EP0404796A1

EP0404796A1 - A method for manufacturing tampons, and a tampon

Info

Publication number: EP0404796A1
Application number: EP89903284A
Authority: EP
Inventors: Erich Guggenberger; Ebbe Hoden
Original assignee: Johnson and Johnson GmbH
Current assignee: Johnson and Johnson GmbH
Priority date: 1988-03-04
Filing date: 1989-02-28
Publication date: 1991-01-02
Also published as: FI904340A0; AR240396A1; SE8800774D0; AU4073389A; SE8800774L; KR900700067A; DK210290D0; WO1989007924A1; DK210290A; SE460700B; ZA891651B; BR8907299A

Abstract

Le tampon décrit est fabriqué à partir d'un ou de plusieurs filaments fins à base de matériau fibreux (6). On produit une ébauche de tampon (1) en enroulant le ou les filaments à base de matériau fibreux selon une configuration en couches croisées autour d'un mandrin (2). Le mandrin est amené à tourner par rapport à un guide-filament (4), lequel est amené à son tour à effectuer un mouvement alternatif par rapport au mandrin dans sa direction longitudinale. Le mandrin en rotation (2) effectue de 0,1 à 5 tours pendant le temps nécessaire au guide-filament (4) pour effectuer un mouvement de va-et-vient. L'ébauche de tampon (1) avec sa configuration en couches croisées est déplacé ou ôté du mandrin avant l'opération de compression de l'ébauche selon la forme de tampon désirée. Le tampon ainsi fabriqué se compose essentiellement d'une ébauche de tampon (1) à configuration en couches croisées compriméessous forme de tampon.The tampon described is made from one or more fine filaments based on fibrous material (6). A tampon blank (1) is produced by winding the fibrous material-based filament (s) in a cross-layered configuration around a mandrel (2). The mandrel is caused to rotate relative to a filament guide (4), which in turn is made to reciprocate relative to the mandrel in its longitudinal direction. The rotating mandrel (2) performs 0.1 to 5 turns during the time necessary for the filament guide (4) to perform a reciprocating movement. The tampon blank (1) with its cross-layered configuration is moved or removed from the mandrel before the blank compression operation in accordance with the desired tampon shape. The tampon thus produced essentially consists of a tampon blank (1) with a cross-layered configuration compressed as a tampon.

Description

A method for manufacturing tampons, and a tampon

The present invention relates to a method for manufacturing a tampon, particularly, but not exclusively, a sanitary tampon, with the use of one or more thin, optionally crimped filaments of fibre material which are formed into a porous tampon blank, which blank, optionally together with a with¬ drawal string or cord anchored therein, is compressed to a final tampon form. The invention also relates to a tampon produced in accordance with the novel method.

Tampons are normally produced from relatively very coarse cotton tows, from which a predetermined length is cut and folded or wound to form a tampon blank, which is thereupon compressed to form a tampon. Tampons of this conventional construction are not particularly well suited for use as sanitary tampons. It is extremely difficult to produce a cotton tow of uniform thickness and consequently the tampons produced from such tows will contain varying quantities of cotton and therewith exhibit mutually different swelling and absorption properties. Moreover, sanitary tampons which are produced from tampon blanks obtained by conventional winding of a coarse cotton tow tend to lengthen considerably when removed, as a result of sliding between the turns, resulting in sanitary drawbacks, among other things. Proposals have also been made to produce sanitary tampons from thin fibre material filaments, in which the filaments extend in the longitudinal direction of the tampon; cf for instance US-A-2,934,068. The filaments may consist of single fibres, thereby favourably avoiding loosening of fibres. The absorbenc of the tampon can be enhanced by crimping the filaments, e.g., in accordance with SE-B-331 882, whereby by filaments will cross one another at a great number of locations in a desirable fashion, resulting in an improved capillary action and thus also in enhanced absorbency. Orientation of the filaments or ^'fibres in the longitudinal direction of the tampon, however, has a disadvantage, especially in the case of a sanitary tampon, since such filament orientation impairs the radial integrity or compactness of the tampon, which may have troublesome consequences both when inserting and removing a tampon. In fact, such a tampon can only be inserted with the aid of an insertion sleeve, which greatly increases the overall costs involved.

