JP3755988B2 - Emulsification stabilizer - Google Patents

Description

【００２６】
【表２】

【００２７】
実施例１〜１０、比較例１〜９（通常の水中油型乳化機能の評価）
合成例１〜１０および比較合成例１〜５で得られたエステル化生成物について水中油型乳化組成物における能力を以下の方法により評価した。すなわち、合成例１〜１０で得たエステル化生成物（試料Ｎｏ．１〜１０）のいずれか１ｇを８０℃の水５９ｇに添加、攪拌して均一に溶解または分散させ、さらにホモミキサー（特殊機化工業（株）製、ＴＫホモミキサー）を用いて３０００ｒｐｍの攪拌下で、８０℃に加温したトリオクタン酸グリセリル（日清製油（株）製、商品名「ＴＩＯ」）４０ｇを徐々に添加した。添加終了後さらに５分間攪拌を行った後、攪拌を続けながら３０℃まで冷却し、水中油型乳化物を調整した。得られた乳化物を目盛りつきシリンダーに入れ、調整直後、および２０℃にて２４時間保存時の状態を観察した（実施例１〜１０）。この結果を表−３に示す。また、比較合成例１〜５で得たエステル化生成物（試料Ｎｏ．１１〜１５）および既存の乳化剤各種についても同様にして乳化物を調整し乳化能評価を行った（比較例１〜５および比較例６〜８）。この結果を表４及び表５に示す。さらに、前記既存乳化剤と本発明のエステル化生成物（試料Ｎｏ．１）とを併用した場合についても同様にして乳化物を調整し、乳化能評価を行った（実施例１１〜１３）。この結果を表６に示す。
【００２８】
なお、表３〜５において評価指標は次の基準および計算方法によるものである。
（乳化状態）
◎：全体に均一な乳化物
○：表面に若干油滴が認められる乳化物
△：表面にかなり油滴が認められる乳化物
×：ほとんど乳化せず
（離水率）
離水率（％）＝（離水相の重量 ÷ 乳化物中の水分重量） × １００
【００２９】
【表３】

【００３０】
【表４】

【００３１】
【表５】

［使用原料］
ポリオキシエチレンソルビタンステアラート（ＰＯＥ）：花王（株）製、商品名「レオドールＴＷ−Ｓ１２０」
ソルビタンモノオレアート：日清製油（株）製、商品名「コスモール８２」
脂肪酸：花王（株）製、商品名「ルナックＳ−９８」
グリセリン脂肪酸エステル（ＭＧ）：理研ビタミン（株）製、商品名「ポエムＳ１００」
セタノール：花王（株）製、商品名「カルコール６８」
【００３２】
【表６】

【００３３】
表３〜表６に示したデータから、本発明のエステル化生成物（試料Ｎｏ．１〜１０）は、従来の乳化剤を使用して得た乳化状態をさらに安定化させ、該乳化状態を長期に維持できることが明らかとなった。これは、比較合成例で調整したエステル化生成物（試料Ｎｏ．１１〜１５）や従来既知の乳化剤を使用して作成した水中油型乳化物に比べて顕著な効果があり、また従来既知の乳化剤を使用して作成した水中油型乳化物の乳化状態を安定化させる乳化安定化剤として本発明の生成物が有用であることを意味する。
【００３４】
実施例１４〜１９（ゲル乳化法による水中油型乳化機能の評価）
合成例１、３、５および７で得たエステル化生成物（試料Ｎｏ．１、３、５および７）のいずれか１ｇをグリセリン１０ｇ、水２ｇと８０℃で混合し、さらにディスパーミキサー（特殊機化工業（株）製）２０００ｒｐｍの攪拌下で、８０℃に加温したトリオクタン酸グリセリル（日清製油（株）製、商品名「ＴＩＯ」）３０ｇを徐々に添加した。添加終了後５分間攪拌を行いゲル状とした後、さらに８０℃に加温したイオン交換水５７ｇを徐々に攪拌下で添加した。その後攪拌しながら３０℃まで冷却し、水中油型乳化物を得た。得られた乳化物を目盛りつきシリンダーに入れ、調整直後、および２０℃にて１０日後の状態を観察した。この結果を表７に示す。
【００３５】
【表７】

