KR101612063B1 - A cosmetic sponge, a method for producing polyurethane elastic body and a cosmetic applicator - Google Patents

Abstract

Ethanol permeation time is in the range of 10 seconds or more and less than 400 seconds and the pore diameter of the pores having a maximum diameter of 15 to 150 占 퐉 in the range of 1.0 mm x 1.0 mm of the cross section is 150 or more and 10 or less And having a pore size of 15 to 75 μm and a pore size of 15 to 150 μm of 80% or more and a bulk density of 120 to 200 kg / m ^3. The polyurethane elastomer having a three- A cosmetic sponge that is difficult to penetrate the cosmetic material deeply into the interior and has an appropriate amount of cosmetic material to be impregnated and a wider spreading area can be obtained even when used for applying a low cosmetic material and a coagulation method using a powder of an inorganic salt having a specific particle size distribution , And a cosmetic material application port using the cosmetic sponge.

Description

A cosmetic sponge, a method for producing a polyurethane elastic body, and a cosmetic sponge, a method for producing a polyurethane elastic body and a cosmetic applicator,

The present invention relates to a cosmetic sponge, which is preferably used as a foundation puff, in particular a liquid foundation puff, a method for producing a polyurethane elastic body for forming the cosmetic sponge, and a cosmetic application using such a cosmetic sponge.

In recent years, there has been a demand for a finishing method of applying a foundation or the like to a skin as thinly and smoothly as possible, that is, finishing with "thinly adhered" and "spreading" in a cosmetic method. Therefore, a liquid type cosmetic having a low viscosity, And a liquid foundation having a reliable feel in terms of spreadability tends to be favored. Recently, there has been a tendency to have a thinner close contact, a hiding power to cover the pores, Smaller liquid foundations are beginning to be sold.

When a conventional cosmetic sponge is used as a coating agent for such a low-viscosity cosmetic, the cosmetic is absorbed deeply into the interior of the applicator, and hygienic problems such as corruption of the cosmetic remaining in the interior are liable to occur. Therefore, it is necessary to suppress the absorption to the deep inside. On the other hand, if the absorption is suppressed too much, the impregnation amount of the cosmetic material becomes smaller, and it becomes difficult to obtain a smooth spread area. Therefore, an appropriate absorption depth (amount of impregnation of cosmetic material) is desired.

As a low-viscosity cosmetic composition, various coating compositions made of polyurethane foam have been proposed. For example, Patent Document 1 discloses a puff in which a flexible foam having a skin layer is used as a core material and the core material is wrapped with a sheath material of microporous wet polyurethane. According to this puff, excessive absorption of the cosmetic material can be suppressed. However, since the manufacturing process of this puff is complicated, the manufacturing cost is significantly increased.

Patent Document 2 describes a porous body of a polyurethane resin obtained by adding a pore generating agent such as polyvinyl alcohol to a dimethylformamide solution of a polyurethane resin, coagulating in water, and then washing the pore generating agent. However, this porous body has a complicated pore structure and has an irregular shape. When used as a cosmetic sponge, there is a problem that uneven application of the cosmetic material and uneven streaks occur due to existence of a large pore.

Patent Document 3 discloses a foamed polyurethane having a continuous pore structure made of a raw material in which a silicone-based water and oil repellent agent is kneaded. When the foamed polyurethane is used as a cosmetic sponge, since the sponge skeleton is water-repellent and oil-repellent, the effect of preventing the absorption of the cosmetic material is recognized at the beginning of use, but the cosmetic material is pushed into the empty space of the continuous pore structure There is a problem that it is absorbed deep inside the sponge.

Patent Document 4 discloses a cosmetic sponge made of a polyurethane resin having two kinds of net eyes (holes) different in diameter and having a three-dimensional network structure. Since it is a three-dimensional network structure, it is described that an excellent cosmetic sponge having good touch feeling on skin, flexibility, and cosmetics is obtained (paragraph 0042). However, since the cosmetic sponge having a three-dimensional network structure as described in Patent Document 4 is repeatedly used, the cosmetic material is pushed into the hollow space of the net (hole) and is absorbed deep inside the sponge, penetrating the sponge It is not satisfactory as a cosmetic tool because it causes a problem of being attached to a finger. In addition, both the absorption depth and the spreading area are not satisfactory.

Patent Literature 5 discloses a cosmetic sponge used for applying a cosmetic material having a low viscosity such as a liquid foundation and the like. The sponge is a three-dimensional membrane structure continuous pneumatic elastomer and has an ethanol permeation time ranging from 10 seconds to less than 200 seconds, A cosmetic sponge comprising a polyurethane elastic body containing 20 or more pores having a maximum diameter of 50 占 퐉 or more and 300 占 퐉 or less within a range of 1.0 mm 占 1.0 mm in cross section is disclosed. It is described that the use of the cosmetic sponge allows the depth of absorption (amount of impregnation of the cosmetic material) to be appropriate and a wide spreading area to be obtained because the cosmetic material is hardly penetrated deep into the sponge.

Patent Document 1: JP-A-56-95012 Patent Document 2: JP-A-58-189242 Patent Document 3: JP-A-6-284923 Patent Document 4: Japanese Patent Application Laid-Open No. 2004-267277 Patent Document 5: Japanese Patent Publication No. 5148140

In recent years, however, the liquid foundation has been required to have a lower viscosity than that of the conventional liquid foundation, and has been used. Although the conventional liquid foundation is low in viscosity, it has a large degree of roughness, so that the sag length measured by a method described later is hardly recognized. However, the recent liquid foundation has a sag length of about 20 to 30 mm and a sag length of about 70 mm.

The present inventors quantitatively evaluated the impregnation amount of the cosmetic material according to the depth of absorption described later, and also quantitatively evaluated the spreading performance on the skin to the below-mentioned spreading area. As a result, the cosmetic sponge disclosed in Patent Document 5 exhibits the above-mentioned excellent effect, but when it is used in a liquid foundation having a lower viscosity and lower squeezability which is recently demanded, the absorption depth and spreading area are sufficiently satisfactory It is confirmed that it can not be said. For example, in the case of a cosmetic having a low viscosity and low roughening property, the cosmetic filled in the pores of the sponge easily penetrates deeply into the inside of the sponge, resulting in insufficient cosmetic effect due to insufficient amount Lt; / RTI >

The present invention solves the problems of the prior art as described above, so that even when the present invention is applied to a cosmetic material having a low rigidity and low viscosity, such as a recent liquid foundation, it is difficult for the cosmetic material to penetrate deeply into the interior of the sponge, Absorption depth) of the cosmetic sponge is suitable, a wide spread area is obtained, and a recent request is satisfied sufficiently.

