Octylisothiazolinone, commonly abbreviated as OIT, is an isothiazolinone-based antimicrobial compound. It is also known as Octhilinone and 2-n-Octyl-4-isothiazolin-3-one. The substance is primarily recognized for antimicrobial and antifungal activity and has been used extensively in preservation systems for formulated products.
OIT is particularly associated with industrial and specialty applications such as coatings, paints, adhesives, sealants and treated materials. Its use in a cosmetic formulation requires separate evaluation because an antimicrobial substance used in industrial or biocidal applications is not automatically authorized as a cosmetic preservative. European regulatory information specifically identifies OIT, CAS 26530-20-1, in relation to biocidal and environmental applications.
Octylisothiazolinone has CAS Number 26530-20-1 and EC Number 247-761-7. Its molecular formula is C₁₁H₁₉NOS, and its molecular weight is 213.34 g/mol. The substance is also described as 2-Octyl-4-isothiazolin-3-one or 2-Octyl-1,2-thiazol-3-one.
OIT has a relatively low melting point compared with many crystalline raw materials. TCI reports a reference melting point of approximately 23°C, meaning the material can change physical state close to normal room temperature depending on storage conditions. TCI describes its research-grade material as having a minimum purity of 98.0% by GC.
The physical appearance can therefore vary with temperature and material handling. TCI's specification describes the material as ranging from white or colorless to yellow, and from powder or lumps to a clear liquid.
Octylisothiazolinone provides antimicrobial functionality, particularly against microorganisms responsible for deterioration of formulated products. Its activity has made it useful in preservation technologies and specialty antimicrobial applications.
The isothiazolinone structure is important to its biological activity, while the octyl substituent influences its physicochemical properties. For formulation development, OIT should be evaluated in relation to the complete preservation system, formulation composition, compatibility, concentration and intended application.
OIT also has important safety considerations. TCI's current hazard information identifies, among other classifications, skin sensitisation and significant aquatic toxicity hazards. Appropriate handling, storage and environmental controls are therefore important when working with concentrated OIT.
Octylisothiazolinone has been used in paints, coatings, adhesives, sealants, inks, construction-related formulations and treated materials where protection against microbial or fungal deterioration is required.
In the European regulatory framework, OIT has been addressed as an active substance for certain biocidal applications. For example, EU Regulation 2017/1277 identifies 2-octyl-isothiazol-3(2H)-one, CAS 26530-20-1, as an active substance for Biocidal Product Type 8, which concerns wood preservatives.
This regulatory status should not be confused with authorization as a cosmetic preservative. Cosmetic ingredients must satisfy the specific requirements applicable to cosmetic products in the destination market.
When evaluating Octylisothiazolinone for a formulation, the actual grade, purity, physical state, analytical method, compatibility and intended application should be established from the product's technical documentation.
The ≥98.0% GC purity reported by TCI is a reference specification for its own research-grade material and should not automatically be entered as the SDP commercial specification. Likewise, the approximately 23°C melting point is a reference property rather than a universal release specification.
Because OIT has sensitisation and environmental hazard classifications, formulation developers should conduct the appropriate safety and regulatory assessment before selecting it for a finished product. The concentration of the raw material should also never be confused with a permitted finished-product concentration.
As an Octylisothiazolinone Cosmetic Ingredient Manufacturer in India, Swapnroop can position OIT as a specialty antimicrobial raw material for B2B technical requirements, subject to the actual commercial grade and applicable regulatory requirements.
Customers searching for an Octylisothiazolinone supplier in India should review the CAS identity, purity, analytical method, physical characteristics, safety documentation and intended application before selecting a material. For bulk cosmetic ingredient supply, the selected grade should correspond to the customer's formulation requirements and destination-market regulations.
| Parameter | Specification |
|---|---|
| Appearance | White or colourless crystals / white powder |