Joint preparation:

The joint faces to be bonded must be clean, dry and free from dust, oil, grease, old sealant and any traces of contaminant which may affect adhesion. Surfaces should be degreased with a solvent soaked cloth and then wiped with a clean cloth. To remove dust, use oil-free compressed air.


Although BLUESIL SLT 4S will bond well to most clean and dry surfaces, it is recommended that a primer be used on certain substrates in order to ensure a strong and uniform bond :

  • Steel, ferrous metals, thermoplastic materials........... BLUESIL PRIM 10073
  • Concrete, stone, wood............................................ BLUESIL PRIM 12076

On non-porous substrates, the primer should be applied with a cloth or soft brush in a thin and uniform film. On porous substrates apply with a brush; in the case of particularly porous material apply a second layer after drying.

Sealant application:

For good performance it is essential that the sealant be only bonded to the two facing sides of the joint ; to achieve this, install a backup material (closed cell polyethylene or open cell polyurethane foam). Apply the sealant in a continuous operation, making sure that all air pockets or voids are eliminated. Tool the sealant with light pressure to spread the material against the joint surfaces. This operation should be made with a dry spatula before skin formation occurs.

Excess uncured sealant should be wiped and cleaned with a commercial solvent.

Cured sealant can only be removed by scraping (i.e. with a razor blade), or with a special silicone remover product.

BLUESIL SLT 4S TRANSCLUCENT may be stored for up to 15 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.VOC;RoHS


BLUESIL SLT 4S is a one-component, moisture-cure silicone sealant which contains a fungicide. It cures at room temperature to form a flexible, low modulus watertight joint for general sanitary sealing.


1 Part RTV Acetoxy



​BLUESIL SLT 4S has been specifically formulated as a sanitary sealant for use in hot humid environments such as kitchens and bathrooms where resistance to fungal growth is necessary.

BLUESIL SLT 4S is very easily extruded and has the advantage of virtually no stringiness. Its rapid curing characteristics enable units to be quickly sealed and put into service. Its smooth, glossy appearance compliments glazed sanitary ware and ceramic tiles.

BLUESIL SLT 4S adheres without primer to clean uncoated glass, ceramics, vitreous surfaces and anodized aluminium. For most other substrates it is recommended that a primer be used, a range of high performance primers is available which will ensure optimal bonding to most commonly encountered substrates.

It offers good resistance to most common cleaning products. BLUESIL SLT 4S has also good resistance to the temporary action of many diluted acids and bases as well as salt spray. However, exposure to solvents and especially hydrocarbons will lead to some reversible swelling and softening. Upon prolonged exposure, loss of adhesion will occur.

The exceptional translucency of BLUESIL SLT 4S is such that it is ideally suited for use where the sealant is visually prominent.

​BLUESIL SLT 4S can be used on all weatherproofing or bonding applications where protection against fungal growth is sought, such as:

  • Jointing baths, sinks, showers, kitchen furniture, urinals...
  • Jointing ceramic tiles, plumbing fixtures or cold rooms.

North America;Europe Middle East Africa;Central and South America;Asia Pacific




Elongation470MonocompNF ISO 37%
Tensile strength1.2MonocompNF ISO 37MPa