# Emulson Washing Out Repeatedly In Various Scenarios



## BSDesigns (Mar 16, 2010)

Completely Aggravated. Onto 4th round of treating screens with emulsion in varying ways and no matter what I do the emulsion is washing out around the image itself. Read hundreds of posts, tried various suggestions and nothing is working. Using Speedball Diazo, added the special agent to it and everything. Just bought new thinking the one i had was too old but new stuff is producing the exact same results. Using a 500w UV light placed 19 inches above screen. clear glass holding down image. Image printed with ink jet on overhead transfer paper that i have tried doubling up images to ensure light completley blocked out for image portion and still passing through for areas with no image. Tried everything from 3 minutes to 8 minutes and exactly the same reaction happening to emulsion on screen during rinse out. Using garden hose on low pressure. Spray screen down with water lightly right after i turn off exposure lamp. let sit for 1 minute and then run light running hose over image. usually takes about 2 minutes for image to start rinsing out and then will see portions of emulsion rinse out as well that aren't part of image. ensured that i have degreased screen and scrubbed it before letting it dry for 24 hours before reapplying emulsion, then letting emulsion dry for 15-24 hours before reattempting to burn image. When using hose, I've tried holding finger lightly over stream to increase pressure AND not where water just runs out lightly from hose and still getting emulsion washout away from image. Tried moving hose around on screen as well as holding in one spot until image started washing out, still same results. Replaced diazo with new and same results. I have no idea what's going wrong and haven't experienced this in over 2 years with several attempts and shirt orders going succesfully for me. now facing big order with new client and looming deadline and this issue has reared its ugly head and i can't seem to fix it and running out of time now. Please feel free to share as i've read almost every post i could find on this subject and tried numerous things but can't seem to figure out if i am 1) underexposing, 2) overexposing, 3) too much hose pressure (doubtful, truly no pressure has resulted in wash out as well), 4) not enough pressure and soaking emulsion too long waiting for image to rinse out, 5) new emulsion not really new and sat on shelf at store too long and thus replacement is giving same result , 6) or what???????


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## ole Jobe (Jun 16, 2009)

Definitely sounds like underexposure. Any light loses intensity over time. I use a 500 watt quartz shop light. Cost about $15.00. New my exposure tests 6 min. for 156 mesh. After a few months it goes up to eight, then ten. Without an exposure guide it is impossible to tell except by increasing time until you get good screen. God Bless.


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## gerry (Oct 4, 2006)

wow, thats a long sentence ... didnt quite get to the end
the glass your using is actually clear right? clear glass can also have uv filters in them ... not good, OR your diazo maybe beyond its shelf life.


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## Teamwear (Mar 12, 2007)

I also ran into a situation after 2 years of doint he same thing over and over.

It has to be something simple. 

Does your 500 watt light have a glass over it? if so, remove it. 

My first guess is that your screen is not exposed fully-go longer. Try as long as 15 minutes if there is no glass over the 500 watt light.

Last effort-are your screen contaminated? is there anything on them that does not belong? (stains, etc?)

Hope this helps-but I know that is is frustrating when something does not work as it usually does.


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## scottyjr (Sep 12, 2009)

You can eliminate the emulsion and light source as a possible cause of your problem by using something completely opaque, such as a piece of black electrical tape, on your positive next time you expose a screen. How about the areas away from your image? Are those areas staying intact?

With a decent emulsion and a properly exposed screen, the washout process can stand up to a really hard spray and hold all crisp detail including halftones.

You stated that your positive is overhead transfer paper. Is it paper or is it clear film?

This is an under exposure problem. Once you get the parameters of the process correct, you will be able to blast away at a screen with confidence.

- Scotty


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## PositiveDave (Dec 1, 2008)

Pop a coin on the next screen to ensure that there is a portion with no light then buy a stouffer strip or do this: http://www.t-shirtforums.com/t-shirt-articles/t106506.html


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## BSDesigns (Mar 16, 2010)

I just wanted to thank all of you for your input. I went back and a) removed the glass from my lamp and b) increase my exposure time to 15 minutes. While i definitely had to increase the water pressure to rinse out image, the image was the only thing that rinsed out and all of my lines were nice and crisp. It was actually the easiest rinse i had experienced up until this point so thanks again for your help.