表７のデータから、本発明のエステル化生成物は、ゲル乳化法による乳化が可能であり、非常に均一で安定な水中油型乳化物を形成することが確認された。
【００３６】
【発明の効果】
本発明によれば、ジペンタエリスリトール、グリセリン縮合物、炭素数６〜２０の脂肪族飽和二塩基酸および炭素数８〜２２の脂肪酸とのエステル化生成物からなる水中油型乳化組成物の乳化安定剤を提供できる。この乳化安定剤を水中油型乳化系の処方中に少量添加することで、均一かつ非常に安定性の高い水中油型乳化組成物を得ることができる。また本発明のエステル化生成物は、既知の乳化剤に添加して非常に安定な乳化状態を形成するだけではなく、単独で用いても良好な乳化状態を作ることが可能であり、安全性も極めて高い。かかる乳化安定化機能を有する本発明のエステル化生成物は、化粧品、医薬品等の身体に関わる分野の他、一般工業用としても広範囲の産業の乳化製品に応用することができ、極めて有用である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an esterification product which is blended in an oil-in-water emulsion and exhibits an emulsion stabilization function. More specifically, by blending in an emulsified composition, it has a function of remarkably improving its emulsification stability and has extremely high safety, and is used in a wide range of water such as food, cosmetics, pharmaceuticals, agricultural chemicals, and feeds. The present invention relates to an emulsion stabilizer comprising an esterification product that can be used in an oil-type emulsion composition.
[0002]
[Prior art]
Conventionally, raw materials called various emulsifiers and emulsion stabilizers have been used for the purpose of uniformly emulsifying and stabilizing water, fats and oils, hydrocarbons, or solvents. In general, an emulsifier needs to have a function of reducing the interfacial tension between greatly different substances such as water and oil so that the emulsified particles can be easily refined and kept stable. This function requires different functions depending on conditions such as the type of water and oil or solvent and the blending ratio, and the resulting emulsifiers are also different, and in many cases, an emulsifier mixture is generally obtained. Furthermore, it is required to have high safety particularly in fields related to the human body, for example, products such as foods, cosmetics, and pharmaceuticals.
[0003]
For example, there is a polyoxyethylene sorbitan fatty acid ester as an oil-in-water emulsion that has a very high emulsifying ability and is used in a wide range, but a problem in terms of safety has been pointed out. On the other hand, polyglycerol fatty acid esters with extremely high safety are not completely satisfactory in their emulsifying power.
[0004]
In a formulation system lacking in emulsion stabilization ability, an emulsion stabilizer is used as an auxiliary means. Typical examples include cetanol and cholesterol. Cetanol is selectively oriented at the interface of the emulsified particles to form a liquid crystal, and by hardening the interface, the fluidity of the entire emulsified system is lost and the emulsified state is stabilized. However, cetanol alone does not provide a sufficient stabilizing function and is easily separated due to temperature changes. Further, as a result of the hardened emulsifying system, the grain of the emulsified composition tends to be rough. On the other hand, cholesterol contributes to reducing the interfacial tension and making the emulsified particles fine, but the emulsifying system to be stabilized is limited, and the viscosity of the emulsion does not increase, so that a creaming phenomenon is likely to occur. Apart from these, there are polymer materials such as xanthan gum, carboxyethyl cellulose, and carboxyvinyl polymer that enhance the emulsion stability by increasing the viscosity of the emulsion system. These all increase the viscosity of the outer phase (water) and stabilize it, but are often avoided from feelings of use such as a paste-like or slimy feeling.
[0005]
Thus, until now, when an emulsification system was designed for a certain purpose, the whole was put together while compensating for these drawbacks by adjusting the formulation, and the required physical properties and feel were finished. However, in the range where conventional emulsification-related materials are used, it has been a very difficult task to create a prescription that is soft and fine and has excellent emulsification stability and high safety.
[0006]
In view of the actual situation, the present inventors have worked on the development of a raw material that can be used in a different position from the past in order to improve the emulsion stability in an emulsion system mainly composed of an oil-in-water type. In other words, various substances were screened with the aim of developing materials that have a function of stabilizing the emulsion by adding a small amount in a wide range of emulsion systems and that do not significantly change the physical properties of the emulsion system. As a result, the inventors have found that the functions of both a specific oligoester emulsification aid and an emulsion stabilizer are satisfied, and the emulsified state is very stabilized despite an increase in the viscosity of the emulsion. The present invention has been completed based on such findings.
[0007]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide an emulsion stabilizer having a function of making an oil-in-water emulsion system extremely stable by adding to an emulsion formulation system or without using any other emulsifier. .
