JPH11293110A - Silicone emulsion, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silicone emulsion, narrow in particles size distribution and excellent in stability, even with a small quantity of surfactant, and to provide a method for producing it. SOLUTION: This silicone emulsion is obtained by emulsifying a silicone oil in water in the presence of an alkyl ether of polyethylene oxide, wherein the alkyl group having a carbon number of 13 accounts for at least 10 wt.% of the alkyl groups in the alkyl ether. In this method for producing a silicone emulsion by emulsifying silicone oil in water in the presence of an alkyl ether of polyethylene oxide, the alkyl group having a carbon number of 13 accounts for at least 10 wt.% of the alkyl groups in the alkyl ether.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a silicone emulsion and a method for producing the same, and more particularly, to a silicone emulsion having a narrow particle size distribution and excellent stability even with a small amount of a surfactant, and a method for producing the same.

[0002]

2. Description of the Related Art A method of producing a silicone emulsion by emulsifying silicone oil in water with a surfactant is well known. In this silicone emulsion,
As typified by cosmetics applications, it is preferable that the amount of the surfactant added is small and that the surfactant is a nonionic surfactant.

However, nonionic surfactants do not have sufficient emulsifying ability, and the resulting silicone emulsions have a wide particle size distribution and poor stability, so they must be added in large amounts. There was a problem.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have intensively studied the above-mentioned problems, and as a result, have reached the present invention. That is, an object of the present invention is to provide a silicone emulsion having a narrow particle size distribution and excellent stability even with a small amount of a surfactant, and a method for producing the same.

[0005]

The silicone emulsion of the present invention is a silicone emulsion obtained by emulsifying a silicone oil in water with an alkyl ether of polyethylene oxide, wherein at least 10% by weight of the alkyl group in the alkyl ether is contained. It is an alkyl group having 13 carbon atoms. The method for producing a silicone emulsion of the present invention is a method for producing a silicone emulsion by emulsifying a silicone oil in water with an alkyl ether of polyethylene oxide, wherein at least 10% by weight of the alkyl groups in the alkyl ether is carbon. It is an alkyl group represented by Formula 13.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the silicone emulsion of the present invention will be described in detail. Silicone emulsions obtained by emulsifying silicone oil in water with an alkyl ether of polyethylene oxide are well known. However, at least 10% by weight of the alkyl group in the alkyl ether is an alkyl ether of polyethylene oxide having 13 carbon atoms. A silicone emulsion emulsified in water is not known. In the silicone emulsion of the present invention, examples of the silicone oil include non-curable and curable silicone oils.
The viscosity at 5 ° C is 1 to 50,000,000 mP
It is preferably within the range of a · s, particularly 5 to 1.00.
It is preferable that it is within the range of 0.000 mPa · s. This means that the viscosity at 25 ° C. is less than 1 mPa · s, or the viscosity at 25 ° C. is 50,000,000 mPa · s.
This is because it is difficult to emulsify a substance exceeding the above.

[0007] The non-curable silicone oil is not particularly limited, and its molecular structure is exemplified by a straight chain, a partially branched straight chain, a cyclic chain, and a branched chain chain. Is preferred. Examples of such non-curable silicone oils include polydimethylsiloxane having a molecular chain at both ends of a trimethylsiloxy group, a dimethylsiloxane / methylphenylsiloxane copolymer having a molecular chain at both ends of a trimethylsiloxy group, and a molecular chain having both ends of a molecular chain at a trimethylsiloxy group. Nonfunctional silicone oils such as dimethylsiloxane / methyl (3,3,3-trifluoropropyl) siloxane copolymer, silicone oils having a silicon-bonded hydrolyzable group, silicone oils having a silanol group, Silicone oil having a saturated group, silicone oil having a long-chain alkyl group, silicone oil having a polyether group, silicone oil having an amide group, silicone oil having a carboxylic acid group,
Examples thereof include a silicone oil having an amino group, a silicone oil having a mercapto group, and a silicone oil having an epoxy group.

