paper

Evidence

"the Abbasid caliph Hārũn al-Rashĩd (170/786–193/809) substituted the use of paper for parchment in the chancery as it was more difficult to erase a text written on paper or to scratch it out without this being noticed"

Remarks

Paper was preferred over parchment because it offered better security against forgery (tazwir). On parchment, text could be erased or scratched out more easily without detection (p. 108). The text also mentions a technique called ta'tiq, which involves treatments to make paper look old, described in the treatise 'Umdat al-kuttab (p. 109).