▎ 摘　　要

NOVELTY - Sealing layer (230) comprises: 30-70 wt.% water-soluble poly(vinyl alcohol) homopolymer or poly(vinyl alcohol-co-ethylene) copolymer having degree of hydrolysis of 90-99.5%, and ethylene content of less than 10%; and 7-29 wt.% polyurethane having interfacial tension of less than 2 mN/m with water-soluble polyvinylalcohol homopolymers or copolymers. The polyuretherane is crosslinked by crosslinker. The crosslinkers are polyisocyanate, multifunctional polycarbodiimide, multiffunctional aziridine, silane coupling agent, boron/titanium/zirconium-based crosslinkor, or melamine formaldehyde. The sealing layer further comprises filler comprising carbon black, graphene, graphite, and carbon nanotubes. The sealing layer further comprises a wetting agent, the wetting agent being an organosilicone surface tension reducing agent. The polyurethane is an ester polyurethane and/or a polycarbonate polyurethane. USE - The sealing layer is useful: in electrophoretic display (claimed); and for sealing microcells of electro-optic devices, e.g. liquid crystal display, organic electroluminescence display, or plasma display. ADVANTAGE - The sealing layer: has volume resistivity of 5x 107-1010Ohm.cm; has excellent sealing property; has excellent optical properties e.g. optical transmission, reflectance, luminescence or pseudo-color in the sense of change in reflectance of electromagnetic radiation; utilizes poly(vinylalcohol) polymer or the poly(vinylalcohol-co-ethylene) copolymer which has a degree of hydrolysis of 92-99%; improves sealing stability; and is economical. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for an electrophoretic display comprising the sealing layer. DESCRIPTION OF DRAWING(S) - The figure shows an electro-optic device comprising a microcell structure. 210Electrode layer 220Microcell layer 230Sealing layer 240Adhesive layer 250Second electrode layer