JPH1129719A - Surface coating agent, oleophilic coated article and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a surface coating agent which effects the firm adhesion or adsorption of an oleophilic substance and does not separate during operations of formulation such as emulsification, dispersing, mixing and washing by mixing an oleophilic substance which is inert to a solid having a hydrophilic surface and is usually nureactive therewith with a surface-reactive substance reactive with the solid surface and coating a powder with the obtained mixture. SOLUTION: The surface reactive substances used include unsaturated fatty acids, salts thereof, organosilicones, etc., and are exemplified by oleic acid and isostearylamine. The oleophilic substances used are organic ultraviolet absorbers, oil-soluble vitamins, etc., and are exemplified by squalane and octyltriazone. The ratio (by weight) of the surface-reactive substance to the oleophilic substance is 99:10 to 1:90. The solid having a hydrophilic solid is desirably a powder, more desirably a powder for cosmetics and is 0.01-100 μm in size. It is exemplified by starch, silica, kaolin or talc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface coating agent (coating agent) for coating a lipophilic substance which does not easily adhere to the surface of a hydrophilic solid such as a hydrophilic powder, on the surface of the solid. The present invention relates to a coated solid (lipophilic coating) such as a coated powder having a surface coated with a surface coating agent and made lipophilic, and a method for producing the same.

[0002] The surface coating agent of the present invention is capable of efficiently and easily coating (coating) the lipophilic substance on the solid surface, and comprises a coated solid (lipophilic coating) coated with the surface coating agent of the present invention. Can be used in many broad fields such as foods, pharmaceuticals, textiles and paints. In particular, the lipophilic coated powder of the present invention in which a lipophilic substance is firmly coated is useful in the cosmetics field.

[0003]

BACKGROUND ART As a lipophilic treatment agent for a solid surface for making a hydrophilic solid surface such as a hydrophilic powder lipophilic, organosilicone, organotitanium, fatty acid, polyvalent metal salt of fatty acid, Waxes, lecithin and the like are well known.

As a method for making the powder surface lipophilic with the lipophilic treatment agent, the lipophilic treatment agent is dissolved in a solvent, mixed with powder, and the lipophilic treatment agent is added to the powder surface. And a method of adsorbing the powder in an aqueous system, a method of melting and adhering by mixing and heating with the powder, and the like. According to these methods, the lipophilic substance can be easily and firmly adhered to the powder surface, and many lipophilic substances can be firmly adhered to the powder surface. The lipophilic substance can be attached to the powder surface in a molecularly dispersed state.

[0005] A method for coating a hydrophilic solid surface and dispersing it in an oil phase easily is to dissolve a lipophilic surfactant in a dispersion medium (including a solvent) and coat the obtained liquid on the surface. That is common. As such a surfactant, sorbitan fatty acid ester, oleic acid, oleylamine and the like are used. Such surface-coated powder is generally used for dispersing powder in paints, plastics, and the like.

[0006] On the other hand, the purpose of a surface coat for lipophilicizing a hydrophilic solid surface is to make the surface lipophilic so that it can be easily dispersed in oil. Organic substances are used. That is,
(A) making the surface slippery and giving lubricity to the powder,
For the purpose of (b) preventing the powders from sticking to each other and (c) suppressing the hygroscopicity of the powders, the surface coating needs to be a solid having high lubricity and high water resistance.

[0007] Solid organic substances used for such purposes include solid organic substances among the lipophilic treatment agents, stearic acid, carnauba, calcium stearate, aluminum stearate and the like. I have.

[0008] Such surface coating agents are widely used for preventing solidification of powders such as foods, fertilizers and pharmaceuticals, preventing moisture absorption of pharmaceuticals and cosmetics, and controlling reactivity in the fields of paints and the like. Recently, many organic ultraviolet absorbers are blended in cosmetics, but methods of polymerizing, encapsulating, etc. are being studied for the purpose of further enhancing the safety of the ultraviolet absorber.

[0009] In addition, for the purpose of stabilizing, sustaining and promoting the effect of active ingredients such as vitamins and plant extracts, a method of encapsulating a drug such as liposome, encapsulation with a polymeric surfactant in micelles, etc. Has been studied variously.

