JP2017214503A - Method for producing polymethylsilsesquioxane particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing polymethylsilsesquioxane particles that can achieve both of uniform particle size and stable dispersion in organic solvent.SOLUTION: A method for producing polymethylsilsesquioxane particles has the step of mixing a hydrolysis liquid (a) that contains a hydrolysate of a compound represented by formula (1), water, and an anionic surfactant (s1) [in formula (1): CHSi(OR), R is a C1-C6 alkyl group] with a deposition liquid (b) that contains water, a base catalyst and an anionic surfactant (s2).SELECTED DRAWING: None

Description

  The present invention relates to a method for producing polymethylsilsesquioxane particles. More specifically, the present invention relates to a method for producing polymethylsilsesquioxane particles having high production efficiency and uniform particle diameter.

  Various methods have been known as methods for obtaining spherical polymethylsilsesquioxane fine particles. In recent years, not only micron-sized polymethylsilsesquioxane fine particles but also submicron or nano-sized fine particles have been known. Also disclosed is a method for producing polymethylsilsesquioxane fine particles having various particle sizes.

  For example, in Patent Document 1, after hydrolyzing methyltrialkoxysilane in an aqueous acid solution adjusted to an electrical conductivity of 0.5 to 200 mS / m by adding an inorganic acid such as hydrochloric acid, the aqueous solution is converted into an alkaline aqueous solution. A method for producing polymethylsilsesquioxane fine particles having a particle diameter of 0.1 to 1 μm by dropping is described.

  Further, Patent Document 2 discloses a step of hydrolyzing / partial condensation of organotrialkoxysilane in an acid aqueous solution, and allowing the hydrolysis / partial condensate to stand for separation into an upper layer and a lower layer, and taking out the lower layer portion to remove an organic solvent. And a method for producing polyorganosilsesquioxane fine particles having a particle diameter of 1 μm or less, including a step of mixing with an organic solvent mixed hydrolysis / partial condensate with an alkali.

  In Patent Document 3, an aqueous dispersion of polymethylsilsesquioxane fine particles is prepared by mixing a dispersion stabilizer, a base catalyst, and methyltrimethoxysilane in the presence of an aqueous solvent and hydrolyzing and condensing methyltrimethoxysilane. A method for producing a polymethylsilsesquioxane fine particle organic solvent dispersion in which the pH of this aqueous dispersion is adjusted to 2 to 9 and substituted with an organic solvent after production is described.

  Further, Patent Document 4 discloses a method for producing polymethylsilsesquioxane fine particles by simultaneously performing a hydrolysis reaction and a condensation reaction of an alkoxysilane such as methyltrimethoxysilane in the presence of a specific acid catalyst. Yes.

JP 2000-178357 A JP 2008-208158 A International Publication No. 2006/70846 JP 2006-89514 A

  However, in these conventional production methods, aggregates of polymethylsilsesquioxane fine particles obtained are generated in the production process, and clogging is likely to occur in the filtration process after the production of the particles, resulting in a decrease in productivity. There is a problem, and the dispersion stability of the polymethylsilsesquioxane fine particles in an organic solvent may not be sufficient. The present invention has been made in view of the above circumstances, and provides a method for producing polymethylsilsesquioxane particles with high productivity that can achieve both uniformity in particle diameter and dispersion stability in an organic solvent. Is an issue.

  As a result of studies to solve the above-mentioned problems, the present inventors have found that a hydrolyzed solution containing a precursor of polymethylsilsesquioxane particles and an anionic surfactant, water, and an anionic surfactant It has been found that polymethylsilsesquioxane particles having a uniform particle size, few aggregates, and good dispersion stability in an organic solvent can be produced by mixing with a precipitation solution containing benzene. That is, the present invention includes the following inventions.

[1] A hydrolyzate (a) containing a hydrolyzate of the compound represented by formula (1), water and an anionic surfactant (s1);
CH ₃ Si (OR) ₃ (1)
[In formula (1), R represents a C1-C6 alkyl group. ]
The manufacturing method of the polymethylsilsesquioxane particle | grains including the process of mixing the precipitation liquid (b) containing water, a base catalyst, and an anionic surfactant (s2).
[2] The production method according to [1], wherein the hydrolysis liquid (a) further contains an acid catalyst.
[3] The mass ratio of the compound represented by the formula (1) and the anionic surfactant (s1) (anionic surfactant (s1) / the compound represented by the formula (1)) is 0. The production method according to [1] or [2], which is from 0005 to 0.05.
[4] The production method according to any one of [1] to [3], wherein the hydrolyzate (a) has a pH of 2.0 or more and 5.5 or less.
[5] The production method according to any one of [1] to [4], wherein the pH of the precipitation liquid (b) is 8.0 or more and 13.0 or less.
[6] The production method according to any one of [1] to [5], wherein the anionic surfactant (s2) contains an oxyalkylene unit in the molecule.
[7] The production method according to any one of [1] to [6], wherein the polymethylsilsesquioxane particles have a number average particle diameter of 0.005 μm or more and 10.0 μm or less.
[8] The production method according to any one of [1] to [7], wherein the precipitation liquid (b) further contains polymethylsilsesquioxane seed particles.

Although the polymethylsilsesquioxane particles obtained by the production method of the present invention have a uniform particle diameter, the polymethylsilsesquioxane particles do not aggregate with each other, and clogging in the filtration step is suppressed. Therefore, the productivity is very high and the dispersion stability in the organic solvent is good.
Furthermore, according to the production method of the present invention, polymethylsilsesquioxane particles having a uniform particle diameter can be efficiently produced by an industrially advantageous method over a micron-size, submicron-size, or nano-size region. Can do. Therefore, the polymethylsilsesquioxane particles obtained by the production method of the present invention can achieve both uniformity in particle diameter and dispersion stability in an organic solvent.

The production method of the present invention comprises a hydrolyzate containing a hydrolyzate of a compound represented by formula (1) (hereinafter sometimes referred to as “compound (1)”), water and an anionic surfactant (s1). (A) and
CH ₃ Si (OR) ₃ (1)
[In formula (1), R represents a C1-C6 alkyl group. ]
The method includes a step of mixing water, a base catalyst, and a precipitate (b) containing an anionic surfactant (s2).
Since both the hydrolysis liquid (a) and the precipitation liquid (b) contain an anionic surfactant, the reaction liquid is mixed when the hydrolysis liquid (a) and the precipitation liquid (b) are mixed. It becomes easy to mix uniformly, and the condensation reaction of the hydrolyzate of the compound (1) easily proceeds uniformly. As a result, nano-sized to micron-sized polymethylsilsesquioxane particles can be produced with a uniform particle size, and the dispersion stability of the polymethylsilsesquioxane particles is also improved.

