Patterned Adhesive Unit for Rollable Display Stress Management

The patent changes the physical parameter of the adhesive unit by introducing a patterned base layer with reduced modulus compared to conventional adhesive units. This modulus reduction allows the adhesive unit to better accommodate stress during rolling and unrolling operations, preventing cracks while maintaining adequate bonding strength. The patterned structure with varying thickness or material composition enables localized stress distribution that resolves the contradiction between bonding strength and durability.

The adhesive unit is constructed as a composite structure comprising a patterned base layer and adhesive layers. The base layer incorporates patterns (such as ridges, grooves, or varying thickness regions) that create a composite material system with tailored mechanical properties. This composite structure combines regions of different stiffness, allowing the adhesive unit to provide strong bonding where needed while maintaining flexibility and stress resistance in other areas, thus resolving the contradiction between bonding strength and reliability during repeated rolling.

The patterned base layer introduces local quality variations within the adhesive unit, creating regions with different mechanical properties. The patterns (ridges, grooves, or thickness variations) provide localized flexibility in certain areas to reduce stress concentration during rolling, while maintaining structural stability in other regions. This spatial variation in material properties allows the adhesive unit to simultaneously achieve structural stability and stress resistance, resolving the contradiction between these two requirements.

The base layer is segmented into a patterned structure with multiple regions of different thickness or material composition. This segmentation divides the adhesive unit into functional zones that can independently respond to stress during rolling operations. The segmented patterned structure prevents stress concentration by distributing mechanical loads across multiple regions, thereby maintaining structural stability while reducing harmful stress effects that would otherwise cause cracks.

The patterned base layer segments the adhesive application areas, creating defined regions where adhesive material is confined. The patterns (such as ridges or enclosed structures) act as physical barriers that contain the adhesive within specific zones, preventing it from leaking through openings in the cover. This segmentation allows sufficient adhesive coverage for complete bonding while eliminating the harmful effect of adhesive leakage by restricting the adhesive to designated areas.

The patterned structure creates local quality differences in the base layer, with certain regions designed to contain adhesive material. These patterned regions provide localized confinement that ensures adequate adhesive coverage for bonding while preventing adhesive from migrating to areas where it would leak through cover openings. The local quality variations in the patterned base layer thus simultaneously achieve complete bonding coverage and prevent adhesive leakage.