HydroBlue® 90

As the inventor of the original Hydrosulfite in 1904, BASF has massively improved heritage with the all-new first-choice dyeing product for leading suppliers of premium denim brands.

With long-term stable, odorless, and dustfree dithionite content of 90%, HydroBlue® 90 offers excellent consistent dyeing quality, reliability and efficiency, combined with safer handling.


Sodium dithionite is a reducing agent, added in the yarn dyeing process with the indigo before denim fabric is made. The stable sodium dithionite content of HydroBlue® 90 products ensures an even steadier and more consistent dyeing effect on the yarn to minimize off-specification products along the value chain.

The quality of Hydrosulfite is one of the most important factors for denim manufacturers because faults in denim dyeing are difficult to detect until the jeans have been produced. The quality of denim largely depends on the quality of the Hydrosulfite reducing agent and indigo used.

HydroBlue® 90 was certified with high level of stability. Hydroblue® 90 offers an extralong shelf life of at least two years.

The indigo-dyed yarn may appear more greenish, reddish, dull or pure depending on the ration of sodium dithionite and caustic soda. The smallest variation in terms of sodium dithionite content can affect dyeing results, such as ring dyeing, fastness, and color fixation. With the stable sodium dithionite content in HydroBlue® 90, consistent dyeing results are ensured to reproduce the same shade.

TÜV Rheinland has conducted the analytical conformity assessment at BASF and completed the on-site audit according to ZDHC MRSL Level 3. To achieve this, companies must meet stringent requirements in various areas, including health and safety management, waste and air emissions management including EHS, supplier management, quality management systems and toxicological risk assessment

Specialist Certifier Steffen Tümptner

TÜV Rheinland LGA Products GmbH