Abstract: Widespread folding creases in flexible screens can be improved through the design of OCA (Optical Clear Adhesive) layers. For extremely thin OCA layers, finite element simulations require extremely dense meshing, resulting in significant computational costs and even rendering the problem incalculable. This paper proposes a three-dimensional interface element for OCA layers, which significantly improves computational efficiency while maintaining accuracy, enabling the simulation of large-scale flexible, rollable screens with ultra-thin adhesive layers. Based on considerations of viscoelasticity, plasticity and geometric nonlinearity, the paper simulates the process of crease formation in foldable screens and studies the impact of OCA layer design parameters on residual stress and creases in foldable screens.