[0010] Further, there is known a method in which various active ingredients are absorbed into porous plastic powder so as to gradually dissolve and act on the skin.

[0011]

Many of the conventional lipophilic treatment agents cannot always sufficiently coat a hydrophilic solid surface. That is, when a powder obtained by lipophilic treatment with a lipophilic substance that is non-reactive with a solid is dispersed in oil, or when a physical force such as a homomixer is applied with an aqueous solution containing a detergent, the non-reactive lipo- The surface coat layer of the oily substance is easily peeled off.

A first object of the present invention is to solve the above-mentioned problems and to strongly adhere or adsorb a non-reactive lipophilic substance to a solid surface such as a powder, emulsifying, dispersing and mixing. ,
An object of the present invention is to provide a surface coating agent that does not peel off in a formulation step such as washing, a lipophilic coating formed by coating the same, and a method for producing a lipophilic coating.

In order to create a highly functional solid surface,
It is necessary to adhere or adsorb a large amount of the lipophilic substance firmly to the solid surface. As described above, many lipophilic substances are encapsulated in plastic, but they have the disadvantage of lacking convenience and a low encapsulation rate in capsules. It is desired that the powder does not strongly adhere to the powder and is adsorbed.

[0014] High melting point waxes are often used to lubricate powders and to provide lubricity. However, high melting point waxes have disadvantages such as easy peeling and difficulty in forming a thin film. Therefore, it is desired to form a thin and strong adsorption film.

A second object of the present invention is to provide a surface coating agent which solves the above-mentioned disadvantages of the prior art, a lipophilic coating obtained by coating the same, and a method for producing a lipophilic coating. .

[0016]

SUMMARY OF THE INVENTION A lipophilic substance which is inactive and usually does not react with a hydrophilic solid surface, and a surface reactant which reacts with the solid surface (for example, liquid fatty acids and salts thereof, organo Titanium, organosilicone, etc.)
By coating this on the powder, the surface reactant reacts with the powder, and the lipophilic substance is firmly attached or adsorbed on the powder surface via the surface reactant,
In addition, when using a high melting point wax, a crystalline substance that easily crystallizes, etc. as the lipophilic substance, it can be uniformly coated on the powder surface in a small amount, and the crystalline substance that easily crystallizes should not be crystallized. And completed the present invention.

That is, according to the present invention, at least one of the above objects can be achieved by any of the following surface coating agents, lipophilic coatings, and methods for producing the same. A surface coating agent comprising a surface reactant having a liquid organo group and a group which reacts with a hydrophilic solid surface in the same molecule, and a lipophilic substance inactive on the hydrophilic solid surface.

The above surface coating agent, wherein the surface reactant is at least one of unsaturated fatty acids and salts thereof, branched fatty acids and salts thereof, alkylamine, organotitanium, and organosilicone. The surface reactant is oleic acid,
Isostearic acid, isostearylamine, oleylamine, alkyl polyalkylene glycol ether acetate, alkoxytriisostearyl titanate, isostearylsilane, alkyl hydrogen silicone,
The above surface coating agent which is one or more of alkyltrimethoxysilane.

The lipophilic substance is an organic ultraviolet absorber,
The above surface coating agent which is a biologically active ingredient such as oil-soluble vitamins, analogs of oil-soluble vitamins, derivatives of oil-soluble vitamins, γ-oryzanol, oil-soluble plant and animal extracts. The above surface coating agent, wherein a part or all of the lipophilic substance is at least one of an alkyl silicone and an alkoxy silicone.

The above surface coating agent, wherein a part or all of the lipophilic substance is a high melting point wax. The ratio (weight ratio) of the surface reactant to the lipophilic substance is 99:10
The above surface coating agent which is 1:90.

A lipophilic coating obtained by coating a solid having a hydrophilic surface with the surface coating agent according to any one of the above. The lipophilic coating as described above, wherein the solid is a cosmetic powder.

A process for producing a lipophilic coating, comprising a coating step of coating a solid having a hydrophilic surface with the surface coating agent according to any of the above. In the present invention, the description of the numerical range includes not only both end values, but also all arbitrary intermediate values included therein.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION

[Surface Coating Agent] The surface coating agent of the present invention comprises a specific surface reactant and a specific lipophilic substance. The ratio (weight ratio) of the surface reactant to the lipophilic substance is preferably 99:10 to 1:90, and more preferably 99:30.
The ratio is 1:70, more preferably 99:50 to 1:50.

