AU643768B2

AU643768B2 - Tampon for female hygiene

Info

Publication number: AU643768B2
Application number: AU74346/91A
Authority: AU
Inventors: Graham Aspinwall
Original assignee: Kimberly Clark GmbH
Current assignee: Kimberly Clark GmbH
Priority date: 1990-11-02
Filing date: 1991-04-11
Publication date: 1993-11-25
Anticipated expiration: 2011-04-11
Also published as: DE9015123U1; AU7434691A

Description

S F Ref: 160645 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION (ORIGINAL) 43 7 FOR OFFICE USE: Class Int Class So S

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Sr 5555 5 0 Complete Specification Lodged: Accepted: Published: Priority: Related Art: Name and Address of Applicant: Address for Service: Kimberly Clark GmbH Carl-Spaeter-Strasse 17 D-5400 Koblenz-Rheinhafen FEDERAL REPUBLIC OF GERMANY Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Seoo

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Complete Specification for the invention entitled: Tampon for Female Hygiene The following statement is a full description of this invention, including the best method of performing it known to me/us 5845/4 -1- Description The present invention relates to a tampon for feminine hygiene.

A tampon of this kind is described in EP-A-O 149 155. In this known tampon, the strip consists of bicomponent fibers, of fibers having a polyester core and a sheathing of high-pressure polyethylene, said polyethylene having a melting point lower than that of the polyester. The strip is sealed onto the nonwoven ribbon section with high sealing pressure over a length corresponding approximately to the length of the circumference of the tampon blank to provide intimate bonding between the nonwoven ribbon section and the strip over the entire circumference of the tampon blank. This kind of sealing, even if it only extends in discrete lines over the strip, causes the bicomponent fibers to be fused with each other and with the material of the nonwoven ribbon and the sheathing of the bicomponent fibers and the nonwoven ribbon to be deformed in the areas where the sealing pressure is applied.

On the one hand, this results in an unattractive striaticn in the .completed product which, at least subjectively, conveys the impression of a surface structure. On the other hand, undesired fluid channels are formed in the area of the striation on the surface of the tampon and 20 reduces the capillary absorbing capacity towards the interior of the :o tampon.

,:Therefore, the present improvement is based on the object of providing a tampon of the above-described kind which has a smooth, irritation-free surface and is of improved absorbing capacity.

25 Accordingly, there i. disclosed herein a tampon for female hygiene, comprising a tampon body formed of a section of predetermined length of a nonwoven ribbon which is preferably composed of randomly laid fibers, provided with a withdrawal cord, and wound essentially upon itself to form a tampon blank, and a cover formed of a strip of a 30 liquid-permeable, at least partially thermoplastic material whose width corresponds approximately to the length of the tampon and whose length is slightly greater than the circumference of the tampon blank, said o roo strip being secured by heat sealing one end portion thereof to the nonwoven ribbon section such that the opposite free end projects beyond a longitudinal end of the section, said free end being sealed to the outside of the strip, the covered tampon blank being compressed essentially radially to give the final form of the tampon, wherein i/05071 the liquid-permeable strip comprises a fibrous nonwoven material containing cellulose fibers, smooth synthetic fibers and a pulverized thermoplastic binding agent, and wherein the strip is tacked merely with its end portion disposed away from its free end to the nonwoven ribbon section and is laid tightly around the outside of the tampon blank, its free end being sealed over its surface area to the outside of the strip.

Beneficially, the configuration of the liquid-permeable strip enables a mere point-by-point fusion when the strip is tacked to the nonwoven ribbon and eliminates an agglutination the fibers of the strip with each other and with the fibers of the nonwoven ribbon over a large area, including the formation of liquid channels in the tampon surface, is reliably eliminated. Due to the free strip end being bonded over its surface area to the outside of the strip underneath, an e;:traordinary smooth surface is provided and unintentional braking loose of fibers from the nonwoven material is reliably eliminated.