It is still another object of the present invention to provide a method of producing a polyurethane elastic body constituting a cosmetic sponge that can sufficiently satisfy recent demands and which has an absorption depth and a spreading area, and a cosmetic applicator using the cosmetic sponge.

As a result of intensive research, the inventors of the present invention have found that a polyurethane continuous pneumatic elastomer (polyurethane foam) having a three-dimensional membrane structure has an ethanol permeation time within a predetermined range and pores having a pore diameter (maximum diameter) Even when a polyurethane elastic body containing a large amount and a density within a predetermined range is used for a liquid foundation having low viscosity and low viscosity, it is possible to provide a cosmetic sponge capable of obtaining an absorption depth and a spread area sufficiently satisfying recent demands And completed the present invention.

That is,

As a three-dimensional membrane structure continuous pore elastomer,

Ethanol permeation time is in the range of 10 seconds to less than 400 seconds,

A pore having a maximum diameter of not less than 15 μm and not more than 150 μm and a maximum diameter of not more than 10 μm and a maximum diameter of not less than 15 μm and not more than 75 μm the number of not less than 80% of the maximum diameter of 15μm or more number of pores of 150μm or less, and a make-up sponge (claim 1), characterized in that the apparent density consisting of 120 ~ 200kg / m ³ polyurethane elastomer.

Further, the present invention provides a cosmetic sponge (claim 2) according to claim 1, wherein the pores of the polyurethane elastic body have a substantially circular or elliptical cross-sectional shape.

In addition,

A step of kneading a blend containing a water-solidifying polyurethane, a solvent, a powder of a water-soluble inorganic salt and a surfactant having an HLB of less than 8.6 as a main component to obtain a kneaded product,

A step of defoaming the kneaded product to obtain a defoaming kneaded product,

A step of molding the defoaming kneaded product to obtain a molded product,

A step of putting the molded product in water or an aqueous solution and then solidifying to form a solidified product,

Eluting the inorganic salt from the solidified product in water to remove the solid salt, and

And a step of drying after the elution is removed,

Wherein the particle size of the water-soluble inorganic salt is 10% by mass or less, the particle group of 15 占 퐉 or more and less than 75 占 퐉 is 35 to 85% by mass, the particle size of 75 占 퐉 or more and 150 占 퐉 or less is 50% (Particle size) of 10% by mass or less. The present invention also provides a method for producing a polyurethane elastic body (claim 3).

Further, the present invention provides a cosmetic application device (claim 4), characterized by using the cosmetic sponge according to claim 1 or claim 2.

The cosmetic sponge of the present invention is a three-dimensional film structure having a pore controlled in diameter and number, a resin film and an opening film between adjacent pores, and a ratio of the area of the resin film to the area of the opening within a suitable range ,

Permeability and liquid permeability can be obtained, the impregnation amount of the cosmetic material (adhesion amount to the cosmetic sponge) having a low plasticity and a low viscosity is suitable,

Even a cosmetic having a low viscosity is difficult to penetrate deeply into the inside of the sponge, and there is no drawback that the blast cosmetics tend to penetrate through the net (hole). Further, when the cosmetic sponge of the present invention is used as a coating tool, a smooth spread area can be obtained. In addition, it does not have a strong rebound resilience, and has excellent properties with a feeling of soft and moist skin feeling. That is, according to the cosmetic sponge of the present invention, even when used as a liquid foundation puff or the like having low squeezability or low viscosity as required in recent years, the absorption depth and spread area sufficiently satisfying recent demands can be obtained .

According to the production method of the present invention, a continuous pore elastomer (polyurethane elastomer) of a polyurethane resin having pores controlled in diameter and number can be obtained as a three-dimensional membrane structure without requiring a complicated manufacturing process, The elastic body is the above-described cosmetic sponge of the present invention having excellent properties as a cosmetic material having low sagging and low viscosity.

The cosmetic sponge of the present invention is preferably used as a cosmetic coating composition such as a foundation puff or a tip for an eye shadow, and is particularly preferably used as a cosmetic composition having a low viscosity, for example, as a coating liquid for a liquid foundation of low viscosity.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a particle size distribution diagram of the mallow salt used in Examples and Comparative Examples. FIG.
2 is a scanning electron micrograph of a section of the cosmetic sponge obtained in Example 1. Fig.
3 is a scanning electron micrograph of a section of the cosmetic sponge obtained in Example 2. Fig.
4 is a scanning electron micrograph of a section of the cosmetic sponge obtained in Comparative Example 1. Fig.
5 is a scanning electron micrograph of a section of the cosmetic sponge obtained in Comparative Example 2. Fig.
6 is a scanning electron micrograph of a section of the cosmetic sponge obtained in Comparative Example 3. Fig.
7 is a view showing a mechanism for measuring an ethanol permeation time.
8 is a schematic view for explaining the pores of the continuous pore elastomer.

Hereinafter, embodiments for carrying out the present invention will be described more specifically. However, the scope of the present invention is not limited to this embodiment, but various modifications can be made within the scope of the invention.

[Composition of cosmetic sponge]

The continuous pneumatic elastomer constituting the cosmetic sponge of the present invention is an elastic body of polyurethane.

The polyurethane is obtained by reacting a polyisocyanate compound with a polyol component comprising a high molecular weight polyol and a chain extender. Examples of the high molecular weight polyol include polyether polyols such as polypropylene glycol, polytetramethylene glycol and polymer polyol, polyester polyols such as adipate polyol and polycaprolactone polyol, polycarbonate polyol and polyolefin polyol. The molecular weight is 500 to 10000. Examples of the chain extender include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol and 1,3-propanediol. Examples of the polyisocyanate compound include aromatic isocyanates such as methylene diphenyl diisocyanate, tolylene diisocyanate, xylene diisocyanate, naphthylene 1,5-diisocyanate and tetramethylene xylylene diisocyanate, isophorone diisocyanate, dicyclohexyl methane diisocyanate And alicyclic isocyanates such as hexamethylene diisocyanate, dimeric acid diisocyanate and norbornene diisocyanate.

The cosmetic sponge of the present invention is characterized by being made of a continuous pore-elastic body of a three-dimensional membrane structure. The three-dimensional membrane structure refers to a structure in which the pores constituting the porous body are uniformly distributed in the three-dimensional direction and are continuous with each other, and a part of the pores is the membrane. That is, it means that the contact portion (the surface of the pores, the boundary with the adjacent pores) between the pores is formed by the holes (openings) connecting the film and pores of the resin.