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present inventors have made extensive studies, and as a result, the oligoester product obtained by esterifying dipentaerythritol, glycerin condensate, dibasic acid and fatty acid has a high emulsifying stability effect. I discovered that. As a result of further detailed examination, a great effect can be seen regardless of the use of other fatty acid parts, but dipentaerythritol, dibasic acid, and glycerin condensate, which are the core, are in a specific range ratio. It has been found that by esterifying, an unprecedented excellent emulsification stabilization function is expressed, and it has also been found that it has a synergistic effect when used in combination with other emulsifiers even in a region outside this ratio. It came to complete.
That is, the present invention includes dipentaerythritol, glycerin condensate, aliphatic saturated dibasic acid having 6 to 20 carbon atoms, linear saturated fatty acid having 8 to 22 carbon atoms, linear unsaturated fatty acid, branched fatty acid, and hydroxy fatty acid. It is an oil agent having an emulsion stabilization function comprising an esterification product obtained by esterifying one or two or more fatty acids selected from the group.
In addition, although the oil agent by this invention exhibits an emulsion stabilization function, since it has a much larger molecular weight compared with a normal emulsifier, its safety | security is also very high.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The essential raw material components for producing the esterification product of the present invention include dipentaerythritol and glycerin condensate. In the present invention, the appropriate degree of condensation of the glycerin condensate refers to an average degree of condensation of 5 or more, particularly preferably an average degree of condensation of 6 or more, more preferably about 10 glycerin condensates. Specifically, pentaglycerin, hexaglycerin, decaglycerin and the like can be exemplified, and these can be used alone or as a mixture.
[0010]
Next, the dibasic acid needs to be an aliphatic saturated dibasic acid having 6 to 20 carbon atoms. Those containing unsaturation have a reduced emulsion stabilization function, and dibasic acids having less than 6 carbon atoms reduce the stability and safety of the esterified product. Dibasic acids having more than 21 carbon atoms are difficult to obtain as industrial raw materials. Therefore, in the present invention, dibasic acids such as adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, octadecanedioic acid, and eicosanedioic acid may be used alone or in combination. Of these, preferred is eicosane diacid.
[0011]
Furthermore, it is essential that the fatty acid is a linear saturated fatty acid having 8 to 22 carbon atoms, a linear unsaturated fatty acid, a branched fatty acid, or a hydroxy fatty acid. Specific fatty acids include linear saturated fatty acids such as n-octanoic acid, n-octylic acid, n-decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, palmitooleic acid, oleic acid, linoleic acid, linolenic acid Linear unsaturated fatty acids such as acids, isooctylic acid (2-ethylhexanoic acid), isopalmitic acid (2-hexyldecanoic acid), isostearic acid (made by Emery, trade name “Emersol 875 Isostearic Acid”, made by Unikema Examples thereof include branched fatty acids such as “PRISORINE ISAC 3505” and the like, and hydroxys fatty acids such as 12-hydroxystearic acid and ricinoleic acid. In the present invention, these may be used alone or in a mixture. . Among these, desirable fatty acids are those having 16 to 18 carbon atoms, specifically, one or more selected from the group consisting of stearic acid, palmitic acid, isostearic acid, oleic acid and 12-hydroxystearic acid. It is. In the present invention, if a fatty acid having a high degree of unsaturation is used in a large amount, the storage stability of the esterification product of the present invention may be lowered, so care must be taken. When the fatty acid has less than 7 carbon atoms or more than 20 carbon atoms, the esterification product in that case is less likely to exhibit the function of stabilizing the emulsion referred to in the present invention. The maximum stabilizing function is realized when a fatty acid having 16 to 18 carbon atoms is used.
[0012]
The raw materials can be used in appropriate combination, and any of the methods described below may be employed to obtain the esterification product of the present invention. In other words, whether dipentaerythritol, glycerin condensate, dibasic acid and fatty acid are simultaneously oligoesterified, or dipentaerythritol, dibasic acid and glycerin condensate are first esterified, and then fatty acid is added to form an oligoester. Then, the glycerin condensate and the fatty acid are esterified, and further dibasic acid and dipentaerythritol are added to carry out an oligoesterification reaction or a transesterification reaction. Among these methods, the method in which dipentaerythritol, dibasic acid, and glycerin condensate are first esterified, and fatty acid is added to form an oligoester is the most preferable result when synthesis is attempted at the same ratio. Is obtained.
[0013]
