JP2007056177A - Method for producing resin particles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide resin particles which do not unite with each other after they are dispersed and have a sharp particle size distribution irrespective of the type and molecular weight of the resin. <P>SOLUTION: The method for producing the resin particles comprises dispersing a disperse phase (DP) comprising a precursor (b0) or a solvent solution thereof in a continuous phase (CP) through a microchannel (M), to thereby form particles (B0) comprising the precursor (b0) or particles (B0') comprising the solvent solution, subjecting the particles (B0') to a polymerization reaction, and further removing the solvent in the case of the particles (B0'), to obtain a dispersion of resin particles (B) comprising the resin (b). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing resin particles having a uniform particle diameter, and more particularly to a method for producing resin particles using a microchannel.

Conventionally, as a method for producing resin particles, a resin solution in which a resin is dissolved in a solvent is dispersed in an aqueous medium in the presence of a dispersing agent (auxiliary) such as a surfactant or a water-soluble polymer, and this is heated or reduced in pressure. A method (dissolving resin suspension method) for removing the solvent by a method is known (for example, see Patent Document 1). Further, a method is known in which a vinyl monomer is dispersed in a continuous phase via a microchannel and radically polymerized (see, for example, Patent Document 2).
JP 63-25664 A JP-A-2001-181309

However, the particle size uniformity of the particles obtained by the dissolved resin suspension method is insufficient, and there is a disadvantage that a classification step is required to make the particle size uniform. In addition, resin particles obtained by a method in which a vinyl monomer is dispersed through a microchannel are liable to coalesce at the time of particle contact, and have a drawback that the uniformity of the particle size is lowered.
An object of the present invention is to obtain resin particles having a sharp particle size distribution without causing the resin particles to coalesce after dispersion regardless of the type and molecular weight of the resin.

As a result of intensive studies to solve these problems, the present inventors have reached the present invention.
That is, the present invention disperses a precursor (b0) of a resin (b) or a dispersed phase (DP) composed of a solvent solution thereof into a continuous phase (CP) through a microchannel (M), thereby providing a precursor. Form particles (B0) composed of (b0) or particles (B0 ′) composed of a solvent solution thereof, and further subject the particles (B0 ′) to a polymerization reaction, and in the case of particles (B0 ′), further remove the solvent. To obtain a dispersion of resin particles (B) made of resin (b).

  The resin particles obtained by the production method of the present invention are resin particles having a sharp particle size distribution. For this reason, the resin particle excellent in the powder characteristic is obtained.

<Continuous phase (CP)>
Examples of the continuous phase (CP) include an aqueous liquid and an organic solvent. The aqueous liquid and organic solvent are preferably those in which the resin (b) is hardly soluble.
Examples of the aqueous liquid include water and a mixed solution of water and a water-soluble organic solvent (the ratio of the organic solvent is preferably 30% by weight or less). Examples of the water-soluble organic solvent include methanol, ethanol, isopropyl alcohol, dimethylformamide (DMF), tetrahydrofuran (THF), acetone, and the like.

Examples of the organic solvent include aromatic hydrocarbon solvents such as toluene, xylene, ethylbenzene, and tetralin; aliphatic or alicyclic hydrocarbon solvents such as n-hexane, n-heptane, mineral spirit, and cyclohexane; methyl chloride, Halogen solvents such as methyl bromide, methyl iodide, methylene dichloride, carbon tetrachloride, trichloroethylene, perchloroethylene; ethyl acetate, butyl acetate, methyl propionate, ethyl propionate, methoxybutyl acetate, methyl cellosolve acetate, ethyl cellosolve Ester or ester ether solvents such as acetate; ether solvents such as diethyl ether, tetrahydrofuran, dioxane, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether; , Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone; methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2-ethylhexyl alcohol, benzyl alcohol, etc. Examples include alcohol solvents; amide solvents such as dimethylformamide and dimethylacetamide; sulfoxide solvents such as dimethyl sulfoxide; heterocyclic compound solvents such as N-methylpyrrolidone; and mixed solvents of two or more of these. Of these, toluene, hexane, and cyclohexane are preferable.
The boiling point of the organic solvent is preferably 10 to 150 ° C., more preferably 30 to 100 ° C., and particularly preferably 40 to 90 ° C. from the viewpoint of solvent removability.

<Dispersed phase (DP)>
The dispersed phase (DP) is composed of the precursor (b0) of the resin (b) or a solvent solution thereof. As the solvent of the dispersed phase (DP) and the solvent (DP0), an organic solvent and an aqueous liquid exemplified by the above (CP) can be used.
The solvent (DP0) is preferably contained in an amount of 0 to 80% by weight, more preferably 10 to 60% by weight, based on the weight of the precursor (b0) of the resin (b).

  As a combination of the continuous phase (CP) and the solvent (DP0), when an aqueous liquid is used for (CP), an organic solvent is preferable when (DP0) is used, and when an organic solvent is used for (CP), (DP0) is aqueous. Liquid is preferred.

  A preferable range of the difference in solubility parameter between the solvent (DP0) of the dispersed phase (DP) and the medium (CP0) of the continuous phase (CP) is 5 to 17, more preferably 8 to 17.

