LU101061B1 - Process for improving the gloss of compositions for nail varnish - Google Patents

Abstract

The invention relates to a method for improving the gloss, transparency, luster and / or stability time of a composition for nail varnish comprising insoluble or particulate solid components, selected from a transparent base nail polish, a thixotropic nail polish base and / or a pigmented nail polish base, said method comprising subjecting said nail polish composition to a sequence of two or more grinding steps selected from ( A) grinding in a horizontal linear ball mill, (B) grinding in a vertical linear ball mill, (C) grinding in a high pressure mill, (D) grinding in a basket ball mill, ( E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step chosen from (A) or (B) and at least one step (C). The invention also relates to the use of a combination of grinding steps.

Description

PROCESS FOR IMPROVING THE BRILLIANCE OF COMPOSITIONS FOR

NAIL POLISH Technical area

The present invention relates to a method of improving the gloss, transparency, luster and stability of cosmetic compositions for nail varnish. State of the art

[0002] The different properties that are required of a nail varnish are generally the following: e Good application capacity, with a brush of the appropriate size and shape. The brush provides a smooth, streak-free surface with a constant thickness in order to obtain a homogeneous film and coloring.

e An appropriate drying time of the order of a few minutes.

e Durability over time which is defined by the hold, avoiding chipping of the varnish or its wear at the nail tip.

e High shine on application, ie a few minutes after drying, and shine retention over time, ie shine that decreases as little as possible in the days following application.

e Good stability of the nail varnish composition before use and therefore a sufficient shelf life.

[0003] In particular as regards the shine, this is generally provided by the various non-volatile constituents of the nail varnish, such as resins or nitrocellulose. However, this parameter is strongly affected by the fact that these compounds are optionally introduced into the formulations in solid form which is hardly soluble. Still other ingredients are solid, insoluble, possibly particulate, components which will remain suspended in the formulations. Among these insoluble solid components, mention will be made in particular of pigments, clays, etc. which, by virtue of their physicochemical characteristics, lead to a reduction in gloss compared to the same formulation which does not contain them. Despite the different processes involved in the preparation of these components, a decrease in gloss is clearly noted. The various steps implemented in the preparation of these components before their use in nail varnish compositions allow several actions. These actions can be as follows: e A wetting action, which moves and eliminates air or moisture that is on the surface of these solid components.

e A grinding action which breaks down: o agglomerates; agglomerates correspond to the association of primary structures by surface contacts.

o aggregates; the aggregates rather correspond to a secondary structure originating from the association of the primary structures by edge-to-edge contacts.

e A dispersing action, which corresponds more particularly to the homogeneous distribution of the primary particles in order to avoid the reformation of the secondary structures.

To these different actions on these solid or particulate components, is added the use of additional ingredients used in small quantities but whose percentage of use depends directly on the nature (organic or not) of the solid or particulate components. to formulate. These additional ingredients, called wetting or dispersing agents, generally have bifunctional structures. One of the functions, having a strong affinity for the surface of solid or particulate components, orients towards the latter and binds to it by chemical bonds or bonds of lower energy of the Van der Waals type. The second function is oriented towards the continuous phase, generally composed of solvents and resins.

[0005] Even though these different angles of action for increasing gloss are known in the art, it remains generally desirable to improve the gloss of formulations comprising solid or particulate components and to increase their stability.

Object of the invention

[0006] An object of the present invention is therefore to provide a solution for increasing both the gloss and the stability of nail varnish compositions containing solid components which are poorly or insoluble or particulate.

General description of the invention

In order to achieve the objective mentioned above, the present invention provides a process for improving the gloss, transparency, luster and / or the stability time of a composition for varnish. nails comprising hardly soluble, insoluble or particulate solid components, selected from a transparent nail polish base, a thixotropic nail varnish base and / or a pigmented nail varnish base, said method comprising subjecting said composition to nail polish in a sequence of two or more grinding steps selected from (A) grinding in a horizontal linear ball mill, (B) grinding in a vertical linear ball mill, (C) grinding in a high pressure mill, (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step selected from (A ) or (B) and at least s a step (C).

