Tips on Paper

Digital printing, also known as variable-data printing (VDP), computer-generates a new image for each impression. This means faster turnaround times and lower production and setup costs. Digital printing uses toner and inkjet technology and has almost zero makeready—no proofs or setups. Very short runs, collations, and personalized “one-to-one” promotions are produced cost-effectively, in virtually any size format. Digital printing is also referred to as Short-Run printing and On-Demand printing.

The image and/or text data is input into a computer by a scanning camera or word processor. The data is converted to the appropriate file format, the layout is finalized, and it’s ready to print. Data can be changed “on the fly.” Because toner and inkjet behave differently than ink, they usually require special papers. Some paper manufacturers offer grades for both digital and offset litho, so that jobs can include sheets printed by both processes.

Digital images can be produced in virtually any size. Very large graphics can be “Tiled” and reassembled. The largest sheet size for sheetfed printers is about 14 x 22 inches, and the largest image area for roll-fed printers is 19 inches by several feet. Most handle 8.5 x 11-inch and 11 x 17-inch sheets with ease, and some can handle 12 x 18-inch sheets either through the tray (lots of sheets) or bypass area (fewer sheets).

Color graphs / charts
Short run, variable-data jobs
Photo-quality images (high-resolution)
Packaging
Labels, especially VDP
Wide format banners
Posters
Fleet graphics

Inkjet
Inkjet printing is designed mainly for home, home office, and small business use, but is becoming increasingly common for commercial applications. Inkjet printers are inexpensive and produce good color output, but can be slow. For best results, use papers specifically designed for digital inkjet technology—with optimized smoothness, sizing, sheet formation, special coating, or enhanced brightness. Domtar Microprint InkJet features a smooth, closed surface to reduce feathering for a crisp, bright image. Files must be finely adjusted for optimal print results. Four-toner color printers have a better color gamut than some four-color offset presses. One digital color press has a five-color version to extend the gamut, and liquid toner presses have seven-color capability for spot colors.

Inks
Inks for drop-on-demand inkjet printing are pigment-based rather than dye-based. This means they are water-soluble and therefore less permanent than inks used in offset printing or toners used in laser printing (electrophotography). Non-water-soluble, lightfast inks are now available for industrial use. Combined with fade-resistant papers, they enhance photo longevity and color fastness. Some printers feature a custom color match (Pantone Matching System – PMS) for high-resolution jobs. Printers can also provide a color chart to designers.

Thermal Wax
Thermal wax printers produce vibrant color but require very smooth or specially coated paper or transparencies for best output. They are used for large runs of transparencies for business presentations.

Dye Sublimation
Dye sublimation heat-vaporizes the dyes so the colors permeate the paper surface, for a gentle gradation at the edges of each pixel instead of the conspicuous border produced by inkjets. Color is also less vulnerable to fading and distortion over time.

Electrostatic
Electrostatic forces form the image directly on the printing surface using dry or liquid toner to produce lightfast, fade-resistant images. Powder-based toners require paper that will hold or transmit an electrical charge. Liquid-based toners might also require specially coated papers for some applications.

Spray Jet
Similar to the Inkjet process, but the ink is applied to the substrate using spray nozzles.

Continuous Flow Inkjet
Mainly used in industrial applications where print quality is not crucial, e.g., production line labelers and packagers (lot numbers, production dates, etc.).