# problem with emulsion washing out



## Locklear (Nov 24, 2006)

I have been using Spike brand emulsion which is purple in color.

My images are showing up with great detail, however, after a few washouts, from time to time the emulsion is getting knocked out around the image and I'm losing detail...sometimes to the point where I cannot use the screen to print.

I am using a screen wash which instructs me to spray off with water. I THOUGHT that the emulsion should withstand this, but obviously it does not always work that way.

I'm getting really sick of having to remake these screens. Any suggestions? Thanks in advance.


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## Fluid (Jun 20, 2005)

> after a few washouts, from time to time the emulsion is getting knocked out around the image and I'm losing detail..


Are you printing the same design/screen every other day type of deal and cleaning after each use?

If so you might want to use a press wipe rather than screen wash.


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## RichardGreaves (Nov 7, 2006)

*Re: Emulsion washing out*

If the stencil washes out it was not exposed enough.

Perhaps not enough time. Perhaps not enough power to penetrate to the back of the stencil _where it attaches to the mesh._ Purple is harder to penetrate than light green or light blue.

You are probably cooking this steak, medium-rare. And only from one side. Think about cooking a pancake or a hamburger and not flipping it over. Time will not solve that problem, you must have penetration.

Properly cured, no dual-cure stencil will be effected by even the strongest water blast or screen wash.

Properly cured I have used dual-cure stencils for more than 100,000 impressions.


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## Locklear (Nov 24, 2006)

Richard-

I should clarify...I am getting great printing results from these screens for a while.

It's just after multiple washouts (10-20) that the emulsion is coming off, and it only comes off around the edges of the images.

Does that change anything about what you said?


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## RichardGreaves (Nov 7, 2006)

*Re: Emulsion washing out*



Locklear said:


> Richard-
> 
> I should clarify...I am getting great printing results from these screens for a while.
> 
> ...


Nope. You are not doing anything abnormal. Call up the 800 number at Chromaline and ask Mick Orr if SPIKE should breakdown after textile printing and 20 washups with _______. SPIKE is a dual-cure and dual-cure's don't break down.

Water and some scrubbing are breaking down something in your stencil. Some part of the chemical makeup of the film is breaking down as you work with it.









The day I visited this place it was raining and they were drying their screens inside the darkend room on the right with both doors open. Hmmm.....

Moisture in the stencil will block the cross linking of the chemicals.
Not enough UV to make them crosslink.

These are the two most common reasons stencils break down.

Take a coated screen and attach a positive you want to use. Now take a piece of carboard and tape it over the image area with some margin.

Now take the screen out into the sun on a sunny day (it's almost spring!), for 5 minutes. 

Take the cardboard off when you get back inside and expose the rest of the stencil in the usual manner.

Print and wash, print and wash and see if the sun exposed screen holds up better. 









You don't show where you live. What is the Rh indoor and out today? How do you dry your screens? Dry is not heat. If the air around your screen is not in the 40% to 45% Rh range, there will be more moisture in the air than the stencil and the water will stay where it is. 

You need Mother Nature's help to kick that lazy water out of the stencil. She loves equlibrium and balance. If the air is dry, Mother Nature insists that the water leave the stencil. 

Mr. Dehumidifier may be your new best friend.


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## Fluid (Jun 20, 2005)

great post Richard. Classic visuals. I dont know what I would do without our dehumidifier. One of the many good investments a shop should have.


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## Locklear (Nov 24, 2006)

Thanks for the advice. I think I may not be drying properly.


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## fox (May 22, 2008)

I've been having the same problem, using wooden frames that get damp. dehumid sounds like the answer.


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