Sikaflex®-255 Ultra
OEM approved and no odor Auto Glass Adhesive
Sikaflex®-255 Ultra is a cold applied windscreen adhesive, optimized for manual application. It provides a long open time and ensures safe application even under warm conditions. Sikaflex®-255 Ultra is compatible with Sika's Black Primerless and All Black processes and may also be used as a primerless to glass adhesive in auto glass replacement applications. Note: Primerless to glass application requires the glass to be prepared using an Automotive grade glass cleaner such as Sika® Cleaner G+P. The bonding surfaces must be free of contamination and have sufficient UV protection.
- Easy to extrude with manual application gun
- Solvent free, no odor
- OEM approved adhesive system
- Fast adhesion build up
- Primerless to glass adhesion
PRODUCT BENEFITS
- Easy to extrude with manual application gun
- Solvent free, no odor
- OEM approved adhesive system
- Fast adhesion build up
- Primerless to glass adhesion
Areas of Application
Sikaflex®-255 Ultra is suitable for experienced professional users only. This product and related process information is designed for Automotive Glass Replacement. For other applications, tests with actual substrates and conditions have to be performed ensuring adhesion and material compatibility.Product Details
Chemical base | 1-component polyurethane | |
Color (CQP001-1) | Black | |
Cure mechanism | Moisture-curing | |
Density (uncured) | 1.31 kg/l | |
Non-sag properties (CQP061-1) | Good | |
Application temperature | product ambient | 5 – 40 °C 5 – 40 °C |
Skin time (CQP019-1) | 40 minutes A | |
Open time (CQP526-1) | 30 minutes A | |
Curing speed (CQP049-1) | (see diagram) | |
Shore A hardness (CQP023-1 / ISO 48-4) | 50 | |
Tensile strength (CQP036-1 / ISO 527) | 5 MPa | |
Elongation at break (CQP036-1 / ISO 527) | 500 % | |
Tear propagation resistance (CQP045-1 / ISO 34) | 12 N/mm | |
Tensile lap-shear strength (CQP046-1 / ISO 4587) | 3 MPa | |
Minimum Drive Away Time (cars) according FMVSS 212 (CQP511-1) | with airbags | 3 hours A/B |
Shelf life | 9 months C |
CQP = Corporate Quality Procedure | A) 23 °C / 50 % r. h. | B) Details about MDAT contact Sika | C) storage below 25 °C |
CURE MECHANISM
Sikaflex®-255 Ultra cures by reaction with atmospheric moisture. At low temperatures the water content of the air is generally lower and the curing reaction proceeds somewhat slower (see diagram 1).
Diagram 1: curing speed Sikaflex®-255 Ultra
CHEMICAL RESISTANCE
Sikaflex®-255 Ultra is generally resistant to fresh water, seawater, diluted acids and diluted caustic solutions; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and caustic solutions or solvents.
Application
Surface preparation
Surfaces must be clean, dry and free from grease, oil, dust and contaminants.
The bond faces must be prepared with an Automotive grade glass cleaner such as Sika®Cleaner G+P.
Sikaflex®-255 Ultra is capable to bond on glass and ceramic frits without additional pre-treatment. It is compatible with Sika's Black-Primerless or All Black installation process for best results.
Further information on the application and use of pre-treatments, can be found in the corresponding Product Data Sheet.
Note: Glass without ceramic coatings need proper UV protection.
Application
Sikaflex®-255 Ultra can be processed between 5 °C and 40 °C but changes in reactivity and application properties have to be considered. The optimum temperature for substrate and adhesive is between 15 °C and 25 °C.
Consider that the viscosity will increase at low temperature. For easy application, condition the adhesive at ambient temperature prior to use. To ensure a uniform thickness of the bondline it is recommend to apply the adhesive in form of a triangular bead (see figure 1).
Figure 1: Recommended bead configuration
The open time is significantly shorter in hot and humid climate. The glass must always be installed within the open time. Never install a glass after the adhesive has built a skin.
Removal
Uncured Sikaflex®-255 Ultra may be removed from tools and equipment with Sika® Remover-208 or other suitable solvents. Once cured, the material can only be removed mechanically. Hands and exposed skin have to be washed immediately using hand wipes such as Sika® Cleaner-350H or a suitable industrial hand cleaner and water.
Do not use solvents on skin.