JP5295695B2 - Thickening gelling agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thickening and gelling agent by which an oil-in-water type emulsion composition having a high viscosity can be prepared regardless of the content of a monoester component of a fatty acid ester of sucrose. <P>SOLUTION: The thickening and gelling agent contains the fatty acid ester of the sucrose obtained by adding 2-10 pts.wt. unsaturated fatty acid ester of the sucrose (e.g. sucrose oleate) containing a 14-20C unsaturated fatty acid as a constituent fatty acid to 100 pts.wt. saturated fatty acid ester of the sucrose (e.g. sucrose stearate) containing a 14-20C saturated fatty acid as a constituent fatty acid. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a thickening gelling agent, and more particularly to a thickening gelling agent using a sucrose fatty acid ester.

  Conventionally, sucrose fatty acid esters form a lamellar structure in water, and have been applied to thickener gelling agents in the fields of pharmaceuticals, cosmetics, foods, etc. by utilizing their characteristics. Usability and high gelling performance are possible.

For example, Patent Document 1 below discloses an aqueous thickening gelling agent containing a sucrose fatty acid diester having a purity of 50% or more with respect to the total sucrose fatty acid ester and an ionic surfactant. Patent Document 2 below discloses an aqueous solution containing a sucrose fatty acid diester having a purity of 50% or more based on the total sucrose fatty acid ester, an ionic surfactant, a higher fatty acid alcohol and / or a higher fatty acid. A thickening gelling agent is disclosed.
JP 05-279651 A Japanese Patent Application Laid-Open No. 07-026245

  In the technique described in the above document, it is essential that the content of sucrose fatty acid diester is 50% or more with respect to the total sucrose fatty acid ester, but it has been found that this is not necessarily the best condition. For example, when the content of the monoester component is higher than 15% even though the diester component is 50% or more, an oil-in-water emulsion composition with sufficient gel hardness cannot be obtained, and the thickening gelling agent Does not function as effectively.

  The present invention has been made in view of the above points, and is capable of preparing an oil-in-water emulsion composition having a high viscosity regardless of the content of the monoester component in the sucrose saturated fatty acid ester. An object is to provide a gelling agent.

  The present inventor has intensively studied in view of the above problems, and by adding a predetermined amount of a sucrose unsaturated fatty acid ester to a sucrose saturated fatty acid ester conventionally used as a thickening gelling agent. In order to complete the present invention, it was found that an oil-in-water emulsion composition having a high viscosity can be prepared regardless of the content of the monoester component of the sucrose saturated fatty acid ester, and that excellent gelling performance can be exhibited. It came.

  That is, the thickening gelling agent according to the present invention comprises a unsaturated fatty acid having 14 to 20 carbon atoms as a constituent fatty acid with respect to 100 parts by weight of a saturated sucrose fatty acid ester having a saturated fatty acid having 14 to 20 carbon atoms as a constituent fatty acid. It contains sucrose fatty acid ester to which 2 to 10 parts by weight of sucrose unsaturated fatty acid ester is added.

  According to the present invention, by adding a predetermined amount of a sucrose unsaturated fatty acid ester to the sucrose saturated fatty acid ester, regardless of the content of the monoester component of the sucrose saturated fatty acid ester, a high viscosity oil-in-water A mold emulsion composition can be obtained.

  Hereinafter, matters related to the implementation of the present invention will be described in detail.

  The thickening gelling agent according to the present invention contains a sucrose fatty acid ester. Sucrose fatty acid ester is a nonionic surfactant obtained by esterifying a fatty acid with a hydroxyl group of sucrose (sucrose), has high safety, and can be suitably used in pharmaceuticals, cosmetics, foods and the like.

  Among such sucrose fatty acid esters, the thickening gelling agent according to the present invention uses a sucrose saturated fatty acid ester as a main component. As the fatty acid constituting the sucrose saturated fatty acid ester, a saturated fatty acid having 14 to 20 carbon atoms is used. Specific examples include myristic acid, palmitic acid, stearic acid, and arachidic acid, which can be used alone or in combination of two or more. A saturated fatty acid having 16 to 18 carbon atoms is preferable, and stearic acid or a mixture of stearic acid and palmitic acid is more preferable. In the case of a mixture, although it does not specifically limit, it is preferable that they are stearic acid / palmitic acid = 60 / 40-90 / 10 (weight ratio).