Beneficially, a tampon is provided which has a particularly smooth surface and is of uniform consistency when the nonwoven ribbon section is obtained by tearing it from a continuous length of ribbon material 20 such that at least its end to be placed on the outside of the tampon blank is thinned.

According to a particularly preferred embodiment, the liquid-permeable strip consists of a mixture of rayon fibers, polyester fibers and a thermoplastic polyester binding agent.

Appropriately, the strip further includes a wetting agent causing a particularly effective liquid discharge into the interior of the tampon and acting to prevent body liquid from flowing along the cover.

It has been found particularly advantageous for the liquid-permeable strip to be composed of a mixture of 5 to 15 wt.%, preferably about 11 of rayon fibers, 55 to 75 preferably about 65 of polyester fibers, 15 to 25 wt%, preferably about of a polyester binding agent and/or up to 10 preferably about 6 wt.% of a wetting agent.

According to a preferred, optional embodiment of the improvement, at least in the outside of the cover of the completed tampon the binding agent is glazed by means of thermal treatment. This can be effected in TI, that the completed compressed tampon is delivered past a heat source or /05071 -3that the compression operation is performed simultaneously with a heat treatment, as it is described in DE-3-10 32 477. By "glazing" of the thermoplastic binding agent, it is understood that at least the particles of thermoplastic binding agent located at the surface of the strip are briefly melted to obtain a glassy, smooth surface after the binding agent has cooled off. The surface of the fibers forming the strip, which are not thermoplastic or having a melting point which is significantly higher than that of the binding agent, are not adversely affected by this procedure, and thus the absorbing capacity of the fibers, because these fibers are wetted by the molten binding agent and bonded therewith only over minutest areas without melting themselves.

In the "glazing" operation, care must be taken that the strip material does not contained a too high amount of thermoplastic binding agent and that the temperature is so selected that the strip does not agglutinate with thQ nonwoven ribbon.

A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: *4 a o4.

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Fig. 1 shows an end portion of a nonwoven ribbon section with a withdrawal cord being looped therearound and a strip of cover material being tacked to the ribbon, Fig. 2 shows how the configuration of Fig. 1 is wound up by means of a vacuum winding mandrel to form a tampon blank.

Fig. 3 shows how the free end of the strip is tacked to the outside of the cover of the tampon blank.

S* Fig. 4 shows the compressed completed tampon.

Fig. 5 shows an enlarged cross-section through the tampon of Fig. 4 and illustrates the optional glazing of .the tampon surface.

Sections of continuous length are torn from a continuous nonwoven ribbon formed of randomly laid natural or synthetic fibers by means of a feed device (not shown in detail), comprising a plurality of roller pairs driven at different speed, such that the end portions of said sections are thinned, they gradually decrease in thickness in this area. In Fig. 1, the left-hand side of such a section 1 is shown whose width corresponds approximately to the length of the completed tampon. The above-mentioned thinned portion 2 is disposed on the left-hand end portion of the nonwoven ribbon section 1, seen from the viewpoint of Fig. 1. Displaced inwardly relative to said thinned portion 2, one end portion of a strip 3 is tacked to the surface to the nonwoven ribbon section by thermo-welding in a few discrete or intermittent line-type areas 4. The width of strip 3 corresponds to the width of the nonwoven ribbon section 1 and, after the winding operation has been completed, the length of strip 3 iz slightly greater than the circumference of the tampon blank. Strip 3 can be tacked to the nonwoven ribbon section 1, for example, by means of a roller comprising heated teeth or projections. Strip 3 consists of a smooth and thin nonwoven material which is preferably composed of randomly laid natural or synthetic fibers, with a pulverized thermoplastic binding agent being incorporated between the fibers.

In the preferred embodiment of the improvement, the nonwoven ribbon 1 consists of cotton-rayon fibers and the strip of a mixture of about 11 wt.% of cotton-rayon fibers, about 65 wt.% of polyester fibers, about 20 wt.% of a pulverized thermoplastic polyester binding agent and about 6 wt.% of a wetting agent (Cetail).