On the other hand, examples of the curable silicone oil include a silicone oil that is cured by itself and a silicone oil that is cured by adding a curing catalyst or a crosslinking agent. The curing mechanism includes, for example, a condensation reaction, a hydrosilylation reaction, a radical reaction with an organic peroxide, and a radical reaction with ultraviolet rays. Since there are no by-products due to the curing reaction and high reactivity, hydrosilyl is particularly preferred. The reaction is preferably a chemical reaction. This condensation reaction-curable silicone oil includes at least two silicone oils per molecule.
An organopolysiloxane having a hydrolyzable group such as a hydroxyl group, an alkoxy group, an oxime group, an acetoxy group, an aminoxy group, or a hydrogen atom bonded to a silicon atom,
Furthermore, a silane-based or siloxane-based crosslinking agent having a hydroxyl group, an alkoxy group, an oxime group, an acetoxy group, an aminoxy group, or a hydrogen atom bonded to at least two silicon atoms in one molecule, and an organic tin An oily silicone composition obtained by mixing a condensation reaction catalyst such as a compound and an organic titanium compound is exemplified. Examples of the hydrosilylation-curable silicone oil include organopolysiloxanes having at least two alkenyl groups in one molecule and organopolysiloxanes having at least two hydrogen atoms bonded to silicon atoms in one molecule. And an oily silicone composition obtained by mixing a hydrosilylation reaction catalyst with the silicone composition.

In the silicone emulsion of the present invention, the average particle size of the silicone oil dispersed in water is preferably in the range of 0.1 to 500 μm, particularly preferably in the range of 0.5 to 50 μm. It is preferred that

The silicone oil emulsion of the present invention is characterized in that as the alkyl ether of polyethylene oxide, an alkyl ether in which at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms is used. According to such an alkyl ether, even if it is added in a small amount, the particle size distribution of the obtained silicone emulsion is narrow and the stability is excellent. The alkyl group in this alkyl ether has 13 carbon atoms.
At least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms, and at least 10% by weight of the alkyl group in the alkyl group ether is an alkyl group having 13 carbon atoms. It is particularly preferred that at least 10% by weight is an alkyl group having 12 carbon atoms. Further, the other alkyl group in the alkyl ether is preferably an alkyl group having 14 or more carbon atoms. In the silicone emulsion of the present invention, the alkyl group in the alkyl ether is preferably a secondary alkyl group. The HLB value of such an alkyl ether of polyethylene oxide is preferably in the range of 10 to 16.

As such alkyl ethers of polyethylene oxide, a secondary tridecyl ether to which ethylene oxide is added in an amount of 2 to 30 mol per molecule, and a mixture of this tridecyl ether and ethylene oxide in an amount of 2 to 30 mol per molecule are added. Examples thereof include a mixture with a secondary dodecyl ether, and a mixture of these mixtures with a secondary tetradecyl ether to which ethylene oxide is added in an amount of 2 to 30 mol per molecule. In particular, ethylene oxide is added in an amount of 5 to 13 mol per molecule. Secondary tridecyl ether, a mixture of the tridecyl ether and a secondary dodecyl ether to which ethylene oxide is added in an amount of 5 to 13 moles per molecule, and a mixture of this mixture and 5 to 13 moles of ethylene oxide in which ethylene oxide is added per molecule. With tetra-tetradecyl ether There it is preferable.

In the silicone emulsion of the present invention, the addition amount of the alkyl ether of the polyethylene oxide is 0.1 to 100 parts by weight of the silicone oil.
It is preferably in the range of 01 to 50 parts by weight, and particularly preferably in the range of 0.1 to 10 parts by weight. The amount of water added is preferably in the range of 5 to 2,000 parts by weight, particularly preferably in the range of 10 to 1,000 parts by weight, based on 100 parts by weight of the silicone oil.

