JP2003073233A - Cosmetic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cosmetic having the excellent touch and slipperiness during coating on the skin. SOLUTION: This cosmetic comprises fine particles and other cosmetic raw materials. The fine particles are formed of a biodegradable polyester resin containing >=50 mol% of lactic acid units in the resin ingredient and having 0.1-25 mol% of D-isomer content in the lactic acid units. In the fine particles, >=70% of the total number thereof satisfies the ratio of the major axis to the minor axis of (major axis)/(minor axis) <=1.5 and the density is 1.0-10.0 g/cm<3> . The average particle diameter is 0.01-1,000 μm and the 10% distortion strength during compression is >=5 MPa.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cosmetics used for skin, hair and the like, and more particularly to cosmetics using fine particles made of a biodegradable polyester resin.

[0002]

2. Description of the Related Art As a cosmetic raw material for improving the skin feel (moistness, smoothness, etc.) of cosmetics and the slipperiness during application, or for improving the slipperiness and feel during the use of hair cosmetics. It is well known to incorporate polymer microparticles, such as, cross-linked silicone particles, nylon particles, vinyl or acrylic radical polymer particles, into the cosmetics. As this type of cosmetics, cosmetics containing crosslinked silicone particles having a three-dimensional network structure (Japanese Patent Laid-Open No. 1-165509 and Japanese Laid-Open Patent Application No. 1-1919).
No. 0757), cosmetics containing a silicone oil emulsion composed of a silicone cross-linked product (see JP-A-3-79669), and cosmetics containing substantially spherical polyamide particles of a specific size (JP-A No. 07-79669). 7-
300410) and cosmetics containing polymer fine particles such as specific polymethylmethacrylate and polystyrene (Japanese Patent Publication No. 10-502389).

However, these polymer fine particles are mainly produced from petroleum raw materials, and although their safety to the skin has been confirmed, they meet the needs of consumers who want to use safer ones. Has not been done. Further, these polymer fine particles are not easily decomposed in the natural world, and if they are released into the natural world after being used as cosmetics, they will remain as dust or deposits for a long time, or the load on the furnace during incineration treatment will be great. The load on the environment is large, such as being large.

For this reason, biodegradable resins, which have the characteristic that they have a low impact on the environment, are attracting attention. Although biodegradable resins are limited in terms of physical properties, so far, sheets,
It has been put to practical use after being processed into films, fibers, spunbonds, etc. The processing of the biodegradable resin into a particle shape has hitherto been performed by the foam of the biodegradable resin disclosed in JP-A-5-170965 and the like, and the biodegradable resin disclosed in JP-A-9-78494. The water dispersions, emulsions, etc. have been studied and proposed as substitutes for resins produced from petroleum raw materials. In particular, as a capsule for so-called drug delivery, which releases a drug in vivo or the like, it has been studied and put to practical use for a long time, as disclosed in Japanese Patent Publication No. 1-5005.

Several proposals have been made so far for aqueous dispersions of biodegradable resins. JP-A-9-779
No. 10, etc., a starch derivative, WO9704036, a polyhydroxyalkanoate, “Colloidal Polymer Journal”, volume 273, page 501 (1995), polycaprolactone, and JP-A No. 11-92712, a fat. Aliphatic polyesters composed of group dicarboxylic acids and glycols are disclosed, respectively.

However, these biodegradable resins are
Since both have a low melting point or decomposition temperature, the temperature range is limited when they are used as cosmetics, and problems easily occur during storage at high temperatures such as in summer. Further, when the fine particles are taken out from the emulsion form by drying, only spherical particles having poor mechanical strength can be obtained. For this reason, when added to cosmetics, the fine particles are easily deformed from a spherical shape, and therefore their rolling performance is easily deteriorated, which makes them unsuitable for use as a feel-improving material or a slipping-improving material when applied to skin or the like. Is.

Among the biodegradable resins, however, polylactic acid has a relatively high melting point or softening point of about 100 to 170 ° C. and is also excellent in water resistance, and is therefore suitable as fine particles as a raw material for cosmetics. .

Regarding polylactic acid-based aqueous dispersions, researches on microencapsulation for the purpose of sustained drug release have been actively conducted. For example, JP-A-63-122620, JP-A-5-58882, and JP-A-6-728.
No. 63 and Japanese Patent Application Laid-Open No. 9-110678 disclose a microencapsulation technique using a lactic acid-based polymer. In these, the lactic acid-based polymer is dissolved in an organic solvent, the drug is dissolved or dispersed therein, and then the solution is dropped or mixed in an aqueous solution containing a surfactant, and stirred to perform phase inversion emulsification A method of forming an oil (O / W) type emulsion has been adopted. However, since a large amount of organic solvent is used, it is difficult to completely remove the solvent, and since the steps of solvent distillation and recovery are not a completely closed system, there are problems that the influence on the surrounding environment cannot be ignored.
Also, with this method, it is difficult to obtain relatively large particles exceeding 1 μm that are useful for cosmetics.

A method for producing fine particles of polylactic acid resin in the form of an emulsion (aqueous solution) has also been proposed (Japanese Patent Application No. 2000-370106), but also in this case, the fine particles are taken out from the emulsion form by drying. Although it can be made spherical, it has only poor mechanical strength. Therefore, it is not suitable for use as a feel-improving material or a slip-improving material when applied to cosmetics.
Even with the method of forming fine particles after being dissolved in an organic solvent, the mechanical strength is slightly improved.

