This analysis is based on the latest spot average data and the mean difference analysis framework. On September 22, 2026, the mean differences for the three periods of phthalic anhydride decreased compared to the previous day, coupled with a collective reduction in quotes from major Chinese producers. In the short term, the price of phthalic anhydride is in a clear downward trend. Currently, the price of phthalic anhydride is in the high range of the past year, with limited room for further increases. Market participants should pay close attention to the subsequent impact of changes in the supply of upstream raw materials and the operating rates of the downstream resins industry.
Data Explanation
The latest available data is up to September 22, 2026. It is recommended to refer to real-time data.
I. Table of Finite Differences
| Mean Difference Indicator | Value as of September 22, 2026 | Value as of September 21, 2026 | Direction of Change |
|---|---|---|---|
| 5-Day Mean Difference (D5) | -100 | -80 | - |
| 10-Day Mean Difference (D10) | 3.33 | 33.33 | - |
| 20-Day Mean Difference (D20) | 255.84 | 290 | - |
II. Signal State Determination
The current three differences have changed in the same direction as the previous day, all being negative, which is a clear signal of a decline.
III. Conclusions on Trend Directions
The short-term phthalic anhydride price trend is clearly downward. Reason: According to the mean‑difference method, the changes in the 5‑day, 10‑day, and 20‑day moving averages all moved in the same direction as the previous day—downward—and were all negative, meeting the criteria for a clear downtrend. Meanwhile, on September 22, mainstream Chinese phthalic anhydride producers broadly lowered their spot‑market quotes: Zhenjiang Liancheng and Tongling Chemical both cut prices by RMB 100 per ton, while Changzhou Xinyang reduced its quote by RMB 50 per ton. Actual transaction prices followed suit, further reinforcing the assessment of a declining trend.
4. Spatial Reference
The current phthalic anhydride price is in the highest 20% range of the 60-day, 3-month, and 1-year cycles, corresponding to the 5th level (high position) out of 5 levels, with limited room for further increase.
V. 1-Year Trend Chart
VI. Risk Warning
The above analysis is for reference only and does not constitute trading advice.
(Source: )