Surprisingly, the inventors have discovered that by applying certain sequences of grinding carried out with particular types of grinding, it is possible to obtain not only a significant improvement in the gloss, but also in the transparency, of the 'shine and / or stability of the nail varnish compositions thus treated and of the resulting nail varnishes. It is moreover notable that these improvements were obtained without adding additional compounds. Indeed, the addition of additional compounds is always likely to cause unwanted effects on other properties of nail polish formulations.

[0009] Each grinding step generally comprises from 1 to 50, preferably from 2 to 25, particularly preferably from 3 to 10 successive passages in the corresponding grinder.

[0010] Within the meaning of the invention, a "passage" means treatment of the composition from the inlet to the outlet of the corresponding mill. Therefore, a sequence of steps which would include two consecutive steps in the same type of mill, for example the sequence (A) + (A) + (C), is considered within the scope of the present invention as a two-step sequence. grinding stages, namely a single stage (A) [with a number corresponding to the sum of the passages in the type grinder (A)] and a stage (C). On the other hand, a sequence (A) + (C) + (A) is a sequence with three grinding steps.

[0011] The mass flow rate of a passage is generally between 10 and 4000 kg / h, preferably between 20 and 2500 kg / h, particularly preferably between 25 and 2000 kg / h.

[0012] The method according to the invention comprises or can include the use of different crushers. The crushers are as follows:

[0013] (A) A horizontal linear ball mill whose operation is as follows. A pump circulates the product from the tank to the grinder and then from the grinder to the tank. Once in the mill, the balls move thanks to the vertical axes present inside the chamber. The type of axis may be different depending on the supplier. The grinding chamber is generally under a cooling water system in order to be able to control the temperature. The crusher has flat and wide discs. The variable parameters are generally the speed of the axes (Tip speed 8-16 m / s), the flow (0-1000 kg / h), the size of the balls (2 mm to 0.3 mm). Examples of providers and models are VMA, WAB (KD 45, KD 120, KD 280 and KD 600, ECM AP 20, ECM APO5, ECM AP60), Aleha, Netzsch (NEOS 20, MACRO 20, DISCUS 300).

[0014] (B) A vertical linear ball mill. The operation of the mill is similar to the horizontal linear ball mill and has the same parameters. In contrast, the crusher has disks with gears. A supplier and models are for example Bühler (Micromedia, SuperFlow, Visconomic +, Cenomic).

[0015] (C) A high pressure mill. The liquid is placed under a defined pressure and this pressure allows better dispersion / homogenization of the product. You can adjust the pressure (0 - 1000 bar) as well as the product flow rate for production machines. Examples of suppliers and models are Netzsch (Omega), Ax flow (APV 1000, Rannie 5525.95X, Rannie 125T 40X), Microfluidics (M-7250-20, M7250-30, M710).

[0016] (D) A basket ball mill. In this one, the dye is put in a tank then a basket plunges into the tank. In this basket, there are balls which are stirred thanks to the mixer. A sieve keeps the balls in motion and the liquid circulates inside the tank. The variable parameters are the size of the balls (2 mm to 0.3 mm) and the speed of the mixer. Examples of suppliers and models are IEC +, VMA (TML 1, TML 50), Sozer, Vibromac (SMS LABO, SMC Pilot, SMC 20), Niemman.

[0017] (E) A three-cylinder mill. The three-cylinder crusher consists of three cylinders that rotate to crush pigments, clays, etc. The middle cylinder (2) rotates in the opposite direction to the cylinder (1) and (3). The material enters the rollers (1) and (2) then circulates between the rollers (2) and (3) and flows over the scraper blade. The spacing of the cylinders and the speed of rotation of the cylinders can be varied. Examples of suppliers and models are Keith machinery (anthony six series MKII), EXAKT (120E-250, 120S-450, 120EH-450), Bühler (Fully hydraulic three-roll mills SDX, SDW, SDY, SDV (E) , Trinomic ™).

[0018] (F) An ultrasonic mill. An ultrasound probe is immersed in the coloring solution to be ground and a wave amplitude is given in order to shatter the aggregates of pigments, clays, etc. The variable parameter is the amplitude of the wave. An example of a vendor and a model is Hielscher (UIP series).