  The hydrolyzate (a) contains a hydrolyzate of compound (1), water, and an anionic surfactant (s1).

In the above formula (1), R is an alkyl group having 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms, more preferably 1 to 2 carbon atoms), and may be linear, branched or cyclic. May be. Examples of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a cyclopentyl group, and a cyclohexyl group. It is done.
As the compound (1), one or a combination of two or more can be used, and examples thereof include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, and methyltriisopropoxysilane.

The hydrolyzate of compound (1) is a compound containing —OH (silanol group) formed by hydrolysis of —OR, and includes CH ₃ Si (OR) ₂ (OH), CH ₃ Si (OR) ( OH) ₂ , CH ₃ Si (OH) _{3 and the} like, and it is preferable to include CH ₃ Si (OH) ₃ . The hydrolyzate of the compound (1) is a compound in which a part of —OH (silanol group) contained in the hydrolyzate is condensed to form a Si—O—Si bond (hereinafter referred to as “partial condensate”). May be included.). Even if a part of -OH (silanol group) contained in the hydrolyzate is condensed, the anionic surfactant is contained in the hydrolyzate (a) and the precipitate (b), so that the reaction is uniform. Can proceed.

  In the hydrolyzate (a), the molar concentration of silicon atoms contained in the hydrolyzate of compound (1) is preferably 0.1 mmol / g or more, more preferably 1 mmol / g or more, and even more preferably 2 mmol. / G or more, preferably 10 mmol / g or less, more preferably 7 mmol / g or less, and still more preferably 5 mmol / g or less.

  Examples of the anionic surfactant (s1) include aliphatic monocarboxylates, polyoxyethylene alkyl ether carboxylates, carboxylic acid type anionic surfactants such as fatty acid oils; dialkyl sulfosuccinates, polyoxyethylenes Sulfonic acid type anionic surfactants such as alkylsulfosuccinates, alkanesulfonates, linear alkylbenzenesulfonates, branched alkylbenzenesulfonates, naphthalenesulfonate-formaldehyde condensates, alkylnaphthalenesulfonates; Sulfate ester type anionic surfactants such as alkyl sulfates, polyoxyalkylene alkyl ether sulfates, and oil sulfates; alkyl phosphates, alkyl phosphate esters, polyoxyethylene alkyl ether phosphates, polyoxy esters Phosphoric ester type anionic surfactants such as lenalkyl aryl ether phosphates, etc., and sulfonic acid type anionic surfactants and sulfate ester type anionic surfactants are preferred, sulfate type anionic surfactants An activator is more preferred.

  Specific examples of the anionic surfactant (s1) include polyoxyethylene styrenated phenyl ether ammonium sulfate, polyoxyalkylene branched decyl ether sulfate sodium (preferably polyoxyethylene branched decyl ether sodium sulfate), polyoxyethylene Polyoxyethylene such as ammonium isodecyl ether sulfate, sodium polyoxyethylene tridecyl ether sulfate, sodium polyoxyethylene lauryl ether sulfate, ammonium polyoxyethylene lauryl ether sulfate, ammonium polyoxyethylene oleyl cetyl ether sulfate, sodium polyoxyethylene oleyl cetyl ether sulfate Alkyl ether sulfate; polyoxyethylene tridecyl ether phosphate, polyoxyethylene Lauryl ether phosphate ester / monoethanolamine salt, polyoxyethylene alkyl (C8) ether phosphate ester, polyoxyethylene alkyl (C8) ether phosphate ester / monoethanolamine salt, polyoxyethylene alkyl (C12,13) ether Polyoxyethylene alkyl ether phosphates such as phosphate esters and polyoxyethylene alkyl (C10) ether phosphate esters; Polyoxyethylene alkyl ether carboxylates such as sodium polyoxyethylene lauryl ether acetates; Polyoxyethylene lauryl ether sulfosuccinates Polyoxyethylene alkyl sulfosuccinates such as disodium acid and polyoxyethylene alkyl (C12-14) sulfosuccinate; polyoxyethylene Polyoxyethylene alkyl aryl ether phosphates such as tylene pheny ether phosphate; Fatty acid oils such as sodium oleate and castor oil potassium; Alkyl sulfate salts such as sodium lauryl sulfate and ammonium lauryl sulfate; Sodium dodecylbenzenesulfonate Alkyl benzene sulfonates; alkyl naphthalene sulfonates; alkane sulfonates; dialkyl sulfosuccinates; alkyl phosphate esters, naphthalene sulfonic acid-formaldehyde condensates, and the like.

Further, as the anionic surfactant (s1), an oxyalkylene unit (—R ¹ O— unit (R ¹ represents an alkylene group having 2 to 3 carbon atoms, preferably an ethylene group) in the molecule). ) Is preferably included. It becomes easier to make the particle diameter of the polymethylsilsesquioxane particles more uniform, and the resulting polymethylsilsesquioxane particles can be made closer to a true sphere. Specifically, anionic interfaces containing oxyethylene units such as polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkyl sulfosuccinate, polyoxyethylene alkyl aryl ether phosphate, etc. An activator is preferable, polyoxyethylene alkyl ether sulfate is more preferable, and polyoxyethylene styrenated phenyl ether sulfate ammonium salt, polyoxyethylene alkyl ether sodium sulfate, and polyoxyethylene alkyl ether ammonium sulfate are more preferable.

The content of the anionic surfactant (s1) is preferably 0.1 parts by mass or more, more preferably 1 part by mass with respect to 100 parts by mass of the compound (1) used in the hydrolyzate (a). Part or more, more preferably 3 parts by weight or more, particularly preferably 5 parts by weight or more, more preferably 10 parts by weight or more, preferably 50 parts by weight or less, more preferably 30 parts by weight or less. More preferably, it is 20 parts by mass or less. Moreover, when seed particle | grains are contained in precipitation liquid (b) so that it may mention later, content of anionic surfactant (s1) is 100 mass parts of compounds (1) used for hydrolysis liquid (a). It is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, further preferably 3 parts by mass or more, preferably 20 parts by mass or less, more preferably 15 parts by mass or less, More preferably, it is 5 mass parts or less.
When the amount of the anionic surfactant used is increased, the particle diameter of the polymethylsilsesquioxane particles is likely to be uniform, and aggregation of the polymethylsilsesquioxane particles is easily suppressed. Moreover, when the usage-amount of anionic surfactant is suppressed, it becomes easy to reduce foaming of a reaction liquid, and it becomes easy to suppress the production | generation of a coarse particle.

