JPH04164925A - Resin particle and its production - Google Patents

Abstract

PURPOSE:To obtain resin particles having a sharp particle diameter distribution and being useful as a matting agent, an antiblocking agent, a carrier for medicines or the like by using resin particles mainly consisting of an ionic group-containing resin, wherein the properties of the particles are specified. CONSTITUTION:Resin particles mainly consisting of an ionic group-containing resin (e.g. a copolyester resin comprising an acid component comprising terephthalic acid, isophthalic acid or trimellitic acid and a glycol component comprising ethylene glycol or neopentyl glycol), wherein the mean particle diameter D is 1.0-100mum, the content of particles of diameters in the range of 0.5D-2.0D is 70wt.% or above based on all the particles, and the content of particles of sphericities (minor diameter/major diameter ratio) of 0.7 or above is 70% or above in terms of a number-average value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to resin particles. More specifically, it relates to resin particles that are widely used as matting agents, anti-blocking materials, carriers for chromatography, carriers for pharmaceuticals, powder coatings, gap adjustment materials, toners for electrophotography, cosmetics, etc. It is.

(Prior Art) As resin particles conventionally used for such uses, resin particles produced by a "polymerization granulation method" can be exemplified. Polymerization granulation methods can be broadly classified into emulsion polymerization methods, suspension polymerization methods, seed polymerization methods, and dispersion polymerization methods.

- Emulsilon polymerization method Emulsion polymerization method is a method in which resin particles are obtained by polymerizing in water in micelles of polymerizable monomers stabilized with a surfactant.

In the emulsion polymerization method, particles having a sharp particle size distribution can be obtained. However, since the particle size is determined by the size of micelles that can exist stably, the particle size is limited to a range of about 0.01 to 0.5 μm, and particles with a particle size of about 1 μm or more are obtained. That is impossible. Furthermore, since the surfactant essential for stabilizing micelles remains on the surface of the prepared particles, the range of use of the obtained resin particles is limited.

- Suspension polymerization method Suspension polymerization method is a method for obtaining particles by polymerizing polymerizable monomers in a suspension system obtained by mechanically stirring water and polymerizable monomers.

In suspension polymerization, polymerization in a stable system is not an option. Furthermore, since the particle size depends on mechanical stirring, it is difficult to obtain fine polymer particles with a uniform particle size distribution. Therefore, in suspension polymerization, a suspension stabilizer is used to prevent coalescence of particles and stabilize polymerization. Suspension stabilizers generally include sparingly soluble inorganic compounds such as sparingly soluble salts such as barium sulfate, calcium sulfate, magnesium carbonate, barium carbonate, calcium carbonate, calcium phosphate, silica, calcia, magnesia,
Metal oxides such as titanium oxide, minerals such as diatomaceous earth, talc, clay, kaolin, and mixtures thereof, or water-soluble mixtures such as polyvinyl alcohol, gelatin,
Starch etc. are used.

In fact, even when these suspension stabilizers are used,
The particle size range of particles obtained by the suspension polymerization method is approximately several tens of micrometers or more, and the particle size distribution is also broad, so operations such as classification are required after polymerization.

-Seed polymerization method Seed polymerization method is a polymerization method proposed to solve these problems. The seed polymerization method is a method in which particles obtained by other methods are used as seed particles, the seed particles are swollen with a solvent and a polymerizable monomer, and the swollen seed particles are polymerized to grow larger. be.

In the seed polymerization method, in principle, particles with a sharp particle size distribution can be obtained by selecting appropriate seed particles, and the particle size is determined by the amount of the seed particles and the polymerizable monomer. It can be controlled by the swelling rate with the body.

The seed polymerization method originally uses particles with a particle size between the particle size range of 0.01 to 0.5 μm obtained by the emulsion polymerization method and the particle size range of several tens of μm or more obtained by the suspension polymerization method. It was devised for manufacturing. Therefore, as a practical matter, particles that can be used as seed particles in industrial seed polymerization are limited to particles obtained by emulsion polymerization, that is, vinyl polymer particles, and the particle distribution is not that sharp. I can't get it.

It is difficult to swell vinyl polymer particles with polymerizable monomers. The swelling rate is determined by the interaction between the polymer constituting the seed particles and the monomer used for swelling, and the balance between the interfacial tension of the swollen particles, etc.
In reality, the limit is about 2 to 10 times at most.

In other words, the swelling ratio cannot be made extremely large, and -
There is naturally a limit to the particle size range that can be grown at once. Increasing the particle size by 10 times corresponds to increasing the volume by 1000 times, so in order to achieve this by seed polymerization, it is necessary to repeat seed polymerization.

- Two-stage swelling seed polymerization method The two-stage swelling seed polymerization method is a method devised to increase the swelling rate of seed particles. In the two-step swelling seed polymerization method, seed particles are first swollen with an oligomer or a poorly water-soluble low molecular weight substance (swelling agent), and then swelled with a polymerizable monomer. This method can increase the swelling rate of seed particles by several thousand times. However, since swelling agents remain in the particles obtained by the two-step swelling seed polymerization method, a step to remove them is essential, and the particles tend to have defects in sphericity.

Although the seed polymerization method is an excellent method in the sense of producing micron-order resin particles having a sharp particle size distribution, the above-mentioned problems make it difficult to commercialize the seed polymerization method.

・Dispersion polymerization method In the dispersion polymerization method, polymerizable monomers, initiators, and stabilizers are dissolved in an organic solvent to initiate polymerization, and the oligomer aggregates generated in the initial stage are used as particle nuclei in the organic solvent. This is a method of growing particles of insoluble polymers.