An object of the present invention is to provide a novel and advantageous method of manufacturing tampons in which the aforesaid drawbacks are avoided, at least to a great extent.

To this end it is suggested in accordance with the invention that when practising a method of the kind described in the introduction, the tampon blank is produced by winding the filament or filaments of fibre material into a cross-ply configuration or braid on a mandrel which is caused to rotate relative to a^' filament guider which, in turn, is moved reci- procatingly in relation to the mandrel in the longitudinal direction thereof, said mandrel being rotated through 0,1-5 revolution during the time taken for the filament guider to move backwards and forwards once, and the cross-ply configura¬ tion forming the tampon blank being doffed from the mandrel . prior to compressing said blank to its intended tampon form. As a result of winding the filament or filaments into a cross-ply configuration in accordance with the invention there is obtained between the ends of the tampon a relatively large angle between the coiled filaments and a radial plane through the tampon, which results in a high degree of radial integrity of the tampon in use and also a high degree of axial integrity and dimensional stability of the tampon both prior to and subsequent to use, while, at the same time, enhancing the absorbency of the tampon as a result of the large number of intersection points between the filaments in the superimposed coil or winding layers. When practising the method according to the invention, the fibrous filament or filaments used may comprise endless single fibres, or yarn made from staple fibres or other short fibres of any suitable material whatsoever. An advantage is gained when the filament used comprises a yarn, e.g. of cotton, which is produced from several individual preyarns, thereby providing a yarn which will vary only very slightly in weight per unit of length, enabling tampons of substantially the same weight to be produced by coiling or winding equal lengths of yarn. It will be understood that yarns formed from combinations of endless fibres and fibres of finite lengths can be used and that different types of filaments or yarns can be used in the manufacture of one and the same tampon. For example, for the purpose of producing a tampon whose fibres will not tend to loosen there may be firstly used a filament formed from fibres of finite length, e.g. staple fibres, while producing the outer layers of each tampon from filaments formed from endless fibres.

It will be understood that the technique for producing a cross-ply configuration is well known in other contexts, and hence the apparatus used to wind or coil the fibre material filament or filaments into a cross-ply configuration in accordance with the invention will not be described in detail. However, reference can be made in this regard to

SE-C-84634, which illustrates and describes one of the many known apparatus for coiling to a cross-ply configuration or ball.

For the purpose of increasing the number of desired fila¬ ment intersection points, prior to being wound into said cross-ply configuration, at least a part of the fibre material filament or filaments can be knitted or plaited to form at least one tow which is wound to form a cross-ply configuration, preferably while being held stretched. For example, at least a part of the fibre material filament or filaments can be circular-knitted or plaited to form at least one tubular tow which is wound into a cross-ply configuration whilst being held streched.

If desired, for instance in order to economize on filaments, the filament or filaments or tow or tows of fibre material can be wound around an absorbent annular core previously fitted to the mandrel and, for instance, comprising a suitable open-pore foamed plastic.

As indicated in the aforegoing, for the purpose of preventing loosening of the fibres, at least the outer layers of the tampon blank of cross-ply configuration can be formed by winding or coiling one or more filaments which comprise at least substantially continuous fibres. Alternatively, or in addition hereto and for the same purpose, at least the outer layers of the tampon blank of cross-ply configuration is formed by winding or coiling one or more filaments which consist entirely or partially of heat-sealable material and which can be heated to heat-sealing temperature prior to compressing the tampon blank, preferably immediately prior to coiling the filament or filaments.

As beforementioned, the invention also relates to a novel and advantageous tampon, particularly, although not exclusi¬ vely, a sanitary tampon, which comprises substantially one or more thin, optionally crimped fibre material filaments and optionally a withdrawal string or cord anchored in the fibre material, and which, for the purpose of avoiding the drawbacks recited in the introduction, substantially comprises a tampon blank of cross-ply configuration which has been compressed to tampon form, said tampon blank optionally embracing a core of absorbent material. For the purpose of enhancing the absorbency of the tampon, at least a part of the fibre material filament or filaments may advantageously have the form of one or more knitted or plaited, suitably stretched tows. For example, at least a part of the fibre material filament or filaments may have the form of one or more circular-knitted or tubular-plaited, stretched tows. For the purpose of increasing the stability of the tampon, at least the outer layer of an advantageous embodiment of the tampon consists completely or partially of one or more filaments of heat-sealable material, said filaments being bonded together at their points of intersection by heat sealing, so as to form a network.