On the other hand, expanded particles can be obtained by a method in which the biodegradable resin is crushed, then impregnated with an organic solvent or the like, and then expanded. However, such foamed particles can be obtained only with a low density, and there is a problem in terms of strength and specific gravity as a material for cosmetics. There is also a problem in using an organic solvent here.

Japanese Unexamined Patent Publication No. 2000-220994 discloses that
Disclosed is a biodegradable ball which is obtained by processing a biodegradable material made of a thermoplastic resin containing polylactic acid as a main component into a spherical shape. However, with this technique, it is possible to obtain particles having a large outer diameter of about 30 mm,
It is not possible to produce fine particles having a diameter of 1 mm or less, which is suitable as a material for cosmetics.

Furthermore, in any of the above methods, it is very difficult to incorporate an inorganic or organic or inorganic / organic composite material into the resin in order to improve the properties of cosmetics, and biodegradable polyesters containing these are included. No resin composite fine particles have been obtained.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and an object thereof is to provide a cosmetic product which is excellent in touch and slipperiness during application.

[0014]

The cosmetic of the present invention contains fine particles and other cosmetic raw materials, and the fine particles contain 50 mol% or more of lactic acid units in a resin component and D-form in the lactic acid units. It is formed of a biodegradable polyester resin having a content of 0.1 to 25 mol%, and 70% or more of the total number of the fine particles has a ratio of major axis to minor axis of (major axis) / (minor axis) ≦ 1. 0.5, and the density is 1.0-10.0 g / cm ³
The average particle size is 0.01 to 1000 μm, and the 10% deformation strength during compression is 5 MPa or more. Such a cosmetic product has a very high strength of fine particles and is very effective in improving the feel and the slipperiness when applied to the skin and the like. Moreover, the fine particles can be easily and inexpensively produced without using an organic solvent and without using special equipment or complicated operations.

The cosmetic of the present invention contains lactic acid in an amount of 0.1 to 100.
It is preferable to contain 0 ppm. As a result, since lactic acid liberated from polylactic acid is present in the cosmetic, it is easy to keep the skin weakly acidic, and the cosmetic can be made gentle to the skin.

[0016] In the cosmetics of the present invention, the total amount of the fine particles is 100% by volume, and in addition to the biodegradable polyester resin, at least one component selected from inorganic substances and / or organic substances is contained in an amount of 1 to 95% by volume. % Can be contained. According to the present invention, the properties of cosmetics can be improved by containing at least one kind of component selected from an inorganic substance and / or an organic substance as described above.

The method for producing cosmetics of the present invention uses a biodegradable polyester resin containing 90 mol% or more of lactic acid units and 0.1 to 25 mol% of D-form content in lactic acid units. Moisture content of degradable polyester resin is 1
It is dried to a concentration of 000 ppm or less, a melt-kneading method is applied to the dried resin to produce fine particles, and the fine particles are added to the other cosmetic raw material. In this way, the biodegradable polyester resin mainly containing lactic acid is dried so that the water content is 1000 ppm or less, and the melt kneading method is applied to this dried resin to produce fine particles. Since the fine particles have a low content of lactic acid monomer, the content of lactic acid in cosmetics can be set within the above-mentioned preferable range of 0.1 to 1000 ppm.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The biodegradable polyester resin constituting the fine particles used in the cosmetic of the present invention is a lactic acid-based polymer containing a lactic acid unit as a main component, and is an essentially hydrophobic polymer that does not disperse or dissolve in water by itself. The constituent components of the biodegradable polyester resin will be described below.

The biodegradable polyester resin used in the present invention includes homopolymers of lactic acid, or lactic acid and other hydroxycarboxylic acids such as glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid and 4-hydroxy. Examples thereof include copolymers with valeric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid and the like. Alternatively, a copolymer of lactic acid with an aliphatic or aromatic carboxylic acid and glycolic acid can be used. Alternatively, a mixture of polylactic acid and another polyhydroxycarboxylic acid, polycaprolactone, an aliphatic polyester, an aliphatic / aromatic polyester, or the like can be used.

The lactic acid unit in the biodegradable polyester resin needs to be 50 mol% or more, preferably 70 mol% or more, more preferably 90 mol% or more. When the lactic acid unit is less than 50 mol%, the heat resistance of the resin coating obtained from the water dispersion is low and it is not practical as a cosmetic.

By releasing a small amount of lactic acid from polylactic acid,
By keeping the cosmetics weakly acidic and using this cosmetics,
It has the effect of keeping the skin slightly acidic. The liberated lactic acid is
It is effective that the aqueous solution at 30 ° C. has a concentration of 0.1 to 1000 ppm. For that purpose, it is required to be a biodegradable polyester containing 50 mol% or more of lactic acid units as described above. If the lactic acid unit in the biodegradable polyester resin is less than 50 mol%, the amount of lactic acid will be less than 0.1 ppm, and the acidity of the cosmetic will be insufficient. The effect of keeping on is reduced. On the other hand, when the residual amount of the monomer in the polylactic acid is too large, the amount of lactic acid in the cosmetic product is more than 1000 ppm, which is a level that adversely affects the skin. For this reason, it is necessary to reduce the amount of monomers present in polylactic acid as much as possible to reduce the amount of lactic acid in cosmetics to 1000 ppm or less as described above.

The content of D-lactic acid in the lactic acid unit is 0.1.
It is necessary to be 25 mol%, preferably 0.
It is 5 to 20 mol%, more preferably 1 to 15 mol%. It is substantially difficult to produce polylactic acid fine particles having a D-lactic acid content of less than 0.1 mol%. On the contrary, D
-When the content of lactic acid exceeds 25 mol%, the glass transition temperature and the melting point are lowered, and the heat resistance required for cosmetics of the obtained fine particles is lowered, and the cost is increased.

