Desmodur-HDI based curing agent

Covestro Desmodur® N75 BA lightfast HDI biuret curing agent Good chemical resistance and flexibility

type	Aliphatic polyisocyanate (hexamethylene diisocyanate biuret)
form of supply	About 75% butyl acetate solution
use	Curing agent components for lightfast polyurethane coatings

Specification

characteristic	Numerical value	Units of measurement	method
NCO content	16.5±0.3	%	DIN ENISO 11909
Non-volatile content (2.2g/120min/100°C)	75±1	%	DIN ENISO 3251
Viscosity, 23°C	160±50	mPa·s	DIN ENISO 3219/A.3
Color value (Hazen)	≤40		DIN EN 1557
HDI monomer	<0.5	%	DIN ENISO 10283

Other data*

characteristic	Numerical value	Units of measurement	method
Viscosity, 25°C	about 140	mPa·s	DIN ENISO 3219/A.3
equivalent	about 255
Flash point	about 35	°C	DIN 53213/1
Density@20°C	about 1.07	g/ml	DIN EN ISO 2811

*This data is general information and is not part of the product specification.

Solubility/Dilution
Desmodur® N75 BA can be used with esters, ketones, aromatic hydrocarbon solvents such as: propyl methoxyacetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, xylene, No. 100 naphtha solvent and Its mixture is diluted. Generally have good miscibility with these solvents. However, the storage stability of the resulting solutions must be tested. Polyurethane grade solvents should be used (less than 0.05% water, no reactive groups such as hydroxyl or amino groups). Butyl acetate and ethyl acetate are not recommended as single and primary diluents because low solids solutions are unstable. Aliphatic hydrocarbons are not suitable solvents. Desmodur® N75 BA should not be diluted below 40% solids. Solutions with low binder content may experience turbidity and precipitation after prolonged storage.

compatibility
Desmodur® N75 BA can generally be used with the following products. Namely: Desmodur® N3200, N3300, N3400, N3600 and Desmodur® Z4470 aliphatic polyisocyanates;

Desmodur® Aromatic polyisocyanates L, HL and IL; Desmophen® 651 and 670 polyester polyols; Desmophen® A polyacrylates; Desmophen® 1380BT polyether polyols. However, the compatibility of the prepared solution must be tested.

Features/Applications
Desmodur® N75 BA is mainly used as the curing agent component of lightfast two-component polyurethane coatings with good chemical resistance, weather resistance, excellent gloss retention and excellent mechanical properties. Desirable co-reactants are polyacrylates or polyester polyols. Coating systems formulated with Desmodur® N75 are self-drying and drying for use in automotive and industrial finishes such as wood, furniture, plastic finishing and corrosion protection.

store
Desmodur® N75 is moisture sensitive and should be stored in its original sealed container. When properly stored at room temperature, this product has a shelf life of at least 6 months.

Safety: Hazard Identification
Flammable. Skin contact may cause allergic reactions. Repeated exposure to this product can cause dry, cracked skin. Product vapors can cause drowsiness and dizziness. Contains isocyanates. Product Safety Data Sheets must be strictly followed, which include information on labelling, transportation and storage, as well as information on product use, product safety and ecology.