JP7436967B2 - Spherical composite powder for cosmetics and method for producing the same - Google Patents

Description

The present invention relates to an environmentally compatible spherical composite powder for cosmetics that has high sphericity and soft touch characteristics, and a method for producing the same.

In recent years, the negative impact on the environment and ecosystem caused by the outflow of plastic waste into the ocean has come to the fore and has attracted worldwide attention (Non-Patent Document 1). In particular, synthetic polymer particles with a particle diameter of 5 mm or less are commonly referred to as plastic microbeads (hereinafter referred to as PMB), and are becoming subject to regulations in many countries.

In the field of cosmetics, scrubbing agents (PMB with a median diameter of several hundred μm) that are incorporated into facial cleansers etc. were first subject to regulation, and domestic companies are replacing them with naturally derived particles such as cellulose (Non-patent Document 2). ).

On the other hand, pressed foundation (hereinafter referred to as PF) contains spherical powder made of synthetic polymer such as nylon or polyurethane with a median diameter of about 10 μm for the purpose of improving the feel. Since this PMB has unique rolling properties and softness, it has a large influence on the tactile characteristics of PF formulations, and it is currently very difficult to substitute it with other raw materials.

Spherical silica and spherical cellulose are examples of alternative raw materials for PMB contained in PF. Spherical cellulose having a porous structure through particle morphology control has been disclosed (Patent Documents 1 and 2). However, all of them had a harder feel than the above synthetic polymers and were not satisfactory as alternative raw materials.

Against this background, there is a potential desire to develop a spherical powder for cosmetics that is environmentally compatible and soft to the touch and can replace conventional synthetic polymers (PMB).

Japanese Patent Application Publication No. 1994-136175 Japanese Patent Application Publication No. 1985-197746

Koshien University Bulletin No. 45, p37-44 (2018) Current status and challenges of marine pollution caused by plastics, especially regarding microplastics Japan Cosmetic Industry Federation Voluntary Standards Notification Document Announced on March 17, 2016 Regarding the use of microplastic beads in wash-off scrub products

The present invention has been made in view of the above circumstances, and aims to provide a spherical composite powder for cosmetics that has high sphericity, is soft to the touch, and is environmentally compatible, and a method for producing the same.

Under these circumstances, the inventors of the present application have conducted extensive research to solve the above problems, and have found that aggregate particles composed of specific minerals and water-soluble polysaccharides are highly spherical and have a soft texture for use in cosmetics. It was discovered that it can be used as a spherical composite powder and has tactile properties that can be used as a substitute for conventional synthetic polymers (PMB), leading to the completion of the present invention.

The present invention provides a spherical composite powder for cosmetics, which is characterized by containing a mineral having a specific median diameter and a water-soluble polysaccharide, and a method for producing the same.

The present invention provides a spherical composite powder for cosmetics that has high sphericity, is soft to the touch, and is environmentally compatible, and a method for producing the same.

Electron microscope image of the spherical composite powder for cosmetics obtained in Example 1

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The spherical composite powder for cosmetics, which has high sphericity, is soft to the touch, and is environmentally compatible, and the method for producing the same, according to the present invention, will be described below based on preferred embodiments thereof. According to the present invention, it is possible to obtain a spherical composite powder for cosmetics that can replace a conventional synthetic polymer (PMB) that is soft to the touch.

The component (A) of the present invention is a natural mineral or a synthetic mineral containing two or more of Si, Al, Mg, and K as constituent elements, and is particularly limited if it is a mineral that is normally used in cosmetics. Not done. Examples include talc containing Si and Mg as constituent elements, sericite containing Si, Al, and K as constituent elements, and kaolin containing Si and Al as constituent elements.

The median diameter of the component (A) of the present invention is 0.5 to 2.1 μm. More preferably, it is 0.6 to 1.5 μm. If it is larger than 2.1 μm, the sphericity of the resulting spherical composite powder for cosmetics will decrease. If it is 0.5 μm or more, a spherical composite powder for cosmetics having good sphericity can be obtained.