The invention will now be described in more detail with reference to the accompanying drawings, in which

Figure 1 illustrates schematically the manufacture of a tarn- pon blank by winding or coiling a filament to form a cross- ply configuration;

Figure 2 illustrates schematically compression of a tampon blank to a tampon;

Figure 3 illustrates a tow knitted from a fibrous yarn;

Figure 4 illustrates the tow of Figure 3 in a stretched state

Figure 5 illustrates a tubular tow formed by plaiting fibre material filaments; and

Figure 6 shows the tow of Figure 5 in a stretched state.

Figure 1 illustrates a tampon blank 1 of cross-ply configu¬ ration during manufacture. The blank is mounted on a shaft 2 which rotates in the manner illustrated by the arrow 3. The reference numeral 4 designates a filament guider which is arranged to move backwards and forwards along the shaft 2, in the manner shown by the broken arrows 5, in order to lay a fibre material filament 6 in a desired fashion, said filament being taken from a filament supply not shown. In the case of the illustrated embodiment, the shaft 2 rotates two revolutions in the time taken for the filament guider 4 to move backwards and forwards once.

The compressing device illustrated in Figure 2 includes four jaws 7 each of which has two mutually perpendicular working surfaces 8 intended to be brought into pressure-exerting engagement with a tampon blank. The jaws 7 are reciprocatingly movable between the forwardly displaced position, in which the working surfaces 8 are shown in full lines, and the with¬ drawn position, in which the working surfaces 8 are shown in broken lines. The compressing device includes a further four jaws 9 each of which has a working surface 10 which, when seen in cross-section, is in the form of a cirtular- arcuate, cupped groove and which is also intended to be pressed against the tampon blank. The jaws 9 are recipro¬ catingly movable between the withdrawn position, shown in full lines, and an advanced or forwardly displaced position, in which the working surface 10 is indicated in broken lines. When the jaws 7 are located in their forward position, the working surfaces 8 on said jaws function as guide surfaces for the jaws 9. When all jaws 7, 9 are withdrawn, a tampon blank, indicated in broken lines 11, can be inserted axially between the jaws. The jaws 7 are then advanced so as to compress the tampon blank to the cross-sectional shape shown by the hatched area in Figure 2. The jaws 9 are then advan¬ ced so as to compress the tampon blank, such that the blank will have a substantially circular cross-sectional shape and be fully incircled by the working surfaces 10 of the four forwardly displaced jaws 9. Subsequent to withdrawing all jaws 7, 9, the finished tampon can be removed from the compressing device.

Figure 3 illustrates a knitted yarn tow 12 suitable for use in the manufacture of the inventive tampon. Prior to being wound or coiled to a cross-ply configuration, such as the configuration illustrated in Figure 1 for instance, the tow is preferably stretched to the shape illustrated at 13 in Figure 4.

Figure 5 illustrates a tubular-plaited tow 14 which is suit¬ able for use when producing the inventive tampon and which prior to being wound or coiled to a cross-ply configuration, for instance the cross-ply configuration shown in Figure 1, is preferably stretched to the form illustrated at 15 in Figure 6.

