JP5930314B2 - Method for producing emulsified composition - Google Patents

Description

  The present invention relates to a method for producing an emulsified composition, and more specifically to a method for producing an emulsified composition containing a fat-soluble ascorbic acid derivative that can be preferably used for cosmetics, quasi drugs and the like.

L-ascorbic acid (vitamin C) is known to have excellent pharmacological and physiological effects as cosmetic raw materials such as a melanin production inhibitory action, an antioxidant action, and a collagen synthesis promoting action.
However, since it is water-soluble, its application range for cosmetics is limited, and it is also susceptible to oxidative degradation and easily colored.
Thus, fat-soluble ascorbic acid derivatives have also been proposed in which the hydroxyl group of ascorbic acid is esterified with a long-chain fatty acid to impart fat solubility and thereby expand applications, and in addition, stability is improved ( For example, see Patent Document 1).

  On the other hand, in the field of cosmetics and the like, attempts have been made to provide a stable emulsified composition without adding a surfactant having high skin irritation (see, for example, Patent Document 2).

JP 2003-306419 A JP 2005-75817 A

Although the fat-soluble ascorbic acid derivative is more stable than ascorbic acid, it cannot be said that the yellow color change over time is sufficiently suppressed.
Moreover, since it is calculated | required to mix | blend additives, such as surfactant, as much as possible, it is desirable not only to suppress yellowing but to be a surfactant-free emulsified composition.

  Therefore, the present invention produces an emulsion composition that contains an ascorbic acid derivative, suppresses yellowing over time, and is stable without adding a surfactant that has been conventionally used. An object of the present invention is to provide a method for producing an emulsified composition.

  In order to solve the above-mentioned problems, the present inventor has intensively studied, and if the mixture containing a predetermined hydrophobized modified alkylcellulose and water together with a fat-soluble ascorbic acid derivative is subjected to high-pressure emulsification treatment, the above-described problems will occur. The inventors have found that the problem can be solved all at once, and have completed the present invention.

  That is, the method for producing an emulsified composition according to the present invention comprises the following structural formula (1):

(In the above formula (1), R ¹ , R ² and R ³ are the same or different and are a hydrogen atom, a lower alkyl group which is a methyl group or an ethyl group, a group: — [CH ₂ CH _2-k (CH ₃ ) _k O] _m H or a group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} , n is an integer of 100 to 10,000, k is an integer of 0 or 1, and m is 1 to 10. An integer, j represents an integer of 6 to 26), and a hydrophobized modified alkylcellulose always containing the group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} , and a monocarboxylic acid of ascorbic acid Including at least one fat-soluble ascorbic acid derivative selected from esters, dicarboxylic acid esters, tricarboxylic acid esters and tetracarboxylic acid esters , and water (provided that two or more higher alcohols having a melting point of 45 ° C. or higher are included in the total amount of the mixture) 0.8% to 20% by weight And a polysaccharide containing at least one of fucose, glucose, glucuronic acid, and rhamnose as a constituent monosaccharide and containing fucose and / or rhamnose in the side chain is 0.01% based on the total amount of the mixture. Excluding the case of containing 1% by weight to 1% by weight.) It comprises at least a step of high-pressure emulsification treatment of the mixture at a treatment pressure of 50 to 150 MPa .

  According to the present invention, while containing an ascorbic acid derivative, the yellowing change over time is suppressed, and a stable emulsion composition is produced without adding a surfactant as used conventionally. be able to.

  Hereinafter, preferred embodiments of the method for producing an emulsified composition according to the present invention will be described in detail. However, the scope of the present invention is not limited to these explanations, and the gist of the present invention is not limited to the following examples. Changes can be made as appropriate without departing from the scope.

[Hydrophobic-modified alkyl cellulose]
The hydrophobized modified alkyl cellulose used in the method for producing an emulsified composition of the present invention is obtained by introducing a long-chain alkyl group, which is a hydrophobic group, into a cellulose ether derivative.

