▎ 摘　　要

NOVELTY - A component comprises an integrally formed non-uniform lattice structure containing a repeating unit cells (R1) and (R2) which are different. USE - Component e.g. permeate-backing layer used in envelope of spiral wound membrane for treatment module used for water filtration (all claimed) such as ultrafiltration, microfiltration, nanofiltration, and reverse osmosis. ADVANTAGE - The component is inexpensive and has excellent chemical, mechanical and thermal stability, good fouling resistance with cleanability, long life span, high permeability and controllable selectivity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: permeate-backing layer; membrane envelope; piral wound membrane; water treatment module; and preparation of the component.