JP6341682B2 - Toner production method - Google Patents

Description

  The present invention relates to a toner for developing a latent electrostatic image to form a toner image in an image forming method such as an electrophotographic method or an electrostatic printing method, and a method for manufacturing the same.

  Conventionally, in order to improve image quality and high transferability, the toner has been spheroidized (the spheroidized toner is also referred to as “spherical toner” hereinafter).

  On the other hand, it is difficult to improve the cleaning property of the spherical toner.

  As a cause of the deterioration in cleaning performance, an electrostatic latent image carrier such as an electrophotographic photosensitive member (hereinafter also simply referred to as “photosensitive member”) and a cleaning blade (hereinafter also simply referred to as “blade”) as it is repeatedly used. The external additive that forms the blocking layer between the blade and the electrostatic latent image carrier is reduced, and the friction between the blade and the electrostatic latent image carrier is increased. Further, since the external additive is embedded on the surface of the toner particles, the friction between the electrostatic latent image carrier and the toner increases, and the toner slips between the blade and the electrostatic latent image carrier, The chatter of the blade may occur.

  Patent Document 1 discloses a technique for reducing the friction of a surface layer of an electrostatic latent image carrier in order to improve cleaning properties. With this technique, it is possible to increase the pressure for pressing the blade against the electrostatic latent image carrier as compared with the conventional technique. For this reason, even when a spherical toner for which it is difficult to improve the cleaning property is used, it is possible to suppress the deterioration of the cleaning property.

JP 2010-54772 A

  However, the technique disclosed in Patent Document 1 has a problem in that the surface of the electrostatic latent image carrier having reduced friction is scraped by repeated use, and the effect is difficult to sustain.

  An object of the present invention is to provide a toner that can maintain a high cleaning property even after repeated use, and a method for producing the same.

The present invention relates to a toner production method for producing a toner having toner particles and an external additive ,
As a step for producing the toner particles, it viewed including the following steps 1,
Step 1: Form polymerizable monomer composition particles containing a polymerizable monomer, a colorant, a release agent, an organic solvent and an organosilicon monomer in an aqueous medium, and the polymerizable monomer And the step of polymerizing each of the organosilicon monomers and removing the organic solvent :
The polymerizable monomer composition contains the organic solvent in an amount of 60 parts by mass to 100 parts by mass with respect to 100 parts by mass of the organosilicon monomer.
The toner particles have a shape factor SF1 of a cross section formed by a cross section polisher cross section method (CP cross section method) of 100 or more and 250 or less, and a value of the shape factor SF2 of the cross section is 350 or more. And a toner production method .

  According to the present invention, it is possible to provide a toner that can maintain a high cleaning property even after repeated use, and a method for producing the toner.

1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having an electrophotographic photosensitive member.

  The present inventors have a toner in which the shape factor SF1 of a cross section formed by a cross section polisher cross section method (hereinafter also referred to as “CP cross section method”) is 100 or more and 250 or less, and the shape factor SF2 of the cross section is 350 or more. It has been found that a toner having particles can maintain a high cleaning property even if it is repeatedly used, and the present invention has been achieved.

  About the effect of this invention, the present inventors consider as follows.

  The toner particles contained in the toner of the present invention have a different shape from the conventional toner particles. The shape of the toner particles contained in the toner of the present invention is close to the value of the toner particles contained in the spherical toner when the shape is quantified by a general projection method, for example, the average circularity.

  However, when the shape factor of the cross section of the toner particles contained in the toner of the present invention is measured by the CP cross section method, the value is the same as that of the conventional spherical toner or the toner particles contained in the irregular toner such as the pulverized toner. The value is different.

  The shape factor SF1 represents the “degree of roundness” of the toner particles. When the value is 100, the shape factor is a perfect circle. As the value increases, the shape factor SF1 becomes less round and becomes indefinite.

  The shape factor SF2 represents the “frequency of unevenness” of the toner. When the value is 100, the shape factor SF2 is a perfect circle. As the value increases, the frequency of unevenness increases.

  The toner particles contained in the toner of the present invention have higher values of the shape factors SF1 and SF2 than the conventional toner particles. That is, the shape of the toner particles contained in the toner of the present invention is a shape in which a plurality of large valleys exist on the surface and many fine irregularities exist on the surface.

