# non-woven bags



## deltsigjoe (Sep 11, 2008)

Hello all. I am trying to print on some non-woven polypropylene drawstring sports Bags. Are there any special precautions I need to worry about? Any special temperature? Any special belt speed? Any special ink or additives?i

Any tips and/or tricks are greatly appreciated. 

Thanks so much.


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## Twisted Grafix (Oct 5, 2016)

Use a low cure white and add low cure additive to additional colors. DO NOT add more low cure additive to an already low cure ink, as it will not do what you want. We usually add about 5% by weight. The curing temp gets reduced from 320 to about 275 with plastisol. You'll burn through (literally) a ton of them your first time, but once you figure it out, they are a piece of cake.


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## deltsigjoe (Sep 11, 2008)

My first try resulted in burned bags 


I had read another trick to add a nylon catalyst to the ink, run it at a low temp, and air dry. Have you heard anything similar?








Twisted Grafix said:


> Use a low cure white and add low cure additive to additional colors. DO NOT add more low cure additive to an already low cure ink, as it will not do what you want. We usually add about 5% by weight. The curing temp gets reduced from 320 to about 275 with plastisol. You'll burn through (literally) a ton of them your first time, but once you figure it out, they are a piece of cake.


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## FlashDave (Jan 9, 2017)

I printed these non woven bags on an M&R Sportsman auto a few years ago.

I needed to get creative with the process as the bags can easily and quickly burn under normal ink flashing/curing temperatures so I made a flat board with a hole larger than the print area but smaller than the shirt board, this was covered with tin foil and positioned under the flash unit. This allowed the heat (flash) to be applied only to the print area and not to the substrate hanging off the edge of the shirt board which is prone to burning/melting. This method allowed me to use sufficient heat when flashing between colours without risk of burning the bag. It is important to have good tack on the shirt boards as any lifting of the bag can result in burning.

Also, I put a clear ink under the entire image down first, this gave a nicer surface to lay the colours on to. The yellow and blue were under-based with white to make them pop. Nylobond was added to all inks therefore allowing for very low heat curing through the tunnel dryer. They turned out great!


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## Twisted Grafix (Oct 5, 2016)

I've never added nylon catalyst to inks, so I really don't know if that would work. 

If you added the low cure additive and still burned the bag, the dryer temp is too high, the belt speed is too slow, the ink is too thick, or a combo of any . 

You could try to print a thinner layer of ink by increasing the mesh. A thicker deposit will take longer to cure, allowing the heat to build up and melt the bag before the ink cures properly. So, if you print with a 110 mesh, it will take longer to cure than if you print with a 230 mesh at the same temperature. That may be part of the issue as well. We print with the thinnest deposit possible to produce the most opacity. This keeps the ink cure temp and dwell time at a minimum to keep the bag from melting, but fully curing the print.


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## Merry (Jul 19, 2018)

we've has success with conventional Nazdar all purpose ink- no heat, just rack them to dry. pretty simple, but we just stick to one color on those puppies


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## gardenhillemb (Oct 29, 2015)

We print these bags using catalyst and run them through the dryer just hot enough to dry the ink and then let them sit a day before boxing them up. We use regular plastisol for colored inks and nylon white. Never had a problem with them.


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## deltsigjoe (Sep 11, 2008)

What is the catalyst you use?


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## gardenhillemb (Oct 29, 2015)

We use International Coatings Catalyst 900. We mix it 1:16 by volume or just a little more. Works great.


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## deltsigjoe (Sep 11, 2008)

Hello and thanks for the info.
By chance, do you know what the temperature is when you dry them? 









gardenhillemb said:


> We print these bags using catalyst and run them through the dryer just hot enough to dry the ink and then let them sit a day before boxing them up. We use regular plastisol for colored inks and nylon white. Never had a problem with them.


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## Ripcord (Sep 2, 2006)

I think I'd flash them for a few seconds and then cure them with a heat press. That way you can get the temperature just hot enough to cure and no hotter and it's a very even heat. With a dryer (especially a small dryer like mine) there's a lot of variance in temperature as you send things through it one after another it cools off and you need to keep adjusting it. A heat press would apply direct heat right on the print so it would cure very quickly. Don't clamp it down, just let the heater rest gently on the print for a few seconds. Use parchment or kraft paper between the print and the element.


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