Although the dispersion polymerization method is an excellent method for producing micron-order resin particles with a sharp particle size distribution, it is difficult to mass produce because it uses an organic solvent as a medium, and it is difficult to obtain truly spherical particles. This method cannot be used as an industrial method for producing resin particles.

(Problems to be Solved by the Invention) As described above, in the emulsion 17 polymerization method and the suspension polymerization method, the particle size range of resin particles is limited and only resin particles with a broad particle size distribution are used. can't get it. In the seed polymerization method and the dispersion polymerization method, it is possible to obtain resin particles having a sharp particle size distribution.

However, these are difficult to mass produce, and it is virtually impossible to produce truly spherical resin particles at low cost.

(Means for Solving the Problems) In view of the above situation, the present inventors have developed resin particles having a sharp particle size distribution and an arbitrary particle size, and manufacturing that enables industrial production of the resin particles. As a result of intensive research to find a method, they arrived at the next invention.

That is, the present invention has an ionic group-containing resin as a main component, and has an average particle size in the range of 1.0 to 100 μm,
Resin particles characterized in that particles falling within the range of 0.5D to 2.0D account for 70% by weight or more of the total, and particles with a sphericity of 0°7 or more account for 70% or more of the total. ,
The ionic group-containing resin is stably microdispersed in an aqueous medium, and the microdispersed particles are plasticized. Resin particles characterized by breaking the stable state of micro-dispersed particles in a medium and causing the micro-dispersed particles to coalesce by changing the amount of ions (which have a function) under uniformly controlled conditions. This is a manufacturing method.

In the present invention, the ionic groups contained in the resin, which is the main component, include anionic groups such as carboxyl groups, sulfonic acid groups, sulfuric acid groups, phosphoric acid groups, hydroxyl groups, or their salts (hydrogen salts, metal salts), or a cationic group such as a primary to tertiary amine group, preferably a carboxyl group, an ammonium carboxylic acid base, a sulfonic acid group, or an alkali metal sulfonic acid base.

The form containing an ionic group is not particularly limited to this, but methods include mixing a compound containing an ionic group with a resin, or chemically bonding a compound containing an ionic group to a resin. Examples include a method using a resin having an ionic group in the molecule. In the present invention, it is preferable to use a resin obtained by copolymerizing or graft polymerizing a component containing an ionic group.

The content of ionic groups is approximately 20% for condensation polymers.
-1000 milliequivalents/1000100O range, preferably 50 to 500 milliequivalents/1000g.

These ionic groups are essential for forming an aqueous microdispersion of resin in the method for producing resin particles described below.

The resin used in the present invention is not particularly limited, and may include vinyl resins, polycondensation resins such as polyesters, polyamides, polyimides, polypeptides, and polyamino acids, polyurethanes, and polyureas. Natural polymers such as cellulose and chitin, or derivatives thereof (for example, chitin/chitosan resins, polysaccharide derivative resins, glucomannan resins)-based resins can be used.

In the present invention, polycondensation resins can be preferably used. More preferably, a polyester resin or a polyurethane resin can be used.

The resin serving as the main component preferably has a glass transition temperature of 40°C or higher, more preferably 60°C or higher. The softening temperature of the resin, which is the main component, is 8
The temperature is preferably in the range of 0 to 150°C.

Examples of polyester resins include saturated polyester resins,
Any unsaturated polyester resin can be used. The polyester resin in the present invention specifically consists of a dicarboxylic acid resin and a glycol component.

Examples of the dicarboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, and 1,5-naphthalic acid, and aromatic oxycarboxylic acids such as p-oxybenzoic acid and p-(hydroxyethoxy)benzoic acid. , aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, unsaturated aliphatic acids such as fumaric acid, maleic acid, itaconic acid, hexahydrophthalic acid, tetrahydrophthalic acid, and Alicyclic dicarboxylic acids and the like can be used.

As the acid component, a small amount of tri- and tetracarboxylic acids such as trimellitic acid, trimesic acid, and pyromellitic acid may be included if necessary.

Examples of glycol components include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, and dipropylene. glycol, 2
, 2,4-trimethyl-1,3-bentanediol, 1
．． 4-Cyclohexane dimetatool, spiroglycol, 1゜4-phenylene glycol, ethylene oxide adduct of 1.4-phenylene glycol, diol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide adduct of bisphenol A Also usable are propylene oxide adducts, ethylene oxide adducts of hydrogenated bisphenol A, alicyclic diols and propylene oxide adducts, and the like.

In addition to these, small amounts of triols and tetraols such as trimethylolethane, trimethylolpropane, glycerin, and pentanylthritol may be included, if necessary. The polyester polyol may also include lactone-based polyester polyols obtained by ring-opening polymerization of lactones such as ε-caprolactone.

Preferred polyesters in the present invention are those mainly using benzene dicarboxylic acid as the acid component. In particular, when dye coloring is applied to the particles, it is preferable to use a polyester resin containing 80 mo1% or more of terephthalic acid and isophthalic acid as acid components.

Preferred polyesters in the present invention are those using mainly aliphatic diols as the glycol component.

In the present invention, the preferred polyester mainly uses aliphatic diols as the glycol component, and contains aromatic diols in an amount not exceeding 20 o 1% of the glycol component.
It uses a ring group diol.

Examples of sulfonic acid metal base-containing compounds that can be copolymerized with condensation polymers such as polyester and polyurethane include sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2.7 dicarboxylic acid, 5( Examples include metal salts such as 4-sulfophenoxydiisophthalic acid. Examples of metal salts include L 11Na1
Examples include salts such as 1Mg1CalCusFe, and particularly preferred is Na salt.