  As the resin (b) of the present invention, a preferable one can be appropriately selected according to the use and purpose. In general, preferred resins (b) include polyurethane resins, epoxy resins, polyamide resins and polyester resins.

  The Mn, melting point, Tg, and SP value of the resin (b) may be appropriately adjusted within a preferable range depending on the application. For example, when the resin particles (B) are used as a slush molding resin or powder coating, the Mn in (b) is usually 2,000 to 500,000, preferably 4,000 to 200,000. The melting point (b) (measured by DSC, hereinafter the melting point is a measured value by DSC), usually 0 ° C. to 200 ° C., preferably 35 ° C. to 150 ° C. Tb of (b) is usually −60 ° C. to 100 ° C., preferably −30 ° C. to 60 ° C. The SP value of (b) is usually 7-18, preferably 8-14. When used as a standard particle for electronic component manufacturing spacers such as liquid crystal displays and electronic measuring machines, Mn in (b) is usually 20,000 to 10,000,000, preferably 40,000 to 2,000,000. The melting point of (b) (measured by DSC, hereinafter the melting point is a measured value by DSC), usually 40 ° C. to 300 ° C., preferably 70 ° C. to 250 ° C. Tb of (b) is usually −0 ° C. to 250 ° C., preferably 50 ° C. to 200 ° C. The SP value of (b) is usually 8-18, preferably 9-14. When used as a toner used for electrophotography, electrostatic recording, electrostatic printing, etc., the Mn of (b) is usually 1,000 to 5,000,000, preferably 2,000 to 500,000. The melting point of (b) (measured by DSC, hereinafter the melting point is a measured value by DSC), usually 20 ° C. to 300 ° C., preferably 80 ° C. to 250 ° C. The Tg of (b) is usually 20 ° C to 200 ° C, preferably 40 ° C to 200 ° C. The SP value of (b) is usually 8 to 16, preferably 9 to 14.

<Description of Precursor (b0)>
The precursor (b0) of the resin (b) is not particularly limited as long as it can be converted into the resin (b) by a chemical reaction. For example, the resin (b) is a condensation resin (for example, polyurethane resin, epoxy resin). In the case of (b0), a combination of a prepolymer (α) having a reactive group and a curing agent (β) is exemplified.

As the precursor (b0), a combination of a prepolymer (α) having a reactive group and a curing agent (β) can also be used. Here, “reactive group” means a group capable of reacting with the curing agent (β).
In this case, as a method for forming the resin (b) by reacting the precursor (b0), a dispersed phase containing a reactive group-containing prepolymer (α) and a curing agent (β) and, if necessary, a solvent (DP0) ( DP) is dispersed in the continuous phase (CP) through the microchannel (M), and if necessary, the reactive group-containing prepolymer (α) and the curing agent (β) are reacted with each other from the resin (b) by heating. A method of forming resin particles (B)
A reactive group-containing prepolymer (α) or a solvent solution thereof is dispersed in a continuous phase (CP) through a microchannel (M), and a curing agent (β) is added thereto and reacted to form a resin (b). A method of forming resin particles (B)
A method in which a reactive group-containing prepolymer (α) or a solvent solution thereof is dispersed in a continuous phase (CP) containing a curing agent (β) through a microchannel (M);
When the reactive group-containing prepolymer (α) is to be cured by reacting with water, the reactive group-containing prepolymer (α) or a solvent solution thereof is used when the continuous phase (CP) is an aqueous liquid. Examples thereof include a method of forming a resin particle (B) composed of (b) by reacting with water by dispersing in a continuous phase through the microchannel (M).

Examples of the combination of the reactive group contained in the reactive group-containing prepolymer (α) and the curing agent (β) include the following (K1) and (K2).
(K1): The reactive group of the reactive group-containing prepolymer (α) is a functional group (α1) capable of reacting with an active hydrogen compound, and the curing agent (β) is an active hydrogen group-containing compound (β1). There is a combination.
(K2): The reactive group contained in the reactive group-containing prepolymer (α) is an active hydrogen-containing group (α2), and the curing agent (β) is a compound (β2) that can react with the active hydrogen-containing group. combination. Among these, (K1) is more preferable from the viewpoint of the reaction rate in water.
In the combination (K1), the functional group (α1) capable of reacting with the active hydrogen compound includes an isocyanate group (α1a), a blocked isocyanate group (α1b), an epoxy group (α1c), an acid anhydride group (α1d) and And acid halide groups (α1e). Among these, (α1a), (α1b) and (α1c) are preferable, and (α1a) and (α1b) are particularly preferable. The blocked isocyanate group (α1b) refers to an isocyanate group blocked with a blocking agent.
Examples of the blocking agent include oximes [acetooxime, methyl isobutyl ketoxime, diethyl ketoxime, cyclopentanone oxime, cyclohexanone oxime, methyl ethyl ketoxime, etc.]; lactams [γ-butyrolactam, ε-caprolactam, γ-valerolactam Etc.]; C1-20 aliphatic alcohols [ethanol, methanol, octanol, etc.]; phenols [phenol, m-cresol, xylenol, nonylphenol, etc.]; active methylene compounds [acetylacetone, ethyl malonate, ethyl acetoacetate, etc.] Etc.]; basic nitrogen-containing compounds [N, N-diethylhydroxylamine, 2-hydroxypyridine, pyridine N-oxide, 2-mercaptopyridine, etc.]; and mixtures of two or more thereof. That. Of these, oximes are preferred, and methyl ethyl ketoxime is particularly preferred.