  As this sucrose saturated fatty acid ester, what contains 50 weight% or more of diester components (sucrose saturated fatty acid diester) whose esterification degree is 2 is used preferably. Since such a sucrose saturated fatty acid ester having a high diester component forms an aggregate having a lamellar structure in the aqueous phase, the gelling effect can be enhanced. The upper limit of the content of the diester component is not particularly limited, and may be 100% by weight. Preferably it is 80 weight% or less, More preferably, it is 70 weight% or less.

  The monoester component (ester component having an esterification degree of 1) and the triester component (ester component having an esterification degree of 3) of the sucrose saturated fatty acid ester are not particularly limited. Rather, in the present invention, as shown in the examples below, even when the monoester component is 15% by weight or more, a gel with sufficient hardness can be obtained, which is advantageous in this respect. In general, it is known from the Stokes equation that the stability of an emulsion increases in proportion to the increase in viscosity. Therefore, by using the emulsifier and increasing the viscosity of the emulsion, the stability over time is improved. be able to. According to the present invention, an oil-in-water emulsion composition having a high viscosity can be obtained regardless of the monoester content.

  A sucrose saturated fatty acid ester having such an ester composition can be prepared by using a known synthesis method. In general, as a method for synthesizing a sucrose fatty acid ester, a method of reacting sucrose with a fatty acid alkyl ester (for example, fatty acid methyl) in a reaction solvent such as dimethylformamide or dimethyl sulfoxide in the presence of an alkali catalyst (solvent method: Japanese Patent Publication No. 35-13102) or a method in which water is used without using a solvent and sucrose is melted together with fatty acid soap and then reacted with a fatty acid alkyl ester in the presence of a catalyst (aqueous medium method: Japanese Patent Publication) 51-14485). After removing impurities such as unreacted sugar, fatty acid alkyl ester, and solvent from the reaction products obtained by these synthesis methods, fractionation is performed using a column or the like, and the fractions are appropriately combined and blended. Thus, a sucrose saturated fatty acid ester having the above ester composition can be prepared.

  In addition, since sucrose saturated fatty acid esters are generally marketed as a mixture of esters having different degrees of esterification, a plurality of such commercially available sucrose saturated fatty acid esters may be mixed in combination, or alternatively, commercially available sucrose saturated The fatty acid ester is fractionated using a column or the like, and the fractions are appropriately combined and blended, or these fractions are appropriately combined with the sucrose saturated fatty acid ester synthesized above or a fraction thereof. By blending in combination, a sucrose saturated fatty acid ester having the above ester composition can also be prepared.

  In the thickening gelling agent according to the present invention, a small amount of an unsaturated fatty acid ester having 14 to 20 carbon atoms as a constituent fatty acid is added to the sucrose saturated fatty acid ester. Conventionally, when an oil-in-water emulsion composition is prepared using a sucrose saturated fatty acid ester having an ester composition of 50% by weight or more of the diester component and 15% or more of the monoester component as described above, a gel with sufficient hardness is obtained. Although not obtained, by adding a small amount of sucrose unsaturated fatty acid ester, an oil-in-water emulsion composition having a high viscosity can be prepared regardless of the content of the monoester component.

  The compounding quantity of sucrose unsaturated fatty acid ester shall be 2-10 weight part with respect to 100 weight part of sucrose saturated fatty acid ester. When the blending amount is less than 2 parts by weight, the effect of adding the sucrose unsaturated fatty acid ester is hardly observed, and a stable oil-in-water emulsion composition having a high viscosity cannot be obtained. On the other hand, when the blending amount exceeds 10 parts by weight, the inherent thickening gelation performance of the sucrose saturated fatty acid ester is impaired, and a stable oil-in-water emulsion composition having a high viscosity cannot be obtained.

