US Patent Issued to Eska on June 24 for "Process for producing coloured cardboard in a cardboard production apparatus, and coloured produced by such a process" (Dutch Inventor)

ALEXANDRIA, Va., June 25 -- United States Patent no. 12,338,580, issued on June 24, was assigned to Eska B.V. (Sappemeer, Netherlands).

"Process for producing coloured cardboard in a cardboard production apparatus, and coloured produced by such a process" was invented by Albertus Uil (Wildervank, Netherlands).

According to the abstract* released by the U.S. Patent & Trademark Office: "According to the invention, in producing coloured cardboard, carbon dioxide is injected and dissolved in a mixture of pulp and at least a sulphur dye, while the mixture is pumped with a delivery pressure higher than 200 kPa out of a first pulp reservoir (11) towards a second pulp reservoir (12), and in such manner that the mixture is acidified by the carbon ...