Answer:
At the mill, the corrugated is pulped and blended with additional pulp from wood chips. Broken, thus shorter and weaker, old fibers are blended with the new pulp to make the medium. Recycled paper fibers and new pulp are blended to make linerboard. Then the medium and the linerboard are shipped to a boxboard plant, where the manufacturing process is finished. The medium is corrugated by specially-geared machines, the linerboards are glued on, and the resulting flat pieces, called mats, are trimmed to size and creased along a pattern of folds. The mats are shipped flat to customers who set them up into boxes. Then the boxes are used to package products for shipping.