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screen printing => Screen Making => Topic started by: Doug S on August 30, 2016, 08:00:53 PM

Title: Not exposed enough?
Post by: Doug S on August 30, 2016, 08:00:53 PM

Just a curiosity here.  When reclaiming I always start spraying the emulsion off from the shirt side of the screen.  While spraying it off I notice the squeegee side is almost a separate film staying in tact until I hit it with the pressure washer from the squeegee side.  Would this be a sign of underexposure?  I never get staining with a white paper towel during development on the squeegee side and never have issues with break down.

Title: Re: Not exposed enough?
Post by: Frog on August 30, 2016, 08:18:01 PM

Has the emulsion on the squeegee side obviously started to dissolve from the chemistry and then a little scrubbing with a pad or brush?

Title: Re: Not exposed enough?
Post by: Colin on August 30, 2016, 09:00:07 PM

Could also be your cleaning chemical does not like your emulsion.

Title: Re: Not exposed enough?
Post by: Frog on August 30, 2016, 09:40:49 PM

Quote from: Colin on August 30, 2016, 09:00:07 PM

Could also be your cleaning chemical does not like your emulsion.

but that interaction is a primary characteristic of underexposed screens as well.

Title: Re: Not exposed enough?
Post by: Colin on August 30, 2016, 10:45:04 PM

You usually see it there yea.

You can also see it with pure photopolymer emulsions and some stronger cleaning chemicals.

Title: Re: Not exposed enough?
Post by: Doug S on August 31, 2016, 08:39:33 AM

Quote from: Colin on August 30, 2016, 10:45:04 PM

You usually see it there yea.

You can also see it with pure photopolymer emulsions and some stronger cleaning chemicals.

Quote from: Frog on August 30, 2016, 08:18:01 PM

Has the emulsion on the squeegee side obviously started to dissolve from the chemistry and then a little scrubbing with a pad or brush?

This is the cryocoat emulsion.  I'm using a diptank with evirosolve.  I never thought about chemical interaction.  Thanks everyone for the input.