Patents

Disposable Diaper:

March 27, 2017

U.S. Patent No. 9,566,199

Satoru Sakaguchi, Kanonji, Japan.
Assigned to Unicharm Corporation, Ehime, Japan.

Filed: 3/28/13
Issued: 2/14/17

A disposable diaper, comprising: a vertically long absorbent body formed by a front waistline unit, a back waistline unit, and a crotch unit, and including a liquid-retentive absorber; side flaps provided at least at a part of side edges of the absorbent body in a product widthwise direction of the disposable diaper; and a fastening tape attached to one of the side flaps, extending outwardly in the product widthwise direction from one of the front waistline unit and the back waistline unit, and configured to be fastened to a remaining one of the front waistline unit and the back waistline unit; wherein the fastening tape has a base sheet, and a hook sheet provided with a plurality of engagement hooks and fixed on a surface of the base sheet, the fastening tape has a tip region not provided with the hook sheet, and a hook sheet region provided with the hook sheet and inwardly adjacent to the tip region in the product widthwise direction, an engagement strength of the fastening tape is 0.3 N/30 mm or more, and 1.5 N/30 mm or less, a density of the engagement hooks is more than 1800 pins/inch, the base sheet is formed of a first nonwoven fabric layer configured to face toward a wearer’s garment and a second nonwoven fabric layer configured to face toward the wearer’s skin, a thickness of the first nonwoven fabric layer is less than a thickness of the second nonwoven fabric layer, the fastening tape has (i) a first bending rigidity value when the fastening tape is bent in a first direction from the hook sheet toward the base sheet to form a central apex closer to a wearer’s garment than edges of the fastening tape, and (ii) a second bending rigidity value when the fastening tape is bent in a second direction from the base sheet toward the hook sheet to form a central apex closer to the wearer’s skin than the edges of the fastening tape, and the first bending rigidity value of the fastening tape is greater than the second bending rigidity value of the fastening tape.