On February 3, the phthalic anhydride market in Shandong region experienced a weak consolidation. The mainstream negotiated prices for ortho-xylene-based phthalic anhydride were between 6,000 and 6,200 yuan per ton, while those for naphthalene-based phthalic anhydride ranged from 5,550 to 5,900 yuan per ton. The price of raw material ortho-xylene remained stable, while the price of industrial naphthalene declined, leading to a reduction in the cost of phthalic anhydride. Downstream plasticizer prices fluctuated downward. Phthalic anhydride production facilities maintained stable operations, with plant operating rates remaining low and steady. The supply of phthalic anhydride in the market tightened, while the operating load of plasticizer enterprises remained temporarily stable. The support from rigid demand for phthalic anhydride weakened, and the market outlook is expected to continue its weak consolidation trend.