Method for making disposable diapers

• US 5,507,895 A
• Filed: 05/16/1994
• Issued: 04/16/1996
• Est. Priority Date: 05/19/1993
• Status: Expired due to Term

• Current Assignee: Unicharm Corporation
• Original Assignee: Unicharm Corporation
• Inventors: Suekane, Makoto
• Primary Examiner(s): AFTERGUT, JEFFRY H
• Application Number:
  US08/242,976
• Time in Patent Office: 701 Days
• Field of Search: 156/73.1, 156/73.4, 156/163, 156/164, 156/308.4, 156/323, 156/324.4, 156/292, 156/227, 156/217, 156/204, 604/358, 604/366, 604/370, 604/385.1, 2/400
• US Class Current: 156/73.1
• CPC Class Codes: A61F 13/15739 Sealing, e.g. involving cutting
• CPC Class Codes: A61F 13/4942 the barrier not being integral with the top- or back-sheet
• CPC Class Codes: A61F 13/496 in the form of pants or briefs
• CPC Class Codes: A61F 13/4963 characterized by the seam
• CPC Class Codes: A61F 13/513 characterised by its function or properties, e.g. stretchability, breathability, rewet, visual effect; having areas of different permeability
• CPC Class Codes: A61F 13/515 characterised by the interconnection of the topsheet and the backsheet
• CPC Class Codes: A61F 13/531 having a homogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence
• CPC Class Codes: A61F 2013/15869 with ultrasonic energy
• CPC Class Codes: A61F 2013/51409 being a film
• CPC Class Codes: B29C 65/08 using ultrasonic vibrations non-plastics element to plastics elements B29C65/645
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/133 Fin-type joints, the parts to be joined being flexible the parts to be joined being rigid B29C66/1312
• CPC Class Codes: B29C 66/21 said joint lines being formed by a single dot or dash or by several dots or dashes, i.e. spot joining or spot welding
• CPC Class Codes: B29C 66/431 Joining the articles to themselves B29C66/4322 and B29C66/4332 take precedence
• CPC Class Codes: B29C 66/433 Casing-in, i.e. enclosing an element between two sheets by an outlined seam for bookbinding B42C11/06; for packaging B65B; by laminating B32B37/00; enclosing tubular articles between substantially flat elements B29C66/53261
• CPC Class Codes: B29C 66/81427 comprising a single ridge, e.g. for making a weakening line; comprising a single tooth
• CPC Class Codes: B29K 2023/12 PP, i.e. polypropylene
• CPC Class Codes: B29K 2105/0854 in the form of a non-woven mat
• CPC Class Codes: B29L 2031/4878 Diapers, napkins
• CPC Class Codes: Y10T 156/1015 Folding
• CPC Class Codes: Y10T 156/1036 : Bending of one piece blank and joining edges to form article
• CPC Class Codes: Y10T 156/1051 : by folding

Abstract

To obtain a disposable diaper having at its respective waist sides welded zones which provide smooth touch, herein disclosed a method for making a disposable diaper 1 comprising steps of putting wing-like portions 21, 22 provided on front and rear bodies 5, 6 of the diaper 1 one upon another with a topsheet 2 facing inward, and welding these wing-like portions together under heat and pressure. In each wing-like portion 21, 22, a piece of sheet member is attached to at least one of the top- and backsheets 2, 3 so as to form an extension thereof and provide thereby the backsheet of said portion having a melting point higher than a melting point of the topside sheet member.

Claims

1. A method for making a disposable diaper generally comprising steps of assembling a liquid-permeable topsheet, a liquid-impermeable backsheet and a liquid-absorbent core sandwiched between these sheets into a configuration of disposable diaper, putting wing-like portions of front and rear bodies of the diaper outwardly extending from laterally opposite side edges of said core one upon another and welding said wing-like portions together under heat and pressure to form laterally opposite side portions at waist levels of said front and rear bodies, said method further comprising steps of:

attaching a sheet to at least one of top- and backsheets in each wing-like portion so as to form an extension thereof and provide thereby the backsheet of said portion having a melting point higher than a melting point of the topsheet of said portion, and welding said top- and backsheets together along each waist side of the diaper.

2. The method of claim 1 wherein the topsheet has a melting point higher than that of the backsheet, a sheet which is attached to said topsheet in said wing-like portion having a melting point lower than that of said backsheet.

3. The method of claim 1 wherein the topsheet has a melting point higher than that of the backsheet, a sheet which is attached to said backsheet in said wing-like portion having a melting point higher than that of said topsheet.