The three-dimensional membrane structure is different from the three-dimensional network structure in which the pores constituting the porous body are continuous to each other in the three-dimensional direction, and the film is hardly observed at the contact portion between the pores of the porous body. In addition, in the closed-celled polyurethane foam made of completely independent bubbles, the surface of the bubble (pore) is covered with the film of the polyurethane resin and has no opening portion. The three-dimensional membrane structure differs from the fully closed cell polyurethane foam in that it has openings, although the surface of the pores is covered with a film of polyurethane resin.

The inventors of the present invention have found that a polyurethane foam (a closed-cell polyurethane foam) having a sponge structure in which adjacent pores are separated by membranes and the pores are independent has strong rebound resilience, and a feeling of soft and moist skin feeling is obtained On the other hand, in the case of a polyurethane cosmetic sponge having a three-dimensional network structure as described in Patent Document 4, there is a problem in that the amount of impregnation (caking) It is noted that there is no film, so that the cosmetic material is easy to penetrate through the net, and the spreadability on the skin is small. A three-dimensional membrane structure in which adjacent pores are divided into membranes and the membranes have openings and a part of the pores are continuous and the area ratio of the membranes and the openings is in an appropriate range, The present inventors have found that a cosmetic sponge having an adequate amount of the cosmetic material to be impregnated and a high spreading property on the skin can be obtained because the repellent elasticity is not strong and the skin feeling is flexible and moist. It has been found that a cosmetic sponge which can be suitably applied to a cosmetic having a low friability and a low viscosity such as a liquid foundation can be obtained by having the following characteristics.

The cosmetic sponge of the present invention is characterized in that the ethanol permeation time ranges from 10 seconds to less than 400 seconds. The ethanol permeation time varies depending on the average pore diameter, the distribution of the pore diameter, and the area ratio of the resin film occupying the contact portion between the pores, that is, the ratio between the membrane and the opening portion between the pores.

As described above, the three-dimensional membrane structure and the three-dimensional network structure are distinguished according to the size ratio of the membrane portion and the opening portion occupying the contact portion between the pores of the porous body. In the three-dimensional network structure, the ethanol permeation time is short, As the membrane structure becomes larger and the area ratio of the membrane becomes larger, the ethanol permeation time becomes longer. The ethanol permeation time of 10 seconds or more is a three-dimensional membrane structure, which indicates that the area ratio of the membrane is not less than a predetermined value. The present inventors have found that the area ratio of the membrane portion and the opening portion is closely related to the ethanol permeation time. It is difficult to actually measure the area of the membrane part and the opening part by using a microscope photograph or the like and it is difficult to directly determine an appropriate range of the area ratio according to the numerical value. However, based on the measurement value of the ethanol permeation time, A sponge having an appropriate range of the ratio is obtained.

The cosmetic sponge of the three-dimensional membrane structure is formed by the pores and has a membrane between the pores, so even cosmetics having low viscosity or viscosity can not penetrate deeply into the interior of the sponge. At the same time, since the pores of the three-dimensional film structure also have openings, a proper amount of the cosmetic material is easily impregnated and a wide spread area is easily obtained. Since the area ratio between the film portion and the opening portion is within a suitable range, an excellent cosmetic sponge having an appropriate depth of absorption and a wide spreading area can be obtained. If the ethanol permeation time is shorter than 10 seconds, the sponge structure becomes closer to the three-dimensional network structure and the spreading area becomes smaller, which is not preferable. The penetration of the cosmetic material is too fast to be absorbed deep inside the sponge, and in particular, in the case of the rubbing of a liquid foundation such as a liquid foundation and a low viscosity cosmetic material, the cosmetic material tends to be attached to the finger through the sponge.

On the other hand, if the ethanol permeation time is longer than 400 seconds, the pores can be seen in a membrane structure with too small pores, and the depth of absorption of the cosmetic material becomes small. Further, the impregnation amount of the cosmetic material becomes insufficient, and the spreadability of the cosmetic material becomes insufficient.

The ethanol permeation time in the present invention is a time required for a certain volume of ethanol to permeate a polyurethane elastic body (sponge: test piece) having a predetermined length and area, specifically, measured as follows. In other words,

"A glass tube having a length of 300 mm and an inner diameter of 17.4 mm was vertically erected and a stopper having a hole having a diameter of 6.8 mm was formed on the bottom thereof and the hole was cut into a polyurethane elastic body (sponge: test piece) sliced at a thickness of 4.0 mm The polyethylene film is pressed from the outside of the elastic body and fingers are pushed in. The position of 30 mm in height from the bottom of the glass tube is set as the lower scale and the position of 130 mm is set as the upper scale. The polyethylene film is separated and the ethyl alcohol is flowed down. The time from the top of the ethyl alcohol until passing through the upper scale until passing through the lower scale is called the ethanol permeation time. ℃. "

The ethanol permeation time is preferably 20 seconds or more and less than 350 seconds.

The polyurethane continuous pneumatic elastomer constituting the cosmetic sponge of the present invention has 150 or more pores having a maximum diameter of not less than 15 μm and not more than 150 μm and a pore having a maximum diameter of more than 150 μm in a range of 1.0 mm × 1.0 mm And the number of pores having a maximum diameter of 15 μm or more and 75 μm or less is 80% or more of the number of pores having a maximum diameter of 15 μm or more and 150 μm or less.

By making the number of pores fall within the above range, a cosmetic sponge having an excellent spreading area and an absorption depth can be obtained. When the number of pores having a maximum diameter of 15 占 퐉 or more and 150 占 퐉 or less is less than 150 in the range of 1.0 mm 占 1.0 mm of the cross section, the spreading area becomes small and is not suitable as a cosmetic sponge. Preferably, the number of pores having a maximum diameter of 15 占 퐉 or more and 150 占 퐉 or less is 200 or more in the range of 1.0 mm 占 1.0 mm of the cross section.

When the number of pores having a maximum diameter of 15 μm or more and 75 μm or less is less than 80% of the number of pores having a maximum diameter of 15 μm or more and 150 μm or less, that is, when pores having a diameter of 75 μm or more and 150 μm or less are large, the depth of absorption is too large and the spreading area is small. It is not suitable as a sponge for sponges. Further, even when the number of pores having a maximum diameter exceeding 150 占 퐉 exceeds 10, the absorption depth is too large and the spreading area becomes small, so that it is not suitable as a cosmetic sponge.