The median diameter of the component (A) of the present invention can be determined using a general-purpose particle size distribution measuring device. For example, any of a laser diffraction method, a light scattering method, and an image analysis method may be used. Among these, in consideration of measuring the particle size range of the present invention, the laser diffraction method is preferable, and specifically, it is possible to measure the median diameter using Partica LA-950V2 (manufactured by HORIBA) or the like. can.

As the component (A) of the present invention, commercially available products can be used. For example, Nano Ace D-600 (component: talc, median diameter: 0.6 μm, manufactured by Nippon Talc Co., Ltd.), Nano Ace D-1000F (component: talc, median diameter: 1.0 μm, manufactured by Nippon Talc Co., Ltd.), etc. can be used. can. Further, in order to obtain a mineral having a desired median diameter, a mineral having a median diameter larger than 2.1 μm may be separately prepared by subjecting it to a mechanical crushing process.

What is more important as a physical property of the component (A) used in the present invention is the shear viscosity, which is an index of the dispersion state of the component (A). The sphericity of the spherical composite powder changes depending on the state of dispersion. In the present invention, the shear viscosity (shear rate 10/sec) obtained when a 40% by weight aqueous dispersion of component (A) is measured with an E-type viscometer is 100 mPa·s or more. More preferably, it is 1,000 mPa·s or more, most preferably 10,000 mPa·s or more. If the shear viscosity of the 40% by weight aqueous dispersion is less than 100 mPa·s, natural minerals or synthetic minerals may reduce the sphericity of the resulting spherical composite powder for cosmetics. A spherical composite powder for cosmetics with good sphericity can be obtained if the 40% by weight water dispersion is a natural mineral or a synthetic mineral with a shear viscosity of 100 mPa·s or more.

The shear viscosity of the 40% by weight aqueous dispersion of natural minerals or synthetic minerals constituting the spherical composite powder for cosmetics of the present invention is determined as the shear viscosity under a constant shear rate using a general-purpose E-type viscometer. can do. Specifically, the shear viscosity can be measured using Physica MCR 301 (manufactured by Anton Paar).

Considering the above physical properties, the component (A) of the present invention is more preferably talc or kaolin, and most preferably talc.

The water-soluble polysaccharide component (B) of the present invention is not particularly limited as long as it is a water-soluble polysaccharide commonly used in cosmetics. Specific examples include starch, water-soluble cellulose derivatives, and salts thereof. Examples of starches include seed starches such as rice starch, wheat starch, and corn starch, and rhizome starches such as tapioca starch and potato starch. Examples of water-soluble cellulose derivatives and salts thereof include carboxymethylcellulose and sodium carboxymethylcellulose.

The component (B) of the present invention is preferably starch. More preferred is seed starch, and most preferred is rice starch. Seed starch has a lower water swelling property than rhizome starch, and thus has a relatively low aqueous solution viscosity and good handling properties.

In the compounding step of the spherical composite powder for cosmetics of the present invention, the concentration of the aqueous dispersion of the constituent components (concentration in water that is the sum of the contents of the constituent component (A) and the constituent component (B)) is 2 to 40% by weight. It is. More preferably, it is 5 to 20% by weight. If it is more than 40% by weight, the viscosity of the aqueous dispersion containing component (A) and component (B) will increase, and the handling properties will decrease. When it is less than 2% by weight, the yield of the spherical composite powder for cosmetics decreases because the solid content concentration decreases.

The median diameter of the spherical composite powder for cosmetics obtained by the present invention is 3 to 30 μm. More preferably, it is 5 to 20 μm. If it is larger than 30 μm, a grainy feel will occur and the soft touch characteristics will be poor.

The solid content weight ratio (mineral content:water-soluble polysaccharide content) of the spherical composite powder for cosmetics obtained by the present invention is 98:2 to 80:20. More preferably, the ratio is 95:5 to 85:15. If the proportion of the water-soluble polysaccharide is greater than 20% by weight, the viscosity of the water dispersion in the compositing step will increase, resulting in poor handling. On the other hand, if it is less than 2% by weight, the binding component between minerals will decrease, resulting in a decrease in the yield of spherical composite powder for cosmetics.