  Examples of the fatty acid constituting the sucrose unsaturated fatty acid ester include diunsaturated fatty acids such as myristoleic acid, palmitoleic acid, oleic acid, elaidic acid, vaccenic acid, gadoleic acid, erucic acid, and linoleic acid. Examples thereof include triunsaturated fatty acids such as saturated fatty acids and α-linolenic acid, and these can be used alone or in combination of two or more. Preferred are monounsaturated fatty acids having 16 to 18 carbon atoms, and more preferred is oleic acid.

  The ester composition of the sucrose unsaturated fatty acid ester preferably contains a monoester component having a degree of esterification of 1 as a main component. That is, a sucrose unsaturated fatty acid monoester having a monoester component content of 50% by weight or more, more preferably 70% by weight or more is preferably used. From the above, sucrose oleic acid monoester is particularly preferably used as the sucrose unsaturated fatty acid ester. In addition, adjustment of ester composition can be performed similarly to said sucrose saturated fatty acid ester.

  As the sucrose unsaturated fatty acid ester, those having an HLB of 10 or more are preferably used. HLB is more preferably 10-16.

  The mechanism for obtaining a high-viscosity emulsion is not clear, but the fatty acid site was bent in an array of regularly saturated sucrose fatty acid esters of saturated sucrose fatty acid esters in liquid crystals (or liquid crystal gels or hydrated gels). It is considered that the liquid crystal is formed with a better balance of the hydrophilic group-hydrophobic group (fatty acid part) structurally when the sucrose unsaturated fatty acid ester having a structure enters at the above ratio.

  The thickening gelling agent according to the present invention may be composed of only sucrose fatty acid ester, and together with the sucrose fatty acid ester, an ionic surfactant, glycerin fatty acid ester, propylene glycol fatty acid ester, sorbitan fatty acid Nonionic surfactants typified by esters, lecithin, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene castor oil, polyoxyethylene glyceryl ether fatty acid ester, alkyl polyglucoside Other surfactants such as may be used in combination. Examples of the ionic surfactant include, but are not limited to, anionic surfactants such as acyl glutamate, stearoyl lactate, sulfosuccinate, and ether carboxylate, alkyl ammonium salts, and organic compounds such as dimethylaminopropyl stearate. Cationic activators such as acid salts and amphoteric activators such as alkyl (amido) betaines and alkyldimethylamine oxides can be mentioned, and it is preferable to use fatty acid soaps having 12 to 22 carbon atoms.

  The thickening gelling agents include higher alcohols such as stearyl alcohol and cetyl alcohol, higher fatty acids such as stearic acid and oleic acid, sterol derivatives such as phytosterol, natural polysaccharides such as xanthan gum and carbomer.・ Synthetic thickeners ・ Water-soluble polymers, inorganic thickeners such as clay minerals and silicic anhydride, inorganic powders such as talc, kaolin and mica, organic powders such as polyamide resin powder and polystyrene powder ・ organic pigments ・Powders such as pigments, others, moisturizers, film agents, UV absorbers, sequestering agents, amino acids, pH adjusters, skin nutrients, vitamins, antioxidants, flavoring foods, cosmetics, pharmaceutical fields, etc. The material generally used in can be appropriately added.

  The thickening gelling agent according to the present invention is suitable for preparing an oil-in-water (O / W) emulsion composition (hereinafter sometimes simply referred to as “emulsified liquid”) in pharmaceuticals, cosmetics, foods and the like. Used for. The oil-in-water emulsified composition has a form in which an oil phase is dispersed in an aqueous phase, and since the dispersion medium is aqueous, there is an advantage that there is little stickiness and excellent usability. By using the above thickening gelling agent as an emulsifier for such an emulsified composition, a highly viscous gel-like oil-in-water emulsion composition can be prepared. The thickening gelling agent can also be used as a vesicle forming agent as a microcapsule of an active ingredient used in pharmaceuticals, cosmetics, foods and the like. Specific uses include, for example, use in various skin external preparations such as a lotion, a moisturizing cream, and a moisture-occlusive cream capable of suppressing moisture evaporation from the epidermis.