When the condensation polymer is a polyester resin,
Preferably, 5-sodium sulfoisophthalic acid is used.

The resin particles shown in the present invention are made by adding an ionic group-containing resin that is stably micro-dispersed in an aqueous medium to the surface of the micro-dispersed particles and the micro-organisms present near the surface in a plasticized state. The amount of ions that have the function of stabilizing dispersed fine particles in an aqueous medium is
By means of reducing it under uniformly controlled conditions,
It can be obtained by disrupting the stable state of microdispersed particles in a medium and causing the microdispersed particles to coalesce. In the present invention, the term "aqueous microdispersion" refers to a state in which it is dispersed in water by forming stable micelles through the formation of an electric double layer. It means something.

The ionic group-containing resin can be plasticized by raising the temperature of the system above the glass transition temperature or softening temperature, or by adding a solvent that has the function of plasticizing the ionic group-containing resin to the ionic base. Examples include a method of incorporating into a resin.

In the present invention, preferably a method of plasticizing by controlling the temperature of the system can be used. As for the temperature range, a range from approximately the glass transition temperature to a temperature 50° C. higher than the glass transition temperature can be preferably used. More preferably, a temperature range up to 2-5° C. above the glass transition temperature can be used. In this case, if necessary, the system can also be placed under pressure. Further, a solvent or the like having a function of substantially lowering the glass transition humidity of the resin may be used in combination.

The solid content concentration of the aqueous microdispersion is approximately 5 to 60% by weight,
More preferably, the content is in the range of 15 to 40% by weight. If the solid content concentration is below the lower limit, the probability that microdispersed particles will meet each other decreases, so that coalescence and growth of particles may be difficult to occur.

Furthermore, if the upper limit of the solid content concentration is exceeded, it may become difficult to maintain the uniformity of the system.

As mentioned above, the "aqueous microdispersion" in the present invention
means a state in which dispersed particles are stably dispersed in water by forming an electric double layer on their surfaces.

Ions in a dissociated state are essential for the formation of an electric double layer, and the area where the electric double layer can exist, that is, the total surface area of the dispersed particles, depends on the absolute amount of ions forming the electric double layer. Therefore, if the amount of ions is reduced (changed) uniformly and under controlled conditions, the area of the surface of the stably existing vine particles will decrease, resulting in a "state with a smaller surface area," or " ``dispersed particles with large particle size''.

Coalescence of micro-dispersed particles is exactly this process, and plasticization of the polymer is an essential requirement in order for the aggregated micro-dispersed particles to become one new particle that is truly coalesced, rather than just a "powder aggregate". becomes.

The method of changing the amount of ions in the dispersion system of the present invention will be exemplified below.

As a specific method for producing the resin particles according to the present invention, a method of adding an electrolyte to an aqueous microdispersion of an ionic group-containing resin in a plasticized state can be mentioned.

The electrolyte in the present invention refers to a compound that ionically dissociates in water, and examples include water-soluble inorganic salts and salts of water-soluble polymers containing ionic groups. Preferably, alkali metal ions, alkaline earth metal ions, ammonium ions, halogen ions, sulfate ions, and salts of anionic bases and water-soluble polymers can be used.

The electrolyte is preferably supplied in the form of a relatively dilute aqueous solution while stirring the aqueous microdispersion, also for the purpose of maintaining uniformity within the system.

This method is based on the effect that the addition of electrolyte makes it difficult to maintain the electric double layer structure and excessively increases the absolute amount of ions in the system, thereby effectively reducing the amount of ions that participate in particle dispersion. be.

In the present invention, from a system in which electrolyte is added in advance to a concentration just before the stability of the microdispersion is impaired,
Means for removing water by evaporation, filtration, etc. to substantially increase the electrolyte concentration can also be used.

A specific method for manufacturing the resin particles according to the present invention is as follows: ``Into an aqueous microdispersion of an ionic group-containing resin in a plasticized state, a compound containing a counter ion to an ionic group contained in the resin is added. For example, "method of addition."

In this case, "counter ion" means an anion when the ionic group contained in the ionic group-containing resin is a cationic group,
When the ionic group contained in the resin is an anionic group, it means a cation.

This method can be preferably applied when the ionic group contained in the resin is an anionic group.

In the present invention, one of the methods for changing the absolute amount of ions forming the electric double layer on the surface of microdispersed particles under uniformly controlled conditions is to A method for performing pH scanning in a dispersion can be shown.

This method is based on the effect that the dissociation state of the ionic groups forming the electric double layer changes depending on 1) H. This method uses an aqueous microdispersion of a resin containing an ionic group whose dissociation state can be controlled by changing the pH, more specifically a resin containing a carboxyl group neutralized by ammonium ions, or a resin neutralized by carboxylic acids. This method is preferably applied when using a resin containing amino groups.

As a specific method for pH scanning, an acid or alkali may be added to the aqueous microdispersion, but it is more preferable to use a compound that newly generates an acid or alkali through reaction or thermal decomposition. can. Examples of such compounds include inorganic acid polymers that generate acids upon decomposition, such as triazine that generates acids when irradiated with light;
Examples include hydrogen carbonate that generates alkali. Further, compounds having ester bonds in their molecular chains undergo hydrolysis when the pH of the system is on the alkaline side, producing carboxylic acid and hydroxyl groups, and exhibiting the effect of lowering the pH of the system.

In special cases, these hydrolysis reactions can also be used as a pH scanning technique.

