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SynChem – Resins & Varnishes

Synthite AC-41 Polyurethane varnish

Synthite AC-41 is an air drying finishing varnishes based on polyurethane.


Synthite AC-41 has the following excellent properties:

  • fast drying - units can be handled in 30 min.
  • easy application (dipping, brushing, spraying)
  • hohe Temperaturbeständigkeit
  • superior abrasion resistance
  • excellent adhesion to most surfaces
  • transformer oil resistance ASTM D 155-55
  • corrosion and humidity resistance

Electrical engineering and electronic devices.


Class H (180 °C) acc. UL 1446, MW 35-C, Twisted Pairs.

Delivery forms

4.5 kg, 22.5 kg and spray bottles on request.






Store in cool dry place (max. 30 °C) away from direct sunlight. Protect from moisture and humidity. Shelf life is 36 months when stored in closed original container at max. 30 °C.


Curing is possible in explosion protected environments under a fume hood at ambient conditions:
Air drying times at 25 °C:

  • 10 min. dust-dry
  • 1 h touch-proof
  • 48 h cured

Cured Synthite AC-41 is biologically inactive and safe to health. Always refer to the safety data sheet and implement common protective measures when processing the varnish.


Clean tools with thinner T 200 in time. Maintenance and care of coating equipment, especially cleaning, must be carried out according to operational requirements. Always refer to the user manual of the equipment. 


When spray-coating with thinner T 200, Synthite AC-41 is adapted to processing viscosities in common manual spraying nozzles. Usually you 20-25 % thinner. It is possible to adjust the viscosity with T200 for dip coating. Before longer air contact, ensure that the dipping bath surface does not become dry by placing a nitrogen blanket. Synthite AC-41 is supplied ready-to-use for brushing application. Recommended coating thickness: less than 30-40 µm.

Always observe the specifications on the safety data sheet and relevant safety organisation regulations. 

Technical data
Coating thickness 
Unit of measure Conditions  Value  Test method 
µm    60-75 ASTM D-115
Resistance  Resistance  Resistance  Resistance 
Conditions  Blistering  Rusting  Cracking  Test method 
Water no no no  
10 % sulfuric acid no no no ISO 4628/2-3-4
1% Natrium hydroxide no no no ISO 4628/2-3-4
saltwater no no no ISO 4628/2-3-4
Liquid phase
Dilution  Specific density  Viscosity  Viscosity 
Unit of measure Bedingung  Werte  Prüfmethode 
g/l  25 °C 900±20  
25 °C 50-65 Ford Cup 4
25 °C 40-60 ISO Cup 6
Dielectric strength  Dielectric strength 
Unit of measure Conditions  Value  Test method 
kV/mm  dry / 0.025 mm film thickness 80 ASTM D-115
kV/mm  after 24 h water immersion / 0.025 film thickness 48