JP2005132959A - Siloxane gel and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a siloxane compound gelatinizer enabling a siloxane compound to be gelatinized in small addition amounts, to provide a method for easily producing a siloxane compound gel by merely adding the gelatinizer to a siloxane compound at room temperature without needing heating or cooling, and to obtain such a new siloxane compound gel neither causing gel strength drop nor melting even if heated. <P>SOLUTION: The siloxane compound gelatinizer comprises an alkaline earth metal salt of a resin acid. The siloxane compound gel is obtained by gelatinizing (A) a siloxane compound containing at least two silicon atoms with this gelatinizer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a gelling agent for a siloxane compound, a gel of a siloxane compound (A), and a method for producing the same. More specifically, the present invention relates to a gelling agent obtained by adding a solution containing an alkaline earth metal salt of a resin acid as an active ingredient to a siloxane compound containing at least two silicon atoms and a method for producing the same.

Siloxane compounds have excellent heat resistance, cold resistance, weather resistance, water repellency, electrical characteristics, etc., so they can be used in various applications such as cosmetics, quasi drugs, insulating materials, lubricants, inks, and other viscosity modifiers. In particular, cyclic siloxanes such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane give a smooth and non-sticky feel, and have excellent gas permeability and water repellency. It is a material used as a cosmetic ingredient because it can form a uniform film with mixed ingredients.

  However, siloxane compounds, particularly octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane, have a drawback that they themselves have low viscosity and high fluidity, and cannot be used in large quantities as cosmetic ingredients. For this reason, increasing the viscosity of the siloxane compound and reducing the fluidity is particularly effective as a cosmetic, so a method for gelling the siloxane compound is required.

Therefore, as a method for gelling cyclic siloxane, there has been proposed a method for gelling using two types of compounds, partial fatty acid ester of dextrin and inulin and / or partial fatty acid ester of hydrolyzed inulin (Patent Document 1 and Patent Document 2) requires two kinds of compounds in the method, and it is necessary to finely adjust the esterification rate of the partial fatty acid ester of dextrin and the partial fatty acid ester of inulin and / or hydrolyzed inulin, The synthesis of the compound is complicated, and furthermore, it cannot be gelled unless these two kinds of compounds are used in a certain ratio.

In addition, in this method, it is necessary to add to the cyclic siloxane gel compound or a cosmetic composition containing them, once to dissolve by heating, and then to cool and gel, and the operation is complicated and its application is very Limited. Furthermore, when the produced gel is heated again, there is a fatal defect that the gel strength is lowered or the gel is dissolved.

  In addition, although this inventor has proposed about the organic gelling agent previously, it has not examined about applying the said gelling agent to a siloxane compound. (Patent Document 3)

JP 2002-193741 A JP 2002-193747 A JP 2003-41236 A

  The present invention provides a gelling agent for a siloxane compound that can gel a siloxane compound with a low addition amount, and can be easily gelled only by adding to a gelation object at room temperature without heating and cooling. It is an object of the present invention to provide a method for producing a gel of a siloxane compound that can be converted into a gel, and to provide a novel gel of a siloxane compound that does not decrease in gel strength or dissolve even when heated.

  In order to achieve such an object, the present inventor has intensively studied and found that the object can be achieved by using an alkaline earth metal salt of a resin acid.

  That is, the present invention relates to a gelling agent for a siloxane compound characterized by containing an alkaline earth metal salt of a resin acid; a siloxane compound (A) containing at least two silicon atoms is gelled for the siloxane compound. A gel obtained by gelling with an agent; a method for producing a gel comprising adding a gelling agent for a siloxane compound to a siloxane compound (A) containing at least two silicon atoms.

  According to the gelling agent for siloxane compounds of the present invention, the siloxane compound can be gelled by adding a small amount. Moreover, the gel of the siloxane compound obtained by using the said gelling agent is a novel useful gel which does not fall in intensity | strength or melt | dissolve even if it heats unlike the gel of the conventional siloxane compound. Utilizing the effects of the gel of the present invention, it is used in a very wide range of fields such as sustained release agents such as cosmetics, quasi drugs, pharmaceuticals, agricultural chemicals, and fragrances, viscosity modifiers such as insulating materials, lubricants, inks, and paints. be able to. In particular, cyclic siloxane compound gels such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane provide a smooth, non-sticky feel, excellent gas permeability and water repellency, and form a uniform film with other mixed components. Therefore, it is suitable for cosmetics.