  Examples of the skeleton of the reactive group-containing prepolymer (α) include polyether (αw), polyester (αx), epoxy resin (αy), and polyurethane (αz). Among these, (αx), (αy) and (αz) are preferable, and (αx) and (αz) are particularly preferable. Examples of the polyether (αw) include polyethylene oxide, polypropylene oxide, polybutylene oxide, polytetramethylene oxide, and the like. Examples of polyester (αx) include polycondensates of diol (11) and dicarboxylic acid (13), polylactones (ring-opening polymerization products of ε-caprolactone), and the like. Examples of the epoxy resin (αy) include addition condensation products of bisphenols (such as bisphenol A, bisphenol F, and bisphenol S) and epichlorohydrin. Examples of polyurethane (αz) include polyaddition product of diol (11) and polyisocyanate (15), polyaddition product of polyester (αx) and polyisocyanate (15), and the like.

As a method of incorporating a reactive group into polyester (αx), epoxy resin (αy), polyurethane (αz), etc., (AA1): by using one of two or more constituent components excessively, A method of leaving a functional group at the end, (AA2): By using one of two or more constituent components in excess, the functional group of the constituent component can be left at the end and further reacted with the remaining functional group Examples include a method of reacting a compound containing a functional group and a reactive group.
In the above method (AA1), a hydroxyl group-containing polyester prepolymer, a carboxyl group-containing polyester prepolymer, an acid halide group-containing polyester prepolymer, a hydroxyl group-containing epoxy resin prepolymer, an epoxy group-containing epoxy resin prepolymer, a hydroxyl group-containing polyurethane prepolymer, an isocyanate A group-containing polyurethane prepolymer or the like is obtained. For example, in the case of a hydroxyl group-containing polyester prepolymer, the ratio of the constituent components is such that the ratio of the polyol (1) to the polycarboxylic acid (2) is the molar ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. ] Is usually 2/1 to 1/1, preferably 1.5 / 1 to 1/1, and more preferably 1.3 / 1 to 1.02 / 1. In the case of other skeleton and end group prepolymers, the ratios are the same except that the constituent components are changed.
In the said method (AA2), an isocyanate group containing prepolymer is obtained by making polyisocyanate react with the preprimer obtained by the said method (AA1), and blocked isocyanate group containing prepolymer is made to react with blocked polyisocyanate. A polymer is obtained, an epoxy group-containing prepolymer is obtained by reacting polyepoxide, and an acid anhydride group-containing prepolymer is obtained by reacting polyanhydride. The amount of the compound containing a functional group and a reactive group is, for example, when the isocyanate group-containing polyester prepolymer is obtained by reacting a hydroxyl group-containing polyester with a polyisocyanate, the ratio of the polyisocyanate is an isocyanate group [NCO], The molar ratio [NCO] / [OH] of the hydroxyl group [OH] of the hydroxyl group-containing polyester is usually 5/1 to 1/1, preferably 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1. 1.5 / 1. In the case of prepolymers having other skeletons and terminal groups, the ratio is the same except that the constituent components are changed.

  The number of reactive groups contained per molecule in the reactive group-containing prepolymer (α) is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is a piece. By setting it as the said range, the molecular weight of the hardened | cured material obtained by making it react with a hardening | curing agent ((beta)) becomes high. The number average molecular weight of the reactive group-containing prepolymer (α) is usually 500 to 30,000, preferably 1,000 to 20,000, more preferably 2,000 to 10,000. The weight average molecular weight of the reactive group-containing prepolymer (α) is 1,000 to 50,000, preferably 2,000 to 40,000, and more preferably 4,000 to 20,000. The viscosity of the reactive group-containing prepolymer (α) is usually not more than 2,000 poise, preferably not more than 1,000 poise at 100 ° C. Setting it to 2,000 poise or less is preferable in that resin particles (B) having a sharp particle size distribution can be obtained with a small amount of solvent.

  Examples of the active hydrogen group-containing compound (β1) include polyamine (β1a), polyol (β1b), polymercaptan (β1c) and water (β1d) which may be blocked with a detachable compound. Among these, preferred are (β1a), (β1b) and (β1d), more preferred are (β1a) and (β1d), and particularly preferred are blocked polyamines and (β1d ). (Β1a) is exemplified by those similar to polyamine (16). Preferred as (β1a) are 4,4'-diaminodiphenylmethane, xylylenediamine, isophoronediamine, ethylenediamine, diethylenetriamine, triethylenetetramine and mixtures thereof.

  Examples of the case where (β1a) is a polyamine blocked with a detachable compound include ketimine compounds obtained from the polyamines and ketones having 3 to 8 carbon atoms (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) And aldimine compounds, enamine compounds and oxazolidine compounds obtained from aldehyde compounds having 2 to 8 carbon atoms (formaldehyde, acetaldehyde).

  Examples of the polyol (β1b) are the same as the diol (11) and the polyol (12). Diol (11) alone or a mixture of diol (11) and a small amount of polyol (12) is preferred. Examples of the polymercaptan (β1c) include ethylenedithiol, 1,4-butanedithiol, 1,6-hexanedithiol, and the like.

