CERESIT CS25 Antracite is a sanitary silicone sealant supplied in a 280 ml cartridge and formulated for sanitary and bathroom joints. The sealant is designed to produce durable, flexible seals in wet environments where resistance to mold and mildew is important. The antracite color matches darker tiles and fixtures, providing a discreet, watertight finish around sinks, bathtubs, showers, tile edges and plumbing connections.
Advantages
The product offers mildew-resistant formulation intended for long-term use in humid areas. Its elastic silicone composition accommodates small movements in joints while maintaining a reliable water barrier. The ready-to-use cartridge format is compatible with standard caulking guns, enabling controlled application and consistent bead shape. The dark antracite shade minimizes visible staining on dark tiles and grout lines and helps maintain a uniform appearance in bathrooms and kitchens.
Suitable for
- Sealing joints around bathtubs, showers and washbasins
- Filling perimeter joints between tiles and sanitary fixtures
- Sealing plumbing penetrations and connections in wet rooms
- Repairing existing deteriorated silicone joints where mold resistance is required
When it may not be suitable
This sanitary silicone is intended specifically for sanitary and bathroom applications; it is not recommended for structural glazing, load-bearing connections or where mechanical fastening is required. It may not adhere well to surfaces contaminated with grease, silicone residue or loose paint; proper surface preparation is necessary. Avoid using it on natural stone surfaces that are sensitive to acetic-cure silicones unless compatibility is verified.
Key specifications
- Color: antracite (dark grey)
- Volume: 280 ml cartridge
- Product type: sanitary silicone sealant with mould-resistant formulation
- Curing: neutral/acetic-cure characteristics typical of sanitary silicones (skin formation and full cure times depend on ambient conditions)
- Elasticity: permanently flexible joint suitable for small movement accommodation
- Application temperature range: suitable for typical indoor bathroom conditions (refer to technical datasheet for exact limits)
How to use
Ensure surfaces are clean, dry and free of dust, grease and old sealant. Cut the cartridge tip to the desired bead size and load into a standard caulking gun. Apply an even bead of sealant into the joint, maintaining consistent pressure. Smooth the bead within the manufacturer’s recommended tooling time using a compatible smoothing tool or a wetted finger to ensure adhesion and a neat finish. Allow the joint to cure fully before exposing it to continuous water contact; curing time varies with temperature and humidity.
What to consider before purchase
- Confirm color match with tiles and fixtures; antracite is a dark grey tone
- Check surface compatibility, especially with natural stone and newly painted surfaces
- Verify required cartridge volume and number of joints to be sealed
- Consider ventilation and curing conditions in the installation area
Usage recommendations
For best performance, remove old silicone fully and use an appropriate primer on non-porous or difficult substrates if indicated by the manufacturer. Store cartridges in a cool, dry place and use within the shelf-life stated on the packaging. Follow local disposal regulations for empty cartridges and excess sealant.
