Abstract: A sealing material which comprises (A) an unsaturated group-containing ester-type urethane oligomer which is an energy ray-curable liquid resin and (B) a compound having at least one carbodiimide group in the molecule in an amount of 0.01 to 10 parts by mass based on 100 parts by mass of the component (A) and which is excellent in moist heat durability, can retain low moisture permeability, is excellent in adhesion to a material to be jointed and can form a highly precise extrusion shape; a process for production of a scaling material excellent in long-term storage stability; a scaling material produced by the process; a gasket using a sealing material having the above-mentioned properties. A cured product of the sealing material has a reduced surface adhesion property, enables the easy removal of an HDD cover, and consequently is improved in durability against an external force produced at the time of reuse.

Abstract: The invention relates to a process for producing a gasket for hard disc equipment which is integrated with a cover member by extruding a gasket material from an extrusion orifice of a three-dimensional automatic coating controlling apparatus onto the cover member and then curing the extruded gasket material, wherein a ratio (h/w) of a height (h) of the gasket to a line width (w) of the gasket on a joint surface between the gasket and the cover member is in the range of 0.8 to 3.0 in a 80% or more portion of the gasket.