# advice needed with Ulano Proclaim emulsion



## Inkabilly (Sep 12, 2010)

Hello,

We seem to have developed a problem with our emulsion. We are new to this, and our first batch of screens worked out fine, but now, using the same exposure process, our second batch of emulsion seems to be acting as if it is under-exposed, it's going sticky on both sides of the screen after about 5 prints (using water-based ink). 

We are using 32T & 43T screens, 1000w Halogen light at 20" and Ulano Proclaim (Diazo) emulsion. We left the screens overnight to dry (we live in the UK so humidity shouldn't be a problem?) Our optimum exposure time was around 10 minutes (depending on amount of detail in designs). The emulsion is changing colour and giving us a great, crisp image and the emulsion is washing out of the design well. 

The second batch of sensitizer was delivered in a white plastic bottle, rather than a metal one like the first - is it possible that the sensitizer has suffered from light exposure? This is the only change in circumstance that we can think of - or are we missing something?

Thanks in advance!


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## Vizual Voice (Feb 1, 2008)

I used proclaim almost exclusively for about a year (then switched to Lawson's version of it which is pretty much identical as best I can tell). As far as I can remember the sensitizer has always come in a brown plastic bottle, not a white one. I don't know if the diazo is light sensitive until it's wetted or not, but that may be a factor. I supposed it's also possible that you got a bad batch of sensitizer.

How old is the emulsion? Did you mix it a long time ago or is it relatively fresh. I find that I get about 3 months shelf life with no change and almost another month if I really push it and don't try to do any fine line work with it. After it "expires", it tends to act like it's underexposed no matter how much UV you hit it with and will blow out with the slightest amount of pressure when you wash it out.

I'd take a coated screen and perform a test with something that will totally block the light (black vinyl or electrical tape works well, or you can even tape a coin or piece of aluminum foil to the screen). Try that instead of one of your usual positives and rather than your exposure unit, take it outside into the sun for about 2 minutes (make sure you protect the back of the screen from light bouncing off the ground. A piece of heavy black fabric or again aluminum foil will work). If you can get that design to wash out properly and the edges are all good and such, then it's a problem with your exposure time. 

How old is your lamp, by the way?

If the exposed emulsion still washes out then you've definitely got a problem with it and I'd say contact your supplier. 
I don't know if it will work, but I'd think you ought to be able to add another batch of diazo to the bucket and get it to work if that's the case.


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## Inkabilly (Sep 12, 2010)

Thanks for the tips! 

We will try the sun-exposure test tomorrow. 

The emulsion is fresh from our supplier and we mixed it and coated the screens on the same day, but there is no date / batch number on it, so who knows how old it is! I think we'll give the supplier a ring tomorrow too.

The lamp was purchased 3 months ago.


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## Vizual Voice (Feb 1, 2008)

As far as I can tell, the shelf life of the emulsion isn't related to when purchased but rather when sensitized.

re lamp: perhaps it might be aging and require a longer burn time. The sun test should tell you.
Good luck!


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## Inkabilly (Sep 12, 2010)

Thanks Scott!


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## Inkabilly (Sep 12, 2010)

Hello,

Okay we did the sun test and the emulsion still remained tacky so spoke to the suppiler of our Ulano emulsion and they agreed that sending out the sensitizer powder in an non light tight container was a bad idea so they agreed to send us a replacement.

They sent us a litre of emulsion and the sensitizer came in a light tight but smaller (39ml) container which we then filled with water and added to the emulsion. The sensitizer for the first litre of emulsion came in a 50ml container so more water was added and this worked fine.

I guess my question is how much water (distilled) and sensitizer should be added to a litre of emulsion and does it make much difference? My supplier dosn't seem to think it does.

Are emulsion is still tacky after exposure.


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## Vizual Voice (Feb 1, 2008)

Inkabilly said:


> I guess my question is how much water (distilled) and sensitizer should be added to a litre of emulsion and does it make much difference? My supplier dosn't seem to think it does.
> 
> Are emulsion is still tacky after exposure.


Should be enough water to mostly fill the container give or take. Doesn't make a huge difference. I usually fill it up to the shoulder of the bottle just to be consistent. You're just dissolving the diazo powder so it'll mix into the emulsion evenly.

Should not be tacky at all before or after exposure. That sounds like a moisture/humidity problem. Are you sure you're letting it dry completely before you expose it?


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## Inkabilly (Sep 12, 2010)

Hello Scott,

The screens are kept in very dry conditions and we always leave them a good 24 hours to dry before using.
I think the problem is due to an incorrect amount of sensitizer, we just had another delivery of emulsion from the same supplier and there was visually more powder in the container. Also there was a notable difference in colour when mixed with the emulsion.

We won't know for sure until we expose a screen tomorrow but fingers crossed eh!

Thanks for your help, we let you know the out come.


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## bluprussia (Apr 21, 2010)

Hi 
I got exactly the same problem... sticky on both sides of the screen...delivered in a white plastic bottle...and my supplier is Wicked Printing stuff...same supplier??? can we trust them???


