What is isothiazolinone

Isothiazolinone is a widely used preservative and fungicide with efficient and broad-spectrum bactericidal properties. It is usually composed of two compounds: 5-chloro-2-methyl-4-isothiazoline-3-one (CMI) and 2-methyl-4-isothiazoline-3-one (MI), and these two compounds are often mixed in a 3:1 ratio, which is often referred to as "cassonne". Isothiazolinone exhibits high bactericidal activity against both Gram positive and negative bacteria, and has a good inhibitory effect on streptococcus and yeast. It is widely used for sterilization and anti-corrosion in industries such as cosmetics, personal care products, coatings, water-based polymers, metal cutting fluids, adhesives, inks, dyes, paraffin liquids, wood, leather making, water treatment, industrial circulating water, swimming pool water treatment, pulp and paper making, etc.
In addition, isothiazolinone also has good miscibility, can be mixed with chlorine and most anionic, cationic, and non-ionic surfactants, and has the characteristics of no residue, safe operation, good compatibility, strong stability, and low usage cost.
In the cosmetics industry, isothiazolinone is used due to its low toxicity, wide range of antibacterial effects, strong efficacy, and good compatibility with cosmetic raw materials, and can be directly added to cosmetics. However, in recent years, due to concerns about its potential allergic reactions, some regions have restricted or prohibited its use in certain types of cosmetics.
In industrial applications, isothiazolinone as a water treatment agent has good miscibility and can effectively control microbial growth, preventing water quality deterioration.
It should be noted that isothiazolinone is corrosive and irritating to the skin and eyes, therefore appropriate safety precautions should be taken during operation.

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