[0019] For the purposes of the invention, the term "transparent nail varnish base" means a "conventional" nail varnish comprising at least one fimogenic agent, at least one organic solvent, at least one plasticizer, optionally at least one. resin, optionally various additives such as one or more UV absorbers, surface modifiers as well as so-called “treating” additives for the nail, but no pigments. These compositions for nail varnish can be used as a base coat for varnish (also called base-coat according to English terminology) or as a finishing composition (also called top-coat according to English terminology).

[0020] The film-forming agent can be selected from the group consisting of cellulose, a cellulose derivative, a vinyl resin, an acrylic resin, and any combination thereof. Cellulose derivatives are, for example, nitrocellulose, acetate butyrate cellulose, ethylcellulose and hydroxypropylcellulose. Preferably, nitrocellulose will be chosen as film-forming agent.

A film-forming agent alone or a combination of fimogenic agents can be used in the composition for nail varnish in the proportions ranging from 6% to 20% by dry weight and preferably from 10% to 16% by dry weight relative to the total weight of the composition.

The organic solvent can be selected from the group consisting of toluene, xylene, methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, acetate of propyl, a ketone, an ester, an alcohol, such as denatured ethanol (with methyl ethyl ketone or diethyl ether), isopropanol, butanol, diacetone alcohol, linear or cyclic hydrocarbons, such as for example hexane, cyclohexane, heptane and any combination thereof. In addition, preferably, the amount of organic solvent present in the composition for nail varnish is between 60% and 80% by weight relative to the total weight of the composition.

[0023] The plasticizers which can be used in the composition for nail varnish are acety! tributyl citrate, acetyl triethyl citrate, tributyl citrate, triethylcitrate, dibutyl phthalate, triphenylphosphate, triacetin, trimethyl pentanyl diisobutyrate, triethyihexanoine, sucrose benzoate, dibutyl adiputyl phthalate, diethylisobutyl phthalate, diethylisobutyl phthalate diisopropyl adipate, dipropylene glycol dibenzoate, N-ethyl toluene sulfonamide, its ortho and para isomers, N- (2-hydroxypropyl) benzenesulfonamide and N- (n-butyl) benzenesulfonamide, etc. The plasticizers generally represent from 1 to 12% by dry weight, preferably 5 to 10% by dry weight, in particular from 6 to 8% by dry weight relative to the total weight of the composition.

The resins which can be used in the composition for nail varnish are as follows:

e tosylamide / formaldehyde resins or toluenesulfonamide / formaldehyde resins, e tosylamide / epoxy resins or toluenesulfonamide / epoxy resins, e adipic acid / neopentyl glycol / trimellitic anhydride copolymers, e phthalic anhydride / glycerin / glycidyl decanoate copolymers, e copolymers of phthalic anhydride / glycerin / glycidyl decanoate phthalic anhydride / trimellitic anhydride / glycols, e glycerin / phthalic acid copolymers, e styrene / acrylate / acrylonitrile copolymers, e acrylate polymers and copolymers, e acrylate and styrene copolymers, e sucrose acetate isobutyrate, polyvinylbutyral resin .

[0025] The resins can be used in the formula, alone or in the form of mixtures in amounts ranging from 3 to 20% by dry weight, preferably from 5 to 15% by dry weight, in particular from 7 to 12% by dry weight relative to the total weight of the composition.

Among the UV absorbents that can be used in the composition for nail varnish, we can mention: benzophenone-1 (CAS 131-56-6), benzophenone-3 (CAS 131-57-7), benzyl salicylate (CAS 118-58-1), etocrylene (CAS 5232-99-5), drometrizole (CAS 2440-22-4), butyl methoxydibenzoylmethane (CAS 70356-09-1), etc. The amount of these UV absorbents can range from 0 to 1.5% by dry weight relative to the total weight of the composition.

[0027] Among the additives which can be used in the composition for nail varnish, there will also be mentioned surface modifiers such as cyclomethicones or cyclopentasiloxane, dimethicones and trimethylsiloxysilicate, butyl acrylate / hydroxypropyldimethicone acrylate = copolymer, amodimethicone, acrylates / dimethicone copolymer, etc. These surface additives are generally used in small amounts in the formulation ranging from 0.1 to 5% by dry weight relative to the total weight of the composition.

