Filtration, Print Quality, and Anilox Scoring

Filtration is an area that does not often get enough attention. Ink with everything in it, from unidentifiable lumps to part of someone's lunch, will not print the way you and your customers want. Metal blades will shed particles. Dried ink, especially water ink, is very abrasive. Ceramic from the anilox itself can easily score a roll. Clean ink will go a long way in helping to provide good consistent print quality. That's where the importance of a good filtration system comes in.

Always use a quality filter on the pump discharge. The filter cartridge should be made from a non-corrosive material such as stainless steel and have the correct mesh screen. Meshes available include 30, 60, 100, or 150. Select a mesh that will filter out the unwanted contaminants but will not clog too quickly (the most common excuse we hear for not using ink filters is that they get too full too quickly This also means you have a lot of contamination in your ink and really need filtration.). At the end of a run, just pull out the filter cartridge, and all the debris comes with it for easy disposal and quick changeovers. Some filters also self-drain when the pump is shut off, eliminating the mess of a housing full of ink.

It is critical that any good ink filtration system includes a magnet to further reduce the potential of anilox scoring. With chamber systems, any contamination that finds its way under a doctor blade can cause scoring, but metal contaminants are especially dangerous. Add a high power rare earth magnet to your ink filtration system and you'll pull even the smallest metallic particles remaining in the ink. You can sometimes select a magnet that can be retrofitted to the lid of your existing filter module or you can get a hanging bracket which fits over the edge of your ink container. If choosing the hanging bracket option, it is best to have an adjustable bracket that allows you to set the magnet at the desired level in the ink container. Cleaning options for magnets can come in two types. Some have a "cleaning sleeve" that you slide down the magnet when it becomes too dirty. The problem with this option can be that you still have to clean the sleeve and often we see the sleeves getting lost. Graymills megaMag is stainless and tapered at the bottom end. The magnet stops above the tapered end, so metal particles wipe right off.

A good filtration program can give you better print quality, and a roll without scoring will print better. You'll also save a lot of money by not having to recondition rolls as frequently.

For more information on this issue, please contact: info@teamflexo.com

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