Protek have developed an excellent water based stain blocking primer that offers better performance than both current water based and solvent borne products.
• Excellent tannin blocking performance
• Fast drying, can be top coated in an hour
• Can be used in low temperatures
• Cationic primer with flash rust resistance for nail heads
• Low VOC
Surface Preparation
Surfaces should be clean and dry before application.  If surfaces need to be cleaned we recommend warm water with detergent and a stiff brush. 
Application
Mix well before use. Protek Stain Blocking Primer can be applied by spray, brush or roller. Allow each coat to dry before applying the next; this should take up to 1 hour.  We recommend 2 coats especially if a white or off-white topcoat is being applied. If applying to bare untreated timber we recommend first applying a Wood Preserver before the primer. This primer will stop the tannin bleed from knots in the wood but it will not stop the resin coming through. If the timber is resinous a knotting agent should still be applied to the knots.
Use with care
• Protek Stain Blocking Primer MUST be fully dry before applying the top coat. 
• Brushes must be fully washed out before using with the top coat. 
• In their wet forms Stain Blocking Primer and other top coats are not compatible and should never be mixed.
Coverage: 1 litre will cover approximately 8m2 per coat depending on the moisture content and porosity of the surface. For best results it is recommended 2 coats are applied before the topcoat
Advice: 2-3 coats are recommended depending on wood species and surface characteristics. Please read Health & Safety guidance or product labelling for full