Item | First grade | Superior grade |
NaHSO2·CH2O Content% | 98% min. | 99% min. |
State of Solution |
Be soluble in water and appear in clarification or micro turbidity |
Be soluble in water and appear in clarification or micro turbidity |
Sulfide | Not in dark | Not in dark |
Alkalinity as sodium carbonate | 3.0% max. | 1.5% max. |
Odor | Slight | Slight |
Cu & Mn | 5ppm max. | 3ppm max. |
Sodium Formaldehyde Sulfoxylate, commonly known as SFS, is a white crystalline powder used as a reducing agent. It is widely applied in textile printing, dye removal, polymerization inhibition, and paper bleaching due to its stable and controlled reducing power.
SFS is commonly used in the textile, paper, leather, and plastics industries. It is especially favored in vat dyeing, discharge printing, and recycling processes where selective reduction or decolorization is needed.
SFS is usually applied in concentrations ranging from 2 percent to 10 percent, depending on the process requirements. For discharge printing, a 5 percent to 7 percent solution is often sufficient. In color stripping or reduction, the concentration may be adjusted based on fabric type and dye load.
Yes, SFS is considered safe when handled properly. Although it has low toxicity, personal protective equipment such as gloves, masks, and safety glasses is recommended during handling to avoid skin or eye contact and dust inhalation.
SFS should be stored in a cool, dry, and well-ventilated place. The packaging must be sealed to prevent moisture absorption, which can reduce product performance. Avoid exposure to direct sunlight, high temperatures, and incompatible chemicals such as oxidizers.
Under proper storage conditions, SFS typically has a shelf life of 6 to 12 months. To maintain its effectiveness, it is important to use older stock first and avoid repeated exposure to air or moisture.
Yes, in many cases SFS can replace sodium hydrosulfite, especially in applications where a more stable and less aggressive reducing agent is desired. SFS offers better storage stability, lower odor, and easier handling while still providing reliable reducing performance.
When used correctly, SFS breaks down into non-toxic, water-soluble compounds. It generally does not leave harmful residues, making it suitable for processes that require clean finishes or environmentally safe outputs.
Purity is typically measured by titration to determine the active content, which should be above 85 percent in standard grades. Additional testing can include pH value, moisture content, and insoluble matter analysis, depending on application needs.
For technical questions or application advice, it is best to contact the product supplier or manufacturer directly. They can provide detailed specifications, handling guides, and compatibility recommendations for your specific use case.
Wuxi High Mountain Hi-tech Development Co., Ltd is a professional industrial company engaged in special
chemical production, technology research & development, and import & export. The company focuses on
the production, trade, and research & development of various chemical products.
Efficiently treating our customers as partners with sincerity, specialization and satisfaction is our managerial
principle. Attributed to the backup of a dedicated technical team, filled with wide and profound knowledge
and practice in chemicals and world trade for 20 years, the company owns rich experience in product quality
control, technical solution, chemical logistics organization, packaging optimization, port operation, etc., which
accounts for its first-class cost control management and ensures to maintain the overwhelming competitive
advantage over others. In line with the principle of sharing the preferential cost and joint development, the
company has formed an interesting community for years with its customers at home and abroad. Sincerely
to build up a pleasant mutual trust, cooperative, win-win, and value-added sustainable partnership is what
we are achieving to grow together with you!
Since its establishment, the company has been concentrating on constructing an international marketing
network and optimizing supply chain management, where we have established a long-term strategic
cooperation relationship with numerous large enterprises at home and abroad. Relying on our wide business
channels and professional experience, we are more skillfully providing products of stable but differentiated
quality, along with flexible, highly efficient & considerate service to satisfy our partner at more competitive pricing.
![]() |
![]() |