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## Inkabilly (Sep 12, 2010)

Yes, our supplier is Wicked Printing Stuff, and we are in discussion with them about it. They sent us a replacement, which we were still not entirely happy with, as we had similar problems with it. We contacted them again and they said there are no problems with the emulsion, and asked us to email them details of our exposure procedure. We did this a few days ago and have heard nothing back.

They say they have had no other complaints, so maybe you should get in contact with them. Let us know what happens!


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## bluprussia (Apr 21, 2010)

I'll call them tomorrow...I'm really fade up with them, I had too many problem.
Probably they have had no other complaints because other people still trying to expose again again and again...I let u know !


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## bluprussia (Apr 21, 2010)

Hi guy ...I called the distributer direct and explain the situation, they insisted the problem was my exposure and they said they have had no problems with the emulsion as they use every day...final result was that I got a replacement batch of emulsion ( still with the Ulano label)...will see if it works now...have u still got the same problem?


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## Inkabilly (Sep 12, 2010)

we are now using a batch of emulsion sent out more recently, which seems ok. We are getting a good stencil, but the emulsion is still tacky when wet. We are having to to sit our screens back under our light once washed out to cure the emulsion hard. And so far the screens are surviving print runs of 100+ prints. 

WPS still haven't got back to us about our complaint on the second batch of faulty emulsion though ... we might just right it off and try a different supplier of Ulano!


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## Vizual Voice (Feb 1, 2008)

Inkabilly said:


> we are now using a batch of emulsion sent out more recently, which seems ok. We are getting a good stencil, but the emulsion is still tacky when wet. We are having to to sit our screens back under our light once washed out to cure the emulsion hard. And so far the screens are surviving print runs of 100+ prints.
> 
> WPS still haven't got back to us about our complaint on the second batch of faulty emulsion though ... we might just right it off and try a different supplier of Ulano!


So you're saying it's till tacky AFTER you wash out and it's still wet? That's normal. I misunderstood what you were saying earlier. I thought you meant that it wasn't ever drying on the screen once coated, but didn't realize you had sprayed it with water to wash out at that point.

You need to dry & "post expose" your screen. 

I usually just put them out in the sunshine for 5 or 10 minutes while I'm doing something else. Works great. If course you can use your exposure light, but it's probably not as quick.


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## Inkabilly (Sep 12, 2010)

Thanks for that Scott,......if we put the screens out in the sun shine in England for 10mins they would get even wetter.  Problem solved for now.


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## Vizual Voice (Feb 1, 2008)

Inkabilly said:


> Thanks for that Scott,......if we put the screens out in the sun shine in England for 10mins they would get even wetter.  Problem solved for now.


LOL! pesky wet sunshine....
We have that here in Florida too, but only for part of the year.


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## tommyp (Feb 9, 2011)

Hi, 

Sorry to drag this thread up from such a long time ago but I wanted to ask whether putting the screens out in the sun after exposing worked out? I'm having exactly the same problem, emulsion tacky to the touch on both sides after one or two prints. I've been really thoroughly drying the screens after washing and coating, the only thing I can think of is that the emulsions not great!

Any help much appreciated.


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## cocothecat (Apr 29, 2010)

Last batch of emulsion I had from WickedPrinting I leaves a white stain behind see below : (also in another thread I started so please delete if against forum rules)


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## Inkabilly (Sep 12, 2010)

Hia,

We did eventually solve our tacky screen problem ... it turned out to be a combination of things; I'll list them all, as any of them may also help you ... 

Firstly, the emulsion was questionable and so we have changed suppliers of our Elano Proclaim emulsion and are much happier with it!

BUT we were under-exposing ... 

We discovered that our stencils were not good enough. We were using a transluscent paper (velum?) rather than a clear acetate and the black was not dense enough, so the stencil was not coping with any exposure over 6 minutes.

So, we changed our stencil material and now use AGFA Copy Jet Film which we print on ourselves with an Epson Ink Jet printer and get really good dense blacks. This means we can now expose the screens for longer and get a really sharp image on the screen.

We do a post exposure too. After washing out the emulsion and drying the screen, we sit it under our exposure lamp for about 10 minutes.

We also now use a Stouffer 21 step scale on all our screens, which is a good guide to whether the exposure is correct. There is good info on what this is and how to use it on the Ulano website. 

We use 1000W halogen bulb at 22" above the screen, and our exposure time is between 10 and 11 minutes.

Hope this helps - it was a long process to solve the many variables, and it's tough to find answers as everyone seems to be using different set ups! so please feel free to ask any more questions, we'll be happy to help if we can! 

Good luck!


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## tommyp (Feb 9, 2011)

Thanks so much for all the info. My acetates are super dark and I'm using the same wattage lamp with just about the same exposure time so I don't think thats the problem. I think some new emulsion and post-hardening are in order!

Will keep the thread updated with my findings!


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