China had paper before the Western Han Dynasty. 105. In the Eastern Han Dynasty, Cai Lun improved papermaking, and made paper easy to write with cheap and accessible raw materials such as bark and hemp. Papermakers are called "Cai Hou Paper". During the Wei, Jin, Southern and Northern Dynasties, the paper-making technology made remarkable progress, the whiteness of paper increased, the surface was smooth, the texture became thinner, and the paper output increased greatly. Luoyang in the north, Chang 'an in the south, Jianye and Yangzhou in the south are all famous papermaking centers. During the Tang and Song Dynasties, the producing areas of papermaking increased rapidly. Bamboo paper and leather paper became the main varieties.