Processing is particularly easy since BLUESIL PRIM PM 821 is delivered ready to use.
In all cases, it must be applied to surfaces from which the grease and dust has been removed and which are clean and dry.
BLUESIL PRIM PM 821 is applied with a brush or with a dry cloth in a thin and uniform coat.
Once BLUESIL PRIM PM 821 has been applied, it is recommended to wait for minute at room temperature, before applying the silicone elastomer on the primer-prepared surface. A maximum opened time of 6 hours should be respected.
The working temperatures of the BLUESIL PRIM PM 821 must be respected: +5 to + 30°C. The use of the primer at high temperatures will cause a very fast evaporation and thus lead to irregular layers of primers.
In order to avoid hydrolysis phenomenon, it is recommended not to leave the tin of primer in contact with atmospheric humidity but to fill only small amounts of primer into a small container.
In all cases, if a hydrolysis phenomenon appears, it is recommended to remove the primer and to re-apply it again.

BLUESIL PRIM PM 821 may be stored at temperatures between 2°C / 36°F and 30°C / 86°F for up to 12 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.


BLUESIL PRIM PM 821 is an adhesion promoter for silicones elastomers: CAF one-component and RTV-2 two-components curing at room temperature, for LSR (Liquid Silicone Rubber), as well as Heat Curing Rubbers (HCR).
BLUESIL PRIM PM 821 is used to improve silicone elastomer adhesion on various type of substrates such as:
Steels, aluminium, stainless steel, coated steels (epoxy, PES, PU paints), plastic and composite materials with glass fibre, epoxy resin.



BLUESIL PRIM PM 821 is ready-to-use.
BLUESIL PRIM PM 821 allows quick and optimal adhesion development at room temperature on various types of materials subject or not to thermal stresses.

Asia Pacific;Europe Middle East Africa;Central and South America;North America




Specific Gravity0.75Monocomp