Examples of inorganic acid multimers or salts thereof include beroxonisulfuric acid, metal salts, alkali metal salts, alkaline earth metal salts, and ammonium salts of beroxonisulfuric acid. Among peroxonisulfates, alkali metal salts or ammonium salts can be particularly preferably used. Particularly preferred is ammonium belloxonisulfate.

Similarly, an alkali metal salt or an ammonium salt can be preferably used as a hydrogen carbonate. Particularly preferably, sodium hydrogen carbonate can be used.

The method for decomposing beroxonisulfate and hydrogen carbonate is not particularly limited.

Since these decompose naturally in an aqueous solution, the purpose can be achieved without special measures. however,
In order to promote the reaction, it is a preferable method to accelerate the decomposition by heating or the like.

A polymer (resin) having an ionic group forms stable micelles due to an electric double layer generated by the dissociation of the ionic group, thereby forming an aqueous microdispersion. If the dissociation state of the ionic group is changed from the dissociation side to the non-dissociation side by simultaneously scanning either the pH or the temperature, or both while keeping the entire system uniform,
The stable microdispersion state becomes slightly destabilized and a gradual agglomeration of particles occurs.

If the uniformity of the system (from a macro perspective) is maintained, particles will coalesce with equal probability, and the resulting particles will have an extremely sharp particle size distribution. Scanning the pH while maintaining the homogeneity of the system is relatively difficult using conventional methods such as dropping acid or alkali into the system and mixing and stirring.This method is effective in maintaining system uniformity. It is something that has characteristics.

As a specific method for obtaining the resin particles shown in the present invention,
A method for decomposing an inorganic acid multimer or a salt thereof in the presence of cations in an aqueous microdispersion of an ionic group-containing resin in a plasticized state.

That is, cations are allowed to exist when the above-mentioned inorganic acid multimer is decomposed. The cation has the function of sharpening the particle size distribution of the combined particles.

As the cation, ammonium ions are preferable, and ammonium, methylammonium, dimethylammonium, trimethylammonium, ethylammonium, diethylammonium, triethylammonium, etc. can be used. In addition to these, 2-aminoethanol, 2-N.

N-dimethylaminoethanol, 2-N,N-diethylaminoethanol, 2-N,N-dipropylamino(meth)ethanol, 2-N,t-butylaminoethanol, 2-(4-morpholino)-ethanol, and These (meth)acrylic acid esters, specifically 2-aminoethyl (meth)acrylate), 2-N,N-dimethylaminoethyl (meth)acrylate), 2-N,N-diethylaminoethyl (meth) ) acrylate, 2-N, N-dipropylaminoethyl (meth)acrylate, 2-N,
t-Butylaminoethyl (meth)acrylate, 2-(
4-morpholino)-ethyl (meth)acrylate, 2-
Vinylpyridine, 4-vinylpyridine, aminostyrene, etc. can be used.

In the present invention, reactive cations can be particularly preferably used. In this case, as the inorganic acid multimer decomposes, the cations polymerize and form a polyion complex, so particles are rapidly fused and granulated, making it possible to obtain particles with a very sharp particle size distribution. can.

As a specific method for obtaining the resin particles shown in the present invention,
A method for decomposing hydrogen carbonate in the presence of anions in an aqueous microdispersion of an ionic group-containing resin in a plasticized state.

Anions include formic acid, acetic acid, (meth)acrylic acid,
Compounds containing carboxyl groups or their salts such as itaconic acid, phlotonic acid, maleic acid, fumaric acid, phenolsulfonic acid, benzenesulfonic acid, styrenesulfonic acid, vinyltoluenesulfonic acid, vinylethylbenzenesulfonic acid, impropenylbenzenesulfonic acid , 2-
Chlorostyrene sulfonic acid, 2-methyl-4-chlorostyrene sulfonic acid, vinyloxybenzenesulfonic acid,
Compounds containing sulfonic acid groups or salts thereof, such as vinylsulfonic acid, (meth)allylsulfonic acid, sulfoethyl ester or sulfopropyl ester of (meth)acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, azide Phosphoxyethyl (meth)acrylate, azidophosphoxypropyl (meth)acrylate 3-
Compounds containing a phosphoric acid group or a salt thereof such as chloro-2-azidophosphoxypropyl methacrylate, bis(meth)acryloxyethyl phosphate, and vinyl phosphate can be used.

In the present invention, a water-soluble polymer can be made to exist in the aqueous microdispersion in advance within a range that does not impair its stability.

As the water-soluble polymer, a water-soluble polymer containing one or more ionic groups selected from a hydroxyl group, a sulfonic acid group, a sulfonate group, a carboxyl group, and a carboxylate group may be selected. preferable. In addition, the molecular weight of the water-soluble polymer is 1000 or more, preferably 3000 or more,
More preferably, it is 10,000 or more.

These water-soluble polymers softly wrap the vicinity of the microscopic resin particles dispersed in the aqueous microdispersion, so they have a buffering effect that substantially homogenizes the environment within the system (PUS electrolyte concentration, etc.). considered to be a thing.

In the present invention, the resin particles can be colored with a pigment if necessary. As the pigment, lake pigments, rhodamine pigments, quinacridone pigments, anthraquinone pigments, monoazo pigments, disazo pigments, phthalocyanine pigments, etc. can be used.

In particular, as the yellow pigment, anthraquinone pigments and disazo pigments are preferred, and disazo yellow pigments having benzidine as a basic skeleton are more preferred. Specifically, disazo yellow pigments having benzidine as a basic skeleton include C, 1, bigmen) iso-12, 13, 14
, 15, 1117, 83, 77, etc.

