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CAPILLEX
FILMS
Stencil
film washes off mesh
- under exposed
- poor degreasing
- insufficiently
roughened mesh
- film applied
to too fine a mesh
Ragged edges
- Capillex
applied to too coarse a mesh
- under exposed
Fine detail
filling in
- over exposed
- poor contact
between positive and stencil film during exposure
- film dried
with excessive heat
- tencil
stored too long before exposure
- positive
not opaque enough
Pinholes
- dust between
glass/positive/stencil
- dust trapped
between stencil film and mesh during laminating
Poor adhesion
- under exposed
- Poor degreasing
- insufficient
roughening of mesh
Patchy stencil
- poor mounting
technique
- excessive
time lapse between squeegeeing off excess water
- film laminated
on uneven surface
Difficult
washout
- over exposed
- film dried
using excessive heat
- positive
not opaque enough
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DIRECT
EMULSIONS
Sawtoothing
- mesh too
coarse, finer detail requires fine mesh
- incorrect
washout, do not use excessive spray
Exposed
emulsion washes off mesh
- under exposure
- not enough
sensitizer or poor dispersion in the emulsion
- insufficiently
roughened or degreased mesh
Fine detail
filling in
- over exposed
- uneven coating
of emulsion
- uneven contact
between positive and emulsion
- positive
not opaque enough
Premature
stencil breakdown
- mesh not
stretched tightly enough
- under exposed,
emulsion not fully hardened
Pinholes
- dust on
glass or positive
- contamination
in emulsion: work in clean area and replace lid on emulsion
when not in use
- stencil
washout carried out for too long or use of too strong
washout pressure
Scumming
- poor washout:
ensure that the image is totally cleared
- inadequate
blotting out after washout -
- screen allowed
to stand vertically when just washed out: dry horizontally
Image does
not wash out at all
- excessive
over exposure
- coated screen
dried in excessive heat (max. 30¼C or 86¼F)
- coated life
of screen expired: do not store more than 3 months at
room temperature
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