Metalworking Fluid Additives

CONTRAM™ ST-1 Industrial Bactericide

Maximum Performance in metalworking fluid concentrates.

CONTRAM™ ST-1 is a highly concentrated industrial bactericide based on N,N Methylenebismorpholine, an extremely effective anti-bacterial compound for use in aqueous metalworking fluids. CONTRAM ST-1 provides a unique balance of oil and water solubility allowing for longer fluid stability and it is proven to be highly effective against a wide variety of bacteria.


Enhanced Performance

  • Long-lasting, persistent bacteria control for extended fluid life with minimal tankside supplements
  • Exceptional stability in metalworking fluid concentrates
  • Unique solubility properties in both oil and water
  • Safe and effective when applied and handled properly – not classified as a skin sensitizer
  • Extensive history of successful use – millions of liters of diluted metalworking fluid have been protected with CONTRAM ST-1

Typical Properties

Appearance Clear, light yellow liquid
pH, dilute 9.0-11.0
Activity, % > 98
Activity, % Oil and Water Soluble
Total Bound Formaldehyde Content, % 14-16

Biocidal Efficacy

CONTRAM ST-1 has demonstrated efficacy against a wide variety of bacteria and limited efficacy against fungi, including the following typical metalworking fluid spoilage organisms:

Acremonium spec.
Candida albicans
Escherichia coli
Fusarium spec.
Klebsiella aerogenes
Legionella pneumophila
Mycobacterium immunogenum
Pseudomonas aeruginosa
Pseudomonas fluorescens
Pseudomonas putida
Staphylococcus aureus


In metalworking fluid concentrates and emulsion systems, a balanced solubility between the oil and water phases is key to biocidal efficacy and long-term stability in use. Unlike commonly used HHT biocide, CONTRAM ST-1 and MBO are engineered to provide greater oil phase solubility, as demonstrated by a controlled solubility study in heptane. This property is one factor that makes CONTRAM technology the ideal choice for metalworking fluid protection.


Metalworking fluid concentrate compatibility is key to the performance of CONTRAM ST-1. The above study monitored simple soluble oil concentrates protected with either CONTRAM ST-1, or the commonly-used HHT molecule. Concentrates stored at elevated temperatures were checked for emulsion performance at seven day intervals. When protected with CONTRAM ST-1, no loss of emulsion quality was observed throughout the storage period. Concentrates using HHT demonstrated complete loss of emulsion quality, resulting in a product that would be unsuitable for use following extended storage.

Recommended Use Directions

CONTRAM ST-1 is primarily recommended for incorporation into metalworking fluid concentrates intended for water dilution at the final use site.

Metalworking fluid concentrates intended for 20:1 water dilution should utilize 2.0-3.0% CONTRAM ST-1 by weight. This will result in a final dilution concentration of 1,000-1,500 ppm. Treat rates in metalworking fluid concentrates intended for different water dilution rates should be adjusted to deliver 1,000-1,500 ppm CONTRAM ST-1 in the final working dilution.

In-Depth Industry Knowledge

Lubrizol’s comprehensive knowledge of the metalworking fluid industry helps us provide unequaled consultative support at all stages of the metalworking fluid application. From product development in the laboratory to troubleshooting challenges in the end use environment, we work with customers on specific formulation strategies to improve products or to help incorporate additives in existing product lines.

Assured Compliance

The active chemistry in CONTRAM ST-1 is being supported by Lubrizol under the European Biocidal Products Directive (BPD). This places Lubrizol in the best position to assist our customers in the design of their concentrate formulations in full compliance with current legislation and to assist in developing products with the most suitable labeling for the end user application. Our commitment to this program ensures the longterm availability of this performance chemistry for the metalworking fluid industry.

Health and Safety

Lubrizol supports customers through:

  • Product Safety and Compliance Department, providing expert communication and advice to help educate on product risk and proper handling
  •, providing timely notification on the challenges and mandates driving the metalworking industry
  • Commitment to the BPD, providing assurance through a comprehensive set of health and safety data for each of the active molecules in our product range.

Please note: Use biocides safely. Always read the label and product information before use.

When properly applied, these products will safely and effectively control the hazards of microbial growth in metalworking fluids.

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