The silicone emulsion of the present invention can be used as a release agent, a fiber treatment agent, a cosmetic, a detergent, a lubricant, a water repellent, a paint, and the like. When a curable silicone oil is used, an aqueous suspension of the cured silicone powder can be obtained by curing the silicone in the obtained silicone emulsion. Then, by further removing moisture from the suspension, a cured silicone powder can be obtained. Examples of the shape of the cured silicone powder thus obtained include a spherical shape, a flat shape, and an irregular shape, and a spherical shape is preferable. Examples of the properties of the cured silicone powder include rubber and gel, preferably rubber.

Next, the method for producing the silicone emulsion of the present invention will be described in detail. A method for producing a silicone emulsion by emulsifying silicone oil in water with an alkyl ether of polyethylene oxide is well known, and examples of the emulsifier used in this method include a homomixer, a homogenizer, and a colloid mill. In the production method of the present invention, examples of the silicone oil include non-curable and curable silicone oils.
mPa · s, preferably 5 to 1,0
It is preferably within the range of 00,000 mPa · s. This means that the viscosity at 25 ° C. is less than 1 mPa · s, or the viscosity at 25 ° C. is 50,000,000 mPa · s.
This is because it is difficult to emulsify a substance exceeding the above.

The non-curable silicone oil is not particularly limited, and its molecular structure is exemplified by a straight chain, a partially branched straight chain, a cyclic chain, and a branched chain chain. Is preferred. Examples of such non-curable silicone oils include polydimethylsiloxane having a molecular chain at both ends of a trimethylsiloxy group, a dimethylsiloxane / methylphenylsiloxane copolymer having a molecular chain at both ends of a trimethylsiloxy group, and a molecular chain having both ends of a molecular chain at a trimethylsiloxy group. Nonfunctional silicone oils such as dimethylsiloxane / methyl (3,3,3-trifluoropropyl) siloxane copolymer, silicone oils having a silicon-bonded hydrolyzable group, silicone oils having a silanol group, Silicone oil having a saturated group, silicone oil having a long-chain alkyl group, silicone oil having a polyether group, silicone oil having an amide group, silicone oil having a carboxylic acid group,
Examples thereof include a silicone oil having an amino group, a silicone oil having a mercapto group, and a silicone oil having an epoxy group.

On the other hand, examples of the curable silicone oil include a silicone oil that cures by itself and a silicone oil that cures by adding a curing catalyst or a crosslinking agent. The curing mechanism includes, for example, a condensation reaction, a hydrosilylation reaction, a radical reaction with an organic peroxide, and a radical reaction with ultraviolet rays. Since there are no by-products due to the curing reaction and high reactivity, hydrosilyl is particularly preferred. The reaction is preferably a chemical reaction. This condensation reaction-curable silicone oil includes at least two silicone oils per molecule.
An organopolysiloxane having a hydrolyzable group such as a hydroxyl group, an alkoxy group, an oxime group, an acetoxy group, an aminoxy group, or a hydrogen atom bonded to a silicon atom,
Furthermore, a silane-based or siloxane-based crosslinking agent having a hydroxyl group, an alkoxy group, an oxime group, an acetoxy group, an aminoxy group, or a hydrogen atom bonded to at least two silicon atoms in one molecule, and an organic tin An oily silicone composition obtained by mixing a condensation reaction catalyst such as a compound and an organic titanium compound is exemplified. The hydrosilylation reaction-curable silicone oil comprises an organopolysiloxane having at least two alkenyl groups in one molecule and an organopolysiloxane having at least two silicon-bonded hydrogen atoms in one molecule. Oily silicone composition,
Furthermore, an oily silicone composition obtained by mixing a hydrosilylation reaction catalyst with the silicone composition is exemplified.

In the production method of the present invention, the amount of the alkyl ether of the polyethylene oxide to be added is preferably in the range of 0.01 to 50 parts by weight, more preferably 0.1 to 50 parts by weight, per 100 parts by weight of the silicone oil. It is preferably in the range of 10 to 10 parts by weight. The amount of water to be added is 5 to 2.0 with respect to 100 parts by weight of the silicone oil.
00 parts by weight, particularly 10 parts by weight.
It is preferred that the amount be in the range of ~ 1,000 parts by weight.

