Coating Industry - Gravure Roll Cleaning

I don't really know what a gravure roll is, but is there any way you could coat, maybe just the pockets, with some kind of non stick teflon coating, or something similar?

My experience has been with the coating of moisture-cureable solvent-borne polyester/polyurethane adhesives and solvent-borne pressure-sensitive adhesives (PSAs).

PSAs are pretty forgiving as they are dissolveable even after they are dry.

Once moisture-cure solvent-borne adhesives and coatings are dry, they are resistant to the solvents that they were dissolved as well as most others.

I haven't seen a PTFE coated roll, but it sounds like a good preventive solution, at least for lower cell-count/higher coating thickness ones. The best way to keep them clean, is to know what you are working with and have a workable cleaning procedure in place before subjecting the roll to the working medium.

Hi, if you're interested about learning more about it, visit http://www.pyradia.com/webconverting/web-coaters/gravure-coater.html.

We had an automated cleaner that sprayed plastic pellets directly at the roll. The spray arm moved back and forth along the length of the cylinder and the holder would incrementally rotate it at intervals.

I cannot recall the manufacturer.

Here's something to let you see what I mean:

http://www.xlwash.com/media/Leaflet_Roll_Cleaners_XL_2.pdf

Here's a cleaning solution:

http://www.brisgo.com/products/cleaning-solution/

It's amazing what you can find when you do an internet search with the words "gravure" and "cleaner"

Thanks guys. I don't know if the teflon coating would work since one would want the resin to stick to the surface of the rolls when coating.

Because we would use this process as an alternative it would take a lot of convincing to purchase a roll cleaning machine. I have searched google, and I have found a cleaning solution from Dynaloy, but they are pretty expensive. I started this post to check if there is any tricks that I had not thought of, but I guess we have to pay the cost of doing business.

Thanks again.

Hi AKUR,

I don't know what your setup is, but ours used a "pan" (holding the adhesive or coating) that the gravure was partially submerged in - approximately 25% of the diameter of the roll. The roll was "wiped" as it rotated with a Doctor Blade before coming in contact with the substrate to be coated.

When finished with the coating run, the pan is drained of the adhesive or coating and the pan then filled with the cleaning solvent. The gravure rotational speed is then increased. The increased speed and the decreased viscosity of the solvent, with the Dr. blade firmly in contact with the cylinder, facilitates high turbulent flow and a very thin laminar layer in the cells (good, fast cleaning).

The pan is then drained and a solvent-soaked rag is held against the cylinder (by hand, wear gloves) and going back and forth across the roll as it rotates. This is done at a lower speed. This is usually done twice (with a fresh, clean rag each time), followed up with a clean dry rag to soak up solvent left on the cylinder.

Mike

Thank you for your suggestion. We have a similar setup here and I will give this a try. I believe it will help.

Best,

A. Kurti