EP1106723B1 - Hydrophilic cotton skin cleansing article having two different external surfaces - Google Patents

Abstract

The pad (1), made from 100% cotton fibres and of a weight of at least 150 g/m<2>, has two different outer faces (2, 3). At least one of the outer faces has a series of recessed lines (4, 5, 6) 1-8 mm apart and at least 0.25 mm deep. The pad has a resistance to traction of at least 20 N in one direction and 16 N in the other.

Description

The invention relates to a hydrophilic cotton-based pad having a basis weight of at least 150 g / m ² , having two different faces and intended for the care of the skin.

In the following text, the term "hydrophilic cotton swab" includes all product cut into a format that essentially comprises cotton fibers in a 70 to 100 per cent of cotton fiber and 0 to 30 per cent of artificial or synthetic fibers. These are, for example, fibers thermofusibles based on polyolefins.

Skin care includes body care, facials, and especially beauty care using cosmetics: the make-up removal and facial makeup, baby care: toilet and change of baby, etc.

Most of the products or cotton wool pads present on the market are in the form of cut-off formats: round (commonly referred to as cleansing discs), oval or square. They are often composed of a mixture of cotton fibers of different grades or a blend of cotton fibers and other fibers according to the desired product or the manufacturing process used. They're from homogeneous composition throughout their thickness and have external structural faces and identical compositions. They are symmetrical.

Most often, there is no differentiation of use between the two faces of the product. The surface condition is the same on both sides. We use for example indifferently a face for removing make-up or cleansing the skin by applying a make-up removal product or toilet milk and the other side to absorb the excess of product without difference in efficiency between the faces. When applying a aqueous cosmetic product such as a milk or an emulsion on the skin, a great part of the product is absorbed by the buffer.

Some products marketed for cosmetic use have two sides different: they are bifaces. But the two faces are often distinguished essentially visually and not always functionally.

A first stamp (D) comprises a sheet consisting of an overlay of sails of card, itself surrounded by two outer sails of carde previously calendered. The association can be done by collage. The two sails can be differentiated by the more or less important calendering and the case appropriate, by a printed pattern.

A second buffer (E) consists of a sheet also consisting of a superposition of carded sails on which is deposited a hydrolized nonwoven, before cutting.

When the sails of cards are made up of one hundred percent of cotton, the hydrolized nonwoven is a mixture of artificial fibers and fibers synthetic and more specifically viscose and polyester.

The nature of the surface nonwoven is therefore different from that of the tablecloth central in the latter case.

Other biface products have been described in the prior art.

For example, in the field of nonwovens, European Patent Application No. 0 750 062 discloses skin-cleansing articles which are both gentle to the skin and sufficiently strong to allow friction on the skin without causing irritation. or lesions on the latter. The scrubbing action allows the removal of impurities and dead cells from the surface of the skin. These articles comprise a preferably hydrolized nonwoven substrate, having a basis weight of 20 to 150 g / m ² , characterized by a specific coefficient of friction. The substrate preferably comprises at least in part long fibers capable of disengaging from the main surface under the action of friction while remaining attached to the substrate. It may be composed of a mixture of hydrophilic and hydrophobic fibers or purely hydrophilic or purely hydrophobic fibers. At least one face of the substrate used essentially provides the cleaning function of the skin. It also serves as a support for cleansing or makeup removers such as lotions or milkshakes. In the case where the article cleaning the skin has two different faces, the nonwoven substrate is associated with other layers made of different materials. If the cleaning article consists only of the nonwoven substrate, the two faces of the article are identical and are not distinguishable. The article is thus similar to a dry wipe whose two faces can be used indifferently from one another to clean the skin.

French Patent No. 2,052,089 describes an element made of wadding or cotton consisting of at least two layers of different qualities, held together by padding, or by compression while remaining bouffant and soft in contact with the skin. One of the faces is especially suitable for a pre-make-up and the other face complete the make-up removal. The differentiation of the two faces here rests on the nature or quality of the two layers: they can be made of different or of the same material of different qualities. This is a product complex.

The Applicant in his French Patent Application No. 99 07612 not yet Published describes a product consisting of one hundred percent hydrophilic cotton fibers comprising at least first and second outer layers, the first layer consisting of fine fibers having a low micronaire a soft side and the second layer consisting of fibers having a subscript higher micronaire forming a cleansing face, called "scratching". The faces are differentiate by nature of cotton fibers.

European Patent Application No. 0 405 043 relates to a buffer for apply and / or remove liquid or semi-solid substances, including at least three superimposed layers of absorbent fibrous material such as cotton. Each of the two outer layers is compressed by a uniform tightening on the entire face of the layer and may have additional compression zones by marking a pattern. The central layer is not compressed and forms the heart Absorbent buffer. The three layers are superimposed so as to form a sandwich structure. The two outer faces may have different patterns and be more or less compressed. This product intended for the application of a cream or a liquid is not sufficiently strong if it is used for removing makeup or cleansing the skin. Indeed, frictional forces are exerted on the skin with the buffer moreover, supports a product wetting on its surface. In addition, the Cohesion of the layers between them is insufficient, because of the sandwich structure of the product: three distinct layers superimposed and bound by their edges.

