For proper adhesion, what is a requirement regarding the surface when using certain adhesives?

For proper adhesion when using certain adhesives, having a clean and dry surface is crucial. Adhesives need to bond effectively to the material they are applied to, and any contaminants such as dust, oils, or moisture can interfere with that bond. A clean surface ensures that the adhesive can make good contact with the substrate, allowing for a strong and reliable connection.

The surface being dry is equally important because excess moisture can compromise adhesion; it can either prevent the adhesive from curing properly or lead to a weak bond. Additionally, certain adhesives are formulated to work best on substrates that do not have any residual moisture. Thus, maintaining cleanliness and dryness of the surface facilitates the best possible adhesion outcomes. Other options, while they may have their own contexts, do not directly address the core requirement for a strong adhesive bond as effectively as a clean and dry surface does.