In particular, as magenta pigments, anthraquinone pigments and quinacridone pigments are preferred. Specific examples of the quinacridone pigment include C,1, Pigment Violet 19, C,1, Pigment Red 30.122, and the like.

In particular, phthalocyanine pigments are preferred as cyanine pigments. Specifically, the phthalocyanine pigment is C,1, Pigment Blue 15.15:1.15:2
．． 15:3.15:4.16.17.17:1,C,1
, Pigment Order Green 7.13.25.36.37,
etc. can be exemplified.

The pigment content is about 0.1 to 25% by weight.

Methods for dispersing the pigment into resin particles in a golden color are not particularly limited, but include a method of kneading the pigment into the resin in advance, or a method of dispersing the pigment in water when coalescing and growing fine particles in an aqueous dispersion. Examples include a method in which the particles are incorporated into the particles at the same time as the coalescence of the particles by allowing the particles to coexist as a body, and a method in which the particles are mechanically implanted into the particle surface after granulation.

In the present invention, the resin particles can be colored with a dye if necessary. As the dye, disperse dyes, vat dyes, metal-containing dyes, oil-soluble dyes, acid dyes, basic dyes, cationic dyes, metal-containing dyes, and reactive dyes can be used. Preferably, disperse dyes or cationic dyes can be used.

In the present invention, carbon black can be contained in the resin particles as necessary. As carbon black, thermal black, acetylene black, channel black, furnace black, lamp black, etc. can be used. Carbon black content is 0
．． It is about 1 to 25% by weight.

In the present invention, carbon black may be used alone or in combination as necessary. Further, other colorants such as pigments and dyes may be used in combination as necessary.

Carbon black may be adsorbed onto particles, for example.
It may be coated or mechanically driven into the particle surface, for example by a dry process, but it is most preferably contained in the particle in dispersed form.

Methods for producing particles containing carbon black in a dispersed form include a method in which carbon black is dispersed in a resin in advance and then made into particles;
Another example is a method in which an aqueous dispersion of carbon black is made to coexist during granulation so that it is incorporated into particles during coalescence and granulation of microparticles.

In the present invention, fine silica powder may be included in order to control the surface properties, fluidity, chargeability, etc. of the particles. These fine silica powders are preferably present at least in the surface layer of the toner or in the vicinity of the surface layer.

More specifically, it adheres to the surface layer of the polyester particles,
Alternatively, it is preferable that the polyester particles are coated with a surface layer or exist in the form of sticks half-buried in the surface of the polyester particles.

The fine silica powder preferably covers 25% or more, preferably 40% or more of the surface of the polyester particles, and the fine silica particles are preferably half-buried in the surface layer of the polyester particles.

Further, the silica fine particles are preferably contained in such a manner that the silica content within a depth range of 0.05D from the particle surface is 10% by weight or more, where D is the average particle diameter of the polyester particles. The fine silica powder used in the present invention preferably has an average particle size of 1 μm or less. Moreover, it is preferable that the shape is spherical. These fine silica powders can be adsorbed onto particles in a wet or dry manner, for example.
The backing can be treated by a method such as adsorption and then fixation.

In the present invention, a charge control agent may be used especially when it is necessary to control the triboelectric properties of the obtained resin particles. As the charge control agent, pigments, fine resin particles having an average particle size of 2 microns or less, and inorganic particles can be used.

Examples of pigment-type charge control agents that positively charge the toner through friction with carrier particles (carrier) include Ca1
Pigments with positive zeta potential such as titanates such as Ba, carbonates, alkoxylated amines, polyamide resins such as nylon, phthalocyanine blue, quinacridone red, azo metal complex green, etc., azine compounds, stearic acid modification Examples include azine compounds, oleic acid-modified azine compounds, azine pigments such as nigrosine, and quaternary ammonium salt compounds.

Examples of pigment-type charge control agents that impart a negative charge to the toner through friction with carrier particles (carrier) include pigments with negative zeta potential such as carbon black, halogenated phthalocyanine green, flavanstone yellow, and perylene red; Examples include metal-containing azo compounds such as copper, zinc, lead, and iron.

Examples of resin fine particles having an average particle size of 2 microns or less include fine particles of polyamide resin such as nylon, urethane resin, polymethyl methacrylate resin, and the like.

As the inorganic particles, fine powders of minerals such as talc, mica, kaolin, clay, etc., fine powders of metal oxides such as silica, titanium oxide, magnesia, calcia, alumina, etc. can be used.

These charge control agents are preferably present at least in the surface layer of the toner or in the vicinity of the surface layer. More specifically,
It is preferable that the polyester particles be present as a coating on the surface layer of the polyester particles or as being implanted into the surface. When the charge control agent is implanted into the surface, it is preferable that a portion of the charge control agent is exposed.

These charge control agents can be treated by, for example, adsorbing them onto particles in a wet or dry manner, or by adsorbing them and then fixing them.

In the present invention, the resin particles may be coated with a thermoplastic polymer different from the main component thereof in order to control the surface properties, fluidity, chargeability, etc. of the particles. The thermoplastic resin has a diameter of 0.0 from the surface, where the average particle diameter of the resin particles is D.
It is preferable that the content is 30% by weight or more in the range of 5D.

As the thermoplastic resin, polymers such as polyethylene resin, vinyl chloride resin, polypropylene resin, rubber, nylon resin, urethane resin, acrylic resin, polymethyl methacrylate resin, fluororesin, and silicone resin can be used.

Preferred resins in the present invention are urethane resins and resins containing polymethyl methacrylate as a main component, and more preferably resins containing polymethyl methacrylate as a main component.