  The hydrophobically modified alkyl cellulose has the following structural formula (1):

(Wherein, R ^1, R ² and R ³ are the same or different, a hydrogen atom, a lower alkyl group is a methyl group or an ethyl group, _{group: - [CH 2 CH 2-} k (CH 3) k O] m H or a group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} , n is an integer of 100 to 10,000, k is an integer of 0 or 1, m is an integer of 1 to 10, and j is be those represented by) represents an integer of 6 to 26, hydrophobizing modified alkyl cellulose, group:. always includes a _{-CH 2 CH (OH) CH 2} OC j H 2j + 1.

Of the cellulose ether derivatives serving as the base of the hydrophobically modified alkyl cellulose, it is particularly preferable to select hydroxypropylmethylcellulose from the standpoint of availability. Hydroxypropyl methylcellulose (HPMC) is the same as or different from R ¹ , R ² and R ³ in the structural formula (1), and —H, —CH ₃ or a group: — [CH ₂ CH (CH ₃ ) O] is _m H, group: - is intended to include _{[CH 2 CH (CH 3)} O] m H.

  Hydrophobized modified alkylcellulose is a product in which a long-chain alkyl group is introduced into HPMC, and can be produced, for example, by reacting HPMC with stearyl glycidyl ether in the presence of an alkali catalyst. In addition to stearyl glycidyl ether, cetyl glycidyl ether and decyl glycidyl ether may be used.

C _j H _{2j + 1} in the group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} which is a hydrophobic group introduced into the hydrophobized modified alkylcellulose is a stearyl group (—C ₁₈ H ₃₇ ). it is preferable (in this case, _{group: -CH 2 CH (OH) CH} 2 OC j H 2j + 1 is a group: a _{-CH 2 CH (OH) CH 2} OC 18 H 37).

The hydrophobically modified alkyl cellulose represented by the structural formula (1) preferably contains 0.1 to 10.0% by mass of a group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} , More preferably, the content is 0.1 to 2.0% by mass, and particularly preferably 0.1 to 1.0% by mass.

The lower alkyl group contained in the hydrophobically modified alkyl cellulose represented by the structural formula (1) is a methyl group or an ethyl group , and a methyl group is more preferable.

  The hydrophobized modified alkylcellulose represented by the structural formula (1) preferably contains 10.0 to 50.0% by mass of methyl groups, more preferably 21.5 to 30.0% by mass.

Groups contained in the hydrophobic modified alkylcellulose represented by the structural formula _{(1): - [CH 2} CH 2-k (CH 3) k O] m H , if k is 0, groups: - [ CH ₂ CH ₂ O] _m H, and when k is 1, the group: — [CH ₂ CH (CH ₃ ) O] _m H. Particularly preferred is a group when k is 1: — [CH ₂ CH (CH ₃ ) O] _m H.

The hydrophobically modified alkyl cellulose represented by the structural formula (1) preferably contains 3.0 to 20.0% by mass of a group: — [CH ₂ CH (CH ₃ ) O] _m H, 7.0 It is more preferable to contain-11.0 mass%.

Incidentally, the lower alkyl group included in the hydrophobic modified alkylcellulose, _{groups: - [CH 2 CH 2-} k (CH 3) k O] m H, and _{groups: -CH 2 CH (OH) CH} 2 OC j H The content of _{2j + 1} is a value measured by a method according to the section of the 13th revised Japanese Pharmacopoeia hydroxypropylmethylcellulose 2208.

  As an example of a hydrophobically modified alkylcellulose that satisfies these conditions, a trade name: Sangelose manufactured by Daido Kasei Kogyo Co., Ltd. can be preferably exemplified.

[Fat-soluble ascorbic acid derivative]
As the fat-soluble ascorbic acid derivative used in the present invention, one or more kinds selected from monocarboxylic acid esters, dicarboxylic acid esters, tricarboxylic acid esters and tetracarboxylic acid esters of ascorbic acid can be used. .
Among these, from the viewpoints of stability and ease of production, ascorbyl tetra-2-hexyldecanoate, ascorbyl stearate, ascorbyl palmitate, and the like are preferable, and ascorbyl tetra-2-hexyldecanoate is particularly preferable.

〔blend〕
In the method for producing an emulsified composition of the present invention, a mixture containing the hydrophobized modified alkyl cellulose, the fat-soluble ascorbic acid derivative and water is used.