In the present invention, the 10% deformation strength of the biodegradable polyester resin fine particles when compressed (the measuring method will be described later) needs to be 5 MPa or more, and particularly preferably 10 MPa or more. 10% deformation strength is 5 MPa
When the amount is less than the above, the original spherical body is likely to be transformed into a non-spherical body when blended in cosmetics, and thus the effect of improving the feel and the slipperiness during application is reduced.

The biodegradable polyester resin used in the cosmetics of the present invention has a number average molecular weight of 2,000 to 1,000,000 as measured by GPC (gel permeation chromatography, converted to polystyrene).
It is preferably within the range. Below 2,000,
Sufficient strength cannot be imparted, and therefore polylactic acid is decomposed to generate lactic acid, so that the lactic acid concentration in the cosmetic product becomes too high. Further, it is difficult to obtain a high molecular weight polymer having a molecular weight exceeding 1,000,000.

In order to improve the properties of cosmetics, it is preferable to use composite fine particles in which a biodegradable polyester resin mainly composed of polylactic acid contains an inorganic or organic or inorganic / organic composite substance.

The inorganic / organic compound capable of forming such composite fine particles is not particularly limited as long as it can stably exist in the biodegradable polyester resin, and various inorganic compounds, various organic compounds, Inorganic / organic composite materials can be used.

Examples of inorganic compounds suitable for improving the properties of cosmetics include various metals, various metal compounds, and various ceramics. Specifically, aluminum, silicon, titanium, iron, nickel, copper, zinc, selenium, zirconium, molybdenum, ruthenium,
Examples thereof include palladium, silver, indium, tin, antimony, platinum, gold, bismuth and the like. Further, oxides, nitrides, halides, carbonic acid compounds, hydroxide compounds, phosphoric acid compounds, sulfur compounds and the like of these elements and elements including the groups 1 to 3 of the periodic table can be mentioned. Further, composite compounds of these compounds, alloys, natural / synthetic minerals and the like can be mentioned.

Examples of organic compounds include various synthetic resin compositions, oligomers, natural compounds and carbon compounds. Specifically, hydrocarbon resins such as polyethylene and polypropylene, acrylic acid resins, vinyl acetate resins, diene compounds, polyethers, phenol resins, amino resins, aromatic hydrocarbon resins, polyester resins, polyamide resins , Silicone resin, furan resin,
Examples include polyurethane resins, epoxy resins, cellulosic compounds, proteins, amino acids, and their carbides. Of these, it is desirable to use naturally occurring compounds or compounds that exhibit biodegradability. One or more of these compounds may be used, and an inorganic / organic compound may be mixed and used.

Further, when classifying the inorganic / organic compounds used for preparing the composite fine particles from the viewpoint of their useful function as cosmetics, substances that absorb or scatter ultraviolet rays,
There are pigments, dyes, infrared absorbers, electromagnetic wave and radiation absorbers, and the like. Generally, it is classified into a color pigment, an extender pigment, a mixture of color pigments, an extender pigment coated with a color pigment, and the like.

Examples of color pigments are titanium oxide (titanium white, titanium black), zinc oxide, iron oxide (red iron oxide, yellow iron oxide, black iron oxide, ultrafine iron oxide), alumina, aluminum hydroxide, zirconium oxide, Examples thereof include titanium nitride, zirconium nitride, selenium oxide, silicon carbide, silicon nitride, boron carbide, boron nitride and strontium zinc aluminate zinc sulfide. As extender pigments, talc, kaolin, mica, sericite, ocher, amber, titanium dioxide, zinc oxide, montmorillonite,
Examples thereof include mica, clay and bentonite.
Examples of the mixture of color pigments include simple mixtures and color pigments coated with color pigments.Specifically, titanium dioxide-coated mica, red iron oxide, black iron oxide, ultramarine blue, dark blue, carbon black, titanium black, etc. Examples include mica titanium coated with at least one kind. Examples of extender pigments coated with color pigments include extender pigments coated with at least one of titanium dioxide-coated mica, red iron oxide, black iron oxide, ultramarine blue, dark blue, carbon blank, and titanium black.

The various compounds as described above (hereinafter referred to as "composite compound") for use in the composite fine particles may be liquids or gases, but solid substances are easy to handle in operation. When using a solid complex compound, the initial particle size is not particularly limited. However, even if the initial particle size is large, it is preferable to use one that is atomized during the production of the composite particles. The content of the compounding compound is 1 to the whole biodegradable polyester resin composite particles to be produced.
It should be contained in an amount of 95% by volume, and it is preferable that the complexing compound is covered with a biodegradable polyester so that the complexing compound does not come into direct contact with the skin.
When the content ratio of the compounding compound is less than 1% by volume of the whole biodegradable polyester resin composite fine particles, the functionalization due to the compounding is not sufficient, and when it exceeds 95% by volume, it is covered with the biodegradable polyester. Becomes difficult.

The biodegradable polyester resin fine particles (including composite fine particles) used in the cosmetics of the present invention are produced by the following method. That is, first, from a biodegradable polyester resin mainly composed of polylactic acid, or a biodegradable polyester resin mainly composed of polylactic acid and at least one compound compound selected from an inorganic substance and / or an organic substance. The resulting biodegradable polyester resin composition is dried to a water content of 1000 ppm or less. When the water content is more than 1000 ppm, the molecular weight of the biodegradable polyester is lowered and a large amount of lactic acid monomer remains in the produced fine particles, which is not preferable.

