NOVELTY - Photocurable composition comprises photocurable monomer and hydroxy group containing monomer (I).    USE - The composition is useful for forming organic barrier layer of encapsulated devices, preferably flexible organic light emitting device, organic light emitting device (both preferred), lighting devices, metal sensor pads, micro-disk lasers, electrochromic device, photochromic device, microelectromechanical systems, solar cells, integrated circuit, charge-coupled device and polymeric luminescent body, light emitting diodes (all claimed).    ADVANTAGE - The composition exhibits high curing rate and does not generate shift due to the post-cure hardening contraction stress.    DETAILED DESCRIPTION - Photocurable composition comprises photocurable monomer and hydroxy group containing monomer of formula (I).    R1 = 1-20C alkylene, 6-20C arylene or 5-20C cycloalkylene (all optionally substituted);    R2 = 1-10 alkylene (optionally substituted and optionally containing -O-, -S- or -NR- in the molecular chain);    R = H, 1-10C alkyl or 6-20C aryl;    X1, X2 = 1-20C alkyl, 6-20C aryl, 5-20C cycloalkyl (all optionally substituted), H or OH, where at least one of X1 and X2 is OH;    Z1, Z2 = H or acryloyl containing groups of formula (II), (III) or (IV), where at least one of Z1 and Z2 is (II), (III) or (IV);    R4, R5 = 1-10C alkylene or 6-20C arylene;    R6 = H or 1-10C alkyl (optionally substituted); and    n = 0-20.    An INDEPENDENT CLAIM is also included for an encapsulated device comprising a device component (20) and barrier stack (30) comprising inorganic barrier layer (31) and organic barrier layer (32), formed on the device component, where adhesion strength of the organic barrier layer with the inorganic barrier layer is 7-50 kg-force/mm2.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic cross-sectional view of encapsulated device.    Substrate (10)    Device component (20)    Barrier stack (30)    Inorganic barrier layer (31)    Organic barrier layer (32)