  If necessary, a reaction terminator (βs) can be used together with the active hydrogen group-containing compound (β1). By using a reaction terminator in combination with (β1) at a certain ratio, it is possible to adjust (b) to a predetermined molecular weight. As the reaction terminator (βs), monoamine (diethylamine, dibutylamine, butylamine, laurylamine, monoethanolamine, diethanolamine, etc.); monoamine blocked (ketimine compound, etc.); monool (methanol, ethanol, isopropanol, butanol) And phenol; monomercaptan (such as butyl mercaptan and lauryl mercaptan); monoisocyanate (such as lauryl isocyanate and phenyl isocyanate); monoepoxide (such as butyl glycidyl ether) and the like.

  As the active hydrogen-containing group (α2) of the reactive group-containing prepolymer (α) in the combination (AA2), an amino group (α2a), a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group) (α2b), a mercapto group ( α2c), a carboxyl group (α2d), and an organic group (α2e) blocked with a compound from which they can be removed. Of these, (α2a), (α2b) and an organic group (α2e) blocked with a compound capable of removing an amino group are preferred, and (α2b) is particularly preferred. Examples of the organic group blocked with the compound from which the amino group can be removed include the same groups as in the case of (β1a).

  Examples of the compound (β2) capable of reacting with an active hydrogen-containing group include polyisocyanate (β2a), polyepoxide (β2b), polycarboxylic acid (β2c), polyanhydride (β2d), and polyacid halide (β2e). It is done. Of these, (β2a) and (β2b) are preferable, and (β2a) is more preferable.

  Examples of the polyisocyanate (β2a) include those similar to the polyisocyanate (15), and preferred ones are also the same. Examples of the polyepoxide (β2b) are the same as those of the polyepoxide (18), and preferred ones are also the same.

  Examples of the polycarboxylic acid (β2c) include dicarboxylic acid (β2c-1) and trivalent or higher polycarboxylic acid (β2c-2). (Β2c-1) alone and (β2c-1) and a small amount of ( A mixture of β2c-2) is preferred. Examples of the dicarboxylic acid (β2c-1) include the dicarboxylic acid (13), and examples of the polycarboxylic acid include those similar to the polycarboxylic acid (5), and preferable ones are also the same.

  Examples of the polycarboxylic acid anhydride (β2d) include pyromellitic acid anhydride. Examples of the polyacid halides (β2e) include the acid halides (acid chloride, acid bromide, acid iodide) of the above (β2c). Furthermore, a reaction terminator (βs) can be used together with (β2) if necessary.

  The ratio of the curing agent (β) is the ratio of the equivalent [α] of the reactive group in the reactive group-containing prepolymer (α) to the equivalent of the active hydrogen-containing group [β] in the curing agent (β) [α. ] / [Β] is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2. When the curing agent (β) is water (β1d), water is handled as a divalent active hydrogen compound.

  The resin (b) obtained by reacting the precursor (b0) comprising the reactive group-containing prepolymer (α) and the curing agent (β) is a constituent component of the resin particles (B). The weight average molecular weight of the resin (b) obtained by reacting the reactive group-containing prepolymer (α) and the curing agent (β) is usually 3,000 or more, preferably 3,000 to 10,000,000, more preferably 5,000 to 5,000. One million.

  In addition, a reactive group-containing prepolymer (α) and a polymer that does not react with the curing agent (β) during reaction of the reactive group-containing prepolymer (α) with the curing agent (β) [so-called dead polymer] It can also be contained. In this case, (b) is a mixture of a resin obtained by reacting the reactive group-containing prepolymer (α) and the curing agent (β) and an unreacted resin.

  The elongation and / or cross-linking reaction time is selected depending on the reactivity of the prepolymer (α) and the combination of the reactive groups and the curing agent (β), but is usually 10 minutes to 40 hours, preferably 30 minutes to 24 hours. The reaction temperature is usually 0 to 150 ° C., preferably 50 to 120 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate in the case of reaction of an isocyanate and an active hydrogen compound.

<Microchannel (M)>
A microchannel emulsification device is a device having a structure in which a dispersed phase and a continuous phase are separated by a partition having a through hole (flow channel) and the dispersed phase is pushed into the continuous phase through the through hole (flow channel). For example, a well-known thing (for example, the said patent document 2 is mentioned) can be used, without being specifically limited.
When the microchannel is formed by a photolithography technique, the etching method may be either wet etching or dry etching, but dry etching is preferable from the viewpoint of dimensional accuracy of the flow path.
The material of the substrate for forming the microchannel is not particularly limited, but is preferably one that does not dissolve or swell in the precursor (b0) of the resin (b) described later or a solvent, such as inorganic glass, silicon, and stainless steel. It is done. The microchannel surface preferably has good affinity with the continuous phase. For example, when the continuous phase is composed of water, the microchannel surface is preferably hydrophilic. For this reason, the surface of the microchannel may be chemically treated, for example, an organic substance or an inorganic substance having a functional group having an affinity for the continuous phase (CP) (for example, a hydrophilic group when the continuous phase is water). Methods such as coating, vapor deposition, sputtering, and CVD can be used.
As a method for forming a microchannel, a groove serving as a flow path is formed on a substrate by photolithography technology, and this is combined with a flat plate such as glass, or a channel is formed on the substrate by photolithography technology. Examples thereof include a method of forming a through hole. The size of the cross section of the channel of the microchannel is preferably set as appropriate according to the target particle size of the resin particles (B). For example, when obtaining (B) of 5 μm, 1 to 10 μm, preferably 2 to 6 μm, When it is desired to obtain (B) of 30 μm, the thickness is 10 to 50 μm, preferably 15 to 40 μm. The shape of the cross section of the channel is not particularly limited, and may be a circle, an ellipse, a triangle, a square, a rectangle, or the like. Among these, an oval shape and a rectangular shape are preferable. The distance between the two flow paths is preferably L to 15 × L, more preferably 2 × L to 10 × L, where (L) is the longest side of the cross section of the flow path. When it is L or less, the resin particles (B) generated from the microchannels can be easily combined. Moreover, productivity of resin particle (B) will worsen that it is 10xL or more.

