| 摘要 |
PROBLEM TO BE SOLVED: To provide a bulletin board which has sufficient water resistance even for outdoor use and is recoverable as waste paper after use by laminating easily and hardly degradable, moistureproof and waterproof paper on both surfaces of a paper sheet having on edge wick (wet permeation distance) of a specific value or below, thereby constituting the bulletin board. SOLUTION: This bulletin board is constituted by laminating the easily and hardly degradable, moistureproof and waterproof paper on both surfaces of the paper sheet having an edge wick of <=6 mm/24 hr. More particularly the component material is required to be formed and selected in such a manner that the wedge wick as the important index for water resistance attains 6 mm/24 hr. If the wedge wick exceeds 6 mm/24 hr, the penetration of rain water from the cutting surfaces occurs during the exposure to rain and there is a possibility of the occurrence of daytime peeling and shape collapse when the bulletin board is used outdoors. The easily and hardly degradable, moistureproof and waterproof paper is exemplified by the easily and hardly degradable, moistureproof and waterproof paper provided with moistureproof layers consisting essentially of water-soluble resins or water-dispersible resins by coating raw paper as the stock to be adequately used.
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