N40 PRIMER

Bostik N40 Primer is a clear, non-staining, solvent-based primer and cleaner in one, built to promote adhesion of polyurethane sealants and waterproof membrane systems to non-porous substrates. It's a one-part system, so there's no mixing required, and it dries in just 5 to 10 minutes so sealant application can follow shortly after.
It's purpose-matched to Bostik's own polyurethane sealant range, including Seal 'N' Flex FC, Matrix FC, and Fireban One, giving installers a reliable prep step before sealing metal and rigid plastic joints. Cleaning and priming happens in the one action, cutting a step out of surface preparation.

Why choose N40 Primer?
N40 Primer is a solvent-based formula that dries fast, and cleans as it primes in a single wipe. Sealant should be installed within 4 hours of priming, otherwise the surface needs re-priming, so timing on site stays straightforward. It's non-staining and formulated to leave surfaces clear, ready for a clean bond.

Where to use it
N40 Primer is designed for non-porous substrates including brass, bronze, copper, mill finished and anodised aluminium, bright and galvanised steel, stainless steel, ABS and uPVC rigid plastics, gel-coated fibreglass, porcelain, and glazed ceramic tiles. Apply using the two-cloth method: dampen a clean cloth with primer and rub over the surface, then immediately buff off residue with a second clean, dry cloth. Allow at least 5 minutes drying time before installing backing rods or sealant.

TIP: Working on concrete, brick, blockwork, or other porous substrates instead? Try Bostik N49 Primer.