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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Silkscreen on Powdercoat Adhesion Problem
Q. I've been searching the Web for answers to a Silkscreen on Powdercoat problem we are having. There are still questions I have no answers to about the Powdercoat specifications.
We do not do the process ourselves, but have it done for us. We have a flat door which is Powdercoated (specified as black with light texture) then Silk-screened (white). The silkscreen is not large (about 1.5"H x 3"L), and the line width is from 0.04" to 0.10" thick. The problem is the lettering not passing the Tape Test (using 3M type 600 tape). Also the lettering will come off a few days later even if it passed an earlier Tape Test.
I have been told that Powdercoat exudes a silicone or plastisizer and this may be the problem. At this time we are in full production with serious problems.
Is this something you can help shed some light on?
Kevin Durkee- Laconia New Hampshire
2001
2001
A. I think you're on the right track, powders contain waxes, silicones and other slip agents to make them less likely to scuff or show wear. Your best bet is probably to find an ink to use in your screens that will adhere in spite of these materials. A second option may be to look at a different powder formulation, but that may cause other problems.
Try to find a solvent based ink, one that has a chance to really adhere to the surface.
Jeff Watson
- Pearland, Texas
A. We have also experienced this problem in the past. I have found that using a baked white epoxy ink works very well. In fact I haven't found any thing the ink I use won't stick to, but you must bake after screening 300 °F for 25 mins.
We have also used a white catalyzed epoxy with good results. Although the air dry works better with a light solvent wipe in the area to be printed. Hope it helps!
Brian Bell- Holyoke, Massachusetts
2001
A. We use ink on many different types of powder, both with catalyst and air dry. For optimal adhesion I would recommend baking with catalyst between 175 and 225° for 1 hour. What we use is excellent for adhesion and anti-yellowing.
Mark Fowler- Urbana, Iowa
2002
2005 Q. No problem. Use Naz Dar Superset ink. One part system, works well, baking times are vary. Only thing is--it stinks. We really want to find the old Naz Dar BE series, and the best was Ink Dezyne's EB series, but they were bought by Naz Dar. We'd really like to find some black, if anyone reading this knows of any. James M. Stewartscreenprinting - St. Thomas, Ontario, Canada A. Enthone Series 50 epoxy inks have worked very well. No adhesion problems. Vince Bunker- Santa Rosa, California January 6, 2010 ---- |
A. We are Silk screeners for 45 years. The problem you are having is the powder coat.
It may contain 4% Lanco this is a wax flow agent and is not for silk screening! Too much to explain in this on how to get it to take. For sure you need a 2-pack ink and then in the oven.
- England
November 19, 2012
Q. The problem is more than likely the wax's or silicone in the epc and it always seem to be when it's a black satin finish; we are having problems yet again with adhesion.
2-pack inks seems okay for the start, then after a while just peels away. I have reverted to trying the old gloss enamel ink, trouble is the drying of the stuff.
So here I am on a Saturday morning and having to wait till Monday to see the result!
screen printing - leicester uk
June 1, 2019
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