The use of six and seven-colour sets in packaging print -- an approach which is rapidly gaining ground in the UK -- could be halted by legal action over patented systems.
Michael Wilcox, md of Bristol's School for Colour, says he developed a system of six specific colours over some 20 years, initially with a view to ensuring faithful print reproduction in his own art books. These colours, which can be combined to produce any shade required, were then closely defined in a patent. Subsequent approaches to ink and software companies were safeguarded with non-disclosure documents, he adds.
Recently, Wilcox has seen examples of packaging appearing in supermarkets apparently using a version of this exact system. "I think I'm being ripped off in a major way," he says, "and no one involved wants to talk about it. I suspect the people I've spoken to in the past feel they've found a way around the patent."
The alleged patent infringement is now in the hands of Wilcox's solicitors. The outcome, he claims, will either be some sort of financial settlement, or else an injunction on the use of particular inks.
"Stopping that tonnage of inks going out to printers every day will cause a lot of problems," he says.
At least one leading UK flexible packaging supplier did not want to discuss its use of specific colour sets when approached by Food Manufacture. Currently, a number of converters are said to be using the same colour set for one particular major brand.
Wilcox warns that, according to the advice he has been given, everyone in the supply chain is potentially liable for prosecution if a patent has been infringed.
Equipment suppliers confirm that major UK converters are now using seven colour sets (six colours plus black) to achieve up to 90% of the colour gamut.
The technology means that different pack designs can be printed in parallel on the same press, and changeover times can be dramatically reduced.
Tom Wiltshire, director at press supplier Wantzen, says: "I see these techniques being used on long runs. The benefits are that you can use combination plates, for different snack flavurs, for example, on the same run." The result is greater flexibility in production and, potentially, reduced costs for packaging.
But Dr Tim Claypole, head of printing and coating at the University of Wales, Swansea, cautions: "Printing has survived by being a black art. If you're going to use seven colours, then it has to become a precise science."