  Although it does not specifically limit about the manufacturing method of this oil-in-water type emulsion composition, In order to obtain a stable thing with a high viscosity, it prepares through the following process 1 and 2.

Step 1: A step of preparing an aqueous solution of thickening gelling agent of 20% by weight or more at a temperature equal to or higher than the hydrated solid-liquid crystal phase transition temperature and then cooling to a temperature lower than the hydrated solid-liquid crystal phase transition temperature to cause gelation.
Step 2: A step of mixing and emulsifying the gel, oil and water obtained in Step 1 at a temperature lower than the hydrated solid-liquid crystal phase transition temperature.

  In the above step 1, it is considered that a structural hydration gel (liquid crystal gel) is effectively formed by setting the content of the thickening gelling agent, specifically, the sucrose fatty acid ester to 20% by weight or more. The upper limit of the emulsifier content is not particularly limited, but is preferably 70% by weight or less, more preferably 60% by weight or less.

  In preparing the aqueous solution of thickening gelling agent, water is added to the thickening gelling agent, and the mixture is heated to a temperature higher than the hydration solid-liquid crystal phase transition temperature and stirred. By heating above the hydrated solid-liquid crystal phase transition temperature, the thickening gelling agent can be dissolved in water to form a liquid crystal. The heating temperature is higher than the hydrated solid-liquid crystal phase transition temperature, preferably 10-20 ° C. higher than the hydrated solid-liquid crystal phase transition temperature.

  Here, the hydrated solid-liquid crystal phase transition temperature means that the mixture containing an emulsifier (surfactant) and water is liquid from a state called a gelled hydrated solid (also called a hydrated gel or liquid crystal gel). This is the temperature at which the phase transitions to a state called liquid crystal. This phenomenon is caused by the fact that the alkyl chain part of the surfactant is crystallized when the temperature is low, but the crystalline state becomes slow above a certain temperature and the structural order is maintained due to the hydrophilic part in the same molecule. Although it is arranged, the alkyl chain portion is in a relatively free state (as if it is liquid), so that it is in a state called liquid crystal. In the case of sucrose fatty acid ester, the emulsion forms a lamellar liquid crystal structure, and the viscosity changes abruptly at a certain temperature. Therefore, the temperature at which this viscosity changes abruptly depends on the hydrated solid-liquid crystal phase. Corresponds to the transition temperature.

The hydration solid-liquid crystal phase transition temperature was measured by DSC (Differential Scanning Calorimetry) using an emulsion, and the energy entered and exited was measured under the following conditions. It is a hydrated solid-liquid crystal phase transition temperature. In addition, according to the present inventors measuring each emulsion of the following examples as a sample, since the heat generation in the temperature lowering process was the same as that in the temperature rising process, the hydrated solid-liquid crystal phase transition was It was confirmed that it occurred reversibly at a certain temperature (ie, hydrated solid-liquid crystal phase transition temperature).
[DSC] “DSC821E” (using sealed aluminum pan) made by METTER TOLEDO,
[Temperature History] Temperature rising step: 20 ° C.-80 ° C. (10 ° C./min),
Temperature decreasing step: 80 ° C.-20 ° C. (10 ° C./min).

  After stirring and dissolving at a temperature above the hydrated solid-liquid crystal phase transition temperature as described above, the thickening gelling agent aqueous solution is cooled to below the hydrated solid-liquid crystal phase transition temperature. Thereby, the thickening gelling agent aqueous solution becomes a gel-like hydrated solid. The cooling temperature is not particularly limited as long as it is lower than the hydrated solid-liquid crystal phase transition temperature, but is preferably 5-10 ° C. lower than the hydrated solid-liquid crystal phase transition temperature.

  In addition, the hydrated solid-liquid crystal phase transition temperature of the emulsion does not necessarily completely match the hydrated solid-liquid crystal phase transition temperature of the aqueous solution of the thickening gelling agent, but both can be regarded as substantially the same. Since it is considered, as described above, it is based on the hydrated solid-liquid crystal phase transition temperature of the emulsion. However, in order to make the thickening gelling agent aqueous solution gel in the first step, strictly speaking, it is preferable to cool to a temperature lower than the hydrated solid-liquid crystal phase transition temperature of the thickening gelling agent aqueous solution. .

