by clicking the arrows at the side of the page, or by using the toolbar.
by clicking anywhere on the page.
by dragging the page around when zoomed in.
by clicking anywhere on the page when zoomed in.
web sites or send emails by clicking on hyperlinks.
Email this page to a friend
Search this issue
Index - jump to page or section
Archive - view past issues
FLEXO Magazine : May 2012
As an example, Pritchard placed a photo of two Pantone fan decks under black light and the results clearly showed that the paper used in the Pantone GOE system swatch book contained more OBAs than his conven- tional Pantone spot color swatch book. Pritchard explains that newspaper printers use inks that contain OBAs to compensate for poorer quality newsprint that isn’t very white. Anyone who speci- fies the use of such inks should recog- nize that they typically shift color over time as the OBAs fade. They shouldn’t be used for products that are expected to have a long shelf life. Technical experts working on ISO 13655 have recognized that more of today ’s printed materials glow to some degree when they are exposed to differ- ent viewing lights. But, many hand-held spectrophotometers used in the graph- ics arts industry weren’t designed to measure this aspect of fluorescence. The disconnect between existing instrumen- tation and the need to colormetrically match new printed materials containing OBAs explained the growing problem of poor correlation between measurement and visual assessment in supply chains. When the use of OBAs in paper stock and films became widespread, the correlations started to deteriorate due in part to the variation in the amount of ultraviolet light from Illuminant A lamps and the lamps commonly used in view- ing cabinets. While manufacturers of color mea- surement instruments work to provide so- lutions for better correlations of projects printed on substrates containing OBAs, the ISO committee recommended four measurement conditions called M0, M1, M2 and M3 to help reduce confusion in the graphic arts industry. Companies at every link in the supply chain now have a standardized way to share with each other how they took their measurements. MEASUREMENT CONDITION M0 The ISO standard states that mea- surement condition M0 should be used by companies when they are measuring the color and appearance of projects that are printed with inks on substrates where neither fluoresce. Companies can take measure- ments for M0 with spectrophotometers equipped with incandescent lamps that closely match Illuminant A—the most common type of spectrophotom- eters and lamps in use today in the www.flexography.org may 2012 FLEXO 53 BETTER TOGETHER CyberXtendTM Makes It Easy to Combine Multiple Jobs onto the Same Press Run Vibrant Process Reproductions Inventory Reduction Reduced Ink Waste Faster Turnover