Emulsion Question

[Larry Tywater]

Most customers using inkjet film and a pure photopolymer emulsion will have some issues with the film sticking to the emulsion during exposure. That is because the inkjet film has an aqueous receptive coating on it so that it can absorb the inks themselves to create a dark (dense) positive or negative. Pure photopolymer emulsions will absorb moisture from the air. When you put the two together they are both trying to absorb each others moisture, thus causing them to stick together.
We at Chromaline developed the Chroma Tech TD emulsion with this in mind. It does a great job of keeping the film from sticking. We coated a screen with 110 mesh on it with the TD emulsion and placed a piece of imaged AccuJet film on it. We then placed the screen inside a 100% humidity chamber overnight. The next morning we took the screen from the chamber and immediately drew vacuum and exposed it. Upon completion of the exposure we removed the film and it did not stick to the exposed TD emulsion at all. I knew that there had to be a better and cleaner way of keeping film from sticking than using powder. The answer was to create an emulsion that would not stick to the film.

[screenprintguy]

Murikami T-9 melts right off just like chromablue. Best of both worlds. I haven't tried the cryo stuff, but can say we are loving the T-9 for sure!! Nice to have one fast exposing emulsion that can be used for both plastisol and discharge and hold amazing detail.

[Colin]

How is the T-9 coating for you?  Any issues?

[Frog]

Most customers using inkjet film and a pure photopolymer emulsion will have some issues with the film sticking to the emulsion during exposure. That is because the inkjet film has an aqueous receptive coating on it so that it can absorb the inks themselves to create a dark (dense) positive or negative. Pure photopolymer emulsions will absorb moisture from the air. When you put the two together they are both trying to absorb each others moisture, thus causing them to stick together.
We at Chromaline developed the Chroma Tech TD emulsion with this in mind. It does a great job of keeping the film from sticking. We coated a screen with 110 mesh on it with the TD emulsion and placed a piece of imaged AccuJet film on it. We then placed the screen inside a 100% humidity chamber overnight. The next morning we took the screen from the chamber and immediately drew vacuum and exposed it. Upon completion of the exposure we removed the film and it did not stick to the exposed TD emulsion at all. I knew that there had to be a better and cleaner way of keeping film from sticking than using powder. The answer was to create an emulsion that would not stick to the film.

I am betting that way more folks use ink jets than photographic image setters, so building this characteristic into a wider selection of photopolymer emulsions seems like the thing to do.

[screenprintguy]

How is the T-9 coating for you?  Any issues?

I use a Monster Coater, doesn't really have a sharp or dull edge, I would guess somewhere in the middle. My dark room stays pretty warm with the dehumidifier running all the time, so I think storing the container that is in use in there helps a little with the thickness. I was told you can add a small amount of distilled water if you want, but I'd rather not. I really haven't had any issues coating though, it flows really smooth. EOM seems to be awesome, I don't have a gauge, but by touch it's getting what I used to get with Chromablue easily. When coating S-Mesh, I only go 1/1 and flip the screen to coat the opposite side reverse direction. Any T mesh one directional 2 and 1. Not sticky at all when read for production. Chromablue sometimes would be kinda sticky, so like say an underbase screen, when boards got warm would stick to the shirt until a little lint got on the emulsion, always happened with chroma blue no matter what we did. This stuff seems nice and hardened, even though we aren't using a hardener.