In the production method of the present invention, the alkyl ether of polyethylene oxide is characterized in that at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms. According to such an alkyl ether, even with a small amount of addition, a silicone emulsion having a narrow particle size distribution and excellent stability can be produced. The alkyl group in this alkyl ether has 13 carbon atoms.
At least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms, and at least 10% by weight of the alkyl group in the alkyl ether is at least 10% by weight. It is particularly preferred that 10% by weight is an alkyl group having 12 carbon atoms. Further, the other alkyl group in the alkyl ether is preferably an alkyl group having 14 or more carbon atoms. In the present method, the alkyl group in the alkyl ether is preferably a secondary alkyl group. The HLB value of such an alkyl ether of polyethylene oxide is preferably in the range of 10 to 16.

Examples of the alkyl ether of polyethylene oxide include a secondary tridecyl ether to which ethylene oxide is added in an amount of 2 to 30 mol per molecule, and a mixture of this tridecyl ether and ethylene oxide in an amount of 2 to 30 mol per molecule. Examples thereof include a mixture with a secondary dodecyl ether, and a mixture of these mixtures with a secondary tetradecyl ether to which ethylene oxide is added in an amount of 2 to 30 mol per molecule. In particular, ethylene oxide is added in an amount of 5 to 13 mol per molecule. Secondary tridecyl ether, a mixture of the tridecyl ether and a secondary dodecyl ether to which ethylene oxide is added in an amount of 5 to 13 moles per molecule, and a mixture of this mixture and 5 to 13 moles of ethylene oxide in which ethylene oxide is added per molecule. With tetra-tetradecyl ether There it is preferable.

The average particle size of the silicone in the silicone emulsion thus obtained is 0.1 to 0.1.
It is preferably within the range of 500 μm, in particular,
It is preferable that the thickness be in the range of 0.5 to 50 μm.

[0021]

EXAMPLES The silicone emulsion of the present invention and the method for producing the same will be described in detail with reference to examples. In addition, the viscosity in an Example is a value measured at 25 degreeC. Also,
The particle size distribution of silicone in the silicone emulsion is
Laser diffraction particle size distribution analyzer (LA-
500) and its median diameter (50 of the cumulative distribution).
%, Average particle diameter), the content (volume%) of the silicone having a particle diameter of 10.0 μm or less, and the particle diameter of the silicone which accumulates to 90 vol%.

Example 1 Mixture of 100 parts by weight of polydimethylsiloxane having a viscosity of 400 mPa · s and capped with trimethylsiloxy groups at both ends of the molecular chain, and secondary dodecyl ether and secondary tridecyl ether of ethylene oxide (addition of 7 mol)
(43% by weight of dodecyl group, 57% by weight of tridecyl group, H
LB = 12.8) 3 parts by weight and 30 parts by weight of water were preliminarily mixed and then emulsified by a colloid mill to prepare a silicone emulsion. Table 1 shows the particle size distribution of silicone in the silicone emulsion. The silicone emulsion was uniform after one month.

COMPARATIVE EXAMPLE 1 100 parts by weight of polydimethylsiloxane having a viscosity of 400 mPa · s and capped with trimethylsiloxy groups at both ends of the molecular chain, and a secondary dodecyl ether of ethylene oxide (addition of 4.2 mol) (Tarditol manufactured by Union Carbide Co., USA) TMN-6, HLB = 11.5) 3 parts by weight,
After water and 30 parts by weight of water were premixed, the mixture was emulsified by a colloid mill to prepare a silicone emulsion. Table 1 shows the particle size distribution of silicone in the silicone emulsion. One month later, silicone oil spots were observed on the surface of this silicone emulsion.

