The Best Paper for the Job

Synaps OM and Synaps Digital XM are examples of products that have similar base sheets but have surfaces that are engineered for different print application methods. While both products start with a biaxially-oriented polyester base sheet Synaps OM is two side coated with a proprietary ink receptive layer that can be offset printed with standard inks and the ink will dry faster than it would on many coated paper stocks. Synaps OM is also Rochester Institute of Technology certified for use on HP Indigo presses. Synaps Digital XM on the other hand is two-sided coated with a proprietary dry toner accepting coating and is specifically designed for use on dry toner printers.

To ensure its customers understand the differences between digital and offset papers, Mohawk has created www.MohawkMakeReady.com, an online resource for all graphic producers The site, which includes video links as well as articles, explains why each printing process requires its own specific substrate. In fact, one of its hot topics is why cutting down offset folio sheets is not a viable option.

Cutting down offset sheets to use in a digital printer can introduce contaminants into your digital device, says Gavin Gaynor, vice president of research and development, Mohawk. Paper that is guillotine-trimmed will often contain more dust and paper bits leading to issues on the printers. Also, there is the possibility that sheets won’t be cut square or won’t be properly separated from each other for feeding. Also to be considered is the importance of grain direction for digital printing, particularly when finishing is involved.

Mohawk Digital Papers—Everyday Digital, Bravo, Via, Navajo, Options, Superfine, Color Copy, and 50/10—are available in popular digital sheet sizes and small rolls.

Coated papers that are built for sheetfed and heatset web offset will not produce acceptable results on digital inkjet web, explains Howard Kirby, Appleton Coated, product manager. Appleton Coated recently introduced Utopia Inkjet—a coated product that features technology developed jointly with HP—for high-speed inkjet web presses. The product line includes both lightweight matte products for the book publishing market and heavier weights in gloss and dull for commercial applications including direct mail.

Some mills are offering digital papers designed to match available offset grades for cross platform production, allowing printers to ensure consistency for jobs that contain offset and digital printing, Mohawk, for example, makes digital products—even envelopes—that match most offset grades.

As digital printing expands into new realms, specialty digital substrates also expand, and now include wide and grand format, pre-converted forms, synthetic sheets, pressure sensitive and magnetic substrates or coatings, says xpdex’s Watson. “Showcase Digital, available through xpedx, is a line of pressure sensitive paper and vinyl manufactured for both toner and HP Indigo application. Web ink jet rolls are now available in different finishes and weights for book publishing, direct mail and commercial print applications.”

All xpedx exclusive digital brands are properly manufactured for optimal performance on specified presses, offering national brand consistency to the printer.

“Using a substrate certified for the specific press is the best way to ensure compatibility between substrate and press,” says GPA's Pergande. “If an incompatible or inferior material is used and runs through the press successfully, there is still the risk that it will not stand up to finishing processes such as UV coating, lamination, folding and scoring. Incompatible materials may not have the moisture content required to withstand the heat of the press and risk cracking when folded or scored. You risk sinking time, money and resources into material that at first may seem like a bargain, but will ultimately cost you in the end when you have to reprint the job.”

TIPS for Choosing the Right Sheets:

(Courtesy of Mohwak papers)

• All press sheets aren’t created equal. They’re designed for specific printing equipment.
• Digital-only substrates are made to precise caliper and moisture levels, and can have surface treatments for dry toner, liquid toner or inkjet applications.
• Risks posed by cutting down litho sheets to use in your digital press include: (1) Introducing contaminants into your equipment, (2) Extra cost — waste, time and labor, (3) Sheets not cut square or won’t easily separate, and (4) Grain direction might be wrong for finishing
• Materials made only for digital — pre-converted forms, synthetics, pressure sesntive materials, magnetics — let you offer more value-added services for a bigger bottom line.