Release-Layer and Demoulding-Surface Engineering for Photocurable Processes: Interfacial Energy, Wear, Fouling and Transfer Fidelity

A release film, coated vat window or demoulding surface in a photocurable process is a functional interface whose behaviour cannot be reduced to low surface energy. Separation force also depends on cured area and geometry, resin viscosity, degree of conversion, fluid drainage, lift trajectory, support compliance and deformation. Where the window controls light transmission or oxygen delivery, the release construction also alters cure and dimensional fidelity. With use, wear, scratching, swelling, clouding, fouling and additive depletion can change these coupled functions before catastrophic failure occurs. This review defines a qualification architecture for release surfaces used in vat photopolymerisation, photocurable replication and adjacent demoulding processes. It requires identity, thickness, support, compliance, texture, optics and oxygen transport to be specified; separates adhesion, suction or hydrodynamic pressure, deformation and cure-shrinkage contributions; pairs separation force with part fidelity and residue inspection; and follows functional drift over counted cycles. Replacement is based on application-specific drift from a validated baseline rather than a universal cycle count. The evidence does not establish a commercial film, coating recipe, force limit, lift setting, dead-zone dimension, service interval or life prediction.