<Formation of resin particles (B)>
By dispersing the dispersed phase (DP) in the continuous phase (CP) through the microchannel (M), particles (B0) composed of the precursor (b0) or particles (B0 ′) composed of the solvent solution thereof. In the case of particles (B0 ′), the solvent is further removed to obtain a dispersion of resin particles (B) made of resin (b).

The pressure (absolute pressure) of the dispersed phase (DP) is preferably controlled as long as particles can be formed, and specifically 0.1 kPa or less is preferable.
The volume flow ratio of the dispersed phase (DP) and the continuous phase (CP) is preferably 1:99 to 70:30, more preferably 10:90 to 65:35, and even more preferably 20:80 to 60:40. . When the volume flow ratio of (DP) and (CP) is within this range, the generation of waste liquid is small and the productivity of the resin particles (B) is also high. The flow rate and flow rate ratio of (DP) and (CP) are preferably controlled as appropriate within the range in which the particle size distribution does not deteriorate according to the target particle size of the resin particles (B).

  The continuous phase (CP) may contain a dispersing agent such as a surfactant (S) and a polymer surfactant (T), a plasticizer (V) and the like. The viscosity of (CP) is preferably 1 to 1,000 mPa · s (measured by a B-type viscometer, measurement temperature 25 ° C.), more preferably 5 to 500 mPa · s from the viewpoint of particle size uniformity. The viscosity of the dispersed phase (DP) is preferably 1 to 5000 mPa · s (measured value by a B-type viscometer, measurement temperature 25 ° C.), more preferably 10 to 1000 mPa · s, from the viewpoint of particle size uniformity. When the viscosity of (DP) is high, it is preferable to mix with the above-mentioned solvent and plasticizer (V) or to reduce the viscosity to the above preferred range by increasing the temperature. The viscosity ratio between the continuous phase (CP) and the dispersed phase (DP) is preferably set as appropriate according to the target particle size of the resin particles (B).

A preferable range of the temperature of the dispersed phase (DP) is 5 to 98 ° C, more preferably 10 to 60 ° C. Generally, when the viscosity of the dispersed phase (DP) is high, it is desirable to set the temperature high in order to reduce the viscosity.
The preferable range of the temperature of the continuous phase (CP) is 5 to 98 ° C, more preferably 10 to 60 ° C.
The difference between the temperature of the dispersed phase (DP) and the temperature of the continuous phase (CP) is not particularly limited, but a smaller one is preferable.

  As the surfactant (S), anionic surfactant (S-1), cationic surfactant (S-2), amphoteric surfactant (S-3), nonionic surfactant (S-4) and the like. Is mentioned. The surfactant (S) may be a combination of two or more surfactants.

Examples of the anionic surfactant (S-1) include carboxylic acid or a salt thereof, a sulfate ester salt, a salt of carboxymethylated product, a sulfonate salt, and a phosphate ester salt.
Examples of the cationic surfactant (S-2) include a quaternary ammonium salt type and an amine salt type.
The amphoteric surfactant (S-3) used in the present invention includes a carboxylate type amphoteric surfactant, a sulfate ester type amphoteric surfactant, a sulfonate type amphoteric surfactant, and a phosphate ester type amphoteric interface. Examples of the surfactant include amphoteric surfactants and amino acid-type amphoteric surfactants and betaine-type amphoteric surfactants.
Examples of the nonionic surfactant (S-4) include alkylene oxide addition type nonionic surfactants and polyvalent alcohol type nonionic surfactants.

  Examples of the polymeric active agent (T) include cellulose compounds (for example, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxyethyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose and saponified products thereof), gelatin, starch, dextrin, gum arabic, Chitin, chitosan, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, polyethyleneimine, polyacrylamide, acrylic acid (salt) -containing polymer (sodium polyacrylate, potassium polyacrylate, ammonium polyacrylate, sodium hydroxide part of polyacrylic acid Neutralized product, sodium acrylate-acrylic acid ester copolymer), sodium hydroxide of styrene-maleic anhydride copolymer (Partial) neutralization product, water-soluble polyurethane (polyethylene glycol, reaction products of polycaprolactone diol with polyisocyanate and the like) and the like.