The method for coating the surfaces of resin particles with these thermoplastic resins is not particularly limited, and any known existing treatment method can be used. These may be treated either wet or dry.

In the present invention, if it is necessary to impart magnetism to the resin particles, magnetic powder can be included in the resin particles. As the magnetic powder, iron, cobalt, nickel, an alloy mainly composed of these, or oxides such as ferrite and magnetite can be used. In particular, it is preferable to use oxide-based magnetic powder mainly composed of ferrite. These may be used alone or in combination of two or more. Further, these magnetic powders may be treated with a silane coupling agent, a titanate coupling agent, a phosphoric acid coupling agent, a surfactant, etc., if necessary. The content of magnetic powder is preferably 10 to 70% by weight, and 15% by weight.
-50% by weight is more preferred.

(Example) The present invention will be explained in more detail by referring to Examples below, but the present invention is not limited to these in any way. In addition, physical properties of resins and the like in Examples and Comparative Examples were measured by the following methods.

・Melting point, glass transition point A heating rate of 1 was measured using a differential scanning calorimeter (manufactured by Shimadzu Corporation).
Measurement was performed at 0°C/min.

・Softening point Measured according to JIS K2351.

・Number average molecular weight (vapor pressure method) It was measured using a molecular weight measuring device (Hitachi, Ltd. model).

In addition, the average particle diameter, particle size distribution, sphericity, and sphericity distribution of the particles were determined by image processing a scanning electron micrograph of the particles.

[Example 1] Production of polyester resin In an autoclave equipped with a thermometer and a stirrer, 96 parts by weight of dimethyl terephthalate, 97 parts by weight of dimethyl isophthalate, and ethylene glycol were added.
es weight g, neopentyl glycol
114 parts by weight and 0.1 parts by weight of tetrabutoxy titanate were charged and heated at 150 to 220°C for 180 minutes to perform a transesterification reaction. Next, after raising the temperature to 240° C., the pressure of the system was gradually reduced to 10 mmHg after 30 minutes, and the reaction was continued for 60 minutes. Thereafter, the inside of the autoclave was replaced with nitrogen gas to bring it to atmospheric pressure. The temperature was maintained at 200° C., 2.9 parts of trimellitic anhydride was added, and the reaction was carried out for 60 minutes to obtain a copolymerized polyester resin.

The molecular weight of the obtained copolymerized polyester resin was 2800,
The acid value was 0.14 equivalent/1000g. As a result of NMR analysis, the obtained polyester resin contained 49.2% terephthalic acid, 49.3% isophthalic acid, and 49.3% trimeric acid as acid components.
The glycol components were 50.0% ethylene glycol and 50.0% neopentyl glycol.

(2) Preparation of copolymerized polyester aqueous dispersion To 34 parts of the copolymerized polyester obtained, 10 parts of butyl cellosolve was added and dissolved at 110°C, and then cooled to 80°C. Furthermore, an ammonia aqueous solution of IN was added in an amount equal to the acid value of the copolymerized polyester, and the temperature was maintained at 80°C for 30 minutes.
After stirring for 0 minutes, 56 parts of water at 80°C was added to obtain an aqueous dispersion of copolyester. Furthermore, 1000 parts of the obtained aqueous ° dispersion was placed in a distillation flask, and the distillation temperature was 10
After distilling until it reaches 0°C, cool it and add 250 ml of deionized water.
A copolymerized polyester aqueous dispersion containing no butyl cellosolve was obtained.

(2) Production of polyester particles 834 parts by weight of the copolymerized polyester aqueous dispersion and 800 parts by weight of deionized water were placed in a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade and stirred. Next, 100 parts by weight of an aqueous solution containing 8.0 parts by weight of ammonium belloxonisulfate was added dropwise over 50 minutes, and the temperature was simultaneously raised to 70°C at a rate of 1°C/min. Cooled to . The pH of the bath before dropping ammonium belloxonisulfate was 10.
5. The pH after dropping and cooling was 5.8.

As a result, the copolymer with a particle size on the submicron order that was present in the aqueous copolyester dispersion grew into particles, and the average particle size was 5.7 μm1o, and the occupancy rate of particles with a particle size in the range of 5D to 2D Polyester particles were obtained having a weight of 95% and an occupancy rate of 98% (number) of particles having a sphericity of 0.7 or more.

[Example 2] ■Production of polyester resin In an autoclave equipped with a thermometer and a stirrer, 100 parts by weight of dimethyl terephthalate, 100 parts by weight of dimethyl isophthalate, and ethylene glycol were added.
68 parts by weight, neopentyl glycol
114 parts by weight, 2-dimethylaminomethyl, 2-methyl 1. 10 parts by weight of 3-propanediol and 0.1 part by weight of tetrabutoxy titanate were charged and heated at 150 to 220°C for 180 minutes to perform a transesterification reaction. Next, after raising the temperature to 240° C., the pressure of the system was gradually reduced to 10 mmHg after 30 minutes, and the reaction was continued for 60 minutes. Thereafter, the inside of the autoclave was replaced with nitrogen gas to bring the pressure to atmospheric pressure, thereby obtaining a copolymerized polyester resin.

The molecular weight of the obtained copolymerized polyester resin was 3200,
The acid value was 0.14 equivalent/1000g. As a result of NMR analysis, the obtained polyester resin (A1) contained 50.0% terephthalic acid, 50.0% isophthalic acid as acid components, 49.0% ethylene glycol, 49.0% neopentyl glycol, and 2-dimethylamino as glycol components. Methyl, 2-methyl 1.3 propanediol 2.0%.

