JP5261678B2 - Spherical polymer fine particle-coated plate-like powder and cosmetic containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a platy powder coated with spherical polymer microparticles having soft focus functions and optical anisotropy functions, and to provide a cosmetic including the platy powder coated with the spherical polymer microparticles. <P>SOLUTION: The surface of a platy powder is coated with the spherical polymer microparticles having a shell of polyethylene glycol on the outside by dispersing a compound represented by general formula (1) (wherein, m and n represent each an integer of &ge;1) in the presence of the platy powder in a solution, subsequently adding a radically polymerizable monomer, and carrying out dispersion polymerization. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a spherical polymer fine particle-coated plate-like powder formed by coating spherical polymer fine particles on the surface of a plate-like powder, and a cosmetic containing the plate-like powder.

  Conventionally, in powder cosmetics represented by powder foundation, pigments with high hiding power such as titanium dioxide, bengara, yellow iron oxide, organics are used to make the skin color and freckles less visible and to adjust the skin color. A pigment having a high refractive index such as a dye or a pigment having a high coloring power is blended.

  However, the cosmetic finish of the above-mentioned conventional powder cosmetics has a problem that although it can cover the defects of the skin, it has a matte finish with no gloss, resulting in an unnatural-looking cosmetic skin. Therefore, a method has been adopted in which an appropriate amount of a pearl pigment having a strong luster such as titanium mica is blended to impart luster. There was a tendency to have an unnatural finish that was different from luster.

  For these reasons, there is a strong demand for the development of makeup cosmetics that cover skin defects such as skin spots and freckles and have a natural finish close to the bare skin.

  On the other hand, attempts have been made to suppress strong gloss by coating a pearl pigment such as titanium mica with a spherical powder. For example, Patent Document 1 proposes a technique in which spherical fine particles of acrylic resin are attached to the surface of a pearl pigment such as mica titanium by spray drying a slurry in which fine particles of acrylic resin are dispersed. . Patent Document 2 proposes a technique in which a plate-like powder and an organic spherical powder are mechanically dry blended so that the plate-like powder is coated with the organic spherical powder.

  However, those described in any of these documents have a defect that adhesion is weak because only spherical fine particles are attached to the surface of the pearl pigment.

Japanese Patent Laid-Open No. 9-48707 Japanese Patent Laid-Open No. 9-12430

  The present invention has been made in view of such problems, and by coating spherical polymer fine particles having a polyethylene glycol shell on the surface of a plate-like powder by a dispersion polymerization method, the soft focus function and optical anisotropy are achieved. It is a first object of the present invention to provide a spherical polymer fine particle-coated plate-like powder having a sexual function, and to provide a cosmetic containing the fine spherical polymer fine particle-coated plate-like powder.

  The present invention also provides a plate-like powder of spherical methyl methacrylate fine particles by copolymerizing a silane coupling agent having a polymerizable functional group such as a vinyl group or a methacryloxy group with a radical polymerizable monomer such as methyl methacrylate. It is a second object of the present invention to provide a spherical polymer fine particle-coated plate-like powder having improved adhesion to the body and to provide a cosmetic containing the fine spherical polymer fine particle-coated plate powder. is there.

As a result of intensive studies to achieve the above-mentioned problems, the present inventors have adsorbed a polymer azo initiator represented by the following general formula (1) in a plate-like powder in a solution, and further methacrylic acid. The inventors have found that a spherical polymer fine particle-coated plate-like powder obtained by adding a radical polymerizable monomer such as methyl and carrying out dispersion polymerization achieves the above object, and has completed the present invention.
In short, the spherical polymer fine particle-coated plate-like powder according to the first invention is
In the presence of a plate-like powder, the compound represented by the general formula (1) is dispersed in a solution, and then a radical polymerizable monomer is added and subjected to dispersion polymerization to have a polyethylene glycol shell on the outside. A spherical polymer fine particle is coated on the surface of a plate-like powder.

  In the first invention, the plate-like powder is preferably pretreated with a polymerizable silane coupling agent in advance (second invention). Alternatively, it is preferable to add a polymerizable silane coupling agent simultaneously with the radical polymerizable monomer (third invention).

  The cosmetic according to the fourth invention is characterized by containing the spherical polymer fine particle-coated plate-like powder according to any one of the first to third inventions.

