Screen Printing - December 2012/January 2013 - (Page 4)

SOLUTION SOURCE BOOK PREPRESS FOR SPECIAL-EFFECT GARMENT PRINTING ecorating garments with special-effect inks can be a daunting task when you don’t have everything in place in prepress. These tips will assist you in building reliable and repeatable processes and procedures. Designing for the print Becoming familiar with how special-effect inks work is critical to printing them successfully, no matter how long the job run. Experimentation aids in determining how special-effect inks will appear on finished garments, given your shop’s equipment and practices. An ink’s features play a big part in how much it should be incorporated into a design. A high-density ink might work best when used to accentuate smaller or finer design elements, while specialized decorating materials—caviar beads and flock, for example—might not work as effective on smaller designs or graphics that feature very fine lines. Decorative products such as these don’t provide enough surface area to create a visible effect. Design elements to which special-effect inks are applied must be sized appropriately to take full advantage of the refractive, textural, or other quality the inks impart. Similarly, design considerations come into play when using inks that change dimensionally. Let’s use puff ink as an example of such an ink. The artist may need to build open space into a design to accommodate the desired expansion of the puff. In addition, when puff is overprinted, its expansion will raise, texture, and lighten the overprinted colors. Large areas of puff can bend or curl, while thick layers of the ink can expand unpredictably and inconsistently, particularly when lots of puff additive is used. In general, the best way to create artwork for specialeffect printing is to think about the printing process in reverse D order: curing, printing, prepress, and design creation. Examining the workflow in reverse will allow you to identify your limitations in each step and then make adjustments in preceding steps to make up for those limitations. Colors and print order Specialty inks are often printed last in the sequence, particularly those that rise beyond the substrate surface. They are up last because they can interfere with the printing of other colors that may be printed close to the raised edges. However, overprinting raised areas can sometime yield interesting and unique effects in finished prints. Print order can influence many aspects of a design, including the actual number of colors available on press. Some special effects require that the garments undergo additional processing steps after printing—some of which necessitate the removal of garments from the press before the specialty ink or coating is applied. Caviar beads, flocking, metallic flakes, and large glitter are often applied off-press to printed adhesives or on one of the last print positions on press. Specialized press attachments are available for some of these products, but most shops rely on labor-intensive, off-press methods, at least at first, to become familiar with adhesive-locked materials. Ink color and opacity You can generate creative effects when using some types of specialty inks as underlay colors that are then overprinted with conventional formulations. Communicate the desired effect to the production staff, and choose the appropriate combination of underlay and overprint colors. Using flake-bearing or reflective inks as an underlay, for example, can lead to attractive designs with a deep, layered look. However, the overprinted color must be translucent so that light can penetrate the ink and reflect light from the metal- FIGURE 1 Using mesh with openings that are two to three times larger than the diameter of the particles in the specialty inks you print will prevent clogging on press. FIGURE 2 Embedding at least half the bead diameter in adhesive yields optimum washfastness when working with caviar beads. 4 SCREENPRINTING

Table of Contents for the Digital Edition of Screen Printing - December 2012/January 2013

Screen Printing - December 2012/January 2013
Contents
Prepress for Special-Effect Garment Printing
Tips for Optimum Screen Exposure
Maximizing Image Size and Position
Understanding Screen-Tension Loss
A Look at Screen Lift-Off
Staging Garment-Printing Jobs
How to Control Dye Migration
Fine Tuning for Fine Details
Application-Specific Considerations for Graphics Printers
Upping the Ante at SGIA 2012
Statement of Ownership
U.S. & Canadian Directory
Opportunity Exchange
Advertising Index

Screen Printing - December 2012/January 2013