异噻唑啉酮

Description

Methylchloroisothiazolinone is identified by CAS 26172-55-4, molecular formula C4H4ClNOS and molecular weight 148.97 g/mol. UNII DEL7T5QRPN; ChEBI 53621; InChIKey DHNRXBZYEKSXIM-UHFFFAOYSA-N. Melting Point: 54-55 °C; Solubility: In water, 706-751 g/L at 20 °C; Vapor Pressure: 0.018 mm Hg at 25 °C.

Identification

CAS Registry Number	26172-55-4
PubChem CID	33344
Molecular formula	C4H4ClNOS
Molecular weight	148.97 g/mol
IUPAC name	5-chloro-2-methyl-1,2-thiazol-3-one
InChIKey	DHNRXBZYEKSXIM-UHFFFAOYSA-N
UNII (FDA)	DEL7T5QRPN
ChEBI ID	CHEBI:53621

Computed Descriptors

Molecular Weight	149.60
XLogP3	0.9
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	2
Rotatable Bond Count	0
Exact Mass	148.9702126
Monoisotopic Mass	148.9702126
Topological Polar Surface Area	45.6
Heavy Atom Count	8
Formal Charge	0

Physical & Chemical Properties

Melting Point	54-55 °C
Solubility	In water, 706-751 g/L at 20 °C
Vapor Pressure	0.018 mm Hg at 25 °C
LogP	log Kow = 0.401 at 24 °C

Physical description & handling notes

• Liquid
• Crystals from ligroin (60-90 °C)
• Solubility in g/100 mL solvent: water, infinite
• Solubility in g/100 mL solvent: ethyl acetate, 4.31; methanol, 4.40, toluene, 4.07; hexane, 0.28
• In ethyl acetate, 38.06 g/L at 10 °C
• For a mixture of 5-chloro-2-methyl-3(2H)-isothiazolone and 2-methyl-3(2H)-isothiazolone: Clear light amber liquid; density: 1.256 - 1.296 g/mL at 20-25 °C; viscosity: 11.4 cP at 25.7 °C

Regulatory Status

Regulatory & Food Contact	FDA Cumulative Estimated Daily Intake (CEDI): FCS FDA Inventory of Food Contact Substances Listed in 21 CFR: FCS CIR / INCI: Cosmetic ingredients (Methylchloroisothiazolinone) -> CIR (Cosmetic Ingredient Review) CIR / INCI: Preservative
GHS notification summary	1.3% (31 / 2393)

GHS Hazard Classification

GHS notification summary	1.3% (31 / 2393)
Reported hazard statements	H300 (20.2%), H301, H311 (24%), H310 (31.2%), H314 (98.3%), H317 (98.4%), H318 (64.9%), H330 (38.7%)

Documented Uses

• CIR ingredient: Methylchloroisothiazolinone
• Kathon preparations are used as preservatives in cosmetics and in many industrial applications: metalworking fluids, latex paints, adhesives, glues, developing solutions, and slime control agents in paper mills. [Marks, p. 102-4] Used as a preservative in leather processing; [PMID 21938525] Exposed workers include house painters, printers, housekeepers, and machinists.
• Metal Machining [Category: Heat or Machine]
• Semiconductor Manufacturing [Category: Industry]
• Pulp and Paper Processing [Category: Industry]
• Painting (Pigments, Binders, and Biocides) [Category: Paint]

Synonyms

5-Chloro-2-methyl-4-isothiazolin-3-one; 26172-55-4; Methylchloroisothiazolinone; 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; 5-chloro-n-methylisothiazolin-3-one; HS 818; n-methyl-5-chloroisothiazolone; DEL7T5QRPN; DTXSID9034286; 4-ISOTHIAZOLIN-3-ONE, 5-CHLORO-2-METHYL-

Frequently Asked Questions

What are the CAS number and molecular formula of Methylchloroisothiazolinone?

CAS 26172-55-4; molecular formula C4H4ClNOS; molecular weight 148.97 g/mol.

What other names is Methylchloroisothiazolinone known by?

5-Chloro-2-methyl-4-isothiazolin-3-one, 26172-55-4, Methylchloroisothiazolinone, CMIT, 5-Chloro-2-methyl-3(2H)-isothiazolone, 5-Chloro-2-methyl-3-isothiazolone.

What is the regulatory status of Methylchloroisothiazolinone?

Documented regulatory listings: FDA Cumulative Estimated Daily Intake (CEDI): FCS; FDA Inventory of Food Contact Substances Listed in 21 CFR: FCS; CIR / INCI: Cosmetic ingredients (Methylchloroisothiazolinone) -> CIR (Cosmetic Ingredient Review).

Is Methylchloroisothiazolinone classified as hazardous?

1.3% of GHS notifications report no hazard classification (31 of 2393).

What are the key physical properties of Methylchloroisothiazolinone?

Melting Point: 54-55 °C; Solubility: In water, 706-751 g/L at 20 °C; Vapor Pressure: 0.018 mm Hg at 25 °C; LogP: log Kow = 0.401 at 24 °C.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.