The spherical composite powder for cosmetics obtained by the present invention can be used untreated, but it may also be used after being subjected to surface treatment as appropriate. The surface treatment agent is not particularly limited as long as it is a surface treatment agent that is normally used for powders for cosmetics. Specific examples of surface treatment agents include fluorine compounds, silicone compounds, ester compounds, metal soaps, waxes, oils and fats, hydrocarbons, and the like.

The spherical composite powder for cosmetics obtained by the present invention is prepared through the following aqueous dispersion preparation steps (1), (2), and composite step (3).
(1) Obtain an aqueous solution of water-soluble polysaccharide using a mechanical stirrer. At this time, in order to dissolve the water-soluble polysaccharide in water, it can be heated and dissolved as appropriate.
(2) A mineral is added to the aqueous solution of the water-soluble polysaccharide obtained in step (1), and an aqueous dispersion is obtained using a mechanical stirrer.
(3) The dispersion obtained in step (2) is subjected to a spray dryer, and the fine droplets are rapidly solidified in a high temperature field to obtain a spherical composite powder for cosmetics consisting of a mineral and a water-soluble polysaccharide.

The mechanical stirrer used in the manufacturing steps (1) and (2) of the spherical composite powder for cosmetics of the present invention is not particularly limited as long as it is a stirrer that is normally used for dispersion in liquid. Examples include a disper mixer, a homomixer, a high-pressure homogenizer, and the like.

In the manufacturing process (2) of the spherical composite powder for cosmetics of the present invention, flocculants such as aluminum sulfate (sulfate band) and polyaluminum chloride (PAC), and other inorganic salts are used to reduce the viscosity of the aqueous dispersion. may be adjusted as appropriate.

The spray dryer used in the manufacturing step (3) of the spherical composite powder for cosmetics of the present invention is not particularly limited as long as it is a spray dryer that is normally used for manufacturing granules. Spray dryers can be broadly classified into nozzle type and rotating disk type depending on the difference in spray mechanism, but spray dryers with either type of spray mechanism can be used.

In the present invention, in order to obtain a spherical composite powder for cosmetics having a preferable median diameter, among the above-mentioned spray dryers, a spray dryer equipped with a two or more fluid nozzle type or a rotating disk type spray mechanism is particularly used. It is preferable to use

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that these do not limit the present invention in any way.

(Manufacturing method) Examples 1 to 8, Comparative example 1
Step (1): Components 8 to 10 (water-soluble polysaccharides) in Table 1 below were added to component 11 (distilled water), and the aqueous solution was mixed using a homomixer (T.K. Robomix; manufactured by Primix). Prepared. Distilled water preheated to 90°C was used to dissolve components 8 and 9.
Step (2): Components 1 to 7 (minerals) in Table 1 below are added to the aqueous solution of water-soluble polysaccharide obtained in step (1), and the minerals and water-soluble polysaccharide are mixed using a homomixer under the following conditions. An aqueous dispersion of sugars was prepared. At this time, the concentration of the water dispersion was adjusted to 9.2% by weight, and the solid weight ratio of the mineral to the water-soluble polysaccharide was adjusted to 87:13.
Homo mixer rotation speed: 5000 rpm
Dispersion treatment time: 30 minutes Step (3): The aqueous dispersion obtained in Step (2) was subjected to a spray dryer (Model L-12; manufactured by Okawara Kakoki Co., Ltd.) under the following conditions, and the components 1 to 1 were A spherical composite powder for cosmetics consisting of 10 was obtained.
Spraying method: rotating disc Disc rotation speed: 25,000 rpm
Water dispersion flow rate: 160mL/min Supply air temperature: 220℃
Exhaust temperature: 105℃

(Sphericity evaluation method)
Regarding the sphericity of the spherical composite powders for cosmetics of the above examples and comparative examples, when observing the spherical composite powders for cosmetics using a scanning electron microscope at a magnification of 500 times, 100 or more of the composite powders are present in the observation field. Under these conditions, composite powders with a circularity of 0.95 or more were considered to be spherical, and their number ratio was determined according to the criteria shown below. (Circularity was calculated by determining the projected area and circumference of the composite powder from image analysis.)
<Judgment criteria>
[Percentage of number of composite powders recognized as spherical] [Judgment]
75% or more ◎
50% or more ○
Less than 50% △
Less than 25% ×

