# how long can emulsion sit on screen once the image is burned?



## dzingeek (Jan 4, 2010)

i'm new to screen printing (never done it yet) and i was wondering after you put the emulsion on your screen and let it dry and then burn your image to the screen how long can it sit after you wash out the image (i want to reclaim the screen)?

and what about after you use the screen then wash out the ink (water based) how long can it sit before you want to reclaim the screen?


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## Unik Ink (Nov 21, 2006)

It's best to do it within a few days. If not, it makes is much harder to reclaim.


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## Stitches (Oct 2, 2006)

I always reclaim right away. If it is late at night I will do it the next morning. You are inviting problems by letting them sit.


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## printing40years (Dec 27, 2008)

They can sit forever


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## in2infinity (Dec 8, 2009)

They can sit essentially forever. I'd had screens that went 5 years before I reclaimed them. No difference between older and newer screens in the reclaiming process. If you plan to store them for more then a couple days just make sure you take some extra care to get them really cleaned up well.

I usually keep three classes of screens ...

1.) use, reclaim and reuse - for those jobs you know are one offs.
2.) Use hold for 3 months to a year, if the customer doesn't come back or you need it for something else in an emergency then reclaim and reuse
3.) Keep the image until it dies... for those customers that re-run frequently. By "dies" that may mean the emulsion is warn out, in which case we reclaim and re-expose with the same image. It can also mean the screen itself is worn out ... in which case its strip and restretch.


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## RichardGreaves (Nov 7, 2006)

If you have completely cure/cross link all the sensitizer in the stencil 

and

If you don't chemically bond the stencil to the mesh with strong solvents the stencil can't handle

there is no limit on how long before you can wait before reclaiming.

Pressure washer always helps.
Don't let the stencil remover dry on the stencil or it can also lock the stencil in the mesh.


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## 73eyes (Jan 22, 2010)

How about ink? Do you guys clean your screens out before storing them if you're hanging on to the stencil? It seems like this leads to a lot of grease buildup on my screens, but I haven't pinpointed the problem completely, yet.


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## in2infinity (Dec 8, 2009)

I've heard plastisols can be left on a screen a couple days without a problem. I always clean mine when I'm done so I've never actually tried it. UV ink I have left overnight ... no problems there.


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## BillyV (May 8, 2009)

I have actually left ink on a screen for over a month once because the customer keep saying he wanted another run on different type of shirt... 
sure enough almost six weeks later he calls and when I went to print I just used a little Sprayaway to open the screen and off I went, using the same ink that was left on the screen from the original order...

When I went to reclaim the screen there was bit of ghosting that came out after dehazing.


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## thumbsuprod (Oct 21, 2011)

ok me and my friend are complete morons.. We can figure out everything else aka built a perfect rotating 4 person station.. BUT WE CANNOT FIGURE HOW TO BURN THE IMAGES INTO OUR SCREENS.. We took a plastic bin screwed lights on the bottom of it 500w a piece have them facing straight up a piece of glast ontop where the lid would go then the screen some foam and a black top on the top.. IT NEVER WORKS.. We are dead broke and cant affor a light box right now and need help badly.. If anyone has any suggestions that would mean alot!!!!!!


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## PhilR (May 3, 2011)

thumbsuprod said:


> ok me and my friend are complete morons.. We can figure out everything else aka built a perfect rotating 4 person station.. BUT WE CANNOT FIGURE HOW TO BURN THE IMAGES INTO OUR SCREENS.. We took a plastic bin screwed lights on the bottom of it 500w a piece have them facing straight up a piece of glast ontop where the lid would go then the screen some foam and a black top on the top.. IT NEVER WORKS.. We are dead broke and cant affor a light box right now and need help badly.. If anyone has any suggestions that would mean alot!!!!!!


This is my exposure setup. Just a shelf with 2 500w halogen floods installed about 16" above. Murikami & CPS Diazo emulsions both expose within 10 minutes. The critical part is your films. They have to be black as black. My printer puts out films that are at least as opaque as my welding mask.


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## sben763 (May 17, 2009)

thumbsuprod said:


> ok me and my friend are complete morons.. We can figure out everything else aka built a perfect rotating 4 person station.. BUT WE CANNOT FIGURE HOW TO BURN THE IMAGES INTO OUR SCREENS.. We took a plastic bin screwed lights on the bottom of it 500w a piece have them facing straight up a piece of glast ontop where the lid would go then the screen some foam and a black top on the top.. IT NEVER WORKS.. We are dead broke and cant affor a light box right now and need help badly.. If anyone has any suggestions that would mean alot!!!!!!


Did you remove the glass from light. Most glass on halogen light have uv filters. Is your image completely washing out.


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## thumbsuprod (Oct 21, 2011)

Does it really need to be an inkjet printer cause we've used laser printers


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## PhilR (May 3, 2011)

thumbsuprod said:


> Does it really need to be an inkjet printer cause we've used laser printers


You can use laser printers but more than likely you'll need to double up your films as the toner doesn't always lay down dark enough and you generally can't control it to any real degree.


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## ScreenFoo (Aug 9, 2011)

Some of the better old lasers you can control the bias voltage on the laser to get darker positives, but you still pretty much have to use a spray to darken it. As I understand it, an excellent laser positive will have about 1/2 the UV blocking ability of an excellent inkjet positive.

In other words, they still stink out loud compared to an inkjet setup, except for the cost of consumables.

I guess if most of what you do is athletic one offs, *maybe* a laser would be better. If you're stuck with it, see if you can pick up a can of Toner Aid, or Casey's Ultra Black. Use good ventilation.

I've heard of people using a clearcoat on laser positives to darken them--all it did for me was guarantee the positive would be fully laminated to the screen and would self destruct on removal. It'd be cheap to try though.


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## cataHMN1 (Nov 2, 2011)

in2infinity said:


> I've heard plastisols can be left on a screen a couple days without a problem. I always clean mine when I'm done so I've never actually tried it. UV ink I have left overnight ... no problems there.


You can leave plastiosol for a couple of days on the screen but I don;t recommend using that ink again. I've seen problems with that plastisol washing of....so you better clean everithing


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## RichardGreaves (Nov 7, 2006)

*Plastisol is low maintenance*



cataHMN1 said:


> You can leave plastiosol for a couple of days on the screen but I don;t recommend using that ink again. I've seen problems with that plastisol washing of....so you better clean everithing


Plastisol ink is not effected by air like food - only heat. There is no difference to plastisol if you put it in a bucket, or leave it in the screen - for years.

Household dust _*will *_settle on open ink, but doesn't effect the final cure. Stir it in and it disappears. Take a hand full of swept up dust and throw it in a white ink screen and it disappears.

This is perhaps the single reason trouble free, 100% solids plastisol is so popular - low maintenance, and it cures faster than water-base because there's no waiting for evaporation.


If plastisol washes off, you didn't bring the shirt & ink film completely to 300F+ degrees (follow your ink specification).


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## BillyV (May 8, 2009)

*Re: Plastisol is low maintenance*

I have left ink on for two weeks and no problems.


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