On February 4, the market price of phthalic anhydride in East China showed a weak consolidation. The mainstream quotation for phthalic anhydride produced via the ortho-xylene method was 6,000–6,200 yuan/ton, while the market price for phthalic anhydride produced via the naphthalene method ranged from 5,550 to 5,900 yuan/ton. The price of industrial naphthalene fluctuated and declined, while the price of ortho-xylene remained stable, leading to a decrease in the production cost of phthalic anhydride. The downstream plasticizer market experienced fluctuating declines, with plasticizer manufacturers maintaining low and stable equipment operating rates. Downstream demand was primarily driven by rigid procurement needs, with phthalic anhydride purchases being mainly demand-based. Consequently, the demand support for phthalic anhydride weakened. Phthalic anhydride manufacturers maintained stable equipment operating rates, ensuring sufficient supply. Phthalic anhydride inventories remained low. It is expected that the future market for phthalic anhydride will continue to exhibit weak consolidation.