It follows from the foregoing that there is no product or cotton wool pad, "thick", that is to say having a basis weight of at least 150 g / m ² , sufficiently resistant to effectively clean the skin without irritating it and having two different external faces, having different characteristics and properties.

Another object of the invention is to provide a buffer where the two faces are differentiated without altering the nature of the cotton fibers or the quality of the cotton, the differentiation being done not only at the surface of the buffer but one of the faces in the thickness of the buffer.

The invention also aims to provide a resistant buffer and keeping a good cohesion.

The object of the invention is also to provide a cotton wool pad having a basis weight of at least 150 g / m ² which comprises two distinct faces, one intended for skin care, in particular for cleaning the skin and the application of makeup or make-up cosmetics, and the other softer and absorbent, intended to absorb the excess product applied.

For make-up removal, we are looking for a buffer that optimizes the effectiveness of the cleansing with make-up removers, making a single pass of the tampon on the skin, in particular the face of the pad intended for this purpose.

The user can distinguish the faces with the use: to the touch, in contact with the skin or applying skin care products, and also visually.

The object of the invention is to obtain a buffer whose face intended for skin care, makes it possible to receive aqueous cosmetic products in delaying their absorption and penetration into the buffer.

Another object of the invention is to provide methods of manufacturing these buffers, simple, avoiding the preparation of cotton tablecloths of composition and complex structure.

The invention relates to a hydrophilic cotton pad for skin care, having a basis weight of at least 150 g / m ² and having two different outer faces whose fibers are bonded.

According to an essential characteristic of the invention, the first external face comprises hollow streaks with a spacing e ₁ between the striations of between 1 and 8 mm and a stripe depth p of at least 0.25 mm and in that the tensile strength of the buffer is at least 20 N in the running direction and at least 16 N in the cross direction according to a test method given in the description which follows.

According to another essential characteristic of the invention the first external face comprises recessed ridges with a spacing e ₁ between the striations of between 1 and 8 mm and a stripe depth p of at least 0.25 mm and that at least 50 percent of the fibers are bound.

According to an advantageous characteristic of the invention, the spacing e ₁ between the ridges of the first face is between 1.2 and 5.5 mm and preferably between 2 and 4 mm.

According to a preferred characteristic of the invention, the depth p of the streaks of the first face is at least 0.40 mm and preferably at least 0.50 mm.

According to another characteristic of the invention, at least 60 percent of the Buffer fibers are linked.

In order to improve the efficiency of the application of aqueous products such as cosmetics on the skin or the cleaning of the skin with the help of aqueous make-up removers, the first outer surface of the tampon agent delaying the absorption of these aqueous products.

The subject of the invention is also processes for manufacturing the buffer of hydrophilic cotton according to the invention.

A first method consists in providing a cotton ply, hydrolyzing a first external face of the ply by means of water jets whose axes are spaced from each other by a distance of between 1 and 5.5 mm with a contribution in energy of at least 1.4 x 10 ^-3 kwh / m ² , and hydrolyze the other outer face of the sheet by means of water jets whose axes are spaced a distance of between 0.4 and 1.2 mm with an energy input of at least 0.9 x 10 ^-3 kwh / m ² .

A second method consists of providing at least two sheets of cotton hydrophilic from laundered bleached fibers or bleached webs, mark the first web so as to print streaks having a spacing between striations between 1 and 8 mm and a streak depth of at least 0.25 mm on one side of the first layer, the marking pressure being sufficient to obtain a buffer resistance of at least 20 N in the running direction and at least 16 N in the cross direction according to the test method given in the description which follows, mark or consolidate the second layer, and combine the two layers thus obtained, the two marked and / or consolidated faces being located outside the buffer.

• la figure 1 représente une vue en perspective d'un tampon selon l'invention ;
• la figure 2 représente une coupe transversale schématique suivant la ligne II-II du tampon représenté à la figure 1 ;
• la figure 3A représente une vue agrandie du tampon représenté à la figure 2, au niveau d'une strie, qui correspond à un mode de réalisation utilisant la technique d'hydroliage,
• la figure 3B représente une vue agrandie d'un tampon correspondant à un autre mode de réalisation utilisant la technique de marquage ; et
• les figures 4A, 4B, 4C et 4D représentent différents états de surface illustrant des tampons selon l'invention.

Other features and advantages of the invention will appear in more detail in the description which follows and with reference to the appended drawings in which:

• Figure 1 shows a perspective view of a buffer according to the invention;
• Figure 2 shows a schematic cross section along the line II-II of the buffer shown in Figure 1;
• FIG. 3A represents an enlarged view of the buffer represented in FIG. 2, at a streak, which corresponds to an embodiment using the hydrolysis technique,
• Fig. 3B is an enlarged view of a buffer corresponding to another embodiment using the marking technique; and
• FIGS. 4A, 4B, 4C and 4D represent different surface states illustrating buffers according to the invention.