  In Step 2, the gel-like thickening gelling agent aqueous solution obtained in Step 1, that is, a hydrated solid, is mixed with oil and water at a temperature lower than the hydrated solid-liquid crystal phase transition temperature to emulsify. (Cold emulsion) makes it possible to prepare a highly viscous oil-in-water emulsion composition (emulsion). That is, when the emulsion is heated and emulsified to a temperature higher than the hydration solid-liquid crystal phase transition temperature in accordance with a conventional ordinary method, the viscosity is lowered, although a satisfactory result is obtained. On the other hand, by emulsifying at such a low temperature as described above, the viscosity is high, the liquid can be made into a highly viscous liquid or paste, and a stable emulsion can be obtained. This is because it is in a liquid crystal state above the hydrated solid-liquid crystal phase transition temperature, so that the molecule can easily move to the water phase, oil phase or water-oil interface with relatively little energy, and the structure can easily change. However, at a temperature lower than the hydration solid-liquid crystal phase transition temperature, the sucrose fatty acid ester is present as a hydrated gel having a harder structure, and as a result, it is considered that a thickening effect is exhibited. The emulsification temperature is not particularly limited as long as it is lower than the hydrated solid-liquid crystal phase transition temperature, but is preferably 5 to 10 ° C lower than the hydrated solid-liquid crystal phase transition temperature.

  The mixing / emulsification method itself is not particularly limited. For example, an oil component may be added to the gel-like thickening gelling agent aqueous solution, stirred, then added to water, and emulsified using a homomixer or the like. Is preferred.

  The blending ratio of the thickening gelling agent aqueous solution, oil and water is not particularly limited, but the thickening gelling agent aqueous solution has a sucrose fatty acid ester concentration of 0.5 to 30% by weight in the oil-in-water emulsion composition. It is preferable to mix | blend so that it may become, More preferably, it is 1 to 10 weight%. Further, the oil content is preferably 3 to 40% by weight, more preferably 5 to 30% by weight, in the concentration in the oil-in-water emulsion composition.

  The oil component constituting the oil phase that is the dispersed phase in the oil-in-water emulsion composition is not particularly limited. For example, synthetic oils represented by silicone oils such as methyl silicone and dimethyl silicone, stearic acid and isostearic acid Higher fatty acids such as paraffin and mineral oil, hydrocarbons, ester oils such as isopropyl palmitate and isopropyl myristate, fats and oils such as animal and vegetable oils, and waxes such as beeswax and carnauba wax.

  Moreover, various water-soluble substances can be dissolved in water constituting the aqueous phase that is a continuous phase, that is, not only water but also an aqueous solution is used. For example, ethanol as a water-soluble component blended in various skin external preparations such as cosmetics and pharmaceuticals, polyhydric alcohols such as propylene glycol and butylene glycol, and sugars such as monosaccharides and oligosaccharides may be blended in water. .

  Hereinafter, the present invention will be specifically described by way of examples, but the scope of the present invention is not limited thereto.

(Preparation of sucrose saturated fatty acid ester)
A sucrose saturated fatty acid ester (stearic acid / palmitic acid = 75/25 (weight ratio)) having an ester composition shown in Table 1 below was prepared. The preparation is carried out according to the method described in “Determination of Sucrose Fatty Acid Esters by High-performance Liquid Chromatography” (J. Oleo Sci., Vol. 50, No. 4, 2001, p249-254). Was separated by HPLC, and each ester component was mixed as necessary.

Analysis of the ester composition is by gel filtration chromatography (GPC). Specifically, the conditions are as follows: column: Megapak GEL 201 (manufactured by JASCO Corporation), 20 mmφ × 500 mm × 2, eluent: tetrahydrofuran, flow rate: 3 ml / min, detector: RI, column temperature: room temperature, 500 mg of a sample and 200 mg of lauric acid (internal standard substance) were dissolved in 10 ml of tetrahydrofuran, and 60 μl of this solution was injected and analyzed. And the content of each ester component was computed by correct | amending the area ratio of the peak area of each ester part in the obtained chromatogram, and an internal standard substance with a relative sensitivity.