The blending ratio of dipentaerythritol, glycerin condensate and dibasic acid is not particularly limited, but it is particularly preferred that the number of moles of dipentaerythritol and glycerin condensate exceeds the number of moles of dibasic acid. When the number of moles of the dibasic acid is the same or more, it is necessary to adjust the type and amount of fatty acid to be blended because the solubility in oil is reduced. Moreover, it is preferable that the molar ratio of dipentaerythritol is 0.7-0.1 mol with respect to 1 mol of a glycerol condensate. When the molar ratio of dipentaerythritol is 0.7 mol or more, the melting point is increased and the compatibility is lowered. Moreover, when it becomes 0.1 mol or less, the water separation from an emulsion will increase and stability will fall. In such a case, it is also possible to adjust with the kind and amount of dibasic acid. Therefore, the composition in which the total number of moles of dipentaerythritol and glycerin polymer is larger than the number of moles of dibasic acid, and the molar ratio of dipentaerythritol and glycerin is 0.1 to 0.7: 1. Is most excellent as an emulsion stabilizer.
In addition, the amount of fatty acid added to the mother nucleus may be less than the number of reactive hydroxyl groups, but in order to have a function as an emulsifier, among all the hydroxyl groups of dipentaerythritol and glycerin condensate, At least one must be left as an unreacted hydroxyl group. Note that this is not the case when a hydroxy fatty acid is used as the fatty acid.
[0014]
The esterification reaction is carried out in the presence or absence of an acid, an alkali or a metal catalyst, preferably in an organic solvent or / and a gas inert to the reaction at 100 to 240 ° C. for several hours to about 20 hours, While removing by-product water. The transesterification reaction is carried out at a temperature of 20 to 140 ° C. for several tens of minutes to several hours using a catalyst such as metal alcoholate or lipase. The progress of the reaction can be evaluated by measuring the acid value in the system or the composition of the acid component in the free state, and the end point of the reaction may be determined based on this.
[0015]
Although it is possible to leave a free carboxyl group in the oligoester structure without completely terminating the esterification reaction, in the present invention, it is desirable to make the ester group almost completely. The esterification reaction product or transesterification reaction product may contain unreacted dipentaerythritol, glycerin polymer, fatty acid and / or dibasic acid, in addition to by-product fatty acid, relatively low molecular weight partial ester. Since chemical compounds and the like may coexist, they are separated and removed by a known method such as washing with water, alkali deoxidation, or treatment with an adsorbent such as silica gel, and further subjected to decolorization and deodorization treatment for purification.
[0016]
The esterification product of the present invention thus obtained is a mixture in which dipentaerythritol, glycerin condensate, fatty acid and dibasic acid are oligoesterified linearly or / and branched, and is a highly viscous liquid at room temperature. It becomes waxy. The number of residual hydroxyl groups in the esterification product is required to be at least one of the hydroxyl groups of dipentaerythritol and glycerin condensate as raw materials. However, this is not the case with hydroxy fatty acids. When there is no residual hydroxyl group other than the hydroxy fatty acid, the emulsifying property is hardly exhibited in the oil-in-water emulsion composition targeted by the present invention, or the solubility and dispersibility are remarkably inferior, and the emulsion is easy. To separate. The hydroxyl value of the esterification product of the present invention can be easily calculated and adjusted from the blending ratio of raw materials, that is, the reaction molar equivalent of dipentaerythritol and glycerin condensate and the reaction molar equivalent of fatty acid and dibasic acid. It can also be adjusted by the reaction temperature, reaction time, and the amount of product water accompanying the progress of the reaction.
[0017]
The esterification product of the present invention can be added to a mixture mainly composed of a lipophilic substance and water, and if necessary, a hydrophilic substance (polyhydric alcohol, saccharide, etc.). A stable oil-in-water emulsion composition can be formed. Although not specifically limited as a lipophilic substance, hydrocarbons such as liquid paraffin, squalane and microcrystalline wax, soybean oil, sesame oil, rice germ oil, safflower oil, palm oil, olive oil, jojoba oil, macadamia nut Oil, avocado oil, evening primrose oil, castor oil, mink oil, beef tallow and other animal fats and their hardened oils and fractionated oils, carnauba wax, candelilla wax, beeswax, rice wax and other waxes, isopropyl myristate, trioctane Examples thereof include synthetic esters such as acid glyceride, dipentanoic acid neopentyl glycol ester, isononyl isononanoate, isooctyl palmitate, and silicone oil.
[0018]
0.1 to 10% by weight, preferably 1 to 5% by weight of the esterification product of the present invention is added to the lipophilic substance, the oil phase is heated to about 80 ° C., stirred and dissolved, Add to emulsified water phase at room temperature or in a heated state and emulsify. Alternatively, the esterification product of the present invention is added to the aqueous phase. Furthermore, it is possible to add the esterification product of the present invention to both the oil phase and the aqueous phase. As an emulsification method, in addition to the emulsification method as described above, sucrose, glycerin, diglycerin, polyglycerin, 1,3-butanediol, 3-methyl-1,3-butanediol, propylene glycol, dipropylene glycol, polyethylene A D phase emulsification method or a phase inversion emulsification method in which an oil phase is added to an alcohol such as glycol, hexylene glycol, or sorbitol after the addition of the esterification product of the present invention can also be used. The oil-in-water emulsion composition thus obtained is an extremely stable formulation that hardly causes separation of oil and moisture at room temperature, and the entire system maintains a uniform state.