The number of pores is a value measured by an electron micrograph of a cross section of the polyurethane continuous pore elastic body. That is, a microphotograph was taken in the range of 1.0 mm x 1.0 mm in cross section of the polyurethane elastic body, and pores having a pore diameter (maximum diameter) in the range of 15 m to 75 m in the microscope photograph, pores larger than 75 m and smaller than 150 m, Perform pore counting in excess of 150μm. The number of pores in and out of the measurement range is calculated as 0.5.

Here, the pore diameter refers to the maximum distance among the distances connecting the two points on the outer periphery of the pores observed on the microscope photograph. 8 is a schematic view for explaining the pores of the continuous pneumatic elastomer and is a schematic view of a microscope photograph of the cut surface. The maximum distance (L in Fig. 8) among the distances connecting the two points A and B on the pore outer periphery on Fig. Diameter.

Further, the cross-sectional shape of the pores often has a substantially circular or elliptical shape (Claim 2). When the pores have substantially different shapes from those of the substantially circular or elliptical shape, the shape thereof is divided into a substantially circular shape or an elliptic shape, and the number of the substantially circular or elliptic shapes is determined as the number of pores. For example, having a protrusion at the center portion is divided into two or more pores having a substantially circular or elliptical shape to count the number of pores. In the example of Fig. 8, the hole a is classified into three holes a1, a2 and a3, and the hole b is classified into four holes b1, b2, b3 and b4. An optical microscope or an electron microscope is used as a microscope for photographing a microscope.

The polyurethane continuous pneumatic elastomer constituting the cosmetic sponge of the present invention has an apparent density of 120 to 200 kg / m ³ . And optionally a maximum diameter of 15μm pores of more than 150μm or less satisfy the above condition, when the pores of diameter less than 15μm, there are too many things apparent density is more than 200kg / m ^3. When the apparent density is less than 120 kg / m ^3, the mechanical strength of the obtained sponge is extremely lowered, and it tends to be difficult to withstand use. When the apparent density exceeds 200 kg / m ³ , the sponge hardness becomes too hard, which is unsuitable for cosmetics.

The cosmetic sponge of the present invention having the above characteristics can be produced by the method for producing the polyurethane elastomer of the present invention. The manufacturing method will be described as follows.

In the method for producing a polyurethane elastic body of the present invention, a step of kneading a mixture containing a water-solidifying polyurethane, a solvent, a powder of a water-soluble inorganic salt and a surfactant having an HLB of less than 8.6 as a main component to obtain a kneaded product is performed.

In water or in an aqueous solution, the solvent is replaced with water to precipitate the polyurethane, which is referred to as water coagulation, and the coagulated polyurethane refers to a polyurethane that can solidify. The elastic body of the polyurethane constituting the cosmetic sponge of the present invention is preferably formed of a water-solidifying polyurethane. The desired flexibility of the urethane foam is likely to be obtained by water-solidification.

The coagulation does not necessarily have to be carried out in water, but may be carried out in an aqueous solution. For example, by coagulating in an aqueous solution containing an inorganic salt or a solvent, the rate of coagulation of the polyurethane is moderated to prevent the generation of large voids (voids far exceeding the particle size of the pore generating agent).

Examples of the coagulating polyurethane include those obtained by polymerizing a polyol component comprising a high molecular weight polyol and a chain extender with a polyisocyanate compound in a solvent. In addition, the polyurethane polymerized without a solvent may be dissolved in a solvent. As the water-solidifying polyurethane used in the production method of the present invention, a solution of a solid content of 30 ± 5 mass% and a viscosity of 30 to 300 Pa · s (value measured by a No. 6 rotor of a BH type viscometer at 25 ° C.) Is preferably used. When a coagulating polyurethane having a viscosity of less than 30 Pa · s is used, the strength of the resulting cosmetic sponge may be insufficient. When the viscosity exceeds 300 Pa · s, the kneaded material is difficult to flow, which may take a long time.

In addition, the feel of soft and repulsive elasticity is not strong, and the feeling of moist skin is generally expressed as hardness. The hardness suitable for the cosmetic sponge is within the range of 30 ° to 70 ° as measured using an Asuka F type hardness meter. When the hardness is too low, for example, there arises a problem that the step of performing the polishing process on the peripheral portion in the production of the cosmetic puff becomes difficult because it is too soft. On the other hand, when the hardness is high, there is a problem that the skin touches the skin strongly, resulting in deterioration of the feel.

The hardness of the polyurethane continuous pneumatic elastomer (cosmetic sponge) can be freely controlled by selecting the combination of the polyol component and the polyisocyanate compound used in the synthesis of the polyurethane and the blending ratio. Also in the production method of the present invention, a cosmetic sponge within the preferable range can be obtained by appropriately selecting a polyol component and a polyisocyanate compound.

The solvent used in the production method of the present invention means a good solvent of polyurethane, and usually includes dimethylformamide, dimethylsulfoxide, dioxane, tetrahydrofuran, methylpyrrolidone, N-methylpyrrolidone And organic solvents and combinations thereof. Among them, dimethylformamide is preferable in view of the fact that it can be easily eluted with water in a subsequent step, the solvent odor as a working environment, flammability and the like. The solvent may also be used to adjust the fluidity of the kneaded product.

The amount of the solvent is preferably, for example, in the range of 2 to 50 parts by mass based on 100 parts by mass of the polyurethane solution (water-solidifying polyurethane) having a solid content of 30% by mass. When the addition amount is less than 2 parts by mass, the kneaded product is difficult to flow, so that molding may take a long time. When the addition amount exceeds 50 parts by mass, the strength of the obtained cosmetic sponge may be insufficient.

In the production process of the present invention, the granules of the water-soluble inorganic salt are kneaded with the water-solidifying polyurethane and the solvent to obtain a kneaded product. As the powder of the water-soluble inorganic salt, chlorides such as sodium and potassium, sulfate and the like may be used alone or in admixture of two or more.

In the production method of the present invention, the water-soluble inorganic salt particles to be kneaded with the water-coagulable polyurethane and the solvent are 10% by mass or less of particles having a particle size of less than 15 占 퐉, 35 to 85% by mass of particles having a particle size of 15 占 퐉 or more and less than 75 占 퐉, 50% by mass or less of particles in the range of 75 占 퐉 or more and 150 占 퐉 or less, and 10% by mass or less of particles in the particle diameter exceeding 150 占 퐉. By using particles having the above-mentioned particle size distribution as the inorganic particles, it is possible to obtain a polyurethane elastomer having a pore size of 150 mm or more and a maximum diameter of 150 mu m or more within a range of 1.0 mm x 1.0 mm, It is possible to obtain a polyurethane elastic body having not more than 10 pores having a diameter of not less than 150 μm and not more than 80% of the number of pores having a maximum diameter of not less than 15 μm and not more than 75 μm and a maximum diameter of not less than 15 μm and not more than 150 μm.

