Which materials can cause discolouration of a sealant?

Certain materials are known to release migrating substances that can affect the colour of sealant, including:

• rubber and rubber-like materials such as EPDM or neoprene
• bituminous products
• coatings, paints or varnishes containing wax components
• adhesives or adhesive residues

These situations often occur on substrates such as uPVC, stainless steel, polycarbonate, polyacrylate or coated metal provided with a protective film.