(Preparation of oil-in-water emulsion composition)
Step 1: Using sucrose saturated fatty acid ester and sucrose unsaturated fatty acid ester shown in Table 2 below as a thickening gelling agent, water is added to the thickening gelling agent, and from the hydrated solid-liquid crystal phase transition temperature Is heated to 80 ° C. and stirred to dissolve the thickening gelling agent, and then cooled to 40 ° C. lower than the hydrated solid-liquid crystal phase transition temperature to obtain a gelled thickening gelling agent aqueous solution. (The concentration of each thickening gel aqueous solution is as shown in Table 1).

  Process 2: At 40 degreeC lower than a hydration solid-liquid crystal phase transition temperature, the soybean-like white squeezed oil marketed as fats and oils was added and stirred to the gel-like thickening gelling agent aqueous solution obtained above (T K. Homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd./Disper blade / 1500 rpm / 5 minutes). While stirring the water to be an aqueous phase, the aqueous solution of thickening gelling agent mixed with the above-mentioned soybean white squeezed oil was added and stirred (TK homomixer / disper blade / 1500 rpm / 5 minutes). . Thereafter, an emulsification treatment (TK homomixer / homomixer blade / 8000 rpm / 5 minutes) was carried out at 40 ° C. lower than the hydrated solid-liquid crystal phase transition temperature to prepare an oil-in-water emulsion composition. .

  The contents of sucrose fatty acid ester, soybean white squeezed oil and water in each emulsified composition were as shown in Table 1 (water is described separately in step 1 and step 2, and the total amount is the emulsified composition. It is the content in the product). In addition, about the hydration solid-liquid crystal phase transition temperature of each emulsion composition, all were in the range of 45 +/- 3 degreeC.

  As the sucrose unsaturated fatty acid ester in Table 2, sucrose oleic acid monoester (“Cosmelike O-150” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) having a monoester component content of 70% by weight was used. .

(Evaluation of oil-in-water emulsion composition)
About each emulsion composition obtained above, while measuring a viscosity, the storage stability test was implemented. Each measuring method is as follows.

Viscosity: Measured at room temperature (23 ° C.) using a B-type viscometer (60 rpm, rotor Nos. 1 to 4).

Storage stability: Each emulsified composition was placed in a 100 ml bottle, capped, allowed to stand at room temperature for 7 days, and then visually evaluated for storage stability. The separation of the aqueous phase was expressed as a percentage of the total emulsion. In Table 2, “creaming” means a state where the emulsified layer is layered and inferior in storage stability showing an indication of separation.

  A result is as showing in Table 2, and it is an Example which combined predetermined amount of sucrose unsaturated fatty acid ester with sucrose saturated fatty acid ester, and the content rate of the monoester component in sucrose saturated fatty acid ester is low. Not only in Example 7, but also in Examples 1 to 6 having a high content of the monoester component, a stable emulsion having a high viscosity could be prepared.

On the other hand, in Comparative Examples 1 to 5 in which the sucrose unsaturated fatty acid ester is not blended or blended out of the predetermined range of the present invention, a sufficient gelation effect cannot be obtained and the storage stability is poor. It was.

  The thickening gelling agent according to the present invention can be suitably used for pharmaceuticals, cosmetics, foods and the like.

Claims (3)

  2 to 10 parts by weight of sucrose unsaturated fatty acid ester having 14 to 20 carbon atoms as a constituent fatty acid with respect to 100 parts by weight of sucrose saturated fatty acid ester having a fatty acid having 14 to 20 carbon atoms as a constituent fatty acid A thickening gelling agent containing an added sucrose fatty acid ester.   The thickening gelling agent according to claim 1, wherein the sucrose unsaturated fatty acid ester is sucrose oleate.   The thickening gelling agent according to claim 1 or 2, wherein the sucrose saturated fatty acid ester contains 50% by weight or more of a diester component having a degree of esterification of 2.