US3920016A

US3920016A - Fastening tab means for a disposable diaper

Info

Publication number: US3920016A
Application number: US503013A
Authority: US
Inventors: Frederick K Mesek; Ludwig Tritsch
Original assignee: Johnson and Johnson
Current assignee: Johnson and Johnson
Priority date: 1974-09-03
Filing date: 1974-09-03
Publication date: 1975-11-18
Anticipated expiration: 1992-11-18

Abstract

A disposable diaper having a moisture-impermeable backing sheet and an absorbent pad suspended on the backing sheet is provided with a fastening tab means attached at one end to the backing sheet near one edge of the diaper. A terminal free portion of the fastening tab means extends inwardly from the diaper edge and lies substantially flat against the inside surface of the diaper, and an intermediate portion of the fastening tab means is doubled over on itself to form a relatively small section having two tab thicknesses outside the perimetric limits of the diaper.

Description

United States Patent 1191 Mesek et al.

1 FASTENING TAB MEANS FOR A DISPOSABLE DIAPER [75] Inventors: Frederick K. Mesek, Downers Grove; Ludwig Tritsch, Wilmette, both of I11.

[73] Assignee: Johnson & Johnson, New

Brunswick, NJ.

[22] Filed: Sept. 3, 1974 [2]] Appl. No.: 503,013

. [52] US. Cl 128/287; 128/284 [51] Int. Cl. A61F 13/16 [58] Field of Search 128/284, 287, 290 R, 286

[56] References Cited UNITED STATES PATENTS 2,714,889 8/1955 Chambers 128/287 3,750,669 8/1973 DeLuca 128/287 3,776,234 12/1973 Hoey 128/287 Nov. 18, 1975 3,794,038 2/1974 Buell 128/287 3,810,472 5/1974 Aldinger 128/287 3,848,594 11/1914 B11811 128/284 3,848,596 11/1974 Pennau 128/284 Primary Examiner-Aldrich F. Medbery [57] ABS 10 Claims, 5 Drawing Figures U.S. Patent Nov. 18, 1975 3,920,016

FIG. 4

FIG. 5

FASTENING TAB MEANS FOR A DISPOSABLE DIAPER BACKGROUND OF THE INVENTION This invention relates to diapers. More particularly, this invention relates to diapers which are adapted to be used once and then discarded.

Disposable diapers provide substantial advantages in convenience over conventional diapers and commonly have a generally quadrilateral configuration with straight or curvilinear longitudinal edges. Recently, disposable diapers have been secured about an infant by means of adhesive tape tabs which are affixed to the diaper along a longitudinal edge thereof, thus eliminating the need for extraneous fasteners, such as pins. However, such tabs usually project above and/or beyond the confines of the diaper to a considerable extent and interfere with the efficient manufacture, folding and packing of the diaper. I

U.S. Pat. No. 3,776,234 to Hoey proposes to fold the tab over on itself at the diapers edge and to adhesively attach a portion of the folded-over tab segment to theinside surface-of the diaper in order to keep the tab from interfering with manufacturing machinery and with the folding and packaging operation. This requires .that the backing sheet of the diaper be folded over to be present at the front face or inside of the diaper, and a relatively involved tab design is provided which complicates manufacturing manipulation. Also, undesirable tearing of the diaper facing fabric may result if such a tab is adhesively attached to the facing fabric of the diaper. U.S. Pat. No. 3,646,937 to Gellert shows a fastening tab provided with a release surface which is permanently bonded to the inside surface of the diaper; however, such an arrangement is disadvantageous because the release surface may be placed in contact with the infants skin when the diaper is used.

SUMMARY OF THE INVENTION The present invention contemplates a disposable diaper of substantially quadrilateral configuration, i.e., rectangular or contoured configuration, having an inside surface for direction toward an infant and an outside surface for direction away from the infant. The disposable diaper comprises a thin, flexible backing sheet of substantially moisture impermeable material, a moisture-retaining layer including a pad of highly absorbent material superposed on said backing sheet and attached thereto, and a fastening tab means at opposite sides of the diaper having a first tab portion attached to the backing sheet near a longitudinal edge of the diaper. A porous facing layer substantially coextensive with the backing sheet can also be provided as part of the moisture-retaining layer. Each tab means includes a second tab portion adjoining the first tab segment and doubled over on itself so as to form a relatively small folded section outside the perimetric limits of the diaper. Each tab means further includes third tab portion having a pressure sensitive adhesive surface for attachment to the outside surface of the diaper when the diaper is applied to the infant which third tab portion adjoins the second tab segment and lies substantially flat against the inside surface of the diaper. Prior to use the adhesive surface on the third tab portion bears a release sheet which is readily removable upon use.

