Cold Foil Problems

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manishbjain
Posts: 1
Joined: Thu May 03, 2018 7:48 am

Cold Foil Problems

Post by manishbjain »

Hello,

We have recently started flexo printing and have tried a couple of jobs cold foiling but are facing a few problems . Can anyone suggest possible solution ?

1st Job
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Material : Chromo
Anilox : 300 ( Metal Anilox , not ceramic )
Foil : Gold from ITW
Problem : Transfer almost fine but font and design edges not sharp , looking crooked and unfinished.
Job 1.jpg
Job 1.jpg (142.3 KiB) Viewed 607 times

1st Job
---------
Material : Chromo
Anilox : 300 ( Metal Anilox , not ceramic )
Foil : Gold from ITW
Problem : Transfer not happening properly , uneven and incomplete transfer
Job 2.jpg
Job 2.jpg (121.56 KiB) Viewed 607 times
csn7203
Posts: 16
Joined: Fri Aug 23, 2019 10:34 am

Re: Cold Foil Problems

Post by csn7203 »

I have no expierence with metal anilox rolls. What BCM roll are you using? a 300 line to me says it has a deeper volume, we typically run our cold foil adhesive on a 500 lpi 3.4-3.6 bcm. Along with that if we start to get real spotty like your picture is showing we swap out rolls right away. Also if you are over impressed that could be creating more spread in the adhesive causing unsmooth edges. Also check that your nip pressure is on or even, or if you are using film material that you are running a corona treater. Hope any of this helps.
Richprints
Posts: 12
Joined: Tue May 09, 2023 11:10 am

Re: Cold Foil Problems

Post by Richprints »

you can also check the angle and tension on the rewind side of the foil roll. Try different rollers to pull from if necessary.
Printerman513
Posts: 9
Joined: Sun Jan 05, 2020 10:35 am

Re: Cold Foil Problems

Post by Printerman513 »

I would look more into the length of web that your cold foil is laid onto your substrate. What's the rating of the durometer your nip applying the foil with? for this I'd suggest orange/blue nip (75-90) with some corn starch applied to the nip with a tight rip on the foil. ITW in the past I've experienced the tension on your unwind/rewind is extremely critical for most rolls (ive had some terrible ones) but the most important factor most everyone overlooks is the plate tape/plate durometer being on the harder side, try some blue/green tesa tape or purple/white 3m plate tape with a 250 lpi anilox with one less or one more idlers for dwell time, Best to have multiple batches of foil or having a spare roll of silver to test more variables.
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