On January 8, the market price of phthalic anhydride in East China showed a strong consolidation trend. The mainstream quotation for phthalic anhydride produced via the ortho-xylene method ranged from 5,900 to 6,150 yuan per ton, while the market price for phthalic anhydride produced via the naphthalene method ranged from 5,600 to 5,850 yuan per ton. The price of industrial naphthalene fluctuated and stabilized, while the price of ortho-xylene fluctuated and increased, leading to a rise in the cost of phthalic anhydride. The downstream plasticizer market experienced a strong upward trend, with plasticizer manufacturers reducing their equipment operating rates. Downstream demand remained rigid, and purchases of phthalic anhydride were primarily based on immediate needs. Despite this, demand support for phthalic anhydride persisted. Phthalic anhydride manufacturers slightly reduced their equipment operating rates, but supply remained sufficient, and inventory levels were low. It is expected that the phthalic anhydride market will continue to show strong consolidation in the near future.