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## Swagger11 (Jun 24, 2008)

Hey Bill,

I am by far not an expert but ....was gonna say we ran into similar issues when we started as well and you may want to look into a pressure washer to blow out the screens instead of a garden hose as you will find the longer you take to rinse it out at low pressure the more likely hood that the emulsion will get soaked and start bubbling out. Once we switched from garden hose to Pressure washer we havent looked back....Looks like you figured it out though and thats all that matters.


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## RichardGreaves (Nov 7, 2006)

The purpose of exposure is to change the stencil from something that will dissolve with water, to something that won't dissolve or breakdown with water. If the stencil dissolves - it's under exposed. If the image area doesn't dissolve - something cross-linked it either in storage or during exposure. 

The proof is in your results.

Old style emulsion using diazo sensitizer is excellent for water-based ink, but there are modern plastisol pre-sensitized SBQ emulsions that expose in half the time - especially with your low UV output quartz halogen work light.

You've been frustrated because you haven't been measuring your exposure with a US$10 Stouffer T2115 21 Step Transmission Gray Scale.
http://www.ulano.com/FAQ/FAQexposure.htm#Q1


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## JBYoungdahl (Apr 16, 2009)

RichardGreaves said:


> You've been frustrated because you haven't been measuring your exposure with a US$10 Stouffer T2115 21 Step Transmission Gray Scale.
> http://www.ulano.com/FAQ/FAQexposure.htm#Q1


Best buy I have made. Took 2 screens to get it right. Thanks for the advice Richard. Even though I read it for weeks befor giving up messing up screens and bought a stouffers.
Jeff 
WWW.embroideryIslandDesigns.com


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## RichardGreaves (Nov 7, 2006)

Where did you actually buy your Stouffer scale from?


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## red514 (Jul 21, 2009)

RichardGreaves said:


> You've been frustrated because you haven't been measuring your exposure with a US$10 Stouffer T2115 21 Step Transmission Gray Scale.
> http://www.ulano.com/FAQ/FAQexposure.htm#Q1


is there a digital file of this step test i could use to print my own test strips on my film? (i'm using an image setter and would prefer the test strips on my film rather then the inkjet film test strips we've been getting)

I have printed my own halftone step tests, i'm thinking i could create my own but if there's a free one available that would save me allot of time


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## RichardGreaves (Nov 7, 2006)

*Isn't there a free test for exposure?*

Yes, print your own opaque halftone test patterns - put one on every screen you expose.

Halftones fool your eyes into seeing shades of gray by mixing the color of the shirt with your ink. 

*Make a Control Guide*
Make a standardized pattern of known halftone dots in CorelDRAW or Illustrator. This should take less than 5 minutes.

5-10-20-30-40-50-60-70-80-90-95-100% in your favorite line counts.

Print several of these, or even save the image as a symbol and print it on every image you make a positive for.

Make a screen. When you develop the stencil you have a clue about which dots are washing out well. Remember, the stencil is swollen during development and needs to dry.

Print & cure the control guide.

Lay your positive on the print and use a magnifying glass to compare your print, to the positive.

Decide what you need to do to change the printed image and *make the changes in the art*.

Those 2% 5% 10% dots will be casualties of the equipment you have.

Now someone will tell you under expose the stencil so it's not completely cured. OK. You may get dots, but you may also get a stencil that doesn't survive.

*Stencil Hardness*
The Stouffer T2115 has been used as a standard photographic darkroom test positive since the 1930's. You need a halftone control guide and a test for stencil cure.

It's different - It's a real photographic positive with 21 steps of different density (steps), that simulates 21 different exposures - with one exposure. Because it's made under controlled conditions you can use math to calculate an exposure *correction, *and properly used, they will last a lifetime - and stop a lifetime of guessing.

*Exposure Math for Stouffer Transmission Gray Scale*
http://www.ulano.com/FAQ/FAQexposure.htm#math

Hardness (resistance to dissolving) is the most important step to stencil durability AND reclaim-ability.

