JP2002188055A - Silicon emulsion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicon emulsion having small mean particle diameter even by using a relatively small amount of a surfactant and excellent in a short term and long term stability. SOLUTION: This silicon emulsion is obtained by using (A) a polyoxyethylene alkyl ether having 6-11 alkyl chain length and (B) a polyoxyethylene alkyl ether having 16-20 alkyl chain length simultaneously as an emulsifying agent, in emulsifying the silicon oil in water by using an emulsifying agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicone emulsion, and more particularly to a silicone emulsion having a small average particle size and excellent stability by using a specific surfactant.

[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,
It is preferable that the addition amount of the surfactant is small and the surfactant is a nonionic type, as represented by the release application and the coating agent application. However, nonionic surfactants do not have sufficient emulsifying ability, and the particle size distribution of the obtained silicone emulsion is widened, or the stability is deteriorated. there were.

In order to solve this problem, Japanese Patent Application Laid-Open No.
No. 293110 proposes to use a surfactant mainly composed of polyoxyethylene alkyl ether having an alkyl chain length of 13. However, according to the follow-up test of the present inventors, although the method provides a silicone emulsion having a narrow particle size distribution and excellent stability to some extent, its effect is insufficient, and its long-term stability, particularly when diluted with hard water, is obtained. However, there is a problem in that the stability at the time of forming is poor, and it is difficult to obtain one having a small particle size.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have solved the above-mentioned problems, and have developed a silicone emulsion having a small average particle size and excellent short-term and long-term stability even with a relatively small amount of a surfactant. As a result of intensive studies for the purpose of providing, it was found that the combined use of a specific surfactant was extremely effective, and the present invention was completed.

[0005]

That is, the present invention provides a silicone emulsion obtained by emulsifying a silicone oil in water using an emulsifier, wherein (A) a polyoxyethylene having an alkyl chain length of 6 to 11 is used as the emulsifier. A silicone emulsion comprising a combination of an alkyl ether and (B) a polyoxyethylene alkyl ether having an alkyl chain length of 16 to 20.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
First, in the silicone emulsion of the present invention, examples of the silicone oil include non-curable and curable silicone oils.
It is preferably within the range of 0,000,000 mPas, particularly preferably within the range of 5 to 1,000,000 mPas, and more preferably 100 to 5,000 mPas.
Pa · s. This is because the viscosity at 25 ° C is 1 mPa · s
Less than 50, or a viscosity at 25 ° C. of 50,
This is because it is difficult to emulsify a substance exceeding 1,000,000 mPa · s.

[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 trimethylsiloxy groups at both ends of a molecular chain. 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 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 silicone oils obtained by mixing a hydrosilylation reaction catalyst with the silicone.

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 0.01 to 200 μm, particularly preferably in the range of 0.1 to 20 μm. It is preferred that

A feature of the present invention is that when a silicone oil is emulsified in water using an emulsifier to produce a silicone emulsion, (A) an alkyl chain length of 6 to 6 is used as an emulsifier.
An object of the present invention is to use a combination of a polyoxyethylene alkyl ether of No. 11 and a polyoxyethylene alkyl ether having a (B) alkyl chain length of 16 to 20.

By using two kinds of polyoxyethylene alkyl ethers having different alkyl chain lengths in combination, even if a relatively small amount is added, the obtained silicone emulsion has a narrow particle size distribution and excellent stability. .

Here, (A) Examples of the alkyl group in the polyoxyethylene alkyl ether having an alkyl chain length of 6 to 11 include a hexyl, heptyl, octyl, nonyl, decyl and undecyl group, particularly a decyl group having 10 carbon atoms. Is preferred. It may also have branches.

On the other hand, examples of the alkyl group in the polyoxyethylene alkyl ether (B) having an alkyl chain length of 16 to 20 include cetyl (hexadecyl), heptadecyl, octadecyl, nonadecyl and eicosyl groups, with cetyl being particularly preferred. It may also have branches.

The ratio of the components (A) and (B) used is (A) 1
(B) is preferably from 1 to 10,000 parts by weight to 100 parts by weight, particularly preferably (B) from 10 to 100 parts by weight based on 100 parts by weight of (A).
1000 parts by weight. Outside this range, the desired effects of the present invention cannot be obtained.

The number of moles of ethylene oxide added to the polyoxyethylene alkyl ether of the components (A) and (B) is not particularly limited, but is preferably about 2 to 30 moles. The HLB values of the components (A) and (B) are not particularly limited, but are preferably in the range of 10 to 16.

In the silicone emulsion of the present invention, the polyoxyethylene alkyl ether is added in an amount of 0.1 to 100 parts by weight, based on 100 parts by weight of the silicone oil, as a total of the components (A) and (B). It is preferably in the range, and particularly preferably in the range of 1 to 50 parts by weight. More preferably, it is in the range of 5 to 20 parts by weight.

