The present invention relates to a device for the application of a cosmetic product, of the type comprising a nonwoven body formed on the basis of fibres, all of the fibres forming the nonwoven body being cellulose fibres.

Such an application device is to form, for example, a wipe, a web, a fabric, a patch, a disc, or a square which is to be impregnated with the cosmetic product with a view to the application of that product by bringing the impregnated device into contact with the skin, the nails or the keratin fibres of a user. In a variant, the application device is arranged at one end of a gripping body which is to be grasped by the hand of a user in order to permit the application of the cosmetic product to the user.

"Cosmetic product" means, in particular, a product such as defined in Council

Directive 93/35/EEC dated 14th June 1993. The cosmetic product is, for example, make- up, a make-up-removal composition which is to remove make-up applied to the skin or to the keratin fibres of a user, a nail varnish remover or, more generally, a cream or an emulsion.

WO 2007/070147 discloses a wipe comprising a nonwoven body. The nonwoven body of the wipe is, for example, produced on the basis of a mixture of cellulose fibres which is formed into a sheet by a wet process similar to the formation of paper.

Synthetic fibres not derived from cellulose are added to the fibre mixture in order to modify the properties of the wipes.

Current environmental constraints mean that that type of wipe must be rapidly biodegradable in order to limit the amount of waste resulting from the increasing use of those products.

However, it is still necessary to maintain appropriate properties for wipes, in particular as regards their external appearance and, in particular, their gloss, and as regards their properties of use and, in particular, their mechanical strength.

An object of the invention is therefore to obtain a device for the application of a cosmetic product, which device is substantially biodegradable, while at the same time having an improved aesthetic appearance and a high mechanical strength.

To that end, the invention relates to a device of the above-mentioned type, characterised in that the fibres forming the nonwoven body comprise at least 20% by mass of bamboo fibres relative to the total mass of the fibres forming the nonwoven body. The device according to the invention may comprise one or more of the following features, taken in isolation or in accordance with any technically possible combination:

- the fibres forming the nonwoven body comprise from 38% by mass to 100% by mass of bamboo fibres, relative to the total mass of the fibres forming the nonwoven body; - the fibres forming the nonwoven body comprise from 38% by mass to 70% by mass, advantageously from 38% by mass to 50% by mass or from 60% by mass to 70% by mass, or comprise from 80% by mass to 100% by mass, advantageously from 92% by mass to 100% by mass of bamboo fibres, relative to the total mass of the fibres forming the nonwoven body; - the average length of the bamboo fibres is greater than 5 mm, and is advantageously from 10 mm to 60 mm;

- the nonwoven body is formed on the basis of a mixture of cellulose fibres, the mixture of cellulose fibres comprising bamboo fibres and cellulose fibres other than bamboo; - the cellulose fibres other than bamboo are selected from viscose fibres, lyocell fibres and mixtures thereof;

- the average length of the cellulose fibres other than bamboo is from 15 mm to 50 mm, advantageously from 30 mm to 50 mm;

- all of the cellulose fibres of the nonwoven body are bamboo fibres; and - the nonwoven body is a sheet deformable to the touch.

The invention relates also to a method for the manufacture of a device as defined above, the method comprising the following steps:

- providing cellulose fibres, the cellulose fibres comprising at least 20% by mass of bamboo fibres relative to the total mass of the cellulose fibres; - physical, chemical and/or mechanical bonding of the cellulose fibres in order to form a fibre-based nonwoven body, all of the fibres forming the nonwoven body being cellulose fibres.

The invention will be better understood on reading the following description which is given purely by way of example and with reference to the appended drawing in which Figure 1 is a top view of a wipe for the application of a cosmetic product according to the invention.

Figure 1 illustrates a first embodiment of an application device 10 according to the invention.

Such an application device is to form a wipe, a web, a fabric, a patch, a disc or a square which is to be impregnated with the cosmetic product with a view to the application of that product by bringing the impregnated device into contact with the skin, the keratin fibres or the nails of a user.

