Pressure sensitive adhesive polymer

At present, with the advent of the full screen era and even the foldable era of mobile phones, coupled with the Internet of Everything era triggered by 5G, the screen is used in more and more scenarios, and the glass panel used is getting bigger and thinner, so the probability of falling behind and breaking in the process of use is also increasing. Cushioning and damping for these electronic devices with screens has always been a hot research topic.

At present, there have been some beneficial tape inventions, such as foam tape of PE, PU, acrylic and other material substrates, VHB tape of 3M company, etc., these pressure-sensitive adhesive products (for example, Pressure sensitive tape) through the base material of foaming material or adhesive itself to produce foaming gap or add hollow microspheres to provide better buffering effect.

However, the current use of acrylic adhesives or rubber adhesives to improve the buffering and anti-fall effect, the internal addition of polymer foam particles, glass microspheres, expansive polymers, or filled with gas to form bubbles, then coated with adhesive film, because of the existence of bubble holes and has good buffering and anti-fall effect. However, the addition of foaming particles, glass microspheres, expandable polymers and so on has serious control over the proportion of addition, the size and number of bubble holes, the stability of each process, the dispersion of additives are relatively difficult, the process is complex, resulting in high production costs, and because of the existence of these additives, there are requirements for the thickness of the final adhesive layer. At present, the lower limit of the mainstream thickness is more than 100μm.

For the adhesive coating on the foam substrate layer, through the buffer effect of the foam substrate to anti-fall effect, in order to make double-sided tape, two gluing processes are needed, reduce the processing efficiency, increase the cost; In addition, the multi-layer structure can not meet the requirements of thin shape, and it is difficult to control the total thickness below 100μm on the premise of ensuring the high viscosity and high buffering effect.