  It is considered that the toner particles having the shape as described above can hold the external additive in a space (external additive holding space) existing between a large valley on the surface of the toner particle and fine irregularities. The external additive held in this space can reduce the friction between the electrostatic latent image carrier and the blade and the friction between the electrostatic latent image carrier and the toner even when used repeatedly. . Moreover, the blocking layer by the external additive can be maintained. As a result, it is possible to maintain high cleaning properties even after repeated use. More specifically, since the external additive adhering to the surface of the toner particles outside the space decreases with repeated use, the friction between the blade and the electrostatic latent image carrier increases, The friction between the electrostatic latent image carrier and the toner may increase. Then, the external additive held in the space comes out on the surface of the toner particles outside the section due to the impact caused by the increased friction. In other words, by repeated use, even if the external additive on the surface of the toner particles decreases, the external additive is appropriately replenished from the space. Therefore, since the degree of friction in the system is maintained in a moderate state for a long time compared to the conventional case, even if the surface of the electrostatic latent image carrier having reduced friction is scraped by repeated use, High cleaning performance is maintained.

  The toner of the present invention can be obtained, for example, by a specific method using a polymerizable organosilicon monomer and an organic solvent. For example, it is as follows.

  When toner particles are produced by a chemical production method, an organic solvent is added to the system, and after forming the particles, a step of removing the organic solvent is added to obtain deformed toner particles. This phenomenon is that when the organic solvent present in the particles is removed, the volume of the organic solvent shrinks, and the shape of the toner particles obtained with respect to the particles before the organic solvent removal is deformed. It is a phenomenon. This change in shape particularly affects the value of the shape factor SF1. By utilizing this phenomenon and controlling the type and amount of the organic solvent, the value of the shape factor SF1 of the toner particles can be controlled within the above range.

  By controlling the type and amount of the organosilicon monomer, fine irregularities can be formed on the surface of the toner particles, and the value of the shape factor SF2 of the toner particles can be controlled within the above range.

  In addition, when an alkoxysilane compound (a compound in which at least one of hydrogen of silane is substituted with an alkoxy group) is used as the organosilicon monomer, the organosilicon monomer generates alcohol as a by-product during the polymerization reaction. To do. For example, when the alkoxy group of the alkoxysilane compound has 1 or 2 carbon atoms, methanol or ethanol that is easily removed together with the organic solvent is generated as the alcohol. In such a case, in addition to the removal of the organic solvent, the shape of the removal of the alcohol as a by-product can be changed, and the shape factor SF1 can be changed more greatly. Moreover, the distillation temperature can be lowered by selecting a solvent having an azeotropic point in the alcohol as the organic solvent. Accordingly, since the organic solvent can be removed while the particles are relatively hard, a valley having a larger depression can be formed in the toner particles.

  The toner particles of the present invention can be produced, for example, through the following step 1 or the following step 2.

(Process 1)
Particles of a polymerizable monomer composition containing a polymerizable monomer, a colorant, a release agent, an organic solvent and an organosilicon monomer are formed in an aqueous medium, and the polymerizable monomer and the organic Each of the silicon monomers is polymerized to remove the organic solvent.

(Process 2)
Particles of an organic composition containing a binder resin, a colorant, a release agent, an organic solvent, and an organosilicon monomer are formed in an aqueous medium, the organosilicon monomer is polymerized, and the organic solvent is removed. To do.

(Polymerizable monomer)
Examples of the polymerizable monomer for producing toner particles include the following.

  Styrene monomers such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene; methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid Acrylic acid esters such as isobutyl and n-propyl acrylate; methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate and isobutyl methacrylate; acrylamide and the like.

  Among these polymerizable monomers, styrenic monomers are preferable from the viewpoint of development characteristics and durability of the toner, and it is more preferable to use a styrene monomer and another polymerizable monomer in combination. . The glass transition temperature (hereinafter also simply referred to as “Tg”) of the toner particles can be controlled by the mixing ratio of the polymerizable monomer. These polymerizable monomers can become a binder resin for toner particles by polymerization.

(Binder resin)
Examples of the binder resin for producing toner particles include vinyl resins such as styrene-acrylic resins, polyester resins, and hybrid resins in which vinyl resins and polyester resins are bonded. Specific examples include the following.

  Styrene resin, (meth) acrylic resin, styrene- (meth) acrylic resin, polyethylene resin, polyethylene-vinyl acetate resin, vinyl acetate resin, polybutadiene resin, phenol resin, polyurethane resin, polybutyral resin, polyester resin, and those Hybrid resin combined with resin.

  Among these resins, from the viewpoint of toner characteristics, styrene resin, (meth) acrylic resin, styrene- (meth) acrylic resin, polyester resin, hybrid resin in which styrene- (meth) acrylic resin and polyester resin are combined. Is preferred.

  Examples of the polyester resin include a polyester resin produced using a polyhydric alcohol and a polyhydric carboxylic acid, carboxylic anhydride or carboxylic acid ester as raw material monomers.

  Among these, polyester resins obtained by polycondensation of the following diol components and acid components are preferable.

  As the diol component, bisphenol derivatives.

  The acid component is a divalent or higher carboxylic acid or its acid anhydride.

  Examples of the divalent or higher carboxylic acid or acid anhydride thereof include fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid.