The gelling agent for siloxane compounds of the present invention contains an alkaline earth metal salt of a resin acid as an active ingredient. The alkaline earth metal salt of the resin acid is usually a compound composed of two resin acid residues and an alkaline earth metal, and is obtained by reacting a resin acid with an alkaline earth metal compound.

  The resin acids are not particularly limited, and known acids can be used. Specific examples include abietic acid, levopimaric acid, neoabietic acid, parastrinic acid, pimaric acid, isopimaric acid, sandaracopimalic acid, dehydroabietic acid, dihydroabietic acid, and tetrahydroabietic acid. In addition to rosins such as gum rosin, wood rosin, tall oil rosin and the like, which are a mixture of the resin acids, disproportionated rosin obtained by disproportionating rosins, hydrogenated rosin obtained by hydrogenating rosins, rosin Although dehydrogenated rosin obtained by dehydrogenation of acetylene can also be used, abietic acid, levopimaric acid, neoabietic acid, parastrinic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, dehydroabietic acid, dihydroabietic acid And at least one selected from the group consisting of acids and tetrahydroabietic acid.

  The alkaline earth metal compound is not particularly limited as long as it is an alkaline earth metal compound that reacts with resin acids to form a salt, and a known one can be used. Specific examples include calcium compounds, strontium compounds, barium compounds, magnesium compounds, and the like. Among these, those using a calcium compound are preferable from the viewpoints of cost, safety, and the like. Among these alkaline earth metal compounds, it is preferable to use an alkaline earth metal oxide or an alkaline earth metal hydroxide from the viewpoint of reactivity with resin acids. As these specific examples, it is preferable to use magnesium hydroxide, magnesium oxide, calcium hydroxide, calcium oxide, strontium hydroxide, strontium oxide, barium hydroxide, barium oxide, etc., and use calcium oxide and calcium hydroxide. Is particularly preferred.

  Examples of the method for synthesizing the alkaline earth metal salt of the resin acid used in the present invention include a method of reacting the resin acid in an appropriate solvent. The solvent is not particularly limited as long as it does not react with the resin acid and the alkaline earth metal compound and dissolves the resin acid, and a known solvent can be used. Specifically, for example, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 2-methoxyethanol, acetone, 2-butanone, etc. Ketones, amides such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, sulfur-containing solvents such as dimethyl sulfoxide and sulfolane, nitrogen-containing solvents such as nitromethane and nitropropane, diethyl ether, methyl t-butyl ether, di-t- Examples thereof include ether solvents having at least one ether bond such as butyl ether, dimethoxyethanol, dimethoxyethylene glycol, tetrahydrofuran, and dioxane. Among these, when an ether solvent is used as the reaction solvent, the alkaline earth metal salt of the resin acid after the reaction is obtained in a state dissolved in these solvents, and this can be used as a gelling agent as it is. Therefore, it is preferable to use these ether solvents. The presence of a small amount of water in the solvent is particularly preferable because the reaction rate between the resin acid and the alkaline earth metal compound can be increased.

  The molar ratio of the resin acid to the alkaline earth metal compound when the resin acid and the alkaline earth metal compound are reacted is not particularly limited. Generally, when an ether solvent is used, 1 mole of the resin acid is used. On the other hand, it is preferable to use 0.2 mol or more of alkaline earth metal compound. When the amount of the alkaline earth metal compound is less than 0.2 mol with respect to 1 mol of the resin acids, a large amount of unreacted resin acids may remain and the gelling performance may not be sufficiently exhibited. In addition, when the alkaline earth metal compound is used in an amount exceeding 0.5 mol with respect to 1 mol of the resin acid, an unreacted alkaline earth metal compound remains, but there is no problem in gelling performance. . If necessary, unreacted alkaline earth metal compound can be removed by filtration or centrifugation. In addition, when a solvent other than the ether solvent is used, it is usually preferable to use 0.2 mol or more of the alkaline earth metal compound with respect to 1 mol of the resin acid. In addition, when the alkaline earth metal compound is used in an amount exceeding 0.5 mol with respect to 1 mol of the resin acid, an unreacted alkaline earth metal compound remains, but there is no problem in gelling performance.