The amount of water to be added depends on the amount of silicone oil 1
The amount is preferably in the range of 5 to 2,000 parts by weight, particularly preferably in the range of 20 to 1,000 parts by weight, based on 00 parts by weight.

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.

Next, the silicone emulsion of the present invention can be produced by a conventionally known method. Examples of the emulsifier used in this method include a homomixer, a homogenizer, and a colloid mill.

[0020]

EXAMPLES The silicone emulsion of the present invention will be described in more detail with reference to examples. In addition, the part in an Example shows a weight part, and a viscosity is the value measured at 25 degreeC. The particle size of the silicone in the silicone emulsion can be measured with a laser diffraction particle size distribution analyzer (LS, manufactured by Beckman Coulter).
-230), and the median diameter (particle diameter corresponding to 50% of the cumulative distribution: average particle diameter) was measured.
A particle size of ~ 90% width was determined. Example 1 Alkyl-modified silicone oil having a viscosity of 700 mPa · s 10
After uniformly mixing 0 parts, 9 parts of polyoxyethylene decyl ether (addition of 5 moles of ethylene oxide) and 2.5 parts of polyoxyethylene cetyl ether (addition of 25 moles of ethylene oxide), 12 parts of water were gradually added. Premixed.

After emulsifying this in a colloid mill, water (80
To obtain a silicone emulsion. Example 2 Alkyl-modified silicone oil 10 having a viscosity of 700 mPa · s
0 parts, polyoxyethylene decyl ether (addition of 3 moles of ethylene oxide) 7.7 parts, polyoxyethylene oleyl ether (addition of 30 moles of ethylene oxide)
After uniformly mixing 3.8 parts, 12 parts of water was gradually added and preliminarily mixed.

After emulsifying this in a colloid mill, water (80
To obtain a silicone emulsion. Example 3 100 parts of polydimethylsiloxane capped with trimethylsiloxy groups at both ends of molecular chain having a viscosity of 400 mPa · s, polyoxyethylene decyl ether (addition of 5 mol of ethylene oxide)
After uniformly mixing 10 parts and 3 parts of polyoxyethylene cetyl ether (addition of 25 moles of ethylene oxide), 11 parts of water was gradually added and premixed.

After emulsifying this in a colloid mill, water (80
To obtain a silicone emulsion. Comparative Example 1 Alkyl-modified silicone oil 10 having a viscosity of 700 mPa · s
After uniformly mixing 0 parts, 7 parts of polyoxyethylene cetyl ether (addition of 5 mol of ethylene oxide) and 4.5 parts of polyoxyethylene cetyl ether (addition of 40 mol of ethylene oxide), 12 parts of water were gradually added. Premixed.

After emulsifying this in a colloid mill, water (80
To obtain a silicone emulsion. Comparative Example 2 100 parts of polydimethylsiloxane capped with trimethylsiloxy groups at both ends of molecular chain having a viscosity of 400 mPa · s, 1.3 parts of polyoxyethylene secondary dodecyl ether (addition of 7 moles of ethylene oxide), and polyoxyethylene secondary tridecyl ether ( After uniformly mixing 1.7 parts of ethylene oxide (9 mol addition), 30 parts of water was gradually added and preliminarily mixed.

This was emulsified in a colloid mill to obtain a silicone emulsion.

Table 1 shows the average particle size of the silicone emulsions of the above Examples and Comparative Examples.

Further, the stock solution of the silicone emulsion was
Table 2 shows the results of the stability evaluation when stored at 5 ° C. and 50 ° C. for a long time, and Table 3 shows the results of the storage stability evaluation of the active ingredient diluted to 6% with city water. Table 4 shows the results of storage stability evaluation of the components diluted to 6%.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

[Table 4]

[0032]

The silicone emulsion of the present invention is characterized by having a small average particle size and excellent stability by using a specific surfactant, and is suitably used in various fields.

Claims (5)

[Claims] 1. A silicone emulsion obtained by emulsifying silicone oil in water using an emulsifier, wherein (A) a polyoxyethylene alkyl ether having an alkyl chain length of 6 to 11 and (B) an alkyl chain length Is 16-2
A silicone emulsion, which is used in combination with a polyoxyethylene alkyl ether of 0. 2. A polyoxyethylene alkyl ether having (A) an alkyl chain length of 6 to 11 and (B) an alkyl chain length of 16
2. The silicone emulsion according to claim 1, wherein the ratio of the polyoxyethylene alkyl ether to the polyoxyethylene alkyl ether is from 1 to 10,000 parts by weight per 100 parts by weight of (A). 3. The silicone emulsion according to claim 1, wherein the silicone oil is a linear, cyclic or branched silicone or a modified silicone. 4. The silicone emulsion according to claim 1, wherein the emulsifier is used in a total amount of 0.1 to 100 parts by weight based on 100 parts by weight of the silicone oil. 5. The silicone emulsion according to claim 1, wherein the silicone emulsion has an average particle size of 0.01 to 200 μm.