JP5002124B2 - Polyglycerin fatty acid ester - Google Patents

Description

  The present invention relates to a polyglycerin fatty acid ester that can be used as a surfactant for foods, cosmetics, pharmaceuticals, and industrial purposes for the purpose of emulsification and solubilization.

  Conventionally, various compounds such as polyoxyethylene alkyl ethers, polyoxyethylene polyhydric alcohol fatty acid esters, polyoxyethylene alkylphenyl ethers and the like as emulsifiers or solubilizers, nonionic surfactants based on ethylene oxide, ionic properties Surfactants such as sorbitan fatty acid esters, sucrose fatty acid esters, polyglycerin fatty acid esters, polyglycerin condensed ricinoleic acid esters, which have surfactants and are highly safe in the food field, are known. Among them, polyglycerin fatty acid ester is the most useful surfactant because of its high versatility because it can be used for a variety of compositions and safety to the human body and the environment.

  Regarding polyglycerin fatty acid esters, polyglycerin fatty acid esters that define the degree of polymerization of polyglycerol and HLB have been reported (see Patent Document 1), but polyglycerin fatty acid esters that define the proportion of primary hydroxyl groups have been reported. Not.

On the other hand, polyglycerin used as a raw material for polyglycerin fatty acid ester is generally dehydrated and condensed under heating in the presence of a catalyst such as sodium hydroxide using glycerin as a raw material, and distilled, decolored, deodorized, and ion exchange resin as necessary. Obtained by purification by treatment. The end point of the dehydration condensation is usually determined from the result of measuring the hydroxyl value.
JP-A-6-192065

  The polyglycerol prepared in such a process is a mixture of dehydrated condensation compounds of glycerol having different structures. The cause is that glycerin has two primary hydroxyl groups and one secondary hydroxyl group, so the molecular structure of the polyglycerin produced changes depending on which hydroxyl group is involved in the reaction when glycerin condenses. Can come. The structure of polyglycerol has a great influence on the performance of polyglycerol fatty acid ester. The polyglycerol fatty acid ester currently marketed is not designed in consideration of the structure of the hydrophilic group according to the purpose of use, and therefore its performance has not been sufficiently exhibited. Information reflecting the molecular structure of polyglycerin can be obtained by various methods, but since it is a mixture as described above, strict determination of the molecular structure is meaningless. However, it is possible to increase the number of molecular species having a tendency even in a mixture by combining synthesis methods and purification methods. For example, the ratio of primary hydroxyl groups to secondary hydroxyl groups is one of them, and this can be easily confirmed by measuring a nuclear magnetic resonance spectrum as described later.

  Currently, the polyglycerin on the market has a primary hydroxyl group ratio of less than 50%, and the ester of polyglycerin and a fatty acid could not exhibit high emulsification and solubilization power. For example, when manufacturing useful substances such as fat-soluble vitamins such as vitamin E and β-carotene as beverages using existing surfactants for foods, surfactants for cosmetics such as polyoxyethylene sorbitan ester and pharmaceuticals, transparent The product could not be solubilized and a product with good storage stability could not be produced. Therefore, auxiliary agents such as ethanol had to be added in order to obtain sufficient solubilizing ability. Therefore, if a large amount of the drink is drunk, it becomes a cocoon state, which is a social problem especially in the case of young people. Furthermore, although the polyoxyethylene derivative is used as a hydrophilic emulsifier in the cosmetics industry, there are problems with safety such as skin irritation, and there is a need for an alternative. However, conventional polyglycerin fatty acid esters and sucrose are required. Fatty acid esters have insufficient emulsification, solubilization and emulsion stability performance and cannot be replaced.

  Therefore, an object of the present invention is to provide a polyglycerin fatty acid ester that makes it possible to produce a solubilized product or a stable emulsion that has been impossible with conventional surfactants.

In view of the above points, the present inventors have intensively studied to arrive at the present invention. That is, the present invention
[1] a hydroxyl value is from 770 to 120 0, and more than 50% of primary hydroxyl groups of all the hydroxyl groups, to a polyglycerol fatty acid ester and polyglycerol fatty acid is esterified or less 61.3% .

  According to the present invention, it is possible to produce a solubilized product and a stable emulsion which are impossible with conventional surfactants.

  Hereinafter, the present invention will be described in detail.