The granules of the water-soluble inorganic salt are added in an amount of 100 to 2000 parts by mass, preferably 500 to 1500 parts by mass, based on 100 parts by mass (converted to solid content) of the polyurethane. A polyurethane elastomer having an apparent density of 120 to 200 kg / m ³ can be obtained by blending the powder of the inorganic salt having the above-mentioned particle size distribution with the added amount of the above range. When the addition amount is 100 parts by mass or less, the inorganic salt is dispersed without being connected in the formulations, resulting in a nonuniform sponge skeleton structure. On the other hand, if the amount exceeds 2,000 parts by mass, the mechanical strength of the obtained sponge is extremely lowered, and the sponge is liable to be unable to withstand use.

The production method of the present invention is characterized in that, in the step of kneading a mixture containing water-solidifying polyurethane, a solvent and a powdery material of a water-soluble inorganic salt as a main component to obtain a kneaded product, a surfactant having an HLB of less than 8.6 as a three- . By coexisting a surfactant having an HLB of less than 8.6, the resulting polyurethane elastomer tends to have a three-dimensional film structure.

When a surfactant having an HLB value of 8.6 or more is used as a surfactant, or when a surfactant having an HLB of less than 8.6 is not used, the cosmetic sponge tends to have a three-dimensional network structure. Preferably, a surfactant having an HLB of 8.2 or less is used, and in this case, the three-dimensional film structure is more likely to be formed. Here, the HLB value is a known index indicating the balance between the hydrophilicity and the hydrophobicity of the surfactant, and is described in Ochimichinori et al., Chemical Dictionary published by Tokyo Kagaku Kogyo Inc., pp. 178, and the like. For example, when the surfactant is a fatty acid ester, it is calculated according to the following formula.

  HLB = 20 x {1- (SV / NV)}

Where SV is the saponification value of the ester and NV is the neutralization value of the fatty acid.

The addition amount of the surfactant having an HLB value in the range of less than 8.6 is preferably in the range of 5 to 45 parts by mass with respect to 100 parts by mass (converted to solid content) of the polyurethane. When the amount is less than 5 parts by mass, the cosmetic sponge tends to have a three-dimensional network structure. Even when the addition amount exceeds 45 parts by mass, the polyurethane elastomer has a three-dimensional film structure, which is not preferable because the amount of addition is too large, so that stickiness is felt when touched with a finger.

Surfactants with an HLB value in the range of less than 8.6

Examples of sorbitan fatty acid esters include sorbitan sesquioleate (3.7), sorbitan monooleate (4.3), sorbitan monostearate (4.7) and the like,

As the urea glyceride ethylene oxide adduct, for example, NK-3 (6.6) manufactured by Asahi Denka Kogyo K.K.,

Examples of the polyglycerin fatty acid esters include diglycerin monolaurate ester (8.5), diglycerin monopalmitate (7.3), diglycerin monostearate (6.9), tetraglycerin tristearate (4.7), tetraglycerin penta (4.3), decaglycerin hepta stearic acid ester (4.3), decaglycerin octa stearic acid ester (4.3), decaglycerin hepta stearic acid ester (4.5), hexaglycerin tristearic acid ester , Decaglycerin decahexanoic acid ester (3.4), decaglycerin heptabehenic acid ester (4.2), decaglycerine decabehenic acid ester (2.3), diglycerin monooleate (6.9), diglycerin sesquioleate ester (4.9) , Diglycerin dioleate (3.7), diglycerin tetraoleate (5.6), decaglycerin pentaeryhenate (6.4), decaglycerin pentaeryhenate (5.6), decaglycerin tetraoleate (7.6), decaglycerin pentaerythritol ester Decaglycerin heptaoleic acid ester (4.9), decaglycerin octaoleic acid ester (4.3), decaglycerin decaoleic acid ester (3.4), decaglycerinonaneric acid ester (3.2), diglycerin monoisopalmitic acid ester (7.3) , Diglycerin triisostearate (2.3), diglycerin tetraisostearate (1.5), triglycerine diisostearate (5.3), and the like, and the like.

As the polyethylene glycol oleate, for example, OEG-102 (7.9) manufactured by Asahi Denka Kogyo Co.,

As special phenol ethoxylate, for example, PC-1 (4.2) manufactured by Asahi Denka Kogyo Co., Ltd. and the like can be mentioned. The values in parentheses indicate the HLB value.

Other components may be added to the formulation as the main component of the coagulable polyurethane, the solvent, the powder of the water-soluble inorganic salt, and the surfactant of less than HLB 8.6. For example, a water-soluble polymer may be added to make the kneaded product more fluid. The water-soluble polymer is preferably dissolved in a solvent, and examples thereof include synthetic products such as polyvinyl alcohol, semi-synthetic products such as methylcellulose and carboxymethylcellulose, and natural products such as polymer polysaccharides. In addition to the above surfactant having an HLB of 8.6 or less, a surfactant having an HLB of 8.6 or more may also be added within the range not impairing the object of the invention in order to hydrophilize the resulting polyurethane elastomer. In addition, a functional material such as a coloring agent, an antioxidant, a mold inhibitor, an antibacterial agent, a material exhibiting various lubrication functions, a flame retardant, and a conductive material such as carbon black may be added.

A kneader, an auger kneader, a Banbury mixer, and a screw extruder are used for kneading the above blend.

In the production process of the present invention, after the kneaded product is obtained as described above, the obtained kneaded product is defoamed and molded. The purpose of the degassing is to remove air bubbles in the composition, and the degassing and shaping method is not particularly limited. More specifically, for example, there is a method of performing vacuum degassing using a vent type extruder, A method of connecting a forming die (T die) to give a shape to a desired shape is preferably exemplified.

After molding, the molded article is put into water or an aqueous solution to replace the solvent with water to precipitate the polyurethane, followed by water (solidification). There is no particular limitation on the shape until the molded body is put in. For example, in the molding step, a punching metal made of stainless steel 304 or the like is used to form a box having an open top face, and the kneaded material is extruded and filled to perform molding , And then introducing it into water or an aqueous solution.

After the water is solidified, the inorganic salt soluble in water is removed by water extraction. As a specific method for this purpose, for example, a molded product of a kneaded product in a container is left in hot water to extract most of the inorganic salt soluble in water, and then the molded product is introduced into a general washing machine, Minute, and water exchange is performed several times during the washing.

