Covestro Desmodur N3375 BA/SN HDI trimer curing agent for light-resistant polyurethane coatings

Type Aliphatic polyisocyanate (HDI trimer )
Form of Supply About 75% butyl acetate/solvent naphtha No. 100 (1:1) solution
Application           Used as a curing agent component for light-resistant polyurethane coatings

Characteristics             Value               Unit             Test Method

NCO Content
Content of non-volatile components
Viscosity, 23°C         85 ± 15         mPa·s           M068-DIN 53019
Color Value (Hazen)
HDI Monomer               ≤ 0.15           %
Other data*
Characteristics             Value               Unit               Test Method

Viscosity, 25°C         approx. 75           mPa·s             DIN EN ISO 3219/A.3
Equivalent about 258
Flash point               approx. 46
Density at 20 °C       approx. 1.08           g/ml               DIN EN ISO 2811
*This data is general information and is not part of the product specification.

Desmodur® N3375 BA/SN can be used with esters, ketones, and aromatic solvents such as: ethyl acetate, butyl acetate, methoxypropyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, Dilute with xylene, No. 100 naphtha solvent and their mixture. Generally have good miscibility with these solvents. However, the storage stability of the prepared solution must be tested. Polyurethane grade solvents should be used (less than 0.05% water, no reactive groups such as hydroxyl or amino groups). Aliphatic hydrocarbons are not suitable as solvents. Desmodur® N 3375 BA/SN should not be diluted below 40% solids. Solutions with low binder content may develop turbidity and precipitation after long-term storage.

Desmodur® N3375 BA/SN can generally be used with the following products. Namely: Desmodur® N100, N75, N3200, N3400, N3600 and Desmodur® Z4470 type aliphatic polyisocyanate; Desmodur® L, HL and IL type aromatic polyisocyanate; Desmophen® 670 type polyester polyol; Desmophen® A type polyisocyanate Acrylate. However, the compatibility of the prepared solutions must be tested. Desmodur® N3375 BA/SN with support��Polyester polyols such as Desmophen® 651 or polyether polyols such as Desmophen® 1380 BT are incompatible.

Desmodur® N3375 BA/SN is mainly used as a curing agent component of lightfast two-component polyurethane coatings, which have excellent chemical and weather resistance, outstanding gloss retention and excellent mechanical properties. Ideal co-reactants are polyacrylate or polyester polyols. Coating systems formulated with Desmodur® N3375 BA/SN are suitable for self-drying or baking and are mainly used for the finishing of automotive original equipment (OEM), car refinishing, transportation vehicles, industrial products and plastics.

– Store in original Covestro airtight containers.
– Recommended storage temperature: 0-30°C.
– Protect from moisture, heat and foreign substances.
General information: This product is sensitive to moisture, storage at high temperature will cause the product to darken in color and increase in viscosity.

Shelf Life
The product complies with the specifications stated in the above “Specifications or Characteristic Values” within 9 months from the date of shipment stated on the transport document, provided that the product has been stored in full compliance with the requirements of the above “Storage” clause and has been properly handled or characteristic values ​​(as applicable). If the product exceeds the above-mentioned 9-month period, it does not mean that it no longer meets the set values ​​in the specifications or characteristic values. However, it is recommended that products older than 9 months from the date of shipment be tested before use to confirm that they still comply with the values ​​set forth in the specification or characteristic values. The manufacturer does not make any promises for products that have been shipped for more than 9 months from the date of shipment, and does not accept any responsibility and liability for non-conformity to specifications or set values ​​​​in the characteristic values.