Next, the above-mentioned biodegradable polyester resin or biodegradable polyester resin composition (hereinafter, for simplicity, both are collectively referred to as "biodegradable polyester resin composition" or simply "composition"). Is)
The composition is dispersed in fine particles by heating and melting the biodegradable polyester resin composition at a temperature equal to or higher than the melting point of the biodegradable polyester resin composition together with an incompatible dispersion medium. Next, the obtained fine particles of the biodegradable polyester resin composition are cooled to a temperature equal to or lower than the melting point thereof, and a dispersion medium as microspheres having an average particle diameter of about 0.01 μm or more and 1,000 μm or less. It is solidified together with this dispersion medium. Thereby, biodegradable polyester resin fine particles are manufactured. The amount of the dispersion medium used at this time is preferably 1 to 5 times the volume ratio of the biodegradable polyester resin composition.

The heating temperature at the time of mixing may be higher than the melting point of the substance having the highest melting point among the substances constituting the biodegradable polyester resin composition, and preferably 10 higher than the melting point.
~ 200 ° C higher temperature, more preferably 20-100 ° C
Use high temperature. If the heating temperature is too low, the biodegradable polyester resin composition will be insufficiently melted and difficult to be dispersed in the fine particles. On the other hand, if the heating temperature is too high, it is not preferable because the biodegradable polyester resin composition is thermally decomposed and the molecular weight is lowered, and also from the viewpoint that lactic acid as a monomer remains in the resin.

After forming fine particles by cooling and solidification, the mixture of the fine particle biodegradable polyester resin composition and the dispersion medium is a poor solvent (precipitant) and dispersed in the biodegradable polyester resin composition. A solvent that is a good solvent for the medium (hereinafter referred to as "suspension solution-producing solvent") is added and mixed. As a result, the dispersion medium is dissolved to form a suspension of the biodegradable polyester resin composition, and the target fine particles are separated and taken out from the suspension.

As such a dispersion medium, as a hydrophilic substance, polyalkylene oxide (polyethylene glycol, etc.), homopolymer or copolymer of polyalkenecarboxylic acid, or salts thereof (polyacrylic acid, polymethacrylic acid, Examples thereof include at least one of a homopolymer or a copolymer (polyacrylamide, polymethacrylamide) of polyalkene amide) and a polyalkene amide. Examples of the hydrophobic substance include propyl cellulose and polystyrene.

When the biodegradable polyester resin fine particles or composite fine particles used in the cosmetics of the present invention are produced, the biodegradable polyester resin or resin composition is mixed with a dispersion medium and dispersed as fine particles in the dispersion medium. The method and device for performing the process are not particularly limited. For example, rolls, Banbury mixers, kneaders,
It can be dispersed by a single-screw extruder, a twin-screw extruder, or the like. Among them, it is preferable to use a single-screw or twin-screw extruder in terms of continuous productivity and enhancing the strength of fine particles when compressed, and the resin or resin composition and the dispersion medium are melt-kneaded under high shear conditions. A twin-screw extruder that can be used is particularly preferable. The type and size of the twin-screw extruder are not particularly limited, but those having a cylinder length / diameter ratio (L / D) of 20 or more can be preferably used. Such a granulation method is considered to belong to wet agitation granulation. Shearing force by stirring, which is a force for splitting fine particles, and viscoelasticity and interfacial tension of a composition, which is a force for holding fine particles, are considered. It is believed that the particle size is determined by the balance of

When the biodegradable polyester resin fine particles or composite fine particles are produced by the above-mentioned preferred method, the high shearing force applied at that time causes the biodegradable resin molecules to be dispersed in the dispersion medium to a very high degree. Moreover, because of the high shearing force, the fine particles obtained here are presumed to be particularly excellent in compressive strength as compared with the fine particles obtained by other production methods.

As described above, after the resin composition / dispersion medium mixture is cooled to below the melting point and solidified, a suspension-forming solvent that is a poor solvent for the composition and a good solvent for the dispersion medium, and this mixture. In the case of obtaining the cosmetic of the present invention, this mixture may be used as it is as a suspension of fine particles. Alternatively, after the mixture is cooled and solidified, it is crushed with a crusher or the like, pelletized with a pelletizer, extruded, molded into a sheet with a roll or the like, and then mixed with a suspension-forming solvent, You may proceed to the process of preparing a suspension.

Water or an aqueous organic solvent can be used as the suspension-forming solvent for the hydrophilic dispersion medium. For example, when the dispersion medium is polyalkylene oxide or polyalkylene carboxylic acid, water can be used as the suspension-forming solvent as described above.

A hydrophobic organic solvent can be used as the suspension-forming solvent for the hydrophobic dispersion medium.
For example, when propyl cellulose is used as the dispersion medium, toluene, methyl ethyl ketone (MEK) or the like, which is a good solvent thereof, can be used. However, considering the influence on the environment, it is desirable to use the hydrophilic dispersion medium and water as described above.

The desired resin fine particles can be separated from the suspension of the resin / dispersion medium mixture by centrifugation, filtration, or a combination of these methods. The separated fine particles are dried before use, if necessary.

In order to improve the characteristics of cosmetics, the fine particles obtained as described above may be further surface-treated. As a method of surface treatment, a method of coating a metal oxide (oxide of iron, zinc, aluminum, zirconium, cerium, cobalt, etc.) using a wet pulverizer can be adopted (JP-A-8-59433). Issue).

