# Light box surrounding sublimation of dark polyester shirts



## ken7744 (Jul 8, 2009)

*Light box surrounding sublimation of non-white polyester shirts*

I am using a heat press to sublimate polyester t-shirts and when pressing dark colored t-shirts, I obtain a light box in the shape/size of the heat press platen on the shirt. Since this happens without using the dye sublimation paper (ie if I press a shirt with nothing but a teflon sheet), I'm assuming that it is a heat press-related problem. I'm also using a Vapor Apparel foam kit to elimate sublimation lines and dressing the shirts when pressing. I've experimented with three variables, temperate, time and pressure. I've ruined a bunch of shirts already. I seem to be able to decrease the light colored box by decreasing temperature, but then I fall below the manufacturer's recommended sublimation temperature and I start to have fading of the images I'm sublimating. I've tried messing with pressure, but doesn't seem to have an effect, same for time. Does anyone have the secret formula of pressure, time, temperature for sublimating t-shirts? I've tried different shirts from BAW, Badger, Vapor and still get discoloration of the shirt on all three. Could some of you share your settings in these three areas? What would be the probable variable that I should continue to adjust to address this problem? Any help would be appreciated. In particular, it would be great to know of settings for Badger, BAW or Cobblestone polyester shirts since I am a reseller of these brands. Thanks!


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## elhines33 (Jan 28, 2011)

Could there be something on the platen? Maybe some cleaner residue or something like that that could be having a bleaching effect. Are you using plain paper underneath and on top of the t-shirt in the press?


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## ken7744 (Jul 8, 2009)

Hi, no it's a brand new press and the platen is in prestine condition. I wiped it clean with just water to make sure there weren't any other chemicals from shipping. I'm using paper underneath the shirt and a teflon sheet on top between the shirt and heat source.


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## lben (Jun 3, 2008)

This happens every now and then. The heat changes the color of the fabric. Sometimes when the material cools down it will go back to it's original color, sometimes it won't. How are you sublimating on dark fabrics anyhow? Light pastels are as dark as you should go.


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## tshirtsrus (Jun 6, 2007)

You could use a Teflon pillow, with this there won't be pressure applied on the shirt against the platen edges.


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## agensop (Dec 11, 2008)

try the vapor foam kit to raise the print or a teflon pillow which does th same thing i believe. 



ken7744 said:


> Hi, no it's a brand new press and the platen is in prestine condition. I wiped it clean with just water to make sure there weren't any other chemicals from shipping. I'm using paper underneath the shirt and a teflon sheet on top between the shirt and heat source.


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## tshirtsrus (Jun 6, 2007)

agensop said:


> try the vapor foam kit to raise the print or a teflon pillow which does th same thing i believe.


Hi,
he did mention on his first post that he is using the foam kit, I suggested the Teflon pillow because is thicker, the one I use is at least 1/2 inch thick, I think the use of both is actually better, the Teflon pillow would alleviate the problem he is having with discoloration at the platen edges, and the foam kit would help with the transfer edges.


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## LB (Jul 25, 2009)

Here is what we have been doing and we have not had any weird lines or anything of the like.
Vapor apparel, 385F-plain paper on the bottom platen, teflon pillow inside the garment-plain paper on top of the transfer. We hand tear the edges of the transfer paper. Prepress for 10 seconds, then 385f for 50 seconds. Heat press is a Hotronix Swinger, Printer is a Ricoh 3300 with SG Sublijet gel inks.


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## agensop (Dec 11, 2008)

whoops missed that!



tshirtsrus said:


> Hi,
> he did mention on his first post that he is using the foam kit, I suggested the Teflon pillow because is thicker, the one I use is at least 1/2 inch thick, I think the use of both is actually better, the Teflon pillow would alleviate the problem he is having with discoloration at the platen edges, and the foam kit would help with the transfer edges.


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## ken7744 (Jul 8, 2009)

You can sublimate black on just about any color shirt except for the darkest of shirts. However, when I said I was doing darker colored shirts I was literally talking about non-white shirts. If I do anything outside of white shirts (ie the brands I mentioned) I have this problem. I tried the same exercise on a vapor t-shirt provided with the vapor foam kit and had the same result.


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## ken7744 (Jul 8, 2009)

LB said:


> Here is what we have been doing and we have not had any weird lines or anything of the like.
> Vapor apparel, 385F-plain paper on the bottom platen, teflon pillow inside the garment-plain paper on top of the transfer. We hand tear the edges of the transfer paper. Prepress for 10 seconds, then 385f for 50 seconds. Heat press is a Hotronix Swinger, Printer is a Ricoh 3300 with SG Sublijet gel inks.


 
Thanks for the details on your setup. I'm very close to this. Same temperature, pressure as defined in the vapor foam kit (ie depress foam by 50% when applied), time 50 seconds, plain paper on bottom, foam dressed between shirt layers, dytrans spray to hold transfer, teflon sheet on top.... get a box outlining platen... transfer does not have any lines (ie vapor foam kit is working). Taking the sublimation out of the equation. If I simply dress a shirt with the vapor foam kit and pop under the heat press I have the same result, so It definetly is heat press related and doesn't seem to be sublimation related.... Ideas?


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## emblar (May 2, 2011)

if the new printed t-shirt will get wet it become faded. that what i know if you use a hot press in printing a t-shirt.


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## rawbhaze (Jan 29, 2011)

The light box is from the vapor impregnating the already dyed fiber and diluting its color. Say the shirt is red. Sublimation happens at 350*. When you prepress without a transfer you are essentially adding a clear "color" (the vapor) to the red. You are then left with a lighter red when the pores of the fiber close. The same color concept as adding a cup of water to a cup of red Kool-Aid.

Do the following for a more visual example: 
*Cut two polyester swatches. (2"x2" is plenty) Print out a blue square and a couple of yellow squares. They should be a tad smaller than the polyester swatches.

*Place both swatches on the platen with a yellow square transfer on top of each. Press 'em.

*Let them cool to at least warm to the touch. Place the blue transfer on one of the pressed yellow squares in a side-stepped fashion. Do the same with a yellow square transfer on top of the other pressed yellow square. Press 'em.

-The first swatch will now be blue on one side, yellow on the other and green where the two overlapped on the second press.
-The second swatch will now be yellow on both sides and a darker yellow where the two overlapped.


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