[0019]
The emulsified composition containing an oil agent having an emulsion stabilization function of the present invention is basically composed of only oil or water and the esterification product alone or a mixture thereof. In addition, an appropriate amount of a conventionally known emulsifier can be blended with this without departing from the scope of the present invention. Although it does not specifically limit as an emulsifier, For example, polyoxyethylene and / or polyoxypropylene addition alkyl ether, polyoxyethylene and / or polyoxypropylene addition alkyl allyl ether, polyoxyethylene and / or polyoxypropylene addition alkyl ester , Nonionic surfactants such as polyoxyethylene and / or polyoxypropylene-added sorbitan fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester, polyglycerin fatty acid ester, fatty acid salt, higher alcohol sulfate ester salt, aliphatic alcohol phosphate ester Anionic surfactants such as salts, fatty acid amide sulfonates, alkyl allyl sulfonates, cationic surfactants such as aliphatic amine salts, quaternary ammonium salts, etc. It can be exemplified surfactants. In addition, components such as fatty acids, alcohols, inorganic salts, waxes, polymer compounds, pigments, dyes, and fragrances can be blended as necessary.
[0020]
【Example】
In the following synthesis examples and examples,% is based on weight.
Synthesis example 1
In a four-necked flask equipped with a stirrer, thermometer, gas blowing tube and water separator, 17.7 g (0.07 mol) of dipentaerythritol, 116 g of decaglycerin (0.15 mol, in terms of solid content), and Charge 47.6 g (0.14 mol) of eicosane diacid, add 0.1% of p-toluenesulfonic acid as a catalyst and 5% of xylene as a refluxing solvent. The esterification reaction was allowed to proceed for 6 hours at ˜200 ° C. until no decrease in acid value was observed. Further, after cooling to room temperature, 118.6 g (0.42 mol) of stearic acid was added and the reaction was performed again. After the reaction was completed, 1% each of clay and activated carbon was added, decolorized under reduced pressure, filtered, and further steamed. The deodorization process by blowing was performed, and 280 g of the esterification product of the present invention (referred to as sample No. 1) was obtained.
[0021]
Comparative Synthesis Example 1
Dipentaerythritol 25.7 g (0.10 mol), diglycerin 33.5 g (0.20 mol), eicosane diacid 68.4 g (0.19 mol), stearic acid 170.4 g (0.60 mol) ) Was used and treated in the same manner to obtain 286 g of an esterified product (Sample No. 11).
[0022]
Synthesis Examples 2-9, Comparative Synthesis Examples 2-5
The esterification product of the synthesis example (sample No. 2-9) and the comparative synthesis example (sample No. 11-15) was obtained combining various polyglycerin, a fatty acid, and a dibasic acid by the said method.
[0023]
Synthesis Example 10
In a four-necked flask equipped with a stirrer, thermometer, gas blowing tube and water separator, dipentaerythritol 17.7 g (0.07 mol), decaglycerin 116 g (0.15 mol, in terms of solid content), eicosane Charge 47.6 g (0.14 mol) of diacid and 118.6 g (0.42 mol) of stearic acid, 0.1% of p-toluenesulfonic acid as catalyst, and xylene as reflux solvent 5% was added, and the esterification reaction was carried out at 180 to 200 ° C. in a nitrogen gas stream for 7 hours until no decrease in the acid value was observed. After cooling to room temperature, 1% each of clay and activated carbon is added, decolorized under reduced pressure, filtered, and further deodorized by blowing water vapor to obtain 295 g of the esterification product (sample No. 10) of the present invention. It was.
[0024]
Tables 1 and 2 summarize the raw material composition of the esterification reaction, the properties and analytical values of the esterification product. The raw materials in the table were as follows. Moreover, the numerical value in a raw material mixing | blending shows a mole number.
Dipentaerythritol: Guangei Chemical Industry Co., Ltd., trade name “Dipentaerythritol”
Decaglycerin: Sakamoto Yakuhin Kogyo Co., Ltd., trade name “Polyglycerin # 750”
Hexaglycerin: Sakamoto Pharmaceutical Co., Ltd., trade name “Polyglycerin # 500”
Diglycerin: Sakamoto Pharmaceutical Co., Ltd., trade name “Diglycerin”
Eicosandioic acid: manufactured by Okamura Oil Co., Ltd., trade name “SL-20”
Adipic acid: Asahi Kasei Kogyo Co., Ltd., trade name “Adipic acid”
Stearic acid: product name “Lunac S-98” manufactured by Kao Corporation
Isostearic acid: manufactured by Nissan Chemical Industries, Ltd., trade name "Isostearic acid N"
Oleic acid: Nippon Seika Co., Ltd., trade name “Pamorin # 100”
n-octanoic acid: manufactured by Shin Nippon Rika Co., Ltd., trade name “Caprylic acid”
12-hydroxystearic acid: manufactured by Kawaken Fine Chemicals Co., Ltd., trade name “hydroxystearin”
[0025]
[Table 1]