The buffer according to the invention is a cut product of round, oval, square or any other shape. It has a basis weight of between 150 and 400 g / m ² and preferably between 180 and 300 g / m ² . It is based on cotton and essentially comprises absorbent hydrophilic cotton fibers. More specifically, it comprises from 70 to 100 percent of uniform quality cotton fibers and from 0 to 30 percent of artificial fibers such as viscose fibers, synthetic fibers such as polyester fibers, two-component fibers (polyester / polyester, polypropylene / polypropylene or polyester / polypropylene), or mixtures thereof.

The pad comprises a single or multi-ply web of cotton. It may comprise two superimposed layers, each formed of a layer of cotton. The buffer can still be made of three layers, a central layer formed of a cotton fiber web and two outer layers consisting of example of cotton carding sails around the central layer.

According to the embodiment of the buffer shown in Figures 1 to 3B, the buffer 1 comprises a first outer face (2, 2 ') and a second outer face (3, 3'). The first outer face (2, 2 ') comprises ridges (4, 4'), (5, 5 ') and (6, 6') here arranged parallel to each other. The spacing e ₁ between the streaks is between 1 and 8 millimeters, preferably between 1.2 and 5.5 millimeters and more preferably between 2 and 4 millimeters. The depth p of the ridges is at least 0.25 millimeters, preferably at least 0.50 millimeters. The striations form hollows (7, 7 ') and bumps (8, 8') visible to the naked eye. The second outer face (3, 3 ') also comprises striations 9 and 10 much finer and closer to each other. The spacing e2 between the ridges of this second face is between 0.4 and 1.2 millimeters.

The depth of the streaks is lower on this second face, compared to that from the first side. In some embodiments of the buffer, it is of the order 0.1 millimeter.

FIGS. 4A, 4B, 4C and 4D illustrate other embodiments of the buffer according to the invention.

The striations can form on the surface of the first external face (2, 2 ') continuous lines (Figures 1, 4A and 4B), broken lines (Figure 4C), lines straight lines (Figure 1), curved lines (Figure 4A) or broken lines (Figure 4B). Some the arrangement and distribution of the streaks, or their geometry, it is important that a number of hollows and bumps be formed at the level of the first face of the stamp.

Another essential characteristic of the buffer according to the invention is its particularly high tensile strength both in the direction of travel and in the direction of travel through, in comparison to other known products. Because of this resistance, the buffer does not deform with use.

In the text that follows, the tensile strength corresponds to the resistance to measured traction on a specimen and defined by the test method described below.

Samples or test pieces of 57 millimeters long by 25 millimeters wide are cut into buffers according to the invention. A first series of samples is cut to obtain the greatest length of the sample in the running direction to measure the resistance in the running direction. A second set of samples is cut in order to obtain the largest length of the sample in the cross direction to measure the resistance in sense through.

The resistance measurement is carried out by means of a dynamometer.

The tensile strength (RT) of the buffers according to the following invention is measured the method below. The sample is placed between two jaws separated from 30 millimeters, in the direction of the length of the sample. We jog the jaws a speed of 100 mm / min and the maximum force exerted before rupture is measured. This maximum force is the tensile strength.

• des tampons A selon l'invention, constitués de cent pour cent de fibres de coton ;
• des tampons B également constitués de cent pour cent de fibres de coton, fabriqués par la demanderesse à partir de nappes décrites dans le brevet européen n° 0 681 621 et commercialisés sous la marque LOTUS®;
• des tampons C constitués de cent pour cent de fibres de coton, issus de nappes fabriquées suivant la demande de brevet européen n° 0 735 175 et commercialisés sous la marque DEMAK'UP®;
• des tampons D constitués de cent pour cent de fibres de coton, composée d'une nappe centrale non comprimée et de deux voiles de carde calandrés et marqués entourant la couche centrale .
• des tampons E comportant une nappe constituée d'une superposition de voiles de carde sur laquelle est déposé un nontissé hydrolié de fibres de viscose et de polyester, avant découpe ; et
• des tampons F constitués de 15 % de fibres thermofusibles et de 85 % de fibres de coton, ne présentant pas de couches différentes, ni de motif de surface.

Tensile strength was measured on the following buffers:

• buffers A according to the invention, consisting of one hundred percent cotton fibers;
• B stamps also consisting of one hundred percent cotton fibers, manufactured by the Applicant from webs described in European Patent No. 0 681 621 and marketed under the trademark LOTUS®;
• C buffers consisting of one hundred percent cotton fibers, derived from webs manufactured in accordance with European Patent Application No. 0 735 175 and marketed under the trademark DEMAK'UP®;
• D pads consisting of one hundred percent cotton fibers, consisting of an uncompressed central web and two calendered and marked card webs surrounding the central layer.
• tampons E comprising a web consisting of a superposition of card webs on which is deposited a nonwoven hydrolyzed viscose fiber and polyester, before cutting; and
• F pads consisting of 15% hot melt fibers and 85% cotton fibers, having no different layers or surface pattern.

