AU596617B2

AU596617B2 - Fluid absorption products

Info

Publication number: AU596617B2
Application number: AU65103/86A
Authority: AU
Inventors: Frank Christopher Williams
Original assignee: Johnson and Johnson
Current assignee: Johnson and Johnson
Priority date: 1985-12-19
Filing date: 1985-12-19
Publication date: 1990-05-10
Anticipated expiration: 2006-11-11
Also published as: AU6510386A

Description

59 6641-7 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 Form COMPLETE SPEC IF ICAT ION

(ORIGINAL)

FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: PH03953 C VI-u 19 December, 1985 Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: .""~Related Art: o 41 Acua Inenor h..ddress fo Applic I' L) TO BE COMPLETED BY APPLICAN4T JOHNSON JOHNSON Lnt: One Johnson Johnson Plaza, New Brunswick. New Jersey FRANK CHRISTOPHER WILLIAMS e: GRIFFITH HASSEL FRAZER 71 YORK STREET SYDNEY NSW 2000 AUSTRAL IA 6* 14 omplete Specification for the invention entitled: "FLUID ABSORPTION PRODUCTS" The following statement is a full description of this invention, including the best method of performing it known to me/us:

K

The present invention relates to fluid absorption products such as absorptive incontinence products, diapers and sanitary napkins or any other product which is intended to conform substantially to the user's body and to be held in place for the purpose of absorbing body fluid discharges.

Conventionally such fluid absorption products have a moisture permeable facing sheet, and an absorbant batt e.g. of cellulosic fibre. Frequently a moisture impermeable backing sheet is provided to prevent leakage and/or to facilitate holding the product in position on the user's body. In some applications such as disposable baby diapers, the product is fabricated to form a unit in which the facing sheet, batt and backing sheet are secured together with adhesive and have adhesive tapes for securing the diaper on an infant.

Particularly in the field of baby diapers attempts have been made to improve the conformability of the diaper shape to the infant and to improve the comfort of the ,0 diaper and resistance to leakage by the application of elasticated strips typically placed along the sides of the crotch region of the diaper so as to provide a degree of sealing around the infant's legs. However, it is considered that it would be desirable to improve still further the degree of comfort obtainable with a high level 4*16 of resistance to leakage around at least part of the peripheral portions of a baby diaper or of any other fluid .1ii absorption product in the field to which the present invention relates.

'30 According to a first aspect of the invention there is r o t, .provided a fluid absorption product comprising an tb. absorbent batt for absorbing discharged body fluids and a resilient, closed, gas-filled barrier member mounted along at least a portion of the periphery of the batt, the barrier member being flexible and adapted to conform substantially to the user's body to facilitate leakage resistance from the batt at the periphery, the product 3777S/MB 2 JBD-93 a; L ii; being adapted when in use to be held by securing means in close conformity with the user's body, whereby the barrier member is pressed towards the user's body in a conforming manner.

The invention may be implemented in many different embodiments, some of which are described hereinafter. One very important embodiment is an incontinence product of elongated form and intended to be used with the elongated sides extending through the crotch region of the user, and the barrier member comprising barrier portions extending along each of the elongated sides at least through the crotch region.

Another important embodiment of the invention is to the case wherein the barrier member extends around the entire periphery of the batt. The peripheral shape could be rectangular or of an hour-glass shape as may be desired.

Advantageously the product could include a facing sheet e.g. of non-woven fabric extending over the batt and trf secured between portions of the barrier member on opposite t...gfO sides of the batt.

o: In some embodiments of the invention it may be o desirable to provide contractible elastic members secured in the product and arranged to extend along the product adjacent to the barrier member or at least a portion thereof so as to co-operate with the barrier member in ,'0 0 o, conforming the product to the user's body and providing a comfortable sealing arrangement and good fit around the user's body.

One specific embodiment of the invention consists in a disposable diaper comprising a moisture permeable facing t,,c sheet, a moisture impermeable backing sheet and a fibrous f« absorbent batt secured between the facing sheet and the backing sheet and including a resilient, closed, gas-filled barrier member extending along at least part of the peripheral regions of the diaper and adjacent to peripheral portions of the batt.

The diaper described in the preceding paragraph preferably has a reduced-width central portion for location in the crotch region of the user and includes contractible 3777S/MB 3 JBD-93 u:iB~ It- I* elastic members extending along the respective sides of the diaper in the crotch region and adjacent respective portions of the gas-filled member.

For the purpose of improving fit, comfort and leakage resistance, a diaper described in either of the preceding paragraphs may have the barrier member in the form of elongated tubular elements provided around the front and rear waistband regions of the diaper.

