As of October 29, 2026, the spot price of phthalic anhydride in China remained at a high level. The over-sold inventory of suppliers provided some support to the prices. However, according to quantitative calculations using the average difference method, the current price of phthalic anhydride is in a rebound phase within a volatile trend, showing bearish signals. Moreover, the price is already in the high range of the past year's cycle, with limited room for further increases. It is recommended to closely monitor the demand follow-up pace in downstream sectors such as unsaturated resins and plasticizers.
I. Table of Finite Differences
Data cut-off date: October 29, 2026; data source:
| Mean Difference Indicator | Today’s Value (2026.10.29) | Yesterday’s Value (2026.10.28) | Direction of Change |
|---|---|---|---|
| 5-Day Mean Difference (D5) | 53.33 | 76.66 | - |
| 10-Day Mean Difference (D10) | 31.67 | 18.34 | + |
| 20-Day Mean Difference (D20) | 64.16 | 80.83 | - |
II. Signal State Determination
When the three successive divided differences change in the sequence (−, +, −), the corresponding signal is a pullback (bearish).
III. Conclusion on Trend Direction
The current phthalic anhydride price trend in China is fluctuating (with a bearish bias). The reason for this judgment is that the changes in the three average differences from the previous day are not entirely consistent, which does not meet the criteria for a clear upward or downward trend, indicating a fluctuation range. Additionally, the signal combination corresponds to a bearish rebound characteristic.
Fundamental Supplementary Verification: The mainstream manufacturer in Changzhou, XinYang, is operating normally with its phthalic anhydride plant, and the inventory is oversold. The factory increased its ex-factory quotes for three consecutive days from October 26 to 28, 2026. Currently, orders are being accepted on a limited basis, and there is some support for prices in the short term.
IV. Positional Space Reference
Phthalic anhydride prices are at high levels for 60-day, 3-month, and 1-year periods, corresponding to the 5th tier (the highest 20% range within the cycle) out of 5 tiers, with limited room for further increases.
V. 1-Year Trend Chart Display
VI. Risk Warning
The above analysis is for reference only and does not constitute trading advice.
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