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screen printing => Waterbase and Discharge => Topic started by: SI on January 20, 2016, 06:34:30 PM
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Hello All,
Really having some issues with DC White. I have 4 different kinds (magna, Matsui, CCI, Union) and no matter which kind I use they are all so thick and don't seem to penetrate regardless of how much squeegee pressure I am using. using 70/90/70 Duro Squeegees with a LOT of pressure. You can see that with the blue DC ink (CCI) it is working just find, getting good penetration. But the white looks like cracked plastisol after one wash, and when i stretch test these I can see bare black fibers between the white, but as you can see in the pics the blue is fine. Ink isn't washing out really just not penetrating.
Is it possible to thin this down some to help penetrate? I really want to avoid doing the DC base with white over for this job. It is just 6 shirts. Going to reprint them tomorrow and at this point I am thinking of just using plastisol to save the hassle.
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Forgot to mention, 5% activator, both colors, Gildan 2000 shirts
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Add water. Your ink should not be thick. Discharge should only penetrate the fibers about 50% of the shirt. The wetter the ink the more it will fully coat the fibers. Don't stretch test discharge, that is not how it works.
Do 80 percent d-white 15 percent d-base and 5 percent water. I have done as low as 60 percent d-white on an order once just so the white would be super soft.
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You need an open mesh too in order to get the ink through it. We use 110 or 160 wi whites.
Water will help as SG said.
Pierre
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Thanks all, I printed that 180 S mesh pure white CCI-d. I'll give that a try tomorrow
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Well you know what you need to do- get the ink into the fabric -just a matter of how to do it now. Start with the ink.
CCI D-White is way thick out of the bucket, almost fluffy or "whipped". We amend it to get a proper rheology happening with it. I recommend as much water as activator, some penetrant, sofener and retarder to taste.
Magna on the other hand, we tested a bucket way back and it was pert' near ideal just the way it was. Just wasn't white enough for us.
Drop the mesh down to the lowest/most open that will hold the stencil over the run. Use a super durable, high resolution emulsion to help you on this mission. With the right combination you can actually be putting ink right through the shirt so don't go overboard but I like a 150/48 for DC white.
As mentioned DC ink forms a sulphuric crust after proper cure. It won't really feel right until washed and any bridging that happened will simply crack, that's normal, poor adhesion is not however.
Hope that helps.
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not water..use a clear base as water base isnt really waterbase, its more of a polymer that wont evaporate like water does.
I use matsui daily and mix in brite base to the white as its to thick on its own
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So would a Magna Clear base mixed with CCI or Union White DC work, or do i need to stay with the same brand?
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We cut D-White with D-Base.
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I use matsui daily and mix in brite base to the white as its to thick on its own
what's your mix? we use 75% white to 25% brite base as was instructed by PJ at Matsui... seems to not only print the best, but seems to stay brighter white longer through wash cycles.
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We also use Matsui. We use the Super 75 White discharge and still cut that with about 25% clear discharge base. Still looks bright white and easy to print manually. You can also add some Printgen retarder at 3-5% and it will help the ink flow easier, but that will also extend the dry time a bit so make sure it's fully cured.
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I use matsui daily and mix in brite base to the white as its to thick on its own
what's your mix? we use 75% white to 25% brite base as was instructed by PJ at Matsui... seems to not only print the best, but seems to stay brighter white longer through wash cycles.
200-250 grams brite base to 450-500 grams of DC white with 35g of activator. when its hot out, 5% printgen.
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Its cracks bcs of temprature. Increase temprature or increase times.
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Your not hitting that white PFP are you?
It just looks thick and more ON the shirt than IN the shirt?
Sent from my XT1585 using Tapatalk
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no, two strokes lots of pressure (anatol press so i don't have a PSI reading). It appears that I should be cutting it some with clear base which i hope to try today.
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We fixed our D white problems by giving it away.....lol Seriously though we run discharge through 200's and 230's all day long with no problems at all. Rutland white and Magna. You do not need to use a low mesh for discharge. You have something mechanically wrong from the looks of it. How much bend in your squeegee are you getting. Is the screen clearing?
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I second what zoo said. 135S or 150S for white "spot" art. equal parts water and activator to predissolve a bit, then add to the white. As much clear base as necessary to get it flowing how you need to penetrate. Usually around 20% max. I sometimes don't add any, usually when the ink is super fresh/just opened, and it is a moderate temperature, high humidity day.