BRIEF DESCRIPTION OF THE DRAWING In the drawing,

FIG. 1 is a perspective view showing a diaper of this invention in the form normally assumed during use;

FIG. 2 is a plan view of the diaper shown in FIG. 1;

FIG. 3 is a fragmentary sectional view taken along plane 3-3 in FIG. 2 and enlarged to show interior detail;

FIG. 4 is a similar fragmentary sectional view showing a further embodiment of the present invention; and

FIG. 5 is a fragmentary sectional view showing another embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, disposable diaper 10 is shown in a form usually assumed when applied to an infant. Inside surface 11 is directed toward the infant and outside surface 12 is directed away from the infant. Fastener tab means 13 and 14 are located near

longitudinal edges

15 and 16, respectively, and adjacent to respective top corners 17 and 18 (FIG. 2). As diaper 10 is applied to the torso of an infant, it assumes the configuration shown in FIG. 1, and top corners l7 and 18

overlap bottom corners

19 and 20. As shown in FIGS. 2 and 3, diaper 10 is made up of thin, flexible backing sheet 21 which is substantially moisture-impermeable. A suitable backing sheet can be made of an opaque polyethylene web about 0.001 inch thick. Another suitable flexible sheet material is a polyethylene terephthalate web about 0.0005 inch thick. Centrally disposed, highly absorbent pad 47 is part of moistureretaining layer 22 which is superposed on backing sheet 21 and attached thereto in any convenient manner, e.g., by adhesive attachment or the like. If desired, an additional layer of a non-woven fabric of the type shown in U.S. Pat. No. 3,730,184 to Mesek can be applied over absorbent pad 47 as part of moisture-retaining layer 22. Another diaper construction eminently suitable for practicing the present invention is shown in U.S. Pat. No. 3,683,916 to Mesek et al. Still other suitable disposable diaper structures are shown in U.S. Pat. No. 3,612,055 to Mesek et al. which teaches the use of a porous facing layer over a moisture-retaining layer or layers, and in U.S. Pat. No. Re. 26,151 to Duncan et al.

The fastening tab means in accordance with the present invention can be made from polyethylene tape stock, polypropylene tape stock, or the like, as illustrated in FIGS. 3, 4 and 5. As shown in FIG. 3, fastening tab 13 comprises a first tab portion 23 which is attached by means of adhesive layer 24 to backing sheet 21 near a longitudinal edge of the diaper. Second tab portion 25 adjoins first tab segment 23 and is doubled over on itself so as to form a relatively small section of two tab thicknesses which are adhesively attached to each other by means of adhesive layer 24. Second tab portion 25 is considerably smaller than first tab portion 23 and extends beyond the perimetric limits of diaper l0 usually about 0.125 inch. Third tab portion 26 adjoins second tab portion 25 and extends inwardly over the inside surface of the diaper. The dimensions of second tab portion 25 are selected so as to maintain third tab portion 26 in a substantially flat overlying position relative to the inside surface of the diaper. In order to prevent adhesion of third tab portion 26 to the inside surface of the diaper, release sheet 27 is provided covering that portion of adhesive layer 24 which is coextensive with tab portion 26. Advantageously release sheet 27 can be provided with free end 28 which is folded back against release sheet 27 and provides a convenient grip means for pulling release sheet 27 away from the adhesive surface when the diaper is prepared for use. The release sheet can be made of a wide variety of non-tacky materials, e.g., silicone-coated paper strip, smooth non-adherent plastic strip, such as polyethylene or polypropylene sheet, treated with silicone rubber or the like, which is readily removable from pressure sensitive adhesive surface 24 when the diaper is to be secured about an infant.

The adhesive-to-adhesive contact of the doubledover parts of portion 25 provides a substantially permanent fold or pleat. In the event it is desired to provide a lesser degree of adhesion between the doubled-over parts so that the formed fold or pleat can be removed from tab 13 when the diaper is prepared for use, adhesive layer 24 can be made less tacky in the region of segment 25 by applying a powder such as talc over the surface of adhesive layer 24, in an amount which renders the surface releasably tacky.