Among the “treating” additives, we can cite: e formaldehyde used as a nail hardener, e vitamin E acetate (tocopheryl acetate), e vitamin A palmitate (retinyl palmitate), e organic or inorganic derivatives of calcium such as calcium chloride, calcium pantothenate, e dimethyloxobenzodioxasilane, e myrrh, e sulfur-containing amino acids such as cysteine, its salts and their derivatives, cystine, glutathione. Sulfur-containing amino acids are indeed capable of creating cross-linking bridges between keratin and the free SH groups of these sulfur-containing derivatives, e hydrolyzed keratin of plant origin, e alpha-hydroxy acids such as citric acid, acid ascorbic acid, biotin, and urea and dimethylurea.

The treating additives can represent from 0.01% to 5% by dry weight, preferably from 0.05% to 2% by dry weight relative to the total weight of the composition.

[0030] Within the meaning of the invention, the "thixotropic base for nail varnish" comprises, in addition to the transparent base for nail varnish defined above, at least one thixotroping agent chosen from silicas and / or clays .

Suitable thixotroping agents are for example fumed silica which is either in the form of hydrophilic fumed silica, or hydrophobic fumed silica, and / or modified clays, such as for example stearalkonium hectorite or stearalkonium bentonite or even a mixture of both.

Pyrogenic silicas can be obtained by high temperature hydrolysis of a volatile silicon compound in an oxyhydrogen flame, producing a finely divided silica. This process makes it possible in particular to obtain hydrophilic silicas which have a large number of silanol groups at their surface. Such silicas are known under the trade name HDK

(INCI: silica) as for example, HDK N20, HDK N20D, HDK N20P, HDK N20ST, HDK S13, HDK T30, HDK T30P, HDK T40, HDK V15, or under the trade name Aerosil (INCI: silica) as for example , Aerosil 200, Aerosil 300, etc.

It is possible to modify the surface of said silica, by chemical reaction generating a decrease in the number of silanol groups. It is in particular possible to substitute silano groups! by hydrophobic groups: a hydrophobic silica is then obtained. Such silicas are known under the trade name HDK, HDK H18 (INCI: Silica Dimethyl Silylate), H13L (silica Dimethylsiloxy), or under the trade name Aerosil, Aerosil R202 (INCI: silica dimethicone silylate), Aerosil R972 (INCI : silica dimethyl silylate), Aerosil R812 (INCI: silica silylate),…

The fumed silica preferably has a specific surface (BET) of between 20 and 500 m ° / g. The composition for nail varnish, respectively the base, can comprise pyrogenic silica in an amount ranging from 0.02% to 3% by weight, preferably from 0.2% to 1% by weight, relative to the total weight. of the composition.

The clays can be modified or not, they are for example clays modified with quaternary ammonium cations, such as for example benzalkoniums, in this case for example stearalkonium hectorite, stearalkonium bentonite ,. .., or by alkylammonium ions, such as cetrimonium hectorite, cetrimonium bentonite,…

The clays, modified or not, are preferably present in an amount of 0.1% to 4% by dry weight relative to the total weight of the composition for nail varnish, respectively of the base.

[0037] Within the meaning of the invention, a composition for pigmented nail varnish, respectively a "pigmented base for nail varnish", comprises, in addition to the thixotropic base for nail varnish defined above, one or more pigments . In particular, the pigment (s) used can be selected from the group comprising titanium dioxide (CI 77891), black iron oxide (CI 77499), red iron oxide (CI 77491), DC Red 6 Ba Lake (CI 15850), DC Red 7 Ca Lake (CI 15850: 1), DC Red 34 Ca Lake (CI 15880), FDC Yellow 5

Al Lake (CI 19140), FDC Blue 1 Al Lake (Ci 42090), ultramarine blue (CI 77007), DC Violet 2 (CI 60725), DC Black 2 (CI 77266), etc. The composition for pigmented nail varnishes comprises an amount of coloring agent of from 0.1% to 20% by dry weight and preferably from 0.5% to 12% by dry weight relative to the total weight of the composition.