  The reaction temperature is not particularly limited, but usually the range of room temperature without requiring a special apparatus to the boiling point of the solvent used for the reaction is suitable.

  The reaction time varies depending on the reaction temperature, but is usually about 5 minutes to 24 hours. If it is less than 5 minutes, the reaction may not proceed sufficiently, and there is no particular advantage even if the reaction is carried out for 24 hours or longer.

  When a solvent other than an ether solvent is used, the alkaline earth metal salt of the resin acid is usually dispersed as a powder in the reaction solvent after completion of the reaction, and separated from the reaction solvent by filtration or centrifugation. If necessary, it can be washed with a solvent that does not dissolve the alkaline earth metal salt of the resin acid. The alkaline earth metal salt of the obtained resin acid is, for example, a solvent containing an ether bond such as diethyl ether, methyl t-butyl ether, di-t-butyl ether, dimethoxyethanol, dimethoxyethylene glycol, tetrahydrofuran, dioxane, or an alkali of a resin acid. It can be used in the present invention after being dissolved in a solvent that dissolves the earth metal salt.

  If it is difficult to synthesize an alkaline earth metal salt of a resin acid by the above method, a method generally called a metathesis method can also be adopted. The metathesis method is a method in which a resin acid is once reacted with an alkali metal hydroxide to obtain an alkali metal salt of the resin acid and then reacted with an alkaline earth metal compound.

  In the metathesis method, water-soluble organic alkaline earth metal salts and inorganic alkaline earth metal salts are usually used as the alkaline earth metal compound with which the alkali metal salt of the resin acid is reacted. Specific examples include alkaline earth metal acetates, sulfates, nitrates, chlorides and hydrates thereof.

  In the case of the metathesis method, after completion of the reaction, the product exists in a dispersed state in water as a reaction solvent, and therefore can be easily separated from water by filtration or centrifugation. It is also possible to wash the product with water.

  The alkaline earth metal salt of a resin acid obtained by the metathesis method can be used in the present invention after being dissolved in the ether solvent or a solvent capable of dissolving the alkaline earth metal salt of a resin acid.

  The siloxane compound (A) containing at least two silicon atoms (hereinafter referred to as component (A)) used for producing the gel of the present invention is not particularly limited as long as it contains at least two silicon atoms. Well-known ones can be used. Specific examples of the component (A) include cyclic siloxane compounds and chain siloxane compounds. Although it will not restrict | limit especially if it is a siloxane which has a cyclic structure as a cyclic siloxane compound, General formula (1):

(Wherein R ¹ is a lower alkyl group having 1 to 4 carbon atoms, which may be the same or different, and n represents an integer of 3 to 10). It is preferable to use a cyclic siloxane compound. Specific examples of the cyclic siloxane compound include, for example, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, pentadecamethylcycloheptasiloxane, hexadecamethylcyclooctasiloxane, hexa Examples include ethylcyclotrisiloxane, octaethylcyclotetrasiloxane, decaethylcyclopentasiloxane, and the like. Among these, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane are preferable for cosmetic use.
Further, the chain siloxane compound is not particularly limited, and a known one can be used. Specifically, the general formula (2):

(Wherein R ² is a lower alkyl group having 1 to 4 carbon atoms, which may be the same or different, and m represents an integer of 0 to 8). It is preferable. Specifically, for example, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, tetradecamethylhexasiloxane, hexamethylheptasiloxane, octadecamethyloctasiloxane, hexaethyldisiloxane, octadeca Examples thereof include ethyltrisiloxane, decaethyltetrasiloxane, dodecaethylpentasiloxane and the like. These siloxane compounds may have a branched structure.

