For external joints and bonding of plastic windows in marine applications Sikaflex®-295 UV is a non-sag 1-K polyurethane-based adhesive that dries with the influence of atmospheric humidity. The product is suitable for use in internal and external sealing applications and for bonding plastic windows in marine applications. Sikaflex®-295 UV meets the requirements of the International Maritime Organization (IMO) flame spread test.
Sikaflex®-295 UV has been specially developed for use in the marine industry to bond and seal plastic windows in boats and ships. Due to its excellent weather resistance, the product is also suitable for use in external sealing joints. Suitable material surfaces include aluminium (clear or anodised), reinforced plastic (polyester resin), stainless steel, wood, 2-component coatings and plastic windows (Polycarbonate PC, Acrylic PMMA). Please read the manufacturer's instructions and carry out tests on original material surfaces before using Sikaflex®-295 UV on plastic grades that are sensitive to stress cracking. This product is intended for professional use only. The product should be tested on actual material surfaces and operating conditions to ensure adhesion and compatibility properties.
Surface preparation
Surfaces must be clean, dry and free from grease, oil, dust and contaminants. Surface adhesion treatments depend on the properties of the material surfaces and are crucial for the long-term performance of the adhesive bond. Suggestions for adhesion treatments can be found in the current Sika® Pre-Treatment Chart for the product range. Please note that the adhesion treatment suggestions given are based on practical experience and must be confirmed by performing adhesion tests on the material surfaces to be used.
Application
Sikaflex®-295 UV can be applied in a temperature range of 10 °C – 35 °C (environment and product), taking into account the effect of the prevailing temperature on the reactivity of the adhesive mass and the application properties. The recommended bonding temperatures (material surfaces, air and adhesive mass) are between 15 °C – 25 °C.
Please note that the viscosity of the adhesive increases at low temperatures. To ensure easy application, the product temperature should correspond to the ambient conditions before use. To ensure sufficient layer thickness of the adhesive joint, we recommend applying the joint with a triangular cross-section.
Diffusion
It is recommended to use a powerful piston-operated gun (manual, pneumatic or battery-operated) or a pump device to dispense Sikaflex®-295 UV. The open time of the adhesive is significantly shorter in warm and humid air. Bonding should always be carried out within the open time. Never bond if the joint surface has already become skinned.
Seam finishing
The joint must be finished within the open time specified for the product. The recommended finishing agent is Sika® Tooling Agent N. The user must check/ensure the suitability/compatibility of other finishing agents before use.
Stain removal
Uncured Sikaflex®-295 UV can be removed from tools and equipment with Sika® Remover-208 or another suitable solvent. Once dried, the product can only be removed mechanically. Hands and other contaminated skin should be cleaned immediately with Sika® Cleaner-350H or a suitable industrial detergent and water (no solvents).
Overpainting
Sikaflex®-295 UV can best be overcoated within the skin time. If overcoating is done after the surface of the compound has dried, the adhesion of the paint to the joint can be improved by wiping it with Sika® Aktivator-100 or Sika® Aktivator-205 beforehand. If the painting process requires baking (> 80 °C), the best result is achieved by letting the compound dry through first. Overcoating tests should be carried out in advance on the customer's painting line for all paint types intended for use.
The elasticity of a dried paint film is usually lower than that of the sealant, which can lead to the paint film breaking in the expansion joint area.