The fine particles or composite fine particles used in the cosmetics of the present invention need to be formed in a spherical shape that is easy to roll in order to improve the feel of the cosmetics and the slipperiness when applied to the skin. is there. As a condition for this spherical shape, it is necessary that 70% or more of the whole fine particles have a ratio of the major axis to the minor axis of 1.5 or less. If this ratio is larger than 1.5, the fine particles become slender and hard to roll, and the strength thereof becomes low, and the particles become more likely to become non-spherical. For this reason,
When the ratio is 1.5% or less and less than 70% of the whole, the rolling properties and strength of the entire fine particles are insufficient.

The density of the fine particles is 1.0 to 10 g / cm ^3.
It is necessary to be. When it is less than 1.0 g / cm ³ , it means that there are voids in the fine particles, and the strength thereof decreases. If it is larger than 10 g / cm ³ ,
Since the difference in density with other materials that are raw materials for cosmetics becomes large, problems occur during kneading.

The average particle size of the fine particles is 0.01 to 1,000.
It must be 0 μm. Above all, the average particle size is 1
Particles of -100 μm are preferably used in many cosmetic applications. It is difficult to produce fine particles having an average particle diameter of less than 0.01 μm, and the yield is low. In addition, static electricity and moisture absorption easily occur, making it difficult to handle as powder. On the contrary, when it exceeds 1,000 μm,
Yield is poor and cost is high.

Next, the cosmetics of the present invention using the above fine particles will be described in detail. The cosmetic of the present invention is characterized by comprising biodegradable polyester resin fine particles or biodegradable polyester resin composite fine particles and another cosmetic raw material. The types of cosmetics of the present invention include cleaning cosmetics such as soaps, body shampoos and wash creams; basic cosmetics such as lotions, creams, emulsions and packs; base make-up cosmetics such as powders and foundations; lipsticks and blushers. , Eye shadow, eyeliner, mascara and other eyebrow cosmetics; manicure and other makeup cosmetics; shampoo, hair rinse, hair conditioner, hair treatment, set lotion, styling lotion, hair spray, foam styling agent, gel styling agent, Hair cosmetics such as hair liquid, hair tonic, hair cream, hair restorer, hair nourishing agent, hair dye, hair styling agent, perfume, eau de cologne and other aromatic cosmetics, toothpaste, bath agent, depilatory, shaving lotion Specialization of antiperspirant / deodorant, sunscreen, etc. Goods are exemplified. In particular,
Basic cosmetics, skin cosmetics such as makeup cosmetics, or hair cosmetics are preferable. Further, examples of the state of this cosmetic product include an aqueous liquid, an oily liquid, an emulsion, a cream, a foam, a semisolid, a solid, and a powder. It is also possible to use this cosmetic product by spraying.

This cosmetic product comprises the above biodegradable polyester resin fine particles or biodegradable polyester resin composite fine particles and other cosmetic raw materials. As the other cosmetic raw materials, avocado oil, almond oil, olive oil, Cocoa butter, sesame oil, wheat germ oil, safflower oil, shea butter, turtle oil, camellia oil, persic oil, castor oil, grape oil, macadamia nut oil, mink oil, egg yolk oil, mokurou, coconut oil, rosehip oil, hardened oil Oils and fats such as; waxes such as orange luffy oil, carnauba wax, candelilla wax, whale wax, jojoba oil, montan wax, beeswax, lanolin; hydrocarbons such as liquid paraffin, petrolatum, paraffin, ceresin, microcrystalline wax, squalane; laurin Acid, myristic acid, palmitic acid, stearic acid, o Higher fatty acids such as in acid, behenic acid, undecylenic acid, oxystearic acid, linoleic acid, lanolinic acid, and synthetic fatty acids; ethyl alcohol, isopropyl alcohol, lauryl alcohol, cetyl alcohol, cetostearyl alcohol, stearyl alcohol, oleyl alcohol, behenyl alcohol, Alcohols such as lanolin alcohol, hydrogenated lanolin alcohol, hexyldecanol, octyldodecanol, isostearyl alcohol; sterols such as cholesterol, dihydrocholesterol, phytosterol;
Ethyl linoleate, isopropyl myristate, isopropyl lanoline fatty acid, hexyl laurate, myristyl myristate, cetyl myristate, octyldodecyl myristate, decyl oleate, octyldodecyl oleate, hexyldecyl dimethyloctanoate, cetyl isooctanoate, palmitate Fatty acid esters such as cetyl, glycerin trimyristate, tri (capryl / capric acid) glycerin, propylene glycol dioleate, glyceryl triisostearate, glyceryl triisooctanoate, cetyl lactate, myristyl lactate, diisostearyl malate; glycerin, propylene Glycol, 1,3-butylene glycol, polyethylene glycol, sodium d, 1-pyrrolidone carboxylate, sodium lactate, Rubitoru, humectant, such as sodium hyaluronate; higher fatty acid soap, higher alcohol sulfuric ester salts, N- acyl glutamates, anionic surfactants such as phosphoric acid ester salts, cationic surfactants,
Amphoteric surfactants such as betaine type, amino acid type, imidazoline type, lecithin, etc., surfactants such as nonionic surfactants such as polyhydric alcohol ester type, ethylene oxide condensation type, etc .;
Colored pigments such as iron oxide, white pigments such as zinc oxide, titanium oxide and zirconium oxide, pigments such as extender pigments such as mica, talc and sericite; dimethylpolysiloxane, methylphenylpolysiloxane, octamethyltetracyclosiloxane, deca Silicone oils such as methylcyclopentasiloxane, polyether modified silicone oil and amino modified silicone oil; purified water; carrageenan, alginic acid, gum arabic, tragacanth, pectin, starch, xanthan gum, polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate, polyethylene Thickeners such as glycols, silicone / acrylic copolymers, film forming agents such as silicone resins and acrylic polymers, and further ultraviolet absorbers, antibacterial agents, anti-inflammatory agents, antiperspirants, preservatives, fragrances, Preventive agents, pH adjusting agents, propellants and the like.