In the embodiment shown in Figure 1 , the device 10 is a wipe for the application of the cosmetic product. The device 10 comprises a nonwoven body 12 produced on the basis of a mixture of bamboo fibres 14 and cellulose fibres 16 other than bamboo.

In a variant, the nonwoven body 12 is formed exclusively from bamboo fibres. The body 12 is advantageously a sheet. In the context of the present invention, "sheet" means a body which is substantially flat, that is to say, which has a thickness at least twice as small, advantageously at least five times as small, as its other dimensions. The thickness of the body 12 is advantageously from 0.3 mm to 3 mm.

In the embodiment shown in Figure 1 , the body 12 is substantially rectangular. The maximum surface area of the body 12 is less than 1 m ² .

The body 12 is supple so that it is deformable to the touch. In the context of the present invention, "deformable to the touch" means that a user of the application device 10 can deform the body 12 by means of her fingers, in particular by pinching it between two fingers.

The body 12 is a nonwoven produced on the basis of a mixture of the fibres 14 and 16 which are all cellulose fibres. In the context of the present invention, "nonwoven" means a substrate comprising the mixture of fibres, in which substrate the individual fibres or the filaments are arranged in a disordered manner in a structure in the form of a batt and are neither woven, nor knitted. The nonwoven fibres of the body are generally bonded to each other, under the effect of either a mechanical action (water jet) or a thermal action, or by the addition of a binder.

Such a nonwoven is defined, for example, in the standard ISO 9092 as a web or batt of directionally or randomly orientated fibres, bonded by friction and/or cohesion and/or adhesion, excluding paper and products which are woven, knitted, tufted, stitch-bonded.

As will be seen hereinafter, the nonwoven bodies 12 in the context of the present invention are generally obtained by a dry process, in particular by carding or by a process of aerodynamic deposition referred to as "airlaid". In a variant, the nonwoven bodies 12 of the invention are obtained by a wet process in a procedure similar to the production of paper.

"Cellulose fibres" means fibres based on natural cellulose, that is to say, fibres originating directly from a plant, either by being harvested from the plant, or by being obtained by mechanical treatment of the plant, such as grinding, pressing, crushing and/or separation. "Cellulose fibres" also means fibres of modified cellulose, that is to say, natural cellulose or solubilised natural cellulose, which has reacted with a chemical component. "Cellulose fibres" additionally means fibres of regenerated cellulose, that is to say, optionally modified natural cellulose, which are solubilised in a solvent and then reformed in the form of fibres.

Those cellulose fibres are advantageously biodegradable.

Those cellulose fibres contain at least 50% cellulose or cellulose derivative.

Thus, the fibres of the nonwoven body 12 do not contain synthetic fibres. "Synthetic fibres" means fibres which do not have a natural precursor polymer, such as fibres obtained by polymerisation of a synthetic monomer, for example derived from petroleum.

Synthetic fibres include, in particular, polyolefins, such as polyethylene or polypropylene, polyesters, such as polyethylene terephthalate, polyamides, such as nylon, fluorinated or chlorinated polymers, such as polyvinyl chloride. Such fibres are not biodegradable and can therefore not be used to produce the nonwoven body 12 of the application devices 10 according to the invention.

The bamboo fibres 14 of the nonwoven body 12 are obtained from the plant called "Bambuseae" of the "Poaceae" family.

The bamboo fibres 14 are advantageously obtained from regenerated bamboo cellulose. For that purpose, the method for the production of the bamboo fibres comprises the mechanical cutting of the harvested bamboo to obtain chips, screening, then a washing of the chips so formed, cooking, bleaching, beating, followed by etiolation.

The operation then comprises filtration, spinning to obtain fibres, and a step of cutting the fibres, followed by drying. Such a method is described, for example, in Chinese patent application CN1458306.

The fibres obtained then advantageously have an average length which is greater than 5 mm and which is especially from 5 mm to 50 mm, advantageously from 30 mm to 50 mm, and which is especially substantially equal to 38 mm.