  As a hybrid resin, for example, a polyester unit and a vinyl polymer unit obtained by polymerizing a monomer having a carboxylic acid ester group such as (meth) acrylic acid ester are combined by transesterification to form Resin to be used.

  As the hybrid resin, a graft copolymer or block copolymer in which a vinyl polymer unit is a trunk polymer and a polyester unit is a branch polymer is preferable.

  Examples of the vinyl monomer for producing the vinyl polymer and the vinyl polymer unit are the same as those exemplified as the above-mentioned vinyl monomer.

(Dispersant)
When producing toner particles in an aqueous medium, it is preferable to add a dispersion stabilizer to the aqueous medium. Examples of the dispersion stabilizer include a surfactant, an organic dispersant, and an inorganic dispersant. Among these, inorganic dispersants are unlikely to produce ultrafine particles, and even when the polymerization temperature is changed, the stability of toner particle production is not easily lowered, and can be easily removed by washing. The adverse effect of the agent remaining on the toner particles hardly occurs. Therefore, an inorganic dispersant is suitable among the dispersants.

As an inorganic dispersing agent, the following are mentioned, for example.
Polyvalent metal phosphates such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate;
Carbonates such as calcium carbonate and magnesium carbonate; inorganic salts such as calcium metasilicate, calcium sulfate and barium sulfate;
Inorganic hydroxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide;
Inorganic oxides such as silica (silicon oxide) and alumina (aluminum oxide);
Bentonite etc.

  When an inorganic dispersant is used as the dispersion stabilizer, it may be used as it is by adding it to an aqueous medium, or it may be prepared and used in an aqueous medium using a compound capable of forming inorganic dispersant particles. When prepared and used in an aqueous medium, finer particles of inorganic dispersant are easily obtained.

  As an inorganic dispersant, for example, when water-insoluble tricalcium phosphate is to be used, an aqueous medium is mixed with an aqueous sodium phosphate solution and an aqueous calcium chloride solution at high speed to produce tricalcium phosphate. Can be made. In this way, more uniform and fine particles of tricalcium phosphate can be obtained. An inorganic dispersant that is soluble in acid or alkali, such as tricalcium phosphate, can be removed by adding acid or alkali after the polymerization to dissolve the inorganic dispersant.

  The inorganic dispersant is preferably used in an amount of 0.2 to 20.0 parts by mass with respect to 100.0 parts by mass of the polymerizable monomer. In this case, the surfactant may not be used in combination, or 0.001 part by mass or more and 0.100 part by mass or less of the surfactant may be used in combination with 100.0 parts by mass of the polymerizable monomer. .

Examples of the surfactant include the following.
Sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

(Coloring agent)
As the colorant, various dyes and pigments can be used.
Examples of the magenta colorant include C.I. I. Pigment red 3, 5, 17, 22, 23, 38, 41, 112, 122, 123, 146, 149, 178, 179, 190, 202, C.I. I. Pigment violet 19, 23 and the like. These may be used alone or in combination of two or more (dyes and pigments).

  Examples of cyan colorants include C.I. I. Pigment Blue 15, 15: 1, 15: 3, and copper phthalocyanine pigments obtained by substituting 1 to 5 phthalimidomethyl groups on the phthalocyanine skeleton. These may be used alone or in combination of two or more (dyes and pigments).

  Examples of the colorant for yellow include C.I. I. Pigment yellow 1, 3, 12, 13, 14, 55, 73, 74, 83, 93, 94, 95, 97, 98, 109, 110, 154, 155, 166, 180, 185 and the like. These may be used alone or in combination of two or more (dyes and pigments).

  Examples of the black colorant include carbon black, aniline black, acetylene black, and titanium black. These may be used alone or in combination of two or more. In addition, the above-described magenta colorant, cyan colorant, and yellow color may be used and the color may be adjusted to black.

  The content of the colorant in the toner particles is preferably 0.10 parts by mass or more and 60.00 parts by mass or less, and 0.5 parts by mass or more and 50.0 parts by mass with respect to 100.0 parts by mass of the binder resin. It is more preferable that the amount is not more than parts.

(Release agent)
At the time of fixing the toner, in order to improve the offset property to the fixing device, a releasing agent such as oil can be applied to the fixing device, or a releasing agent such as wax can be contained in the toner particles.

Examples of the release agent contained in the toner include the following.
Petroleum waxes such as paraffin wax, microcrystalline wax, petrolatum and derivatives thereof;
Montan wax and its derivatives;
Hydrocarbon wax and its derivatives by Fischer-Tropsch process;
Polyolefin waxes such as polyethylene and derivatives thereof;
Natural waxes such as carnauba wax and candelilla wax and their derivatives.

  Examples of the derivatives include oxides, block copolymers with vinyl monomers, and graft modified products.