  In the mixture, the blending ratio of the hydrophobically modified alkyl cellulose is preferably 0.5 to 1.0% by mass with respect to the total amount of the mixture. If the blending ratio of the hydrophobized modified alkyl cellulose is too small, the viscosity of the mixture may be too low, leading to separation. If the blending ratio is too large, the viscosity of the mixture may be too high and high-pressure emulsification may be difficult. is there.

  In the said mixture, it is preferable that the mixture ratio of a fat-soluble ascorbic acid derivative is 0.1-9.0 mass% with respect to the mixture whole quantity. If the blending ratio of the fat-soluble ascorbic acid derivative is too small, the desired effects (melanin production inhibitory action, antioxidant action, collagen synthesis promoting action, etc.) due to the addition of the fat-soluble ascorbic acid derivative may be insufficient. If the amount is too large, it may be difficult to sufficiently suppress the yellowing.

  In the said mixture, it is preferable that the mixture ratio of water is 80.0-95.0 mass% with respect to the mixture whole quantity, and it is more preferable that it is 85.0-94.0 mass%.

  In the mixture, the blending ratio of the hydrophobized modified alkyl cellulose and the fat-soluble ascorbic acid derivative is preferably 10 to 1000 parts by mass of the fat-soluble ascorbic acid derivative with respect to 100 parts by mass of the hydrophobized modified alkyl cellulose. The acid derivative is more preferably 10 to 900 parts by mass. If the blending ratio of the fat-soluble ascorbic acid derivative is relatively high (the blending ratio of the hydrophobized modified alkyl cellulose is relatively low), it may be difficult to sufficiently suppress yellowing, and the fat-soluble ascorbine If the compounding ratio of the acid derivative is relatively low (the compounding ratio of the hydrophobized modified alkyl cellulose is relatively high), the emulsion stability may be reduced, leading to separation.

  The mixture may contain components other than the three components as long as the effects of the present invention are not impaired. Examples of such other components include antiseptics such as 1,2-pentanediol. It is done.

[High pressure emulsification process]
The method for producing an emulsified composition of the present invention includes at least a step of high-pressure emulsifying the above mixture.

Prior to high-pressure emulsification, it is preferable to carry out preliminary dispersion. By performing preliminary dispersion, high efficiency of the high-pressure emulsification treatment can be expected.
As a specific method of preliminary dispersion, for example, a method in which the mixture is heated and dispersed, cooled, and then dispersed again is preferably exemplified.
As temperature in the case of heat dispersion, 50-80 degreeC is preferable, for example, and 50-60 degreeC is more preferable.
As the dispersion time, for example, the heat dispersion is preferably 5 to 10 minutes, and the dispersion after cooling is preferably 20 to 30 minutes.
As a disperser used for the preliminary dispersion, a general disperser such as a homomixer or a three-one motor can be used.

Next, the high-pressure emulsification treatment that is essentially performed in the method of the present invention can be performed by using an apparatus such as a microfluidizer (manufactured by Mizuho Kogyo Co., Ltd.) or nanoveita (manufactured by Yoshida Kikai Kogyo Co., Ltd.).
The processing pressure of the high-pressure emulsification processing is 50 to 150 MPa , and 50 to 100 MPa is more preferable. If the pressure is too low, emulsification may be insufficient, and if the pressure is too high, the viscosity becomes too low and separation may occur.
Although it does not necessarily limit as a processing temperature of a high pressure emulsification process, For example, 10-30 degreeC is preferable. If the temperature is too low, there is a risk of aggregation in the high-pressure emulsifier, and if the temperature is too high, separation may occur.
The number of high-pressure emulsification treatments is not particularly limited, but is preferably 1 to 3 times, particularly preferably 1 to 2 times. If the number of times is too large, the viscosity becomes too low and there is a risk of separation.
As described above, the viscosity of the emulsified composition is affected by the processing conditions of the high-pressure emulsification treatment such as the treatment pressure and the number of treatments, as well as a mixture of the hydrophobized modified alkyl cellulose and the fat-soluble ascorbic acid derivative. Although it is influenced also by composition of this, it is preferable to set it as the range of 1000-20000 mPa * s by selecting these suitably, and it is more preferable to set it as the range of 1000-10000 mPa * s. If the viscosity is too low, separation may occur, and if the viscosity is too high, the load on the machine during high-pressure emulsification may increase.