The fibres 14 have a diameter of from 5 μm to 30 μm and a titre of from 1.2 dtex to 1.7 dtex.

The bamboo fibres 14 have a density which is from 1.2 to 1.4 and which is substantially equal to 1.3. They have a moisture content which is from 5% by mass to 15% by mass, and which is advantageously substantially equal to 12%.

Those bamboo fibres 14 have an elongation at break of from 10% to 25% in the dry state, advantageously from 20% to 25%. The bamboo fibres 14 have a tenacity which is from 2 to 4 cN/dtex, and which is preferably substantially equal to 2.2 cN/dtex.

The bamboo fibres 14 have a deep white colour. When a nonwoven containing exclusively bamboo fibres 14 is produced, it thus has a lightness "L" of from 85 to 92, a component "a" of from - 0 to - 2, and a component "b" of from 2 to 5, as measured in the

"L ^* a ^* b" colour representation model developed by the International Commission on

Illumination, according to the standard CIE 1976.

The solubility of the bamboo fibres 14 after 30 minutes' immersion in a solution containing 55.5% standard sulphuric acid at 2O ⁰ C is greater than 25%, advantageously greater than 30%, and is especially substantially equal to 32%.

The roundness of the bamboo fibres may also be less than 50% and especially substantially equal to 40%.

Relative to the total mass of the bamboo fibres 14 and the cellulose fibres other than bamboo 16, the proportion by mass of bamboo fibres in the mixture of bamboo fibres 14 and cellulose fibres other than bamboo 16 of the nonwoven body 12 is from 20% by mass to 100% by mass, advantageously from 38% by mass to 100% by mass.

Advantageously, that proportion by mass is from 38% by mass to 70% by mass, advantageously from 38% by mass to 50% by mass or from 58% by mass to 70% by mass, or is from 80% by mass to 100% by mass, advantageously from 92% by mass to 99% by mass.

The bamboo fibres are marketed, for example, by the Chinese company TANGSHAN SANYOU under the reference (1.6 dtex ^* 38 mm, bamboo fibers, bright) or by the Chinese company BAMBRO TEX under the name 1.56 dtex.

The cellulose fibres other than bamboo 16 are obtained on the basis of natural cellulose fibres of plant origin, man-made cellulose fibres obtained on the basis of modified and/or regenerated cellulose or mixtures thereof.

Examples of natural cellulose fibres of plant origin are cotton, hemp, jute, wool, or wood pulp.

Man-made cellulose fibres are obtained by a process of treating natural cellulose. Those fibres are defined, for example, in a generic manner by the International

Bureau for the Standardization of Man-made Fibres (BISFA) as being cellulose fibres of the "acetate" or "triacetate" type obtained by acetylation of the hydroxyl groups of cellulose, fibres of the "alginate" type obtained from the metal salts of alginic acid, such as, for example, the alkali metal or alkaline-earth metal salts of alginic acid, such as calcium alginate, or cellulose-based fibres of the "cupro" type obtained by the "cuprammonium" process, in which the natural cellulose is dissolved in a compound comprising copper and an amine, such as cupratetraamine dihydroxide.

Advantageously, the cellulose fibres other than bamboo 16 are viscose fibres. In the context of the present invention, "viscose fibres" means fibres obtained by the "viscose" process according to the definition of the BISFA, in which, advantageously, a basic solution of cellulose xanthate is drawn in the form of fibres from one or more regeneration baths. Those fibres sometimes have a great rupture strength and are then described as "modal".

Advantageously, and in a variant, the cellulose fibres other than bamboo 16 are lyocell fibres. "Lyocell fibres" means cellulose fibres obtained by a spinning process from an organic solvent which comprises a mixture of organic chemical products and water, the expression "spinning by solvent" meaning the dissolving of the cellulose in the solvent without the formation of a cellulose derivative.

