Joint dimensions:

The movement capability of sealants as well as local regulations must be considered. Joint width should be twice the depth.

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 solvent soaked cloth and then wiped with a clean cloth. To remove dust, use oil-free compressed air.


Although BLUESIL SLT 3E 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


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 like BLUESIL SILICONE REMOVER.

BLUESIL SLT 3E BLACK may be stored at temperatures between -5°C / 23°F and 50°C / 122°F for up to 24 months from its date of manufacturing.Please consult the Safety Data Sheet of this product.


BLUESIL SLT 3E is a one-component silicone sealant which, when exposed to atmospheric humidity, forms a flexible and durable elastomeric seal which possesses excellent resistance to severe weathering conditions.


1 Part RTV Acetoxy

BLUESIL SLT 3E bonds well to clean uncoated glass, ceramics, most glazed non-porous surfaces and anodized aluminium without the need to prime. The rheological properties of BLUESIL SLT 3E allow high rates of extrusion whilst the thixotropy enables the sealant to be used on vertical jointing and underside applications.


BLUESIL SLT 3E presents excellent stability to temperature variations (-30 °C to+120 °C), UV rays, rain, snow...

BLUESIL SLT 3E is a general purpose silicone sealant which offers good performance on many different applications where weathertightness is required:

  • Caulking doors and windows.
  • Shop windows, display cases, panels and signs.
  • Plumbing, drains, guttering.
  • HVAC ducting.
  • Sealing of electrical conduit.
  • Boat maintenance.
  • DIY general purpose sealing.

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




Elongation450MonocompNF ISO 37%
Hardness20MonocompISO 868sh.A
Tensile strength1.8MonocompNF ISO 37MPa