The invention therefore relates to a particular treatment of a composition for nail varnish comprising solid components which are difficult to dissolve, or even insoluble or particulate, chosen from a transparent nail varnish base, a thixotropic nail varnish base and / or a pigmented base of nail polish in which a grinding sequence is carried out with a combination of different types of mills, namely horizontal or vertical linear ball mills, a high pressure mill, a basket ball mill, a grinder three-cylinder or ultrasonic crusher. The inventors have found that in addition to improved gloss, transparency and luster of the base, pigment pastes and tints are exceptional. The ingredients used are identical but this sequence allows a significant improvement on the finished product. In fact, the grinding sequences according to the invention make it possible to gain 5 a points of brilliance, brightness of the colors, transparency and a gain in stability over time, compared with the conventional treatment with a single type of grinder.

In another aspect, the invention also relates to the use of a combination of grinding steps chosen from (A) grinding in a horizontal linear ball mill, (B) grinding in a ball mill vertical linear, (C) grinding in a high pressure mill, (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step chosen from (A) or (B) and at least one step (C) for increasing the gloss, transparency, brilliance and / or the stability time of a composition for nail varnish comprising non-soluble or particulate solid components, chosen from a transparent nail varnish base, a thixotropic nail varnish base and / or a pigmented nail varnish base. Description of preferred executions

[0040] Material and Methods:

[0041]!) Material:

The following compositions of transparent base for nail varnish, thixotropic base for nail varnish and pigmented base for nail varnish (Table 1) were used.

[0043] Table 1: us °. Base Base Base Ingredients (% by weight) Function | transparent | thixotropic | pigmented 2 a Solvent 2 Solvent Iso-propyl alcohol (from nitrocellulose) Solvent 3.9 3.6 8.4 Epoxy tosylamide Dacryial gopolymers Resne | 0235 | bone | oi | styrene Phthalic Anhydride / Trimellitic Resins Anhydride / Glycols copolymer (additional 9.65 8.45 dry weight) Nitrocellulose (dry weight) Acetyl Tri-butyl Citrate Plasticizer. Agent i. Agent Pigments eliou dyes eUou pearlescent | __ | TS) Tota [| 10 | 100 | 100 |

The following grinding sequences, as well as the following grinders were used:

Regarding the transparent nail varnish base, it has been subjected to at least 1 pass through the horizontal linear ball mill. The following mass flow and velocity parameters were applied: 150 kg / h and 13 m / s. The transparent nail polish base was then subjected to 2 passes through the high pressure mill with a pressure of 1000 bar and L / h.

Regarding the thixotropic base of nail varnish, it was subjected to 2 passes in the high pressure mill with a pressure of 850 bar and 18 L / h, then the thixotropic base of nail varnish was subjected to 3 passes through the vertical linear ball mill. The following mass flow and velocity parameters were applied: 400 kg / h and 16 m / s.

Regarding the pigmented base of nail varnish, it was subjected to 9 passes in the horizontal linear ball mill. The following mass flow and velocity parameters were applied: 900 kg / h and 16 m / s. The pigmented nail varnish base was then subjected to 1 pass through the high pressure mill with a pressure of 1000 bar and 20 L / h.

[0048] II) Measurement methods:

The following properties of the three different nail polish bases were measured: the shine of the nail varnish base, the clarity of the nail varnish base which combines the parameters of transparency and radiance of the base of nail polish, as well as the stability time measured via the thixotropic index. In addition, the appearance of the film of the three different nail varnish bases which results from all of the parameters mentioned above was also measured.

To determine the gloss of the film formed, the glossmeter analysis is carried out on dry films applied to standardized contrast cards using an applicator allowing the formation of a wet film with a thickness of 100 pm. The deposited film is dried at 30 ° C. for 12 h. The gloss is measured at an angle of 60 ° to the normal of the film and is performed three times. The final value obtained is the average of these three measurements.

Regarding the measurement of thixotropy, three different measurements are performed corresponding to the different stresses undergone by the varnish during application. A first measurement of viscosity is carried out for the varnish at rest, the spindle of the viscometer rotates at a speed of 6 rpm for one minute. It then goes to 60 rev / min to model the mixture in the bottle (second viscosity measurement), then the application to the nail when the varnish is again at rest. Finally, the speed of rotation returns to 6 rpm to model the behavior of the varnish once it has been spread on a nail (third viscosity measurement) and therefore at rest. The ratio between the third viscosity measured at 60 rpm and the second viscosity measured at 6 rpm gives the thixotropic index.

