Methylchloroisothiazolinone

AKA “5-Chloro-2-methyl-4-isothiazolin-3-one, 26172-55-4, CMIT, 5-Chloro-2-methyl-3(2H)-isothiazolone, 5-Chloro-2-methyl-3-isothiazolone, Kathon CG 5243, 3(2H)-Isothiazolone, 5-chloro-2-methyl-, 5-chloro-N-methylisothiazolone, 5-chloro-2-methylisothiazolin-3-one”

Preservative

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Ingredient Facts

Methylchloroisothiazolinone

AKA: 5-Chloro-2-methyl-4-isothiazolin-3-one, 26172-55-4, CMIT, 5-Chloro-2-methyl-3(2H)-isothiazolone, 5-Chloro-2-methyl-3-isothiazolone, Kathon CG 5243, 3(2H)-Isothiazolone, 5-chloro-2-methyl-, 5-chloro-N-methylisothiazolone, 5-chloro-2-methylisothiazolin-3-one

Preservative · Preservative · EWG: 6

Synthetic

Preservative

Medicated Active

Not Clean

5-Chloro-2-methyl-2H-isothiazol-3-one

Solubility Solubility in g/100 mL solvent: water, infinite

Formula

C4H4ClNOS

Mol. Weight

149.60

CAS #

26172-55-4

Form

Liquid

State

Liquid

See origin →

Functions

Preservative

Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.

Preserves Formula

Fights Bacteria

Prevents microbial growth

Traditional Use

Synthesized in the 1970s as a broad-spectrum biocide and preservative for cosmetics and personal care products. Created to address the need for more stable and effective antimicrobial preservatives.