| 摘要 |
In the prodn. of a photographic base of paper with a plastics coating on one or both sides, the front is subjected to oxidative pretreatment, coated with a hydrophilic subbing coat for photographic emulsions and dried. The novelty is that the dried subbing coat is treated with a h.f. corona before the photographic emulsion is applied. Pref., after corona treatment, the treated surface is not brought into contact with machine rolls before applying the emulsion; corona treatment is carried out with a distance of 2-3 mm between the electrode and earth roll, an applied potential of 10-25 kV and a frequency of 10-35 kHz; and the plastics coating is applied by melt extrusion. Pref. the plastics coating is based on polyethylene; and the subbing coat on gelatin.
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