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Datak negative Resist Success

2004-01-09 by ednspace

Thanks to all who answered questions earlier I finally have made some 
success with Negative photo resist method.  After about a month of 
trial and errors I have two nicely etched boards.

Points I changed were:
Better UV light the recommended (ER-2000)
Longer drying times after coating blank with the resist
Shorter developing times.
Better negative now using overhead type laser copy instead of oil 
brushed tracing paper.

Now I just need to get some new developer since I have wasted so much 
of what I had and probably a little bake oven to dry the emulsion 
both after I coat and before I etch.

The only problem I am having is that the resist comes very close to 
dissolving in the etchent before the rest of the board is etched 
away. Are there other etchents that may be more suitably matched to 
this resist or should I just concentrate on drying it very well 
before etching and after the developing.

Using ferric chloride with etch times of about 8min warm in bubbles

Again thanks so much to all who offered pointers and helped,
this is a great list, and wonderful to know there are others out 
there working through similar issues.

Finally I can make something again :)
ED

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