For some embodiments of the invention it can be very advantagous to form the gas-filled member from plastic sheet material sealed to provide the barrier member of the desired shape and configuration, the plastic sheet material extending between spaced portions of the barrier member thereby providing a support structure and an arrangement for constituting a moisture impermeable backing sheet for the batt.

Further aspects of the invention consist in a method and apparatus for forming fluid absorption products in any of the forms described above.

rct' In a method aspect, thr invention consists in a method of O0 forming a fluid absorption product which comprises supplying V ti, plastic film strip to a forming device and be nd-ing the strip to provide a generally tubular form including a cavity extending along the strip, introducing gas through a probe located within the formed tubular cavity, sealing the edge regions of the strip to close the tubular form along its length, sealing the tubular form at desired locations by securing together opposite walls of the tubular form after they had been pressed together whereby a resilient, closed Sgas-filled barrier member is produced, and securing a fibrous absorbent batt in co-operating juxtaposition with the i .t gas-filled barrier member.

The method described in the previous paragraph may be implemented readily using polyethylene film and air as the pressurising gas, and the tubular form may be achieved by curling the strip about its longitudinal axis generally 3;777S/MB 4 JBD-93 r around a cylindrical support and sealing the tubular form along an overlapped joint, the sealing being by any convenient means such as heat, ultrasonic welding or adhesives. Alternatively, the barrier member may be formed by securing together two strips of plastic film material whereby two seals are established along the sides of the barrier member.

To provide increased comfort, the invention can be used with a laminated barrier member comprising an interior tubular form of plastic film and an exterior layer of fibrous material such as fusible fibre or thermobonded fabric. The method of construction can readily include continuously supplying the outer layer material as a strip laid over the plastic film supplied for formation of the tubular form, the sealing process simultaneously securing in position the fibrous overlay.

A further important inventive arrangement consists in a method for forming the barrier member to have a complex shape such as rectangular, curved or hour-glass shape.

t0O This method comprises forming plastic film into a sleeve-like form having a width when flattened corresponding substantially to the overall width of the product, engaging the sleeve material between co-operating dies providing a cavity arrangement therebetween for 0 ,'25 defining the shape and configuration of the barrier o member, and sealing together the portions of the sleeve which are pressed together at least along lines extending along the boundaries of the barrier member.

a .I For ill.ustrative purposes only, embodiments of the 30 invention will now be described with reference to the accompanying drawings of which:- Figure 1 schematically illustrates an absorbent product embodying the invention; Figure 2 is a plan view illustrating an embodiment of support barrier; Figure 3 illustrates a diposable diaper in a stretched out condition and with its usual facing sheet 3777 S/MB 5 JBD-93 ~r removed to display the parts within the diaper, the diaper being a specific embodiment of the invention; Figure 4 is a schematic side view illustrating a method of manufacturing elongated linear support barriers for use in the embodiments of the invention and suitable for use for example in the embodiment of Figure 1; Figure 5 is a schematic plan view corresponding to Figure 4 but with the sealing units 30 and 29 omitted; Figure 6 is a cross-sectional end elevation of the support barrier produced by the method described with reference to Figures 4 and Figure 7 is a schematic side elevation of a further method embodying the invention and producing support barriers of complex shape such as that illustrated in Figure 2; Figure 8 is a plan view of the arrangement illustrated in Figure 7; Figure 9 is a schematic perspective view illustrating a support barrier shaping operation to be conducted downstream of the arrangement of Figures 7 and 8; Figure 10 is a side view of the arrangement of Figure 9; Figure 11 is a perspective view of the support barrier product of Figures 9 and 10 taken in axial section; and o. Figure 12 is a perspective view of a further embodiment of product similar to that produced by the S arrangement of Figures 9 and 10 but having a profile similar to that shown in Figure 2.

The product of Figure 1 is shown schematically and could be shaped and dimensioned for use as a sanitary napkin, disposable diaper or adult incontinence product.

The product comprises a fibrous absorbent batt 10 of cellulosic material, an air support barrier unit 11 and an outer wrap 12 of tissue paper, non-wovenfabric or the like, the components being secured together by respective 3777S/MB 6 JBD-93 lines of hot-melt adhesive 13 which extend longitudinally of the product.

The air support, barrier 11 is integrally formed from a sheet of polyethylene film which has air-filled sealed side tubes 14 and a central connecting sheet 15 which acts as a moisture impermeable backing to the product and links together the tubes whereby the batt is located between the tubes.

The wrap 12 holds the entire product together and has its edges overlapped and secured by adhesive on the face of the product to be remote from the user's body.

The product need not be parallel sided and could have a complex shape of air support barrier, for example of the shape shown by the air support barrier 11A of Figure 2.

