LU84035A1 - DEFORMATION-RESISTANT HYGIENIC TOWEL - Google Patents

Description

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The present invention relates to a towel! hygienic and, in particular, a sanitary napkin that contains fusible fibers.

One of the traditional methods for forming a sanitary napkin is to assemble it by inverting the underside upward. Next, a fluid-permeable covering material is laid over it with an absorbent veil such as a wood pulp down so that the edges end in the same place. Then, you can optionally add an superabsorbent powder or a sheet of superabsorbent material. If we use I: * a sheet containing an superabsorbent material, it is not essential that this sheet ends in the same place as the other elements. Next, the fluid-permeable envelope and the absorbent web are folded back to essentially form a double thicker. A fluid impermeable screen is then added in order to keep the fold in place and form the stop element for the fluids which the finished towel must contain. The towel thus produced has folded longitudinal edges which are flexible and comfortable.

It is also known to introduce fusible fi-25s into an absorbent fleece. Such a combination is described in United States patent No. 4,059,0H4j. As described in this patent, the fusible fibers are> added in order to increase the absorption capacity I by facilitating the flow of the fluids "30 inside the absorbent layer.

Recently, "Johnson & Johnson" of Milltown, New Jersey, USA, sold under the brand name "SURE & NATURAL" a sanitary napkin of reduced thickness which, as claimed , has an absorption capacity as strong as that of thick sanitary napkins

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► 3 usual sors. The absorbent element of this towel comprises an superabsorbent material mixed with the conventional absorbent layer. The remaining absorbent is of the usual cellulosic type. Even when incorporating an superabsorbent material, this towel did not perform as expected. It has been found that one of the reasons for this disappointing performance was the deformation constraints which the towel could not resist due to its structure.

When the sanitary napkin is worn, the legs of the wearer impose forces directed inwardly along the longitudinal axis. These forces also create a shear effect along this longitudinal axis. It has been found that when the conventional absorbents contain a sufficient amount of a liquid such as menstruation and that when a deformation force is applied, the conventional absorbent does not return to its former shape. This remark is true although the absorbent 20 is surrounded by a non-absorbent envelope. The absorption of menses tends to cause local deformation and upturn along the plane of the towel. This results not only in discomfort due to the deformation of the towel, but also in a negative influence on its absorbent properties.

»J Strong deformation and localized rolling up I of the damp absorbent material may give rise to | | the formation of channels through which the fluid flows! laterally or which otherwise interfere with the general spreading of the fluid through the absorbent material.

According to the present invention, a sanitary napkin is provided along the longitudinal edges of which an absorbent veil is folded. The absorbent material contains fusible fibers which, in combination with the folded longitudinal edges, form an elastic absorbent matrix retaining its shape after significant absorption of fluid. Consequently, a towel produced according to the pre-invention is superior both from the comfort point of view and from the point of view of its absorption capacity compared to a towel having an equal absorbent mass and an absorption capacity. similar.

The present invention will be better understood by referring to the single appended drawing which is a cross-sectional view of a pre-form embodiment.

Ifered with the towel of the present invention. As can be seen in this figure, an I - absorbent layer 10 containing fusible fibers is also - - · <| wrapped in a fluid-permeable casing 16 and it J 15 is folded back below itself to form; i:! closely adjacent edges as shown by: li 1 dashed lines 11. An absorbent layer i | intermediate made of an superabsorbent material i 13 is generally arranged in the center of the absorbent matrix I "20 resting on top of the folded surface i 1 12 of the absorbent material 10, while a screen 14 impermeable to fluids is fixed by an adhesive on the underside of the absorbent layer; j folded in. The transverse ends of the absorbent layer: S 25 are not glued to the edges, but 5; | they are rather sealed by fusion. This fusion I generally appears in the absorbent material in the form of thin, semi-circular clear strips 15 I which are set back from the ends of the towel 30. By not fixing the extreme ends I of the towel, loose and flexible ends are obtained which are more comfortable as ends î linked to the edges themselves.