It is preferable that the hydrolyzed liquid (a) further contains an acid catalyst. By containing an acid catalyst in the hydrolyzed liquid (a), it becomes easy to control the hydrolysis reaction of the compound (1) and its hydrolyzate. As the acid catalyst contained in the hydrolyzed liquid (a), either an organic acid or an inorganic acid can be used, and an aqueous solution thereof is preferably used. More specifically, examples of the organic acid include formic acid, acetic acid, propionic acid, oxalic acid, and citric acid, and examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid. An organic acid is preferable from the viewpoint of excellent handleability, and acetic acid is particularly preferable.
When the acid catalyst is contained in the hydrolyzed liquid (a), the content thereof is preferably 0.001 mol or more with respect to 100 mol of silicon atoms contained in the hydrolyzate of the compound (1). Preferably it is 0.01 mol or more, it is preferable that it is 0.5 mol or less, More preferably, it is 0.3 mol or less, More preferably, it is 0.1 mol or less.

  The pH of the hydrolyzate (a) is preferably 2.0 or more, more preferably 2.5 or more, still more preferably 3.0 or more, and preferably 5.5 or less, more preferably Is 4.5 or less, more preferably 4.0 or less.

  The charge ratio of water and compound (1) used in the hydrolyzate (a) (water / compound (1)) is preferably 2 or more, more preferably 4 or more, and still more preferably, on a molar basis. It is 6 or more, preferably 20 or less, more preferably 15 or less, and still more preferably 10 or less.

The hydrolyzate (a) may contain alcohol (ROH). Examples of the alcohol include a group in which —OH is bonded to the group exemplified as R.
The alcohol content is preferably 10% by mass or more, more preferably 20% by mass or more, still more preferably 30% by mass or more, and 50% by mass or less in 100% by mass of the hydrolyzate (a). Preferably, it is 40 mass% or less, more preferably 37 mass% or less.

  The total content of the hydrolyzate of compound (1), water, the acid catalyst used as necessary, the anionic surfactant (s1), and the alcohol contained as necessary is the hydrolysis liquid. (A) It is preferable that it is 80 mass% or more in 100 mass%, More preferably, it is 90 mass% or more, More preferably, it is 95 mass% or more, Most preferably, it is 99 mass% or more.

The hydrolyzed liquid (a) can be produced by mixing the compound (1), water, an anionic surfactant (s1), and an acid catalyst used as necessary. By hydrolyzing the compound (1) using an acid catalyst, the hydrolysis reaction easily proceeds uniformly.
In addition, a step of preparing a preliminary hydrolysis liquid by mixing the compound (1), water and an acid catalyst used as necessary, and the preliminary hydrolysis liquid and the anionic surfactant (s1) It is preferable to manufacture by the process of preparing a hydrolyzed liquid (a) by mixing. By preparing a prehydrolyzed liquid in advance and mixing this prehydrolyzed liquid and the anionic surfactant (s1), the influence of the anionic surfactant (s1) on the hydrolysis reaction is suppressed and obtained. Control of the particle diameter of the polymethylsilsesquioxane particles to be produced becomes easy.

  The preliminary hydrolysis liquid contains a hydrolyzate of compound (1), an acid catalyst used as necessary, and water, and may contain alcohol (ROH).

  The pH of the prehydrolyzed solution is preferably 2.0 or more, more preferably 2.5 or more, still more preferably 3.0 or more, and preferably 5.5 or less, more preferably 4.5 or less, more preferably 4.0 or less.

The temperature at which the compound (1), water, the acid catalyst used as necessary, and the anionic surfactant (s1) mixed at the same time as necessary are preferably 0 ° C. or higher. Preferably it is 10 degreeC or more, More preferably, it is 15 degreeC or more, It is preferable that it is 80 degreeC or less, More preferably, it is 50 degreeC or less, More preferably, it is 40 degreeC or less.
In addition, the time for mixing the compound (1), water, the acid catalyst used as necessary, and the anionic surfactant (s1) mixed at the same time as necessary is preferably 10 minutes or more. More preferably, it is 20 minutes or more, More preferably, it is 30 minutes or more, It is preferable that it is 200 minutes or less, More preferably, it is 120 minutes or less, More preferably, it is 90 minutes or less.
When the compound (1) is hydrolyzed, -OR contained in the compound (1) is sequentially converted to -OH, and the produced -OHs are condensed to form a Si-O-Si bond. These hydrolysis / condensation reactions may proceed in parallel. When mixing the hydrolyzed liquid (a) and the precipitated liquid (b) by controlling the temperature and time during the preparation to the above ranges. Furthermore, it becomes easy to control the degree of hydrolysis / condensation reaction of compound (1) within an appropriate range.

  The precipitate (b) contains water, a base catalyst, and an anionic surfactant (s2). By using a base catalyst for the precipitate (b), the speed of the condensation reaction can be increased.

  Examples of the base catalyst include metal hydroxides (preferably alkali metal hydroxides) such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; amines such as ammonia, monomethylamine, and dimethylamine. Among them, amines are preferable, and ammonia is particularly preferable because impurities that limit the use of the generated polymethylsilsesquioxane particles can be reduced, and removal from the particles is easy.

  The content of the base catalyst contained in the precipitate (b) is 0.01 mol or more with respect to 100 mol of silicon atoms contained in the hydrolyzate of the compound (1) in the hydrolyzate (a). Is more preferably 0.05 mol or more, further preferably 0.1 mol or more, particularly preferably 1 mol or more, preferably 20 mol or less, more preferably 15 mol or less. More preferably, it is 10 mol or less.

  Further, the pH of the precipitation liquid (b) is preferably 8.0 or more, more preferably 8.5 or more, still more preferably 9.0 or more, and preferably 13.0 or less, More preferably, it is 12.5 or less, More preferably, it is 12.0 or less.

  The anionic surfactant (s2) may be the same as or different from the anionic surfactant (s1), and examples thereof include the same compounds as those exemplified as the anionic surfactant (s1). Of these, sulfonic acid type anionic surfactants and sulfate ester type anionic surfactants are preferred, and sulfate ester type anionic surfactants are more preferred.

In addition, the anionic surfactant (s2) includes a —R ¹ O-unit (R ¹ represents an alkylene group having 2 to 3 carbon atoms, preferably an ethylene group) in the molecule. preferable. It becomes easier to make the particle diameter of the polymethylsilsesquioxane particles more uniform.

  The content of the anionic surfactant (s2) is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, and still more preferably 0.000% by mass or more in 100% by mass of the precipitate (b). 01% by mass or more, particularly preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and preferably 5% by mass or less, more preferably 1% by mass or less, Preferably it is 0.5 mass% or less.