[Surface Reactant] The surface reactant has at least one liquid organo group and at least one group that reacts with a hydrophilic solid surface in the same molecule.

The liquid organo group refers to an unsaturated hydrocarbon chain having 8 or more carbon atoms (preferably having 12 to 30 carbon atoms, more preferably having 12 to 24 carbon atoms) or a branched hydrocarbon group. It is a hydrogen chain or a hydrocarbon chain having an aromatic ring. The group that reacts with the solid surface,
It is preferably a group that binds to the solid surface, and such a group includes a carboxyl group, a phosphate group, a sulfate group, a sulfone group, an amine group, a silane group, and a titanate group.

The surface reactants are preferably unsaturated fatty acids and salts thereof, branched fatty acids and salts thereof, alkylamines, organotitanium and organosilicone. Preferred specific examples include oleic acid, isostearic acid, isostearylamine, oleylamine, alkyl polyalkylene glycol ether acetate, alkoxytriisostearyl titanate, isostearylsilane, alkyl hydrogen silicone, alkyltrimethoxysilane and the like.

[Lipophilic substance] A lipophilic substance is a lipophilic substance which is inactive on the surface of a hydrophilic solid, and it is difficult to coat a solid whose surface is hydrophilic alone. However, when the coating is dispersed in the oil phase, the coating easily peels off. It does not directly react with hydrophilic solids. However, it can adhere or adsorb to the hydrophilic solid surface via the surface reactant specified in the present invention.

The term "lipophilic substance inert to the surface of a hydrophilic solid" refers to any substance having solubility in hydrocarbons such as fatty alcohols having high polarity from hydrocarbon oils. Specifically, fatty alcohols such as cetanol and isostearyl alcohol, waxes such as carnauba wax and candelilla wax, silicone derivatives having an alkyl chain in the molecule such as alkyl silicone and alkoxy silicone, and perfluorocarbon and perfluoropolyether Derivatives, UV absorbers, fragrances and bioactive ingredients. Examples of the biologically active component include biologically active components such as oil-soluble vitamins, analogs of oil-soluble vitamins, derivatives of oil-soluble vitamins, gamma oryzanol, and oil-soluble animal and plant extracts.

[Lipophilic coating] The lipophilic coating of the present invention is obtained by coating a solid having a hydrophilic surface with the surface coating agent of the present invention. That is, in the surface reactant, a group that reacts with the hydrophilic solid surface reacts with the hydrophilic solid surface, and an adsorption film (usually liquid at room temperature) composed of the surface reactant is formed on the solid surface. It is considered that the lipophilic substance inactive on the solid surface adheres or adsorbs (preferably dissolves in the adsorbing film) on the adsorbing film. Therefore, when the lipophilic coating of the present invention is dispersed in an oil phase, not all of the lipophilic substance is immediately released in the oil phase, but is gradually released over a long period or over a long period of time. In addition, even if the lipophilic coating of the present invention is dispersed in, for example, silicone or fluorine oil in which the lipophilic substance is not dissolved, the lipophilic substance is not released.

The ratio A: B of the weight A of the hydrophilic solid to the weight B of the coating layer comprising the surface coating agent of the present invention in the lipophilic coating of the present invention is preferably 99.9: 0.1 to 99.9: 0.1. 8
The ratio can be 0:20, more preferably 99: 1 to 80:20, and still more preferably 99: 1 to 90:10. In order to gradually release the lipophilic substance into the oil phase when dispersed in the oil phase, the ratio (weight ratio) of the surface reactant to the lipophilic substance in the lipophilic coating of the present invention is 99: 1 to 50:50 (more preferably 99: 1 to 7
0:30), and preferably isostearic acid is selected as the surface reactant. In order to prevent the lipophilic substance from being retained on the solid surface and being released into the oil phase when dispersed in the oil phase, the ratio (weight ratio) of the surface reactant to the lipophilic substance in the lipophilic coating of the present invention is determined. ) Is 99: 1 to 80: 2
0 (more preferably 99: 1 to 90:10).