According to the first invention, when a polymer azo initiator is adsorbed to a plate-like powder in a solution, a radical polymerizable monomer is added, and polymerization is started while blowing N ₂ gas, It becomes possible to coat the surface of the plate-like powder with spherical polymer fine particles having a polyethylene glycol shell on the outside having a uniform particle diameter. Thus, a spherical polymer fine particle-coated plate-like powder having an excellent soft focus effect can be obtained.

According to the second and third inventions, the plate-like powder is pretreated with a silane coupling agent having a polymerizable functional group, and the obtained plate-like powder is mixed with a polymer azo initiator and a radical polymerizable monomer. Addition to start polymerization while blowing N ₂ gas (second invention) or silane cup having plate powder, polymer azo initiator, radical polymerizable monomer and polymerizable functional group in solution When a ring agent is added at the same time and polymerization is started while N ₂ gas is blown (third invention), a spherical shape coated on the plate-like powder and the surface by the silane coupling agent chemically bonded to the plate-like powder. Adhesion with polymer fine particles can be increased.

  According to the fourth aspect of the invention, since the spherical polymer fine particle-coated plate-like powder is blended in the cosmetic, a cosmetic having a sense of transparency, good touch, and having a soft focus function and an optical anisotropy function is obtained. be able to.

  Next, specific embodiments of the spherical polymer fine particle-coated plate-like powder and the cosmetics containing the same according to the present invention will be described.

２）所定温度にてラジカル重合性モノマーを添加し、Ｎ_２ガスを吹き込んで重合を開始させ、攪拌を続ける。
３）必要に応じて水洗、ろ過する。 The spherical polymer particle-coated plate-like powder of the present invention is produced by the following procedure.
1) A polyethylene glycol (PEG) -containing macroazo polymerization initiator represented by the following general formula (1) is completely dissolved in a solvent, and then a plate-like powder is dispersed to obtain a polyethylene glycol (PEG) -containing macroazo polymerization. The initiator is adsorbed on the plate-like powder.

2) A radical polymerizable monomer is added at a predetermined temperature, and N ₂ gas is blown to initiate polymerization, and stirring is continued.
3) Wash with water and filter if necessary.

  The plate-like powder used in the present invention is a plate-like powder made of natural or artificial clay mineral, and examples thereof include sericite, talc, mica, plate-like barium sulfate, and mica titanium.

  Moreover, as an example of the compound shown by the said General formula (1) used by this invention, the brand names VPE-0201, VPE-0401, VPE-0601 which are marketed from Wako Pure Chemical Industries Ltd. are mentioned. .

  As the radical polymerizable monomer used in the present invention, monomers used in usual radical polymerization such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, styrene, and acrylate can be used.

  A method for producing spherical polymer fine particles by using a polyethylene glycol-containing macroazo initiator and a hydrophobic vinyl-based monomer by dispersion polymerization in alcohol mixed with water has already been disclosed in JP-A-2006-257139. . The present invention makes it possible to adsorb a polyethylene glycol-containing macroazo initiator to a plate-like powder, add a radically polymerizable monomer and perform dispersion polymerization, and adsorb spherical polymer fine particles to the plate-like powder. is there.

  In the present invention, a dispersion polymerization method in a system that does not contain a surfactant other than a polyethylene glycol-containing macroazo initiator is used, and the initiator itself has a polymerization initiation site. There is no need to use a polymerization initiator, and there is no need to take out a surfactant as in a general emulsion polymerization method. Here, water and alcohol are used as a dispersion polymerization medium. The water is preferably ion-exchanged water that does not contain salt. Moreover, as alcohol, it is suitable to use C1-C4 alcohol, such as ethanol, methanol, n-propanol, and t-butanol. In addition, as a preferable medium, what has water as a main component is good, and the volume ratio (water / alcohol) of water and alcohol is about 95 / 5-20 / 80, More preferably, 90 / 10-30 / 70. It is good to use a mixed medium.

  In the present invention, when methyl methacrylate is used as a monomer, the molar ratio of the polyethylene glycol-containing macroazo initiator represented by the above general formula (1) to the methyl methacrylate (mol of the polyethylene glycol moiety of the general formula (1)) Number / number of moles of methyl methacrylate) is preferably in the range of 1/20 to 1/500, more preferably in the range of 1/50 to 1/300. If the denominator of this molar ratio is larger than 500, the influence of the polyethylene glycol chain as a surfactant is inferior, and there is a concern that polymethyl methacrylate fine particles will not be formed. Further, when this denominator is smaller than 20, the solubility in a solvent is improved, so that there is a concern that polymethyl methacrylate fine particles are not formed. Further, the coating amount of the polymethyl methacrylate fine particles is preferably in the range of 1 to 100%, more preferably in the range of 2 to 40% with respect to the base plate-like powder. When the coating amount of the polymethyl methacrylate fine particles is increased, the polymethyl methacrylate fine particles that are not coated on the base plate-like powder are present in a free state, and thus the productivity is deteriorated.