[Use of emulsified composition]
The emulsion composition produced as described above can be suitably used for applications such as cosmetics and quasi drugs.
The emulsified composition can be used for various applications as it is, or viscosity adjustment, pH adjustment, etc. may be performed according to each application.

EXAMPLES Hereinafter, although the manufacturing method of the emulsion composition concerning this invention is demonstrated using an Example, this invention is not limited to these Examples.
In the following, “%” means “% by mass” unless otherwise specified.

[Example 1]
Three-one motor is prepared by adding 1.0% stearoxyhydroxypropylmethylcellulose ("Sangelose-60L", manufactured by Daido Kasei Kogyo Co., Ltd.) and 5.0% preservative (1,2-pentanediol) to 91% purified water. While stirring with BL1200 (manufactured by Shinto Kagaku Co., Ltd.), heat dispersion was performed at 80 to 90 ° C. using a water bath.
After heat dispersion, cooling was performed, and then, further, 3.0% of ascorbyl tetra-2-hexyldecanoate (“VC-IP”, manufactured by Nikko Chemicals) was added, and the mixture was stirred and dispersed at room temperature for about 15 minutes. .
After dispersion, high-pressure emulsification is performed once at 75 MPa using NanoVita “Small Desktop Medialess Wet Atomizer NVC-ES007-D” (manufactured by Yoshida Kikai Kogyo Co., Ltd.) as a high-pressure emulsifier to produce an emulsified composition. did.

[Example 2]
An emulsified composition was produced in the same manner as in Example 1 except that the blending ratio of Sangelose-60L was 0.5%.

[Examples 3 to 5]
Each emulsified composition according to Examples 3 to 5 was produced in the same manner as in Example 1 except that the pressure of the high-pressure emulsification treatment with the high-pressure emulsifier was changed to 50 MPa, 100 MPa, and 150 MPa, respectively.

[Examples 6 to 8]
Each emulsified composition according to Examples 6 to 8 was produced in the same manner as in Example 1 except that the number of times of high-pressure emulsification treatment by the high-pressure emulsifier was changed to 2, 3, and 4 respectively. .

[Examples 9 to 12]
As in Example 1, except that the proportion of ascorbyl tetra-2-hexyldecanoate “VC-IP” was changed to 0.1%, 1.0%, 6.0%, and 9.0%, respectively. Each emulsion composition according to Examples 9 to 12 was produced.

[Comparative Example 1]
An emulsified composition was produced in the same manner as in Example 1 except that the high-pressure emulsification treatment was not performed.

[Comparative Examples 2 to 4]
“Sangelose-60L” was converted into xanthan gum (“Echo Gum T”, manufactured by DSP Gokyo Food & Chemical Co., Ltd.), sodium alginate (“Duck Algin NSPH ₂ ”, manufactured by Kikkoman Biochemifa Co., Ltd.), hydroxyethyl cellulose (“ Each emulsified composition according to Comparative Examples 2 to 4 was produced in the same manner as in Example 1 except that it was changed to “HEC Daicel SE850” (manufactured by Daicel Finechem Co., Ltd.).

[Comparative Example 5]
In place of “Sangelose-60L”, polyoxyethylene hydrogenated castor oil “NIKKOL HCO-20” (manufactured by Nikko Chemicals) 1.0% and polyglyceryl laurate “NIKKOL Decaglyn 1-L” (manufactured by Nikko Chemicals) 1 An emulsified composition according to Comparative Example 5 was produced in the same manner as in Example 1 except that 0.0% was used and the blending amount of purified water was changed to 90%.

[Comparative Example 6]
Purified water 69%, "VC-IP" 3%, preservative 1.80%, dipropylene glycol 6%, glycerin 5%, squalane 5%, mineral oil 5%, dimethicone 2%, behenyl alcohol 1%, glyceryl stearate (SE) 1%, polysorbate 60 0.50%, stearic acid 0.30%, pentetate 5Na 0.05%, (hydroxyethyl acrylate / acryloyldimethyltaurine Na) copolymer 1.125% The composition which mix | blended VC-IP with the cream formulation was manufactured. Note that high-pressure emulsification is not performed.

