Back side printing station issue IWASAKI

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vladav85
Posts: 4
Joined: Sat Oct 14, 2023 12:19 am

Back side printing station issue IWASAKI

Post by vladav85 »

Hello all,

We have an IF 330 Iwasaki flexo with UV curing in the printing house, we have installed printing station fot print from the back side in single-pass. Here we mostly only do stains like black mark. We also have a problem with the press in these jobs. In one place on one edge of each spot, we have a larger application of ink compared to the entire spot. That part that remains on the edge is very thin but has a larger coating of paint and later does not dry through the UV lamp and smears later in the roll when it is rolled up.
Ink is applied with anilox Apex Gtt "S". The same plate on other statio do great job. In attach is photo of our print.
Do somebody any idea how to solve this ?
Attachments
0-02-05-5aea6cabb1197eb973b5b8a7e00f1b19666e376722e3873cb2914453b4827e44_c79569dd.jpg
0-02-05-5aea6cabb1197eb973b5b8a7e00f1b19666e376722e3873cb2914453b4827e44_c79569dd.jpg (210.69 KiB) Viewed 899 times
BJH
Posts: 6
Joined: Wed Nov 08, 2017 7:10 pm

Re: Back side printing station issue IWASAKI

Post by BJH »

Do you have bearers on the plate? Leading edge looks to be keying a thick bearer at 100% should take care of it
vladav85
Posts: 4
Joined: Sat Oct 14, 2023 12:19 am

Re: Back side printing station issue IWASAKI

Post by vladav85 »

Yes, we have bearers on plate . All ours plates have bearers.
Attachments
IMG-53d10165e21804101a3c64ab47e6ebd0-V.jpg
IMG-53d10165e21804101a3c64ab47e6ebd0-V.jpg (82.93 KiB) Viewed 865 times
BJH
Posts: 6
Joined: Wed Nov 08, 2017 7:10 pm

Re: Back side printing station issue IWASAKI

Post by BJH »

Make those bearers solid and you should see some improvement. If you need job info/cross-hair just invert everything.. but should be solid the whole length of plate.
Frank Burgos
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Re: Back side printing station issue IWASAKI

Post by Frank Burgos »

It looks like the plate is not travelling at the same speed as the surface of the substrate. Your overall repeat is probably long or short, depending on which way the web is travelling in this image. If left-to-right, the image is short. If right-to-left, the image is long. Check your repat.

If that's the case, it's also possible that the plate and anilox surfaces are not travelling at the same speed, resulting in a buildup of ink on the leading edge of the images.
vladav85
Posts: 4
Joined: Sat Oct 14, 2023 12:19 am

Re: Back side printing station issue IWASAKI

Post by vladav85 »

Thank you all. I'll report back with the results.
vladav85
Posts: 4
Joined: Sat Oct 14, 2023 12:19 am

Re: Back side printing station issue IWASAKI

Post by vladav85 »

You were right. The print cilinder turned slowly. We changed the parameters on servo and got an improvement. Thanks Frank .
Frank Burgos
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Posts: 1256
Joined: Wed Dec 31, 1969 8:00 pm
Location: North Carolina
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Re: Back side printing station issue IWASAKI

Post by Frank Burgos »

You bet. Happy printing!
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