# Emulsion washing away!



## Grumpyvulture (Mar 28, 2007)

Hi everyone,

Hope someone can help, i've only been doing this a few weeks and am having many problems!

For example, tonight I exposed a screen (43T) with Proclaim emulsion. I use one coat squeegee side, two coats print side. I have 2 X 500W lights to burn about 40' height and with the transparancies i'm using have exposed successfully before with 8 mins of light.

I started to wash the screen out (normal household pressure with a shower head) and the image was already a different colour than the rest of the exposed emulsion. A few minutes later and the image was starting to wash out OK - great I thought. Shortly after though, was when things started to go downhill!

Basically, even before the image had completely washed out the surrounding emulsion just started to wash off in huge strips. After a while it had basically all gone!

Its almost like it was totally underexposed but it had changed colour and seemed OK as i started to wash it. 

I should mention that I had previously reclaimed this screen with an ink remover for waterbased ghosting, but I had rinsed it off (and de-greased it). Would this have stopped the emulsion taking? Should I have pressure washed the ink remover?

Any help much appreciated, as if I wasn't having enough problems printing now I can't even get the screens to work!  


Thanks

Mark


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## aust1025 (Mar 1, 2007)

Sounds like you need to degrease your screen before you coat it with emulsion and you should only need one coat by the way. Also it sounds like you need a bit longer exposure.
Here is a tip that i put up on my site that i use to get good exposures.
austindigi.com/scrn-prnt-tips.htm


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## ieaturheart (Apr 2, 2007)

aust1025 said:


> Sounds like you need to degrease your screen before you coat it with emulsion and you should only need one coat by the way. Also it sounds like you need a bit longer exposure.
> Here is a tip that i put up on my site that i use to get good exposures.
> austindigi.com/scrn-prnt-tips.htm


 
Dave just watched your video thanks a super lot for the advice. It helped me to picture the unit from what i have been planning in my mind. thanks again



-austin


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## Grumpyvulture (Mar 28, 2007)

Thanks for the advice Dave, i'll try that.

So you think I only need one coat of emulsion either side? Will that be enough?


Thanks

Mark


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## jimhack3 (Jan 23, 2007)

One coat should be enough, "IF" you expose the screen long enough so that It wont break down when washing out, or screening. Honestly, I used the two coats print and one coat on the bottom side. Worked fine.

Increase your exposure time and degrease the **** out of the screen. Some people dry the screen with a box fan, pointed directly towards the screen, but often times dust and lint can blow particles on the screen and dry in the screen, if you do that, make sure the fan, and fan housing are clean.

I used dual cure emulsion. The pink stuff I think it was ulano brand, or something that sounds like that, and never really had any problems with it. I've never heard of the product that you mentioned. How old is It. was It stored properly?

degrease the bajesus outta the screen though, and always dry thoroughly before coating, and between coatings.

Goood Luck,
Jim


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## Grumpyvulture (Mar 28, 2007)

Cheers for that,

With regards to the emulsion its pretty much brand new - was only sensitized on Monday. It came with my kit and the instructions 'say' Proclaim, but i'm not sure that it is, for example the instructions say its green when sensitized but mines yellow! I'm beginning to wonder if the stuff i've been supplied with is really of that high a quality......  

Before I have used 2 coats front and 1 back - like you say, but even then when I was washing off I noticed the edges go a bit 'ragged' if you know what I mean.

Could that also be a symptom of underexposure? How long would you say it should take to wash the image out?


Mark


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## aust1025 (Mar 1, 2007)

As far as double coating your print side, you can do that if you want, i just did a run of 400 shirts with a screen that had only 1 coat on each side.

Jim is right if you expose properly you'll have no problems, i think i had one pinhole after running all those shirts.


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## aust1025 (Mar 1, 2007)

ieaturheart said:


> Dave just watched your video thanks a super lot for the advice. It helped me to picture the unit from what i have been planning in my mind. thanks again
> 
> 
> 
> -austin


Just have to say that is not me in the video, lol, im a bit younger.
The guy in the video is *rogerjennings* he has a whole series on youtube.com.


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## ieaturheart (Apr 2, 2007)

aust1025 said:


> Just have to say that is not me in the video, lol, im a bit younger.
> The guy in the video is *rogerjennings* he has a whole series on youtube.com.


 
lol i didnt know who it was but it was helpful. and no matter how old (or in my case young) you are we seem to love all here. 


-austin


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## Grumpyvulture (Mar 28, 2007)

OK, time for an update - still problems!

I tried the dime (or in my case 10p!) trick tonight with an exposure of 10 minutes. This is waaay above what Ulano (they make Proclaim) recommend for 3 coats, or indeed any other amount of coats. Yet still the surface emulsion washed away! It seems to hold up OK for a while then it all just runs away, you can then even scrape it off with your fingers!

I'm assuming this means its underexposed still? How much longer should I leave it? I'm using 2 500W halogens and Ulano say it should be something like 140 seconds, so 10 minutes seems to be way over.