In that process, which the BISFA describes as the "lyocell" process, the natural cellulose is, for example, dissolved in a mixture of water and an amine-N-oxide, for example a tertiary amine-N-oxide, such as N-methylmorpholine-N-oxide, and is extruded through an air passage into a precipitation bath in order to form fibres. Such a process is described, for example, in FR 2 450 293.

The cellulose fibres other than bamboo 16 so obtained have a length which is from 10 mm to 50 mm, advantageously from 30 mm to 50 mm, and which is substantially equal to 40 mm. The fibres 16 have a diameter of from 5 μm to 30 μm.

They have a linear density of from 1.5 dtex to 2.0 dtex and a tenacity at break of from 20 cN/tex to 40 cN/tex, advantageously from 16 to 34 cN/tex, as measured by the standards. They also have an elongation at break, measured by the standard, of from 8% to 25%.

A nonwoven formed exclusively from fibres 16 has a lightness "L" greater than 91 %, and the components "a" and "b" are from 0 to 1 and from -3 to -2, respectively, as measured in the "L ^* a ^* b" colour representation model developed by the International

Commission for Illumination, according to the standard CIE 1976. The cellulose fibres other than bamboo 16 are therefore white.

Relative to the total mass of the fibres 14, 16 making up the body 12, the proportion by mass of cellulose fibres other than bamboo 16 is from 0% by mass to 80% by mass, advantageously from 0% to 62% by mass.

Advantageously, that proportion is from 30% by mass to 62% by mass, advantageously from 50% by mass to 62% by mass or from 30% by mass to 42% by mass, or is from 0% by mass to 20% by mass, advantageously from 1% by mass to 8% by mass.

The sum of the percentage by mass of the bamboo fibres 14 and of the percentage by mass of the cellulose fibres other than bamboo 16 is equal to 100%. Advantageously, the fibres 16 are produced on the basis of viscose or lyocell fibres which are marketed by the Austrian company LENZING under the respective trademarks "LENZING VISCOSE®" and "LENZING LYOCELL®".

Advantageously, a chemical binder is not used to maintain the mechanical cohesion of the nonwoven body 12. In a variant, a chemical binder is used. That binder is, for example, an acrylic emulsion, an emulsion of the vinyl acetate-ethylene type, an emulsion of the styrene- butadiene-styrene type, or a vinyl chloride emulsion.

As illustrated by Figure 1 , the nonwoven body 12 of the device 10 thus has an external surface in which the bamboo fibres 14 are visible, being dispersed in a homogeneous manner in the structure of the cellulose fibres other than bamboo 16, which gives the application device 10 a natural external appearance.

The body 12 has, relative to a nonwoven formed exclusively from cellulose fibres 16 as defined above, a coefficient ΔE greater than 2, as defined by the following equation:

ΔE = _Λ /(L ₁ -L ₂ ) ² + (a ₁ -a ₂ ) ² + (b ₁ -b ₂ ) ² where L ₁ , a-i and b-i are the "L ^* a ^* b" coefficients of the nonwoven body 12 and L ₂ , a ₂ and b ₂ are the "L ^* a ^* b" coefficients of a nonwoven produced exclusively on the basis of fibres 16.

The body so obtained has a basis weight of from 40 to 250 g/m ² . The nonwoven body 12 of the application device is advantageously charged with at least one cosmetic product, such as make-up, a make-up-removal composition, a nail varnish remover, or more generally with a cream, an emulsion or a lotion.

That charging can be carried out in the factory, after the manufacture of the body 12, before the device 10 is used by the user, the device 10 charged with cosmetic product then being placed in packaging in order to be supplied to the user. In a variant, the nonwoven body 12 may be free from cosmetic product before it is used by the user, the user herself applying the cosmetic product to the nonwoven body 12 when it is put to use.

Examples of methods for the manufacture of an application device 10 according to the invention will now be described. Initially, bamboo fibres 14 such as described above and cellulose fibres other than bamboo 16 such as described above are provided and are mixed to obtain a substantially homogeneous mixture of fibres 14 and fibres 16.

The method then comprises a step of forming the nonwoven body 12, a step of consolidating the body 12, and then a finishing step.