[Solid having a hydrophilic surface] The solid having a hydrophilic surface (hydrophilic solid) is preferably a powder, more preferably a powder for cosmetics. The size of the solid having a hydrophilic surface is preferably 0.01 μm to 100 μm, more preferably 0.01 μm to 50 μm, and still more preferably 0.0 μm to 50 μm.
It is 1 μm to 10 μm.

As the powder for cosmetics, inorganic powders for cosmetics (including metal powders for cosmetics) and organic powders for cosmetics can be used. Examples of cosmetic powders include pigments such as starch, silica, kaolin, cellulose fine powder, titanium oxide, zinc oxide, talc, sericite, mica, iron oxide, and the like.

[Method for producing lipophilic coating] The method for producing the lipophilic coating of the present invention includes a coating step of coating a solid having a hydrophilic surface with the surface coating agent of the present invention. The coating film of the surface coating agent can be forcibly dried. The drying temperature and time of the surface coating agent can be appropriately determined according to the components of the surface coating agent. For example, the drying is performed at room temperature to 200 ° C. for 1 hour.

[0034]

【Example】

[Example 1] Squalane was adhered to the surface of talc (hydrophilic solid) using butoxytriisostearoyl titanate (a surface reactant) and squalane (a lipophilic substance) according to the formulation in Table 1, and the talc was mixed with squalane. Coated. Specifically, as shown in Table 1, 100 parts by weight of talc and a predetermined amount of a surface reactant and a lipophilic substance were thoroughly mixed in a Henschel mixer for 10 minutes, then taken out, dried at 100 ° C. for 1 hour, and dried. did.

<Measurement of sticking ratio of lipophilic substance to hydrophilic solid> One gram of the sample was dispersed in 100 g of hexane, and the mixture was allowed to stand with gentle stirring for 15 minutes, and squalane dissolved in the supernatant was subjected to GLC ( (Gas / liquid chromatography). This result (the recovery rate of squalane by hexane (% is% by weight))
Are shown in Table 1. The smaller the recovery rate of squalane by hexane, the higher the sticking rate of the lipophilic substance to the hydrophilic solid. Therefore, this example shows that squalane is firmly attached to the hydrophilic solid.

Comparative Example 1 Example 1 was repeated except that stearic acid, a typical treating agent, was used instead of the surface reactant.
The talc was coated with squalane in the same manner as described above. Further, in the same manner as in Example 1, the sticking rate of the lipophilic substance to the hydrophilic solid (recovery rate of the lipophilic substance by hexane) was measured.
Table 1 shows the recovery rate of squalane by hexane.

[0037]

[Table 1]

Example 2 Squalane (lipophilic substance) was coated on powder (talc) and fixed to squalane in the same manner as in Example 1 except that the following surface reactants were used as surface reactants. The rate was measured. The surface coating agent was constant at 1% by weight of the powder, and squalane (lipophilic substance) was constant at 50% by weight of the surface reactant. The results are shown below.

Example 2-1 Squalane was coated on a powder in the same manner as in Example 1 except that oleic acid was used as a surface reactant and the weight ratio of each component was as described above. The recovery of squalane was 13%. [Example 2-2] Squalane was coated on a powder in the same manner as in Example 1 except that isostearic acid was used as a surface reactant and the weight ratio of each component was changed as described above. The recovery of squalane was 20%.

Example 2-3 Squalane was coated on a powder in the same manner as in Example 1 except that isostearylamine was used as a surface reactant and the weight ratio of each component was as described above. The recovery of squalane was 10%. [Example 2-4] Squalane was coated on the powder in the same manner as in Example 1 except that butoxytriisostearyl titanate was used as a surface reactant and the weight ratio of each component was changed as described above. The recovery of squalane was 4%.

Comparative Example 2-1 Talc was coated with squalane in the same manner as in Example 2 except that squalane (a comparative example without a treating agent) was used instead of the surface reactant. The recovery of squalane was 100%. [Comparative Example 2-2] Talc was coated with squalane in the same manner as in Example 2 except that stearic acid was used instead of the surface reactant. The recovery of squalane was 95%.

