HDI Trimer Polyisocyanate Curing Agents
Biuret and isocyanurate grades for light stable 2K polyurethane coatings
What This Product Is and Who Buys It
This range covers aliphatic HDI based polyisocyanates in both biuret and isocyanurate form, designed as curing agents for high performance light stable polyurethane coatings. Ten grades are listed with NCO content, viscosity and colour, so a hardener can be matched to an existing formulation rather than trialled blind.
Key Benefits
- Excellent UV resistance and weather durability across the range
- Solvent free grades from 11.0 to 23.5 percent NCO for high solids work
- Solution grades at 75 and 90 percent solids where flow and levelling matter
- N 3900 is suitable for waterborne 2K polyurethane systems
Where This Material Is Used
Who It Is For
- Automotive refinish coating producers
- Industrial and protective coating formulators
- Wood and furniture finish manufacturers
- Waterborne 2K system developers
Problems It Solves
- Exterior topcoats that chalk or amber within the warranty period
- High solids formulations needing low viscosity without losing crosslink density
- Fast drying lines where the hardener sets the cycle time
Technical Features
- Biuret grades N 100, N 75 MPA/X and N 75 BA
- Isocyanurate grades N 3300, N 3390 BA/SN, N 3600, N 3790 BA, N 3800 and N 3900
- Recommended NCO/OH ratio 0.9 to 1.2 depending on formulation
- Application by spray, roller or brush
Specifications
These figures are the manufacturer grade data as published for this product family. Anything not listed below has not been confirmed and is marked TBC on request rather than estimated.
| Product | Chemical Structure | Solvent | NCO Content (%) | Viscosity (mPa·s, 25°C) | Color (APHA) | Typical Application |
|---|---|---|---|---|---|---|
| N 100 | Biuret | Solvent-free | 22.0 | 191 | ≤10000 | General-purpose light-stable PU coatings |
| N 75 MPA/X | Biuret | 75% in MPA/X (1:1) | 16.5 | 255 | ≤250 | Solventborne PU coatings |
| N 75 BA | Biuret | 75% in BA | 16.5 | 255 | ≤160 | PU coatings with improved flow and leveling |
| Product | Chemical Structure | Solvent | NCO Content (%) | Viscosity (mPa·s, 25°C) | Color (APHA) | Typical Application |
|---|---|---|---|---|---|---|
| N 3300 | Isocyanurate | Solvent-free | 21.8 | 193 | ≤3000 | Standard-grade PU curing agent |
| N 3390 BA/SN | Isocyanurate | 90% in BA/SN (1:1) | 19.6 | 214 | ≤550 | Standard solventborne PU systems |
| N 3600 | Isocyanurate | Solvent-free | 23.0 | 183 | ≤1200 | Low-viscosity PU curing agent |
| N 3790 BA | Isocyanurate | 90% in BA | 17.8 | 236 | ≤1800 | Fast-drying PU coatings |
| N 3800 | Isocyanurate | Solvent-free | 11.0 | 382 | ≤6000 | Flexible PU coatings |
| N 3900 | Isocyanurate | Solvent-free | 23.5 | 179 | ≤730 | Weather-resistant coatings, suitable for waterborne 2K PU |
Grades listed are representative and not exhaustive. Ask for the batch certificate of analysis on the grade you intend to buy.
Packaging Storage and Shelf Life
- Packaging
- 200 kg steel drums, 1,000 kg IBC, bulk tank truck supply available on request
- Storage Temperature
- 5 to 30°C in original sealed containers
- Protect From
- Moisture, heat and direct sunlight
- Shelf Life
- 12 months under recommended storage conditions
How to Work With This Product
- Confirm the NCO/OH ratio against your polyol, usually between 0.9 and 1.2
- Mix thoroughly before application; incomplete mixing shows up as soft spots
- Establish pot life on your own line, since it depends on polyol type, catalyst, temperature and humidity
- Apply by spray, roller or brush according to the viscosity of the selected grade
- Reseal partly used drums immediately, because moisture ingress consumes NCO
How It Compares
Within the Curing Agent category this product is positioned by the numbers in the table above rather than by a marketing claim. Compare NCO content, viscosity, equivalent weight or hydroxyl value against the alternative you are considering, and if the two are close, ask us for both samples and decide on your own line.
Quality and Documentation
Quality control runs across incoming raw materials, production and finished product inspection. A batch certificate of analysis is supplied with every shipment. We are a supply and trading company working with named manufacturers and OEM partners, so certification held by the producing plant is provided on request per grade rather than claimed here as ours.
Customisation
Customised grades and packing formats are available through our OEM partners and specialised manufacturing facilities. Tell us the property you need to move and we will say whether it is a grade change, a packaging change or not possible.
Industries Using This Product
Automotive coatings and interiors are where yellowing resistance, gloss retention and seat comfort are all judged by the end customer rather than by a laboratory.
See Applications
Protective coatings are bought on service life. The raw material decisions behind them are about crosslink density, film flexibility and how the system behaves once VOC limits tighten.
See Applications
Comfort products are judged by how they feel after three years, not on the day they ship. That is a raw material question about foam resilience and coating durability.
See Applications
HDI Trimer Questions
Which grade should I start with?
N 3300 at 21.8 percent NCO solvent free is the standard general purpose isocyanurate curing agent. If you need lower viscosity at high solids, look at N 3600 at 23.0 percent NCO and 183 mPa·s.
Do you have a grade for waterborne systems?
N 3900 at 23.5 percent NCO is listed as suitable for waterborne 2K polyurethane as well as weather resistant coatings.
What is the difference between the N 100 and N 3300 grades?
N 100 is a biuret at 22.0 percent NCO and 191 mPa·s; N 3300 is an isocyanurate at 21.8 percent NCO and 193 mPa·s. The isocyanurate gives higher crosslink density and better weathering, the biuret more flexibility.
What is the shelf life?
12 months in original sealed containers stored between 5 and 30 degrees C, protected from moisture, heat and direct sunlight.
Can you supply in bulk?
Yes. 200 kg steel drums and 1,000 kg IBC are standard, and bulk tank truck supply is available on request for regular volumes.
Products Often Bought Alongside This One
The HB series for flexible high build light resistant polyurethane coatings
View Specifications
Light resistant isocyanurate hardeners for high end decorative coatings
View Specifications
The aliphatic building block behind non yellowing polyurethane coatings
View Specifications
Fast curing aromatic hardeners for 2K polyurethane coatings and adhesives
View SpecificationsRequest a Quote or a Sample of HDI Trimer
Samples take about 7 days and are free of charge with shipping at your cost. Production orders ship 20-30 days after the deposit is received.