  The precipitation liquid (b) may contain polymethylsilsesquioxane seed particles (hereinafter sometimes simply referred to as “seed particles”). The coexistence of the seed particles condenses the —OH groups (silanol groups) contained in the seed particles and the —OH groups (silanol groups) contained in the compound (1), so that polymethyl is formed around the seed particles. Since silsesquioxane is formed, the particle diameter of the resulting polymethylsilsesquioxane particles can be easily controlled. In particular, sub-micron- and micron-sized polymethylsilsesquioxane particles can be produced. As seed particles, polymethylsilsesquioxane particles (homopolymer of compound (1)) are preferred.

The number average particle size of the seed particles may be adjusted according to the target particle size, for example, preferably 0.05 μm or more, more preferably 0.1 μm or more, and further preferably 0.2 μm or more. Yes, it is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less.
The particle diameter of the seed particles can be measured by a light scattering method when the number average particle diameter is less than 1 μm, and when the number average particle diameter is 1 μm or more, it is measured by a precision particle size distribution measuring apparatus using the Coulter principle. be able to.

The coefficient of variation in the particle size of the seed particles is preferably 40% or less, more preferably 30% or less, and still more preferably from the viewpoint of narrowing the particle size distribution of the finally obtained polymethylsilsesquioxane fine particles. Is preferably 20% or less, and is preferably as small as possible. For example, 2% or more, and further 3% or more is allowed.
The variation coefficient of the particle diameter is a value represented by the following formula.
Coefficient of variation of particle diameter (%) = (standard deviation of particle diameter / number average particle diameter) × 100

  When seed particles are contained in the precipitation liquid (b), the ratio of the seed particles is preferably 0.1% by mass or more, more preferably 1% by mass or more in 100% by mass of the precipitation liquid (b). More preferably, it is 2% by mass or more, preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 12% by mass or less.

  When seed particles are contained in the precipitation liquid (b), silicon atoms contained in the seed particles in the precipitation liquid (b) are silicon atoms contained in the hydrolyzate of the compound (1) in the hydrolysis liquid (a). The amount is preferably 0.01 mol or more, more preferably 0.05 mol or more, still more preferably 0.1 mol or more, and preferably 5 mol or less, more preferably 3 mol with respect to 1 mol. Hereinafter, it is more preferably 2 mol or less.

  Moreover, when seed particles are contained in the precipitate (b), the content of the base catalyst contained in the precipitate (b) is the silicon contained in the hydrolyzate of the compound (1) in the hydrolyzate (a). The amount is preferably 0.01 mol or more, more preferably 0.05 mol or more, and preferably 10 mol or less, more preferably 5 mol or less, still more preferably 1 mol with respect to 100 mol of atoms. It is as follows.

  Moreover, when seed particles are included in the precipitate (b), an acid catalyst may be included. Examples of the acid catalyst include the same catalysts as the acid catalyst used in the hydrolyzate (a), organic acids are preferable, and acetic acid is particularly preferable. The content of the acid catalyst is preferably 0.00001 mol or more with respect to 1 mol of silicon atoms contained in the hydrolyzate of compound (1) in the hydrolyzate (a), more preferably 0.00005. Mol or more, more preferably 0.0001 mol or more, preferably 0.1 mol or less, more preferably 0.05 mol or less, still more preferably 0.01 mol or less.

  When seed particles are contained in the precipitation liquid (b), the pH of the precipitation liquid (b) is preferably 8.0 or more, more preferably 8.5 or more, and 13.0 or less. More preferably, it is 12.0 or less, More preferably, it is 11.0 or less.

  When seed particles are contained in the precipitate (b), the content of the anionic surfactant is preferably 0.001% by mass or more, more preferably 0.005, in 100 mass of the precipitate (b). It is preferably at least 0.01 mass%, more preferably at most 0.5 mass%, even more preferably at most 0.3 mass%, still more preferably at most 0.1 mass%.

  As the precipitation liquid (b) containing seed particles, one prepared by mixing water, a base catalyst, an anionic surfactant (s2), and seed particles may be used, or seed particles were prepared. The reaction solution may be used as the precipitation solution (b).

  From the viewpoint of uniformity of the particle diameter, the seed particle is, for example, a reaction liquid containing a hydrolyzate of the compound (1) by mixing the compound (1), an acid catalyst, water, and an anionic surfactant ( After obtaining d), it can be produced by mixing the reaction liquid (d) and a base catalyst. The reaction liquid (d) may be prepared by simultaneously mixing the compound (1), an acid catalyst, water, and an anionic surfactant, or the compound (1), an acid catalyst, It may be prepared by first mixing with water and then mixing with an anionic surfactant. The obtained seed particles may be used as a dry powder by filtration, drying, crushing or the like, if necessary.

  When preparing the reaction solution (d), the amount of water charged is preferably 10 mol or more, more preferably 20 mol or more, relative to 1 mol of silicon atoms contained in the hydrolyzate of compound (1). More preferably, it is 30 mol or more, preferably 200 mol or less, more preferably 150 mol or less, still more preferably 120 mol or less.

Furthermore, by mixing the reaction liquid (d) and the base catalyst, condensation proceeds between —OH groups (silanol groups) contained in the hydrolyzate of the compound (1), and seed particles are formed. In order to increase the degree of condensation of —OH groups (silanol groups), it is preferable to age the seed particles. The aging temperature is preferably 20 ° C or higher, more preferably 30 ° C or higher, further preferably 40 ° C or higher, preferably 70 ° C or lower, and more preferably 65 ° C or lower.
The aging time is preferably 30 minutes or more, more preferably 50 minutes or more, preferably 200 minutes or less, more preferably 120 minutes or less, and still more preferably 90 minutes or less.

  By mixing the hydrolyzed liquid (a) and the precipitated liquid (b), the condensation reaction of —OH groups (silanol groups) contained in the hydrolyzate of the compound (1) proceeds to make Si—O—. Si bonds are formed, and polymethylsilsesquioxane particles can be obtained. Since an anionic surfactant is contained in both the hydrolyzed liquid (a) and the precipitated liquid (b), it becomes easy to mix uniformly from the beginning of mixing, and the condensation reaction proceeds evenly. It becomes possible to obtain polymethylsilsesquioxane particles having a uniform diameter. The obtained polymethylsilsesquioxane particles are preferably in a dispersed state in the reaction solution.