[0026]
[Table 2]

[0027]
Examples 1 to 10, Comparative Examples 1 to 9 (Evaluation of ordinary oil-in-water emulsifying function)
About the esterification product obtained by the synthesis examples 1-10 and the comparative synthesis examples 1-5, the capability in an oil-in-water type emulsion composition was evaluated with the following method. That is, 1 g of any of the esterification products (sample Nos. 1 to 10) obtained in Synthesis Examples 1 to 10 was added to 59 g of 80 ° C. water and stirred to dissolve or disperse it uniformly. 40 g of glyceryl trioctanoate (manufactured by Nisshin Oil Co., Ltd., trade name “TIO”) heated to 80 ° C. with stirring at 3000 rpm using a machine chemical industry (TK homomixer) did. After completion of the addition, the mixture was further stirred for 5 minutes, and then cooled to 30 ° C. while continuing the stirring to prepare an oil-in-water emulsion. The obtained emulsion was put into a graduated cylinder, and the state after storage for 24 hours at 20 ° C. was observed immediately after adjustment (Examples 1 to 10). The results are shown in Table-3. In addition, the esterification product (samples Nos. 11 to 15) obtained in Comparative Synthesis Examples 1 to 5 and various existing emulsifiers were similarly prepared to evaluate the emulsification ability (Comparative Examples 1 to 5). And Comparative Examples 6-8). The results are shown in Tables 4 and 5. Furthermore, the emulsified product was prepared in the same manner when the existing emulsifier and the esterification product of the present invention (sample No. 1) were used in combination, and the emulsifying ability was evaluated (Examples 11 to 13). The results are shown in Table 6.
[0028]
In Tables 3 to 5, the evaluation index is based on the following criteria and calculation method.
(Emulsified state)
◎: Emulsified uniformly on the whole ○: Emulsified with some oil droplets on the surface Δ: Emulsified with considerably oil droplets on the surface ×: Almost not emulsified (water separation rate)
Water separation rate (%) = (weight of water separation phase ÷ water weight in emulsion) × 100
[0029]
[Table 3]