  The particle size of the polymer fine particles such as polymethyl methacrylate coated on the plate-like powder can be confirmed by an electron microscope, and spherical or hemispherical polymer fine particles having a relatively uniform particle diameter of about 50 nm to 500 nm are formed into plate-like powder. It is coated on the body surface.

  As a method for producing the spherical polymer fine particle-coated plate-like powder according to the present invention, a suspension polymerization method can be used in addition to the dispersion polymerization method. The particle size of the spherical polymer fine particles can be adjusted to 1 μm or less in the diameter by the dispersion polymerization method and from 1 μm to 500 μm in the diameter by the suspension polymerization method.

  In the spherical polymer fine particle-coated plate-like powder according to the present invention, the molecular weight of the coated spherical polymer fine particles is preferably measured using a gel permeation chromatograph (GPC).

  Examples of the silane coupling agent having a vinyl group or methacryloxy group according to the present invention include vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltrimethoxysilane, and methacryloxypropyltriethoxysilane. These are chemically bonded to the OH group of the inorganic plate-like powder by hydrolysis and polycondensation, and can be polymerized with monomers such as methyl methacrylate.

  In the present invention, examples of the evaluation method of the soft focus function include a haze / transmittance meter, a variable angle spectrocolorimetry system, and a three-dimensional variable angle photometer. It is preferable to use a method of measuring the light rate.

In the present invention, the spherical polymer fine particle-coated plate-like powder can be further subjected to various surface treatments known per se. Examples of this surface treatment include the following treatments. A combination of these processes can also be used.
a) Fluorine compound treatment: perfluoroalkyl phosphate treatment, perfluoroalkylsilane treatment, perfluoropolyether treatment, fluorosilicone treatment, fluorinated silicone resin treatment, etc.
b) Silicone treatment: methylhydrogenpolysiloxane treatment, dimethylpolysiloxane treatment, vapor phase tetramethyltetrahydrogencyclotetrasiloxane treatment, etc.
c) Pendant treatment: a method of adding an alkyl chain or the like after the gas phase method silicone treatment.
d) Silane coupling agent treatment e) Titanium coupling agent treatment f) Aluminum coupling agent treatment g) Oil agent treatment h) N-acylated lysine treatment i) Polyacrylic acid treatment j) Metal soap treatment... Stearate Treatment, misty phosphate treatment, etc. k) Acrylic resin treatment l) Metal oxide treatment

  The spherical polymer fine particle-coated plate-like powder of the present invention has a good feeling when used in cosmetics, has a feeling of transparency and a texture similar to that of the skin, and has an effect of making the unevenness, fine lines and blotches of the skin inconspicuous. A cosmetic with a certain amount can be obtained. In this case, as a compounding quantity, 0.1-100 mass% is preferable, More preferably, it is 0.5-60 mass%. As the cosmetic dosage form, conventionally known dosage forms such as a bilayer, a water-in-oil emulsion, an oil-in-water emulsion, a gel, a spray, a mousse, an oil, and a solid can be used. Of course, in order to obtain the cosmetic of the present invention, other known color pigments, extender pigments, resin powders, glitter powders, or surface treated powders thereof are combined with surfactants and oils. Needless to say, you can.

  Next, specific examples of the spherical polymer fine particle-coated plate-like powder according to the present invention and cosmetics containing the same will be described. In addition, this invention is not limited to the Example described below.

(Powder Preparation Example 1)
Introducing a macroazo polymerization containing polyethylene glycol, which is commercially available under the name VPE-0201 from Wako Pure Chemical Industries, Ltd. in a 200 ml four-necked flask equipped with a Dimroth condenser, thermometer, and N ₂ gas inlet tube After adding 0.35 g of the agent and dissolving it, 6 g of sericite commercially available under the name of sericite FSE from Sanshin Mining Co., Ltd. was added and allowed to stand overnight. Thereafter, 60 ml of water and 5.3 ml of methyl methacrylate were added, N ₂ gas was blown in, polymerization was started at 75 ° C., and stirring was continued for 15 hours. After completion of stirring, sericite FSE was allowed to settle, and the supernatant was removed and dried under reduced pressure at 35 ° C. to obtain spherical polymethyl methacrylate (PMMA) fine particle-coated sericite.