■Production of copolymerized polyester aqueous dispersion To 34 parts of the copolymerized polyester obtained, 10 parts of butyl cellosolve was added and dissolved at 110°C, then cooled to 80°C, 56 parts of water at 80°C was added, and the copolymerized polyester was dissolved. An aqueous dispersion was obtained. Further, 1000 parts of the obtained aqueous dispersion was placed in a distillation flask, and after distillation was performed until the distillation temperature reached 100°C, it was cooled, and 250 parts of deionized water was added to form an aqueous dispersion of copolyester that does not contain butyl cellosolve. Obtained.

(2) Production of polyester particles 834 parts by weight of the copolymerized polyester aqueous dispersion was placed in a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade and stirred.

The pH of the bath was 5.9. Next, sodium bicarbonate 4
1000 parts by weight of an aqueous solution containing 0 parts by weight was added dropwise over 60 minutes, and at the same time the temperature was raised to 80°C at a temperature increase rate of 1°C/min. After being held at 80°C for 60 minutes, it was cooled to room temperature. The pH of the bath was 8.9. As a result, the particles of the copolymer with a particle size on the submicron order that existed in the copolymerized polyester aqueous dispersion grew, and the average particle size was 7.8.
Polyester particles were obtained in which the occupancy rate (weight) of particles having a particle diameter in the range of 10.5D to 2D µm was 94% (weight), and the occupancy rate (number) of particles having a sphericity of 0.7 or more was 97% (number).

[Example 3] In an autoclave equipped with a thermometer and a stirrer, 94 parts by weight of dimethyl terephthalate, 95 parts by weight of dimethyl inphthalate, and ethylene glycol were placed.
89 Weight g, neopentyl glycol
80 parts by weight and 0.1 part by weight of tetrabutoxy titanate were charged and heated at 120 to 230°C for 120 minutes to perform a transesterification reaction. Next, 7 g of 5-sodium sulfoisophthalic acid e was added, and the reaction was continued at 220 to 230°C for 60 minutes. After further heating to 250°C, the system pressure was reduced to 1 to 10 mmHg.
As a result of continuing the reaction for 60 minutes, a copolymerized polyester resin was obtained.

The molecular weight of the obtained copolymerized polyester resin was 2700,
The sulfonic acid metal base was 0.12 equivalent/1000g. The amount of sulfonic acid metal base was determined by measuring the sulfur concentration in the copolyester resin. In addition, as a result of NMR analysis, the composition of the copolymerized polyester resin was found to be as follows: as an acid component, terephthalic acid 4B, 5M0L%, isophthalic acid 49.0M0L%, 5-sodium sulfoisophthalic acid 2.5M0L%, as an alcohol component, ethylene glycol 61 .0M0L%, neopentyl glycol 39.0M0L%.

In a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade, 34 parts by weight of the obtained copolymerized polyester resin and 10 parts by weight of butyl cellosolve were dissolved at 110°C, and then heated to 80°C. 56 parts by weight of water was added to obtain an aqueous dispersion of copolyester.

In a four-necked 5-liter separable flask equipped with a thermometer, condenser, and stirring blade, 834 parts by weight of the copolymerized polyester aqueous dispersion, 35 parts by weight of deionized water, and
6.7 parts by weight of dimethylaminoethyl methacrylate was added and stirred. The pH of the bath was 11.5. Then,
The bath temperature was raised to 70°C, and 100 parts by weight of an aqueous solution containing 0.2 parts by weight of ammonium beroxonisulfate was added dropwise over 40 minutes. The pH of the bath was 5.8. The result is 0
As a result, the copolymer with a submicron-order particle size that was present in the copolymerized polyester aqueous dispersion grew into particles with an average particle size of 8.7 μm and a particle size in the range of 0.5D to 2D, where 1 diameter is D. Polyester particles having a particle occupancy rate of 94% by weight were obtained.

[Example 4] 208.5 parts by weight of the aqueous copolyester dispersion obtained in Example 1 (solid content 34 parts by weight) was placed in a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade. %) and the temperature was raised to 70°C while stirring. Next, 26 parts by weight of deionized water in which 3.0 parts by weight of sodium sulfate was dissolved was added dropwise over 40 minutes.
Stirring was continued at a constant temperature of 70° C. for minutes. As a result, the copolymer with a submicron-order particle size that existed in the copolymerized polyester aqueous dispersion grew into particles with an average particle size of 3.2 μm and a particle size in the range of 0.5D to 2D. Polyester particles were obtained in which the occupancy rate (weight) was 72%, and the occupancy rate (number) of particles with a sphericity of 0.7 or more was 98%.

[Example 5] 208.5 parts by weight of the aqueous copolyester dispersion obtained in Example 3 (solid content 34 parts by weight) was placed in a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade. %), and the same operation as in Example 4 was performed. As a result, the copolymer with a submicron-order particle size that was present in the copolymerized polyester aqueous dispersion grew into particles with an average particle size of 4.3+C'm)o, and a particle size in the range of 5D to 2D. Polyester particles were obtained in which the proportion (weight) of the particles was 78% and the proportion (number) of particles having a sphericity of 0.7 or more was 99% (number).