It will be understood that the invention is not restricted t the embodiments described with reference to Figures 1-6, but can be realized in any desired manner within the scope of th invention as defined in the following claims. Thus, it will be seen that a cross-ply configuration can be obtained with the aid of a filament guider arranged for movement around an reciprocatingly along a stationary shaft or mandrel, and tha the reciprocating movement of the filament guider in Figure 1 can be replaced with an axial reciprocating movement of the rotating shaft or mandrel. Any suitable material in filament form can be used to manufacture the inventive tampon, and th tampon blank can be compressed in a manner different to that shown, for example so as to obtain a tampon with a rounded en Although no withdrawal string or cord has been shown in the drawings, it will be understood that such a string or cord shall be anchored in the tampon blank in some suitable manner prior to compressing the blank to the final tampon form. As before mentioned, mutually different filaments having mutuall different properties can be used in the construction of the tampon blank, this possibility being used primarily to construct a tampon in which the fibres in the outer surface thereof will not tend to loosen while the interior of the tampon has optimum liquid absorption and retention properties Suitably, the mandrel is caused to rotate 0.33-3, preferably 0.5-2, revolutions during the time taken for the filament guilder to move backwards and forwards once. The fibre material may comprise a crimped yarn made from a plurality, e.g. 20, preyarns and each preyarn may comprise a plurality, e.g. 50 to 100, single fibres of , for instance, regenerated cellu¬ lose.

Claims

1. A method for manufacturing a tampon, particularly, but not exclusively, a sanitary tampon, with the use of one or more thin, optionally crimped aiifibre material filaments ( 5 which are formed into a porous tampon blank (1) , which blank, optionally with a withdrawal string or cord anchored therein, is compressed to a final tampon form, characterized in that the tampon blank (1) is produced by winding the filament or filaments (6) of fibre material into a cross-ply

10 configuration on a mandrel (2) which is caused to rotate relative to a filament guider (4) which, in turn, is moved reciprocatingly relative to the mandrel in the longitudinal direction thereof, said mandrel being caused to rotate 0,1-5 revolutions during the time taken for the filament guider to

15 move backwards and forwards once, and the cross-ply configura tion forming the tampon blank (1) being doffed from the mandrel prior to compression of said blank to its intended tampon form.

20 2. A method according to Claim 1, characterized in that, prior to winding said fibre material filament or filaments, at least a part of the filament or filaments (6) is knitted or plaited to form at least one tow (12-15) which is wound to form a cross-ply configuration, preferably in a stretched

25 state.

3. A method according to Claim 2, characterized in that a part of the fibre material filament or filaments (6) is circulars-knitted or plaited to form at least one tubular tow

30 (14, 15) which is wound to a cross-ply configuration while in a stretched state.

4. A method according to any of Claims 1-3, characterized in that the filament or filaments (6) or the tow or tows

*" (12-15) of fibre material are wound around an annular absorbent core pre-fitted to the mandrel (2) .

5. A method according to any of Claims 1-4, characterized in that at least the outer layers of the tampon blank (1) of cross-ply configuration are formed by winding one or more filaments (6) which are comprised at least substantially of continuous fibres.

6. A method according to any of Claims 1-5, characterized in that at least the outer layers of the tampon blank (1) of cross-ply configuration are formed by winding one or more filaments (6) which comprise completely or partially a heat- sealable material and which are heated to heat-sealing tem¬ perature prior to compression of the tampon blank, suitably immediately prior to being wound.

7. A method according to any of Claims 1-6, characterized in that the mandrel (2) is caused to rotate 0.33-3, suitably 0.5-2, revolutions during the time taken for the filament guider (4) to move backwards and forwards once.

8. A tampon, particularly, but not exclusively, a sanitary tampon, comprising at least substantially one or more thin, optionally crimped filaments (6) of fibre material and optionally a withdrawal string or cord anchored in said fibre material, characterized in that the tampon comprises substantially a tampon blank (1) of cross-ply configuration which has been compressed to tampon form, optionally around a core of absorbent material.

9. A tampon according to Claim 8, characterized in that at least a part of the fibre material filament or filaments (6) therein have the form of one or more knitted or plaited, preferably stretched tows (12-15) .

10. A tampon according to Claim 8, characterized in that at least a part of the fibre material filament or filaments (6) therein has the form of one or more circular-knitted or tubular-plaited, stretched tows (15) .

11. A tampon according to any of Claims 8-10, characterized in that at least the outer tampon layers are formed completely or partially from one or more filaments (6) of heat-sealable material which have been bonded together at their mutual points of intersection by heat-sealing, to form a network.