[Measurement and evaluation of physical properties and performance]
About each emulsion composition manufactured by each Example and each comparative example, various physical properties and performance were measured and evaluated by the following methods.

<Viscosity>
It was measured with a TV-10M viscometer (manufactured by Toki Sangyo Co., Ltd.).

<Appearance>
The emulsion composition was visually evaluated after preparation.

<Yellow change>
Each emulsified composition was visually observed after a predetermined time in an environment of 5 ° C. or 50 ° C., and the presence or absence of a yellow change was evaluated according to the following criteria.
◎: No yellow change is observed ○: Yellow change is hardly observed △: Yellow change is clearly recognized ×: Brown change is recognized

<Emulsification stability>
Each emulsion composition was visually observed after a predetermined time in an environment of 5 ° C. or 50 ° C., and the emulsion stability was evaluated according to the following criteria.
◎: Separation is not recognized ○: There is no problem in properties, but some oil floating is observed ×: Separation is clearly recognized

〔result〕
About each emulsification composition concerning Examples 1-12 and Comparative Examples 1-4, each physical property, the yellow change when one month passes at 50 degreeC, and the result of having measured and measured the emulsification stability are shown in the following Tables 1 and 2 Shown in

  Furthermore, the following Table 3 shows the results of evaluating the yellowing change and the emulsion stability every 6 months under the conditions of 5 ° C. or 50 ° C. for the emulsion composition according to Example 1.

  Moreover, about the emulsion composition concerning Example 1 and Comparative Examples 2-4, the yellow change to four-week progress in 50 degreeC conditions and the result of having evaluated the emulsion stability for every week are shown in Table 4 below. .

  Further, Table 5 below shows the results of evaluating the yellowing change and the emulsion stability when 2 weeks passed under the conditions of 5 ° C. or 50 ° C. for each composition according to Example 1 and Comparative Examples 5 and 6.

[Consideration of results]
(1) From the results of Examples 1 and 2 in Table 1, the effects of the present invention are sufficiently obtained when the blending ratio of the hydrophobized modified alkyl cellulose is in the range of 0.5 to 1.0% with respect to the total amount of the mixture. It was confirmed that It has also been confirmed that if the ratio exceeds 1.0%, the increase in the viscosity value increases the mechanical load during high-pressure processing, which is not preferable.

(2) From the results of Examples 1 and 3 to 5 in Table 1, it was confirmed that the effects of the present invention were sufficiently obtained when the treatment pressure of the high-pressure emulsification treatment was in the range of 50 to 150 MPa.

(3) From the results of Examples 1 and 6 to 8 in Table 1, it was found that the number of high-pressure emulsification treatments is preferably 1 to 3, particularly preferably 1 or 2 times.

(4) From the results of Examples 1 and 9 to 12 in Table 1, the blending ratio of the fat-soluble ascorbic acid derivative is in the range of 0.1 to 9.0% with respect to the total amount of the mixture, and the hydrophobized modified alkyl It was confirmed that the effects of the present invention were sufficiently obtained in the range of about 10 to 1000 parts by mass of the fat-soluble ascorbic acid derivative with respect to 100 parts by mass of cellulose.

(5) On the other hand, from the results of Comparative Example 1 in Table 2, it was found that sufficient effects could not be obtained in terms of emulsion stability unless high-pressure emulsification treatment was performed. In Example 1, it was “◎” even after 3 months (see Table 3 above), but in Comparative Example 1, it was evaluated as “◯” after 1 month. It was confirmed that the emulsification treatment had a good influence not only on the stability of emulsification but also on the suppression of yellowing.

(6) Moreover, it turned out that the effect of this invention is not acquired from the result of Comparative Examples 2-4 in Table 2, even if it uses another well-known thickener. Therefore, although the hydrophobized modified alkyl cellulose used in the present invention is conventionally known as a thickener, the effect of the present invention is not obtained just because a thickener is used. It was found that this was a peculiar effect by using a hydrophobically modified alkyl cellulose.