Buffers B, C, D, E and F illustrate the state of the art.

The results corresponding to the averages of the measurements are reported in the Table below. AT B C D E F RT direction walk (N) 25 10 11 10 13 9 RT mean direction (N) 20 4 6 4 4 4

Tensile strengths in the forward direction and in the cross direction are very significantly higher for buffers A according to the invention compared to those of buffers B, C, D, E and F. This resistance is translated into use by an absence of deformation of the buffer.

The buffers according to the invention have a tensile strength in the operating direction of not less than 20 Newtons and a transverse tensile strength of not less than 15 Newtons.

It is also noted that for the buffers A according to the invention, the resistance to traction in the direction of the direction of travel is approaching the tensile strength in the running direction. The product according to the invention is homogeneous and advantageously has a certain symmetry with regard to the tensile strength and the deformation in the operating direction by relation to the meaning across. The product is called "square".

Elongation under a constant force of 5 Newtons was also measured using the same material as the tensile strength test.

The results (in percentage) are reported in the Table below and correspond to an elongation measured in the running direction. AT B C D E F Elongation under a force of 5 N (%) 1.42 3.16 1.84 6.4 3.9 0.98

The lower the elongation, the less the buffer will tend to deform at use.

It is observed that for buffers consisting of one hundred percent cotton, the buffers according to the invention have the lowest elongation.

Yet another essential feature of the buffer is the percentage of bound fibers compared to known hydrophilic cotton pads.

In the buffers according to the invention, at least 50% of the fibers are bound, from preferably 60%.

In order to illustrate the amount of bound fibers, the mass of bound fibers was measured on the surface of the buffer following the method below.

Disc-shaped pads of about 57 millimeters are used. diameter. Carefully separate the portion of the disc corresponding to the bound fibers by removing by hand all unbound fibers that come off without resistance. Then we weighs the remaining part of the disc. The mass measured corresponds to the quantity of fibers linked.

Measurements were made from buffer samples A, B, C, D summer.

The results are reported in the table below. AT B C D E Mass of bound fibers (g) 0.37 0.15 0.13 0.05-0.08 0.09 Corresponding weight 150 61 52 20-30 37

The amount of bound fibers in the buffer according to the invention is multiplied by two or even three in relation to the amount of bound fibers in the buffers of the art prior. For the first face, the surface fibers have at least one point of fixation in the thickness of the buffer. This allows to structure the first face of the stamp and give it a permanent relief.

This result is surprising and brings excellent cohesive properties to the tablecloth.

The cohesion of the buffer according to the invention is significantly improved compared with to the products of the prior art.

In order to illustrate this cohesion, the resistance to delamination of buffers A according to the invention as well as that of the buffers B, C, D and E corresponding to the state of the art. All these buffers are in the form of disc of about 57 millimeters in diameter.

• utiliser le même matériel que celui utilisé pour la mesure de la résistance à la traction, en remplaçant les mâchoires par des plateaux,
• placer un adhésif double-faces sur chacun des plateaux,
• déposer sur le plateau du bas, le disque de coton directement sur l'adhésif,
• presser les deux plateaux l'un contre l'autre,
• écarter les deux plateaux à une vitesse de 100 mm/min jusqu'à un écartement de 30 millimètres, et
• mesurer la force maximum exercée pour délaminer le disque.

The method of measuring the resistance to delamination consists of:

• use the same material used to measure tensile strength, replacing the jaws with trays,
• place a double-sided adhesive on each tray,
• place on the bottom shelf, the cotton disc directly on the adhesive,
• squeeze the two trays against each other,
• separate the two trays at a speed of 100 mm / min to a distance of 30 millimeters, and
• measure the maximum force exerted to delaminate the disc.

The results are reported in the Table below. AT B C D E F Resistance to delamination (N) 0.73 0.62 0.55 0.49 0.01 0.74

There is a clear improvement in the resistance to delamination for buffers according to the invention consisting of one hundred percent cotton fibers in relation to the delamination resistance of buffers B, C, D and E of the state of the art, made up of one hundred percent cotton fiber. The buffers A according to the invention, here made up of 100 per cent cotton fibers, are resistant to delamination similar to that of a product (buffer F) consisting of 15% of fibers hot melt and 85% cotton fiber.

In the case of the buffer E, the association between the web of card webs and the hydrolized sail and particularly weak.

The first face of the tampon according to the invention plush much less than some known products.

The linting resistance of the first side of the buffers A and buffers B, C, D, E and F of the state of the art following a method specific described below. The pads are disc shaped and have a diameter about 57 millimeters.

The method is to use a rubber finger mounted on a cylinder to simulate the friction on the skin. This finger is set in motion in order to come settle on the surface of a pad and move on its surface. We put the stamp in the form of a washer on a plate whose surface has a coating of Teflon. Then we fix this buffer by placing another plate on top, this last having a U-shaped cutout to let the finger pass, cutting showing part of the buffer. We adjust the number of passages of the finger, the speed, the load applied to the finger by means of a counterweight.