In this embodiment, the air tube 14A is continuous and of hour-glass shape so it may extend around the periphery of a product such as a disposable diaper. The central sheet will conveniently be left to extend across the product but if for any application its removal is desired, it ttO could be simply cut away in a preliminary process step.

o. The disposable diaper 16 of Figure 3 is of hour-glass Sshape and comprises a plastic backing sheet 17, a shaped fibrous absorbent batt 1.8 of smaller dimensions and a moisture permeable facing sheet which is secured to the banking sheet around the periphery of the batt. In the oo drawing the facing sheet has been omitted for clarity. In the central crotch portion 19, the diaper includes respective elongated air tubes 20 at each side and these lie adjacent and partly overlie conventional elastic 4 30 strips 21 which have the function of contracting the diaper around the thighs of the user. Furthermore, these S elastic strip co-operate with the air tubes 20 to provide an enhanced seal in a comfortable manner.

At each end, the diaper has a waistband portion which incorporates further elongated air tubes 22. The diaper is secured on the user in a conventional manner using adhesive tape tabs not shown in the drawing and during 3777S/MB 7 JBD-93 application of these tabs the diaper is pulled firmly around the waist of the user, thereby urging the tubes 22 towards the user's body for sealing purposes.

Refering now to Figures 4 to 6. fabrication of a support barrier 11 as used in Figure 1 is illustrated.

Polyethylene film is supplied from a roll 25 and curled around a longitudinally extending air discharge tube 26 having an air discharge orifice 27 at its downstream free end. The drawing also illustrates an option of laminating a suitable fabric cover over the film; this is supplied from roll 28. The plastic film or film-fabric laminate has an overlap at the upper region as shown in the drawing and longitudinal seals are established by a heat sealing unit 29 or alternativly ultrasonic or adhesive sealing could be provided. Immediately downstream is an end sealing unit 30 having profiled rotary members which engage the structure for forming spaced transverse seals 31.

t As best shown in Figure 5. in this embodiment the machine produces simultaneously two parallel spaced o cylindrical air tubes 14 with an interconnecting central sheet 15, longitudinal seals 32 being provided as indicated in Figure 6. Downstream of the end sealing unit the air tube 14 are rolled inwardly by guides (not 0,0*5 shown) so that the product has the cross-sectional shape shown in Figure 6.

The embodiment of Figures 7 and 8 is suitable for producing a complex shaped air support barrier. In this I embodiment wide plastic film is supplied from a roll 0 006 00 and optionally laminated with a suitable fabric 36. By 0a, .oo the use of a guide wheel 37 and a tapering guide 38 the Splastic film is drawn into a flattened sleeve extending mainly in the vertical direction and is wrapped around an air probe 40. A longitudinal seal adjacent the overlapped edges of the film is provided by a sealing unit 41, on the downstream side of which is provided a guide 42 (shown 3777S/MB 8 JBD-93 schematically in axial section in Figures 7 and 8) which has the function of changing the configuration of the sleeve so as to make it flattened and extend in the general horizontal plane. For this purpose the guide has a multiplicity of inlet apertures 43 connected to a source of pressurised air for urging the sleeve into the desired location.

The air probe 40 terminates near the downstream end of the guide 43 with a multiplicity of air discharge arms 44.

The desired air support barrier is formed by the process illustrated in Figures 9 and 10 which is immediately downstream of the process illustrated in Figures 7 and 8. A profiled upper roller 45 co-operates with a plain lower roller 46 to press the centre region 49 of the flattened sleeve together when one of the circumferentially extending projections 45A is located as S shown. A seal is established conveniently by heat sealing. Further rotation of the rollers 45, 46 coincides 20 with advancement of the continuous product and a transverse seal 47 at the end of each discrete product o segment is achieved by the transvese rib 45B on the roller It will be seen best from Figure 11 that a continuous S.005 web of discrete air support barrier units 11 are formed, each having a continuous tubular periphery 48 and an interconnecting centre sheet-like region 49.

Figure 12 is a sketch showing in perspective another Sembodiment in which an hour-glass profile for the air tube 48 is provided. In this embodiment lines of heat sealing 50 and 51 are provided on the interior and exterior of the Sstructure by use of suitable heating zones on the profiled roller 45, which is shaped to correspond with the desired hour-glass form.

3777S/MB 9 JBD-93 A

Claims

1. A fluid absorption product comprising an absorbent batt for absorbing discharged body fluids and a resilient, closed, gas-filled barrier member mounted along at least a portion of the periphery of the batt, the barrier member being flexible and adapted to conform substantially to the user:s body to facilitate leakage resistance from the batt at the periphery, the product being adapted when in use to be held by securing means in close conformity with the user's body, whereby the barrier member is pressed towards the user's body in a conforming manner.