Example 2 A mixture of a secondary dodecyl ether and a secondary tridecyl ether of ethylene oxide (addition of 5 mol) with 100 parts by weight of polydimethylsiloxane having a viscosity of 400 mPa · s and capped with trimethylsiloxy groups at both ends of the molecular chain and ethylene Mixture of a mixture of secondary dodecyl ether of oxide (12 mole addition) and secondary tridecyl ether (43% by weight of dodecyl group, 57% by weight of tridecyl group, HLB
= 10.5) 3 parts by weight and 30 parts by weight of water were premixed and then emulsified by a colloid mill to prepare a silicone emulsion. Table 1 shows the particle size distribution of silicone in the silicone emulsion. The silicone emulsion was uniform after one month.

Example 3 96 parts by weight of polydimethylsiloxane having a viscosity of 400 mPa · s at both ends of a dimethylvinylsiloxy group and 4 parts by weight of polymethylhydrodienesiloxane having a viscosity of 20 mPa · s and having both ends of a trimethylsiloxy group. 6 parts by weight of a trimethylsiloxy-group-blocked polydimethylsiloxane having a molecular weight of 20 mPa · s and an isopropyl alcohol solution of chloroplatinic acid (the weight of platinum metal relative to the above-mentioned polydimethylsiloxane having a dimethylvinylsiloxy group-blocked at both ends is a weight unit) To give a silicone rubber composition having a viscosity of about 350 mPa · s. Then, the composition is mixed with 3% by weight of a secondary dodecyl ether of ethylene oxide (7 mole addition) and a secondary dodecyl ether. Mixture of tridecyl ethers (43% by weight of dodecyl group, 57% by weight of tridecyl group) After the aqueous solution 53 parts by weight of HLB = 12.8) were preliminarily mixed to prepare an emulsion of a silicone rubber composition which is emulsified by a homogenizer.

Next, 50 parts by weight of pure water was mixed with the emulsion and left at room temperature for 1 day to cure the silicone rubber composition, thereby preparing an aqueous suspension of silicone rubber powder. This suspension is 3
The silicone rubber powder was obtained by drying with a hot air drier at 00 ° C.

Comparative Example 2 In Example 3, ethylene oxide (9.5) was used instead of a mixture of secondary dodecyl ether and secondary tridecyl ether of ethylene oxide (7 mol addition) (HLB = 12.8). An emulsion of the silicone rubber composition was prepared in the same manner as in Example 3 except that nonylphenyl ether (HLB = 13.1) was used. Using this emulsion, a silicone rubber powder was obtained in the same manner as in Example 3.

[0028]

[Table 1]

[0029]

The silicone emulsion of the present invention is characterized by having a narrow particle size distribution and excellent stability even with a small amount of a surfactant. The feature is that it can be manufactured efficiently.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Takashi Tachibana 2-2 Chikusa Beach, Ichihara City, Chiba Prefecture Toray Dow Corning Silicone Co., Ltd.

Claims (6)

[Claims] 1. A silicone emulsion obtained by emulsifying silicone oil in water with an alkyl ether of polyethylene oxide, wherein at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms. Silicone emulsion. 2. The alkyl group in the alkyl ether of polyethylene oxide comprises at least an alkyl group having 13 carbon atoms and an alkyl group having 12 carbon atoms, and at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms. The silicone emulsion according to claim 1, wherein the alkyl group is a group, and at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 12 carbon atoms. 3. The silicone emulsion according to claim 1, wherein the alkyl group in the alkyl ether of the polyethylene oxide is a secondary alkyl group. 4. A method for producing a silicone emulsion by emulsifying silicone oil in water with an alkyl ether of polyethylene oxide, wherein at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms. A method for producing a silicone emulsion. 5. An alkyl group in an alkyl ether of polyethylene oxide comprising at least an alkyl group having 13 carbon atoms and an alkyl group having 12 carbon atoms, wherein at least 10% by weight of the alkyl group in the alkyl ether is an alkyl group having 13 carbon atoms. 5. The method for producing a silicone emulsion according to claim 4, wherein the alkyl group in the alkyl ether is an alkyl group having 12 carbon atoms. 6. The method for producing a silicone emulsion according to claim 4, wherein the alkyl group in the alkyl ether of polyethylene oxide is a secondary alkyl group.