The step of forming the body 12 is carried out either by the dry process or by the wet process, those processes being referred to by the terms "drylaid" and "wetlaid", respectively.

In the dry process, the body 12 is advantageously formed by carding or by a process of aerodynamic deposition referred to as "airlaid".

For the carding operation, bales of fibres 14, 16 are first of all opened, then mixed and brought to a carding machine by means of a conveyor belt so that the fibres 14, 16 are combed, individualised, and orientated in accordance with a general axis.

The fibres 14, 16 of the nonwoven body 12 obtained by carding are deposited on a main drum substantially parallel with each other in the direction of the machine.

In the process of aerodynamic deposition, a carding machine is used to form a mat of fibres 14, 16 which is brought to a rotating roller. Under the action of a centrifugal force, the batt of fibres 14, 16 is projected into a current of air in which the fibres lose all preferential direction, in order then to settle on a forming belt. In the wet process, a very dilute paste containing the fibres 14, 16 is deposited on a conveyor belt. The water is then removed from the belt by suction to dehydrate and form the body 12. The body 12 is then consolidated by compression between cylinders, and then dried.

The fibres 14, 16 obtained in the body 12 so formed have very variable orientations. In the consolidation step, various types of bonding are used to ensure mechanical cohesion of the body 12.

Advantageously, mechanical bonding is used to consolidate the body 12. A first type of mechanical bonding is needle-punching, in which needles, which are advantageously barbed, are punched vertically through the fibres 14, 16 of the body 12, which brings about the interlacing thereof. That technique enables nonwovens having a great basis weight and thickness to be obtained.

Advantageously, the bonding is carried out by jets of water in accordance with the technique referred to as "spunlacing" or "water-jet consolidation".

In that process, the fibres 14, 16 of the body 12 are interlaced by means of high- pressure water jets. When in contact with those jets, the fibres are rearranged in the three dimensions of the body 12 and consolidation can be obtained without adding a binder. The pressure of the jets, which is, for example, from 50 bar to 200 bar, determines the strength of the nonwoven which it is desired to obtain.

In a variant, thermal bonding is used by compressing the body 12 between two cylinders in order to fuse the fibres 14, 16 to each other at high speed. A controlled flow of hot air or ultrasound may also be used to produce bonds between the fibres 14, 16.

In a variant, chemical bonding is carried out by applying to the body 12 a binding agent advantageously formed by an acrylic emulsion, an emulsion of vinyl acetate- ethylene, an emulsion of styrene-butadiene-styrene, or another dispersed polymer.

Those binders are applied uniformly by impregnation, coating or spraying, either intermittently or continuously.

In the finishing step, chemical substances may be added after the consolidation of the body 12. Mechanical embossing processes may be used, in particular, to create designs on the body 12.

Three examples of wipes according to the invention, produced on the basis of a mixture of viscose fibres and bamboo fibres or on the exclusive basis of bamboo fibres, and a comparative example of a wipe produced exclusively from viscose fibres will now be described in Table 1 below.

TABLE 1

TABLE 2

The wipes are manufactured by a dry process and are consolidated by water jets. No binder is added to consolidate the nonwoven body.

The results of colorimetry by the L ^* a ^* b method are set out in Table 2 to illustrate the natural appearance of the wipes according to the invention.

The gloss results of the wipes manufactured are set out in Table 3 to illustrate the increase in gloss observed with the application devices according to the invention.

TABLE 3

The gloss is quantified by means of a reflectometer which measures the intensity of the light reflected in a narrow range of angles of reflection on the surface to be measured. The measurement results of the reflectometer are based on a comparison with the amount of light measured on a polished black glass standard having a defined refractive index. For that established standard, the value of the measurement is fixed at 100 gloss units. The results presented in Table 3 were obtained with the "micro-Tri-Gloss" apparatus manufactured by the company BYK GARDENER. Those results are obtained, in particular, in accordance with the standard DIN EN ISO 2813.

