Patent ID: 7429688
Filing Date: 2008-09-30
Classification: A61F,Y10T

Abstract:
1. A disposable diaper comprising a liquid-pervious topsheet facing a wearer's body, a liquid-impervious backsheet facing away from the wearer's body and a liquid-absorbent core interposed between said top- and backsheets so as to define a front waist region, a rear waist region and a crotch region extending between said waist regions wherein at least one of said front and rear waist regions and said crotch region is provided with an indicator by which it is perceptible from outside said backsheet whether urination has occurred or not, said disposable diaper further comprising; said indicator being composed of an intermediate sheet comprising a hydrophobic fibrous nonwoven fabric, wherein the nonwoven fabric has a coating thereon comprising a surfactant that hydrophilically modifies said intermediate sheet upon application to the intermediate sheet, and a water-soluble coloring agent depicting a given figure in color different from those of said backsheet and said intermediate sheet; said figure being visible from outside said backsheet, wherein said intermediate sheet is interposed between said backsheet and said core and said coloring agent is applied on at least one of opposed surfaces of said backsheet and said intermediate sheet which are opposed to each other; and urine discharged on said diaper dissolves said surfactant and said coloring agent, said surfactant and said coloring agent dissolved by said urine permeating said intermediate sheet and being absorbed by said core, whereupon said figure substantially disappears and said intermediate sheet restores its initial hydrophobic property so as to prevent said coloring agent once absorbed by said core from flowing back toward said backsheet.