  In addition, as a release agent to be contained in the toner, higher aliphatic alcohols, fatty acids such as stearic acid and palmitic acid, compounds thereof, acid amide waxes, ester waxes, ketones, plant waxes, animal waxes, and the like are also included. Can be used.

  Among these release agents, paraffin wax is preferable when toner particles are produced by a suspension polymerization method from the viewpoint of easy inclusion in toner particles.

  The content of the release agent in the toner particles is preferably 2.5 parts by mass or more and 15.0 parts by mass or less, and 3.0 parts by mass or more and 10.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin. It is more preferable that the amount is not more than part by mass. The higher the content of the release agent, the easier oilless fixing (fixing in a system in which no oil is applied to the fixing device). Further, as the content of the release agent is smaller, the excess release agent is less likely to be present on the surface of the toner particles, and the charging characteristics are less likely to be hindered.

(Crosslinking agent)
Further, when producing toner particles using a polymerizable monomer, it is preferable to use a small amount of a polyfunctional polymerizable monomer in combination from the viewpoint of high temperature offset resistance. The high temperature offset is a phenomenon in which part of the toner particles melted at the time of fixing adheres to the surface of a fixing device (such as a heat roller or a fixing film) and this contaminates a subsequent transfer material (such as paper). As the polyfunctional polymerizable monomer, a compound having two or more polymerizable double bonds is preferably used, and examples thereof include the following.
Aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene;
Carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate;
Divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone;
Compounds having 3 or more vinyl groups.

  When a polyfunctional polymerizable monomer is used, the amount used is 0.01 parts by mass or more with respect to 100.00 parts by mass of a non-polyfunctional polymerizable monomer (monofunctional polymerizable monomer). It is preferable that it is 1.00 mass part or less.

(Initiator)
In the production of toner particles, a polymerization initiator can be used.

  Examples of the polymerization initiator include a peroxide polymerization initiator and an azo polymerization initiator.

Examples of organic peroxide polymerization initiators include the following.
Peroxyester, peroxydicarbonate, dialkyl peroxide, peroxyketal, ketone peroxide, hydroperoxide, diacyl peroxide and the like.

Examples of inorganic peroxide polymerization initiators include persulfates and hydrogen peroxide. Specific examples include the following.
t-butyl peroxyacetate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-hexyl peroxyacetate, t-hexyl peroxypivalate, t-hexyl peroxyisobutyrate, t- Peroxyesters such as butyl peroxyisopropyl monocarbonate, t-butylperoxy 2-ethylhexyl monocarbonate;
Diacyl peroxides such as benzoyl peroxide;
Peroxydicarbonates such as diisopropylperoxydicarbonate;
Peroxyketals such as 1,1-di-t-hexylperoxycyclohexane;
Dialkyl peroxides such as di-t-butyl peroxide;
t-butyl peroxyallyl monocarbonate and the like.

Examples of the azo polymerization initiator include the following.
2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis -4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile, dimethyl-2,2'-azobis (2-methylpropionate) and the like.

(Organic solvent)
The organic solvent used for producing the toner particles is preferably an organic solvent having an octanol / water partition coefficient logPow of less than 4.0 from the viewpoint of easy removal from the aqueous medium later.

As such an organic solvent, the following are mentioned, for example.
Toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methyl cyclohexane and the like.

  During particle formation (granulation), it is preferable that the organic solvent stays to some extent in the particle, and therefore a slightly hydrophobic organic solvent that satisfies 2.5 <logPow <4.0 is more preferable.

  Examples of such an organic solvent include toluene and methylcyclohexane.

  When the toner particles of the present invention are produced through the step 1 or the step 2, the value of the shape factor SF1 of the toner particles can be changed by changing the amount of the organic solvent. As the amount of the organic solvent increases, the value of the shape factor SF1 of the toner particles tends to increase.

  When the toner particles of the present invention are produced through the above step 1 or the above step 2, the polymerizable monomer composition / organic composition contains 60 parts by mass of an organic solvent with respect to 100 parts by mass of the organosilicon monomer. The content is preferably 100 parts by mass or less.

(Organosilicon monomer)
When the toner particles of the present invention are produced through the step 1 or the step 2, an organosilicon monomer is polymerized to produce an organosilicon polymer. As a method for producing the organosilicon polymer, for example, a sol-gel method can be used.

The sol-gel method uses a metal alkoxide: M (OR) _n (M represents a metal atom, O represents an oxygen atom, R represents a hydrocarbon group, and n represents an oxidation number of the metal atom). In this method, hydrolysis and condensation polymerization are performed in a solvent, and after gelation through a sol state, an organic-inorganic hybrid or the like is synthesized. In addition to organic-inorganic hybrids, glass, ceramics, nanocomposites, etc. can also be synthesized.