  The method of mixing the hydrolyzed liquid (a) and the precipitated liquid (b) is not particularly limited. 1) After preparing the hydrolyzed liquid (a) and the precipitated liquid (b), the hydrolyzed liquid (a) is added all at once. , Continuous dripping, or a method of feeding into the precipitation liquid (b) through a nozzle or the like, 2) after preparing the hydrolysis liquid (a) and the precipitation liquid (b), adding the precipitation liquid (b) at a time, Any method such as continuous dripping or a method of feeding into the hydrolyzate (a) through a nozzle or the like can be applied.

Among them, the method in which the hydrolyzed liquid (a) and the precipitated liquid (b) are adjusted, and then the hydrolyzed liquid (a) is continuously dropped onto the precipitated liquid (b), the particle diameter is uniformly controlled and the particles are aggregated. Is preferable in that it can be efficiently prevented.
Here, the dropping time when the hydrolyzed liquid (a) is continuously dropped is preferably 10 minutes to 300 minutes, more preferably 30 to 200 minutes. The dropping rate of the hydrolyzate (a) is preferably 0.5 g / min or more, more preferably 1 g / min or more, still more preferably 1.5 g / min or more, and 10 g / min or less. Preferably, it is 7 g / min or less, more preferably 5 g / min or less.

  The hydrolyzate (a) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 12 parts by mass or more, and 60 parts by mass with respect to 100 parts by mass of the precipitate (b). It is preferable that it is below, More preferably, it is 50 mass parts or less, More preferably, it is 45 mass parts or less.

  In the mixed liquid (c) obtained by mixing the hydrolyzed liquid (a) and the precipitated liquid (b), the molar ratio of water and silicon atoms contained in the hydrolyzate of the compound (1) (water / Si) Is preferably 20 or more, more preferably 30 or more, still more preferably 40 or more, and preferably 120 or less, more preferably 100 or less, still more preferably 90 or less.

  The pH of the mixed solution (c) is preferably 8.0 or more, more preferably 8.5 or more, still more preferably 9.0 or more, and preferably 13.0 or less, more preferably. Is 12.5 or less, more preferably 12.0 or less.

  By mixing the hydrolyzed liquid (a) and the precipitated liquid (b), dehydration condensation of the hydrolyzate of the compound (1) proceeds, and polymethylsilsesquioxane particles are precipitated. The reaction temperature at the time of precipitation is preferably 10 ° C. or higher, more preferably 15 ° C. or higher, preferably 40 ° C. or lower, more preferably 35 ° C. or lower. When seed particles are contained in the precipitate (b), the reaction temperature is preferably 10 ° C. or higher, more preferably 15 ° C. or higher, and preferably 70 ° C. or lower.

  Further, from the viewpoint of promoting dehydration condensation of the hydrolyzate of compound (1), it is preferable to perform aging after adding the entire amount of the hydrolyzate (a). The aging temperature is preferably 25 ° C or higher, more preferably 40 ° C or higher, further preferably 45 ° C or higher, preferably 70 ° C or lower, more preferably 65 ° C or lower. When seed particles are contained in the precipitate (b), it is preferably 25 ° C. or higher, more preferably 40 ° C. or higher, still more preferably 45 ° C. or higher, and preferably 70 ° C. or lower, more preferably It is 65 degrees C or less.

The number average particle diameter of the obtained polymethylsilsesquioxane particles is preferably 0.005 μm or more, more preferably 0.01 μm or more, and preferably 10.0 μm or less, and 5.0 μm or less. Is more preferably 3.0 μm or less, and most preferably 2.5 μm or less.
The particle size of polymethylsilsesquioxane particles can be measured by the light scattering method when the number average particle size is less than 1 μm, and when the number average particle size is 1 μm or more, the precise particle size distribution using the Coulter principle It can be measured by a measuring device.
Further, the coefficient of variation of the particle diameter of the polymethylsilsesquioxane particles is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less. In addition, it is allowed to be 3% or more.

The polymethylsilsesquioxane particles obtained by the production method of the present invention are present in a dispersed state in the reaction solution, and such a reaction solution can be used as a dispersion (dispersion) as it is. Further, it can be recovered and used as a fine powder by further processing such as filtration, drying and crushing.
For drying to obtain a fine powder, a dryer such as a spray dryer or conical ribbon mixing can be used. However, the drying temperature for fine powdering is from the viewpoint of redispersibility of the resulting fine powder in a solvent or resin. 110 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 60 ° C. or lower.

  When polymethylsilsesquioxane particles are used as a dispersion (dispersion), the water / alcohol mixed solvent contained in the reaction solution is replaced with various organic solvents as necessary to obtain an organic solvent dispersion (organic solvent). (Dispersion liquid).

  The organic solvent that can be used in the organic solvent substitution step can be appropriately selected according to the purpose of use. For example, a saturated or unsaturated hydrocarbon solvent, a halogenated hydrocarbon solvent, an alcohol solvent, an ether solvent. Preferred are ester solvents, ketone solvents and the like.

  Examples of the organic solvent include saturated hydrocarbon solvents such as hexane, heptane and cyclohexane; unsaturated hydrocarbon (aromatic hydrocarbon) solvents such as benzene, toluene, xylene, monochlorobenzene and dichlorobenzene; chloroform and dichloromethane Halogenated hydrocarbon solvents: methanol, ethanol, isopropanol, tert-butyl alcohol, n-butanol, cyclohexanol, benzyl alcohol, ethylene glycol, propylene glycol, glycerin, 2-methoxyethanol, 2-ethoxyethanol, 2-iso Alcohol solvents such as propoxyethanol and 2-butoxyethanol; dioxane, anisole, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol Ether solvents such as ethyl monomethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and tetrahydrofuran; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, methyl acetate, ethyl acetate, propyl acetate And ester solvents such as butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; Among these organic solvents, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone are preferable because they are excellent in solubility and compatibility with various resins and are easy to use industrially at an appropriate boiling point.

  Examples of the method for replacing the organic solvent include a method in which an organic solvent is added for distillation, a method using a liquid separation treatment, and the like.

  Prior to organic solvent replacement, the pH of the reaction solution is 8.0 or higher (preferably 8.5 or higher, more preferably 9.5 or higher) in advance, 13.0 or lower (preferably 12.5 or lower, more preferably It is preferable to adjust to 11.5 or less. The pH of the reaction solution can be adjusted using the acid or base exemplified as the acid catalyst or base catalyst. The acid is preferably the organic acid, and the base is preferably the amine.

  What is necessary is just to adjust the quantity of the organic solvent used for organic solvent substitution according to the kind of organic solvent, for example, it is preferable that it is 10 mass parts or more with respect to 100 mass parts of reaction liquids, More preferably, 20 mass parts or more More preferably, it is 30 parts by mass or more, preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and still more preferably 100 parts by mass or less.

