SikaMelt®-285 Primer
Hot melt primer for foam injected panels
SikaMelt®-285 Primer is a thermoplastic hot applied primer product with 100 % solids content. It is formulated as an adhesion promoter for foam injected panels.
- Solvent and Isocyanate free
- Good adhesion on metals and plastics
- High cohesion
- Very high heat resistance
- Good hydrolysis resistance
PRODUCT BENEFITS
- Solvent and Isocyanate free
- Good adhesion on metals and plastics
- High cohesion
- Very high heat resistance
- Good hydrolysis resistance
Areas of Application
SikaMelt®-285 Primer is used to give improved adhesion of injected foams to coated and bare metallic and various plastic surfaces. The product is designed as an alternative to isocyanate primer systems used for foam injected panels. SikaMelt®-285 Primer is not suitable for substrates containing monomeric plasticizer. This product is suitable for experienced professional users only. Test with actual substrates and conditions have to be performed to ensure adhesion and material compatibility.Product Details
| Chemical base | Thermoplastic rubber | |
| Color (CQP001-1) | Light honey color, clear or opaque | |
| Cure mechanism | Physical hardening | |
| Density | 1 kg/l | |
| Viscosity (by Brookfield) | at 190 °C | 7 000 mPa·s |
| Softening temperature (CQP538-5) | 132 °C | |
| Application temperature |
short term max. 1 hour | 170 ─ 190 °C 200 °C A |
| SAFT (CQP560-1) | 100 °C | |
| Coverage | 30 – 50 g/m2 | |
| Shelf life | 12 months |
| CQP = Corporate Quality Procedure | A) only valid for nozzle |
CURE MECHANISM
SikaMelt®-285 Primer is a physically hardening primer.
CHEMICAL RESISTANCE
SikaMelt®-285 Primer is resistant to aqueous surfactant solutions, weak acids and caustic solutions.
The chemical resistance is influenced by several factors such as chemical composition, concentration, period of exposure and temperature. Therefore a project related testing in case of chemical or thermal exposure is required.
Application
Surface preparation
Surfaces must be clean, dry and free from grease, oil and dust.
Based on the surface and type of material, a physical or chemical pre-treatment might be required. Type of pre-treatment must be determined by preliminary tests.
Application
SikaMelt®-285 Primer is applied directly on the substrate. It can be applied as film or by spray application.
For automated applications a suitable filter system is required.
To meet the required application properties the adhesive viscosity can be adjusted by adapting the application temperature (see diagram 1).
Diagram 1: Viscosity as function of temperature
During breaks SikaMelt®-285 Primer is to be processed as follows:
For breaks ≥ 1 h the heating needs to be lowered to 80 °C and for breaks ≥ 4 h the heating needs to be switched off.
To guarantee a constant quality during the whole production process it is recommended to protect the adhesive in the melting tank with nitrogen or carbon dioxide (to avoid possible reaction of the product with oxygen).
For advice on selecting and setting up suitable processing equipment contact the System Engineering Department of Sika Industry.
Removal
SikaMelt®-285 Primer may be removed from tools and equipment with Sika® Remover-208 or another suitable solvent.
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.
STORAGE CONDITIONS
SikaMelt®-285 Primer has to be stored at temperature below 40 °C in a dry place.
For transportation purposes, the storage temperature can be exceeded for a period of max. 4 weeks up to 60 °C.