  According to the sol-gel method, functional materials of various shapes such as coating layers, fibers, bulk bodies, and fine particles can be produced from a liquid phase at a low temperature.

  Furthermore, since the sol-gel method is a method for starting a functional material by starting from a solution and gelling the functional material, it is possible to manufacture functional materials having various microstructures and shapes.

  When the toner particles are produced in an aqueous medium, the organosilicon monomer is likely to be deposited on the surface of the particles due to the hydrophilicity due to a hydrophilic group such as a silanol group.

  However, when the hydrophobicity is large, for example, the larger the total number of carbon atoms of the hydrocarbon group such as an alkyl group of the organosilicon monomer, the stronger the hydrophobicity of the organosilicon monomer. When the hydrophobicity of the organosilicon monomer is increased, an aggregate of organosilicon polymer particles tends to be formed on the surface of the toner particles. The microstructure and shape of the aggregate of the organosilicon polymer particles can be adjusted by the reaction temperature, reaction time, reaction solvent, pH, type and amount of the organometallic compound, and the like.

  In order to obtain the organosilicon polymer as described above, it is preferable to use one or more kinds of organosilicon monomers represented by the following formula (1).

In the formula (1), R ¹ represents an alkyl group, a hydrocarbon group selected from the group consisting of vinyl and allyl groups. R ^{2 to} R ⁴ each independently represent a reactive group selected from the group consisting of a hydroxy group, an alkoxy group, an acetoxy group, and a halogen atom.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the alkoxy group include a methoxy group and an ethoxy group.
As a halogen atom, a chlorine atom etc. are mentioned, for example.

Examples of the organosilicon monomer represented by the above formula (1) include the following.
Methyltrimethoxysilane, methyltriethoxysilane, methyldiethoxymethoxysilane, methylethoxydimethoxysilane, methyltrichlorosilane, methylmethoxydichlorosilane, methylethoxydichlorosilane, methyldimethoxychlorosilane, methylmethoxyethoxychlorosilane, methyldiethoxychlorosilane, methyl Triacetoxysilane, methyldiacetoxymethoxysilane, methyldiacetoxyethoxysilane, methylacetoxydimethoxysilane, methylacetoxymethoxysilane, methylacetoxydiethoxysilane, methyltrihydroxysilane, methylmethoxydihydroxysilane, methylethoxydihydroxysilane, methyldimethoxyhydroxy Silane, methylethoxymethoxyhydroxysilane, methyl Diethoxyhydroxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltrichlorosilane, ethyltriacetoxysilane, ethyltrihydroxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltrichlorosilane, propyltriacetoxysilane, propyltri Hydroxysilane, butyltrimethoxysilane, butyltriethoxysilane, butyltrichlorosilane, butyltriacetoxysilane, butyltrihydroxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyldiethoxymethoxysilane, vinylethoxydimethoxysilane, vinyltri Chlorosilane, vinylmethoxydichlorosilane, vinylethoxydichlorosilane, vinyldimethoxychlorosilane, Nylmethoxyethoxychlorosilane, vinyldiethoxychlorosilane, vinyltriacetoxysilane, vinyldiacetoxymethoxysilane, vinyldiacetoxyethoxysilane, vinylacetoxydimethoxysilane, vinylacetoxymethoxysilane, vinylacetoxydiethoxysilane, vinyltrihydroxysilane, vinylmethoxy Dihydroxysilane, vinylethoxydihydroxysilane, vinyldimethoxyhydroxysilane, vinylethoxymethoxyhydroxysilane, vinyldiethoxyhydroxysilane, allyltrimethoxysilane, allyltriethoxysilane, allyltrichlorosilane, allyltriacetoxysilane, allyltrihydroxysilane and the like.

  The organosilicon monomer is preferably used in an amount of 5.0 parts by mass or more, more preferably 10.0 parts by mass or more, based on 100.0 parts by mass of the polymerizable monomer / binder resin. .

  By increasing or decreasing the amount of the organosilicon monomer used, the degree of unevenness on the surface of the toner particles changes, and as the amount used increases, a clear granular material tends to be observed.

  The toner particles of the present invention are preferably produced in an aqueous medium, for example, as in Step 1 and Step 2 above, from the viewpoint of uniformly forming an organosilicon polymer on the surface of the toner particles. Therefore, the hydrocarbon group contained in the organosilicon monomer is preferably a group having a small number of carbon atoms and high hydrophilicity.

Further, when toner particles are produced through the above step 1 and the organosilicon monomer represented by the above formula (1) is used as the organosilicon monomer, R ¹ in the above formula (1) is used in combination. A functional group that is difficult to react with the polymerizable monomer is preferable, and an alkyl group is preferable. When R ¹ in the above formula (1) is a functional group that does not easily react with the polymerizable monomer, the organic silicon monomer represented by the above formula (1) is likely to be deposited on the toner surface.

