Flexo CtP?Out of the Gates

With benefits stemming from the improved quality of digital plates, CtP for flexo is making its presence known.

by Tom Polischuk, Editor-in-Chief

WITH COMPUTER-TO-PLATE (CtP) technology for flexographic printing nearing its pre-teen years, its benefits are having a significant impact throughout the industry. These benefits are derived from the elimination of film and the on-press efficiencies stemming from improved quality plates.

Frances Cicogna, packaging segment marketing manager for Agfa, points out a major difference between the current state of CtP for flexo vs. CtP for offset. "Computer-to-offset is a direct-image process in which the plate is exposed via the laser. Computer-to-flexo uses a digital mask in which film that is pre-applied to the plate is imaged—the plate is then exposed and processed conventionally."

An array of plate options are available including digital sheet plates that can be processed using chemical-free, solvent-washout, or water washing methods; digital plates for processing 'in the round'; and digital plates that can be processed thermally.

MacDermid Printing Solutions offers a variety of photopolymer plate technologies, including traditional sheet photopolymer, digital sheet photopolymer, digital sheet photopolymer in-the-round, liquid photopolymer technology, and water-washed sheet photopolymer technology. Geoffrey Barba, director of marketing, says the company is continually developing ways to improve both the processing times for these products and the on-press performance.

He also sees the growth beginning to build with digital technology. "Digital plate technology is gaining market share," he says. "The ability to image finer dots helps improve the overall print quality of flexo."

Water-wash digital plates bring along the advantages of both digital technology and water-wash processing. Anderson & Vreeland (A&V) provides CtP systems that "process digital photopolymer plates with an aluminum-based ablative layer that washes out in plain tap water," says Paul Zeinert, product manager for A&V. Benefits include reduced drying time, reduced costs, and excellent ink transfer.