NOVELTY - Barrier laminate (I) having at least one organic layer and at least one inorganic layer is claimed, in which the organic layer contains a polymer having a structural unit of substituted ester compound (1a) or (2a).    USE - (I) is useful in: a device for sealing; a barrier film substrate, which is useful as a substrate of the device for sealing, where the device is an electronic device (preferably an organic electroluminescent device); and an optical component (all claimed). (I) is useful in an organic semiconductor device, liquid-crystal display devices, thin-film transistors, touch panels, electronic papers, solar cells and other electronic devices.    ADVANTAGE - (I) is excellent in producibility and has a low water vapor permeability. (I) has excellent barrier property. The organic layer is formed in a simplified method capable of saving time and cost. (I) provides a barrier film substrate of high barrier capability and a device and an optical component of high durability. The method produces (I) in an easy way, saving time and cost, as it does not require any additional equipment such as vacuum equipment and gas pipe equipment.    DETAILED DESCRIPTION - Barrier laminate (I) having at least one organic layer and at least one inorganic layer is claimed, in which the organic layer contains a polymer having a structural unit of substituted ester compound of formula (R1-X1-O-CH2-(-C(CH2)-)-C(=O)-O-R2) (1a) or (R3-O-C(=O)-(-C(CH2)-)-CH2-O-X2-R5-X3-O-CH2(-C(CH2)-)-C(=O)-O-R4) (2a).    R1 = H or hydrocarbon group;    R2-R4 = hydrocarbon group;    R5 = alkylene group which may have an ether group inserted into the chain; and    X1-X3 = single bond or carbonyl group.    INDEPENDENT CLAIMS are included for:    (1) a method for producing (I) having at least one organic layer and at least one inorganic layer, comprising polymerizing a monomer mixture that contains at least one monomer of substituted ester compound of formula (R1-X1-O-CH2-C(=CH2)-C(=O)-O-R2) (3a) or (R3-O-C(=O)-C(=CH2)-CH2-O-X2-R5-X3-O-CH2-C(=CH2)-C(=O)-O-R4) (4a) to form the organic layer;    (2) a barrier film substrate having (I) on at least one surface of a plastic film; and    (3) an optical component having the barrier film substrate, as a substrate of it.