Managing variables associated with the substrates you use is critical to quality. Find out how to work with some popular, but picky, materials.
Cleanliness is critical. Schedule tasks for cleaning the inside of dryers, and wear hair covers and gowns to prevent contamination. Incorporate good static-electricity controls, along with a controlled environment with humidifiers and air conditioning.
Establish good press checks prior to running the job to check for ink cure and adhesion. Have good control of pre-matching inks in your ink lab prior to printing, and have all controls in place to ensure inks matched in the ink lab are the same when printed on the press.
For printing on polycarbonate and polyester substrates, our best markets are automotive, medical (Figure 2), appliance, controllers (Figure 3), aerospace, solar, and RFID.
Poor screen stretching, improper curing, or poor imaging of the screens can lead to image distortion. Poor curing, wrong mesh count, or incorrect choice of ink can cause ink delamination. Careless handling leads to scratching and denting. Improper curing and excessively thick ink deposits result in ink fracturing during embossing and can cause actuation failures. Finally, improper curing can create unexpected color shifts.
In printing on Luan board substrate (Figure 4), find a supplier that understands the actual use of the material and the application for the P-O-P market. Our supplier picked out the flattest board he had and then sanded the edges to reduce the risk of damaging our screens. You have to keep an eye on board quality and surface flatness, as problems in these areas can lead to ripped screens, dot loss, and image loss. The best markets for this material are old-fashioned restaurants, hardware stores, and building-supply companies.
We also print on polyethylene (Figure 5). In printing this substrate, use films that lay flat without rolling, apply proper vacuum, and use static eliminators. The best markets for this substrate are retail environments and fast-food chains. The best application is outdoor advertising.
Problems with this substrate come up when printing with UV inks. The material is very unstable when exposed to heat. It expands after heating and then contracts—but not always to its original size. Sometimes polyethylene is difficult to run on a single-color press.
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