(Softness evaluation method)
A panel of five cosmetics experts in their 20s to 40s spread the spherical composite powders for cosmetics of the above Examples and Comparative Examples on their fingertips or the back of their hands and gave them a score based on the following evaluation criteria. The average score was calculated for each spherical composite powder, and the evaluation was made according to the criteria shown below.
<Evaluation criteria>
[Usability] [Rating]
Very good: 5
Good: 4
Normal: 3
Slightly poor: 2
Defective: 1
<Judgment criteria>
[Average score] [Judgment]
4.5 or more ◎
3.5 or more and less than 4.5 ○
2 or more but less than 3.5 △
Less than 2 ×

*1 Nano Ace D-1000F (manufactured by Nippon Talc Co., Ltd.)
*2 Nano Ace D-600 (manufactured by Nippon Talc Co., Ltd.)
*3 FG-15F (manufactured by Nippon Talc Co., Ltd.)
*4 SG-95 (manufactured by Nippon Talc Co., Ltd.)
*5 P-3 (manufactured by Nippon Talc Co., Ltd.)
*6 Sericite FSE (manufactured by Sanshin Koko Co., Ltd.) is atomized through a mechanical crushing process *7 ASP-170 (manufactured by BASF) is atomized through a mechanical crushing process

The shear viscosities (shear rate 10/sec) of each mineral (talc, sericite, kaolin) used in Examples 1 to 3 in Table 1 in a 40% by weight aqueous dispersion were 81,650, 340, and 2, respectively. , 920 mPa·s.

FIG. 1 shows an electron microscope image of the spherical composite powder for cosmetics obtained in Example 1. A spherical composite powder with extremely high sphericity was obtained.

As a result of producing spherical composite powders for cosmetics by changing the types of minerals with the same median diameter, good spherical composite powders were obtained in all cases, and in particular, the system using talc as the mineral had the best results. Spherical composite powders having sphericity were obtained (Examples 1 to 3).

As a result of manufacturing spherical composite powder for cosmetics using talc with different median diameters, it was found that spherical composite powder with good sphericity was obtained in the system using talc with a median diameter of 2.1 μm or less. However, in the system using talc with a median diameter of 5 μm, the sphericity decreased (Examples 1, 6 to 8, Comparative Example 1).

As a result of producing spherical composite powders for cosmetics by changing the types of water-soluble polysaccharides, good spherical composite powders were obtained in all cases, especially when rice starch and carboxymethyl cellulose Na were used as water-soluble polysaccharides. Spherical composite powders having the best sphericity among the systems were obtained (Examples 1, 4, and 5).

(Manufacturing method) Examples 9 to 14
Step (1): Component 2 in Table 2 below was added to Component 3 that had been previously heated to 90° C., and an aqueous solution was prepared using a homomixer (T.K. Robomix; manufactured by Primix Co., Ltd.).
Step (2): Add component 1 in Table 2 below to the aqueous solution of component 2 obtained in step (1), and use a homomixer to prepare an aqueous dispersion of minerals and water-soluble polysaccharides under the following conditions. did. At this time, the concentration of the water dispersion was adjusted to be 1 to 45% by weight. Further, the solid content weight ratio of mineral and water-soluble polysaccharide was adjusted to be 87:13.
Homo mixer rotation speed: 5000 rpm
Dispersion treatment time: 30 minutes Step (3): The aqueous dispersion obtained in Step (2) is subjected to a spray dryer (model MDL-050B; manufactured by Fujisaki Electric Co., Ltd.) to obtain a cosmetic composition consisting of components 1 and 2. A spherical composite powder was obtained.
Spraying method: 3 fluid nozzle PN3005
Water dispersion flow rate: 45mL/min Supply air temperature: 250℃
Exhaust temperature: 105℃