Next, a method for producing the cosmetics of the present invention will be described. The method for producing cosmetics of the present invention is characterized in that the above biodegradable polyester resin fine particles or biodegradable polyester resin composite fine particles are blended with other cosmetic raw materials. For example, the mixing can be performed by a batch type or continuous type stirring means. Specific devices for this purpose include homomixers, paddle mixers, Henschel mixers, homodispers, colloid mills, propeller stirrers, homogenizers, in-line continuous emulsifiers, ultrasonic emulsifiers, and vacuum kneaders. . The biodegradable polyester resin fine particles or the biodegradable polyester resin composite fine particles may be added to other cosmetic raw materials at any time.

In the method for producing the cosmetic of the present invention,
The amount of the biodegradable polyester resin fine particles or the biodegradable polyester resin composite fine particles added is 0.1 to 99% by mass in the cosmetic product in terms of components other than water (solid content conversion).
Is preferable, and it is particularly preferable that the amount is in the range of 0.5 to 90 mass%. This is, when the added amount of the biodegradable polyester resin fine particles or the biodegradable polyester resin composite fine particles exceeds the upper limit of the above range,
This is because the effect as a cosmetic tends to be lost,
On the other hand, when the content is less than the lower limit of the above range, the effect of addition is small, and improvement in the feeling of use of cosmetics by blending the fine particles tends to be difficult to achieve.

[0051]

EXAMPLES The present invention will be specifically described below with reference to examples. The analysis of each of the following items was performed according to the methods described below. (1) Molecular weight of biodegradable polyester resin The molecular weight was determined by GPC analysis (refractive index spectrometer manufactured by Shimadzu Corporation, solvent: tetrahydrofuran, converted to polystyrene). (2) Measurement of content rate of lactic acid unit in resin component of fine particles It was determined by dissolving fine particles in D-chloroform and performing NMR measurement (Lambda 300WB manufactured by JEOL Ltd.) at room temperature. (3) Measurement of D-form content in lactic acid unit of fine particles The fine particles were dissolved in chloroform, and a Na-D line (589) was obtained using a polarimeter (SEPA-200 manufactured by Horiba Ltd.).
nm), and the specific optical rotation is determined at 25 ° C., and the D amount (mol%)
Was calculated. (4) Measurement of the major axis and the minor axis of fine particles If the particle size is 5 μm or more, use an optical microscope (OLYMPU
It was measured at a magnification of 500 times using S-10 PM-10AK). If the particle size is less than 5 μm, a scanning electron microscope (S-4000 manufactured by Hitachi, Ltd.) is used and the magnification is 20.
It was measured at 00 to 5000 times. Then, a certain number of objects existing in the field of view of the microscope (in Table 1 below, "measurement target"
The ratio of the major axis to the minor axis is 1.5.
By counting the number of the following items, we calculated what percentage of the total number. (5) Density of fine particles A density gradient tube was prepared using a saline solution, and the density standard tube was calibrated and measured. (6) 10% deformation strength of fine particles After observing the fine particles one by one with a microscope to measure the particle size, a test load of 49 mN and a load speed of 0.89 mN were obtained using a micro compression tester (MCTM-500 manufactured by Shimadzu Corporation). The strength was measured at / s. The compressive load when the particle diameter was changed by 10% was defined as 10% deformation strength. Each sample was measured 10 times, and the average value was adopted. (7) Average particle size of fine particles The particle size was measured using a particle size distribution measuring device (LA920, manufactured by Horiba Ltd.), and the volume average particle size was evaluated. (8) Quantitative HPLC method for the amount of lactic acid in cosmetics (column: Amix HPX-87P length 300 mm × diameter 7.8 mm, mobile phase: 0.005 N sulfuric acid, detection: RI, temperature: 60 ° C., flow rate: 0.6 ml / M
in, injected sample: 100 μl. The standard sample was quantified with 1/500 diluted aqueous solution of lactic acid (special grade reagent, manufactured by Ishizu Pharmaceutical Co., Ltd.). The amount of lactic acid was measured for the cosmetics after being placed in an atmosphere of 30 ° C. for 1 month. (9) Evaluation of cosmetics A sensory test was conducted by 20 panelists. Feeling and slippage were selected as the evaluation items in this test, and each item was evaluated on a scale of 5 according to the following criteria. 1 ... bad, 2 ... bad, 3 ... normal, 4 ... good, 5
… Good Also, the pH condition of the skin when applying cosmetics
H meter-PH900 (Courage + Khazaka electronic GmbH
(Manufactured by the company).

First, biodegradable polyester resin fine particles (A) to (H) were obtained in the following manner.

Fine particles (A) Water content as a biodegradable polyester resin is 200 p
Polylactic acid dried to pm (number average molecular weight 60,000,
40 parts by mass of D-form content (1.7 mol%) and polyacrylic acid (weight average molecular weight 100,000) as a dispersion medium.
After dry blending with 60 parts by mass, the mixture was fed to the feed port of the same-direction twin-screw extruder (PCM-30 manufactured by Ikegai Tekko KK). Melt-kneading was performed with the cylinder temperature of the extruder set at 180 ° C., and the resin composition was extruded from the nozzle and solidified by cooling. After that, the polyacrylic acid is dissolved with 10 times the mass of water with respect to the polyacrylic acid, and the diameter is about 10 μm.
A suspension of spherical polylactic acid particles was obtained. The suspension was centrifuged and dried to obtain biodegradable polyester resin fine particles (A).