The thus obtained molded article is dried. In order to prevent deterioration of the polyurethane resin due to heat, drying is preferably performed at 110 ° C or lower. Drying can be carried out using a box-type dryer, a tambour-type dryer or the like. In this way, a polyurethane elastic body having a three-dimensional film structure can be obtained.

When a low-viscosity cosmetic material such as a liquid foundation is adhered to the surface of the cosmetic sponge obtained from the polyurethane elastomer of the present invention thus obtained, the cosmetic material has a low viscosity and is accumulated in the pores in an instant. In the case where the sponge is a continuous pore elastic body and the membrane is not formed between the pores (three-dimensional network structure), since the foundation is easily transferred to the adjacent pores, it is continuously absorbed into the inside of the sponge, However, in the case of a cosmetic sponge having a three-dimensional membrane structure, since there is a film between adjacent pores, the foundation is accumulated near the surface of the sponge, And the problem is suppressed because the transition to the surface layer of the sponge is obstructed. The cosmetic sponge of the present invention is more effective than the conventional cosmetic sponge and exhibits its effect sufficiently even in cosmetics and liquid foundations having lower viscosity and less plasticity. Further, the cosmetic sponge produced by water coagulation satisfies the flexibility as a cosmetic sponge.

The cosmetic sponge of the present invention does not have a strong rebound resilience, has a feeling of soft, moist skin feeling, has no drawback that the cosmetic material penetrates, has a suitable amount of cosmetic material impregnated (absorption depth), and has a wide spread area . Therefore, this cosmetic sponge is used for a cosmetic application such as foundation puffs and eye syringe tips. The present invention also provides a cosmetic material coating composition characterized by using not only the above-described cosmetic sponge, and the method for producing the polyurethane elastomer used for forming the same but also the cosmetic sponge (polyurethane elastomer) (claim 4) .

[Example]

Assessment Methods

[Micrograph: number of pores having a maximum diameter of 15 μm or more and 150 μm or less]

The cosmetic sponge was cut, and a microscope photograph of the cut surface was taken using a scanning electron microscope JSM 5500LV manufactured by JEOL Ltd. The number of pores having a maximum diameter of 15 μm or more and 75 μm or less and the number of pores having a maximum diameter of 75 μm or more and 150 μm or less were measured on a microscope photograph of 50 × to 400 ×.

[Apparent Density] The density was measured in accordance with JIS K 7222.

[Tensile strength and elongation] The tensile strength and elongation were measured in accordance with JIS K 6400-5.

[Hardness] The hardness was measured using an Asuka rubber hardness meter F type of a polymeric agent.

[Viscosity of sieves (sieving viscosity): sag length]

Using a syringe, the foundation is placed on a horizontal transparent film (KOKUYO reproduced OHP film VF-1300N) of 0.11 to 0.13 g, and the film is placed vertically. The foundation with low volumetric viscosity and low viscosity starts to sag down and hangs until the sagging is dry and hard (about 24 hours, 22 ~ 28 ℃). Thereafter, the length of the sagging is measured by measuring the length of the sagging, which is referred to as a sag length.

[Absorption depth]

A foundation with a sag length of 23 mm was used. On the horizontal transparent film (KOKUYO regeneration overhead transparency VF-1300N), the same film cut out in a square of 10 mm in width and 10 mm is bonded with double-sided tape. The above foundation was put into a cut part (10 x 10 x 0.2 mm) using a syringe and the foundation was scratched with a thin metal plate (straight line: KOKUYO PRO TZ-RS15) to flatten the surface, Swab the surplus foundation with a cotton swab. Thereafter, a square sample (sponge) having a thickness of 8 mm and a length of 2 cm is placed thereon. Put weight (weight) of 500g on it and remove it within 1 second. After this operation is repeated 10 times, the sponge is cut vertically with sharp scissors, and the depth of the cosmetic material absorbed into the sponge is measured by a straight line. The measurement temperature is 22 ~ 28 ℃.

[Spreading area]

A rectangular SUS 304 plate having a thickness of 0.75 mm and a length of 2 cm is bonded to a square sample (sponge) having a thickness of 8 mm and a length of 2 cm by double-sided tape. Thereafter, a foundation (sponge) is attached to the sample (sponge) in the same manner as in the case of the measurement of the absorption depth. The sample after foundation was placed on a piece of paper (Kokuyo-14N B4, 1 mm grid (240 x 340)), the fingers were placed on the SUS surface and the cosmetic was spread evenly so that the sponge thickness was about 4 mm, (Cm < ² >) was measured. The measurement temperature is 22 ~ 28 ℃.

[Ethanol permeation time]

A glass tube having a length of 300 mm and an inside diameter of 17.4 mm is vertically erected, and a stopper having a hole having a diameter of 6.8 mm is formed on the bottom thereof. Fig. 7 shows a cross-sectional view of the glass tube covered with a stopper. This hole is closed with a fixture (shown in a sectional view and a plan view in Fig. 7 (b)) with an elastic body (sponge: test piece) sliced to a thickness of 4.0 mm as shown in Fig. 7 (b). Fig. 7 (c) shows the state after the hole is closed with the elastic body. Further, the polyethylene film is pressed from the outside of the elastic body, and is pressed by a finger. A position at a height of 30 mm from the bottom of the glass tube is defined as a lower graduation, and a position of 130 mm is defined as an upper graduation. After injecting ethylene alcohol up to 200 mm in height, the polyethylene film is separated and ethyl alcohol is dropped therefrom. The time from the top of the ethyl alcohol through the top scale to the bottom of the scale is called the 'ethanol permeation time'. The measurement temperature is 22 ~ 28 ℃.

Example 1

The raw materials used for producing the polyurethane elastic body (cosmetic sponge) are shown below.

· F-151 (Polyester polyurethane manufactured by FUSHIMI Pharmaceutical Co., Ltd., solid content: 30%)

50 parts by mass

· T-191 (polyether polyurethane manufactured by Fushimi Pharmaceutical Co., Ltd., solid content: 30%)

50 parts by mass

15 parts by mass of dimethylformamide

Solan 30 (sorbitan sesquioleate HLB value of Daiichi Kogyo Seiyaku Co., Ltd., 3.7)

4 parts by mass

· Neutral anhydrous mangoste B

400 parts by mass

In addition, the neutral anhydride B has the particle size distribution shown in Table 1 and Fig. The particle size distribution of the neutral anhydrous manganese used in the other Examples and Comparative Examples is also shown in Table 1 and Fig. In the following description, a neutral anhydrous anion is abbreviated and indicated as an anion.