  The siloxane gel of the present invention can be obtained by adding the siloxane compound gelling agent to the component (A). In addition, when adding the gelatinizer of this invention, gelatinization can be advanced rapidly by melt | dissolving and using the said gelatinizer in the solvent which melt | dissolves. Examples of the solvent that dissolves the gelling agent include, but are not limited to, ether solvents used when adjusting the gelling agent.

  When the siloxane compound gelling agent is used by dissolving in a solvent, the content of the alkaline earth metal salt of the resin acid contained in the siloxane compound gelling agent should be 2% by weight or more based on the solvent. It is preferable that the concentration be as high as possible. If it is less than 2% by weight, the gelation ability may not be fully exhibited. Usually, it is particularly preferably 10% by weight or more.

  The amount of the siloxane compound gelling agent dissolved in the solvent is usually appropriately determined according to the type of the siloxane compound and the type of the alkaline earth metal salt of the resin acid. Usually, the content of the alkaline earth metal salt is about 0.05 to 30% by weight, preferably 0.1 to 10% by weight, based on the siloxane compound.

The gel of the siloxane compound thus obtained contains a solvent used for preparing an alkaline earth metal salt solution. In some cases, the solvent can be removed. Examples of the solvent removal method include a method of evaporating under normal pressure or reduced pressure. For example, when tetrahydrofuran is used as the solvent used in the alkaline earth metal salt solution, it can be easily removed under normal pressure or reduced pressure.

  The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.

Example 1
3.00 g (10 mmol) of dehydroabietic acid was dissolved in a mixed solvent consisting of 14.5 g of tetrahydrofuran and 0.5 g of water, 0.37 g (5 mmol) of calcium hydroxide was added thereto, and the mixture was stirred and reacted at room temperature. After the reaction, insolubles were filtered to obtain a solution of calcium dehydroabietic acid. A portion of this was taken and dried at 105 ° C. for 2 hours, the solid content was determined from the loss on drying, and the IR spectrum of the dried solid was measured.
Solid content: 17.2% by weight
IR: 1521 cm ⁻¹ , 1415 cm ⁻¹
Tetrahydrofuran was further added to the obtained calcium salt of dehydroabietic acid to make a 15 wt% solution.
10 g of the siloxane compound shown in Table 1 was placed in a test tube, and while stirring at room temperature, the presence or absence of gel formation of a 15 wt% solution of tetrahydrofuran having the weight shown in Table 1 was observed. The results are shown in Table 1.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Example 2
The same procedure except that 3.54 g of disproportionated rosin (trade name: Longis R, manufactured by Arakawa Chemical Industries, Ltd., acid value 158) was used instead of 3.00 g (10 mmol) of dehydroabietic acid in Example 1. Operation was performed to obtain a solution of disproportionated rosin calcium salt.
Solid content: 19.3% by weight
IR: 1525 cm ⁻¹ , 1418 cm ⁻¹
Tetrahydrofuran was further added to the obtained solution to make 15% by weight.
10 g of the object to be gelled was placed in a test tube, and while stirring at room temperature, a 15 wt% solution of tetrahydrofuran having the weight shown in Table 2 was added, and the presence or absence of gel formation was observed. The results are shown in Table 2.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Example 3
The same operation was performed except that 3.27 g of tall oil rosin (trade name: TOR35-240, manufactured by Arizona Chemical Co., acid value 171) was used instead of 3.00 g (10 mmol) of dehydroabietic acid of Example 1. A solution of tall oil rosin calcium salt was obtained.
Solid content: 18.6% by weight
IR: 1524 cm ⁻¹ , 1417 cm ⁻¹
A tetrahydrofuran solution was further added to the obtained solution to make 15% by weight.
10 g of the object to be gelled was placed in a test tube, and while stirring at room temperature, a 15 wt% solution of tetrahydrofuran having the weight shown in Table 3 was added, and the presence or absence of gel formation was observed. The results are shown in Table 3.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Example 4
A solution of strontium dehydroabietic acid salt was obtained in the same manner as in Example 1 except that 1.33 g (5 mmol) of strontium hydroxide octahydrate was used instead of 0.37 g (5 mmol) of calcium hydroxide. It was.
Solid content: 17.6% by weight
IR: 1525 cm ⁻¹ , 1405 cm ⁻¹
A tetrahydrofuran solution was further added to the obtained solution to make 15% by weight.
10 g of the gelation target was placed in a test tube, and while stirring at room temperature, a 15 wt% solution of tetrahydrofuran having the weight shown in Table 4 was added, and the presence or absence of gel formation was observed. The results are shown in Table 4.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Example 5
After adding 3.7 g (0.05 mol) of calcium hydroxide to 200 g of a mixture of isopropanol (88 wt%) and water (12 wt%) (hereinafter abbreviated as 88% IPA) and stirring and dispersing, A solution prepared by dissolving 33 g of averaged rosin (trade name: KR-614, manufactured by Arakawa Chemical Industries, Ltd., acid value 173) in 200 g of 88% IPA was added dropwise over 30 minutes under reflux. The mixture was further stirred for 4 hours under reflux, cooled, filtered, and washed with 100 g of 88% IPA. The obtained filtrate was taken out and dried under reduced pressure at 80 ° C. for 4 hours to obtain 28.8 g of white powder.
Melting point: not melted to 300 ° C. IR: 1521 cm ⁻¹ , 1414 cm ⁻¹
This was dissolved in tetrahydrofuran to prepare a 15% by weight solution.
10 g of the object to be gelled was placed in a test tube, and while stirring at room temperature, a 15% by weight solution of a tetrahydrofuran solution having the weight shown in Table 5 was added and the presence or absence of gel formation was observed. The results are shown in Table 5.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Example 6
The same operation was carried out except that barium hydroxide octahydrate was changed to 13.3 g (0.05 mol) instead of calcium hydroxide in Example 6 to obtain 25.1 g of white powder.
Melting point: not melted to 300 ° C. IR: 1536 cm ⁻¹ , 1396 cm ⁻¹
Tetrahydrofuran was added to this to prepare a 15 wt% dispersion.
10 g of the gelation target was placed in a test tube, and while stirring at room temperature, a 15 wt% dispersion of a tetrahydrofuran solution having the weight shown in Table 6 was added, and the presence or absence of gel formation was observed. The results are shown in Table 6.