The plasticizer (V) may be added to the continuous phase (CP) or the dispersed phase (DP) as necessary during emulsification dispersion. As a plasticizer (V), it is not limited at all, The following are illustrated.
(V1) Phthalates [dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, diisodecyl phthalate, etc.];
(V2) aliphatic dibasic acid ester [di-2-ethylhexyl adipate, 2-ethylhexyl sebacate, etc.];
(V3) trimellitic acid ester [tri-2-ethylhexyl trimellitic acid, trioctyl trimellitic acid, etc.];
(V4) Phosphate ester [triethyl phosphate, tri-2-ethylhexyl phosphate, tricresyl phosphate, etc.];
(V5) fatty acid ester [butyl oleate and the like];
(V6) and a mixture of two or more of these.

  The method for removing the solvent from the particles (B ′) is not particularly limited, and a known method can be used, and examples thereof include a method for removing the solvent under reduced pressure using an evaporator or the like. When removing the solvent by raising the temperature, it is preferable to set the temperature appropriately so that the resin particles (B) do not coalesce.

<Media removal method>
As a method of removing the medium from the dispersion of the resin particles (B), (WA1): a method of drying the dispersion of the resin particles (B) under reduced pressure or normal pressure, (WA2): a centrifuge, a spatula filter Examples include a method of solid-liquid separation using a filter press and the like, and drying the obtained powder, (WA3): a method of freezing and drying a dispersion of resin particles (B) (so-called freeze drying), and the like. In the case where the dispersion of the resin particles (B) contains a solvent capable of dissolving or swelling the resin particles (B), first, after the solvent is almost completely removed by the method (WA1), (WA1) to (WA3) It is preferable to remove the medium by any method. When it is not desired that impurities such as a surfactant remain in the resin particles (B), the slurry obtained in (WA2) is dispersed again in a medium not containing impurities, and the operation of performing (WA2) again is repeated. Thus, it is preferable to clean the impurities. In the above (WA1) and (WA2), when the obtained powder is dried, it can be performed using a known facility such as a fluidized bed dryer, a vacuum dryer, or a circulating dryer. Moreover, it can classify | classify using a wind classifier etc. as needed, and can also be set as predetermined particle size distribution. The drying temperature is preferably set as appropriate so that the resin particles (B) do not coalesce. Specifically, it is preferable to set the temperature 10 to 20 ° C. lower than the glass transition temperature of the resin particles (B).

<Resin particles (B)>
The volume average particle diameter of the resin particles (B) is preferably 0.1 to 1000 μm, more preferably 1 to 500 μm, and particularly preferably 5 to 300 μm from the viewpoint of industrial utility value.
The particle size uniformity of the resin particles (B) is expressed by the variation coefficient of the volume-based particle size distribution of the resin particles (B) and the volume average particle size of the resin particles (B) / number average particle size of the resin particles (B). Can be evaluated by value.
From the viewpoint of particle size uniformity, the variation coefficient of the volume-based particle size distribution of the resin particles (B) is preferably 0.1 to 10%, more preferably 0.1 to 9%, and 0.1 to 8%. Particularly preferred. The volume average particle diameter of the resin particles (B) / number average particle diameter of the resin particles (B) is preferably 1.4 or less, and more preferably 1.0 to 1.2. . The volume average particle diameter and the number average particle diameter can be simultaneously measured with Multitizer III (manufactured by Coulter).

  The shape of the resin particles (B) is preferably spherical from the viewpoint of powder fluidity, melt leveling properties and the like. In (B), Wadell's practical sphericity is preferably 0.85 to 1.00. The Wadell practical sphericity is obtained from a ratio of a diameter of a circle having an area equal to the projected area of the particle and a diameter of a circle having a minimum area circumscribing the projected image of the particle. The projected image of the particles can be taken with, for example, a scanning electron microscope (SEM).

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following description, “parts” represents parts by weight and “%” represents% by weight.

  In the following examples, a commercially available crossflow type microchannel emulsifier (Eptec Corp.) was used (channel type: MS310). The conceptual diagram of a microchannel is as FIG.

Production Example 1
A reaction vessel equipped with a stir bar and a thermometer was charged with 787 parts of polycaprolactone diol (molecular weight 2,000) and 800 parts of polyether diol (molecular weight 4,000, EO content 50% by weight, PO content 50% by weight), Dehydrated under reduced pressure at 120 ° C. The water content after dehydration was 0.05%. Next, 55.5 parts of hexamethylene diisocyanate (hereinafter referred to as HDI), 65.5 parts of dicyclohexylmethane-4,4′-diisocyanate (hereinafter referred to as hydrogenated MDI) and 0.6 part of dibutyltin dilaurate were added. The reaction was carried out at 80 ° C. for 5 hours. The obtained product is designated as [Water-soluble polymer T1]. 1 part of [Water-soluble polymer T1] and 107 parts of water were mixed and stirred to obtain a milky white liquid. This is designated as [continuous phase 1].

Production Example 2
784 parts of water and 80 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”, manufactured by Sanyo Chemical Industries) were mixed and stirred to obtain a milky white liquid. This is designated as [continuous phase 2].

Production Example 3
[Continuous phase 1] 108 parts and 8 parts of ethylenediamine were mixed and stirred to obtain a milky white liquid. This is designated as [continuous phase 3].