  The polyglycerin fatty acid ester of the present invention has one major characteristic in that polyglycerin having a hydroxyl value of 1200 or less and a primary hydroxyl group of 50% or more of all hydroxyl groups and a fatty acid are esterified. Have.

  By having such characteristics, the polyglycerol fatty acid ester of the present invention can be used as a surfactant having excellent solubilization performance and emulsification performance.

  In the present invention, a surfactant is a substance added for the purpose of stabilization when mixing a lipophilic substance and a hydrophilic substance, and means a substance having a strong surface activity. These substances have both a lipophilic functional group and a hydrophilic functional group in the molecule, and reduce the surface tension of water.

  In the present invention, polyglycerin refers to a substance having a hydroxyl group and an ether bond in the molecule obtained by dehydration condensation of glycerin.

  The polyglycerol used in the present invention is a polyglycerol having a primary hydroxyl group of 50% or more of all hydroxyl groups in the polyglycerol, and further improves the solubilization performance and emulsion stability of the resulting polyglycerol fatty acid ester. Therefore, the primary hydroxyl group is preferably 55% or more of polyglycerin, more preferably 60% or more of polyglycerin. Furthermore, the hydroxyl value of polyglycerol is 1200 or less, and 1100 or less is more preferable, and 1000 or less is more preferable from the viewpoint that the hydrophilicity (HLB) of the polyglycerol fatty acid ester can be adjusted according to the use. Further, from the viewpoint of workability and ease of esterification with a fatty acid, the hydroxyl value is preferably 770 or more.

  The proportion of primary hydroxyl groups among all hydroxyl groups is measured using a method of measuring a nuclear magnetic resonance spectrum (NMR) for carbon atoms. The hydroxyl value can be measured by a method known in the art.

In addition, the nuclear magnetic resonance spectrum (NMR) with respect to a carbon atom can be measured as follows. Polyglycerin 500 mg is dissolved in 2.8 ml of heavy water, and after filtration, ¹³ C-NMR (125 MHz) spectrum is obtained by gated decoupling. The peak intensity is proportional to the carbon number by the gate decoupled measurement method. The ¹³ C chemical shifts indicating the presence of primary hydroxyl groups and secondary hydroxyl groups are about 63 ppm for methylene carbon (CH ₂ OH) and about 71 ppm for methine carbon (CHOH), respectively. The abundance ratio of the primary hydroxyl group and the secondary hydroxyl group is calculated. However, the methine carbon (CHOH) indicating the secondary hydroxyl group overlaps with the methylene carbon peak further adjacent to the methine carbon bonded to the methylene carbon indicating the primary hydroxyl group, and the integral value of itself cannot be obtained. The integrated value is calculated from the signal intensity around 74 ppm of methylene carbon (CH ₂ ) adjacent to (CHOH).

  General polyglycerin is first heated under normal pressure or reduced pressure under alkaline catalyst to remove low boiling point components through gases such as nitrogen and water vapor, ion exchange resin, ion exchange. Remove ionic components such as catalysts used by membranes, remove color and odor components using adsorbents such as activated carbon, perform reduction treatment by hydrogenation, etc., or also by molecular distillation and rectification It can be purified by fractionation.

  Alternatively, when polyglycerin is produced using glycerin as a raw material as described above, many by-products such as 6-membered ring and 8-membered ring are generated due to intramolecular condensation during dehydration condensation, so that these by-products are not generated. Thus, polyglycerin containing almost no by-products can be prepared by synthesizing and purifying glycidol, epichlorohydrin, monochlorohydrin and the like as raw materials.

  Alternatively, when polyglycerin and fatty acid are reacted, generally low molecular weight polyglycerin is more reactive with fatty acid than high molecular weight polyglycerin, so if polyglycerin with a wide molecular weight distribution is used as a raw material In this case, a uniform ester cannot be produced. Therefore, for example, polyglycerol having a molecular weight distribution as narrow as possible can be prepared by a dehalogenated alkali metal salt reaction using glycerin or a partial alcoholate thereof as a raw material and a halogenated hydrocarbon or oxyhalogenated hydrocarbon.

  Alternatively, commercially available polyglycerin such as Great Oil DE-1, Great Oil DE-2, or Great Oil TR-1 manufactured by Taiyo Kagaku may be used as the polyglycerin.

  The polyglycerol whose primary hydroxyl group is 50% or more among all the hydroxyl groups used in the present invention can be obtained, for example, by devising a synthesis method or by fractional purification from commercially available polyglycerol.

