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Sika 206 GP Substrate Primer (B) 250ml
£41.77 Excl VAT
FAQs
What are the Characteristics of Primers?Primers can be solvent and water-based, with an active additive dissolved in a solvent, alcohol or water solution to aid application. Solvent based primers dry quickly whereas water based primers can take significantly longer. The relative humidity and ambient air temperature usually determine the drying time, which can take anything from 5 minutes to several hours dependant on the type of primer used and the surfaces to which they are applied.
You can use adhesive primers on vertical or horizontal surfaces, but as many are low viscosity solutions, consideration of practicality need to be assessed. Surfaces such as glass, metals, composites, rubber, plastics, concrete, wood and other common engineered surfaces may require use of a primer or adhesion promoter to ensure good long-term adhesion.
It is important to keep in mind that primers are not a substitute for surface cleaning and preparation. The surface must be freshly cleaned and free of dirt, grease and other debris. For optimal adhesion, it is also necessary to apply a primer that’s compatible with the coating.
Strengthens adhesion
The primary benefit of a bonding primer or adhesion promoter is that it enhances adhesive properties. When a primer is applied, a stronger bond is formed between the coating and the substrate. By using primers on your bonded surfaces this will maximise their long-term durability and provide the optimum adhesion properties for the adhesive/sealant used.
Protects from dirt and dust
Adhesive primers ensure a tight seal between a substrate and a coating. By doing so, the primer helps keep subsequent layers free of microscopic dust that can damage the final output. To help the adhesive primer perform at its best, when preparing the surface don’t forget to eliminate contaminants as much as possible.
Helps deal with various materials, especially difficult-to-bond ones
Adhesives are often designed to adhere to a wide range of surfaces, but under certain conditions, not all of them will perform as well as they should due to the type of surface being bonded. For Example, even strong industrial glues can struggle when temperatures stay below freezing or on substrates that are difficult to bond where they have surface contaminants or plasticisers. These materials include acetal, diene rubber, polypropylene, fluoropolymers, PET, plasticised plastics, polyethylene or other low surface energy plastics. There are very few industrial adhesives capable of providing long-lasting bonding to these surfaces without the need for surface preparation or priming.
Primers can help with these type of situations, the primer serves as a preparation for the bonding agents, which can then make the bonds stronger, enhancing the function of the adhesives more effectively.
First, choose an adhesive or bonding primer that is compatible with the adhesive/sealant chemistry type being utilized and one to meet your application requirements. It is always important to consider the surface and environment you are working on.Â
For bonding to work, surfaces must be clean. They also must be smooth, dry and free from contaminants such as grease, wax and oil.Â
Ideally surfaces should be pre-cleaned with a solvent/alcohol based cleaner or a suitable water based solution, followed by light abrasion to eliminate loose materials on surfaces, with a final clean to remove residues.
Once you have completed preparing the surface, take the primer (if you’re using a can version) and thoroughly shake it. Then, spread a thin but sufficient layer using an applicator pad or wipe, do not over apply, any excess should be removed and allowed to dry fully before the adhesive/sealant is applied.
It’s essential to check the manufacturer’s guidelines for the ideal application and surface temperature, as well as how many times it should be applied. Also take note that warm materials are more easily adhered to adhesive than cold materials. As a result, acclimatizing materials and environments is also of paramount importance. After applying the primer, ensure that the container is tightly closed.