Fine particles (B) Water content as a biodegradable polyester resin is 200 p
Polylactic acid dried to pm (number average molecular weight 60,000,
40 parts by mass of D-form content (1.7 mol%), 4 parts by mass of zinc oxide fine powder as a compounding compound for forming fine particles of fine particles, and polyethylene glycol (manufactured by Sanyo Kasei Co., Ltd.) as a dispersion medium. P20000) 60 parts by mass, and then mixed in the same direction with a twin-screw extruder (P.
It was supplied to the supply port of CM-30). Melt-kneading was performed with the cylinder temperature of the extruder at 200 ° C., and the resin composition was extruded from the nozzle and cooled and solidified. Then, the polyethylene glycol was dissolved using 10 times the mass of water with respect to polyethylene glycol to obtain a suspension of zinc oxide-containing polylactic acid spherical particles having a diameter of about 10 μm. The suspension was centrifuged and dried to obtain biodegradable polyester resin composite fine particles (B).

Fine Particles (C) Polylactic acid having a number average molecular weight of 100,000 and a D-form content of 9 mol%, which was dried to a water content of 200 ppm, was used. A pressure kneading device (PK5 manufactured by Moriyama Seisakusho) was used instead of the same-direction twin-screw extruder. Other than that, biodegradable polyester resin fine particles (C) were obtained in the same manner as in the case of fine particles (A).

Fine Particles (D) Polylactic acid having a number average molecular weight of 100,000 and a D-form content of 19 mol%, which was dried to a water content of 200 ppm, was used. In addition, the cylinder temperature of the twin-screw extruder is 170
℃ was made. Then, in the same manner as in the case of the fine particles (A) except the above, biodegradable polyester resin fine particles (D) were obtained.

Fine particles (E) As a biodegradable polyester resin, water content is 200 pp
Polylactic acid dried to m (number average molecular weight 100,000,
D-form content 19 mol%) 1.8 kg and polycaprolactone (number average molecular weight 80,000) 0.2 as a complex compound
It was used by mixing with kg. Then, the cylinder temperature of the twin-screw extruder was set to 160 ° C. Then, in the same manner as in the case of the fine particles (A) except the above, biodegradable polyester resin fine particles (E) were obtained.

Fine particles (F) As the compounding compound, fine titanium white powder was used instead of the zinc oxide powder. Then, other than that, in the same manner as in the case of the fine particles (B), biodegradable polyester resin composite fine particles (F) were obtained.

Fine particles (G) Starch powder (potato) was used as the complexing compound instead of zinc oxide powder. Then, other than that, the biodegradable polyester resin composite fine particles (G) were obtained in the same manner as the case of the fine particles (B).

Fine particles (H) As the composite compound, fine ferrite particles were used instead of the zinc oxide powder. And, other than that, fine particles (B)
Biodegradable polyester resin composite fine particles (H) were obtained in the same manner as in the above.

Example 1 20 parts by mass of biodegradable polyester resin fine particles (A), p
5 parts by mass of octyl methoxycinnamate, 1 part by mass of α-monoisostearyl glyceryl ether polyoxyethylene sorbitan monooleate as fatty acid ester, 2 parts by mass of beeswax as waxes, 2 parts by mass of lanolin as waxes, Squalane as a hydrocarbon 20
Parts by mass, 30 parts by mass of liquid paraffin as hydrocarbon,
19 parts by mass of purified water, an appropriate amount of preservative, and an appropriate amount of perfume were put into a homodisper and stirred at 2500 rpm for 3 minutes to prepare a milky cosmetic.

Example 2 30 parts by mass of biodegradable polyester resin composite fine particles (B), 5 parts by mass of octyl p-methoxycinnamate, 1 part by mass of α-monoisostearyl glyceryl ether polyoxyethylene sorbitan monooleate, beeswax Two
Parts by mass, 2 parts by mass of lanolin, 20 parts by mass of squalane, 20 parts by mass of liquid paraffin, 19 parts by mass of purified water, an appropriate amount of preservative, and an appropriate amount of perfume were put into a homodisper, and 250
The emulsion cosmetic was prepared by stirring at 0 rpm for 3 minutes.

Example 3 30 parts by mass of biodegradable polyester fine particles (C), 5 parts by mass of octyl p-methoxycinnamate, 1 part by mass of α-monoisostearyl glyceryl ether polyoxyethylene sorbitan monooleate, 2 parts by mass of beeswax. Parts, 2 parts by weight of lanolin, 20 parts by weight of squalane, 20 parts by weight of guar gum as a thickener, 19 parts by weight of purified water, an appropriate amount of preservative, and an appropriate amount of perfume are added to a homodisper, and 250
The emulsion cosmetic was prepared by stirring at 0 rpm for 3 minutes.

Example 4 30 parts by mass of biodegradable polyester resin fine particles (D) were used. Then, an emulsion cosmetic was prepared in the same manner as in Example 3 except for the above.

Example 5 30 parts by mass of biodegradable polyester resin fine particles (E) were used. Then, an emulsion cosmetic was prepared in the same manner as in Example 3 except for the above.

Example 6 30 parts by mass of biodegradable polyester resin composite fine particles (F) were used. Then, other than that, in the same manner as in Example 3,
An emulsion cosmetic was prepared.

Example 7 30 parts by mass of biodegradable polyester resin composite fine particles (G) were used. Then, other than that, in the same manner as in Example 3,
An emulsion cosmetic was prepared.