* The preferred embodiment of the sanitary napkin shown in the drawing has an outer casing which is integral with the absorbent: / .s - ./; 5

Preferred ibant to which it is fused after having deposited this absorbent using the envelope as a support, because the particularly preferred material is that described in the patent of the United States of America 4 · 100.324 · This material not woven has a fabric-like finish and it | consists of a matrix formed in air and cons— | made up of thermoplastic polymer fibers with an average diameter J less than about 10 microns, as well as several individual fibers of wood pulp jî 3 dispersed throughout this matrix and used for | move the microfibers apart, I 'We form this material using initia- -; Also a stream of primary air with the micro-fibers blown in melt, as well as a stream? secondary air containing wood pulp fibers,! then by joining the two turbulent currents and in | Then passing the integrated air stream on | along a forming surface. The aspect similar to | 20 that of a fabric possessed by this material, forms an absorbent element with a pleasant appearance, 1. In the alternative, the advantage of the concept of the present invention lies not only in the ability to merge the ends of the service. 25 viette, but also in the ability to merge absorbent containing fusible fibers with the I ^ layer forming a screen impermeable to fluids, I As mentioned above, the sanitary towel according to the present invention is characterized both by the presence of the folded edge edges and by the incorporation of fusible fibers in the absorbent matrix. Surprisingly, it is this particular combination which is at ij the basis of the resistance to deformation. A ser— i | 35 viette produced in accordance with the teachings of the: | present invention retains at least 9 & 35% of its over-. / - il 11 i 6 r | 1 ['face after absorbing 1 g of menstrual fluid and when it has been worn for a period of at least 1 hour. The surface measured is that which is essentially flat. From this surface, those which are rolled up or deformed outside a plane which is either flat or curvilinear are subtracted 5 according to the total dimensions of the towel and the conformation of the user. Surprisingly, towels with folded edges without fusible fibers undergo permanent deformation. This is also true for corn napkins with fusible fibers, but without J. folded longitudinal edges. These towels that are! generally known as "115 cut napkins" due to the existence of edges ending in the same place on the periphe—

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J rie of the towel, do not have the resistance to dé permanent deformation and rolling up pro- | good when using fusible fibers in i20 a towel of a folded configuration. Likewise, the deformation is particularly important when there is no element according to the present invention and when the thickness of the towel is reduced as is the case in the towel. type | 25 "SURE & NATURAL".

, | It should be noted that this resistance to deformation is particularly important in towels of reduced mass. Towels with between 5 * 08 and 12.7 111111 of absorbent material! 30 are particularly resistant to deformation 'il * * 1 and, in fact, the measures mentioned above have Ί:! were carried out on towels of this type.

Ί! However, in order to ensure resistance to

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| deformation according to the present invention, it is necessary that the absorbent material has a density il of at least 20 g / m2. Better resistance is obtained 3 / i; î i / * I 7! Deformation resistance at higher densities j densities of 150-200 g / m2 are usually preferred. Higher densities can increase stiffness without significantly increasing resistance to deformation. When superabsorbent material is present in towels of this reduced thickness, this type of product has the expected absorption potential, since the absorbency of the towel so designed can be fully utilized.

j Although superabsorbent material is currently preferred, it should be noted that there are others | "Materials with higher absorption capacity i or other desirable properties than we can!" 15 add as a supplement; similarly, a towel can be produced without the presence of this material. Because a towel according to the present invention can keep its shape, the absorbency is used with greater efficiency, so that there is less need to use an additional absorbent.

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Claims (5)

1. Sanitary napkin, characterized in I that it comprises a screen impermeable to fluids and an absorbent veil comprising fusible fibers 5 and whose longitudinal sides are folded, this napkin retaining at least $ 96.5 of its surface; flat after absorption of one gram of fluid and after | have been worn for an hour. 2. Sanitary napkin as claimed; 10 cation 1, characterized in that the absorbent is a j jj mixture of wood pulp fibers and micro-fibers,! 1 Ice mixture being placed in the air. “3. Sanitary napkin according to the claim • 1 cation 1, characterized in that a screen is fused || $ 1 with absorbent veil. if i * 4 · Sanitary napkin according to claim 1, characterized in that an absorbent material | additional is arranged below the face of the absorbent veil which ", is turned towards the body. I 20 5. Sanitary napkin as claimed in one of the claims 1 to 4, characterized in that | that the thickness of the absorbent material is; I between 5.08 and 12.7 mm. j .'ÀXJOjy / i ^ i i I j j ii Ί - îi ij -i 4 Λ; i