FOTOKEMIKA - EFKE
CHARACTERlSTlCS OF
PE PHOTOGRAPHlC PAPERS
A polyethylene layer is applied on both sides of the paper support,
and over the polyethylene layer photographic emulsion is coated. This polyethylene
layer prevents absorption of water and processing chemicals into the support
so the processing takes place only in the emulsion layer. This way the
time required for making photographs is considerably reduced; as well as
the consumption of processing baths and rinsing water. PE photographic
papers are more resistant, stronger, and their dimensional stability is
higher than with the conventional photographic papers. For this reason
they have a wide range qf application possibilitiss. Photographs made on
PE photogaphic papers do not curl, and high gloss of their surface is obtained
by letting them dry freely in the air.
ILLUMINATION OF THE DARKROOM
When handling BROMAL and BROMAL PE photographic papers,
for the illumination of the darkroom we recommend the use of folloving
safelight filters:
- yellow-green ZZ-1 5 for indirect illumination
- yellow-green Z-35 or brown S-34 for direct illumination.
When handling EMAKS and EMAKS PE, EFKEBROM and EFKEBROM
PE, we recommend the use of following safelight filters:
- orange N-1 5, yellow-green Z-1 5 or red C-1 5 for indirect illumination
- orange N-35, yellow-green Z-35 or red C-35 for direct illumination.
With all FOTOKEMIKA safelight filters we recommend the use of 15 W up to
max. 25 W bulbs. The normal distance between the housing with the filter
and photographic materials is 80 cm.
PROCESSING
For developing black-and-white FOTOKEMIKA photographic papers we recommend
the use of efke FR-4 developer or efke FR-16 universal developer.
The developing time for BROMAL and BROMAL PE photographic papers is 2 mins,
and for EMAKS and EMAKS PE 1.5-2 mins. The temperature of the developer
should always be adjusted to 293 K (20C).
Developed photographs are immersed into a stop bath (2% acetic acid)
for about 1 5 s or washed in running vrater for 30 s.
For fixing we recommend the use of efke FF-1 acid fixer (for
about 1 5 mins) or efke FF-2 rapid fixer (for about 8 mins) at the
temperature of 293 K (20C).
Fixed photographs should be washed in running water.
Washing time for photographs made on resin coated support is 5-10 mins
and photographs made on baryta coated support should be washed for about
30 mins.
Photographs made on PE support should be dried freely in the air or
inside driers by flow of warm air at the temperature up to 333 K (60C).
Photographs made on P or K support should be adequately dried in units
for heat-drying.
BROMAL PE photographic paper has been also designed for machine
process at higher temperature - up to 303 K (30C).
STORAGE
Photographic paper should be stored in rooms protected from heat
humidity and harmful vapors. We recommend the following storage conditions:
temperature 277-293 K (4-20C1, relative humidity 50 606.
Opened packages should be kept in dry rooms.
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