PROCESS FOR MAKING A COMPOSITE ELASTIC TAPE, ELASTIC TAPE SO OBTAINED AND PANTY DIAPER COMPRISING SAID ELASTIC TAPE

Abstract

Disclosed is a process for making a composite elastic tape, elastically extendable along its longitudinal direction, including: providing a tape of elastic material having a main elongation direction; providing first and second tapes of fibrous and porous material; cutting the tape of elastic material into strips along the direction; tensioning the strips of elastic material along the direction to elastically lengthen and distance them; arranging the first and the second tape of fibrous and porous material respectively above and below the tensioned, elastically elongated and spaced strips; and fixing the strips while being tensioned, elastically elongated and spaced, between the first and the second tape of fibrous and porous material in an undeformed condition, to make a composite elastic material shaped like a tape. Also disclosed is the composite elastic tape thus obtained, suitable for the waist region of a diaper as well as other products incorporating such tape.

Claims

1. Process for making a composite elastic tape comprising the steps of: providing a tape of elastic material having a main elongation direction; providing a first and a second tape of fibrous and porous material, of the process comprising: cutting said tape of elastic material into strips along said direction; tensioning said strips of elastic material along said direction so as to elastically lengthen them and distance them; arranging said first and said second tape of fibrous and porous material respectively above and below said tensioned, elastically elongated and spaced strips; fixing said strips while being tensioned, elastically elongated and spaced, between said first and said second tape of fibrous and porous material in an undeformed condition, to make a composite elastic material shaped like a tape.

2. The process for making a composite elastic tape according to claim 1, wherein said step of cutting said tape of elastic material comprises the step of cutting strips with a width of between 5 mm and 100 mm.

3. The process for making a composite elastic tape according to claim 1, wherein the step of spacing said strips comprises the step of spacing them with a distance of between 5 mm and 60 mm.

4. The process for making a composite elastic tape according to claim 1, wherein said step of fixing said tensioned, elastically elongated and spaced strips between said first and said second fibrous and porous material comprises the step of spraying glue, alternatively on the sides of said first and second tape of fibrous and porous material facing towards said tensioned, elongated and spaced strips, before being arranged above and below them, or on the sides of said tensioned, elastically elongated and spaced strips before being coupled with said first and second layers of fibrous and porous material.

5. The process for making a composite elastic tape according to claim 1, wherein said step of fixing said strips while they are tensioned, elastically elongated and spaced, between said first and said second tape of fibrous and porous material comprises the step of passing said composite elastic material shaped like a tape into heat-sealing rollers.

6. Composite elastic tape that is made by the process according to claim 1.

7. Panty diaper comprising an absorbent central body, comprising the composite elastic tape according to claim 6, wherein said composite elastic tape is closed on itself as a ring and fixed along a first edge to said absorbent central body, and is adapted to surround the waist of a user so as to make said diaper wearable as a panty.

8. The panty diaper according to claim 7, wherein said composite elastic tape is partially folded on itself along a second edge distal to said absorbent central body, so as to superpose at least two of said strips of elastic material, increasing and at least doubling the elastic holding force at the user's waist.

9. The process for making a composite elastic tape according to claim 4, wherein said step of fixing said strips while they are tensioned, elastically elongated and spaced, between said first and said second tape of fibrous and porous material comprises the step of passing said composite elastic material shaped like a tape into heat-sealing rollers.

10. Composite elastic tape that is made by the process according to claim 2.

11. Composite elastic tape that is made by the process according to claim 3.

12. Composite elastic tape that is made by the process according to claim 4.

13. Composite elastic tape that is made by the process according to claim 5.

14. Composite elastic tape that is made by the process according to claim 6.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Further features and advantages of the invention shall appear more clearly from the following description of a preferred embodiment, made by way of an indicative and non-limiting example with reference to the figures, in which:

[0037] FIG. 1 is a schematic representation of a system which carries out a process for manufacturing a composite elastic tape according to the invention;

[0038] FIG. 2 is a schematic representation of the composite elastic tape according to the invention, ideally divided into the different construction steps of the process of FIG. 1;

[0039] FIG. 3 is a simplified top plan view of a portion of composite elastic tape according to the invention;

[0040] FIGS. 4 and 5 show, in a simplified axonometric view, a diaper of the panty type comprising the composite elastic tape of FIG. 3, and a detail thereof, respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The steps of the process for manufacturing a composite elastic tape 100 according to the invention are described below, with reference to the system diagram illustrated in FIG. 1.