Production Example 4
Into a reaction vessel equipped with a stir bar and a thermometer, 2,000 parts of polycaprolactone diol having a hydroxyl number of 56 ["Placcel L220AL", manufactured by Daicel Chemical Industries, Ltd.] was charged and heated to 110 ° C under a reduced pressure of 3 mmHg. Then, dehydration was performed for 1 hour. Subsequently, 457 parts of isophorone diisocyanate (hereinafter referred to as IPDI) was added and reacted at 110 ° C. for 10 hours to obtain a urethane prepolymer having an isocyanate group at the terminal. The free isocyanate content of the urethane prepolymer was 3.6%. This is designated as [Prepolymer 1].

Production Example 5
In a reaction vessel equipped with a stir bar and a thermometer, 50 parts of ethylenediamine and 50 parts of MIBK were charged and reacted at 50 ° C. for 5 hours. Let the obtained ketimine compound be [curing agent 1].

Production Example 6
In a reaction vessel equipped with a stirrer and dehydrator, 681 parts of bisphenol A / EO 2 mol adduct, 81 parts of bisphenol A / PO 2 mol adduct, 275 parts of terephthalic acid, 7 parts of adipic acid, 22 parts of trimellitic anhydride, dibutyl 2 parts of tin oxide was added, and after 5 hours of dehydration reaction at normal pressure and 230 ° C., the dehydration reaction was performed for 5 hours under a reduced pressure of 3 mmHg to obtain [Polyester 1]. [Polyester 1] had a Tg of 54 ° C., a number average molecular weight of 2200, a weight average molecular weight of 9500, an acid value of 0.8, and a hydroxyl value of 53.

Production Example 7
In an autoclave, 407 parts of [Polyester 1] obtained in Production Example 6, 108 parts of isophorone diisocyanate, and 485 parts of ethyl acetate are added and reacted in a sealed state at 100 ° C. for 5 hours. A solution of polymer 2 [prepolymer solution 2] was obtained. [Prepolymer solution 2] had an NCO content of 1.7%.

Example 1
In a beaker, 150 parts of [Prepolymer 1] and 6 parts of [Curing Agent 1] were mixed to prepare Dispersed Phase 1. In the microchannel emulsifier of FIG. 1, [continuous phase 1] was flowed at 25 mg / hr as a continuous phase, and [dispersed phase 1] was flowed at 5 mg / hr as a dispersed phase. The liquid of dispersed phase 1 was discharged into the flow of [continuous phase 1] to obtain a dispersion of resin particles. [Curing agent 1] became ethylenediamine in water, and resin particles were formed by the extension reaction of [prepolymer 1] with ethylenediamine.
The dispersion was put into a reaction vessel equipped with a stirring bar and a thermometer, and reacted at 50 ° C. for 10 hours to obtain an aqueous dispersion (F10). Next, 1 part of an anti-blocking agent [“Syloid 978”, manufactured by Fuji Devison Chemical Co., Ltd.] and 0.5 part of a light-resistant stabilizer [“DIC-TBS”, manufactured by Dainippon Ink & Chemicals, Inc.] were added, and the mixture was filtered and circulated using a centrifuge. The resin particles (F1) were obtained by drying at 50 ° C. with an air dryer.

Example 2
In Example 1, an aqueous dispersion (F20) was obtained in the same manner as in Example 1 except that [Continuous phase 2] was used instead of [Continuous phase 1], and then filtered and dried to obtain resin particles ( F2) was obtained.

Example 3
[Dispersed phase 2] was prepared by placing 150 parts of [Prepolymer solution 2] in a beaker. In the microchannel emulsification apparatus of FIG. 1, [Continuous phase 1] is flowed at 25 mg / hr, and [Dispersed phase 2] is flowed at 5 mg / hr, and the liquid of disperse phase 2 is discharged into the flow of [Continuous phase 1]. A dispersion of resin particles was obtained. Resin particles were formed by extension reaction of [prepolymer 2] with water in [continuous phase 1].
The dispersion was put into an evaporator, and after removing the solvent for 30 minutes at a temperature of 50 ° C. and a pressure of 50 Torr, a reaction was performed at a temperature of 50 ° C. for 10 hours to obtain an aqueous dispersion (F30). Subsequently, filtration and drying were performed to obtain resin particles (F3).

Example 4
[Dispersed phase 2] was prepared by placing 150 parts of [Prepolymer solution 2] in a beaker. In the microchannel emulsifier of FIG. 1, [Continuous phase 1] is flowed at 25 mg / hr, [Dispersed phase 2] is flowed at 5 mg / hr, and the resulting dispersion is taken out every 10 minutes while maintaining the liquid temperature at 30 ° C. After adding 40 parts of ethylenediamine to 360 parts of the dispersion and stirring for 3 minutes, it was put into an evaporator, and after removing the solvent for 30 minutes at a temperature of 50 ° C. and a pressure of 50 Torr, the reaction was carried out at a temperature of 50 ° C. for 10 hours to obtain an aqueous dispersion. A body (F40) was obtained. Subsequently, filtration and drying were performed to obtain resin particles (F4).