[0052] Regarding the clarity of the nail polish base, this parameter is evaluated visually on real nails, on a plastic nail so as not to have the impact of the surface roughness of a real nail. The 3 different nail polish bases were also applied on a contrast card and are blind tested, i.e. a panel of users chooses the nail polish base they prefer from among two choices in each category of nail polish bases.

[0053] Regarding the appearance of the film, this parameter is evaluated visually on real nails, on a plastic nail plate so as not to have the impact of the surface roughness of a real nail and on a contrast card. The 3 different nail polish bases were also subjected to the knife scratch test. The appearance of the film is tested using a knife with four parallel blades. The plate where one of the nail polish bases has been placed is scratched vertically and horizontally so as to draw small squares. It is by observing the detachment of the parts of said nail polish base that we qualify the appearance thereof.

[0054] The separate formulations were also evaluated by a panel of users. In particular, the properties of gloss, clarity and appearance of the film. Users applied each composition to their nails to assess their properties.

Tables 2-4 below illustrate the different formulations used by the process according to the invention, the different grinding sequences tested and their effects on the gloss, the clarity, the appearance of the film and the thixotropy of the compositions. of nail polish. The grinding sequences according to the invention were compared with the conventional treatment with a single type of grinder.

[0056] Table 2: Transparent base of Brilliance nail varnish | Clarte | ASPECtAU | Thixotropy film Grinding Compara Grinding (8) Compara) Grinding (©) Camper Grinding D) Compara Sequence 2 Grinding (A) (comparative) ++ + + + ++ Sequence 2 Grinding (d) (comparative) + + + + ++ Sequence (A) + (C) Sequence (C) + (A) Sequence (B) + (©) Sequence (C) + (8) Consecutive sequence (A) + (C) + (A) +++ ++ + +++ ++++ +++ Consecutive sequence (C) + (A) + (C) ++++ ++++ +++ ++++ ++++ Consecutive sequence (A) + ( D) + (C) +++ +++ +++ +++ ++ Consecutive sequence (A) + (D) + (C) + (F) ++ ++ ++ ++ +++ Sequence ( E) + (B) + (©) consecutive sequence (E) + (A) + (C) ++ ++ ++ ++ ++

[0057] Table 3:

PO ET [mm] em [Ere re Wem 1 Je oe fee fe (A) (comparative) ++ ++ ++ +++ +++

CA CE (C) (comparative) + + + +++ +++ SEO es fee fee eee fe + (F) +++ +++ +++ ++++ +++

[0058] Table 4: PU Low sales peppers Nail [men Em ree ee man Jee fe fee Jee eee (comparison) ++ ++ +++ +++ +++++ CA fe ee fee (comparison) + + ++ +++ +++ +++++

[0059] Ill) Results:

It is observed that by applying certain grinding sequences carried out with particular types of grinding, it is possible to obtain not only a significant improvement in the gloss (the process makes it possible to gain 5 to 10 points), but also to the transparency, the brightness and / or the stability of the nail varnish compositions thus treated and of the resulting nail varnishes by comparison with a grinding using only one type of grinder. In fact, it is observed that the sequences comprising at least one step chosen from (A) or (B) and at least one step (C) result in compositions having a gloss, clarity, thixotropy and appearance of the film superior to the other sequences comprising different grinders and much better than sequences using a single grinder.

Claims (14)

