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Gedakop-System FAQ

1. Copying
Depending on the UV-exposure unit 50 to 120 seconds.
2. Developing
With cold, running water. Typeface (graphics) must be perfectly clear visible after 30 to 60 seconds.

Potential Problems, their causes and problem solving:

a) Photo resist layer dissolves completely
Cause: heavy underexposure, i.e. exposure time is calculated much too short
Help: increase exposure time by at least 50%.

b) Photo resist layer spongy, dissolves partly
Cause: slight underexposure
Help: increase exposure time by 20 to 30%

c) Typeface (graphics) not or very faintly visible, Fine lines and screen raster points not visible
Cause: overexposure
Help: decrease exposure time

d) Plate too old = over 12 month
Check date on packaging or backside of the plate. Coding: ex. 200371 = Produced in July 2003

e) Too long exposure to daylight
Plate was exposed to daylight too long; photo resist layer lost it's greenish color and
appears rather bluish. The plate cannot be developed properly anymore.

3. Drying
Mandatory: First let the water drain off, then lay newspaper flat and rub (blot) the entire plate gently. Only after that dry with hot air or heating plate.

a) Newspaper sticks to plate
Cause: Paper was left too long on the wet photoplate and/or exposure time too short (photo resist layer was not hardened properly)
4. Dyeing
Apply dye in circular motion during 30 seconds. Let the dye work in for max. another 30 seconds. Remove surplus dye with clean dry cloth completely.

a) Dye penetrated photo resist layer
1. Dye was applied with too much pressure
2. Application of dye too long
3. Dye worked in too long
4. Color was not entirely removed before stripping off the resist layer
5. Resist layer was still wet
6. Athmospheric Humidity over 60% (very warm and humid weather)

b) Typeface (graphics) not entirely dyed
1. Too little dye applied
2. Resist layer wan not dissolved properly by too short dyeing or not applying the dye with circular motion
3. Pore's absorbtion ability bad because plate was not rubbed properly with newspaper (see 3.)
4. Pore's absorbtion ability poor because of material defect
5. Negative Typeface (Background dyed, Typeface silver); Film / Laserfoil's density not high enough.
Help: Reheat the plate slightly, color again with sufficient dye.
5. Stripping
Stip the panel with GEDA-Stripper by using a sponge or a clean cloth.

a) Small dots of dye are visible
Cause: Water and dye got mixed (for example by saliva emitted by talking during dyeing)
6. Sealing
During 40 minutes in preheated 95░C / 203░F hot water.

a) Loss of dye
1. Panels were put in the hot water before it reached it's mandatory temperature
2. Average temperature below 95░C / 203░F
3. Sealing time too short (under 40 minutes)
4. Missing seal-salt in the water
5. Salted water too old (over 6 month)

Please refer to the separatley available brochure "sealing"

GEDACOLOR AG, Feldmattstrasse 34, CH-6032 Emmen/Waldibrücke, Switzerland
Telefon +41 (0)41 268 83 31, Fax +41 (0)41 268 83 32, Mail