[Example 6] 270 parts by weight of the aqueous copolyester dispersion obtained in Example 3 (solid content: 34
wt%), Porin Sodium Lastyrene Sulfonate 8
parts by weight were added, and the temperature was raised to 70°C while stirring. Next, deionized water 26 in which 5.0 parts by weight of sodium sulfate was dissolved
parts by weight were added dropwise over 40 minutes, and then for an additional 180 minutes.
Stirring was continued while maintaining the temperature at 0°C. As a result, the copolymer with a submicron-order particle size that was present in the copolymerized polyester aqueous dispersion underwent particle growth, and the average particle size decreased to 5.
．． Polyester particles were obtained in which the occupancy rate (weight) of particles having a particle diameter in the range of 4 cm 10.5D to 2D was 88%, and the occupancy rate (number) of particles having a sphericity of 0.7 or more was 95% (number).

[Example 7] 834 parts by weight of the copolymerized polyester aqueous dispersion obtained in Example 1 and 100 parts by weight of deionized water were placed in a four-necked 1-liter separable flask equipped with a thermometer, condenser, and stirring blade. , and 5.6 parts by weight of dimethylaminoethyl methacrylate. The pH of the bath was 10.3. Next, the bath temperature was raised to 70°C, 100 parts by weight of an aqueous solution containing 0.2 parts by weight of ammonium beroxonisulfate was added dropwise over 30 minutes, and then the bath was heated at 70°C for another 20 minutes.
I kept it. The pH of the bath was 6.2. As a result, the particles of the copolymer with a submicron-order particle size that existed in the aqueous copolyester dispersion grew, and the average particle size decreased to 4.
．． Occupancy (weight) of particles with particle diameters ranging from 9 μm 10.5D to 2D.

Polyester particles having a sphericity of 94% and an occupancy rate of 92% (number of particles) of particles having a sphericity of 0.7 or more were obtained.

[Example 8] Adjustment of polyester polyol In an autoclave equipped with a thermometer and a stirrer, 392 parts by weight of dimethyl terephthalate, 392 parts by weight of dimethyl isophthalate, and ethylene glycol were added.
310 parts by weight, neopentyl glycol 520
Part by weight was charged and heated and stirred at 200°C for 360 minutes to react until the methanol distillate was 252 parts by weight.
Cool to 20°C, add 292 parts by weight of adipic acid,
The temperature was raised again to 200° C., and the reaction was carried out for 480 minutes to obtain a polyester polyol.

■Urethanization and preparation of polyurethane aqueous dispersion 100 parts by weight of the obtained polyester polyol was dehydrated at 120°C under reduced pressure, then cooled to 80°C, 100 parts by weight of methyl ethyl ketone was added, stirred and dissolved, and mixed in a tolyorange. 65.3 parts by weight of isocyanate and 17.7 parts by weight of 2,2-dimethylolpropionic acid as a chain extender were added, and the mixture was reacted at 70°C for 10 hours. After completion of reaction 4
After cooling to 0°C, 12.3 parts by weight of piperazine and 13.3 parts by weight of triethylamine were added for chain extension and neutralization, and then 500 parts by weight of water was added to obtain an aqueous dispersion of polyurethane.

■Production of polyurethane particles 800 parts by weight of the obtained aqueous polyurethane dispersion, 800 parts by weight of deionized water, and dimethylaminoethyl methacrylate were placed in a four-necked 5-liter separable flask equipped with a thermometer, condenser, and stirring blade. 25 parts by weight was added. The pH of the bath was 10.6. Next, the bath temperature was raised to 70°C, and 0.2 ammonium beloxonisulfate was added.
After dropping 100 parts by weight of an aqueous solution containing 100 parts by weight over 30 minutes, the temperature was maintained at 70°C for an additional 20 minutes. Bath 1)
H was 6.1. As a result, the submicron-order particles existing in the aqueous polyurethane dispersion grew into coalesced particles, with an average particle size of 7.5 μm1o and an occupancy (weight) of particles with a particle size in the range of 5D to 2D of 92. %, and the occupancy rate (number) of particles with a sphericity of 0.7 or more was 95%.

[Example 9] 834 parts by weight of the copolymerized polyester aqueous dispersion obtained in Example 3 and 35 parts by weight of deionized water were placed in a four-necked 5-liter separable flask equipped with a thermometer, condenser, and stirring blade. , and 1.6 parts by weight of dimethylamine were added. The pH of the bath was 12.2. Next, increase the bath temperature to 7
The temperature was raised to 0° C., and 100 parts by weight of an aqueous solution containing 0.5 parts by weight of ammonium belloxonisulfate was added dropwise over 40 minutes. The pH of the bath was 6.2. As a result, the copolymer with a particle size on the submicron order that existed in the copolymerized polyester aqueous dispersion grew into particles, and the average particle size was 4.8 μm.
Polyester particles were obtained in which 92% by weight of particles had a particle diameter in the range of 0°5D to 2D, where D was the m1 diameter.

(Effects of the Invention) As shown above, the present invention provides beads with a sharp particle size distribution whose main component is an ionic group-containing resin, which could not be obtained by conventional methods, and which can be used as a mass product. This is an excellent manufacturing method that enables production.

Claims (2)

[Claims] (1) Resin particles containing an ionic group-containing resin as a main component, and having an average particle diameter D of 1.0 to 100 μm,
At least 70% by weight of the particles fall within the range of 0.5D to 2.0D, and at least 70% of the particles have a sphericity (ratio of short axis to long axis) of 0.7 or higher on the number average. Resin particles characterized by: (2) A resin containing an ionic group is microdispersed in an aqueous medium to an average particle size of 0.1 μm or less, and the microdispersed particles are made into a plasticized state, so that the amount of ions in the dispersion is uniform and controlled. By changing the number, the micro-dispersed particles are combined, and the number average of particles with a sphericity of 0.7 or more is 70.
% or more of resin particles.