SynChem – Resins & Varnishes AQUA-THERM BC-367/832-D

AQUA-THERM BC-367/832-D is a white, 1K, water-borne varnish based on polyester.

AQUA-THERM BC-367/832-D is characterised by the following properties:

  • UL-approved
  • good moisture resistance
  • good adhesion and flexibility
  • good stability into the dipping tank (at T ˃ +5 °C)
  • relatively high curing cycle at low temperatures (110-130 °C)
  • high flash point (over 95 °C)
  • suitable for the impregnation of motors working in humid environments
Download datasheet


AQUA-THERM BC-367/832-D is a proven dip varnish for impregnating:

  • motors in humid environments
  • small- and medium-size stators
  • small transformers
  • coils


  • UL-approved Class 180, File E 317427
  • OBOR2.E317427, OBJS2.E317429
  • RoHS-compliant acc. 2011/65/EU
  • Temp. class acc. UL 1446
Magnet wire Twisted Pairs
MW 35-C 180 °C

Delivery forms

Aqua-Therm BC-367/832-D is supplied in 25 kg disposable containers and in 230 kg barrels.


AQUA-THERM BC-367/832-D can be stored for 12 months at room temperature in a sealed container (max. 30 °C). The impregnating resin must be protected against direct sunlight and sources of heat.

Being a water-thinnable emulsion with a very low cosolvent content, this product suffers from cold and must be stored at temperatures included between +5 and +30 °C. The stability of the product into the tank can be indedinitely extended by means of monthly addition of fresh varnish in a proportion of at least 15-20 % on the tank content. It is recommended to keep ht pH value not below 6.7.

The impregnating bath must be stirred on working days for 30 min.


Curing is possible in a closed oven with or without preheating.

Typical curing times:

at 150 °C - 2-4 h
at 130 °C - 3-5 h
at 110 °C - 5-8 h

The curing time commences once the object temperature has been reached.


Use in well ventilated area, avoid contact with skin and eyes and wear protective clothes. For more details see the technical data sheet.


Exemplary dipping process:

  1. Dilute Aqua-Therm BC-367/832-D to the desired viscosity, thinning it with drinkable water. The recommended dilution is Aqua-Therm BC-367/832-D 100 p.b.w + tap water 30-40 p.b.w.
  2. Dip the units into the varnish for 5 min. about.
  3. Let it drain for 30 min.
  4. Bake in the oven according to one of the following cycles:
    110 °C - 5-8 h
    130 °C - 3-5 h
    150 °C - 2-4 h

(Times must be taken when unit reaches the baking temperature)

Technical data

Property Conditions Values Test method
Bond strength 25 °C >180 N IEC 61033
Bond strength 155 °C >50 N IEC 61033
Property Values Test method
Thermal class H (180 °C) MW 35-C
Property Unit of measure Conditions Values Test method
Dielectric strength kV/mm 0.025 mm film 80 ASTM D-115
Liquid phase
Property Unit of measure Conditions Values Test method
Colour transparent
Specific density g/l 1020 ± 30 at 25 °C
Viscosity s at 25 °C 12-16 Ford Cup 4
Viscosity s at 25 °C 20-40 ISO Cup 3
Flashpoint °C > 95 Seta Closed Cup
pH-value 7.2 - 8.2