Wet-on-Wet Screens Sticking

[Racer Tees]

Been having an issue when trying to run some prints wet-on-wet.  The first color printed on the underbase looks fantastic, but each color after begins to stick the screen to the shirt and the print becomes blurry.  It is a 5 color job, all screens are between 23-26n except for the 3rd screen which is at 15n.  I dont think that lower tension screen is causing the problem as it sticks worse through each color.

I can flash between each color and the prints come out very nice, but I don't want to be flashing between every color as I have a few 4-6 color jobs coming through and that would kill my efficiency.

I've been using Texsource inks as they are only about 10 minutes from me and I can get anything I need first thing in the morning on the way in.

Garment - 100%
Off-Contact - 3/16"
Underbase - Tex Cotton White (not reduced) - 80dur squeegee - 160 mesh
Other Colors - Tex GEN Series - 70dur squeegee - 305 mesh

Texsource has a Fine Wet on Wet Base as well as a Halftone Base.  Would using either one of these help my situation?

[aauusa]

I have never used those ink before so I will tell you what you can check for without the ink.

make sure the white base is cooled down before the next color goes on top

make sure your under base is fully gelled before printing the next color. 

I will notice that the ink when flash will go from wet to tacky to gelled.  make sure it is past the tacky part but not cured

those are some issue you may want to consider if you have not already

[screenxpress]

Only time I remember that happening is when I 'did' flash between.

[DannyGruninger]

Make sure the pallet temp is not too hot where it's curing the inks from the inside of the shirt out. That will cause inks to get tacky and start building on screens next in the order. Do you have a picture of the artwork you can post?

[Racer Tees]

I never thought about pallet temp.  But now that I think about it, they do somewhat stick if I flash between each color.  The prints still come out perfect if I run them this way, but it just never dawned on me.

Have checked the flash time multiple times on this one.  Getting them just past tacky, but not fully cured.

I run aluminum pallets without any rubber material on them, but I have 6 stations so it has time to cool.  I leave a station between me and the flash so that I don't get cooked. but that still leaves 3 stations before it gets back to me.  Would it help the heat soak in the pallet if I were to get the rubber material on them?

[blue moon]

try this:
lower your off contact a little, move the 15N screen to the front, speed up the stroke and flash longer (maybe even twice as long). Then grab 20 blanks/scrap shirts and run them through. By the time you get to the last one, it should start working. Let us know if you if it does not.
Also call TEX and confirm the inks are WOW compatible. Many inks out there just can't do it. You will want something that is designed specifically for WOW printing. They might also have an additive to make it work better, but in the end you should use the WOW inks as it makes a huge difference.

pierre

[Racer Tees]

Also call TEX and confirm the inks are WOW compatible. Many inks out there just can't do it. You will want something that is designed specifically for WOW printing. They might also have an additive to make it work better, but in the end you should use the WOW inks as it makes a huge difference.

This is the reason I chose their GEN series inks.  Reasonable price, and designed for WOW printing.

Going to try to do a little R&D before heading out of here for the day.

[Racer Tees]

I just popped off a few on white without the underbase.  They printed amazing.  The 15n screen does attempt to stick, so I stuck it at the beginning of the print order and I couldn't be happier with the print... on white that is... without the underbase.

As I said earlier, my platens are aluminum and covered in platen tape, but do not have any platen rubber.  I never paid much attention before, but they retain a LOT of heat.  I hit my underbase, flashed, and let it sit for a minute or so with a fan blowing on it and it was still hot to the touch.  Top colors still stick once printed on the underbase.  Underbase is flashed until dry to the touch, just past tacky.  It sticks so bad that the entire image area of the last screen doesn't come up until I lift it.

Hard to see in the picture, but you can tell that the ink is pulling up on the back side of the screen.

[prozyan]

Sounds like the Tex Cotton White isn't a good white for an underbase, at least unmodified. 

[Racer Tees]

Any suggestions for an underbase white ink?  I'd be willing to try a few different inks to find one that I like.

I'm printing this design on 100%, but I'm split between 100% and 50/50 in my typical jobs.

[blue moon]

What kind of press?

Pierre

[screenxpress]

Is the underbase a solid layer of white or is it halftoned? 

The underbase does not have to be solid layer.  Just solid enough to provide sufficient opacity.

[Racer Tees]

What kind of press?

6 color, 6 station, Brown Master Printer

Is the underbase a solid layer of white or is it halftoned?

Solid

[Gilligan]

If you are on a manual press, do yourself a favor and get some Meteor White by Galaxy Ink.  Spoiled is the word I use to describe my printer now.

[3Deep]

I hate to be the bad guy here but if your printing on a manual you got to rotate anyway...you might find flashing each color might be best and I don't think it will kill your speed that much if any.  Once you get moving your pallets want be that hot, you would be very surprise at how printers flash every color, they might not admit it but it happens.

darryl