Example 8 30 parts by mass of biodegradable polyester resin composite fine particles (H) were used. Then, other than that, in the same manner as in Example 3,
An emulsion cosmetic was prepared.

Comparative Example 1 1 kg of polylactic acid (number average molecular weight 60,000, D-form content 1.7 mol%) dried to a water content of 200 ppm,
After dissolving in 10 kg of methylene chloride, the mixture was poured into water with stirring to obtain a suspension of polylactic acid spherical particles. This was centrifuged and dried to obtain biodegradable polyester resin fine particles (a). 30 parts by mass of the fine particles (a) were used instead of the fine particles (C). Then, an emulsion cosmetic was prepared in the same manner as in Example 3 except for the above.

Comparative Example 2 As polylactic acid, polylactic acid (number average molecular weight 100,000, D-form content 9 mol%) dried to a water content of 200 ppm was used. Then, in the same manner as in Comparative Example 1 except for the above, biodegradable polyester resin fine particles (b) were obtained. 30 parts by mass of the fine particles (b) were used instead of the fine particles (a). Then, an emulsion cosmetic was prepared in the same manner as in Example 3 except for the above.

Comparative Example 3 As polylactic acid, 250 g of polylactic acid that had been dried to a water content of 200 ppm and partially depolymerized (number average molecular weight 20,000, D-form content 9 mol%) was used. This was swollen with 100 g of isopropyl alcohol. Then, the swollen polylactic acid and P as a surfactant are added.
VA (Unitika, UF170G) 2 mass% aqueous solution 10
0 g, distilled water 550 g, and triethylamine corresponding to 1.2 times the equivalent amount of all carboxyl groups contained in the polylactic acid were added, and the mixture was forcibly stirred at 6,000 rpm.
Furthermore, the temperature in the system is raised to 60 ° C., stirring is continued,
An emulsion was obtained. This was centrifuged and dried to obtain biodegradable polyester resin fine particles (c). 30 parts by mass of the fine particles (c) were used instead of the fine particles (C). Then, an emulsion cosmetic was prepared in the same manner as in Example 3 except for the above.

Comparative Example 4 Polylactic acid having a water content of 1200 ppm (number average molecular weight 6
The content of D-form was 1.7 mol%. Then, other than that, the biodegradable polyester resin fine particles (d) were obtained in the same manner as in the case of the polyester resin fine particles (A). This fine particle (d) was used instead of the fine particle (A). Then, an emulsion cosmetic was prepared in the same manner as in Example 1 except for the above.

Regarding Examples 1 to 8 and Comparative Examples 1 to 4,
Various measurements were performed on biodegradable polyester resin fine particles and cosmetics. The results are shown in Table 1. Regarding the results of evaluation as cosmetics and the results of measuring the skin pH state, Examples 1 to 6 are shown in Table 2 and Example 7 is shown.
8 and Comparative Examples 1 to 4 are collectively shown in Table 3.

[0074]

[Table 1]

[0075]

[Table 2]

[0076]

[Table 3]

As is clear from the results of Tables 1 to 3, in the cosmetics of Examples 1 to 8 of the present invention, the biodegradable polyester resin fine particles or the biodegradable polyester resin composite fine particles have predetermined characteristics. As a result, the obtained cosmetic had excellent feel and slipperiness when applied to the skin.

On the other hand, the cosmetics of Comparative Examples 1 to 3 were not those in which the fine particles were produced by melt-kneading the raw materials under the high shear condition unlike the cosmetics of Examples 1 to 8. , The deformation strength of the fine particles when compressed is low, so that the fine particles are deformed when used as a cosmetic,
Therefore, it was inferior in touch to the skin and in slipperiness during application. The cosmetic of Comparative Example 4 has a moisture content of 1200 ppm.
Since a large amount of lactic acid monomer remains in the produced fine particles because the polylactic acid of 1. was used, the lactic acid concentration contained in the obtained cosmetic product was 1500 ppm, which was not a preferable cosmetic product.

[0079]

The cosmetics of the present invention have extremely high strength of fine particles, and are very effective in improving the feel and the slipperiness when applied to the skin. Moreover, the fine particles can be easily and inexpensively produced without using an organic solvent and without using special equipment or complicated operations.

Continued front page    F term (reference) 4C083 AD091 BB24 EE03 EE06                       FF01

Claims (4)

[Claims] 1. A cosmetic comprising fine particles and another cosmetic raw material, wherein the fine particles contain 5 lactic acid units in a resin component.
It is formed of a biodegradable polyester resin containing 0 mol% or more and a D-form content in the lactic acid unit of 0.1 to 25 mol%, and 70% or more of the total number of the fine particles has a long diameter and a short diameter. The ratio of the diameters satisfies (major axis) / (minor axis) ≦ 1.5, the density is 1.0 to 10.0 g / cm ³ , the average particle diameter is 0.01 to 1000 μm, and at the time of compression. Of 1
A cosmetic product having a 0% deformation strength of 5 MPa or more. 2. The cosmetic product according to claim 1, which contains 0.1 to 1000 ppm of lactic acid. 3. The fine particles, based on 100% by volume as a whole, contain 1 to 95% by volume of at least one component selected from an inorganic substance and / or an organic substance in addition to a biodegradable polyester resin. Claim 1 characterized by the above-mentioned.
The listed cosmetics. 4. A biodegradable polyester resin having a lactic acid unit content of 50 mol% or more and a D-form content in the lactic acid unit of 0.1 to 25 mol% is used. Of 1000 ppm or less, the melt-kneading method is applied to the dried resin to produce fine particles, and the fine particles are added to other cosmetic raw materials. Cosmetic manufacturing method.