During the test, the finger comes to rest and move on the surface of the buffer five successive times. Fibers come off the surface of the pad and come press on the rubber finger. After the five passes, the fibers are recovered held by the finger with tweezers and placed on a glass of watch. The procedure is repeated for five buffers of each of types A, B, C, D, E and F. The fibers harvested from five buffers are weighed on a balance sensitive to tenth of a milligram. Each type of buffer A, B, C, D, E and F has been tested.

For the buffers A, the first external face A1 has been tested as well as the second outer face A2.

For the E buffers, the face corresponding to the hydrolied web E1 was tested as well than the other side E2.

Mass averages are reported in the Table below. A1 A2 B C D E1 E2 F Mass of fibers removed (10 ^-4 g) 5 50 50 50 30 3.5 480 55

The fiber mass is divided by 10 for the first face of the buffers according to the invention, with respect to the mass measured for the buffers B, C, D and F. The buffer E has a fluffy face due to the presence of the nonwoven but another face excessively fluffy compared to the second side of the pad according to the invention. Lint reduction is therefore very important for the buffer according to the invention. The mass of disc-shaped cotton pads commonly used varies between 0.5 and 0.7 grams. Fibers recovered from the first side (A1) of the five buffers A according to the invention therefore correspond to 0.1% of the mass of the buffer A. For comparison, the fibers recovered from the five buffers of each of the types B, C, D and F of the state of the art amount to 1% of the mass of corresponding buffers.

This result is unexpected and very advantageous.

The first face of the buffer therefore has a new structure, providing advantageous properties.

In fact, the buffer according to the invention has many advantages in use.

The first side is used to apply care products on the skin.

In the case of cleaning or removing make-up from the skin, apply the product cosmetic on the first side of the pad then we pass this first face on the skin or on the face.

Only one pass of the buffer is enough, it is no longer necessary to rub. This avoids irritations of the skin.

Indeed, the structure of the first face having striations form advantageously a relief in hollow and in bump. The surface in contact with the skin is more limited because of the relief.

The prominent hump portion increases pressure on the skin and forces friction. The friction effect thus obtained improves the cleaning. The hollow parts form an additional supply of available product.

During the passage of the tampon on the skin, the same hollow fills first for function that of product reservoir which is spread out in contact with the buffer on the skin, under application pressure, and then that of impurity collector at during the movement of the tampon on the skin. Cleaning is done by the first passage is thus optimized.

If the streaks are arranged in parallel lines, the displacement of the stamp on the skin is preferentially perpendicular to the streaks of the first side.

The second side is used to absorb impurities, excess product and traces of makeup that remain on the skin.

In use, the product does not deform, it has excellent handling.

In a particular example of use which is that of the removal of the varnish fingernail, the solvent which conventionally penetrates the buffer, is less absorbed in depth and is more easily restored when cleaning, thanks to the structure more compact of the first face of the buffer and the fibers tightened in the thickness of the buffer. The solvent is thus used more effectively to dissolve the varnish covering the nails.

Another effect was noted by the persons testing the buffer according to the invention.

The relief of the first face in contact with the skin has a massaging effect during passage of the tampon and provides a relaxing effect for the skin.

To improve the use of aqueous skin care products, such as toiletries, make-up and make-up products, the first outer face may include an agent delaying the absorption of these products to temporarily keep the products applied to the surface of the buffer without them penetrating inside the buffer.

The combination of the structure of the first face described previously with this new property delaying the absorption of aqueous products, provides a product very efficient in use.

The absorption retarding agent is a softener or waxes or a component that binds to the fibers.

Applied in small quantities to classically cotton products hydrophilic and absorbent, it has surprisingly been observed that these components allowed to delay the absorption of aqueous products at the surface of cotton products.

Examples of softeners are fatty amines, fatty alcohols, fatty esters, polyethylenes or fatty polyamides or mixtures thereof.

The components that bind to the fibers are, for example, metal salts stearic acid complexes, perfluorinated derivatives, zirconium salts or silicones.

The wax-based components are emulsions of waxes and paraffins or emulsions of waxes alone.

Preferably, the agent is a natural wax emulsion, of mineral origin, plant or animal.

Examples of wax of animal origin are spermaceti wax and wax bee.

Examples of vegetable wax are candelilla wax and wax carnauba.

Examples of wax of mineral origin are ceresin and azokerite.

The beeswax emulsion is particularly advantageous and suitable for the cosmetic use of the tampon. It is a dermatologically tested component. It's about a cationic emulsion of bleached beeswax which comprises beeswax, water, emulsifying agents, glyceryl stearate and diethanolaminoether stearate.

Beeswax itself is composed of esters of waxy fatty acids such as myricyl palmitate, cerotic acid and other homologous waxy acids and small amounts of hydrocarbons, cholesterol esters and ceric alcohols.

The absorption retarding agent is an emulsion or dispersion comprising at least one less than 30% of active ingredients.

