# Which ink do you use to screenprint polypropylene bags?



## ginny2girls (Feb 25, 2007)

I have a customer that wants to print on polypropylene black bags-"eco" friendly bags. These bags can't be cured-just wondering how to print on them.


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## Solmu (Aug 15, 2005)

My supplier sells an ink that is used specifically to print on those bags (i.e. it's marketed _for those bags_, it's not just a different ink that is compatible). I'd contact your supplier and ask them if they provide such a product.


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## Fluid (Jun 20, 2005)

Most of those bags are strictly for advertising. they will never be washed as the material is "paper" thin and would fall apart in a wash. We have printed with normal palsticol inks with a lil bit of nylabond added. run through the dryer at a super fast belt spees to get a tiny amount of heat to essentiall gelll the top layers of ink so its dry to the touch. havent had any issue so far. As lewis mentioned getting a specific ink might be the best option without knowing the specifics of the job and the end use of the goods.


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## BKSARTS2 (Apr 17, 2008)

This is the exact printing issue I have on the plate at this moment for I googled it and find myself a new member at this forum. Where can you order this additive may ask?


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## midwaste (Apr 8, 2008)

The Nylabond (Union Ink, I believe) additive Fluid mentioned is widely available, as are multiple other nylon bonding additives


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## BKSARTS2 (Apr 17, 2008)

Thank you so much, but also What temp yah have the dryer set or any given range, wondering flash cure can also give a pre curing base so when it goes through the dryer it will be fully cured.


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## BKSARTS2 (Apr 17, 2008)

Thanks again. Lots


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## swannn32 (Sep 1, 2006)

The nylabond will get really hard after awhile. I accidentally left it on a squeegee for the weekend and had to scrape it off with a spatula on Monday. 

I run the bags through with the heat panels raised up as high as they will go at about 30 seconds. I think the temp was around 300 ? I'm not sure, can't remember the temp. You can send one through as a test at the lowest temp and just keep raising the temp till you see the bag getting tight, then back down the temp a bit and good to go.


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## Boomerbabe (Sep 5, 2009)

We just screened about 30 of these with plastisol ink and used the heat press set at 300 degrees, medium pressure, about 12 seconds (give or take a second or 2) protected with a teflon sheet. Even washed one to see how it all would hold up. Worked perfectly. 
PJ


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## printing40years (Dec 27, 2008)

That ink won't recycle


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## chuckh (Mar 22, 2008)

When printing dark ink on light colored polypropylene, we have used NazDar 9700 air dry ink.


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## tryplecrown (Jan 24, 2007)

Just to throw a little more info out there. I just ran a couple of hundred tan (natural) colored Polypropylene bags with a red imprint. I ended up just running some Union ultrasoft red on them. The image came out a bit shiny/glossy but it worked pretty good. I did what was mentioned here as far as speeding up the belt A LOT and turning down the temp on the dryer. Those things melt really easy. In fact as I was testing, it looked like the first sign of it being too hot was that it started to pucker around the imprint. But I was shooting them with my temp gun and it looked like they were hitting around 300 for just a second. Thought about adding some nylabond, but when I pulled out my bottle, it was rock solid so I had to toss it. But adhesion didn't seem to be a problem. 

One other thing to consider if you're quoting or setting up preliminary artwork on these. The bags we used had the handles sewn down the sides of the bags. There was about a 6" space between the straps or handles, so that needed to be considered. I think our final artwork was about 5.5" wide by about 10" tall and we ran them on a kids platen. I used a 6" squeegee, and sometimes it was sort of tricky where the handle was preventing the image from printing if it was too close. Also, this is sort of like printing on nylon where you want to try to hit it right on the first past at about medium speed. Since the fabric doesn't absorb any ink a second pass can make the image muddy. 

Just thought I'd throw that out there. Hope it's helpful to someone.


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## mrvixx (Jan 13, 2009)

I just did 100 of these. mixed 12% nylabond to plastisol ink. sped up the belt and worked excellent, they got to about 300 degrees.


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## partymom42 (Jan 31, 2011)

Can I ask what you charged your customer to print on these bags? Did you charge a set up fee? If you have a customer that has thousands of bags 500 per order, what you would charge them for printing? It is all one color print but multiple ads on one bag. 

Thank you in advance.


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## partymom42 (Jan 31, 2011)

Sorry..... I guess I should of put that the customer also supplies the bags for you.


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## ben3cero (Jan 30, 2012)

Im about to try printing with plastisol and adding nylabond.
and Ill let you know how works out!​


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## Fixico (Dec 3, 2011)

Try a little nylon bonding additive and a low cure additive. Holds up really well for me.


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## boneshaker (Sep 4, 2012)

What about water base inks? Are they able to hold in that material?


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## printing40years (Dec 27, 2008)

Your ink supplier is a good source of advice. Some ink manufacturers also have tech support 800 numbers. 

Nylobond will get hard in the container if not closed tightly and if it gets too warm or too much humidity. I recommend keeping it in the refrigerator. Before putting the cap back on the container, wipe the lip completely clean using solvent wash up and a rag. Make sure the cap is clean as well. Then the cap won't glue itself on permanently. That way you never throw away Nylobond. Add more than 12% when printing White. Mix well. You can all find low temp additives for plastisol to make them cure at lower temps than 300F which melts the poly bags. Don't print the image any thicker than necessary. The bags still will not wash well.


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## wncprinter (Sep 15, 2017)

This morning I tried WM Plastics LC. The ink will cure at 240F and leaves a nice satin like finish. I used a 200 mesh screen and I didn't use any nylabond, and it seems to pass all the rub tests for adhesion. i've discovered that "hard" flooding the stencil (like you were going to do a one pass white) ensures that you get the ink deposit you want in one pass.

I have run a few hundred using Texsource's "Universal" ink. This ink only cures at 300F, so if you are using an additive to reduce the curing time for whatever ink you have, this would likely be a similar product. I also didn't use a bonding agent with that run, either. The was a little rub off of the ink on some of the bags. I was using a 156 mesh for that run. I probably should have used a 200 mesh for that one.


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