2. A product as claimed in claim 1 and shaped and dimensioned for use an an incontinence product of elongated form and intended to be used with the elongated sides extending through the crotch region of the user, and Sthe barrier member comprising barrier portions extending along each of the elongated sides at least through the crotch region. 4 4 o

3. A product as claimed in claim 2 and wherein the a44 barrier member includes further barrier portions whereby o'd the barrier member extends substantially around the entire periphery of the batt.

4. A product as claimed in claim 2 or claim 3 and S including contractible elastic means secured in the product and extending adjacent to at least a portion of the barrier member so as to co-operate with the barrier member in conforming the product to the user's body shape and facilitating comfortable sealing of the product S against the user's body to resist seepage of moisture.

An absorption product in the form of a disposable diaper comprising a moisture permeable facing sheet, a moisture impermeable backing sheet and a fibrous absorbent batt secured between the facing sheet and the backing sheet and including a resilient, closed, gas-filled barrier member extending along at least part of 3777S/MB 10 JBD-93 -i v- i:l i the peripheral regions of the diaper and adjacent to peripheral portions of the batt.

6. A product as claimed in claim 5 and having a reduced-width central portion for location in the crotch region of the user and includes contractible elastic members extending along the respective sides of the diaper in the crotch region and adjacent respective portions of the gas-filled member.

7. A product as claimed in claim 5 or claim 6 and wherein the barrier member includes elongated tubular elements provided around the front and rear waistband regions of the diaper.

8. A product as claimed in any one of the preceding claims and wherein the gas filled member is formed from plastic sheet material sealed to provide the barrier member of the desired shape and configuration, the plastic sheet material extending between spaced portions of the barrier member thereby providing a support structure and l an arrangement for constituting a moisture impermeable 1140 backing sheet for the batt. 4 o^

9. A product as claimed in any one of the preceding 4 claims wherein the gas filled member is formed from polyethylene film and air is used as the gas for filling the member, the film being curled around its longitudinal o b?25 axis and sealed with an overlapping joint.

10. A product as claimed in any one of claims 1 to 9 and wherein the gas filled member is o-f plastic film and air is used as the gas for filling the member, the barrier member comprising two strips of such film material sealed together along sides of the barrier member.

1 1. A product as claimed in any one of the preceding claims and wherein the barrier member is a laminate comprising a plastic film forming an interior layer of the barrier member and a fibrous layer bonded to the plastic film as an exterior layer.

12. A product as claimed in any one of the preceding claims wherein the barrier member is formed with a complex 3777S/MB 11 JBD-93 r shape and is formed from a sleeve of plastic film having a central region in which opposite sides of the sleeve are secured together to define one side of the gas-filled portion of the barrier member.

13. A product as claimed in claim 12 and wherein the barrier member has a gas-filled tubular portion having heat sealing zones along the sides thereof to define a generally hour-glass shape for conforming to the body shape of a user.

14. A method of forming a fluid absorption product and comprising supplying plastic film strip to a forming device and bending the strip to provide a generally tubular form including a cavity extending along the strip, introducing gas through a probe located within the formed tubular cavity, sealing the edge regions of the strip to close the tubular form along its length, sealing the tubular form at desired locations by seduring together opposite walls of the tubular form after they had been -It pressed together whereby a resilient, closed gas-filled barrier member is produced, and securing a fibrous absorbent batt in co-operating juxtaposition with the gas-filled barrier member. 9

15. A method as claimed in claim 14 wherein the tubular form is provided by curling the strip about its longitudinal axis generally around a cylindrical support and sealing the tubular form along an overlapped joint.

16. A method of forming a fluid absorption product comprising supplying two strips of plastic film material in generally face to face arrangement, introducing gas between the sheets of the film, pressing selected portions Sof the film together and establishing heat seals along lines of sealing to provide a tubular gas-filled barrier region, and securing a fibrous absorbent batt in co-operating juxtaposition with the gas-filled barrier member.

17. A method substantially as herein described with reference to Figures 4 to 6 or Figures 7 to 11 of the 3777S/MB 12 JBD--93 A> 7- i «a -13- accompanying drawings or with reference to Figures 7 to 11 and modified in accordance with Figure 12 of the accompanying drawings.

18. An absorbent product produced by any one of claims 13 to 17.

19. An absorbent product substantially as herein described with reference to either Figure 1 or Figure 3 of the accompanying drawings, or with reference to either Figure 1 or Figure 3 modified with a barrier member as described with reference to Figure 2 of the accompanying drawings. t a DATED this 7th day of February 1990 at r a r a JOHNSON JOHNSON By their Patent Attorneys GRTFFITH HACK CO. @99 o po *9 I a ~r 4r 1 7669S/SLV