Production method of elastic composite sheet, elastic composite sheet, and disposable wearable article using said elastic composite sheet

Patent metadata

Field	Value
Publication number	US-2020360191-A1
Application number	US-201816965114-A
Country	US
Kind code	A1
Filing date	Dec 17, 2018
Priority date	Jan 31, 2018
Publication date	Nov 19, 2020
Grant date	—

Abstract

In a production method of an elastic composite sheet, the elastic member does not break when the elastic member, in a stretched state, is bonded to a base material sheet; an elastic composite sheet and a disposable wearable article use the elastic composite sheet. A strip-shaped or string-shaped elastic member composed mainly of a thermoplastic elastic resin is stretched in the longitudinal direction of the elastic member. The stretched elastic member is placed over a first base material sheet such that the main surface of the first base material sheet contacts the elastic member. In this state, the elastic member and the first base material sheet are bonded in a first position that overlaps the elastic member seen from a direction perpendicular to the main surface of the first base material sheet and that is away from the edges of the elastic member.

First claim

1 . A method for producing an elastic composite sheet, comprising:
a first step of stretching a strip-shaped or string-shaped elastic member in a longitudinal direction of the elastic member, the elastic member being composed mainly of a thermoplastic elastic resin; a second step of placing the stretched elastic member over a first base material sheet in a manner that a main surface of the first base material sheet comes into contact with the elastic member; and a third step of, with the stretched elastic member placed over the first base material sheet, bonding the elastic member to the first base material sheet at a first location overlapping the elastic member and located away from edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

2 . The method for producing the elastic composite sheet according to claim 1 , wherein
the elastic member is provided by extruding a heated and molten elastic resin material in a form of a strip, the elastic resin material being composed mainly of the thermoplastic elastic resin.

3 . The method for producing the elastic composite sheet according to claim 1 , wherein
the second step involves placing a second base material sheet over the elastic member and the first base material sheet in a manner that the elastic member is sandwiched between the first base material sheet and the second base material sheet, and the third step involves bonding the second base material sheet to at least either one of the elastic member and the first base material sheet.

4 . The method for producing the elastic composite sheet according to claim 1 , wherein
the first step involves disposing a plurality of the elastic members spaced from each other and stretching each of the elastic members in the longitudinal direction, and the second step involves placing the stretched elastic members over the first base material sheet.

5 . The method for producing the elastic composite sheet according to claim 1 , wherein
the third step involves bonding the elastic member to the first base material sheet at intervals in a direction of extension of the elastic member.

6 . The method for producing the elastic composite sheet according to claim 3 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at a second location located away from the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

7 . The method for producing the elastic composite sheet according to claim 3 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at a third location adjacent to an associated one of the edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

8 . The method for producing the elastic composite sheet according to claim 3 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at pairs of third locations, the third locations in each pair facing each other and each being adjacent to an associated one of the edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

9 . The method for producing the elastic composite sheet according to claim 1 , wherein
for bonding in the third step, ultrasonic bonding is used.

10 . An elastic composite sheet comprising:
a base material sheet; and a strip-shaped or string-shaped elastic member composed mainly of a thermoplastic elastic resin and bonded to the base material sheet in a manner that the elastic member is in contact with a main surface of the base material sheet, wherein with the elastic member stretched in a longitudinal direction of the elastic member, the elastic member is bonded, at intervals in a direction of extension of the elastic member, to the base material sheet at a plurality of locations overlapping the elastic member and located away from edges of the elastic member as viewed in a direction perpendicular to the main surface of the base material sheet.

11 . A disposable wearable article comprising:
a front waist portion; a rear waist portion spaced from and facing the front waist portion; and a crotch portion connected to the front waist portion and the rear waist portion, wherein one or both of the front waist portion and the rear waist portion includes or include the elastic composite sheet according to claim 10 , and the elastic composite sheet is disposed in a manner that the elastic member extends in a direction around a waist of the disposable wearable article.

12 . The method for producing the elastic composite sheet according to claim 2 , wherein
the second step involves placing a second base material sheet over the elastic member and the first base material sheet in a manner that the elastic member is sandwiched between the first base material sheet and the second base material sheet, and the third step involves bonding the second base material sheet to at least either one of the elastic member and the first base material sheet.

13 . The method for producing the elastic composite sheet according to claim 2 , wherein
the first step involves disposing a plurality of the elastic members spaced from each other and stretching each of the elastic members in the longitudinal direction, and the second step involves placing the stretched elastic members over the first base material sheet.

14 . The method for producing the elastic composite sheet according to claim 2 , wherein
the third step involves bonding the elastic member to the first base material sheet at intervals in a direction of extension of the elastic member.

15 . The method for producing the elastic composite sheet according to claim 12 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at a second location located away from the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

16 . The method for producing the elastic composite sheet according to claim 6 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at a third location adjacent to an associated one of the edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

17 . The method for producing the elastic composite sheet according to claim 12 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at a third location adjacent to an associated one of the edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

18 . The method for producing the elastic composite sheet according to claim 6 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at pairs of third locations, the third locations in each pair facing each other and each being adjacent to an associated one of the edges of the elastic member as viewed in a direction perpendicular to the main surface of the first base material sheet.

19 . The method for producing the elastic composite sheet according to claim 12 , wherein
the third step involves bonding the first base material sheet to the second base material sheet at pairs of third locations, the third locations in each

Assignees

• Zuiko Corp

Inventors

• Nakamura Hideyuki
• Fujita Yukihiko
• Kita Ayako

Classifications

• B32B2555/02

  Diapers or napkins · CPC title

• B32B37/144

  using layers with different mechanical or chemical conditions or properties, e.g. layers with different thermal shrinkage, layers under tension during bonding (constructional features for tensioning B32B38/1825) · CPC title

• B32B37/04

  characterised by the partial melting of at least one layer · CPC title

• B32B37/0084 Primary

  Point bonding · CPC title

• B29L2031/4878

  Diapers, napkins · CPC title