Each of the raw materials (about 20 kg in total amount) was put into a kneader having a capacity of 30 L adjusted at 40 캜 and kneaded at a rotation speed of 15 rpm for 30 minutes. The mixture was extruded at a set temperature of 40 DEG C under reduced pressure defoaming from a vent type extruder equipped with a T die having an internal diameter of 300 x 20 mm. The extruded molding was filled in a box-shaped container having an upper surface of 300 mm in length and 600 mm in height and 30 mm in height, made of SUS 304 punching metal. This was immersed in water at 50 ° C for 24 hours to replace the dimethylformamide with water to effect so-called water coagulation. After the solidification was completed and most of the inorganic salt (gum) was extracted, the molded product was separated from the container, placed in a domestic washing machine, and washed with water at 50 ° C. Thereafter, it was dried at 100 DEG C for 8 hours using a box-type dryer.

The thus obtained sponge was removed with a slicing machine to obtain a cosmetic sponge having a thickness of 8 mm and a thickness of 4 mm. (Maximum diameter) of not less than 15 占 퐉 and not more than 75 占 퐉, the number of pores larger than 75 占 퐉 and not more than 150 占 퐉 , And pore number exceeding 150 m were measured. The apparent density, tensile strength and elongation, hardness, depth of absorption, spreading area and ethanol permeation time were measured by the above evaluation method. A scanning electron microscope photograph is shown in FIG. 2, and the results of each measurement are shown in Table 2. As shown in Fig. 2, the obtained cosmetic sponge has a three-dimensional film structure.

Example 2

A polyurethane elastomer was obtained in the same manner as in Example 1 except that the cement C (available from Fushimi Chemical Co., Ltd.) having the particle size distribution shown in Table 1 and Fig. 1 was used instead of cement B, and the pore diameter (Maximum diameter) of 15 μm or more and 75 μm or less, the number of pores larger than 75 μm and not more than 150 μm, and the number of pores larger than 150 μm were measured and the apparent density, tensile strength and elongation, hardness, depth of absorption, spreading area, Were measured. A scanning electron micrograph is shown in FIG. 3, and the results of each measurement are shown in Table 2. As shown in Fig. 3, the obtained cosmetic sponge has a three-dimensional film structure.

Comparative Example 1

A polyurethane elastomer was obtained in the same manner as in Example 1 except that the starch A (sold by Fushimi Chemical Co., Ltd.) having the particle size distribution shown in Table 1 and Fig. 1 was used instead of the starch B, (Maximum diameter) of 15 μm or more and 75 μm or less, the number of pores larger than 75 μm and not more than 150 μm, and the number of pores larger than 150 μm were measured and the apparent density, tensile strength and elongation, hardness, depth of absorption, spreading area, Were measured. A scanning electron micrograph is shown in FIG. 4, and the results of each measurement are shown in Table 2.

sulphate of soda Particle size distribution range (μm) 0 to 15 15 ~ 75 75 to 150 15 to 150 150 < A 3.14 26.34 17.05 46.53 53.47 B 5.22 44.88 43.08 87.96 6.82 C 9.14 83.34 6.91 99.39 0.61 R-15 79.74 20.26 0 0 0

 (unit %)

Comparative Example 2

[0154] Rancho C (commercially available from Fushimi Chemical Co., Ltd.) was pulverized and classified by the following crushing classifier to prepare a rope called R-15 having the particle size distribution shown in Table 1 and Fig. The particle size distribution of R-15 was measured using the following particle size distribution measuring apparatus. The other examples used in the Examples and Comparative Examples are also the same.

· Grinding classifier: ACM Parpelizer H type, manufactured by Hosokawa Micron Corporation, type ACM-30H

· Particle size distribution measuring instrument: Microtrac HRA manufactured by Honewell, type 9320-x100

A polyurethane elastomer was obtained in the same manner as in Example 1 except that the above-mentioned gum R-15 was used in place of the gum B. However, the sponge after drying exhibited clear shrinkage and had a length of 69% and an F-type hardness of 100, which was the upper limit value, as compared with the normally obtained dimensions, and thus it could not be used as a cosmetic sponge.

Therefore, the amount of R-15 added was reduced to half the amount described in the Examples, and a polyurethane elastic body close to a normal size was obtained in the same manner as in Example 1 again. However, as shown in Table 2, the hardness was so large that it was difficult to use it as a cosmetic sponge.

The number of pores having a pore diameter in the range of 15 μm or more and 75 μm or less, the number of pores larger than 75 μm and less than 150 μm, and the number of pores larger than 150 μm were measured in the same manner as in Example 1 and the apparent density, tensile strength, elongation, The depth, spread area, and ethanol permeation time were measured. A scanning electron micrograph is shown in FIG. 5, and the results of each measurement are shown in Table 2.

Comparative Example 3

As a raw material, Baxter B was sieved to a size of 75 μm or less, and thus obtained RX was used. A polyurethane elastomer was obtained in exactly the same manner as in Example 1 except that the gum RX was used in place of the gum B, and in the same manner as in Example 1, the number of pores having a pore diameter in the range of 15 μm or more and 75 μm or more, Pore number, and pore number exceeding 150 μm were measured, and the apparent density, tensile strength and elongation, hardness, depth of absorption, spreading area and ethanol permeation time were measured. A scanning electron micrograph is shown in FIG. 6, and the results of each measurement are shown in Table 2.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Porogen B C A R-15 RX SEM picture 2 3 4 5 6 Number of pores of 15μm ~ 75μm 228 444 56 56 24 Pore number of 75μm ~ 150μm 36 8 64 0 72 Number of pores exceeding 150 μm 4 0 12 0 8 Apparent density (kg / m ³ ) 160 160 160 260 160 Tensile strength (kPa) 230 205 270 558 300 Elongation (%) 290 320 310 316 280 Hardness (F type) (degrees) 52 55 50 86 50 Ethanol permeation time (sec) 37 342 22 797 6 Absorption depth (mm) 1.2 0.7 3.8 0.1 3.2 Spreading area (cm ² ) 91 89 33 37 40

As shown in Table 1 and Table 2, it was found that a group of particles having a particle diameter of less than 15 탆 was contained in an amount exceeding 10 mass% (about 80 mass%), Was used as the powder of the inorganic salt, a cosmetic sponge having a pore diameter of not less than 150 μm and a maximum diameter of not less than 150 and a bulk density of more than 200 kg / m ³ was obtained. Although this cosmetic sponge has a three-dimensional membrane structure (from SEM photographs), the ethanol permeation time is over 400 seconds. Further, since the depth of absorption is small and the impregnation amount of the cosmetic material is insufficient, the spreading area is also small, and the performance is not matched with the cosmetic sponge, so that it does not satisfy the recent request. As can be seen from this result, in the case of using a gypsum containing particles of less than 15 mu m in an amount exceeding 10 mass%, a porous article suitable for cosmetics is not obtained.