(Powder Preparation Example 2)
In the same manner as in Example 1 except that the sericite FSE in powder preparation Example 1 was changed to titanium mica commercially available from Merck under the name Timiron Starluster MP-115 (particle size of about 10 μm). Methyl methacrylate (PMMA) fine particle-coated titanium mica was obtained.

(Powder Preparation Example 3)
In the same manner as in Example 1, except that the sericite FSE in powder preparation Example 1 was changed to titanium mica commercially available from ECKART under the name of PRESTAGE Bright Gold (particle size of about 15 to 70 μm). Methyl methacrylate (PMMA) fine particle-coated titanium mica was obtained.

(Powder Preparation Example 4)
Introducing a macroazo polymerization containing polyethylene glycol, which is commercially available under the name VPE-0201 from Wako Pure Chemical Industries, Ltd. in a 200 ml four-necked flask equipped with a Dimroth condenser, thermometer, and N ₂ gas inlet tube After adding 0.35 g of the agent and dissolving it, 6 g of sericite commercially available under the name of sericite FSE from Sanshin Mining Co., Ltd. was added and allowed to stand overnight. Thereafter, 60 ml of water, 5.3 ml of methyl methacrylate, and 1.0 ml of methacryloxypropyltriethoxysilane were added simultaneously, N ₂ gas was blown into the reactor, polymerization was started at 75 ° C., and stirring was continued for 15 hours. After completion of stirring, sericite FSE was allowed to settle, and the supernatant was removed and dried under reduced pressure at 35 ° C. to obtain spherical polymethyl methacrylate (PMMA) fine particle-coated sericite.

(Powder preparation comparative example 1)
In a 200 ml four-necked flask equipped with a Dimroth condenser, a thermometer, and an N ₂ gas introduction tube, 100 ml of ethanol / water = 2: 3 (volume ratio) mixed solvent and 2,2′-azobis (polymerization initiator) After adding and dissolving 0.05 g of isobutyronitrile, 6 g of sericite commercially available under the name of sericite FSE from Sanshin Mining Co., Ltd. was added and stirred for 1 hour. Thereafter, 5.3 ml of methyl methacrylate was added, N ₂ gas was blown in, polymerization was started at 75 ° C., and stirring was continued for 15 hours. After completion of stirring, sericite FSE was allowed to settle, and the supernatant was removed and dried under reduced pressure at 35 ° C. to obtain polymethyl methacrylate (PMMA) -coated sericite.

  Table 1 shows the total transmitted light rate Tt (%), diffuse transmitted light rate Td (%), and haze value H (%) for the powder preparation examples 1 and 4 and the powder preparation comparative example 1. The result of comparing the values is shown.

Here, the haze value was measured as follows. That is, 0.4 g of the obtained powder is dispersed in 1.6 g of silicone marketed by Toray Dow Corning under the name SF8417, and a Hoover Mara (100 rpm × 3 times) is used to prepare a paste. And the sample apply | coated so that the film thickness of a paste might be set to 25 micrometers on a glass plate is measured using a haze and a transmissometer. The haze value is expressed by the following formula: haze value (H) = diffuse transmitted light rate (Td) / total transmitted light rate (Tt) × 100
The greater the total transmitted light rate (Tt) value, the greater the amount of transmitted light, indicating that there is a sense of transparency, and the greater the diffuse transmitted light rate (Td) value, the greater the amount of scattered light. The blur effect is high, and the larger the haze value (H) is, the soft focus effect is.