In the embodiment illustrated in FIG. 4, flexible backing sheet 29 and moisture-retaining layer 30 superposed thereon comprises a diaper provided with fastening tab 31. First tab portion 32 is secured to backing sheet 29 by adhesive layer 33. Second tab portion 34 is doubled over on itself to form a fold and third tab portion 35 adjoins segment 34. Adhesive layer 33 is coextensive with tab 31. Release sheet 36 covers the adhesive surface of third tab portion 35 and has one end .37 extending into the fold formed by the doubled-over parts of portion 34 so that the juxtaposed adhesive surfaces on portion 34 are adhesively attached to end 37 of release sheet 36. End 37, of course, is provided with suitable release surfaces on both sides so that it is readily released from adhesive layer 33 when tab 31 is used. Release sheet 36 also extends beyond tab segment 35 so as to provide free end 38 which serves as a grip means for removing the release sheet so as to uncover the adhesive surfaces on

tab portions

34 and 35. In a further variant of this embodiment, end 37 can be provided with a release coating on only one side thereof and severed from or severably attached to the main portion of release sheet 36 so that end 37 is retained on adhesive layer 33 as a separate release material segment when the rest of release sheet 36 is removed preparatory to placing the diaper in use. If greater holding strength is desired for keeping the tab portion 34 in the doubled-over configuration, end 37 of release sheet 36 can be perforated to provide limited adhesive-to-adhesive contact for doubled-over portion 34.

Where both the flexible backing sheet and the fastening tab are made of a thermoplastic material which can be readily fused, the fastening tab can be bonded directly to the backing sheet of the diaper. Also, the doubled-over tab portion which extends beyond the perimetric limits of the diaper can be lightly heat-bonded or tack-bonded together to releasably maintain the doubled-over configuration until such time when the diaper is used. Alternatively, the doubled-over tab portion can be permanently fused together without the need for an auxiliary adhesive. This is illustrated in FIG. wherein thermoplastic backing sheet 39 is provided with fastening tab 40 having first tab portion 41 fused to backing sheet 39. Second tab portion 42 is folded over on itself and the resulting juxtaposed thicknesses are fused together by suitable application of heat. Third tab portion 43 which adjoins tab portion 42 is provided with adhesive layer 44 which is covered with release sheet 45. Free end 48 of release sheet 45 is folded back in a manner similar to that shown in FIG. 3. Free end 48 abuts the edge of moisture-retaining layers 46 superposed on backing sheet 39 without interfering with the generally flat position of tab portion 43 which overlies the inside surface of moisture-retaining layer 46 free of attachment to the diaper.

Suitable pressure-sensitive adhesives for the present purposes are known in the art and possess good tack, good cohesive strength, good moisture resistance and good resistance to aging. Illustrative of such adhesive compositions are mixtures of natural or synthetic rubber with zinc oxide and various resins, natural or synthetic rubber or resin latices, tacky acrylic polymers or copolymers, and the like.

In use, a disposable diaper equipped with the fastening tab means of this invention is applied to the infant by laying out the diaper on a suitable flat surface and placing the infant thereon so that the waist-underlying end of the diaper is that having the fastener tab. The other end of the diaper then extends downwardly between the infants legs. Next, the downwardly extending end of the diaper is brought up between the infants legs to a position contiguous to the front of the infants waist. The diaper is thereafter secured to the infant by placing the corners of the waist portion of the abdomen-covering end as far around the infants waist as they will go and by bringing the corners of the underlying end of the diaper into an overlapping relationship with the aforementioned corners so that the diaper snugly encircles the infants waist. The release sheets are then lifted from the adhesive surfaces provided on the third tab segment of each fastening tab and the corners of the underlying end of the diaper are fixed in the aforesaid overlapping position by simply urging the pressure sensitive adhesive surfaces on each fastening tab in contact with the outside surface of the underlying diaper backing sheet thus custom fitting the diaper about the infant.

The foregoing description and the drawing are illustrative but are not to be taken as limiting. Still other variations and modifications are possible without departing from the spirit and scope of this invention.

We claim:

1. A disposable diaper of substantially quadrilateral configuration defined by longitudinal and transverse peripheral edges and having an inside surface for direction toward an infant when the diaper is worn by that infant and an outside surface for direction away from said infant, which disposable diaper comprises a thin flexible backing sheet of substantially moistureimpermeable material; a moisture-retaining layer including a pad of absorbent material superposed on said backing sheet and attached thereto; and a fastening tab means having a first tab portion attached to a portion of said backing sheet superposed by said moisture-retaining layer and near a longitudinal edge of said diaper, a doubled over second tab portion adjoining the first tab portion and attached to itself and forming a relatively small folded section outside the perimetric limits of the diaper, and a third tab portion adjoining the second tab segment, extending over to lie substantially flat against said diaper inside surface but free from attachment thereto, and having a pressure sensitive adhesive surface for attachment to the outside surface of the diaper when the diaper is applied to the infant.