When the organosilicon monomer represented by the above formula (1) is used as the organosilicon monomer, a by-product during condensation polymerization depends on the number of carbons in the reactive groups R ^{2 to} R ^{4 in} the above formula (1). The kind of alcohol that is a thing is decided. Thus, by controlling the number of carbon atoms of the reactive group R ² to R ^4, it is possible to control the azeotropic effect with the organic solvent. As described above, the azeotropic effect with the organic solvent makes it possible to lower the solvent removal temperature (distillation temperature), and the organic solvent can be removed while the particles are relatively hard. Due to this effect, it is possible to form a valley with a larger depression in the toner particles, the shape change due to the solvent removal of the toner particles is further increased, and it is possible to further increase the value of the shape factor SF1 of the toner particles. Become.

(External additive)
By mixing toner particles and an external additive (fluidity improver) with a mixer such as a Henschel mixer, a toner with improved fluidity can be obtained.

  Examples of the fluidity improver include the following.

  Fluorine-based resin particles such as vinylidene fluoride fine particles and polytetrafluoroethylene fine particles; silica fine particles produced by a wet production method, silica fine particles such as silica fine particles produced by a dry production method; silane coupling agent, titanium for silica fine particles Treated silica fine particles surface-treated with a treatment agent such as a coupling agent or silicone oil; titania (titanium oxide) fine particles; surface treated with a treatment agent such as a silane coupling agent, a titanium coupling agent, or silicone oil Treated titania fine particles subjected to treatment; alumina fine particles; treated alumina fine particles obtained by subjecting the alumina fine particles to surface treatment with a treatment agent such as a silane coupling agent, a titanium coupling agent, or silicone oil.

The fluidity improver preferably has a specific surface area (BET specific surface area) of 30 m ² / g or more, more preferably 50 m ² / g or more by nitrogen adsorption measured by the BET method.

  The content of the external additive (fluidity improver) in the toner is preferably 0.01 parts by mass or more and 8.0 parts by mass or less, and 0.1 parts by mass with respect to 100.0 parts by mass of the toner particles. More preferably, it is 4.0 parts by mass or less.

  Next, step 1 and step 2 that can be employed in the production of the toner particles of the present invention will be described in detail.

(Process 1)
Suspension polymerization method The suspension polymerization method is a method in which particles of a polymerizable monomer composition containing a polymerizable monomer, a colorant, and a release agent are formed in an aqueous medium, and the polymerizable monomer is formed. In this method, toner particles are obtained by polymerization. In step 1 above, an organic solvent and an organosilicon monomer are added to the polymerizable monomer composition.

  Specifically, first, a colorant, a release agent, an organosilicon monomer, and an organic solvent are added to a polymerizable monomer that is a raw material of a binder resin that is a main component of toner particles, and a disperser is used. These are uniformly dissolved and / or dispersed to prepare a polymerizable monomer composition. Examples of the disperser include a homogenizer, a ball mill, a colloid mill, and an ultrasonic disperser.

  A polymerization initiator, a polyfunctional polymerizable monomer, a chain transfer agent, a charge control agent, a plasticizer, and the like may be added to the polymerizable monomer composition as necessary. Moreover, you may add another additive (For example, a pigment dispersant, a mold release agent dispersing agent, etc.) to the said polymeric monomer composition as needed.

  Next, the polymerizable monomer composition is added to an aqueous medium and suspended using a disperser to form (granulate) particles of the polymerizable monomer composition. Examples of the disperser include a high-speed stirrer and an ultrasonic disperser. If necessary, the aqueous medium may contain a dispersion stabilizer in advance.

  When a polymerization initiator is used, the polymerization initiator may be mixed with other additives when preparing the polymerizable monomer composition, or immediately before adding the polymerizable monomer composition to the aqueous medium. May be mixed with the polymerizable monomer composition. Moreover, a polymerization initiator can also be added in the state melt | dissolved in the polymerizable monomer or another solvent during granulation or after granulation completion, ie, just before starting a polymerization reaction.

  In the polymerization reaction of the polymerizable monomer or the like contained in the particles of the polymerizable monomer composition, it is preferable to heat the suspension after granulation to 50 ° C. or higher and 90 ° C. or lower. Further, it is preferable to carry out the polymerization reaction while stirring so that the particles of the polymerizable monomer composition in the suspension maintain a particle state and the particles do not float or settle.

  The polymerization initiator is preferably one that is easily decomposed by heating to generate a free radical. When the polymerizable monomer has an unsaturated bond, the generated radical is added to the unsaturated bond to newly generate an adduct radical. The generated adduct radical is further added to an unsaturated bond of another polymerizable monomer. By repeating such an addition reaction in a chain manner, the polymerization reaction proceeds, and toner particles mainly composed of a binder resin derived from the polymerizable monomer are formed. Along with the polymerization reaction of the polymerizable monomer, hydrolysis and condensation polymerization of the organosilicon monomer cause gelation to progress through the sol state on the surface of the particles, and an organosilicon layer is formed.

