Dyfrig

Hi,

We have been printing with permaset water-based inks for over a year and have not had any problems until this week. For some reason our screens have started sticking to the t-shirts when printing. It's not the actual ink in the open parts of the stencil that's sticking but the emulsion around the print area?

The Emulsion we use is Azocol Z1, solvent and water resistant. I'm trying to think of something that e have changed recently but can't figure anything out. We have been exposing our screens for longer than we used to - as before the emulsion was coming out a bit slimy on the back.

I would imagine that the only problem that could arise from over exposing is that the stencil wouldn't wash out - but it's washing out easier than it did with the shorter exposure.

After the first exposure we always dry the screens thoroughly and expose again to harden the emulsion.

The only thing that I can think of is that we haven't dried the emulsion properly. We have recently started to use our drying cabinet to dry out wet screens after degreasing - could there be more moisture in our drying cabinet that's stopping the emulsion dry properly? It feels dry to the touch when it comes out.

Am trying a new set of screens now and drying the emulsion for longer.

Any help much appreciated.

Thanks

Dyf

 

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splathead

How old is the emulsion? Could that be an issue?

Otherwise, since it appears the drying cabinet is the only change that has occurred, try drying the screens without using the cabinet and see if that solves it.

Does your cabinet have circulation?

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Joe
knowledge is Power

 

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Dyfrig

Hello,

The cabinet doesn't have circulation - it's home made (not very good!).

Have also tried a new pot of emulsion but no luck - still trying diferent things and trying to find something that we have been doing diferent?????

Thanks

Dyf

 

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Rusty44

How long are you letting the screens dry? I live in FL - humid to say the least, and always use a fan for circulation to dry them. I have enough room in my dark room area that I can stack the screens flat using blocks of wood between each layer to offset them enough for the air to circulate around them. The fan isn't aimed directly on them. I usually just let them set overnight and they are totally dry in the AM ... I print with waterbased inks as well and the emulsion I use is Saati - Grafic HU

Sandra

 

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Dyfrig

Hello,

Still not having any luck over here. Doesn't matter how long I expose the screen the same thing keeps happening-the stencil still washes out fine - and I have re-exposed the back of the screen once the screen is dry but as soon as I put some water on the printing side of the exposed screen I can scratch the emulsion off?

I dont think the emulsion is drying properly. Even if I let the emulsion dry over night, and dry it with fan heaters it still seems to be slightly tacky.

Have ordered a diferent brand of emulsion - so hopefully this will work.

 

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Rusty44

If I were to guess, I would say there is definitely something wrong with that batch of emulsion. You should contact the mfg about it.
Sandra

 

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