On account of its low water solubility, Exolit AP 423 is particularly suitable as an ”acid donor” for intumescent coatings. Other essential components of intumescent systems include a binder, a carbon donor (e.g. pentaerythritol) and a blowing agent (e.g. melamine).
On exposure to flame, intumescent coatings form a carbonaceous foam which effectively shields the underlying material from temperature increases.
Steel structures coated with intumescent paints can meet the requirements of fire resistance classes specified in DIN, BS or ASTM.
The application of Exolit AP 423 based intumescent coatings on wood or plastics enables these materials to qualify for Building Material Class B (DIN EN 13501-1).
Exolit AP 423 imparts a good flame-retardant effect to adhesives and sealants when it is incorporated into the base formulation at the rate of 10 - 20 %.