Emulsion tackiness after exposure

[islandtees]

We use Chromablue. When you expose it is very tacky after exposure. The film sticks and many times the black ink comes off and gets ruined. We have done like others with the baby powder. We are in Florida.
The screen room is a seperate room with A/C, dehumidifier, and heat. The screens are checked with a moisture meter. They are dry.
Curious if anyone expierenced this and what did you switch to?

[mooseman]

we have different emulsion, different film (waterproof) and the same problem even in the cold dry winter here in central, coooooold & drrrrrry  in NY.
The source is the waterproof coating on the film, the fix is in your powder bottle.
mooseman

[screenxpress]

The source is the waterproof coating on the film, the fix is in your powder bottle.
mooseman

Mike,
I had recently switched to CTR and found the same thing happening down here in Houston.  Well I guess that gives it away that it's not very dry.

Can you explain the "fix is in your powder bottle"?

[Frog]

Can you explain the "fix is in your powder bottle"?

Baby powder, Talcum Powder, a light dusting of the screen is the band aid for this problem.

[alan802]

We have the same problem with Chromablue and Saati PHW Red, AC'd dark room with dehumidifier, 35% humidity or lower.  Baby powder is the only remedy besides changing emulsion.  The PC-701 I sampled a few weeks ago did not have much post exposure tack, it certainly didn't take the ink off the film positive.  I'm trying to remember if Kiwo One Coat did this and I think it did.  Pretty much all the higher solids content emulsions/pure photopolymer we've used have been notorious for this problem, except the PC-701.  Dual cures don't have this problem at our shop.

This recent talk about emulsion has made me rethink our current emulsion usage and I'm going back to testing out new emulsions.  I think we all should do this with ALL of the products we use every year or two.  There is always something better around the corner or a product that you've never used that outperforms your current one, but if you're not open minded to trying new products then you'll be left in the dark and wasting time and money.  There was a shop in my area that seriously didn't know more than two different ink manufacturers existed.  Wilflex and Union were their only choices, and there is no telling what else they didn't know about emulsion and screen chemistry.  I know most shops don't use these forums for information and rely on an outside sales rep or maybe the wind to keep them up to date on new products and techniques, and then I guess there are some that could give a damn about that because they finally found something that worked somewhat ok and just stuck with it.

[ericheartsu]

Where do you baby powder yoru screens? We used to do it, and it made a mess in our dark room.

[Admiral]

Another way to fix it is with a CTS unit.


I have only found this to be an issue if the humidity gets too crazy in the dark room.  A light powdering fixes it like others have mentioned.

[IntegrityShirts]

We have the same problem with Chromablue and Saati PHW Red, AC'd dark room with dehumidifier, 35% humidity or lower.  Baby powder is the only remedy besides changing emulsion.  The PC-701 I sampled a few weeks ago did not have much post exposure tack, it certainly didn't take the ink off the film positive.  I'm trying to remember if Kiwo One Coat did this and I think it did.  Pretty much all the higher solids content emulsions/pure photopolymer we've used have been notorious for this problem, except the PC-701.  Dual cures don't have this problem at our shop.

This recent talk about emulsion has made me rethink our current emulsion usage and I'm going back to testing out new emulsions.  I think we all should do this with ALL of the products we use every year or two.  There is always something better around the corner or a product that you've never used that outperforms your current one, but if you're not open minded to trying new products then you'll be left in the dark and wasting time and money.  There was a shop in my area that seriously didn't know more than two different ink manufacturers existed.  Wilflex and Union were their only choices, and there is no telling what else they didn't know about emulsion and screen chemistry.  I know most shops don't use these forums for information and rely on an outside sales rep or maybe the wind to keep them up to date on new products and techniques, and then I guess there are some that could give a damn about that because they finally found something that worked somewhat ok and just stuck with it.

Aquasol is still my choice for a non tacky emulsion that you can coat until the cows come home.

The Chromablue exposes just as fast as Aquasol, with the tackiness and smelly side effect was my only complaint.  Everything else was on par.  But I too feel like it's the consistency of really hard taffy when pulled from a dehumidified dark room.  Just doesn't feel as dry as it should I guess, but it definitely is dry.

I'm going back to Aquasol for now and will also order a gallon of the Kiwo discharge emulsion from Tubelite.  Also, with as many screens as I'm burning these days, it would benefit me to find one that comes in a 5 gallon as well. I just can't fathom how to dispense it into my coater, how in the world do people do that, with a pump?

For the discharge printing, I put the murakami hardener on dry screens and it holds up perfectly for longer water-based runs.  Yeah it's one more step, but it's actually easy and only adds a couple minutes.  For the piece of mind of not switching emulsions, it's well worth it and predictable.

[mooseman]

Where do you baby powder yoru screens? We used to do it, and it made a mess in our dark room.

we have a cabinet where we keep our exposure ready screens. When we select the screen we simply take it from the cabinet hit it with the powder spread it with our hand and place it directly onto the exposure glass.
We do this in open light , yes fully open light with no filters or other precautions.

mooseman

[spotcolorsupply]

I just can't fathom how to dispense it into my coater, how in the world do people do that, with a pump?

Ulano has a pump for 5 gal buckets... Or most people I know just pour into a gallon

[Gilligan]

What if you put a spigot on the bottom of the bucket?

[screenxpress]

Where do you baby powder yoru screens? We used to do it, and it made a mess in our dark room.

we have a cabinet where we keep our exposure ready screens. When we select the screen we simply take it from the cabinet hit it with the powder spread it with our hand and place it directly onto the exposure glass.
We do this in open light , yes fully open light with no filters or other precautions.

mooseman

Pssst.  Next time put the film on it for better results.

[jasonl]

I never understood why some shops put their exposure unit in a dark room.  I like to see what I am doing.  I put mine out in the light with ZERO protection and it works PERFECT!

[screenxpress]

Ditto

[Prosperi-Tees]

I don't even have a darkroom but if I did the exposure unit would not be in it.