  The polyglycerin prepared as described above or a commercially available polyglycerin is reacted with a reagent that selectively binds to the primary hydroxyl group, that is, a reagent that serves as a protective group for the primary hydroxyl group. Then, since the number of protective groups increases as the number of primary hydroxyl groups in one molecule of polyglycerol increases, the polarity of the polyglycerol decreases as a result. On the other hand, since a protective group is difficult to be introduced into polyglycerin containing a lot of secondary hydroxyl groups, the polyglycerin maintains its original high polarity. It is possible to separate the two using this difference in polarity. The polyglycerin after the separation can be subjected to a protecting group elimination treatment to obtain polyglycerin containing a large amount of primary hydroxyl groups.

  Examples of the reagent that selectively reacts with the primary hydroxyl group used in the present invention include chlorotriphenylmethyl, isobutene, 1-tritylpyridinium tetrafluoroborate and the like. As for polyglycerin having no secondary hydroxyl group other than 1,2-diol, a compound that forms acetonide with polyglycerin (for example, methyl isopropenyl ether, 2,2-dimethoxypropane, 2,2-diethoxypropane, Acetone, etc.) can also be used. Of these, chlorotriphenylmethane is preferred because of the ease of introduction and elimination of primary hydroxyl groups.

  The reaction ratio of polyglycerin and the reagent is appropriately adjusted according to the desired number of primary hydroxyl groups in polyglycerin, but it is preferable to use an excessive amount of the reagent in order to surely proceed the reaction. For example, the reagent is preferably used in an amount of 2 to 10 mol, more preferably 3 to 7 mol, per 1 mol of polyglycerol.

  The reaction between polyglycerin and the reagent is preferably performed in an organic solvent in order to improve the reactivity. Examples of the organic solvent include pyridine and dimethylformamide. The addition amount of the organic solvent is preferably 200 to 1000 parts by weight, more preferably 300 to 500 parts by weight with respect to 100 parts by weight of polyglycerol. In addition, when using the compound which forms polyglycerol and acetonide as a reagent, the same effect as adding a solvent can be expected by using the compound in a large excess amount.

  The reaction between polyglycerin and the reagent is preferably performed at 5 to 30 ° C, more preferably 10 to 25 ° C, from the viewpoint of the progress of the reaction and the certainty of protection.

  After the reaction, post-treatment may be performed in the same manner as a normal chemical reaction. Organic solvents such as pyridine can be removed by distillation under reduced pressure.

  A method for fractionating the desired polyglycerol from the obtained reaction product can be achieved by utilizing the chemical and physical differences of the polyglycerol into which a protecting group has been introduced. For example, the target polyglycerol can be fractionated by a method such as distillation, vacuum distillation, molecular distillation using the difference in boiling points, or the target polyglycerol can be separated using the difference in solubility in water or an organic solvent. It can also be fractionated. For example, the target polyglycerin is fractionated by dispersing the reaction product in water and extracting it with an organic solvent immiscible with water (for example, chloroform, dichloromethane, petroleum ether, hexane, benzene, toluene, ether, ethyl acetate, etc.). can do. When this fractionation method is used, a solution of an inorganic salt such as water-containing ethanol, saline, or sodium sulfate solution can be used instead of water. It is preferable to fractionate the desired polyglycerol using water and ethyl acetate.

  By removing the solvent after solvent extraction, a low-polarity polyglycerin derivative, that is, polyglycerin in which many protective groups are introduced in one molecule is obtained. Removal of the protecting group from this derivative can be carried out by a method used in general organic synthesis. For example, removal of the protecting group can be achieved by a method of allowing p-toluenesulfonic acid to act in methanol, a method of heating and stirring in an acetic acid aqueous solution, or the like. As an example, when a triphenylmethyl group is introduced into polyglycerin, a protective group is obtained by adding 2 to 3 times the amount of acetic acid aqueous solution to the obtained reaction product and stirring at 55 to 60 ° C. for 10 hours. Can be released.

  It is possible to prepare a polyglycerol having a hydroxyl value of 1200 or less by adjusting the polyglycerol reaction step as follows, for example. For example, when preparing using the glycerin polymerization method, the hydroxyl value decreases with the lapse of the polymerization reaction time. Therefore, by confirming the process of decreasing the hydroxyl value of the polyglycerol during the reaction, a polyglycerol having a hydroxyl value of 1200 or less can be obtained. Can be easily obtained.

