Journal of Film Preservation - FIAF

Restauración de ondulaciones del sustrato
adhesivo
Cuando se estaciona un material fotográfico
en un ambiente de alta humedad relativa, la
emulsión corre el peligro de dilatarse
excesivamente; el soporte puede encoger;
ciertas partículas de plástico pueden
desprendrese y alojarse irregularmente entre
la emulsión y el soporte. Los negativos que
han sufrido estas alteraciones, en general no
son ya aptos para la duplicación. Se trata en
este artículo de presentar un método
destinado a suprimir las ondulaciones de
negativos fotográficos y de recobrar su
forma original. El método descrito es eficaz
cuando se trata del tratamiento de negativos
conservados en contenedores que permiten
la aeración del material; en cambio es
ineficaz cuando se trata de rescatar
negativos conservados en contenedores
herméticos.
technology has an excellent integrated image (photographs 1 & 2),
making it seem as though it were a fresh negative. This shows that
the above mentioned technology is 100% successful. In the words of
expert witnesses to this work: “[This achievement] resolved the
problem of long-time storage, effectively restoring the integrity and
continuity of the archive. The method is simple, the cost is low, and
the results are excellent. It has created a new restoration approach”.
“Both in pollution-free transplantation technology and in long-time
storage of original negative it holds the world lead.”
Restoration of cellulose acetate-based cut negative film
It is found through experiments and research that the method used for
restoration of wrinkled cellulose nitrate-based cut negative cannot be
applied to restore the wrinkled cellulose acetate-based cut negative.
We should separate and transplant the image layer of acetylcellulose cut
negative with an organic solution; to compare the image layer separated
from acetylcellulose cut negative with the emulsion layer separated from
nitrocellulose cut negative. The following three differences were noted.
Firstly, organic solution separates the image layer together with the
subbed layer, but if the wrinkled section is the image layer and not the
subbed one, how can these two be smoothed out together? Secondly,
another difficult technological problem is how to clear away crystals of
plastic sandwiched between the image and subbed layers. Thirdly, how
to remove white fog from the surface of the emulsion layer? In
connection with this, we have developed one organic solution for
separation of the emulsion layer and another for smoothing out and
cleaning the wrinkled image layer, and in doing so have successfully
resolved the three above-mentioned problems. (Photographs 3& 4)
a. Preparations
1. With the original wrinkled negative make a reversal positive, in
case the attempt at transplantation fails.
2. Compound the restoration solutions. There is one solution for
separating emulsion layer (solution A) and one for smoothing out
and cleaning emulsion layer (solution B).
3. Accepting support. Same as the support used in the restoration of
nitrocellulose cut film.
4. Instruments: 20-27cm enamel pans, volumetric beakers, scissors,
absorbent cotton, optical glass of a size slightly larger than the
negative to be restored, medicinal gloves, enlarging and copying
equipment, etc.
b. Procedure of emulsion layer transplantation
1. Take 100ml of solution A and 500ml of solution B; place them
into two separate enamel pans. Maintain their temperature at 18-24°.
2. Cut out c. 1-2mm from the four edges of the wrinkled negative, so
as to clear away the possible adhesion parts of gelatin layers above
and under the support.
38 Journal of Film Preservation / 58/59 / 1999