under cured?

[cleveprint]

So we printed an order last week on some Gildan hoods. 3/Color. White (Wilflex Bright Tiger), red and yellow (both Wilflex Epic series). The top colors were printed over the top of the white as it was going on navy. Luckily the job is for the electrician who rents from us in our building and they came right over and arent too pissed, but the red is washing off. Not the yellow or white though. We have been pretty religious lately about checking dryer temps because we are printing a lot of diff type of shirts and want to make sure things are curing right. Our guy at the end of the dryer said they hit 325.

The fronts and backs of the sweats were printed on diff days as well. Backs were on the auto and fronts manual. Both front and back are doing it too. Is it possible that I have a bad batch of ink? Ive never heard of that, but its very weird that not all the colors would crack or wash off.

[Frog]

How do you measure your temp?

[jvanick]

Also, what kind of dryer do you have?

Reds are notoriously difficult to flash cure, so I'd guess if you have an IR dryer, the same might occur.

[DannyGruninger]

I've had this issue in the past and it was overflashing the underbase.... Maybe take a look at that

[kingscreen]

I'm with Danny.  My first thought is an OVERflashed underbase.

[Frog]

I may say the same thing, except that, over the years, I have been asked to cover up existing designs, and damned if the new plastisol didn't adhere and launder just fine, going over fully cured plastisol.

[gtmfg]

I'm going with overflashed. Been there done that.

[blue moon]

is the red coming off and the white staying or are they both washing out?

pierre

[cleveprint]

just the red coming off. not the white. white isnt cracking or fading at all. took the two test prints we had in the defect box home last night and washed them. both looked fine after washing and drying. BUT, they were both tshirts, not sweats. i have one of the unworn sweatshirts and im going to wash it myself tonight as well. just to double check.

i guess i could see over flashing it. the only issue i see with that is that i did the backs on the auto with a quartz flash and we did the fronts manual (had a lot of zipper hoods and reg hoods so we put it to the manual side) with an IR flash. just weird that we would both over cure it.

they have a bunch of pieces that they keep in stock in their closet. any chance of saving those if this final wash test comes off? maybe run them thru the dryer again or heat press em?

screen printing is fun!! 

[alan802]

I've heard about overgelling/overflashing a base and have never done it although we've tried it (not intentionally) and the signs sure point to that possibility.  The only thing that has me thinking otherwise is the fact that one was flashed with a quartz and the other an IR unless it's a shop-wide occurrence to flash for long periods.  What type of flash times do you do on both the auto and manual?

[cleveprint]

being that they were sweatshirts, the quartz flash was pretty quick. i hate to flash them too long at the risk of them shrinking. my guess would have been approx 3 sec. its a pretty large area of white that needed to be flashed. usually as long as i can give it a quick touch and its not too tacky, thats my science...

flash times similar for the manual as well. our guy said probably around 3-4 sec. sorta tough to gauge as its not on a timer.

[3Deep]

I'm leaning to over flashed base as well, but did you stir up your red ink before printing, I know this sounds stupid, but could make a difference in how ink reacts once all the plastizers has been mix...just a wild reach on that

darryl

[alan802]

being that they were sweatshirts, the quartz flash was pretty quick. i hate to flash them too long at the risk of them shrinking. my guess would have been approx 3 sec. its a pretty large area of white that needed to be flashed. usually as long as i can give it a quick touch and its not too tacky, thats my science...

flash times similar for the manual as well. our guy said probably around 3-4 sec. sorta tough to gauge as its not on a timer.

Well, I can tell you that probably 90% of the plastisol printing shops flash for much longer than 3-4 seconds so take that for what it's worth.  We start around 4 seconds and depending on the ink deposit and length of the job we can get down to under 2 seconds easily but we've never had an overgel issue with a base.  I think that it still may be an overgel problem but not because of your flash times.  There is something wrong with the ink.  Has any of the ink been modified with any additive?

[starchild]

The highlights of the Bright Tiger includes Good Flash Properties and Can be used as an Flashed Underbase White.. Which leads to the conclusion that the plasticizer used in the Bright Tiger has low surface tension and (when flashed), will maintain a low critical surface tension so that the top colors will adhere readily.

The Bright Tiger precautions does state that you should avoid over flashing as it can result in poor top color adhesion.. Hmm.. The critical surface tension has a very narrow range- Well that's a contradiction to it's highlights.

Now if the top color (Red) plasticizer, naturally has a higher surface tension than the Bright Tiger, then the two inks will be incompatible and you may need to use a wetting agent in the Red to lower it's surface tension so that it can adhere to the gelled Brighter Tiger.

[cleveprint]

being that they were sweatshirts, the quartz flash was pretty quick. i hate to flash them too long at the risk of them shrinking. my guess would have been approx 3 sec. its a pretty large area of white that needed to be flashed. usually as long as i can give it a quick touch and its not too tacky, thats my science...

flash times similar for the manual as well. our guy said probably around 3-4 sec. sorta tough to gauge as its not on a timer.

Well, I can tell you that probably 90% of the plastisol printing shops flash for much longer than 3-4 seconds so take that for what it's worth.  We start around 4 seconds and depending on the ink deposit and length of the job we can get down to under 2 seconds easily but we've never had an overgel issue with a base.  I think that it still may be an overgel problem but not because of your flash times.  There is something wrong with the ink.  Has any of the ink been modified with any additive?

agreed. i start at 4 sec for basic tshirts and go up or down from there. i just always think that fleece flashes way faster and to eliminate the risk, i start way lower on sweats. i guess these seemed to flash quick. inks havent been modified. straight out of the bucket.