The substrate must be sound, clean, dry and free of all contaminants such as dirt, oil, grease, old sealants and poorly bonded paint coatings which could affect adhesion of the sealant. The substrate must be of sufficient strength to resist the stresses induced by the sealant during movement.
All dust, loose and friable material must be completely removed from all surfaces using suitable equipment before application of any activators, primers or sealant. Sikasil®-129 Kitchen & Bathroom Transparent adheres without primers and/or activators.
For optimum adhesion, joint durability and critical, high performance applications such as joints on multi-storey buildings, highly stressed joints, extreme weather exposure or water immersion / exposure, the following priming and/or pre-treatment procedures must be followed:
Non-porous substrates
Aluminium, anodised aluminium, stainless steel, PVC, galvanised steel, powder coated metals or glazed tiles. Slightly roughen surface with a fine abrasive pad. Clean and pre-treat using Sika® Aktivator-205 applied with a clean cloth.
Before sealing, allow a waiting time of > 15 minutes (< 6 hours).
Other metals, such as copper, brass and titanium-zinc, clean and pre-treat using Sika® Aktivator-205 applied with a clean cloth. After a waiting time of > 15 minutes (< 6 hours), apply Sika® Primer-3 N by brush. Before sealing, allow a waiting time of > 30 minutes (< 8 hours).
PVC has to be cleaned and pre-treated using Sika® Primer-215 applied with a brush. Before sealing, allow a waiting time of > 30 minutes (< 8 hours).
Glass must be cleaned with Isopropanol before application.
Porous substrates
Porous substrates must be primed using Sika® Primer-3 N applied by brush.
Before sealing, allow a waiting time of > 30 minutes (< 8 hours).
Adhesion tests on project specific substrates must be performed and procedures agreed with all parties before full project application.
For more detailed advice and instructions contact Sika Technical Services.
Note: Primers and activators are adhesion promoters and not an alternative to improve poor preparation / cleaning of the joint surface. Primers also improve the long term adhesion performance of the sealed joint.