Not only in the past, the anger on paper was not so heavy, because the old paper was left for a long time, and the original paper refers to raw paper. Now painters also like old paper, so they usually use the original paper for freehand brushwork. Because the base paper is not easy to grasp when it meets water, the effect will be stable and excellent, while meticulous painting is done on cooked paper or silk. Old paper generally refers to rice paper that has been put on for several years.
I hope it will be helpful to you and I hope it will be adopted.