  Fatty acids used in the present invention are particularly limited as long as they contain a carboxylic acid as a functional group obtained by hydrolyzing and extracting oils and fats extracted from natural animals and plants and purifying them with or without separation. is not. Alternatively, it may be a fatty acid obtained by chemically synthesizing petroleum or the like as a raw material. Alternatively, these fatty acids may be reduced by hydrogenation or the like, condensed fatty acids obtained by condensation polymerization of fatty acids containing hydroxyl groups, or polymerized fatty acids obtained by heat polymerization of fatty acids having unsaturated bonds. Good. The selection of these fatty acids may be appropriately determined in consideration of the desired effect. Specific examples of fatty acids used in the present invention include behenic acid, stearic acid, lauric acid, myristic acid, oleic acid, isostearic acid, palmitic acid, capric acid, caprylic acid, caproic acid, condensed ricinoleic acid, condensed 12- Examples include hydroxystearic acid, erucic acid, palmitooleic acid, linoleic acid, linolenic acid, octylic acid, octanoic acid, ricinoleic acid, 12-hydroxystearic acid and the like.

  Esterification of polyglycerol and fatty acid is performed according to a method known in the art. For example, the esterification can be performed under normal pressure or reduced pressure in the presence of an alkali catalyst, an acid catalyst, or no catalyst. Moreover, the polyglycerol fatty acid ester which has various properties can be prepared by changing the mixing amount of polyglycerol and a fatty acid. For example, when obtaining a polyglycerin fatty acid ester for use in a hydrophilic surfactant, the polyglycerin and the fatty acid are charged by calculating the weight so as to be equimolar by calculation from the hydroxyl value of the polyglycerin and the molecular weight of the fatty acid. What is necessary is just to increase the number-of-moles of a fatty acid, when obtaining the polyglyceryl fatty acid ester for using for lipophilic surfactant. The resulting polyglycerol fatty acid ester may be further purified according to the usage requirements of the product used. The purification method may be any known method and is not particularly limited. For example, adsorption treatment with activated carbon or activated clay, deodorization treatment under reduced pressure using water vapor or nitrogen as a carrier gas, washing with acid or alkali, or molecular distillation. And may be purified.

  In order to facilitate the handling of the polyglycerol fatty acid ester of the present invention obtained as described above, other components can be added. For example, ethanol, propylene glycol, glycerin, polyglycerin, water, liquid sugar, fats and oils and the like may be added to reduce the viscosity. Alternatively, the polyglycerol fatty acid ester of the present invention may be used by adding a protein such as lactose, dextrin or other polysaccharides or caseinate to a powder.

  The polyglycerin fatty acid ester of the present invention may also be used by mixing with other surfactants from the viewpoint of improving the emulsion stability. Examples of the surfactant to be mixed include nonionic surfactants such as glycerin fatty acid ester, propylene glycol fatty acid ester, and polyglycerin fatty acid ester (excluding the polyglycerin fatty acid ester of the present invention), amphoteric surfactants, and anionic interfaces. An activator, a cationic surfactant, etc. are mentioned.

  Furthermore, the polyglycerol fatty acid ester of the present invention can be easily mixed with a hydrophobic substance such as a fat-soluble vitamin such as vitamin E, an oil-soluble pigment such as β-carotene, and an oil-soluble physiologically active substance such as a highly unsaturated fatty acid. Hydrophobic substances can be solubilized and excellent emulsification stability can be imparted.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited only to this Example.

Preparation Example 1 Purification of Polyglycerin A three-necked flask equipped with a thermometer, a Dimroth, and a stirrer was charged with polyglycerin (Great Oil DE-1, Decaglycerin; hydroxyl value 890, primary hydroxyl group ratio 46 manufactured by Taiyo Kagaku Co., Ltd. .6%, secondary hydroxyl group ratio 53.4%) 200 g and pyridine 600 ml were added. To this, 370 g of chlorotriphenylmethyl (manufactured by Wako Pure Chemical Industries, Ltd.), which is a reagent that selectively reacts with a primary hydroxyl group, was added, stirred at 100 ° C. for 1 hour, returned to room temperature, and stirred for 24 hours. Further, most of the pyridine was removed from the reaction solution under reduced pressure. 800 ml of water was added to the obtained reaction product, transferred to a separatory funnel, and extracted three times with 400 ml of ethyl acetate. The ethyl acetate layers were combined and concentrated. The obtained residue (156 g) and acetic acid (300 g) were added to a three-necked flask equipped with a thermometer, a Dimroth and a stirrer, and heated under reflux for 8 hours to desorb the trimethylphenyl group. The above process was repeated, and purified polyglycerol was mixed to obtain a certain amount of polyglycerol. The obtained polyglycerol had a hydroxyl value of 886, a primary hydroxyl group ratio of 61.3%, and a secondary hydroxyl group ratio of 38.7%.

