WATERPROOF SHEET OR EXTENSION SHEET, ITS DEFECT DETECTING METHOD, AND DEFECT DETECTING METHOD FOR JOINT BETWEEN WATERPROOF SHEET AND EXTENSION SHEET

摘要

PROBLEM TO BE SOLVED: To provide an extension sheet allowing easy detection of a defective portion of a waterproof sheet or extension sheet itself and ensuring easy detection of a poor joint portion. ;SOLUTION: A waterproof sheet A or an extension sheet B is formed of thermoplastic resin or synthetic rubber and constructed with a surface layer 1 and a back layer 2, the surface layer being colored and non-transparent and the back layer containing luminescent material. An extension sheet C to be joined to the water-proof sheet A or a usual water-proof sheet D has a luminescent material containing transparent layer at the peripheral edge 3 and a colored and non-transparent surface layer and a luminescent material containing back layer at other portions. A defective portion 4 of the sheet itself is observed with a leaking light and a defective portion (poor joint portion) 6 of a joint between the water-proof sheet and the extension sheet is observed with a difference in reflected light in detecting work.;COPYRIGHT: (C)2001,JPO