Trimethylhexamethylene Diisocyanate

INCI: TRIMETHYLHEXAMETHYLENE DIISOCYANATE (MIXTURE OF 2,2,4- AND 2,4,4- ISOMERS)

CAS Number
28679-16-5
Function
Monomer/crosslinker in polyurethane synthesis — not a direct cosmetic ingredient
Safety Rating
POOR

Regulatory Status

🇪🇺 EU Status prohibited
🇺🇸 US Status permitted
US Notes Not approved as a direct cosmetic ingredient; residual free isocyanate in polymer-based products must be below detection limits

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
not established
Dermal Absorption
high
Sensitization
high

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

CRITICAL: Toxic if swallowed, inhaled, or skin-absorbed; GHS Signal Word: DANGER; UN2328; may only exist as fully reacted polyurethane backbone — never as free monomer

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Concern Level: High

Frequently Asked Questions

Is Trimethylhexamethylene Diisocyanate safe in cosmetics?

CRITICAL: Toxic if swallowed, inhaled, or skin-absorbed; GHS Signal Word: DANGER; UN2328; may only exist as fully reacted polyurethane backbone — never as free monomer The EU classifies Trimethylhexamethylene Diisocyanate as "prohibited". Safety rating: POOR.

Is Trimethylhexamethylene Diisocyanate allowed in the EU?

Trimethylhexamethylene Diisocyanate EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.

What does Trimethylhexamethylene Diisocyanate do in cosmetics?

Trimethylhexamethylene Diisocyanate functions as: Monomer/crosslinker in polyurethane synthesis — not a direct cosmetic ingredient. It is classified as a cosmetic ingredient in our database. CAS number: 28679-16-5.

What is the Margin of Safety for Trimethylhexamethylene Diisocyanate?

not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.

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