Example 3 As a lipophilic substance, an ultraviolet absorber (octyltriazone (Euinal T-150, BA
SF)), butoxyisostearoyl titanate as the surface reactant, and the weight of the ultraviolet absorber:
Weight of butoxyisostearoyl titanate = 40: 6
5% by weight (5% by weight of the total weight of the coated powder) of an ultraviolet absorber is adhered to the surface of rutile type titanium (hydrophilic solid) having a particle diameter of 100 microns in the same manner as in Example 1 except that the value is set to 0. Then, the rutile type titanium was coated with an ultraviolet absorber. Then, the fixing rate of the ultraviolet absorbent was measured. That is, the first embodiment
The ultraviolet absorbent eluted in the hexane phase was measured in the same manner as in the above, but was not eluted.

Example 4 <Preparation of Sample> 100 g of sericite having a particle size of 8 μm, which is a hydrophilic solid, was dispersed in 2 kg of water, and 0.5 g of aluminum chloride was added thereto and stirred well. To this, 10 g of a surface coating agent having the following formulation is added and further stirred well. The stirring is stopped, the mixture is filtered, and the surface-treated powder is taken out and dried to obtain a sample.

<Surface Coating Agent> 20 parts by weight of ascorbyl dipalmitate, which is a lipophilic substance, 20 parts by weight of sodium polyoxypropylene glycol (8 mol) isostearyl ether acetate, which is a surface reactant, and 60 parts by weight of purified water Was heated and stirred well to obtain a transparent gel surface coating agent.

<Measurement of sticking ratio of lipophilic substance to hydrophilic solid> 1 g of the sample was dispersed in 100 g of hexane,
The supernatant was taken out over time with good stirring, and the amount of eluted ascorbyl dipalmitate (lipophilic substance) was measured by high performance liquid chromatography (HPLC). The results are shown in Table 2 as the cumulative elution amount with respect to time. The elution amount was shown as a ratio (% by weight) to the added amount. According to Table 2, it can be seen that ascorbyl dipalmitate elutes gradually.

[0046]

[Table 2]

Example 5 A mixture of 70 parts by weight of a lipophilic substance (limonene) and 30 parts by weight of isostearylamine (surface reactant) was added to silica fine particles (hydrophilic solid) in an amount of 10% by weight (silica fine particles). And 10% by weight of the total weight of the mixture), and the silica fine particles are coated with the mixture using a Henschel mixer. This was transferred to an open container and left in a car. When only fragrance is attached to silica fine particles,
Compared to the loss of fragrance in one week, the fragrance continued for one week or more.

Example 6 10% by weight of carnauba wax (lipophilic substance), 40% by weight of an ultraviolet absorber (octyl triazone (Euinal T-150, manufactured by BASF)) (lipophilic substance), and butoxy A surface coating agent consisting of 50% by weight of triisostearoyl titanate (surface reactant) was applied to titanium (hydrophilic solid) in the same manner as in Example 1.
Was coated with 7% by weight (7% by weight of the total weight of titanium). As a result, a powder having lubricity and no elution of the ultraviolet absorber was obtained.

Example 7 Carnauba wax (lipophilic substance) 10% by weight and β-carotene (lipophilic substance) 20
Wt% and isostearyl silane (surface reactant) 70
A 5% by weight (5% by weight of the total weight of the silica fine particles) was coated on the silica fine particles (hydrophilic solid) in the same manner as in Example 1 with a surface coating agent consisting of 5% by weight. This coated powder is 2
There was no change in hue when blended into the cream over the years.

[0050]

The surface coating agent according to claims 1 to 7 of the present invention comprises a surface reactant having a liquid organo group and a group capable of reacting with a hydrophilic solid surface in the same molecule, and a hydrophilic solid surface. Since it is made of an inert lipophilic substance, the following basic effects can be exerted at the same time.

The lipophilic substance can be firmly adhered or adsorbed on the solid surface, and the lipophilic substance adheres to the solid surface even after a formulation step such as emulsification, dispersion, mixing and washing. High oily substance fixation rate. Many lipophilic substances can be easily and firmly adhered or adsorbed to solids. Since the solid surface can be uniformly coated with the crystalline lipophilic substance in a molecularly dispersed state, a thin and strong adhesion or adsorption film can be easily formed.

The surface coating agent according to claims 2 to 7 of the present invention comprises:
With each configuration, the above-described basic effects are remarkable.