[0042] The process essentially comprises the steps of: [0043] unwinding, from a first reel 7, a web 1 of elastic material having a main elongation direction x; [0044] longitudinal cutting of said web 1 of elastic material into strips 2 along said direction x; [0045] tensioning and elongation of said strips 2 of elastic material along said direction x, according to the degree of force preferred or imposed by the regulations; [0046] unwinding, from a second reel 11, a first web 10 of fibrous and porous material, for example TNT, above said strips 2; [0047] unwinding, from a third reel 21, a second web 20 of fibrous and porous material, for example TNT, below said strips 2; [0048] coupling said tensioned strips 2, elastically elongated and spaced, of elastic material with said first 10 and second 20 strips of fibrous and porous material kept in an undeformed state, to obtain a composite elastic material shaped like a tape 100, substantially having the width of said tapes 10, 20 of TNT.

[0049] In order to carry out said coupling, said process comprises, in the illustrated preferred variant, the step of spraying glue 3 on the sides 10′, 20′ of said first 10 and second 20 tape of fibrous and porous material facing said elongated strips 2 before being arranged above and below them.

[0050] Said glue 3 could be sprayed on the whole surface of the sides 10′, 20′, or, more advantageously, it could be sprayed locally along only the portions of tape of fibrous and porous material which will correspond, in contact, with the strips 2 of elastic material.

[0051] Alternatively, the glue could be sprayed directly on the sides of said tensioned strips 2, elastically elongated and spaced, before being coupled with said first and second layers of fibrous and porous material. In this way, there would be an advantageous saving on the quantity of glue used.

[0052] To increase said coupling between the layers, or as an alternative to the aforementioned spraying step of glue 3, said process comprises the step of passing said elastic composite material shaped as a tape 100 between heat-sealing rollers 4.

[0053] The design of this heat sealing may be of various types and decorations to meet the market demands on the finished product that will then be made, namely the diaper.

[0054] It is clear that in more simplified alternative variants, the coupling of the layers may also take place by means of gluing only or hot welding only with heat-sealing rollers.

[0055] FIG. 2 specifically illustrates the process steps with particular attention to what happens to the elastic material, identifying four process areas: [0056] a zone A for longitudinally cutting the strips of elastic material 1 into strips 2; [0057] a zone B for tensioning and elongating said strips 2; [0058] an overlapping zone C of said strips 2 with the two tapes 10, 20 of fibrous and porous material; [0059] a zone D for welding the layers to obtain the composite elastic tape 100.

[0060] As is clear from the diagram in FIG. 2, the tensioning and elongation step of the strips 2 of elastic material along said direction x automatically and advantageously causes their thinning and spacing.

[0061] At the moment of the coupling step with the tapes 10, 20 of fibrous material, said strips 2 are detached from each other by a suitably defined distance “d”.

[0062] By way of example only, said strips 2 of elastic material may be cut with a width of between 5 mm and 100 mm, and the distance “d” left between said strips 2 of elastic material when elongated may have a size of between 5 mm and 60 mm.

[0063] After gluing and/or welding, the composite elastic tape 100 appears itself as an alternation, in the transverse direction to the x direction, of elastic strips 2 of composite material and bands 8 of only superimposed porous and breathable fibrous material (FIG. 3).

[0064] Air flows through these bands 8, which is essential to make the tape 100 breathable and ensure maximum comfort to the diaper on which it will be fixed.

[0065] Upon release of the elastic strips 2, the composite elastic tape 100 retracts and curls to be able to lengthen in use.

[0066] With reference to FIG. 4, a diaper 5 is shown comprising an absorbent central body 6 and a composite elastic tape 100 closed on itself in a ring and fixed, along a first edge thereof 100′, to said absorbent central body 6.

[0067] Said ring-closed composite elastic tape 100 is adapted to encircle the waist of the user, be it a child or an adult, so as to make said diaper 5 wearable as a panty.

[0068] With particular reference to FIG. 5, a detail of a second free edge 100″ of said composite elastic tape 100, distal to the absorbent central body 6 and substantially acting as a belt area, is illustrated.

[0069] To increase, and at least double, the elastic holding force, and therefore the force exerted by the material at the user's waist, said composite elastic tape 100 is partially folded on itself, so as to overlap at least two of said strips 2 of elastic material.

[0070] The fixing of said second edge 100″ in a folded configuration on itself still takes place by means of a heat welding step, before the ring closure and the application of the tape 100 to the absorbent central body 6 of the diaper 5.