Author Topic: URGENT...Printing on Polypropylene Bags  (Read 7435 times)

Offline ebscreen

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Re: URGENT...Printing on Polypropylene Bags
« Reply #15 on: April 05, 2013, 12:49:04 PM »
I think the majority of these bags are printed in China as flat fabric before being sewn. Probably with melamine based
inks or any other industrial waste they can sell back to us. Eco friendly grocery totes made of petro based plastics
printed with god knows what used once and thrown away.




Offline Parker 1

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Re: URGENT...Printing on Polypropylene Bags
« Reply #16 on: April 05, 2013, 04:39:11 PM »
I wish I could be everyone here a cold adult beverage. 

Finished the job 1,200pcs total. 
Had to reduce tunel temp to 300 and the suface temp. stayed btw 270 and 290. 

Again a HUGE THANK YOU to everyone for the help!




Offline Inkworks

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Re: URGENT...Printing on Polypropylene Bags
« Reply #17 on: April 05, 2013, 09:40:13 PM »
I think most ASI suppliers print these bags with air dry inks......Maybe the Nazdar folks can chime in on this subject...

If I recall correctly polypropylene/polyethylene products are print receptive for as short time after being molded/extruded/spun etc. In this short period of time they can be printed with many solvent and UV inks successfully. After a while they cure completely and most inks no longer stick to them. If that isn't the case with non-woven poly bags, then they most likely use corona-discharge priming to make the fabric print receptive just prior to printing. This type of priming, along with propane-flame priming also only last for a few days before the product reverts to something that almost no ink will adhere to properly.

Glad it went well for you Parker, once you dial it in they print pretty nicely!
Wishin' I was Fishin'

Offline mk162

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Re: URGENT...Printing on Polypropylene Bags
« Reply #18 on: April 22, 2013, 02:51:14 PM »
In case anyone is wondering, Screen And Digital supply carries a low cure additive...
http://www.screenanddigitalsupply.com/store/3804-low-temp-cure-additive.html

They are in NJ, so about 2 days shipping to me.

Thanks for the tip tony.

Offline Sbrem

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Re: URGENT...Printing on Polypropylene Bags
« Reply #19 on: April 22, 2013, 07:02:08 PM »
We do them, very rarely, without any real heat. We have a primer we spray on them, send them down the dryer, then use air-dry multi-purpose inks. A few extra steps, but absolutely no curling up. We send them through the dryer quickly at 250 or so, gas only, IR panels off. This gives us the best results, and we charge what we need to. If they want cheap, cheap, cheap, then we'll send it to an ASI distributor.

Steve
I made a mistake once; I thought I was wrong about something; I wasn't

Offline mk162

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Re: URGENT...Printing on Polypropylene Bags
« Reply #20 on: April 23, 2013, 08:58:27 AM »
I am more worried about other things like these stupid 50/50 neons from American Apparel, these suckers are bleeders.  If I can cut the heat, I would be VERY happy.