Overview

Dowsil 786 Silicone Sealant is a high-quality, one-part silicone rubber sealant offering fast curing and maximum flexibility. Designed for the sealing of refrigeration units and areas prone to food contact, Dowsil 786 provides strong adhesion to a variety of surfaces, including porcelain, cultured marble, painted surfaces, and glass, without the need for a primer. Formulated to be highly resistant to mildew and mould growth, it is perfect for use in kitchens and food preparation areas, making it a reliable choice for maintaining a safe, hygienic, and professional environment. Dowsil 786 can also be used for sealing around sinks, showers, tubs and more.

• Mould & mildew resistant
• Safe to use kitchens and food preparation areas
• Resists staining, spotting and colour changes
• Complies with FDA Regulation No. 21 CFR 177.2600
• Flexible finish - High elasticity
• Fast cure

Preparation

To ensure optimal adhesion and performance of DOWSIL™ 786 Silicone Sealant, it is important to properly prepare the surfaces before application. Follow these steps for surface preparation:

• Ensure that all surfaces to be sealed are clean, dry, and free from dust, grease, oil, moisture, frost, old sealants, or any other contaminants that could impair adhesion.
• For non-porous surfaces, clean and degrease by wiping with a suitable solvent like DOWSIL™ R-40 Universal Cleaner on a clean, lint-free cloth.
• Make sure to thoroughly dry the surface before proceeding with the sealant application.
• For porous substrates, such as concrete, brick, or mortar, mechanically clean the surface using a steel brush, sanding disc, or other appropriate methods to remove loose particles, dirt, and debris.
• Although DOWSIL™ 786 Silicone Sealant is compatible with a wide variety of materials, we recommend testing adhesion on a small area to ensure compatibility, especially when working with coated or special finishes.
• Priming may be required for some surfaces, particularly porous ones, to maximize adhesion.
• To ensure a neat and clean application, mask areas adjacent to the joint with tape to prevent contamination of the substrates. This will also help achieve a straight and professional-looking sealant line.
• Remove the masking tape immediately after tooling the sealant for a crisp, clean edge.
• Always ensure adequate ventilation when using any solvent-based cleaning products or working in confined spaces. This helps to maintain a safe working environment and improve the curing process.
• Dowsil 786 adheres to a variety of substrates. Primers are not usually required but might be needed for some specific substrates to achieve maximum adherence. Users must carry out their own tests due to the wide variety of substrates available.

Application

If possible test on a small area before you start to ensure compatibility.

• When back-up material is required, use a closed-cell polyethylene backer rod. This will help prevent three-sided adhesion, which could limit the sealant's movement capabilities.
For joints too shallow to accommodate a backer rod, use low-tack polyethylene tape as an alternative.
• After cutting the tip of the cartridge, screw the nozzle onto the cartridge and cut the end of the nozzle at a 45° angle to the required bead width.
• Apply DOWSIL™ 786 Silicone Sealant into the joint or gap, ensuring a continuous, uniform bead. For best results, use an air-operated caulking gun or bulk dispensing equipment. Such as Geocel Cox Skeleton Gun.
• Apply the sealant using consistent pressure to ensure full coverage and avoid air pockets.
• Tool the sealant within 5 minutes of application to ensure good contact between the sealant and the substrate.
• Use light pressure to smooth the sealant and spread it evenly across the joint. This helps to ensure a smooth, professional finish for best results use Bedec Silicone Profilers.
• Remove the masking tape immediately after tooling the sealant to leave a clean, crisp edge and prevent the tape from bonding to the sealant.
• Allow the sealant to cure fully at room temperature. DOWSIL™ 786 Silicone Sealant is a neutral-curing sealant, meaning it will cure by reacting with moisture in the air.
• Curing times vary depending on ambient conditions, but typically, the sealant will be touch-dry within 20-30 minutes and will fully cure in approximately 24 hours, depending on joint depth and environmental conditions.
• Ensure that the joint design accommodates the movement capability of the sealant. The minimum joint width for DOWSIL™ 786 Silicone Sealant should be 6 mm.
• For joints between 6–12 mm wide, the seal depth should be 6 mm.
• For joints wider than 12 mm, use a width-to-depth ratio of 2:1 for optimal performance.

Always follow manufacturers instructions found on the packaging.

Aftercare & Storage

This product has a usable life of 810 days from the date of production when stored in cool, dry conditions below 32°C in the original unopened containers.