2. The disposable diaper in accordance with claim 1 wherein the doubled-over portions of said second tab segment are adhesively attached to each other.

3. The disposable diaper in accordance with claim 2 wherein said second tab segment is provided with a pressure sensitive adhesive having a releasably tacky surface and wherein the doubled-over portions are adhesively but releasably attached to each other.

4. The disposable diaper in accordance with claim 1 wherein said second tab segment is provided with a pressure sensitive adhesive layer on juxtaposed surfaces of the second tab segment and said juxtaposed surfaces are adhesively attached to opposite sides of a terminal portion of a strip of release sheet interposed therebetween, and wherein said terminal portion is perforated and is severable from the remainder of said strip of release sheet.

5. The disposable diaper in accordance with claim 3 wherein said strip of release sheet additionally covers the adhesive surface on said third tab segment and is provided with a free end extending beyond said third tab segment.

6. The disposable diaper in accordance with claim 1 wherein said backing sheet and said fastening tab means both are made of a thermoplastic material, wherein said first tab segment is fused to said backing 6 sheet, and wherein the doubled-over portions of said second tab segment are releasably bonded to each other.

7. The disposable diaper in accordance with claim 1 wherein the adhesive surface on said third tab segment is covered by a release sheet.

8. The disposable diaper in accordance with claim 7 wherein said release sheet is provided with a free end near the juncture of said second tab segment and said third tab segment and wherein said free end is folded back against said release sheet.

9. The disposable diaper in accordance with claim 1 wherein said second tab segment is provided with a pressure sensitive adhesive layer on juxtaposed surfaces thereof, wherein a release material segment is interposed between said juxtaposed surfaces, and wherein a strip of release sheet covers the adhesive surface on said third tab segment.

10. The disposable diaper in accordance with claim 1 wherein said backing sheet and said fastening tab means both are made of a thermoplastic material, wherein said first tab segment is fused to said backing sheet, and wherein the doubled-over portions of said second tab segment are releasably bonded to each other.

UNITED STATES PATENT AND TRADEMARK OFFICE QETIFICATE OF CORRECTION PATENT NO. 3,920,016 DATED November 18,1975 INVENTCWS) Frederick K. Mesek and Ludwig Tritsch 'ed first en's-r HDDSZHS in fhe ubove-edenhfied pateni and that said Letters Patent .1 T slmw imgw' In the Abstract, line 2, "suspended" should read superposed In Column 1, line 21, "packing" should read packaging should read In Column 1, line 58, "segment" portion In Column 1, line 65, "segment" should read portion In Column 2, should read line 5h, "segment" portion should read In Column 3, line 29,

"segment" portion Signed and Scaled this thirtieth D f March 1976 [SEAL] A ttes t:

C. MARSHALL DANN Commissioner ofPaIenIs and Trademarks RUTH C. MASON Alresling Officer

Claims

1. A disposable diaper of substantially quadrilateral configuration defined by longitudinal and transverse peripheral edges and having an inside surface for direction toward an infant when the diaper is worn by that infant and an outside surface for direction away from said infant, which disposable diaper comprises a thin flexible backing sheet of substantially moisture-impermeable material; a moisture-retaining layer including a pad of absorbent material superposed on said backing sheet and attached thereto; and a fastening tab means having a first tab portion attached to a portion of said backing sheet superposed by said moisture-retaining layer and near a longitudinal edge of said diaper, a doubled over second tab portion adjoining the first tab portion and attached to itself and forming a relatively small folded section outside the perimetric limits of the diaper, and a third tab portion adjoining the second tab segment, extending over to lie substantially flat against said diaper inside surface but free from attachment thereto, and having a pressure sensitive adhesive surface for attachment to the outside surface of the diaper when the diaper is applied to the infant.

6. The disposable diaper in accordance with claim 1 wherein said backing sheet and said fastening tab means both are made of a thermoplastic material, wherein said first tab segment is fused to said backing sheet, and wherein the doubled-over portions of said second tab segment are releasably bonded to each other.