98(1) [Also in Group VIII] A backing paper having an overall thickness of less than 0.004 inch comprises a sheet of paper having a black pigment coating on one side and a lighter coloured pigment coating on the other. Typically one side of a black Kraft paper of thickness 0.0026-0.0030 inch is coated with a water-containing alcoholic dispersion in zein of a carbon black pigment and on the other side successively with similar zein dispersions of white and yellow or light 'blue pigments, the coating being effected by a partially immersed rotatable roller having a large number of minute cavities in its surface. Printed matter, e.g. exposure numbers, is produced on the light pigment side using inks including zein or a reducing agent to prevent spoiling of the emulsion due to contact with the inkprinted symbols. Alternatively a yellow paper- Kraft paper or a dyed titanium oxide-filled sulphite paper-is coated on one side with a carbon black pigment zein dispersion, ink-printed on the uncoated side, and overcoated on this side with zein. Instead of zein, ethyl cellulose or polystyrene may be used. and the solvents may be anhydrous and comprise ethyl alcohol with either ethylene chloride or methyl ethyl lactone. Specification 23,299/01, [Class 98]. is referred to. |