  The hydroxyl value was calculated in accordance with the 7th edition Food Additives Official “Fats and Fats Test Method” or the standard fat and oil analysis test method.

The ratio between the primary hydroxyl group and the secondary hydroxyl group was determined by spectral analysis using a nuclear magnetic resonance apparatus. That is, using a nuclear magnetic resonance apparatus ( ¹³ C-NMR) (manufactured by JEOL Ltd., JNM-A500), the ratio of primary hydroxyl groups and secondary hydroxyl groups of polyglycerol fractionated as described above was analyzed. 500 mg of the fractionated polyglycerol was dissolved in 2.8 ml of heavy water, and after filtration, ¹³ C-NMR (125 MHz) spectrum was obtained by gated decoupling. The peak intensity is proportional to the carbon number by the gate decoupled measurement method. The ¹³ C chemical shifts indicating the presence of primary hydroxyl groups and secondary hydroxyl groups are about 63 ppm for methylene carbon (CH ₂ OH) and about 71 ppm for methine carbon (CHOH), respectively. The abundance ratio of the primary hydroxyl group and the secondary hydroxyl group was calculated. However, the methine carbon (CHOH) indicating the secondary hydroxyl group overlaps with the methylene carbon peak further adjacent to the methine carbon bonded to the methylene carbon indicating the primary hydroxyl group, and the integral value of itself cannot be obtained. The integrated value was calculated from the signal intensity around 74 ppm of methylene carbon (CH ₂ ) adjacent to (CHOH).

  In addition, the value of the hydroxyl value and the ratio of primary hydroxyl group and secondary hydroxyl group in the following Preparation Examples 2 to 6 were calculated in the same manner.

Preparation Example 2 Purification of Polyglycerol Polyglycerin (Great Oil DE-2, decaglycerol;) manufactured by Taiyo Kagaku was purified in the same manner as Preparation Example 1. The resulting polyglycerol had a hydroxyl value of 883, a primary hydroxyl group ratio of 56.2%, and a secondary hydroxyl group ratio of 43.8%.

Preparation Example 3 Purification of Polyglycerin Polyglycerin manufactured by Taiyo Kagaku Co., Ltd. (Great Oil TR-1, tetraglycerin; hydroxyl value 1160, primary hydroxyl group ratio 38.5%, secondary hydroxyl group 61.5%). The resulting polyglycerol had a hydroxyl value of 1148, a primary hydroxyl group ratio of 52.5%, and a secondary hydroxyl group ratio of 47.5%.

Preparation Example 4 Purification of Polyglycerol 450 g of the residue obtained by concentrating the aqueous layer of Preparation Example 1 and 900 g of acetic acid were added to a three-necked flask equipped with a thermometer, a Dimroth and a stirrer, and heated to reflux for 8 hours. The trimethylphenyl group was eliminated. The above process was repeated, and purified polyglycerol was mixed to obtain a certain amount of polyglycerol. The resulting polyglycerol had a hydroxyl value of 893, a primary hydroxyl group ratio of 34.4%, and a secondary hydroxyl group ratio of 65.6%.

Preparation Example 5 Purification of Polyglycerin 450 g of the residue obtained by concentrating the aqueous layer portion of Preparation Example 3 and 900 g of acetic acid were added to a three-necked flask equipped with a thermometer, a Dimroth and a stirrer, and heated to reflux for 8 hours. The trimethylphenyl group was eliminated. The above process was repeated, and purified polyglycerol was mixed to obtain a certain amount of polyglycerol. The resulting polyglycerol had a hydroxyl value of 1165, a primary hydroxyl group ratio of 32.2%, and a secondary hydroxyl group ratio of 67.8%.