[0030]
[Table 4]

[0031]
[Table 5]

[Raw materials]
Polyoxyethylene sorbitan stearate (POE): manufactured by Kao Corporation, trade name “Leodol TW-S120”
Sorbitan Monoole Art: Nisshin Oil Co., Ltd., trade name “Cosmall 82”
Fatty acid: Kao Corporation, trade name “Lunac S-98”
Glycerin fatty acid ester (MG): Riken Vitamin Co., Ltd., trade name “Poem S100”
Cetanol: Product name “Calcoal 68” manufactured by Kao Corporation
[0032]
[Table 6]

[0033]
From the data shown in Tables 3 to 6, the esterification product of the present invention (Sample Nos. 1 to 10) further stabilizes the emulsified state obtained by using the conventional emulsifier, and makes the emulsified state long-term. It became clear that it can be maintained. This has a remarkable effect as compared with the esterification product (sample Nos. 11 to 15) prepared in the comparative synthesis example and the oil-in-water emulsion prepared by using a conventionally known emulsifier, and the conventionally known product. It means that the product of the present invention is useful as an emulsion stabilizer that stabilizes the emulsified state of an oil-in-water emulsion prepared using an emulsifier.
[0034]
Examples 14 to 19 (Evaluation of oil-in-water emulsification function by gel emulsification method)
Any one g of the esterification products (sample Nos. 1, 3, 5 and 7) obtained in Synthesis Examples 1, 3, 5 and 7 was mixed with 10 g of glycerin and 2 g of water at 80 ° C., and further a disper mixer (special 30 g of glyceryl trioctanoate (Nisshin Oil Co., Ltd., trade name “TIO”) heated to 80 ° C. was gradually added under stirring at 2000 rpm. After completion of the addition, the mixture was stirred for 5 minutes to form a gel, and then 57 g of ion-exchanged water heated to 80 ° C. was gradually added with stirring. Thereafter, the mixture was cooled to 30 ° C. with stirring to obtain an oil-in-water emulsion. The obtained emulsion was put into a graduated cylinder, and the state immediately after the adjustment and after 10 days at 20 ° C. was observed. The results are shown in Table 7.
[0035]
[Table 7]

From the data in Table 7, it was confirmed that the esterification product of the present invention can be emulsified by the gel emulsification method and forms a very uniform and stable oil-in-water emulsion.
[0036]
【The invention's effect】
According to the present invention, emulsification of an oil-in-water emulsion composition comprising an esterification product of dipentaerythritol, a glycerin condensate, an aliphatic saturated dibasic acid having 6 to 20 carbon atoms and a fatty acid having 8 to 22 carbon atoms. A stabilizer can be provided. A uniform and very stable oil-in-water emulsion composition can be obtained by adding a small amount of this emulsion stabilizer to the oil-in-water emulsion system. In addition, the esterification product of the present invention can be added not only to a known emulsifier to form a very stable emulsified state, but also can be used alone to form a good emulsified state, and also has safety. Extremely expensive. The esterification product of the present invention having such an emulsion stabilizing function can be applied to emulsified products in a wide range of industries as well as fields related to the body such as cosmetics and pharmaceuticals, and is extremely useful. .

Claims (9)

An emulsion stabilizer comprising an ester product obtained by esterifying dipentaerythritol, a glycerin condensate, an aliphatic saturated dibasic acid having 6 to 20 carbon atoms and a fatty acid having 8 to 22 carbon atoms. The emulsion stabilizer according to claim 1, wherein the fatty acid having 8 to 22 carbon atoms is one or more selected from the group consisting of a linear saturated fatty acid, a linear unsaturated fatty acid, a branched fatty acid, and a hydroxy fatty acid. The emulsion stabilizer according to claim 1 or 2, wherein the glycerin condensate has an average degree of polymerization of 5 to 10. The emulsion stabilizer according to any one of claims 1 to 3, wherein the total number of moles of dipentaerythritol and glycerin polymer is larger than the number of moles of the aliphatic saturated dibasic acid. The number of moles of dipentaerythritol is 0.1-0.7 mol with respect to 1 mol of a glycerol condensate, The emulsion stabilizer of any one of Claims 1-4. The emulsion stabilizer according to claim 2, wherein the linear saturated fatty acid is stearic acid and / or palmitic acid. The emulsion stabilizer according to claim 2, wherein the linear unsaturated fatty acid is oleic acid. The emulsion stabilizer according to claim 2, wherein the branched fatty acid is isostearic acid. The emulsion stabilizer according to claim 2, wherein the hydroxy fatty acid is 12-hydroxystearic acid.