Clean Rollers to Remove Glaze

Glaze is caused by the buildup of particles in the mountains and valleys of the roller surface. This gives the roller a smooth surface and makes it unable to convey ink or water, which results in a long list of printing problems.
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The nap of a glazed roller is filled and covered with different particles accumulated from all of the materials that pass over the roller: water-soluble particles (gums, coatings, dust), solvent-soluble particles (inks, etc.), and insoluble residue (mineral deposits, clays, soap deposits). The particles are mixed and bound together, trapping each other into the tiny grooves. To restore the roller, you need to flush all of these particles out of the grooves one step at a time.
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Using water alone won't work, because only the water soluble particles and other particles on the surface would be removed. The same is true for solvent-soluble particles.
Calcium from paper is particularly annoying when it collects on rollers. You will see a uniform white haze develops on the surface of rollers in either the inking or dampening trains. This interferes with the ability of these rollers to carry uniform ink and/or water films, and leads to poor ink transfer, roller stripping or sensitive water rollers. In extreme cases, a hard band of white calcium compounds builds up at roller ends, and roller settings cannot be properly maintained. Regular cleaning eliminates calcium too.
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Cleaning Step 1: Use a water miscible wash (solvent mixed with water) to remove both the solvent-soluble and water-soluble particles that are near the top of the deposit layer. This leaves the insoluble particles.
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Step 2: Use a non-grit roller paste to remove the insoluble particles. Be sure to use a paste that is designed and tested for the type of rollers you have. Never use a paste with grit, for this will damage the rubber. We recommend FEBO 2000.

With the layer of insoluble particles removed, most of the remaining soluble particles will be exposed and can be washed out with a second water-miscible rinse.


Other Cleaning Tips

If you are cleaning the rollers manually, wash 2/3 of the press first, allowing the other 1/3 to drive the rollers.p_wash1
Then wash the other 1/3. This allows you to drive the rollers with no skidding or stopping.p_wash2
Let the solution work into the ink.
Keep wash-up blades like new.
Take time to do a thorough cleaning. It will pay off in better print results and longer roller life.