FAQs
What does DOWSIL PR-1200 do?
PR-1200 is an adhesion-promoting primer that improves the bond between room-temperature and heat-curing silicones and surfaces such as glass, plastics, metals, ceramics, and masonry. Based on silane coupling agents, it prepares difficult surfaces so silicone sealants and coatings adhere more reliably in demanding assembly and construction applications.
How should PR-1200 be applied?
Apply it in a very light, even coat by wiping, dipping, or spraying, and wipe off excess to avoid overapplication, which can leave a white, chalky surface. For dip or spray coating, diluting two to four times with solvent helps avoid build-up. Clean and degrease the surface first, then let the solvents evaporate.
Why is the primer available in red and clear?
The two versions share the same adhesion-promoting chemistry and differ in color. The red tint makes it easy to see where primer has been applied and confirm complete coverage, while the clear version is chosen when no visible tint on the finished surface is acceptable or preferred.
How should PR-1200 be stored?
Because it is moisture-sensitive, keep containers tightly closed with minimal headspace and store below 32°C. Do not use material that has turned milky or shows a large amount of white precipitate, as that indicates moisture contamination. Pour small amounts for immediate use into clean, dry containers and discard leftovers.
Do I still need to clean the surface if I use a primer?
Yes. Priming complements cleaning rather than replacing it. Surfaces should be cleaned and degreased with a suitable solvent, allowing the solvent to fully evaporate before the primer is applied. Good cleaning increases surface area for bonding, and for hard-to-bond surfaces, additional surface activation may further improve adhesion.