Preparation Example 6 Purification of Polyglycerin Polyglycerin manufactured by Taiyo Kagaku Co., Ltd. (Great Oil DI-1, diglycerin; hydroxyl value 1353, ratio of primary hydroxyl group 48.1%, secondary hydroxyl group (51.9%). The obtained polyglycerol had a hydroxyl value of 1350, a primary hydroxyl group ratio of 53.5%, and a secondary hydroxyl group ratio of 46.5%.

Example 1
126 g of polyglycerin purified in Preparation Example 1, 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing generated water under a nitrogen stream. 2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3. The acid value was calculated according to the 7th edition Food Additives Official “Fats and Fats Test Method” or the Standard Oil and Fat Analysis Test Method.

  The acid values in the following examples and comparative examples were calculated in the same manner.

Example 2
135.2 g of polyglycerin obtained in Preparation Example 1, 44.5 g of lauric acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.5.

Example 3
126 g of polyglycerin obtained in Preparation Example 2, 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.2.

Example 4
135.2 g of polyglycerin obtained in Preparation Example 2, 44.5 g of lauric acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.4.

Example 5
126 g of polyglycerin obtained in Preparation Example 3, 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing the produced water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

Example 6
135.2 g of polyglycerin obtained in Preparation Example 3, 44.5 g of lauric acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.5.

Example 7
130 g of polyglycerol obtained in Preparation Example 3, 49.5 g of myristic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing the generated water under a nitrogen stream. Thereafter, 0.2 mL of phosphoric acid was added to obtain polyglycerol myristic acid ester. The acid value of this ester was 0.5.

Example 8
126 g of polyglycerin obtained in Preparation Example 3, 54 g of oleic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain polyglycerin oleate. The acid value of this ester was 0.4.

Comparative Example 1
126 g of polyglycerin obtained in Preparation Example 4, 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

Comparative Example 2
135.2 g of polyglycerol obtained in Preparation Example 4, 44.5 g of lauric acid, and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.5.

Comparative Example 3
126 g of polyglycerin (Great Oil DE-1, decaglycerin) manufactured by Taiyo Kagaku Co., Ltd., 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask. Reaction was performed at 0 ° C., and 0.2 mL of phosphoric acid was added after the reaction to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

  The hydroxyl value of polyglycerin (Great Oil DE-1, Decaglycerin) manufactured by Taiyo Kagaku Co. was 890, the proportion of primary hydroxyl groups was 46.6%, and the proportion of secondary hydroxyl groups was 53.4%.

Comparative Example 4
Put 135.2 g of Taiyo Kagaku polyglycerin (Great Oil DE-1, Decaglycerin), 44.5 g of lauric acid, and 0.06 g of sodium hydroxide in a 300 mL four-necked flask. It reacted at 240 degreeC, removing, 0.2 mL of phosphoric acid was added after reaction, and polyglycerin lauric acid ester was obtained. The acid value of this ester was 0.5.

Comparative Example 5
126 g of polyglycerol obtained in Preparation Example 5, 54 g of stearic acid, and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

Comparative Example 6
135.2 g of polyglycerin obtained in Preparation Example 5, 44.5 g of lauric acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.5.

Comparative Example 7
135 g of polyglycerin obtained in Preparation Example 5, 49.5 g of myristic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. Thereafter, 0.2 mL of phosphoric acid was added to obtain polyglycerol myristic acid ester. The acid value of this ester was 0.5.

Comparative Example 8
126 g of polyglycerin obtained in Preparation Example 5, 45 g of oleic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain polyglycerin oleate. The acid value of this ester was 0.5.

Comparative Example 9
126 g of polyglycerin (Great Oil TR-1, Triglycerin) manufactured by Taiyo Chemical Co., Ltd., 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask, and 250% of the produced water was removed under a nitrogen stream. Reaction was performed at 0 ° C., and 0.2 mL of phosphoric acid was added after the reaction to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

  The hydroxyl value of polyglycerin (Great Oil TR-1, Triglycerin) manufactured by Taiyo Kagaku Co. was 1160, the proportion of primary hydroxyl groups was 38.5%, and the proportion of secondary hydroxyl groups was 61.5%.

Comparative Example 10
Put 135.2 g of Taiyo Kagaku polyglycerin (Great Oil TR-1, Triglycerin), 44.5 g of lauric acid and 0.06 g of sodium hydroxide into a 300 mL four-necked flask, and supply the product water under a nitrogen stream. It reacted at 240 degreeC, removing, 0.2 mL of phosphoric acid was added after reaction, and polyglycerin lauric acid ester was obtained. The acid value of this ester was 0.5.

