Takayoshi Konishi, Kagawa, Japan; Koichi Yamaki, Kagawa, Japan; and Azusa Matsushima, Kagawa, Japan. Assigned to Unicharm Corporation, Ehime, Japan.

Filed: 2/27/12
Issued: 3/29/16

A water disintegratable leak-proof sheet for an absorbent article comprising a water disintegratable base material layer and a water-insoluble and biodegradable resin layer on the water disintegratable base material layer, wherein the water disintegratable leak-proof sheet has a tearing strength in a planar direction of no greater than 0.15 N/40 mmw in both a first direction and a second direction perpendicular to the first direction as measured in accordance with JIS K 6772:1994 7.5, and the water-insoluble and biodegradable resin layer is formed from polylactic acid, and the water disintegratable base material layer is formed from water disintegratable tissue wherein the water-insoluble and biodegradable resin layer comprises regions of low thickness and regions of high thickness, and the water disintegratable base layer comprises regions of low thickness and regions of high thickness, wherein regions of low thickness in the water-insoluble and biodegradable resin layer correspond to regions of high thickness in the water disintegratable base layer, and regions of high thickness in the water-insoluble and biodegradable resin layer correspond to regions of low thickness in the water disintegratable base layer.