Claims 1. Process for improving the gloss, transparency, brilliance and / or stability time of a composition for nail varnish comprising insoluble or particulate solid components, chosen from a transparent base of varnish with nails, a thixotropic nail polish base and / or a pigmented nail polish base, said method comprising subjecting said nail varnish composition to a sequence of two or more grinding steps selected from (A) a grinding in a horizontal linear ball mill, (B) grinding in a vertical linear ball mill, (C) grinding in a high pressure mill, (D) grinding in a basket ball mill, (E) a grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step chosen from (A) or (B) and at least one step (C). 2. Method according to claim 1, wherein a grinding step comprises from 1 to 50, preferably from 2 to 25, particularly preferably from 3 to 10 successive passes through the corresponding grinder. 3. Method according to claim 2, wherein the mass flow rate of one passage is between 10 and 4000 kg / h, preferably between 20 and 2500 kg / h, particularly preferably between 25 and 2000 kg / h. 4. Method according to any one of claims 1 to 3 wherein the composition for nail varnish is a transparent nail varnish base which comprises at least one film-forming agent, at least one organic solvent, at least one plasticizer, optionally at least. less one resin, possibly various additives. 5. The method of claim 4, wherein the film-forming agent (s) are selected from cellulose, a cellulose derivative, a vinyl resin, an acrylic resin or any combination thereof, preferably the film-forming agent is nitrocellulose. 6. The method of claim 4 or 5, wherein the organic solvent (s) is (are) chosen from toluene, xylene, ethyl acetate, butyl acetate, isobutyl acetate, acetate. propyl, methyl acetate, a ketone, an ester, isopropanol, butanol, diacetone alcohol, ethanol denatured with methyl ethyl ketone or diethyl ether, linear or cyclic hydrocarbons, preferably hexane, cyclohexane , heptane, or any combination thereof. 7. Method according to one of claims 4 to 6, wherein the plasticizer or plasticizers are chosen from acetyl tributyl citrate, acetyl triethyl citrate, tributyl citrate, triethyl citrate, dibutyl phthalate, triphenylphosphate, triacetin , trimethyl pentanyl diisobutyrate, triethylhexanoin, sucrose benzoate, dibutyl adipate, diethyl phthalate, diisobutyl adipate, diisopropyl adipate, dipropylene glycol dibenzoate, N-ethyl toluene sulfonamide, its ortho and para isomers (2-hydroxypropyl) benzenesulfonamide and N- (n-butyl) benzenesulfonamide, or combinations thereof. 8. Method according to one of claims 4 to 7, wherein the transparent nail varnish base further comprises one or more additives selected from resins, UV absorbers, surface modifiers and so-called "treating" agents. 9. Method according to any one of claims 1 to 3, in which the composition for nail varnish is a thixotropic base for nail varnish which comprises at least one thixotroping agent chosen from modified or unmodified silicas and / or modified clays. or not. 10. A method according to any one of claims 1 to 3, wherein the composition for nail varnish is a pigmented base for nail varnish which comprises as pigments one or more of the pigments selected from titanium dioxide (CI 77891), black iron oxide (CI 77499), red iron oxide (CI 77491), DC Red 6 Ba Lake (CI 15850), DC Red 7 Ca Lake (C! 15850: 1), DC Red 34 Ca Lake (CI 15880), FDC Yellow 5 Al Lake (CI 19140), FDC Blue 1 Al Lake (CI 42090), ultramarine blue (CI 77007), DC Violet 2 (CI 60725) and DC Black 2 (CI 77266). 11. Using a combination of milling steps selected from (A) milling in a horizontal linear ball mill, (B) milling in a vertical linear ball mill, (C) milling in a high pressure mill. , (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step selected from (A) or ( B) and at least one step (C) for increasing the gloss of a composition for nail varnish comprising solid insoluble or particulate components, chosen from a transparent base of nail varnish, a thixotropic base of nail varnish and / or a pigmented base of nail polish. 12. Using a combination of milling steps selected from (A) milling in a horizontal linear ball mill, (B) milling in a vertical linear ball mill, (C) milling in a high pressure mill. , (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step selected from (A) or ( B) and at least one step (C) for increasing the transparency of a composition for nail varnish comprising solid insoluble or particulate components, chosen from a transparent nail varnish base, a thixotropic nail varnish base and / or a pigmented base of nail polish. 13. Using a combination of milling steps selected from (A) milling in a horizontal linear ball mill, (B) milling in a vertical linear ball mill, (C) milling in a high pressure mill. , (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step selected from (A) or ( B) and at least one step (C) for increasing the shine of a composition for nail varnish comprising solid insoluble or particulate components, chosen from a transparent nail varnish base, a thixotropic nail varnish base and / or a pigmented nail polish base. 14. Using a combination of milling steps selected from (A) milling in a horizontal linear ball mill, (B) milling in a vertical linear ball mill, (C) milling in a high pressure mill. , (D) grinding in a basket ball mill, (E) grinding in a three-cylinder mill, (F) grinding in an ultrasonic mill, according to a sequence comprising at least one step selected from (A) or ( B) and at least one step (C) for increasing the stability time of a composition for nail varnish comprising solid insoluble or particulate components, chosen from a transparent nail varnish base, a thixotropic nail varnish base and / or a pigmented nail varnish base.