・ Removal of organic solvent A distillation apparatus is attached to a container containing an aqueous medium containing particles.

  Subsequently, ion exchange water is added, and the temperature in the container is raised until a distillation fraction comes out. The amount of distillation fraction is preferably equal to or more than the amount of ion-exchanged water added previously. Although the volume of the toner particles is reduced by removing the organic solvent or the like, a hard organosilicon layer with little volume change is formed on the surface of the toner particles. Accordingly, the toner particles are dented by the volume reduction.

(Process 2)
Dissolution suspension method The dissolution suspension method is a method in which particles of an organic composition obtained by dissolving and / or dispersing a binder resin, a colorant and a release agent in an organic solvent are formed in an aqueous medium. In which toner particles are obtained. In step 2 above, an organosilicon monomer is added to the polymerizable monomer composition.

  Specifically, first, a binder resin that is a main component of toner particles, a colorant, a release agent, and an organosilicon monomer are added to an organic solvent, and these are dissolved and / or dispersed in an organic solvent to form an organic solvent. A composition is prepared.

  You may add a charge control agent, a plasticizer, etc. to the said organic composition as needed. Moreover, you may add another additive (For example, a pigment dispersant, a mold release agent dispersing agent, etc.) to the said organic composition as needed.

  Next, the organic composition is added to an aqueous medium to form (granulate) particles of the organic composition. If necessary, the aqueous medium may contain a dispersion stabilizer in advance.

  Next, the temperature in the system is gradually raised to 80 ° C. and maintained for 3 hours to 5 hours. Meanwhile, the organosilicon monomer undergoes hydrolysis and condensation polymerization to form a gel on the surface of the particle through a sol state to form an organosilicon layer.

-Removal of organic solvent Same as removal of organic solvent in step 1 above.

[Electrophotographic equipment]
FIG. 1 shows an example of a schematic configuration of an electrophotographic apparatus provided with a process cartridge having an electrophotographic photosensitive member.

  In FIG. 1, reference numeral 1 denotes a cylindrical electrophotographic photosensitive member, which is driven to rotate at a predetermined peripheral speed in the direction of an arrow about an axis 2. The surface of the electrophotographic photosensitive member 1 that is driven to rotate is uniformly charged to a predetermined negative potential by a charging unit (primary charging unit: charging roller or the like) 3 during the rotation process. Next, exposure light (image exposure light) 4 modulated in intensity corresponding to a time-series electric digital image signal of target image information output from exposure means (not shown) such as slit exposure or laser beam scanning exposure is received. . Thus, an electrostatic latent image corresponding to the target image is formed on the surface of the electrophotographic photosensitive member 1.

  The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is developed (reversal development or normal development) with toner stored in the developing means 5 to become a toner image.

  Next, the toner image formed on the surface of the electrophotographic photosensitive member 1 is transferred to a transfer material (paper or the like) P by a transfer bias from a transfer means (transfer roller or the like) 6. The transfer material P is taken out from the transfer material supply means (not shown) in synchronization with the rotation of the electrophotographic photosensitive member 1 and fed between the electrophotographic photosensitive member 1 and the transfer means 6 (contact portion). .

  The transfer material P that has received the transfer of the toner image is separated from the surface of the electrophotographic photosensitive member 1, transported to the fixing means 8, and subjected to a fixing process of the toner image. It is conveyed outside the photographic device.

  The surface of the electrophotographic photosensitive member 1 after the toner image is transferred is cleaned by receiving the transfer residual toner (transfer residual toner) by a cleaning means (cleaning blade or the like) 7. Next, after being subjected to charge removal processing by pre-exposure light (not shown) from pre-exposure means (not shown), it is repeatedly used for image formation. As shown in FIG. 1, when the charging unit 3 is a contact charging unit using a charging roller or the like, pre-exposure is not necessarily required.

  In the present invention, a plurality of components such as the electrophotographic photosensitive member 1, the charging unit 3, the developing unit 5, the transfer unit 6 and the cleaning unit 7 are selected and stored in a container. As a single unit. The process cartridge may be configured to be detachable from an electrophotographic apparatus main body such as a copying machine or a laser beam printer. In FIG. 1, an electrophotographic photosensitive member 1, a charging unit 3, a developing unit 5 and a cleaning unit 7 are integrally supported to form a cartridge, and an electrophotographic apparatus is provided using a guide unit 10 such as a rail of the electrophotographic apparatus main body. The process cartridge 9 is detachable from the main body.

