Most self-adhesive tapes consist of a backing and an adhesive layer. Additional layers can provide protection, reinforcement or grip. When choosing tape, it is therefore important to consider the complete construction: this determines how the tape adheres, how it handles and how it performs during use.
The components of tape
The backing gives tape its shape and mechanical properties. It may consist of film, paper, fabric, foam or another material construction. The backing influences properties such as flexibility, tearability, elongation and ease of application.
The adhesive layer makes contact with the substrate and holds the tape in place. Its formulation and layer construction determine how quickly the tape sticks, how adhesion develops and how the bond responds to loads.
Some tapes have a release liner: a removable protective layer that covers the adhesive until it is used. This is common with double-sided tape and adhesive transfer tape. Reinforcing threads, a foam core or a textured, non-slip surface provide additional functions in specialist tapes.
Single-sided, double-sided and adhesive transfer tape
Single-sided tape has an adhesive layer on one side of the backing. This is the familiar construction used for packaging tape, masking tape and duct tape, for example.
Double-sided tape has an adhesive layer on both sides. The release liner protects the adhesive during storage and helps with positioning. The choice depends on the materials, the required bond and the assembly method.
Adhesive transfer tape consists of an adhesive layer on a removable release liner, without a separate backing. This allows thin bonds that conform to the shape of a surface. During application, the adhesive layer is supported by the material to which the tape is applied.
Self-amalgamating tape
Self-fusing or self-amalgamating tape can be constructed without a separate adhesive layer. When wrapped, the overlapping layers bond to one another. This construction requires the appropriate application method, including the specified stretch and overlap.
What does tape thickness mean?
Total thickness describes the complete tape construction. Depending on the product, this includes the backing and adhesive, and sometimes an additional layer. A value for the backing alone is therefore different from the total thickness. A removable release liner is generally excluded from the stated tape thickness; the measurement definition specifies which layers are included.
Thickness is often expressed in micrometres (µm). One micrometre is 0.001 millimetres. A tape measuring 50 µm is therefore 0.05 mm thick. Specialist tapes, such as anti-slip tape with a granular top layer, can have a considerably thicker overall construction.
A thicker tape is not automatically stronger or better. The application determines which combination of backing, adhesive layer and thickness is suitable. For packaging, factors include closure performance and processing speed; for mounting, the substrate, loads and required bond are decisive.
Comparing thicknesses
Compare thicknesses using the same measurement definition: total tape thickness, backing thickness or adhesive layer thickness. The measurement method and any measurement limits also form part of the specification. This prevents two different quantities from being treated as directly comparable.
An adhesive coat weight in g/m² indicates the mass of adhesive per unit area. It is not a measurement of thickness. Converting it to a layer thickness depends on factors including the density of the material.
The right construction for your application
Van Loenhout Products helps you match the tape construction to its purpose, substrate and application method. We consider the backing, adhesive type, dimensions and loads together. For specific requirements, we also discuss alternative constructions or custom-made options.
