# Murakami photocure emulsion, exposure time



## mkualii (Aug 1, 2008)

I have a Raynar exposure unit and I'm using Murakami photocure emulsion. My screens take a long time to wash out. Does anyone know how long I should set the time on the exposure unit? Or does anybody know the proper time?


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## BroJames (Jul 8, 2008)

What is your exposure time? Variables would include how you coat, shelf life of the emulsion, how long it was coated before the exposure, possibility of premature exposures, opacity of your printed artwork, washout method, etc.

I've used murakami TXR SBQ emulsion which were marketed here as aquasol TXR by one of the supplier here. If they're the same they should expose from 2 -10 minutes on a typical UV fluorescent units. 2 minutes would be under exposure but you'd get a good wash out. The longer times are from more durable exposures.


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## Alan Buffington (Oct 27, 2010)

Like Angel is asking, need to know more. What mesh? What was your coat technique? Which side of scoop coater, dull or thick? You can find articles for performing a step test on your emulsion at:
www.murakamiscreen.com

Alan Buffington
Murakami Screen USA


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## Alan Buffington (Oct 27, 2010)

Typically 12-18 minutes for a 110 coated 1:1 or 1:2. A lot depends on coating technique, edge used, so a step test is the best method. Draw 11 lines 1 inch apart on the bottom of a coated 110. Tape down a positive you will use on a 110 mesh or any mesh, just know each mesh will have a different time. With the positive taped down well blockout 9 panels with thin chipbaord or very dark black trashbag and expose the first panel for 2 minutes. Now move the cardboard or trashbag to next line, and expose both the first and the second panel for 2 minutes. Keep doing this for all panels. this will give you exposure times on the ten panels from 20-2 minutes. Develop screen, choose the panel during development without any slime on inside and good exposure details or a sharp edge to the exposed imaged areas. If you get slime on all of them cut down coating to 1:1 dull, or even to sharp. These fluo tubes can have difficulty exposing thicker stencils, so if it doesn't work go back and reduce the coating to a thinner coating procedure to obtain exposure times with a step test. Photocure BLU works best on these systems.

Alan
Murakami Screen USA
323-980-0662 ext 118


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