Hi
MG Chemicals now sells a "Negative Photoresist Film" (product #416-
DFR5) that I believe may be Riston.
I have tried it several times now with mediocre results. The
traces turn out good when they turn out. The problem I'm getting is
actually getting the film to stick to the board uniformly before
exposure.
Someone suggested using water between the board and the film to
allow rolling of any bubbles out from underneath with your thumb
after positioning, then drying it in an oven at about 200 degrees for
10 min to get it to stick.
They were right, it worked great...until I tried to dry it. Small
mutations formed, sometimes in the form of lines, sometimes what look
like small blobs. They aren't bubbles per se, but somehow there are
areas of the film that appear to stick to the board at a deeper level
than the surrounding film, or maybe they are melting and deforming.
The manufacturer recommends using a laminator to apply the film,
which I tried initially, but it appears to have the same problem. My
laminator is adjustable heat, and I've tried from hi to low with
similar results. I haven't as yet put the board between any
protective sheets when laminating like you might to laminate paper
items...I'm going to try that next (the manufacturer never
specifically said to do it).
Here are their instructions:
http://www.mgchemicals.com/techsupport/416dfr_inst.html I clean the board ahead of time with steel wool, alcohol and
acetone. I am using clean gloves throughout.
Can anyone help me with any tricks to get this stuff to adhere
uniformly?
Thank you so much in advance!
-Josh