Impact of Rising Sulfur and Sulfuric Acid Prices on Fluorescent Brightener OB-1

Over the past year, domestic industrial sulfur and sulfuric acid prices have increased dramatically. Affected by disrupted global supply chains, unbalanced supply and demand as well as policy adjustments, these two fundamental chemical raw materials have experienced a trend of steady growth, sharp surge and slight pullback at high levels. As key materials for the fine chemical industry, their price hikes have passed down the industrial chain, driving up the overall production cost of **Fluorescent Brightener OB-1** significantly, which has become the core factor affecting the price of Fluorescent Brightener OB-1. This article analyzes the price correlation between upstream raw materials and Fluorescent Brightener OB-1 based on price trends, reasons for price increases, supply and demand status, production techniques and raw material consumption.

1. Price Trends of Sulfur & Sulfuric Acid and Causes of Price Hikes

From June 2025 to June 2026, domestic sulfur prices rose remarkably in three phases. The average transaction price went up gradually from 2,475 CNY/ton to 3,850 CNY/ton in the second half of 2025, with a growth rate of about 55%. Starting from 2026, sulfur prices soared rapidly. It exceeded 5,900 CNY/ton in March and peaked at 11,600 CNY/ton in early June, rising by over 210% compared with the start of the year. In mid-June, the price dipped moderately to 9,300 CNY/ton, still staying at a historic high. ### Domestic Industrial Sulfur Price Trend (Unit: CNY/ton) ``` 12000 |                                        ● 11600 (Early June, Peak)      |                                       / 10000 |                                      /      |                                     / 8000 |                                    /      |                                   / 6000 |                          ● 5900 (March)      |                         / 4000 |                ● 3850 (December)      |               / 2000 |   ● 2475 (June 2025)      |____________________________________________________         Jun.25  Aug.25  Oct.25  Dec.25  Feb.26  Apr.26  Early Jun.26  Mid Jun.26 Time Note:

Jun.2025 - Dec.2025: Steady growth;

Jan.2026 - Early Jun.2026: Sharp surge;

Mid Jun.2026: Slight correction to 9,300 CNY/ton

Sulfur is the main raw material for sulfuric acid production, so their prices are closely linked. Multiple factors jointly push sulfuric acid prices higher. First of all, over 60% of domestic sulfuric acid is produced from sulfur. The rocketing sulfur prices directly lifted production costs of sulfuric acid. Secondly, global sulfur supply is tight. More than 90% of sulfur is a by-product of oil and natural gas refining with limited capacity expansion. Geopolitical conflicts blocked shipping in the Strait of Hormuz, while Russia continued the sulfur export ban. China's sulfur import volume plummeted by 72.39% year-on-year in April 2026. Thirdly, downstream demand from phosphate fertilizer, lithium iron phosphate and hydrometallurgy keeps growing. Meanwhile, the output of by-product sulfuric acid from copper smelting decreased due to tight copper ore supply. Besides, China tightened the export policy for industrial sulfuric acid, further supporting its high price.

2. Global and Domestic Supply & Demand of Sulfur

China relies on imports for 56% of its sulfur consumption. Domestic sulfur is mainly the by-product of refineries and natural gas plants, which cannot increase output in a short time. Affected by reduced imports, the sulfur inventory at major domestic ports dropped from 2 million tons to 1.02 million tons, only enough for around 20 days of consumption. In terms of demand structure, phosphate fertilizer industry accounts for 60% of total sulfur consumption, new energy industries 22%, fine chemicals including **Fluorescent Brightener OB-1** 12%, and other industries 6%. Domestic Sulfur Downstream Demand Distribution Phosphate fertilizer: 60%     ■■■■■■■■■■■■■■■■■■ New energy industry: 22%     ■■■■■■■ Fine chemicals (including Fluorescent Brightener OB-1): 12%  ■■■ Others: 6%                    ■ The market has long been in short supply, which underpins the high sulfur prices.

3. Application and Consumption of Sulfur & Sulfuric Acid in Production of Fluorescent Brightener OB-1

Fluorescent Brightener OB-1 is widely used in chemical fiber, plastics and coatings. Domestic manufacturers mainly adopt the sulfur-based production process. The whole production has three procedures. No sulfur is used in the condensation stage for intermediate synthesis. In the core vulcanization process, the intermediate reacts with industrial sulfur at 255-265℃ for 3 to 4 hours to form the molecular structure of Fluorescent Brightener OB-1. To produce one ton of finished product, 2.0 to 2.2 tons of industrial sulfur are required. In the follow-up desulfurization and refining, a large amount of sulfuric acid is used for washing and recrystallization. The huge consumption makes the production cost of Fluorescent Brightener OB-1 highly sensitive to the price changes of sulfur and sulfuric acid.

4. Price Changes of Fluorescent Brightener OB-1 Driven by Raw Material Hikes

The price of Fluorescent Brightener OB-1 has moved in line with sulfur and sulfuric acid prices over the past year. From June to December 2025, raw material prices rose mildly. With normal operation rates, manufacturers raised product prices slightly. From January to early June 2026, the skyrocketing raw material costs squeezed corporate profits sharply. Shortage of sulfur also forced some small and medium-sized factories to cut production, leading to tighter spot supply. As a result, the price of Fluorescent Brightener OB-1 surged rapidly. In mid-June, sulfur prices fell back slightly, while the price of Fluorescent Brightener OB-1 remained at a high level. Manufacturers were still digesting high-cost raw materials purchased before, and stable downstream demand also prevented price declines.

5. Conclusion and Market Outlook

Sulfur and sulfuric acid are essential raw materials for producing Fluorescent Brightener OB-1, forming a strong price linkage along the industrial chain. The current global sulfur supply gap cannot be filled in the short term, and geopolitical and shipping risks still exist. Sulfur and sulfuric acid prices are expected to stay high. Under such circumstances, Fluorescent Brightener OB-1 will continue to face cost pressure, and its price will remain firm in the near term. In the long run, its price trend will still follow the fluctuation of upstream raw materials. Relevant enterprises shall keep a close watch on raw material prices and inventories, and arrange procurement properly to avoid market risks.