US Patent 7481246 Lateral pipe lining material and lateral pipe lining method

A lateral pipe lining material comprises a tubular resin-absorbing material impregnated with a curable resin and a brim attached at one end thereof. The lining material is positioned so that the brim faces a peripheral edge of a lateral pipe opening of the main pipe. A ring-shaped gasket composed of an elastic material is attached to an upper surface of the brim, and a bonding resin is applied thereto. The gasket seals a gap between an inner peripheral surface of the main pipe and the brim. The lateral pipe lining material is evertedly inserted into the lateral pipe in a state in which the bonding resin applied to the brim is brought into contact with the inner peripheral surface of the main pipe. In such a configuration, ground water can be prevented from seeping into the bonding resin applied to the brim even if the ground water flows into the main pipe from a break of the lateral pipe.