Comparative Example 11
126 g of polyglycerol obtained in Preparation Example 6, 54 g of stearic acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 250 ° C. while removing generated water under a nitrogen stream. .2 mL of phosphoric acid was added to obtain a polyglycerol stearate ester. The acid value of this ester was 0.3.

Comparative Example 12
135.2 g of polyglycerin obtained in Preparation Example 6, 44.5 g of lauric acid and 0.06 g of sodium hydroxide were placed in a 300 mL four-necked flask and reacted at 240 ° C. while removing generated water under a nitrogen stream. After the reaction, 0.2 mL of phosphoric acid was added to obtain polyglycerol laurate. The acid value of this ester was 0.4.

Test example 1
0.4 parts by weight of the polyglycerol fatty acid ester obtained in Examples 1 to 8 or Comparative Examples 1 to 12 was added to 0.13 parts by weight of commercially available 80% purity vitamin E, heated to 80 ° C. and mixed for 10 minutes. 0.063 g of the obtained mixture was added to 100 mL of water heated to 60 ° C. and stirred for 5 minutes using a stirrer bar, and the turbidity was measured with a spectrophotometer (manufactured by Hitachi, Ltd., U-3210) at a wavelength of 650 nm. The absorbance was measured. The results are shown in Table 1.

  From Table 1, it is clear that a polyglycerin fatty acid ester using polyglycerin having a hydroxyl value of 1200 or less and a primary hydroxyl group ratio of 50% or more has an excellent solubilizing power.

Test example 2
1 part by weight of the polyglycerin fatty acid ester obtained in Examples 1 to 8 or Comparative Examples 1 to 12 is dissolved in 100 parts by weight of water, and the white soybean oil is heated to 60 ° C. while stirring at 5000 rpm with a homomixer. After adding 100 parts by weight, the mixture was stirred at 10,000 rpm for 2 minutes to obtain an O / W emulsion. The obtained emulsion was allowed to stand at 60 ° C. for 12 hours, and the O / W emulsion stability was evaluated according to the following evaluation criteria. The results are shown in Table 1.
<O / W emulsion stability>
◎: No difference from immediately after preparation ○: Oil layer separation (less than about 5% of oil content)
Δ: Oil layer separation (about 5 to 10% of oil content)
X: Oil layer separation (over about 10% of oil content)
◎ and ○ are acceptable products.

  From Table 1, it is clear that polyglycerin fatty acid ester using polyglycerin having a hydroxyl value of 1200 or less and a primary hydroxyl group ratio of 50% or more has excellent O / W emulsion stability.

Test example 3
20 parts by weight of glycerin was added to 10 parts by weight of the polyglycerin fatty acid ester obtained in Examples 2, 4, and 6 and Comparative Examples 2, 4, 6, 10 and 12, and the mixture was heated to 50 ° C. While stirring this with a glass rod, 80 parts by weight of silicone oil heated to 50 ° C. was gradually added to obtain an emulsified composition. The obtained emulsified composition was stored at 40 ° C. for one month, and the emulsion stability was evaluated according to the following evaluation criteria. The results are shown in Table 2.
<Emulsion stability>
◎: No difference from immediately after preparation ○: Cloudiness △: Oil layer separation (less than about 10% of oil content)
X: Oil layer separation (more than about 10% of oil)
◎ and ○ are acceptable products.

  From Table 2, it is clear that a polyglycerin fatty acid ester using polyglycerin having a hydroxyl value of 1200 or less and a primary hydroxyl group ratio of 50% or more has excellent emulsion stability.

  As proved in the above examples, according to the present invention, the polyglycerin fatty acid ester obtained by using polyglycerin having a hydroxyl value of 1200 or less and a proportion of primary hydroxyl group of 50% or more and a fatty acid as raw materials is the surface of water. It is clear that the tension can be greatly reduced, and it becomes possible to produce completely solubilized products and stable emulsions that have been impossible until now in the fields of food, pharmaceuticals and cosmetics.

  The polyglycerol fatty acid ester of the present invention is effectively used in the fields of foods, pharmaceuticals, and cosmetics that require solubilization, emulsification and the like.

Claims (1)

Hydroxyl value is from 770 to 120 0, and the primary hydroxyl group exceeds 50%, polyglycerol fatty acid esters and polyglycerol fatty acid is esterified at most 61.3% of all the hydroxyl groups.