  From the results of Table 1, the value of the total transmittance Tt of the powder preparation Example 1 containing the polyethylene glycol-containing macroazo polymerization initiator is 90.0%, which is compared with 89.1% of the powder preparation comparative example 1. It can be seen that the value is high and the transparency is excellent. Further, the value of the diffuse transmission light transmittance Td of the powder preparation example 1 is also 58.6%, which is higher than the 44.3% of the powder preparation comparative example 1, and fine wrinkles and blotches are observed. It can be seen that the effect of blurring is excellent. Further, the haze value H of the powder preparation example 1 is also 65.2%, which is a higher value than the 49.7% of the powder preparation comparative example 1, and the soft focus feeling is excellent. I understand that. In the powder preparation comparative example 1, the film of polymethyl methacrylate is coated on the surface of the plate-like powder, whereas in the powder preparation example 1, spherical polymethacrylic acid with relatively uniform particles is used. This is probably because the fine particles are coated on the powder surface, so that the soft focus effect is excellent. Moreover, the haze value H of the powder preparation example 4 which improved adhesiveness by adding and copolymerizing the silane coupling agent which has a polymeric functional group with methyl methacrylate is 66.5%, Compared to 49.7% of the powder preparation comparative example 1, it is a higher value, which indicates that the soft focus feeling is more excellent.

(Cosmetic preparation example 1)
A powder foundation was obtained according to the formulation shown in Table 2.

(Cosmetic preparation example 2)
A powder foundation was obtained according to the formulation shown in Table 3.

(Cosmetic preparation example 3)
A powder foundation was obtained according to the formulation shown in Table 4.

(Cosmetic preparation comparative example 1)
A powder foundation was obtained in the same manner as in Cosmetic Preparation Example 1, except that the spherical PMMA-coated sericite FSE was changed to 55 mass% sericite FSE and 5 mass% spherical PMMA in the cosmetic preparation example 1. .

(Cosmetic preparation comparative example 2)
In the cosmetic preparation example 2, the spherical PMMA-coated titanium mica was changed to 8 mass% titanium mica (Timiron Starluster MP-115) and 2 mass% spherical PMMA in the same manner as the cosmetic preparation example 2. A powder foundation was obtained.

(Cosmetic preparation comparative example 3)
In the cosmetic preparation example 3, the spherical PMMA-coated titanium mica was changed to 8 mass% titanium mica (Timiron Starluster MP-115) and 2 mass% spherical PMMA in the same manner as the cosmetic preparation example 3. A powder foundation was obtained.

(Evaluation of powder foundation)
Ten female panelists use each of the above powder foundations, and each of the powder foundations of the cosmetic preparation example 1 and the cosmetic preparation comparative example 1 has a sense of transparency and soft focus, and the cosmetic preparation. For each of the powder foundations of Examples 2 and 3 and Cosmetic Preparation Comparative Examples 2 and 3, they were each answered in a questionnaire format with a sense of transparency, lack of glare and soft focus. An evaluation result was obtained with an average score of panelists, with 0 points for poor evaluation and 5 points for good evaluation. These evaluation results are shown in Tables 5 and 6. In these tables, the higher the score, the better the evaluation.

  From the results of Table 5, cosmetic preparation Example 1 in which spherical polymethyl methacrylate (PMMA) fine particle-coated sericite FSE was blended in a powder foundation was more transparent and soft-focused compared to Cosmetic Preparation Comparative Example 1. It turns out that both are excellent.

  Further, from the results of Table 6, cosmetic preparation examples 2 and 3 in which the spherical polymethyl methacrylate (PMMA) -coated titanium mica of powder preparation examples 2 and 3 were blended in the powder foundation were compared with cosmetic preparation comparative example 2. Compared with, 3, it can be seen that it has the effect of reducing the glare peculiar to pearl pigments, resulting in a natural cosmetic finish, and also has a transparent feeling and soft focus feeling. It turns out that there is also an effect that a close makeup finish is achieved. Titanium mica blended in Cosmetic Preparation Comparative Example 3 has a relatively large particle size, so when blended into a powder foundation, it feels glistening and produces an unnatural cosmetic finish. In the case of Example 3, since it has a moderate gloss and the glare characteristic peculiar to the pearl pigment is suppressed, it can be seen that the result is natural.

Claims (4)

In the presence of a plate-like powder, the compound represented by the general formula (1) is dispersed in a solution, and then a radical polymerizable monomer is added and subjected to dispersion polymerization to have a polyethylene glycol shell on the outside. A plate-like powder coated with spherical polymer particles, wherein the plate-like powder surface is coated with spherical polymer particles.

  The plate-like powder coated with spherical polymer particles according to claim 1, wherein the plate-like powder is pretreated with a polymerizable silane coupling agent in advance.   The spherical polymer fine particle-coated plate-like powder according to claim 1, wherein a polymerizable silane coupling agent is added simultaneously with the radical polymerizable monomer.   A cosmetic comprising the spherical polymer fine particle-coated plate-like powder according to any one of claims 1 to 3.