Overview

Dowsil 799 Plastic and Glass Silicone Sealant is a one-part, low modulus, neutral curing silicone sealant designed for glazing and weather-sealing of windows. This silicone sealant is easy to apply and offers durable adhesion to most porous and non-porous substrates including masonry, brick, aluminium, PVC, glass and glazed surfaces with high elasticity. Its formula contains fungicide making it mold and mildew resistant, it also resists ultra-violet radiation and is non-corrosive to metals.

• Ideal for glazing and weather-sealing of windows
• Low odour
• Excellent weather resistance
• Mould and mildew resistant
• Non-corrosive to metals
• Good unprimed adhesion to a variety of substrates
• Confirms to ISO11600-F&G25LM

Preparation

Ensure that surfaces to be sealed are clean, dry, sound and free from frost.

• Non-porous surfaces, such as aluminium, glass etc., should be cleaned with a suitable solvent for the substrate.
• Porous substrates such as concrete, brickwork, mortar, etc. must be mechanically cleaned from loose particles using a steel brush, sanding disc, or any similar means.
• The use of a primer is recommended to obtain durable adhesion performance on such porous substrates, or if water immersion is expected to occur during the service life of the assembly. Otherwise, primers are not usually required but might be needed for some specific substrates to achieve optimum adhesion.
• Areas adjacent to the joints should be masked with tape to prevent contamination of the substrates and to ensure a neat sealant line. Masking tape should be removed immediately after tooling.
• When back-up material is required, a closed cell polyethylene backer rod is recommended. Low tack polyethylene tape should be used in joints too shallow to allow the use of a backer rod. Back-up materials provide back pressure and prevent three sided adhesion that limits sealant movement capability.

Application

If possible test on a small area before you start to ensure compatibility. Ensure that surfaces to be sealed are clean, dry, sound and free from frost, release agents, old sealants and other contaminants which could impair adhesion.

• The silicone sealant is ready for immediate use. Cut the tip off the cartridge and screw on the nozzle and cut the nozzle to the desired bead size. We recommend using the Geocel Cox Skeleton Gun for application.
• The joint should be tooled within 5-10 minutes of application to ensure good contact between the sealant and the substrate. Tooling of the sealant also gives a smooth, professional finish for best results use Bedec Silicone Profilers.

Always follow manufacturer's instructions found on the packaging

Aftercare & Storage