All this was on a new, totally degreased screen. 

So far i've only had one screen that turned out anywhere near properly, how long did it take you guys to figure it out?

Its costing me a fortune in emulsion!


Mark


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## Fluid (Jun 20, 2005)

try 15 and see if this works. Sounds like your going to need to test a bit until you get it right.
Since your using a hame made exposure unit its hard to go by the manufacturer specs.


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## jimhack3 (Jan 23, 2007)

Grumpyvulture said:


> I tried the dime (or in my case 10p!) trick tonight with an exposure of 10 minutes. This is waaay above what Ulano (they make Proclaim) recommend for 3 coats, or indeed any other amount of coats. Yet still the surface emulsion washed away! It


Hey GP,

I' ve never heard of the dime trick. I built my own exposure unit, and I understand that you've built yours also. Tell me, when you wash out the screen, did any of "your image" wash out, or did the entire sheet of emulsion wash off without seeing your image?

In your homemade exposure image, how close is your image to your light source?
I am about 9" inches from my light source, and it takes me 11.5 mins to expose a screen. properly, using flouresent bulbs. I found this time through trial and error. I used to expose my images using the sun, for 1.5 mins.

Increase your time like the abov member has said. What puzzles me is that you said that you've already exposed a screen correctly using your process, and when duplicating that process, you've acheived various results. 

Let me know how the increased exposure time works out.

Good Luck,
Jim


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## Grumpyvulture (Mar 28, 2007)

Hey Jim,

This is whats confusing me. I had various trial and error goes when I first got it (which I expected) until I got a decent screen. That was with an 8 minute exposure using 4 coats (2and 2). So I figured that would be my benchmark from now on.

Now i'm in the position where I appear to be back to square one again and I don't know why. When I expose an image you can see that the emulsion is a different colour where the image has been.

The bit I can't understand is that after 10 minutes with an image on it, the emulsion under the image has started to go off and becomes difficult to wash out (its obviously getting slightly exposed in that time) but the remainder of the emulsion (which has been fully exposed) washes off also!

I'm using 2 part emulsion with a sensitizer, but i'm only making up a 1/4 of it at a time, would this be caused if I have the sensitizer mix wrong? The previous successful screen I had was with a seperate mix.

Theres a lot to this, isn't there? Every day is a school day!!  

Mark


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## jimhack3 (Jan 23, 2007)

> I'm using 2 part emulsion with a sensitizer, but i'm only making up a 1/4 of it at a time, would this be caused if I have the sensitizer mix wrong? The previous


GV,

Are mixing your own emulsion. I think that you should purchase a pre-mixed emulsion, If you are not already, and use that instead. You bought a screen-printing kit that contained the emulsion that you are using...right?

I would go to a screen-printing supply store, and get some of the dual cure ulano emulsion. Ulano QTX Pure Photopolymer Emulsion - Blick Art Materials
I've used that since day one, and have not had any problems with It. Ulano - Screen Printing Stencil Products Emulsions Capillary Inkjet Indirect Film

What are you using to coat your screens? Scoop coater/ cardboard, etc? What are you using to degrease your screens. Are the the screens thoroughly dry before exposure? are you drying the coated screens with the print side up?

When coating are you making sure that the emulsion is penetrating the mesh, by slowly, and evenly, with a little pressure on the screen, sliding your scoop coater from the bottom of the screen to the top?

This book will save you time and money: "Screen-Printing for Fun and Profit". A "must have" for ALL screen-printers rookies, and veterans.

Let me know how it works out, OK?


Kind Regards,
Jim


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## JeridHill (Feb 8, 2006)

I don't believe degreasing is your problem, because if it were, it wouldn't coat properly when you were applying your emulsion.

If you were able to get good exposures before and you didn't change anything, then the problem is with your emulsion. If you never were able to get good screens, then like it was already mentioned, increase your exposure time.

Your emulsion does expire and will effect your burn time. You can burn for 1/2 hour with bad emulsion and still get a washout of the image. If you use a mix emulsion, always write the date you mixed it on the label. If you have a refrigerator, it would be good to keep your emulsion in there, it will extend the life.

One last thing, the more coats of emulsion you have on your screen, the longer the burn times. So depending on how you want to coat your screens for any given job, it would be good to go through extensive testing to see what times work with your setup and your various coating methods.

Good Luck.


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## Grumpyvulture (Mar 28, 2007)

Jim,

Yeah i'm mixing my own emulsion, its what came with the kit - as did the degreaser and the screen reclaim, none of which appears to be particularly effective!

There are some photocopied instructions with the emulsion that says its Ulano Proclaim, but its not the colour that Ulano say it is so I really don't know!

Think i'm better off buying better stuff from scratch.

Mark


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## jimhack3 (Jan 23, 2007)

GV,

I think that you're right. After you master coating and screen exposure, then I would try mixing the emulsion. But I would first get a pre-mixed emulsion.

Good luck,
Jim


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