The first side of the product or cotton pad according to the invention comprises at least 1 g / m ² of applied emulsion, that is to say at least 0.3 g / m ² of deposited active material.

The first face comprising on the surface such an agent acquires properties very advantageous.

It delays the penetration of aqueous products applied to the surface of buffers.

The penetration of skincare products such as milks, products makeup remover or makeup remover is a major disadvantage of cotton tampons conventional hydrophilic. Care products or cosmetics are wasted and are not used economically, they sometimes cross the buffer. The effectiveness of cleaning the skin is not optimized.

With such a treatment of the first face of the buffer, a "impermeability" water is created, this makes it possible to avoid the almost spontaneous absorption of aqueous products by the hydrophilic cotton fibers as soon as they are deposited on the pad.

A simple test highlighting this property is to deposit on the surface of a container filled with water, at room temperature (approximately 20 °), buffers treated according to the invention, the treated face being turned towards the outside and the face absorbent to water, and buffers B and C of the state of the art. The first ones stay on the surface for at least 5 minutes, the others are almost immersed instantaneously water and are very quickly immersed, usually after 3 to 5 seconds.

The advantage thus obtained is to be able to keep the products on the surface more long time and use the total amount of product deposited on the pad for the skin care, without loss of product and without deformation of the tampon.

A test of internal use to the plaintiff company was carried out by 25 people usually and exclusively using cotton wool C pads for skin care, make-up removal, etc.

Buffers A according to the invention, the first face of which has been treated by an agent retarding absorption, have been tested in comparison to buffers according to the invention the first face of which has not been treated and the C buffers of the state of the art.

The following observations were noted.

For buffers according to the invention, the first face of which has not been treated, 50% of people noted delayed absorption of skincare products surface of these buffers. This is explained by the specific structure of the first side buffers according to the invention. Indeed, the fibers are narrower in the thickness buffer.

As for the buffers according to the invention, the first face of which has been treated, almost all people: 92%, noted this ability of the delay pad absorption of care products.

50% of people also found an improvement in cleaning the using the buffers according to the invention, the first face of which has not been treated. With the buffers according to the invention, the first face of which has been treated, the number of people who found an improvement in cleaning, amounted to 92%.

Finally, for make-up removal, 50% of people observed better effectiveness of removing make-up with buffers according to the invention without treatment of the first face. 85% of people made this observation for tampons according to the invention with treatment of the first face.

Similar benefits have been observed in the use of makeup, such as lotions, creams, foundations, blushes, for apply and distribute the product on the skin.

People have also used the product advantageously according to the invention for applying perfumery products such as toilet waters. The immediate absorption of the eau de toilette by the buffer is avoided compared to the application of eau de toilette with cotton products of the prior art.

Two manufacturing techniques are possible to obtain the buffer according to the invention.

A first technique consists in differentiating the two faces of the buffer in hydrolizing each of the faces according to different parameters. A first method consists in making by layering at least two layers of fibers of cotton forming the two outer layers. These tablecloths can be of quality fibrous the same or different. They can be made directly from cotton hydrophilic and bleached. They can also be obtained from raw cotton ecru, then chemically treated to obtain hydrophilicity and bleaching. They are then superimposed and associated by any known means such as means of bonding or mechanical means such as calendering or needling. The means of association can still be hydraulic.

We can obtain a good association by impregnation of the tablecloths superimposed by any known conventional means such as bathing impregnation, spraying, spilling of a solution. This impregnation is associated with tableting compacting the tablecloth and eliminating some of the amount of liquid contained in the wet web, for example by calendering or passing on a vacuum slot.

A second method consists of preparing a sheet of cotton fibers by pneumatic and to arrange this sheet between two cotton carding sails. A method of manufacturing and association of continuous webs, is described by the patent No 0 681 621 in the name of the plaintiff.

In the latter case, the impregnation of the sheet surrounded by two sails carding, carried out during the various chemical treatments, contributes to the combination of layers between them.

The hydrolysis technique makes it possible to combine the layers or both layers between them, and to bind the surfaces of the tablecloth. We select parameters hydrolysis techniques for the first external face and use of parameters more classic hydrolysis for the other side. This allows by means of a single technique to fulfill three different functions: combination of layers or layers, binding of the fibers and differentiation of the two outer faces. Hydrolage is carried out at means of high-pressure water jets combined with vacuum voiding, by means of a device marketed by the company ICBT-PERFOJET, Grenoble, France.

The two hydrolysis stages, corresponding to the treatment of each of the two external faces of the product, can intervene, in the case of an unbleached fiber that will be chemically treated just after the impregnation step of the tablecloth as this is described in European Patent Application No. 0 735 175. They may also be placed in the final rinse phase according to European Patent No. 0 805 888 in the name of the plaintiff. The advantage here, whatever the process, is to differentiate the faces by hydrolysis, directly online.

The two outer faces are hydrolized according to different parameters one after another on endless cloths or cylinders.

