Pallets of red drums of HDI biuret polyisocyanate stacked in a warehouse

HDI Biuret-Based Polyisocyanates

Name: HDI Biuret-Based Polyisocyanates
Brand: KingZhi Chemistry

The HB series for flexible high build light resistant polyurethane coatings

Overview

What This Product Is and Who Buys It

The HB series is a group of aliphatic polyisocyanates based on HDI biuret, developed as curing agents for high performance light resistant polyurethane coatings. Four grades cover the range from solvent free high build work at 100 percent solids down to low viscosity formulation at 50 percent solids.

Key Benefits

Excellent UV and weather resistance
Low free HDI monomer content at 0.2 percent or below
Good flexibility and mechanical performance compared with isocyanurate hardeners
Broad compatibility with polyester and polyether polyols

Drums of HDI biuret hardener being loaded into a shipping container

Applications

Where This Material Is Used

Automotive OEM and refinish coatingsIndustrial protective coatingsMachinery and equipment finishesMetal and plastic coatingsHigh solids and low VOC PU systems

Who It Is For

High solids and low VOC coating formulators
Machinery and equipment finish producers
Metal and plastic coating manufacturers
Automotive refinish system developers

Problems It Solves

VOC limits forcing a move away from conventional solventborne systems
High build coatings cracking because the film is too rigid
Workplace exposure concerns around free isocyanate monomer

Technical

Technical Features

HB-100 solvent free at 100 percent solids for high build work
HB-75B and HB-75MX at 75 percent solids in BA and MPA/X
HB-50BM at 50 percent solids in BA/MPA for low viscosity formulation
Recommended NCO/OH ratio 0.9 to 1.1

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	Solvent	Solids (%)	NCO (%)	Viscosity (25°C, mPa·s)	Typical Use
HB-100	None	100	21.7 – 22.3	9000 ± 2000	Solvent-free, high-build PU coatings
HB-75B	BA	75	16.2 – 16.8	150 ± 50	General solventborne PU coatings
HB-75MX	MPA/X	75	16.2 – 16.8	225 ± 75	Improved flow and leveling systems
HB-50BM	BA / MPA	50	10.5 – 11.5	14 ± 10	Low-viscosity PU formulations

Grades listed are representative and not exhaustive. Ask for the batch certificate of analysis on the grade you intend to buy.

Handling

Packaging Storage and Shelf Life

Packaging: 200 kg steel drums, 1,000 kg IBC, bulk supply available on request
Storage Temperature: 5 to 30°C in original sealed containers
Protect From: Moisture and direct sunlight
Shelf Life: 12 months

Use Guide

How to Work With This Product

Work to an NCO/OH ratio between 0.9 and 1.1
Mix thoroughly before application
Confirm pot life against your formulation, temperature and humidity before scaling up
Apply by spray, roller or brush
Store in original sealed containers between 5 and 30 degrees C

Comparison

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

Industries Using This Product

Pallets of sealed steel drums of coating raw material in a warehouse

IndustryIndustrial and Protective Coatings

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

Solutions

Where This Product Fits In A Wider System

Chemical process plant columns and piping under a clear sky

SolutionTwo Component Polyurethane Coating Systems

A 2K polyurethane coating is a negotiation between pot life, dry speed, hardness and weathering. This is how we work through it with a formulator.

See The Process

FAQ

HDI Biuret Questions

Which grade is right for a high build coating?

HB-100, the solvent free grade at 21.7 to 22.3 percent NCO. Its viscosity of 9000 ± 2000 mPa·s at 25 degrees C is high, which is exactly what a high build system needs.

What is the lowest viscosity grade?

HB-50BM at 50 percent solids in BA/MPA, with a viscosity of 14 ± 10 mPa·s and 10.5 to 11.5 percent NCO.

What is the free HDI monomer content?

0.2 percent or below across the series. Ask for the batch certificate if your site has a specific exposure limit to meet.

Biuret or isocyanurate for my system?

Biuret grades give more flexibility and suit high build and solvent free work. Isocyanurate grades give higher crosslink density and faster drying. Our HDI Trimer page lists the isocyanurate grades side by side.

Which polyols are compatible?

The series shows broad compatibility with both polyester and polyether polyols, and suits solventborne and high solids systems.