The Epson T88 model is a thermal printer. Receipt paper for thermal printers has a chemical coding which makes the paper turn black in heated conditions.
This printer is not optimal in kitchen settings and is not recommended for kitchen printing. The correct type of paper needed is 3 1/8 x 230 thermal paper.
The Epson TM-U220 model is an impact printer and does not have the same issue as the T80 model. Kitchen paper is 3 inch 2-ply carbon less impact paper.