Journal of Film Preservation - FIAF

Wrinkled Emulsion Layer: Restoration by
Transplanting to the Negative
Technical Column / Chronique
technique / Columna técnica
Xu Jianhe and Ge Xiangbei
When photographic material is placed in an environment where the
relative humidity is unusually high, its emulsion layer may absorb a large
quantity of moisture and swell excessively; its support may shrink from
decomposition; or the plastics may separate out unevenly in the form of
crystals and remain in the interface between emulsion layer and support.
All of the above may cause a wrinkling of the emulsion layer.
Macroscopically there appear peaks and valleys. Such a negative is
generally no longer capable of printing a photograph.
Now we introduce a method of clearing up the wrinkles on a
photographic negative and of restoring its original appearance. Here we
must point out that the following method is effective only for cut
negative film that has been stored over a long period in an unsealed
state. For cine film materials and cine film copies stored in metal
containers, or for negatives stored in a sealed state, the following method
is not generally effective. This is because, when an image material is
stored in a sealed state for a long period, the gelatin in its emulsion layer
is attacked by the decomposition products of the support and becomes
seriously degraded. Then the emulsion layer turns readily soluble in
both acidic and alkaline solutions. Thus the loss may be irretrievable.
Restoration of cellulose nitrate negative
Whether a wrinkled image layer of nitrocellulose-base cut negative film
can be successfully transplanted or not depends largely on whether the
gelatin layer has maintained its toughness. The best method of judging
this is to moisten the edge of a wrinkled emulsion layer with a piece of
damp absorbent cotton, and to observe whether or not the gelatin has
dissolved. If the emulsion layer only swells, but does not dissolve, and
maintains its toughness, then it can be transplanted successfully.
a. Preparations
1. Take the wrinkled negative to print an enlargement. In cases where
the attempt of transplantation has failed, then this photograph could
be preserved as a substitute of the original negative.
2. Preparations of accepting support. From a subbed cellulose acetate
support cut out a piece, a little larger than the wrinkled negative, to
use as the accepting support. If such a material is not available, take
a fresh black-and-white negative, have it fully fixed, washed and
dried; it is then ready for use.
3. Compound the image layer separation solution.
4. Instruments for transplantation: Vessel for negative transplantation
solution, scissors, working table with transmitted light source, etc.
36 Journal of Film Preservation / 58/59 / 1999