Installed last year as part of a £25m investment in the Dundee-based publisher’s Kingsway printing facility, the Colorliner, which was specified in an eight-tower configuration, was signed for in 2011.

The equipment was commissioned in November with initial daily runs of 80,000 copies of The Courier and 30,000 of the Evening Telegraph, printed in cold set.

In January Goss Ecocool heatset dryers were commisioned on the CPS, which, according to the company, allows it to “print a commercial quality product”.

The royal couple, known in Scotland as the Duke and Duchess of Rothesay, were given a tour of the newly refurbished facility, meeting production staff and starting the new equipment to officially mark its full commissioning.

A DC Thomson spokesman said: “We were delighted to welcome The Duke and Duchess of Rothesay to our Kingsway plant. Their Royal Highnesses toured the presses and met with staff members from across our publishing business, in particular production.”

To mark the occasion, a special edition of DC Thomson’s The Beano, out on 15 June, will feature the Duke and Duchess with Prince Charles illustrated in a Bash Street Kids strip and the Duchess in a Dennis the Menace and Gnasher strip opening a new school library.

Beano editor-in-chief Mike Stirling said: “We are thrilled to welcome The Duke and Duchess of Rothesay onto the pages of The Beano.

“We’ve had a blast creating their characters and storylines. It’s not every day you get to write Their Royal Highnesses into The Beano – we hope they like it!”