Tips for Digitally Printing & Laminating Top-Coated Polycarbonate Films
RTape’s Claritex® 10 mil bright white velvet-matte polycarbonate films feature a specially formulated ink-receptive coating for solvent, ecosolvent and latex inkjet printers. The good hold out characteristic of the top coating keeps the colorant of the ink on its surface for brilliant color reproduction. The coating also quickly absorbs the ink, which prevents bleeding and maintains the integrity of the dot structure for superb print sharpness. Its fast absorption of ink also promotes fast drying times for unimpeded output.
Test, Don’t Guess.
Before running a job in production, you should evaluate Claritex® top-coated polycarbonate films for compatibility with the inks, backer films, overlaminates and transfer adhesives. You should also test samples under the same lighting conditions in which the finished product will be used. My story, Maintaining Color Quality & Uniformity, explains how colors can change in appearance under different lighting conditions.
Prior to applying a backer film or overlaminate to the printed image, it is critical that the ink is thoroughly dry. Several factors can affect drying times, including printing environment, ink formulation and ink saturation. Ideally the ambient shop temperature should be approximately 21º C (70ºF) at 50% RH.
Ink Saturation.
If you want to reproduce bold, rich colors, you need a good deposit of ink. Without the right ink setting, you potentially could not reproduce a full range of the color gamut. Not printing enough ink results in a print that will look washed out.
Printing too much ink, however, is as bad as printing too little. Ink saturation should not exceed 270% to 300%. High ink densities can result in print problems. Over saturation of ink can cause the ink to bleed. Also with dot gain, the individual ink droplets can bleed together or coalesce, resulting in the loss of contrast and image definition. As ink dots bleed, the hue of a color can also change.
While the top coating on the polycarbonate film is designed to absorb a heavy ink load, its ability to absorb ink has a limit. Once that limit has been exceeded, the print often exhibits a defect that looks as if the ink has crinkled.
Printing Mode.
To ensure optimal printing results, we recommend printing in the unidirectional print mode. When printing on clear Claritex polycarbonate films for backlit applications double strike printing may be required so the print would not wash out when a backlit display is illuminated. When printing on the white Claritex film, the single strike setting is typically used.
Heat settings should not exceed 38º C (100ºF). High heat settings can distort the film, which can result in head strikes. Printer settings, however, will vary from one brand of printer to another, and from one shop environment to another.
Profiles.
Printing with generic profiles for glossy vinyl and for frontlit/backlit films usually produce acceptable results. Profiles for Premium Backlit Film and Premium Cast have been used successfully.
Printable Claritex® polycarbonate films are compatible with Eclypse™ polycarbonate overlaminates. To make a rigid tradeshow booth panel laminate the printed graphic with either a 10 mil or 15 mil polycarbonate overlaminate. In constructing header panels or laminating posters use a 10 overlaminate. Use the 10 mil media with a 3 mil or 5 mil laminate for headers and end caps.
Polycarbonate overlaminates are tougher than other laminating films. Used for tradeshow applications, you can roll and unroll these graphics show after show. They will provide long term durability, if the graphics are rolled properly, image side to the outside.
Storage.
Store rolls in their original packaging either vertically or horizontally. After opening, use polycarbonate films within six months.
Applications.
Printable polycarbonate films are an excellent choice for tradeshow graphics and booth panels, retractable banner stands and Point-Of-Purchase posters and displays.