Since the lipophilic coating according to claim 8 of the present invention is formed by coating a hydrophilic solid on the surface with the surface coating agent of the present invention, the amount of lipophilic substance to be released is controlled as follows. The basic effect that can be achieved. [Release] When the lipophilic coating of the present invention is dispersed in oil, the lipophilic substance can be gradually released into the oil.
Therefore, when a lipophilic coating using a biologically active ingredient such as an oil-soluble vitamin as a lipophilic substance is applied to the skin, the active ingredient is gradually released to the skin to maintain the effect. .

The strength of the sustained release effect at this time can be adjusted by the amount of surface reactants (particularly, organosilicone, organotitanium) in the lipophilic coating of the present invention. That is, the release rate of the lipophilic substance can be reduced by increasing the ratio of the surface reactant to the lipophilic substance.

[Detoxification] The lipophilic coating of the present invention can firmly adhere or adsorb a lipophilic substance on a solid surface. Therefore, even when a substance that does not have a favorable effect on the living body, such as an ultraviolet absorber or a dye, is used as the lipophilic substance, the substance can be stopped on the solid surface, and the safety of the lipophilic coating of the present invention can be enhanced.

In particular, even when a substance having a possibility of adversely affecting the living body such as an organic ultraviolet absorber is used as the lipophilic substance, when the content of the surface reactant (particularly, organotitanium) with respect to the lipophilic substance is large, Even when the lipophilic coating of the present invention is applied to the skin, the lipophilic substance can be stopped on the solid surface and prevented from transferring to the skin, so that the safety of the lipophilic coating of the present invention can be improved. Can be.

[Prevention of Crystallization] When a lipophilic substance such as β-carotene or γ-oryzanol, which has a low solubility in oil and easily crystallizes, is used as the lipophilic substance in the lipophilic coating of the present invention, the substance is converted into a molecule. Since these substances can be stopped on the solid surface, crystallization of these substances can be prevented.

According to the lipophilic coating of the ninth aspect of the present invention, the basic effect is remarkable due to the configuration.

The method for producing a lipophilic coating according to claim 10 is as follows:
Since the method includes a coating step of coating a solid whose surface is hydrophilic with the surface coating agent of the present invention, the lipophilic coating of the present invention can be easily produced.

Claims (10)

[Claims] 1. A surface comprising a surface reactant having, in the same molecule, a liquid organo group and a group which reacts with a hydrophilic solid surface, and a lipophilic substance inert to the hydrophilic solid surface. Coating agent. 2. The method according to claim 1, wherein the surface reactant is at least one of unsaturated fatty acids and salts thereof, branched fatty acids and salts thereof, alkylamine, organotitanium, and organosilicone. Surface coating agent. 3. The method of claim 1, wherein the surface reactant is oleic acid, isostearic acid, isostearylamine, oleylamine,
The surface coat according to claim 1, wherein the surface coat is at least one of an alkyl polyalkylene glycol ether acetate, an alkoxytriisostearyl titanate, an isostearylsilane, an alkyl hydrogen silicone, and an alkyltrimethoxysilane. 4. Agent. 4. The lipophilic substance is an organic ultraviolet absorbent,
4. It is one or more of biologically active components such as oil-soluble vitamins, analogs of oil-soluble vitamins, derivatives of oil-soluble vitamins, γ-oryzanol, oil-soluble animal and plant extracts. The surface coating agent according to any one of the above. 5. The surface coating agent according to claim 1, wherein a part or all of the lipophilic substance is at least one of an alkyl silicone and an alkoxy silicone. 6. The surface coating agent according to claim 1, wherein a part or all of the lipophilic substance is a high melting point wax. 7. The surface coating agent according to claim 1, wherein the ratio (weight ratio) of the surface reactant to the lipophilic substance is 99:10 to 1:90. . 8. A lipophilic coating, wherein the surface is coated with a hydrophilic solid by the surface coating agent according to any one of claims 1 to 7. 9. The lipophilic coating according to claim 8, wherein the solid is a cosmetic powder. 10. A method for producing a lipophilic coating, comprising a coating step of coating a hydrophilic solid on the surface with the surface coating agent according to any one of claims 1 to 7.