Best flatbed for corrugated plastic

[parrott]

We are tradittionaly a screen printing company, but have been in the digital market for about 10 years. With the flatbed market taking over screen printed short runs, we are looking for a flatbed that would fill this niche. We print a TON of corrugated and aluminum signs, but also print styrene, sintra, foamboard, etc. We are looking to shift most/all of our short runs (50 pieces or less) to a flatbed while keeping our screen presses busy with larger quantities.

We have received print samples from Oce, EFI and AGFA but we are not married to any of them. Oce said their inks will only last 60-90 days on corrugated when in the sun. Since this is the majority of our business, this pretty much puts them out of the picture. EFI's samples and adhesion looked good, but I think they are a out of our budget. The AGFA prints looked amazing and the adhesion seemed great. Just curious what the lifespan of the ink is.

If anybody has owned and operated any of these machines for 6 months could you please give me your input? Have you had any complaints about corrugaed ink adhesion? Any ink fading on corrugated? How critical is it to have TRUE squared sheets of corrugated?

Thanks in advance!

 

[klmiller611]

We have an AGFA Mv, in service since Dec 2008. We don't do a lot of coro that needs to live long. However, late last spring, don't remember exactly when, printed a 3x8 sheet with our logo and address to put on the back fence. Our logo is primarily red, with some black. The sheet was installed and without close inspection, looks as good today as the day I printed it. I did not laminate or do anything special for it.

Regarding adhesion on coro, it was a bit of a problem initially. Usually my issues were when printing a full bleed and immediately cutting it caused flaking. If it set for a day before cutting, it usually was much better.

On the last batch of material, I switched to the brand of coro that AGFA recommended, and keep fresh stock in hand, run the lamps on high, cool the coro with a fan on a stand and the adhesion issues seem to be gone.

To align on the AGFA, it uses a bar lowered to align against. Obviously, if you have a crooked end, it will not be straight on the board. I trimmed some coro with a drywall t-square to get the ends straight when I need that.

 

[SignManiac]

We print with an HP FB950. 4mil and 10mil coro is our primary material we print on and then PVC. We always wipe down with 91% Isopropyl alcohol first.

We had one odd ball run recently where the ink flaked off after a while. Tech support told us to turn our lamps down from high setting to medium setting. Apparently the high lamp setting was over cooking the ink.

 

[Gino]

We were told the opposite. Turn both our lamps on at once going both ways. The ink needs to be baked on more. We have a Dilli... 6 color.

 

[particleman]

Our m4f we're basically doing the same as listed here. Fan + both lamps on high + both shutters as suggested by agfa. The ink is on the corro really good at that point. The corrugated issue was a deal breaker for us too, the OCE we ruled out right off because of the info on adhesion we heard and read. EFI, well do some searches...

 

[omgsideburns]

I'm running an old MacDermid (HP) Colorspan 72uvr.. prints on coro great. Solachrome UV ink seems to stick to anything, relatively long life in the sun which is great here in florida.

Not sure what newer machines are comparable but I imagine things have gotten better.

 

[sjm]

I'm running an old MacDermid (HP) Colorspan 72uvr.. prints on coro great. Solachrome UV ink seems to stick to anything, relatively long life in the sun which is great here in florida.

Not sure what newer machines are comparable but I imagine things have gotten better.

They have but coroplast, I am not sure whether it's because it's guillotine cut but it is never quite as square as a sintra or styerene 4 x 8 sheet.

My screen printing friend has the same issue with coroplast.

 

[G-Artist]

Getting poly sheets from anyone that are truly square can be a chore.

Sometimes just getting a sheet that is the right size (not off by an 1/8" or more) can be frustrating as well.

Most folks will be happy to know that several suppliers are working on a top coating to
facilitate flat bed printing. It is a tough road because of all the ink differences between manufacturers
plus getting a one-size-fits-all coating which will accommodate both UV and solvent inks is a real challenge.

They make coro that resists static, coro that will allow an electrical charge to pass through it
and they make coro that is flame retardant so they will eventually make one that print
shops can count on their inks sticking - all at a price, of course.

 

[ejeffe]

Vendor Disclaimer! Jeff Edwards from Océ here.

The primary issue with Coroplast (or any polypropylene) is that low surface energy negatively impacts adhesion of any ink. The best way to ensure optimal adhesion on this particular material is to raise the surface energy prior to printing. This can be done by priming (cleaning) the sheet with a substance designed to promote adhesion on this particular media or by flame or corona treating the media. Most plastics companies sell a brand of fluted polypropylene that they will guarantee has been corona treated within 7 days before shipment. The reason adhesion is so important on this particular media is because it shrinks/swells wildly with temperature variation. If the ink/media bond is weak the ink surface will crack and eventually flake off in part or whole resulting in sign failure. If you use decent media, or treat it chemically, electricaly or with heat before printing, adhesion will be spectacular.

As for the assertion that Océ inks only last a short time on this media I can assure you that is not true. Océ inks are manufactured by Sericol, who happen to know something about ink as one of the world's largest manufacturers of screen printing inks. They use automotive grade colorants (pigment materials) and are expected to last 2+ years in outdoor applications. Assuming that they have been properly cured to the media of course.

 

[econolinesigns]

We have never had a problem on Coroplast done on our Solara Ion. The ink adheres to just about anything. We have had our Ion for just over one and one-half years and we are happy with it's abilities. We even print vinyl floor mats for a local artist who sells them nationwide. Outdoor like of any UV ink, at best, no matter what the manufacture claims is probably no more than six months to one year without lamination and two to three years with lamination.

 

[robracer]

Vendor Disclaimer! Jeff Edwards from Océ here.
As for the assertion that Océ inks only last a short time on this media I can assure you that is not true. Océ inks are manufactured by Sericol, who happen to know something about ink as one of the world's largest manufacturers of screen printing inks. .

I can agree with what Jeff has said here, we are screen printers & have been using an OCE 7070UV flatbed for printing corrugated PP for 3 years & have never has a job fail due to adhesion, the flute we are using is locally made & the corona treatment is regularly dyne tested by our staff & always passes the test so if there were ever going to be a problem it would more than likely be the ink, but luckily we have not had an issue. We always cut the printed flute the following day to allow for the ink to settle as well, we have found it will flake if cut when freshly printed.