In Comparative Example 1, in which the ratio of the particle groups having a particle diameter of 15 to 75 μm was less than 35 mass% and the ratio of the particle groups exceeding 10 μm in particle diameter exceeding 10 mass% was used as the powder of the inorganic salt, Of the pores having a maximum diameter of 15 μm or more and 150 μm or less and 50% or less of the number of pores having a maximum diameter of 15 μm or more and 150 μm or less are obtained. In this cosmetic sponge, the depth of absorption of the foundation is so large that the cosmetic material is pushed into an empty space of the net (hole) and is absorbed deep inside the sponge, so that the cosmetic sponge is apt to be attached to the finger through the sponge, This is a performance that does not fit into a small, cosmetic sponge, so it does not meet recent demands.

In the comparative example 3, except that the grain size RX obtained by removing the grain size B of the grain B by a sieve was used, and the number of pores having a maximum diameter of 15 μm or more and 150 μm or less was 150 μm or less, The number of pores having a diameter of 15 μm or less and 75 μm or less is 50% or less of the number of pores having a maximum diameter of 15 μm or more and 150 μm or less. The ethanol permeation time of the cosmetic sponge is less than 10 seconds. This cosmetic sponge has a large depth of absorption, a small spreading area, insufficient amount of cosmetic material to be impregnated, and is incompatible with a cosmetic sponge, so that it does not meet recent demands.

In addition, the amount of the cetyltrienols (that is, the grains having a particle size of 75 m or less in the case of removing with the above-mentioned sieve, the amount of particles having a particle size of 15 m or more and 75 m or less in terms of the particle size distribution of the gum B in Table 1 exceeds 85% A shrinkage phenomenon was observed in the sponge after drying and an F-type hardness was 100, and a soft porous article suitable for cosmetic use was obtained. There was no.

On the other hand, a group of particles having a particle diameter of less than 15 占 퐉 of 10% by mass or less, a particle group of 15 占 퐉 or more and 75 占 퐉 or less of 35 to 85% by mass (preferably 35 to 55% In Examples 1 and 2, in which the particle size of the inorganic salt having a particle size distribution of not more than 10% by mass and not more than 10% by mass of the particle size exceeding 10% by mass was used, the ethanol permeation time was in the range of 10 seconds to less than 400 seconds, Wherein the pores having a maximum diameter of not less than 15 μm and not more than 150 μm are not less than 80% of the number of pores having a maximum diameter of not less than 15 μm and not more than 150 μm, A polyurethane elastic body having a three-dimensional membrane structure having a density of 120 to 200 kg / m ³ is obtained. The cosmetic sponge made of the polyurethane elastomer has an adequate depth of absorption, has a large spreading area, can be suitably used for application of a liquid foundation having low viscosity and low sagging, and satisfies the recent demands sufficiently.

Example 3

The outer and inner skin layers of the polyurethane elastic body obtained in Example 1 were removed by a slicing machine to obtain a sponge body having a thickness of 8 mm. The sponge body was cut with a Thompson blade, and the cutting face was polished by a rotating grindstone to obtain a cosmetic application pouch (cosmetic puff) having a thickness of 8 mm and a diameter of 60 mm.

The cosmetic sponge of the present invention is preferably used as a coating liquid for a low-viscosity cosmetic composition such as a liquid foundation in recent years. And, the polyurethane elastomer produced by the method of the present invention is preferably used for forming the cosmetic sponge of the present invention.

The polyurethane elastomer may further contain at least one selected from the group consisting of carbon blacks such as acetylene black (manufactured by Electrochemical Industries) and Ketjenblack (manufactured by Ketjen Black International), metal powder, metal oxide, carbon fiber, metal fiber, (For example, a surface resistivity of 10 ⁴ to 10 ¹⁰ Ω / sq) required for ESD safety can be imparted by blending in the step of obtaining a kneaded product, The urethane elastic body is also preferably used for rolls, wipers, swabs, etc. for the purpose of removing static electricity such as a magnetic head, a magnetic recording medium, a printed wiring board, or a liquid crystal substrate.

When a high HLB surfactant is blended in the step of obtaining a kneaded product, excellent water absorbability can be imparted. The polyurethane elastic body imparted with this water absorbing property can be used for a water cleaning after a chemical treatment process of a precision instrument or an electronic part A water absorption sponge, a scrap cleaning solution, and the like.

Claims (4)

As a three-dimensional membrane structure continuous pore elastomer,
Ethanol permeation time is in the range of 10 seconds to less than 400 seconds,
Wherein the pores having a maximum diameter of not less than 15 μm and not more than 150 μm and not more than 10 pores having a maximum diameter of more than 150 μm and not more than 15 μm and not more than 75 μm in a range of 1.0 mm × 1.0 mm, the number of not less than 80% of the maximum diameter of 15μm or more number of pores of 150μm or less, and a sponge for make-up, characterized in that the apparent density consisting of 120 ~ 200kg / m ³ polyurethane elastomer. The method according to claim 1,
Wherein the pores of the polyurethane elastic body have a substantially circular or elliptical cross-sectional shape. A step of kneading a blend containing a water-solidifying polyurethane, a solvent, a powder of a water-soluble inorganic salt and a surfactant having an HLB of less than 8.6 as a main component to obtain a kneaded product,
A step of defoaming the kneaded product to obtain a defoaming kneaded product,
A step of molding the defoaming kneaded product to obtain a molded product,
A step of putting the molded product in water or an aqueous solution and then solidifying to form a solidified product,
Eluting the inorganic salt from the solidified product in water to remove the solid salt, and
And a step of drying after the elution is removed,
Wherein the particles of the water-soluble inorganic salt have a particle group of less than 15 占 퐉 in an amount of 10 mass% or less, a particle group of 15 占 퐉 or more and less than 75 占 퐉 in a particle group of 35 to 85 mass%, a particle group of a particle diameter of 75 占 퐉 or more and 150 占 퐉 or less in a particle group of 50 mass% And a particle group of more than 10 mass% of the particles of the polyurethane. A cosmetic dispenser characterized by using the cosmetic sponge of claim 1 or 2.

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