- ▸ Hardener component in high-solids, low-VOC two-component polyurethane coatings
- ▸ Automotive refinish and OEM clearcoats requiring gloss and UV color stability
- ▸ Industrial-maintenance and protective topcoats with abrasion and chemical resistance
- ▸ Wood and plastic coatings where low application viscosity is needed
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
Request SDS →Allophanate chemistry trades some of the functionality of a standard HDI isocyanurate trimer for markedly lower viscosity, which lets formulators build high-solids, low-VOC 2K-PU coatings without heavy solvent loading. Crosslinked against polyol resins, it forms weatherable films with strong abrasion, chemical, and gloss retention, the reason aliphatic HDI hardeners dominate automotive refinish and industrial-maintenance topcoats. Typical NCO content and viscosity sit below those of conventional trimer grades; the practical trade-off is a slightly lower crosslink density per equivalent, balanced by far easier application at high solids. Like every isocyanate hardener it is moisture-sensitive and liberates HDI vapor when heated or sprayed, so engineering controls and respiratory protection govern its handling
Frequently Asked Questions
Is this low-viscosity HDI allophanate-modified polyisocyanate an equivalent to Desmodur N3900?
This low-viscosity HDI allophanate-modified polyisocyanate is the generic equivalent of the grade sold as Desmodur N3900. RawSource supplies an independent equivalent — verified to your specification and Certificate of Analysis — and is not affiliated with, authorized by, or endorsed by Covestro.
