# Emulsion bubbles not bursting



## StinkEye Dave

Guys, I have looked this up and tried all the tips etc but I am still getting Loads of bubbles (frothy) at the top of my DZWR emulsion. 
Does the temperature make a big difference? My 1st pot, there was no problem initially and my very first screen coated/exposed brilliantly! But when I went back to the same pot to coat another I stirred it and the froth never goes away even when left for days. I bought a new pot thinking it could be a funny batch but same prob again!
I'm thinking I may have done the first one in warmer weather. Should I try taking the pot indoors? Please help, it's driving me potty!


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## splathead

Are you storing your emulsion outdoors? Try it at room temperature.


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## EP USA

I put my emulsion in the fridge and it kept for along time. Also just try coating the screens with the bubbles and see how it burns.

Maybe double coat both sides to be safe, but you should be fine with the bubbles.


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## StinkEye Dave

It's in my garage which is my print shop now, lowest temp has been about 7°C (44°F). I've taken it indoors into a kitchen cupboard.
The last screen I coated with last bubbly batch had quite a lot of pinholes, nowhere near as smooth as my first. Think it was 2 + 1 coat.
If the bubbles don't disappear indoors maybe I could take most out with a spoon?!
Do you guys stir sensitised emulsion when it's been sitting for while again?


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## splathead

Stella Dave said:


> Do you guys stir sensitised emulsion when it's been sitting for while again?


Yes, we stir before every use, then let sit for the air bubbles to release.


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## StinkEye Dave

Okay thanks, that makes it even more of a nightmare! I'd have to wait every time.
I took the layer of bubbles off today and glad I did as it was almost like it had seen a bit of light and formed a scum on top. It went on okay but was streaky?! Thinking I may look into another product!


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## StinkEye Dave

Now this would be awesome to have! Vacuum chamber 
http://youtu.be/l7WRGfnJQaM


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## Ripcord

A few bubbles shouldn't hurt anything. Coat your screens on both sides (squeegee side last) and you shouldn't see bubbles on the coated screen.


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## StinkEye Dave

Just coated a screen for my first customer and it's absolutely covered in bubbles, I know now that it will dry covered in pinholes. I'm thinking the emulsion must just be bad quality.
If I leave the stirred pot for a day, it's covered in bubbles on top. The only time I got a smooth screen and no bubbles was after leaving it for 3 days which isn't much cope!


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## sben763

What emulsion. If your getting bubbles when coating your likely going too fast, not enough pressure or something else. I buy presensitized emulsion stir it once. Never stir again till its gone the bubbles are always on top. When I coat if I use a steady slow to medium coat the bubbles pop and disappear into the screen. If I go fast they are visible on the screen. If your coating a 2/1 the second coat should eliminate any surface bubbles. It best not to have any in the first place but the thicker emulsions seem to retain them. I've seen videos where they say to pop the bubbles in the container but never seen the need. 

If your concerned about pinholes you can always face coat the shirt side with a tight coat. And re dry them with the shirt side facing up.


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## StinkEye Dave

Diazo dual cure Water Resistant. I don't go to fast now, I used to but slowed down as it gave me streaks. (As I say the last screen before this one was great but emulsion was left settling for 3 days which leads me to think emulsion is the problem). 
I put quite a good pressure on it, wouldn't want to do it any harder. 2/1 coat.

Screen looks fine on first glance but when you hold it up to (safe) light it is covered in tiny bubbles. The holes are a real pain as I have to block them before printing.


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## gatorGRAFIX

I say it's time to switch emulsions. I use ProChem WR-14 from CCI. It is water resistant emulsion also. I keep it in the bathroom 24/7 because I know that room is climate controlled. You don't want it getting too hot or too cold.

Coat your screens and lay them flat to dry. I have built me a drying cabinet with slots in it. Also put a dehumidifier in there with it. Didn't cost me very much at all. Works perfectly.


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## sben763

Very possible the emulsion. I know what's avalibale to you on that side of the pond is slimmer picking then over here. I am using Saati Chem PHU. Premixed and water resistant.


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## gatorGRAFIX

You are probably right. I haven't even heard of that brand. LOL

I came up on CCI products that are now carried by Tubelight out of Memphis and their stuff seems to be far superior from what I was using over the last few years. Sales support from Mike at CCI is awesome too.


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## StinkEye Dave

It's only water resistant as I started out with water based ink but now use plastisol, that's another story though!
Thanks for input guys, it's definitely a bit of nightmare sourcing quality stuff over here which has always baffled me! 
Screen now dry again, covered in tiny pinholes! I'll try another emulsion.

Cabinet def not an issue. Btw I built a similar one to yours above!


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## gatorGRAFIX

Yeah, I use it for plastisol and discharge inks as well. When I use water based inks I coat the screens with a hardener liquid that CCI sells also. Good luck.

BTW - pinholes suck! I use to deal with them too until I switched plastisol brands.


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## micleross

*Here......... 

Go to www.floridaflex.com ...... buy a quart of SAATI Textil DW just to try it out. It's a dual cure diazo. $20 plus some shipping.

I had the same problem for a while...... could not figure it out and was very frustrating. *


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## StinkEye Dave

read back, I'm in UK


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