(7) Furthermore, from the results shown in Table 3, in the emulsion composition of the present invention, no yellowing or separation was observed even after 6 months at 5 ° C., and very high stability over time. It turns out that it has. It was also confirmed that even under severe conditions of 50 ° C., it had high temporal stability over a long period of 4 months.

(8) On the other hand, from the results shown in Table 4, the emulsified composition using other known thickeners is separated and yellow after 1 week, and is stable in terms of stability over time. It has been found that the emulsion composition of the invention is insignificant.

(9) Moreover, from the result of Comparative Example 5 in Table 5, even when other known emulsifiers were used, the evaluation was good at 50 ° C. after 2 weeks, and the evaluation was good after 4 weeks. Compared to Example 1 (see Table 4), the stability was poor in terms of suppression of yellowing. Furthermore, as shown in Table 5, in Comparative Example 5, the emulsion stability was not sufficient.

(10) In addition, when Table 5 is seen, in the composition of Comparative Example 6 in which VC-IP is blended with a general prescription, it is evaluated as Δ after 2 weeks at 50 ° C., so that the ascorbic acid derivative is It was the cause of the yellow change, and it was confirmed that the conventional general cosmetic formulation could not suppress this yellow change.

[Prescription example]
Formulation Example 1 and Formulation Example 2 using the emulsion composition of Example 1 are shown in Table 6 below.

As shown in Formulation Examples 1 and 2, it was found that by combining A, B, and C, a preparation with a better feeling of use can be obtained.
By increasing or decreasing the amount of carboxyvinyl polymer and potassium hydroxide, preparations having different viscosities can be obtained. It can also be used as a quasi-drug prescription.

  According to the method for producing an emulsified composition of the present invention, an emulsified composition having a pharmacological and physiological effect such as a melanin production inhibitory action, an antioxidant action, and a collagen synthesis promoting action by containing an ascorbic acid derivative. Thus, it can be stably produced without adding a conventionally used surfactant, and can be suitably used in the fields of cosmetics and quasi drugs.

Claims (4)

The following structural formula (1)

(In the above formula (1), R ¹ , R ² and R ³ are the same or different and are a hydrogen atom, a lower alkyl group which is a methyl group or an ethyl group, a group: — [CH ₂ CH _2-k (CH ₃ ) _k O] _m H or a group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} , n is an integer of 100 to 10,000, k is an integer of 0 or 1, and m is 1 to 10. An integer, j represents an integer of 6 to 26), and a hydrophobized modified alkylcellulose that necessarily contains the group: —CH ₂ CH (OH) CH ₂ OC _j H _{2j + 1} ;
At least one fat-soluble ascorbic acid derivative selected from monocarboxylic acid esters, dicarboxylic acid esters, tricarboxylic acid esters and tetracarboxylic acid esters of ascorbic acid;
(However, it contains two or more higher alcohols having a melting point of 45 ° C. or higher in a proportion of 0.8 wt% to 20 wt% based on the total amount of the mixture, and contains fucose, glucose, glucuronic acid, and rhamnose). the inner at least one a constituent monosaccharide, except when it contains 0.01% to 1% by weight of the polysaccharide on the mixture total amount, including fucose and / or rhamnose in a side chain.) the mixture process pressure 50 A method for producing an emulsified composition, comprising at least a step of high-pressure emulsification treatment at 150 MPa . The hydrophobically modified alkyl cellulose represented by the structural formula (1) is a lower alkyl group that is a methyl group or an ethyl group: 10.0 to 50.0% by mass, group: — [CH ₂ CH _2-k (CH _{3) k O] m H:} 3.0~20.0 wt%, and _{groups: -CH 2 CH (OH) CH} 2 OC j H 2j + 1: 0.1~10.0 is intended to include mass%, The manufacturing method of the emulsion composition of Claim 1. The group contained in the structural formula (1): The value of _{-CH 2 CH (OH) CH 2} OC j H 2j + 1 of the j is 18, the production of the emulsion composition according to claim 1 or 2 Method.   The method for producing an emulsified composition according to any one of claims 1 to 3, wherein the fat-soluble ascorbic acid derivative is a tetra fatty acid ester of ascorbic acid.