As will be appreciated, the presence of bamboo fibres improves the gloss, in particular at an angle of illumination of 85°. The external appearance of the application devices 10 according to the invention is improved thereby.

In addition, the tensile strength of the devices 10 according to the invention was measured. The results are summarised in Table 4 below.

TABLE 4

The tests are carried out in accordance with the EDANA method using five rectangular test pieces having the dimensions (250 +/- 0.5 mm) x (50 +/- 0.5 mm) for each of the following conditions in the machine direction and in the transverse direction. The test pieces are kept in a desiccator at 2O ⁰ C and at 65% relative humidity. The time lapse between removal from the desiccator and the test does not exceed 30 minutes. In order to obtain 65% relative humidity, a saturated solution of ammonium nitrate salt (NH ₄ NO ₃ ) is poured into the bottom of the desiccator, or a climate chamber is regulated at a temperature of 25 ⁰ C and at a hygrometry of 65% relative humidity.

The test pieces are placed under tensile preload. During the preloading, the speed is 1 mm/minute and the force applied is 0.1 Newton. Once the preload has been reached, the test starts. The test speed is 100 mm per minute and the distance between the jaws is 200 mm.

The rate of absorption, namely the amount of liquid retained by a sample of the device 10 according to the invention after defined immersion and draining times is summarised in Table 5 below.

TABLE 5

Those results are obtained for each sample on the basis of five rectangular test pieces per sample of the device 10 according to the invention, spaced by at least 10 cm over the width, having dimensions (100 mm +/- mm) x (100 mm +/- 1 mm). The samples to be tested are conditioned for 24 hours in a climate chamber at 2O ⁰ C and at 65% relative humidity. A crystalliser containing municipal water to a level of approximately 20 mm is placed in the test room two hours before the test so that the temperatures of the municipal water and of the room are in equilibrium. The samples are then removed from the climate chamber, and are weighed individually or in a group and are subsequently placed on a wire mesh measuring 120 mm x 120 mm with a mesh size of 2 mm. The wire mesh is immersed in the water, avoiding the introduction of air bubbles, for 60 seconds and is then lifted out of the container by tongs. Each sample is then drained vertically for 120 seconds before being placed in a covered glass container. The whole is then weighed to obtain the rate of liquid absorption.

The presence of bamboo fibres does not affect the absorption capacity of the devices 10 according to the invention. The anti-bacterial activity of the devices 10 according to the invention is measured in Table 6 below.

TABLE 6

That activity is measured in accordance with the standard NF EN ISO 20743 of

2007, by comparison with a control formed from cotton. The strain used is Staphylococcus aureus ATCC 6538. The inoculation suspension comprises 1.02 x 10 ⁵ CFU/ml where the term CFU denotes "Colony Forming Units".

The results are measured on three identical samples in order to determine the average of the logarithm of the colony forming units per test piece (CFU/tp).

As illustrated by Table 6, the devices according to the invention have a bacteriostatic activity compared with the cotton control.

In a variant (not shown), the application device 10 is arranged at a free end of a gripping device to form a tool for applying a cosmetic product to a user, for example to the keratin fibres of a user.

As indicated above, the bamboo fibres 14 have a length of from 5 mm to 50 mm and the cellulose fibres other than bamboo 16 have a length of from 10 mm to 50 mm.

Advantageously, the quotient of the average length of the bamboo fibres 14 to the average length of the cellulose fibres other than bamboo 16 is from 0.9 to 1.1. Likewise, as indicated above, the bamboo fibres 14 have an average diameter of from 5 micrometres to 30 micrometres and the cellulose fibres other than bamboo 16 have a diameter of from 5 micrometres to 30 micrometres.

Advantageously, the quotient of the average diameter of the bamboo fibres 14 to the average diameter of the cellulose fibres other than bamboo 16 is from 0.9 to 1.1. The choice of those quotients of average lengths and/or average diameters facilitates the manufacture of the nonwoven body 12. In addition, when such quotients are selected, the tear strength of the nonwoven body 12 constituting the device 10 is increased.