You don't know me, but do you think I would promote something that even just costs US$10 if I knew how to get one for free? This isn't the place to save money.

If you want to test exposure for free, you can make a standard stepped manual exposure test. Unfortunately, this test can't be used on each screen to monitor the moving target of exposure.

*Homework*
http://www.t-shirtforums.com/t-shirt-articles/t106506.html article by PositiveDave

"Classic Exposure Step Test Video 4Mb 4 minutes


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## red514 (Jul 21, 2009)

*Re: Isn't there a free test for exposure?*



RichardGreaves said:


> Yes, print your own opaque halftone test patterns - put one on every screen you expose.
> 
> Halftones fool your eyes into seeing shades of gray by mixing the color of the shirt with your ink.
> 
> ...



well said and thanks for clarifying. for some reason i was thinking the stouffer strips were not reusable. I thought since i'm using film positives i could possibly out put my own stouffer strips and use them on every screen. 

This is were i got confused, you aren't suggesting using the stouffer strip on every exposure.. it's the halftone step test you suggest burning on every screen.
I will have the print shop purchase a stouffer strip


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## RichardGreaves (Nov 7, 2006)

*Re: Isn't there a free test for exposure?*

For visual feedback, like a speedometer, I want you to put a Stouffer T2115 on every screen you expose for the rest of your life to monitor stencil cure/hardness. Properly used it should last forever.









I apologize if I ever gave people the idea that it would cost you US$10 every time you tested a screen for exposure like temperature tapes. The developed result is "branded" into your screen until you reclaim the stencil. 

As a boss, I can check your screen for proper exposure months after it was made. 








You will squirm if a screen fails and I come out to the press and don't find a scar of a Stouffer scale that *PROVES* that you exposed the stencil to a specific hardness we've decided on.

"What do you mean you didn't put one on the screen when you made it?


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## red514 (Jul 21, 2009)

ok, now it's very clear 


i just spoke with the print shop and they gave me something similar to a stouffer strip that they received from there emulsion supplier. It's 2 separate films, one with 6 rectangles of varying opacity that is overlayed with the other film that has 6 corresponding rectangles that contain a halftone step test/line thicknesses/font sizes in each. 
I'm having them do tests with this but i've also requested they get the Stouffer strip you recommended. The Stouffer strip would work with any emulsion, correct?
They are using an emulsion from Murakami, i can find out the exact type if needed.


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## RichardGreaves (Nov 7, 2006)

Naturally, the exposure simulator/calculator wasn't in the screen room.

I'm sure it has a label that tells you who designed it. One film is a test positive, the other neutral density filters to simulate exposure.

Alas, exposure calculators expect you to bracket your exposure simulation by doubling exposure so you can see what results you will get from 6 simulated exposures.

No test positive knows what stencil you're using. Exposure simulator/calculators have a history of using the color change of diazo to judge exposure. SBQ stencils don't change color which is why it's so important to have a way to check hardness.

A Stouffer T2115 + some controlled test patterns like fine line & halftones should go on the edge of every screen you expose.

Murakami is a fine emulsion company.


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## red514 (Jul 21, 2009)

once again, thanks very much Richard!
i'm still going to have them get a couple Stouffer strips (they often burn 4 screens at once... i think this maybe another source of issues they're having)

i will keep posting about my adventures with screens and emulsion!


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## BroJames (Jul 8, 2008)

Greaves, how does the dot frequency calculator works? It looks similar to my lpi-based calculator. However, I use mine to see what lpi a particular mesh and/or emulsion is capable of reproducing. 








I also have one with various shades of black








I originally use this to see if my film positives are transparent enough and what opacity is capable of holding off UVs within my exposure time.


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## RichardGreaves (Nov 7, 2006)

What you have is a halftone test pattern that will show what dots will survive an exposure. 

Top to bottom you have different line counts. Across, you have different percentages of dots covering the open area. 40 lines per inch means there are 40 lines of dots in every inch.

A 20% dot pattern covers 20% of an area and fools you eye into seeing a tint of the actual color you might print. 

When you print this pattern, your art department will know what you can, and can't print - with that mesh, stencil and exposure.


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## BroJames (Jul 8, 2008)

Yes, that's the general idea.


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