Jacron

Jacron is a type of paper material that exhibits similar characteristics to animal-derived leather. It is sustainable, durable, and less expensive and hence is used in place of leather for the rear patch on the waistband. The material is also used to make clothing, footwear, and accessories. 

Levi's jeans was the first to use it in 1954. Until then, Levi's and other makers used leather for the patch. 

Although jacron simply means a leather-like material, the word has become synonymous with the back leather patch on the jeans because of its predominant use for the back patches. However, many jeans makers continue to use high-quality leather for their premium jeans.