The two forces of cohesion and adhesion are the basis for the adhesive power of an adhesive/adhesive tape.
Adhesion causes the adhesive tape to adhere to the substrate. The forces acting in this process are greater the closer the two surfaces are to each other. The strength of the bond is directly dependent on the contact that the adhesive has with the surface, therefore a significant improvement is achieved by bonding under pressure (with squeegee). In addition, the adhesion of the surfaces to be bonded can be improved by using primers (adhesive promoters).
Cohesion describes the property of the adhesive to have a mechanical stability in itself. Honey" is an extreme example of an adhesive with low cohesion. In this case, good adhesion (tackiness) is paired with low cohesion (soft, flowing). The adhesive strength to the substrate increases over time.
Good bond strength values are already achieved within 10 minutes, after 24 hours the final values are usually almost reached. Moderate heating (e.g. to 70°C) shortens this time by accelerating surface wetting.
Learn here more about the properties and application areas of our different adhesive types such as: Acrylic Adhesives, Polysiloxane Adhesives, Rubber Adhesives, Heat Seal Adhesives, Hot Melt Adhesives and Liners.
Cohesion and adhesion