To provide water-resistant paperboard which retains a water-repelling effect, has excellent dimensional stability and printing suitability, and can be recycled, and to provide a method for producing the same.
This paperboard having a middle layer between a front layer and a back layer is characterized by adding a water-repelling agent to the front layer and/or the back layer in an amount of 0.5 to 1.8 mass% based on a pulp solid content. The middle layer preferably contains a wet paper-strengthening agent. When the content of a wax is ≤1.5 mass%, the paperboard can easily be recycled. The water-resistant paperboard is produced by adding a water-repelling agent to a paper material for the front layer and/or a paper material for the back layer and then forming the paperboard together with a paper material for the middle layer.
MIZOBUCHI HIROSHI
YAMAMOTO TADASHI
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