  When replacing the organic solvent by a liquid separation treatment, the solvent is replaced by separating into two layers using an organic solvent that is not miscible with the polymethylsilsesquioxane particle dispersion (reaction solution) obtained by the method described above. From the viewpoint of efficiently transferring the polymethylsilsesquioxane particles to the organic solvent layer, it is preferable to add a highly polar solvent that is miscible with the polymethylsilsesquioxane particle dispersion (reaction solution). It is preferable to add an alcohol solvent. As the alcohol solvent, methanol, ethanol or 2-propanol is preferably used. The amount of the alcohol solvent used is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, still more preferably 30 parts by mass or more, and 100 parts by mass or less with respect to 100 parts by mass of the reaction solution. Is more preferable, 80 mass parts or less, More preferably, it is 60 mass parts or less.

In the case of replacing the organic solvent by a liquid separation treatment, the treatment temperature is appropriately selected depending on the boiling point of the organic solvent used, etc., but is preferably 0 ° C. or higher, more preferably 5 ° C. or higher, more preferably 10 ° C. or higher. It is preferable that it is 50 degrees C or less, More preferably, it is 45 degrees C or less, More preferably, it is 40 degrees C or less.
When replacing the organic solvent by a liquid separation treatment, it is preferable to mix and stir the reaction solution and the organic solvent, and the stirring speed is appropriately selected depending on the shape, size, or amount of the stirring blade to be used, but 5 rpm or more More preferably, it is 10 rpm or more, More preferably, it is 20 rpm or more, It is preferable that it is 300 rpm or less, More preferably, it is 250 rpm or less, More preferably, it is 200 rpm or less. Moreover, it is preferable that stirring time is 10 minutes or more, More preferably, it is 30 minutes or more, More preferably, it is 60 minutes or more.

  In the obtained organic solvent dispersion of polymethylsilsesquioxane particles (hereinafter sometimes simply referred to as “dispersion”), the content of the polymethylsilsesquioxane particles is 100% by mass of the organic solvent dispersion. The content is preferably 1% by mass or more, more preferably 3% by mass or more, and preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less.

  The polymethylsilsesquioxane particles obtained as described above have a uniform particle diameter and good dispersibility in an organic solvent. For this reason, for example, anti-blocking agents and slipperiness-imparting agents for various films such as polyolefin films, polyester films, polyimide films and fluororesin films; coating agents for polymer materials such as various films and molded articles, or addition for coating agents Agents: modifiers for various resins such as viscosity, thixotropy, viscoelasticity, or strength; in-plane spacers for liquid crystal display elements, seal spacers for liquid crystal display elements, spacers for EL display elements, spacers for touch panels, ceramics and plastics Spacers such as gap maintaining agents between various substrates such as: sealing materials for semiconductors, sealing materials for liquid crystals, sealing materials for LED light emitting elements, etc .; light diffusion films, light diffusion plates, conductive materials Light diffusion agents such as light plates and antiglare films; cosmetic additives such as white extender pigments; dental materials, etc. Mentioned, it is applicable to the known applications, such as silica particles and organic resin particles.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. Of course, it is possible to implement them, and they are all included in the technical scope of the present invention. In the following, “part” means “part by mass” and “%” means “mass%” unless otherwise specified.
Various physical properties were measured and evaluated by the following methods.

[Measurement of number average particle size and coefficient of variation (CV value) of polymethylsilsesquioxane particles having a number average particle size of less than 1 μm]
The obtained polymethylsilsesquioxane particle dispersion was diluted with ion-exchanged water and measured with a light scattering particle size distribution analyzer (“NicompMODEL380” manufactured by Particle Sizing Systems), and the number average particle diameter (μm) was measured. This value was determined as the average particle size of the polymethylsilsesquioxane particles. The standard deviation was calculated based on the number average particle size and the particle size obtained by the above apparatus, and the coefficient of variation (CV value:%) was obtained from the following equation.
Coefficient of variation (CV value:%) = 100 × (standard deviation / number average particle diameter)

[Measurement of number average particle diameter and coefficient of variation (CV value) of polymethylsilsesquioxane particles having a number average particle diameter of 1 μm or more]
The number average particle diameter of polymethylsilsesquioxane particles having a number average particle diameter of 1 μm or more was measured with a Coulter Multisizer III type (manufactured by Beckman Coulter, Inc.), and 30000 number average particle diameters (μm) were obtained. This value was defined as the average particle size of the polymethylsilsesquioxane particles. The standard deviation was calculated based on the number average particle size and the particle size obtained by the above apparatus, and the coefficient of variation (CV value:%) was obtained from the following equation.
Coefficient of variation (CV value:%) = 100 × (standard deviation / number average particle diameter)

[Dispersion stability evaluation]
The dispersion stability of the obtained polymethylsilsesquioxane particle dispersion was evaluated by the following method. Specifically, the filtration performance when the obtained polymethylsilsesquioxane particle dispersion was filtered using a 300 mesh (JIS mesh) wire mesh was evaluated according to the following criteria. Moreover, the presence or absence of the aggregate after filtration was determined visually.
○: There is almost no aggregate on the mesh after filtration.
(Triangle | delta): There exists an aggregate on a mesh after filtration.
X: Clogging occurred in the mesh during filtration.

Example 1 Example of Nanoparticle
100.5 parts by mass of deionized water and 0.21 part by mass of 10% aqueous acetic acid solution are added to a glass reaction kettle equipped with a stirrer, thermometer, dropping port and cooler, and methyltrimethoxysilane is stirred at room temperature. 100.5 parts by mass (hereinafter referred to as “MTMS”) was added from the dropping port, and MTMS was hydrolyzed. 20% of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Seiyaku Co., Ltd., Hightenol (registered trademark) NF-08) as an aqueous solution of anionic surfactant (s1) 50 minutes after completion of MTMS dropping 9.54 parts by mass of an aqueous solution was added to obtain a hydrolyzate (a1).