High pressure water jets used to interlace the fibers of the faces external surfaces, mark the surface of these faces with streaks visible to the naked eye, the distance corresponds to the distance between the axes of the jets. More specifically, the hydrolysis device comprises a high pressure pump supplying an injector placed transversely to the scroll of the sheet or layer of fibers, over its entire width. The injector consists of a volume of water under pressure, closed by a blade of steel which is perforated with calibrated holes producing jets in the form of fines high pressure water needles projected perpendicular to the surface of the face external. These fine jets intermingle the fibers and cause the free fibers of the surface in the thickness of the product.

By changing the distance between the axes of the holes and the diameter of the holes and selecting a specific energy input for a hydrolysis device used for the treatment of an external face with respect to the other device used for the treatment of the other side, it differentiates the two outer faces of the product.

For the first external face, it is possible for example to use a hydrolysis device whose blade is perforated with a large distance between the holes: 1 to 5.5 millimeters, preferably between 2 and 4 mm. The holes perforated in the blade (commonly called "strip") have a diameter ranging from 130 to 200 microns and preferably from 140 to 170 microns and are regularly spaced. If the position of the injector is fixed and the layers of cotton scrolling under the latter, there is observed on the surface of the product, a series of grooves or parallel grooves corresponding to the passage under the jets. The pressure exerted is high, at least 40 bar, preferably between 50 and 80 bar so as to deeply dig grooves or grooves in the product. These striations result from the compression, the drive and the fixation of the fibers in the thickness of the sheet. For the realization of the streaks, the energy input is at least 1.4 x 10 ^-3 kwh / m ² and can vary between 1.4 x 10 ^-3 and 2.5 x 10 ^-3 kwh / m ² depending on the speed, the pressure, the diameter of the holes and the spacing between the holes.

By changing the position of the injector or by moving or vibrating the blade, different streak geometries can be obtained (FIG. 4A for example). It is also possible to place masks under the blade closing some holes following a specific geometry in order to obtain a distribution of striations such as that shown in Figure 4C.

The first face thus hydrolized has a compacted appearance, very "structured", reliefs hollow and hump. The surface condition thus obtained, does not fluff at all.

For the second external face, a hydrolysis device using classic parameters, with a perforated blade of holes spaced a distance between 0.4 and 1.2 mm and preferably between 0.4 and 0.9 mm. The diameter of holes can range from 100 to 130 μm.

The pressures exerted for speeds similar to those used for the treatment of the first face, are moderate: from 20 to 40 bars. This corresponds to an energy input of between 0.9 x 10 ^-3 and 1.6 x 10 ^-3 kwh / m ² .

The streaks obtained on the surface of the second face are much thinner and shallow. The second outer face has a less compacted appearance, a soft and absorbent surface. It does not have visible reliefs with the naked eye, in hollow and hump.

The two faces thus obtained have fundamentally different aspects.

Additional differentiation can be made by printing by marking different patterns of existing streaks on the first side.

A second technique for manufacturing the buffer according to the invention consists of differentiate the two faces of the buffer by marking.

Two slicks are prepared from bleached fibers tableted or bleached tablecloths. They are then each marked by passing between a cylinder engraved with a raised pattern and a smooth counterpart to print this pattern in the thickness of the sheet and form a relief in hollow and humped more or less deep on the surface of the plies which will correspond to the external faces of the buffer. The marking pressures exerted by the cylinders are sufficient to obtain the resistances expected for the buffer, that is to say a resistance of at least 20 N in direction and at least 16 N in the cross direction, as measured by the method of test described previously.

Tablecloths may contain synthetic hot melt fibers. They are compressed by means of heated calenders which leads to the binding of the fibers by melting of the hot melt fibers and improves cohesion.

The first sheet can be marked by means of a cylinder which can for example, have parallel strips in relief, perpendicular to the axis of the cylinder, forming parallel striations on the surface of the product, these strips being spaced apart a distance of between 1 and 8 mm, preferably between 2 and 4 mm. The height bands corresponding to the depth of the streaks is at least 0.25 mm and preferably at least 0.50 mm.

The second face may be marked by means of a cylinder example of the parallel bands in relief, perpendicular to the axis of the cylinder, spaced apart from each other by a distance of between 0.8 and 1.2 mm. The height of bands is less than 0.25 mm.

By the marking technique, any geometry and distribution of the streaks can should be considered, in particular for the surface of the first layer to form a embossed relief and bump at the first face.

An example of a pattern made by marking is illustrated in FIG. 4D. The circles corresponding to the printed pattern form cavities or cavities on the surface of the buffer.

According to another embodiment, the second face may be calendered without marking or consolidated by any other known means such as hydrolysis, binder spray, the heating of hot melt fibers if the latter are present.

The two tablecloths thus and marked and / or consolidated, are superimposed of such that the marked and / or consolidated surfaces are located outside. They are associated for example by gluing with starch.

During the manufacture of the product, intended to become the buffer according to the invention, the first external surface is treated in such a way as to delay the absorption of the products aqueous (care products, ...) for a cosmetic use of tampons.

