emulsion not curing

[dijaedi]

Hi guys

I have a weird problem. I've mixed a 9:1 ratio of emulsion and synthesizer, let sit for two hours and then coat 1/1. The screens have been degreased. I've done a step test to figure out the time and the images are washing out perfect. My problem is that after I did a couple of test prints I went to wash out the ink and all the emulsion washed out with it. I tried letting the screen sit in the sun for 30+ minutes after washing out the image hoping that it will cure the emulsion but still got the same result. As soon as the screen touches water the emulsion starts getting slimey and comes off. Is this a problem with my mix? Do I need to add more synthesizer?

[Catspit Productions]

That is very odd indeed. I am unsure why that may be as I do not know what type of emulsion you are using. If it were a known dual cure resistant to water based inks I would have no guess.

Actually I still have no guess. Unless since you are only doing a couple of text prints the emulsion is not fully cured due to insufficient sensitizer. Are you mixing in the correct amount of sensitizer as directed by the vendor? It could be that it does not have enough sensitizer, which may be why it is washing out easily.

And I am unfamiliar with water based inks you can use water to clean off too. I never used that type of water based ink.

[dijaedi]

Thanks for your reply. The shop just gave me a quart of emulsion and a quart of liquid synthesizer and told me to mix it 9:1. I've just been eyeballing my mixture and trying to get as close to a 9:1 ratio as possible. The emulsion is made by a Thai company called Twins and the ink is made by Nika. Anyway I found a factory here today that sell photopolymer emulsion from China. I'm going to try that emulsion and see if it works any better. I'm in Cambodia and it's been pretty hard to find supplies. I'm still curious though, if I didn't add enough synthesizer and the emulsion didn't cure, what would happen if I add too much synthesizer?

[Catspit Productions]

You're very welcome. LOL... you know I don’t know. Maybe it would become faster in speed for exposure times or it may become brittle. Hard to say not being a chemist. But normally we add the entire bottle of sensitizer the vendor gives us into the amount of emulsion sold with it. It’s not worth trying to mix it in smaller quantities. That may be the issue there.

Either try a photopolymer as you suggested or mix the entire quart of emulsion with all of the contents of the sensitizer bottle at one time to get the proper mix.

I know it can be hard to fins supplies in certain areas of the world. Good luck and let us know how it works out.