On the other hand, 686.6 parts by mass of deionized water and 3.18 parts by mass of 25% ammonia water were added to a glass reaction kettle equipped with a stirrer, thermometer, dropping port and cooler different from the above reaction kettle at room temperature. After stirring with a 20% aqueous solution of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Haitenol (registered trademark) NF-08, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an aqueous solution of the anionic surfactant (s2) 10 .32 parts by mass was added, and the mixture was further stirred at room temperature to obtain a precipitate (b1).
Subsequently, while stirring the said precipitation liquid (b1) at room temperature, when a hydrolysis liquid (a1) was dripped over 60 minutes from the dripping port to this precipitation liquid (b1), polymethylsilsesquioxane particle | grains precipitated. Then, after adding dropwise the entire amount of the hydrolyzed solution (a1), the reaction solution was heated to 60 ° C. and aged at 60 ° C. for 1 hour, and then the reaction solution was cooled and filtered through a 300 mesh dispersion stability. While evaluating, the dispersion liquid in which the polymethylsilsesquioxane particles (1) are dispersed was obtained. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

Example 2 Example of Nanoparticle
In Example 1, the aqueous solution of the anionic surfactant (s1) at the time of preparing the hydrolyzed liquid (a1) was changed to 9.54 parts by mass of a 20% aqueous solution of sodium lauryl sulfate to obtain a hydrolyzed liquid (a2) The aqueous solution of the anionic surfactant (s2) at the time of preparation of the liquid (b1) was changed to 10.32 parts by mass of a 20% aqueous solution of sodium lauryl sulfate to obtain a precipitation liquid (b2). The dispersion stability was evaluated by the same method as in Example 1 except that it was used instead of the liquid (b1), and a dispersion in which the polymethylsilsesquioxane particles (2) were dispersed was obtained. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

Example 3 Example of Nanoparticle
In Example 1, an aqueous solution of the anionic surfactant (s1) at the time of preparation of the hydrolyzate (a1) was prepared from polyoxyethylene alkyl ether sulfate ester salt (manufactured by Nippon Emulsifier Co., Ltd., New Coal (registered trademark) 1305-SN). The hydrolyzed liquid (a3) was changed to 9.54 parts by mass of a 20% aqueous solution, and the aqueous solution of the anionic surfactant (s2) at the time of preparing the precipitated liquid (b1) was replaced with polyoxyethylene alkyl ether sulfate (Japanese emulsifier). Changed to 10.32 parts by mass of a 20% aqueous solution of New Coal (registered trademark) 1305-SN), made into a precipitation liquid (b3), respectively, instead of the hydrolysis liquid (a1) and the precipitation liquid (b1) The dispersion stability was evaluated by the same method as in Example 1 except that the polymethylsilsesquioxane particles (3) were dispersed. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

Example 4 Example of Nanoparticle
In Example 1, the same method as in Example 1 except that an aqueous solution of the anionic surfactant (s1) was added to the reaction kettle before dropping the methyltrimethoxysilane when preparing the hydrolyzate (a1). Thus, dispersion stability was evaluated, and a dispersion in which polymethylsilsesquioxane particles (4) were dispersed was obtained. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

(Example 5 / Example of submicron particles)
To a glass reaction kettle equipped with a stirrer, a thermometer, a dropping port and a cooler, 123.16 parts by mass of deionized water and 0.26 parts by mass of a 10% aqueous acetic acid solution were added, and methyltrimethoxysilane was stirred at room temperature. 123.16 parts by mass (hereinafter referred to as “MTMS”) was added all at once from the dropping port, and MTMS was hydrolyzed. 30% after completion of MTMS dropping, 20% of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Seiyaku Co., Ltd., Hightenol (registered trademark) NF-08) as an aqueous solution of anionic surfactant (s1) 3.08 parts by mass of an aqueous solution was added to obtain a hydrolyzate (a5). The obtained hydrolysis liquid (a5) was used for seed particle growth of methylsilsesquioxane particles.

  On the other hand, after putting 607.18 parts by mass of deionized water into a glass reaction kettle equipped with a stirrer, thermometer, dropping port and cooler different from the above reaction kettle, 0.09 part by mass of 10% acetic acid aqueous solution And mixed uniformly by stirring. Next, 41.06 parts by mass of MTMS was added all at once, and MTMS was hydrolyzed by stirring for 20 minutes. At this time, the temperature of the reaction solution was raised from room temperature to 60 ° C. 20 minutes after the MTMS batch addition, polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Seiyaku Co., Ltd., Hightenol (registered trademark) NF-08) as an aqueous solution of anionic surfactant (s2) was further added. 1.03 parts by mass of a 20% aqueous solution was added and mixed uniformly to obtain a reaction solution (d5). Next, in a state where the obtained reaction liquid (d5) was kept at 60 ° C., 0.99 parts by mass of 25% ammonia water was added all at once to precipitate polymethylsilsesquioxane fine particles (seed particles), and seed particles A precipitate (b5) containing was obtained. Further, 244.79 parts by mass of the previously prepared hydrolysis liquid for seed particle growth (a5) was added dropwise to the reaction liquid to grow the particles. After dropwise addition of the entire amount of the hydrolyzate (a5), aging was performed at 60 ° C. for 1 hour, and then the reaction solution was cooled and filtered through a 300 mesh for evaluation of dispersion stability, and polymethylsilsesquioxane particles ( A dispersion in which 5) was dispersed was obtained. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

(Example 6 / Example of micron particles)
Methyltrimethoxysilane was added to a glass reaction kettle equipped with a stirrer, a thermometer, a dripping port and a cooler while adding 61.58 parts by mass of deionized water and 0.13 parts by mass of a 10% aqueous acetic acid solution while stirring at room temperature. 61.58 parts by mass (hereinafter referred to as “MTMS”) was added from the dropping port, and MTMS was hydrolyzed. 20% of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Seiyaku Co., Ltd., Hightenol (registered trademark) NF-08) as an aqueous solution of anionic surfactant (s1) 50 minutes after completion of MTMS dropping 1.54 parts by mass of an aqueous solution was added to obtain a hydrolyzate (a6). The obtained solution was used for seed particle growth of methylsilsesquioxane particles.
On the other hand, 669.01 parts by mass of deionized water was added to a glass reaction kettle equipped with a stirrer, thermometer, dripping port and cooler different from the above reaction kettle, and then 0.22 parts by mass of 10% aqueous acetic acid solution. And mixed uniformly by stirring. Next, 102.64 parts by mass of MTMS was added all at once, and MTMS was hydrolyzed by stirring for 30 minutes. At this time, the temperature of the reaction solution was raised from room temperature to 40 ° C. 30 minutes after the MTMS batch addition, polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Seiyaku Co., Ltd., Hightenol (registered trademark) NF-08) as an aqueous solution of anionic surfactant (s2) was further added. A reaction liquid (d6) was obtained by adding 2.57 parts by mass of a 20% aqueous solution and mixing uniformly. Next, 0.37 parts by mass of 25% ammonia water was added all at once while maintaining the obtained reaction liquid (d6) at 60 ° C. to precipitate polymethylsilsesquioxane fine particles (seed particles). A precipitate (b6) containing was obtained. Furthermore, 121.84 parts by mass of the previously prepared hydrolysis solution (a6) was added dropwise to the reaction solution to grow particles. After dropwise addition of the entire amount of the hydrolyzate (a6), aging was carried out at 30 ° C. for 50 minutes, and then the reaction solution was cooled and filtered through 300 mesh for evaluation of dispersion stability, and polymethylsilsesquioxane particles ( A dispersion in which 6) was dispersed was obtained. Table 1 shows each evaluation result of the obtained polymethylsilsesquioxane particles.