Example 5
In Example 3, an aqueous dispersion (F50) was obtained in the same manner as in Example 3, except that [Continuous phase 3] was used instead of [Continuous phase 1]. Resin particles were formed by extension reaction of [Prepolymer 2] with ethylenediamine in [Continuous phase 3].
Subsequently, filtration and drying were performed to obtain resin particles (F5).

Comparative Example 1
Dissolving resin suspension method (for example, see Patent Document 1)
In a beaker, 150 parts of [Prepolymer 1] and 6 parts of [Curing Agent 1] are mixed, 708 parts of [Continuous Phase 1] are added, and an ultradisperser (manufactured by Yamato Kagaku) is used at room temperature. The mixture was mixed at a rotation speed of 9,000 rpm for 10 seconds to obtain a dispersion. The dispersion was put into an evaporator, and after removing the solvent for 30 minutes at a temperature of 50 ° C. and a pressure of 50 Torr, a reaction was performed at a temperature of 50 ° C. for 10 hours to obtain an aqueous dispersion (G10). Subsequently, filtration and drying were performed to obtain resin particles (G1).

Comparative Example 2
A method in which a vinyl monomer is dispersed in a continuous phase through a microchannel and radically polymerized (see, for example, Patent Document 2)
In Example 1, instead of [Dispersed Phase 1], 150 parts of divinylbenzene and 1 part of benzoyl peroxide were placed in a beaker to prepare [Dispersed Phase 3]. In the microchannel emulsifier of FIG. 1, [Continuous phase 2] was flowed at 25 mg / hr and [Dispersed phase 3] was flowed at 5 mg / hr to obtain a dispersion as in Example 1. The dispersion was put into an evaporator, and after removing the solvent for 30 minutes at a temperature of 50 ° C. and a pressure of 50 Torr, a reaction was performed at a temperature of 50 ° C. for 10 hours to obtain an aqueous dispersion (G20). Subsequently, filtration and drying were performed to obtain resin particles (G2).

Example of measuring physical properties Resin particles (F1) to (F5), (G1), and (G2) obtained in Examples 1 to 5 and Comparative Examples 1 and 2 are dispersed in water to obtain a multiple particle size distribution and volume average particle size. Measured with Sizer III (Coulter).
Table 1 shows the volume average particle diameter of the resin particles (B) and the coefficient of variation of the volume-based particle size distribution of the resin particles (B). Here, the coefficient of variation is a value calculated from a calculation formula of (standard deviation / volume average particle diameter × 100).
Table 1 shows the dispersed phase viscosity and continuous phase viscosity. The measurement was performed at 25 ° C. using a Brookfield type (B type) viscometer manufactured by Toki Sangyo Co., Ltd.

  Resin dispersions and resin particles obtained from the production method of the present invention include toners used for electrophotography, electrostatic recording, electrostatic printing, etc., spacers for producing electronic components such as slush molding resins, powder paints, and liquid crystals, It is extremely useful as a resin particle useful for standard particles for electronic measuring instruments, particles for electronic paper, various hot melt adhesives, and other molding materials.

Microchannel substrate

Enlarged view of CNL

Explanation of symbols

DP: disperse phase CP: continuous phase X: dispersion E of resin particles (B) E1: dispersion phase inlet E2: continuous phase inlet E3: dispersion outlet of resin particles (B)

Claims (9)

  The resin (b) precursor (b0) or a dispersed phase (DP) composed of a solvent solution thereof is dispersed in the continuous phase (CP) through the microchannel (M), thereby forming the precursor (b0). Resin (b) is formed by forming particles (B0 ') or particles (B0') comprising a solvent solution thereof, and further subjecting the particles (B0 ') to a polymerization reaction, and in the case of particles (B0'), further removing the solvent. A method for producing resin particles, comprising obtaining a dispersion of resin particles (B) comprising:   The method for producing resin particles according to claim 1, wherein the resin particles (B) are obtained by removing the medium from the dispersion of the resin particles (B).   The method for producing resin particles according to claim 1 or 2, wherein the precursor (b0) is a mixture containing a reactive group-containing prepolymer (α) and a curing agent (β).   The precursor (b0) is a reactive group-containing prepolymer (α), and the particles (B0) consisting of the precursor (b0) in the continuous phase (CP) or the particles (B0 ′) consisting of the solvent solution thereof and the curing agent The method for producing resin particles according to any one of claims 1 to 3, wherein (β) is polymerized.   The method for producing resin particles according to any one of claims 1 to 4, wherein the resin (b) is at least one resin selected from the group consisting of a polyurethane resin, an epoxy resin, a polyamide resin, and a polyester resin.   The method for producing resin particles according to any one of claims 1 to 5, wherein the precursor (b0) has at least one reactive group selected from the group consisting of an isocyanate group, a blocked isocyanate group, and an epoxy group.   The method for producing resin particles according to any one of claims 1 to 6, wherein the curing agent (β) is an active hydrogen group-containing compound or a compound obtained by blocking an active hydrogen group-containing compound.   The method for producing resin particles according to any one of claims 1 to 7, wherein the continuous phase (CP) further contains a dispersant. The method for producing resin particles according to any one of claims 1 to 8, wherein the coefficient of variation of the particle size distribution of the resin particles is 0.1 to 10%.

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