# How long can a screen stay emulsioned without exposing?



## nd6 (Jan 4, 2009)

Hi there, please can somebody tell me how long a screen can stay with emulsion on it pre exposure without hardening as i have had a delay with the image and can only do it tomorrow??

Thanks in advance


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## kmapparel (Jul 15, 2008)

I believe if you use pre-sensitized emulsion (already mixed when you got it) you are good for at least a week and I think up to two weeks maximum. Just need to make sure you don't pre-expose it with any light before you are ready to use it.

-Nate


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## mrvixx (Jan 13, 2009)

I have exposed screens more than a month and are still ok


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## brianmot (Dec 24, 2008)

what if your emulsion is not pre-sensitized.. What is its bottle shelf life?


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## out da box (May 1, 2007)

The bottles will last months BEFORE you add water and sensitize. I have had coated sensitized screens in my darkroom since December, just exposed 4 today, no problems other than a bunch of small pinholes I think from dust.


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## kmapparel (Jul 15, 2008)

Once you add the water/sensitizer mix the shelf life decreases to a few months at best. I've heard that storing your mixed sensitizer/emulsion in the refrigerator helps but i've just gone with the presensitized emulsion as it has a shelf life of a year or so.


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## mrvixx (Jan 13, 2009)

nd6 is asking about a coated screen no the container of emulsion


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## RichardGreaves (Nov 7, 2006)

Coated screens are very stable, but diazo sensitizer will breakdown in 4-6 weeks because it absorbed water when you added it to the emulsion. 

The worst thing that can happen with old screens is if they fail, you have to reclaim - like tasting milk that you didn't drink fast enough.


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## TshirtStan (May 4, 2008)

As a general rule according the Fresener's.....3 months once a screen is emulsioned until you use it. Some will say up to 6 months. I clean/coat 36 at a time so I have enough for a few weeks. I have used them up to 2 months without any problems. Yes...keep them dust free or at least blow them off with air before you expose them.


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## alan802 (Mar 24, 2008)

We have exposed screens that have been sitting for 6 months without any problems. We use a pure photopolymer emulsion and a good darkroom.


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## cmyk (Dec 3, 2007)

it really depends on the emulsion you have.
some types of pre-sensitized emulsion cand last on a screen for up to 6 months, if the screen is wraped in a black plastic bag and kept at 68 F. degrees.
if not wraped, it will only last for 4 weeks.
when kept in the bottle, the emulsion is good for 1 year.

[media]http://www.fotec.ch/english/techinfo_pdf/Foteco_1860_E.pdf[/media]


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