On March 13, the trend of the phthalic anhydride market in Shandong was temporarily stable. Downstream factories maintained just in need of purchase, while high-end transactions were blocked. The main trend of the on-site ortho-phenyl method source negotiation was 8600-8700 RMB/ton, and the main trend of naphthalene method source negotiation was 8300-8400 RMB/ton. The on-site merchants' devices operated stably and the sales situation was general.