FAQ

Emulsion FAQ List

1. Delamination during washout
   
   
2. Loss of fine detail
   
   
3. Image area difficult to washout
   
   
4. Peel off and breakdown in press run
   
   
5. Pinholes
   
   
6. Saw tooth
   
   
7. "Open" areas in stencil not printing

p:Delamination during washout

a:
1. Under exposure;
2. Emulsion not sensitized completely;
3. Sensitizing powder deteriorated.

P:Loss of fine detail

a:
1. Over exposure;
2. Uneven coating----have a check on screen tension;
3. Refraction---dyed mesh is preferred for fine work;
4. Improper vacuum----perfect contact is wanted for positive film.

p;Image area difficult to washout

a:
1. Extremely over exposure.
2. Drying temperature too high, no higher than 40 Centigrade;
3. Pre-exposure during drying; processing should be under safety light or muted light;
4. Coated stencil has been stored too long.

p:Peel off and breakdown in press run

a:
1. Screen not tensioned properly;
2. Under exposure;
3. Improper process in prepress;

p:Pinholes

a:
1. Some dust or dirt on positive or glass plate;
2. Emulsion being polluted, keep the room clean.

p:Saw tooth

a:
1. Mesh too coarse or not dyed, dyed mesh is expected if over 196 dpi (77 dpc);
2. Improper wash pressure or time, the wetting time should no longer than 60s;

p:"Open" areas in stencil not printing

a:
1. Improper washout----make sure a complete washout;
2. Humidity too high after washout