Ｇ：ゲル化 Ｐ：一部ゲル化

G: Gelation P: Partial gelation

Claims (8)

A gelling agent for a siloxane compound, comprising an alkaline earth metal salt of a resin acid. The resin acid is at least one selected from the group consisting of abietic acid, levopimaric acid, neoabietic acid, parastrinic acid, pimaric acid, isopimaric acid, sandaracopimalic acid, dehydroabietic acid, dihydroabietic acid and tetrahydroabietic acid The gelling agent for siloxane compounds according to claim 1. The gelling agent for siloxane compounds according to claim 1 or 2, wherein the alkaline earth metal is at least one selected from the group consisting of calcium, strontium, barium and magnesium. The gelling agent for a siloxane compound according to any one of claims 1 to 3, wherein the alkaline earth metal is calcium. A gel obtained by gelling a siloxane compound (A) containing at least two silicon atoms with the gelling agent for a siloxane compound according to any one of claims 1 to 4. A siloxane compound (A) containing at least two silicon atoms is represented by the general formula (1):

(In the formula, R ¹ is a lower alkyl group having 1 to 4 carbon atoms, which may be the same or different, and n represents an integer of 3 to 10).
A cyclic siloxane compound represented by the general formula (2):

(In the formula, R ² is a lower alkyl group having 1 to 4 carbon atoms, which may be the same or different, and m represents an integer of 0 to 8.)
The gel according to claim 5, which is a siloxane compound represented by the formula: A method for producing a gel, comprising adding the gelling agent for a siloxane compound according to any one of claims 1 to 4 to a siloxane compound (A) containing at least two silicon atoms. The method for producing a gel according to claim 7, wherein a solvent for dissolving the gelling agent for a siloxane compound according to any one of claims 1 to 4 is added.