In Examples 9 to 14 shown in Table 2, spherical composite powders for cosmetics were produced by fixing the solid content weight ratio of talc and rice starch at 87:13 and varying the water dispersion concentration. In systems where the aqueous dispersion concentration of the constituent components is 2 to 40% by weight, a spherical composite powder with good sphericity and softness can be obtained. % by weight, spherical composite powders having the best sphericity and softness were obtained (Examples 9 to 12). In a system where the water dispersion concentration of the constituent components was 1% by weight, the yield of spherical composite powder was lower than in Examples 9 to 12, and the sphericity and softness were also inferior (Example 13). . In addition, in a system where the concentration of the aqueous dispersion of the constituent components was 45% by weight, the yield of spherical composite powder was high, but the results were inferior in sphericity and softness compared to Examples 9 to 12. Example 14).

(Production method) Examples 15 to 20
Step (1): Component 2 in Table 3 below was added to Component 3 that had been previously heated to 90° C., and an aqueous solution was prepared using a homomixer (T.K. Robomix; manufactured by Primix).
Step (2): Add component 1 in Table 3 below to the aqueous solution of component 2 obtained in step (1), and use a homomixer to prepare an aqueous dispersion of minerals and water-soluble polysaccharides under the following conditions. did. At this time, the solid content weight ratio of mineral and water-soluble polysaccharide was adjusted to be 1:99 to 75:25. Further, the concentration of the water dispersion was adjusted to 9.2% by weight.
Homo mixer rotation speed: 5000 rpm
Dispersion treatment time: 30 minutes Step (3): The aqueous dispersion obtained in Step (2) is subjected to a spray dryer (model MDL-050B; manufactured by Fujisaki Electric Co., Ltd.) to obtain a cosmetic composition consisting of components 1 and 2. A spherical composite powder was obtained.
Spraying method: 4 fluid nozzle SE4003
Water dispersion flow rate: 45mL/min Supply air temperature: 250℃
Exhaust temperature: 105℃

In Examples 15 to 20 of Table 3, spherical composite powders for cosmetics were produced by fixing the concentration of the aqueous dispersion of talc and rice starch at 9.2% by weight and varying the solid content weight ratio. In a system where the solid content weight ratio of the constituent components is 98:2 to 80:20, a spherical composite powder having good sphericity and softness can be obtained, and especially when the solid content weight ratio of the constituent components is 95:5, and 85:15, spherical composite powders with the best sphericity and softness were obtained (Examples 15 to 18). In systems where the solid content weight ratio of the constituent components was 99:1 and 75:25, the results were that the spherical composite powders were inferior in sphericity and softness compared to Examples 15 to 18 ( Examples 19, 20).

The present invention provides an environmentally compatible spherical composite powder for cosmetics that has tactile properties that can replace conventional synthetic polymers that have a soft feel, and a method for producing the same. By using the spherical composite powder for cosmetics of the present invention, it is possible to develop environmentally friendly cosmetic formulations.

Claims (5)

A spherical composite powder for cosmetics containing the following components (A) and (B) as constituent components.
(A) Talc with a median diameter of 0.5 to 2.1 μm, and a shear viscosity (shear rate of 10/sec) of 40% by weight water dispersion measured with an E-type viscometer of 10,000 mPa・s Items with the above physical properties
(B) Water-soluble polysaccharide without pores The spherical composite powder for cosmetics according to claim 1, wherein the component (B) is starch without pores. The spherical composite powder for cosmetics according to claim 1 or 2, wherein the component (B) is seed starch without pores. The spherical composite powder for cosmetics according to any one of claims 1 to 3, wherein the weight ratio of component (A) to component (B) is 98:2 to 80:20. A method for producing a spherical composite powder for cosmetics according to any one of claims 1 to 4, which is prepared through the following steps (1) to (3).
Step (1): Using a mechanical stirrer, an aqueous solution of water-soluble polysaccharide is obtained.
Step (2): A mineral is added to the aqueous solution of the water-soluble polysaccharide obtained in step (1), and an aqueous dispersion is obtained using a mechanical stirrer.
Step (3): The dispersion obtained in step (2) is subjected to a spray dryer, and the fine droplets are rapidly solidified in a high temperature field to obtain a spherical composite powder for cosmetics consisting of minerals and water-soluble polysaccharides. .