The backing adhesive system of acrylic stickers: Adhesion principles and types

The backing adhesive is the core component that enables the sticking function of acrylic stickers. Its performance directly determines the usage effect and lifespan of the product. The commonly used type of backing adhesive for acrylic stickers is acrylic pressure-sensitive adhesive. This is a type of adhesive that can achieve adhesion by simply applying a light pressure without the need for solvents, heating, or pressure.

Adhesion principle: The molecular chains of acrylic pressure-sensitive adhesive have high flexibility and moderate crosslinking degree. They can smoothly level out the unevenness of the surface of the adherend at the microscopic level. Through van der Waals forces, they form physical adsorption. This type of bonding is reversible - when pressure is applied, the molecular chains flow, forming contact; when the pressure is removed, the elastic restoring force of the molecular chains enables the adhesive layer to have a certain cohesive strength, resisting peeling.

Performance features: The temperature resistance range of acrylic pressure-sensitive adhesive is typically between -20°C and 120°C. It can withstand a short-term temperature of 150°C. It has excellent chemical resistance and can resist most acid, alkali, salt solutions and organic solvents well. In outdoor applications, the anti-ultraviolet aging performance of the acrylic adhesive layer far exceeds that of natural rubber systems, and it is less likely to harden or crack.

Type classification: Based on the bonding strength and application scenarios, it can be divided into:

Permanent fixed type: High peel strength (>12N/25mm), suitable for applications requiring long-term fixation, such as nameplates and signs. Residual adhesive marks may remain after removal.

Removable type: Utilizing microsphere technology or low-viscosity formula, there will be no residue glue after removal, suitable for temporary signs and promotional stickers.

High viscosity elastic type: Foam base acrylic tape, capable of absorbing vibrations and thermal expansion/contraction stresses, suitable for automotive trim pieces and outdoor equipment fixation.

Usage Notes: Before pasting, ensure that the surface to be adhered is clean, dry, and free of oil stains. The optimal construction temperature is between 15°C and 35°C. If the temperature is too low, the adhesive layer will become hard and the initial adhesion force will decrease. After pasting, the final bonding strength will reach over 90% of the maximum strength within 24 hours. During this period, avoid moisture or force.