As is evident from Fig. 1, the strip 3 extends at least by half of its length beyond the free end 5 of the nonwoven ribbon.

Section 1 which is provided with a withdrawal cord 6 in a manner known per se in the art.

As shown in Fig. 2, the above-described configuration consisting of nonwoven ribbon section 1, the tacked-on strip 3 and the withdrawal cord 6 are then wound-up on a rotating vacuum winding mandrel 7, starting at the right-hand side from the viewpoint of Fig. 1 which is not shown in Fig. 1, such that at the end of the operation the strip 3 is wound upon the outside of the roll of nonwoven material and tightly encloses the latter. Subsequently, the free end 8 of the strip 3, as shown in Fig. 3, is sealed over its surface area to the outside of the strip 3 by means of a heated shoe 9 which is adapted to be moved towards and away from the roll, as is illustrated by arrow 12.

The tampon blank is then withdrawn from the winding mandrel 7 and radially compressed in known fashion co form the completed tampon 10 which is shown in Fig. 4 and preferably includes four expansion folds extending radially inwardly.

Fig. 5 shows a cross-section through a completed tampon which in this state is directly ready for use. However, further smoothening of the tampon surface can be accomplished if, as is shown in Fig. 5 by arrows 11, the surface of the cover formed by strip 3 is heated over a short period of time, so that the bte thermoplastic binding agent starts to melt and glazes after it *fe has cooled down, as has been described above in detail.

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Claims

1. A tampon for female hygiene, comprising a tampon body formed of a section of predetermined length of a nonwoven ribbon which is preferably composed of randomly laid fibers, provided with a withdrawal cord, and wound essentially upon itself to form a tampon blank, and a cover formed of a strip of a llquid-permeab'e, at least partially thermoplastic material whose width corresponds appiroximately to the length of the tampon and whose length is slightly greater than the circumference of the. tampon blank, said strip being secured Ly heat sealing one end portion thereof to the nonwoven ribbon section such that the opposite free end projects beyond longitudinal end of the section, said free end being sealed to the outside of the strip, the covered tampon blank being compressed essentially radially to give the final form of the tampon, wherein the liquid-permeable strip comprises a fibrous nonwoven material containing cellulose fibers, smooth synthetic fibers and a pulverized thermoplastic binding agent, and wherein the strip is tacked merely with its end portion disposed away from its free end to the nonwoven ribbon section and is laid 20 tightly around the d&utside of the tampon blank, its free end being sealed over its surface area to the outside of the strip. Goo:

2. The tampon of claim 1, wherein the nonwoven ribbon section of predetermined length is obtained by tearing it from a continuous length of ribbon materiel such that at least its end portion which is placed on the outside of the tampon blank is of decreased thickness.

3. The tampon according to any one of the preceding claims, wherein the liquid-permeable strip consists of a mixture of rayon fibers, polyester fibers and a thermoplastic binding agent.

4. The tampon of any one of the preceding claims, wherein the 30 liquid-permeable strip contains a wetting agent.

5. The tampon of claim 3 or 4, wherein the liquid-permeable strip consists of a mixture of 5 to 15 preferably about 11 wt.%, of rayon fibers, 55 to 75 preferably about 65 of polyester fibers, 15 to 25 preferably about 20 of a polyester binding agent and/or up to 10 preferably about 6 of a vwetting agent.

6, The tampon of any on of the preceding claims, wherein at least in the outside of the cover of the completed tampon the binding ;/05071 -8- agent is glazed by a thermal treatment. A tampon substantially as hereinbefore described with reference to the accompanying drawings. DATED this FIFTEENTH day of SEPTEMBER 1993 Kimberley Clark GmbH Patent Attorneys for the Applicant SPRUSON FERGUSON S S w S S 0e45 S. 555 S. S S S S 5e S S S. OS OS .5 *504 S .555 S. S 5 550 5 S 55*O*5 S MGI 05071