(Example 7 / Example of nanoparticle organic solvent dispersion)
In a glass reaction kettle equipped with a stirrer, thermometer, dropping port and cooler, polymethylsilsesquioxane particle dispersion obtained in Example 1 (hereinafter referred to as reaction solution, pH 10.2) 900. 0 parts by mass was added, and then 450.0 parts by mass of methyl isobutyl ketone (hereinafter referred to as MIBK) was added as an organic solvent, followed by stirring at room temperature at a stirring speed of 50 rpm. At this time, the solution in the reaction kettle was separated into two layers of an upper layer (MIBK layer) and a lower layer (reaction liquid layer). Next, 450.0 parts by mass of methanol as an alcohol solvent was added in three parts (150.0 parts by mass every 10 minutes), and after the total amount of methanol was added, the mixture was stirred at room temperature for 4 hours. It was confirmed that the polymethylsilsesquioxane particles dispersed in were transferred to the upper MIBK layer. Next, after separating the upper layer (MIBK layer), it was confirmed that the separated upper layer was allowed to stand for another 24 hours to slightly separate the aqueous layer as the lower layer. When the obtained upper layer was separated, 350.0 parts by mass of MIBK layer was obtained, and after adding 350.0 parts by mass of MIBK to this, it was concentrated using an evaporator to distill off the water remaining in the MIBK layer. As a result, polymethylsilsesquioxane particle MIBK dispersion (7) was obtained. When the obtained polymethylsilsesquioxane particle MIBK dispersion (7) was analyzed, the polymethylsilsesquioxane particle was contained in 9.8% by mass in 100% by mass of the MIBK dispersion (7). . The number average particle diameter of the polymethylsilsesquioxane particles in the MIBK dispersion (7) was 17.2 nm, and the polymethylsilsesquioxane particles were uniformly dispersed in the MIBK without aggregation.

(Comparative Example 1 / Nanoparticle Comparative Example)
In Example 1, the aqueous solution of the anionic surfactant (s2) added to the precipitation liquid (b1) was not added at the time of preparing the hydrolyzed liquid (a1), and 19.75 mass of the aqueous solution of the anionic surfactant (s2) was added. A dispersion in which the comparative polymethylsilsesquioxane particles (1) were dispersed was obtained in the same manner as in Example 1 except that the parts were used.

(Comparative Example 2 / Comparative Example of Nanoparticles)
In Example 1, the aqueous solution of the anionic surfactant (s1) added at the time of preparing the hydrolyzed liquid (a1) was 19.75 parts by mass, and the aqueous solution of the anionic surfactant (s2) was added to the precipitate (b1). A dispersion liquid in which comparative polymethylsilsesquioxane particles (2) were dispersed was obtained in the same manner as in Example 1 except that this was not done.

(Comparative Example 3 / Comparative Example of Submicron Particles)
In Example 4, the aqueous solution of the anionic surfactant (s2) added to the precipitate (b4) was not added at the time of preparing the hydrolyzate (a4), and 19.75 mass of the aqueous solution of the anionic surfactant (s2) added to the precipitate (b4). A dispersion in which comparative polymethylsilsesquioxane particles (3) were dispersed was obtained in the same manner as in Example 4 except that the parts were used.

(Comparative Example 4 / Comparative Example of Micron Particles)
In Example 5, the aqueous solution of the anionic surfactant (s2) added to the precipitate (b5) was not added at the time of preparing the hydrolyzate (a5), and 19.75 mass of the aqueous solution of the anionic surfactant (s2) added to the precipitate (b5). A dispersion in which comparative polymethylsilsesquioxane particles (4) were dispersed was obtained in the same manner as in Example 5 except that the parts were changed to parts.

  As can be seen from Table 1, the particles obtained by the production method of the present invention all have an increased coefficient of variation, have good dispersion stability, and achieve both uniformity in particle diameter and dispersion stability in organic solvents. It turns out that it is possible.

  The polymethylsilsesquioxane particles of the present invention have a uniform particle diameter and good dispersibility in an organic solvent. For this reason, for example, anti-blocking agents and slipperiness-imparting agents for various films such as polyolefin films, polyester films, polyimide films and fluororesin films; coating agents for polymer materials such as various films and molded articles, or addition for coating agents Agents: modifiers for various resins such as viscosity, thixotropy, viscoelasticity, or strength; in-plane spacers for liquid crystal display elements, seal spacers for liquid crystal display elements, spacers for EL display elements, spacers for touch panels, ceramics and plastics Spacers such as gap maintaining agents between various substrates such as: sealing materials for semiconductors, sealing materials for liquid crystals, sealing materials for LED light emitting elements, etc .; light diffusion films, light diffusion plates, conductive materials Light diffusion agents such as light plates and antiglare films; cosmetic additives such as white extender pigments; dental materials, etc. Mentioned, it is applicable to the known applications, such as silica particles and organic resin particles.

Claims (8)

A hydrolyzate (a) containing a hydrolyzate of the compound represented by formula (1), water and an anionic surfactant (s1);
CH ₃ Si (OR) ₃ (1)
[In formula (1), R represents a C1-C6 alkyl group. ]
The manufacturing method of the polymethylsilsesquioxane particle | grains including the process of mixing the precipitation liquid (b) containing water, a base catalyst, and an anionic surfactant (s2).   The production method according to claim 1, wherein the hydrolysis liquid (a) further contains an acid catalyst.   The mass ratio of the compound represented by the formula (1) and the anionic surfactant (s1) (anionic surfactant (s1) / the compound represented by the formula (1)) is 0.0005 or more and 0 The production method according to claim 1 or 2, which is 0.05 or less.   The manufacturing method according to any one of claims 1 to 3, wherein the hydrolyzate (a) has a pH of 2.0 or more and 5.5 or less.   The manufacturing method according to any one of claims 1 to 4, wherein the pH of the precipitate (b) is 8.0 or more and 13.0 or less.   The manufacturing method in any one of Claims 1-5 in which the said anionic surfactant (s2) contains an oxyalkylene unit in a molecule | numerator.   The production method according to claim 1, wherein the polymethylsilsesquioxane particles have a number average particle diameter of 0.005 μm or more and 10.0 μm or less.   The manufacturing method in any one of Claims 1-7 in which the said precipitation liquid (b) contains polymethylsilsesquioxane seed particle | grains further.