After the impregnation steps, and before or after drying, this first face is treated by applying an agent delaying the absorption of aqueous products, previously described. For example, a wax emulsion is applied in an amount of at least 1 g / m ² , which amounts to depositing at least 0.3 g / m ² of active material (waxes).

This surface treatment is done by any conventional means, such as spraying by means of nozzles, coating by means of a cylinder, rotogravure printing ...

The products thus manufactured, having different faces, are then cut into sizes and packaged in flexible packaging or sachets.

It is interesting to note that due to the new structure of the first side buffer and its surface condition, the stacked buffers are more easily isolated each other. It is thus much easier for the user to extract the buffers one by one from the package once the pre-cut operculum has been torn releasing the opening of the packaging.

Claims (18)

1. Hydrophilic cotton pad for skin-care, having a grammage of at least 150 g/m², having two different outer sides the fibres of which are bound, characterized in that the first outer side comprises hollow grooves with a spacing e₁ between the grooves of between 1 and 8 mm and a groove depth p of at least 0.25 mm and in that the tensile strength of the pad is at least 20 N in the machine direction and at least 16 N in the cross direction, according to the test method given in the description.
2. Hydrophilic cotton pad for skin-care, having a grammage of at least 150 g/m², having two different outer sides the fibres of which are bound, characterized in that the first outer side comprises hollow grooves with a spacing e₁ between the grooves of between 1 and 8 mm and a groove depth p of at least 0.25 mm and in that at least 50 per cent of the fibres of the pad are bound.
3. Pad according to claim 1 or 2, characterized in that the spacing e₁ between the grooves of the first side lies between 1.2 and 5.5 mm and preferably between 2 and 4 mm.
4. Pad according to one of the preceding claims, characterized in that the depth of the grooves of the first side is at least 0.40 mm and preferably at least 0.50 mm.
5. Pad according to one of the preceding claims, characterized in that the tensile strength of the pad is at least 25 N in the machine direction and at least 20 N in the cross direction, according to the test method given in the description.
6. Pad according to one of the preceding claims, characterized in that the second outer side comprises grooves with a spacing e₂ between the grooves of between 0.4 and 1.2 mm.
7. Pad according to one of the preceding claims, characterized in that at least 60 per cent of the fibres of the pad are bound.
8. Pad according to one of the preceding claims, characterized in that the grooves of the first side form continuous or discontinuous, straight, broken or curved lines in the surface of the pad.
9. Pad according to one of the preceding claims, characterized in that it consists of one hundred per cent cotton fibres.
10. Pad according to one of the preceding claims, characterized in that the bound fibres are hydroentangled.
11. Pad according to one of the preceding claims, characterized in that one of the outer sides of the pad additionally comprises an imprint distinct from the aforementioned grooves.
12. Pad according to one of the preceding claims, characterized in that the first outer side comprises an agent retarding the absorption of aqueous products such as cosmetic products, products for removing make-up or make-up products.
13. Pad according to claim 12, characterized in that the agent retarding the absorption of aqueous products is a composition based on softeners, waxes, or a component attaching to the fibres.
14. Pad according to claim 13, characterized in that the agent retarding the absorption of aqueous products is an emulsion of a natural wax of mineral, vegetable or animal origin, preferably an emulsion of beeswax.
15. Method for producing an hydrophilic cotton pad according to one of claims 1 to 10, characterized in that it consists of providing a cotton web, of hydroentangling a first outer side of the web by means of water jets of which the axes are separated from each other by a distance of between 1 and 5.5 mm with an energy input of at least 1.4 x 10^-3 kwh/m², and of hydroentangling the other outer side of the pad by means of water jets of which the axes are separated from each other by a distance of between 0.4 and 1.2 mm with an energy input of at least 0.9 x 10^-3 kwh/m².
16. Method for producing a pad according to one of claims 1 to 9, characterized in that it consists of providing at least two hydrophilic cotton webs from bleached fibres put into a web or from bleached webs, of marking the first web so as to print grooves having a spacing between the grooves of between 1 and 8 mm and a depth of at least 0.25 mm on one side of the first web, the marking pressure being sufficient to obtain a strength of the pad of at least 20 N in the machine direction and 16 N in the cross direction according to the test method given in the description, of marking and consolidating the second web, and of combining the two webs obtained in this way, the two marked and/or consolidated sides being situated on the outside of the pad.
17. Method for producing a pad according to one of claims 12 to 14, characterized in that it consists of carrying out the steps of the method according to claim 15 or 16 and of applying an agent retarding the absorption of aqueous products, for example by spraying, onto the first outer side of the pad.
18. Use of a pad according to one of claims 1 to 14 for skin-care, in particular for removing make-up, characterized in that the first outer side is used for cleansing the skin by applying a product for removing make-up or a toiletry milk, the grooves constituting first of all a reservoir for the products and then a collector for impurities for the same pass, and the second outer side is used for absorbing the excess of the product and impurities.

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