  The toner of the present invention is a case where the electrophotographic photosensitive member has been subjected to friction reduction processing due to its characteristic shape, and even when the effect of the processing is reduced by repeating image formation, It becomes possible to keep the cleaning property high.

(Measurement method of toner particle shape factors SF1 and SF2 by CP cross-section method)
In the present invention, a cross section polisher (trade name: SM-09010) manufactured by JEOL Ltd. was used to measure the shape factor of the toner by the CP cross-section method. Then, a cross section of the toner particles was prepared as described later.

  A carbon double-sided PSA sheet piece is stuck on a silicon wafer, Mo mesh (diameter: 3 mm / thickness: 30 μm) is fixed, and about one layer of toner (thickness of about one toner particle) is adhered thereon. After depositing platinum on this, a cross section of a toner particle was formed using a cross section polisher under conditions of an acceleration voltage of 4 kV and a processing time of 3 hours.

  The cross section of the formed toner particles was observed using an FE-SEM (trade name: S-4700) manufactured by Hitachi, Ltd. and an observation magnification of 2000 times.

  The cross-sectional image of the toner particles was analyzed using image analysis software (trade name: analySIS Pro) manufactured by Olympus Corporation. An absolute maximum length R, a peripheral length L, and a cross-sectional area S of the cross section of the toner particles were obtained. From the circumference of the obtained toner particles, the equivalent circle diameter r is obtained from the equivalent circle diameter r = L / π, and the value is ± 10% of the weight average diameter D4 obtained by the method described later using a Coulter counter. The particles included in the width of the particle were regarded as corresponding particles.

Randomly selecting 100 of the above particles, and calculating the average of the absolute maximum lengths of their cross sections as Rav. And the average perimeter is Lav. And the average cross-sectional area is Sav. And the values of the shape factors SF1 and SF2 of the cross section of the toner particles were obtained from the following formula.
Shape factor SF1 = {(Rav. × 2) / (Sav. × 100π)} / 4
Shape factor SF2 = {(Lav. × 2) / (Sav. × 100)} / 4π

(Average circularity)
In the present invention, a flow type particle image analyzer (trade name: FPIA-3000 type) manufactured by Sysmex Corporation was used to measure the average circularity of the toner.

  As a specific measurement method, first, an appropriate amount of a surfactant (alkyl benzene sulfonate) as a dispersant was added to 20 mL of ion-exchanged water, and then 0.02 g of a measurement sample was added. Then, a dispersion process for measurement is performed by performing a dispersion process for 2 minutes using a tabletop ultrasonic cleaner disperser (trade name: VS-150, oscillation frequency: 50 kHz, electrical output: 150 W) manufactured by VervoCrea. A liquid was used. In that case, it adjusted so that the temperature of a dispersion liquid might be 10 degreeC or more and 40 degrees C or less.

  For the measurement, the above-mentioned flow type particle image measuring device equipped with a 10 × standard objective lens was used, and a particle sheath (trade name: PSE-900A) manufactured by Sysmex Corporation was used as the sheath liquid.

  The dispersion prepared according to the above procedure is introduced into the flow type particle image measuring apparatus, 3000 toner particles are measured in the total count mode, and the analysis particle diameter is limited to the equivalent circle diameter of 3.00 μm or more and 200.00 μm or less. Then, the average circularity of the toner particles was determined.

  In measurement, automatic focus adjustment was performed using standard latex particles (specifically, standard latex particles manufactured by Duke Scientific (trade name: 5200A) diluted with ion-exchanged water) before the measurement was started. . Thereafter, focus adjustment was performed every 2 hours from the start of measurement.

  In addition, as the flow type particle image measuring device, a flow type particle image measuring device which has been calibrated by Sysmex Corporation and has received a calibration certificate issued by Sysmex Corporation was used. Measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle diameter was limited to a circle equivalent diameter of 3.00 μm or more and 200.00 μm or less.

  The average circularity of the toner is preferably 0.970 or more. The average circularity of the toner is an index representing the complexity of the surface shape of the toner particles. When the toner particles are perfectly spherical, the circularity is 1.000, and becomes smaller as the shape becomes more complicated. That is, that the average circularity is 0.970 or more means that the shape of the toner particles contained in the toner is substantially spherical. The toner having toner particles having such a shape tends to have uniform frictional charging and is effective in suppressing fogging and sleeve ghosting. In addition, when adopting a method in which toner is carried on a toner carrier, and development is performed by forming toner spikes, the toner spikes are likely to be uniform. In addition, if the toner particles are spherical, the toner has good fluidity, and the toner is less susceptible to stress in the developing means (developer), so that the toner can be charged even in long-term use under high humidity. Is difficult to decrease. Also, during fixing, heat and pressure are easily applied uniformly to the entire toner, so that fixing properties are easily improved.

(Weight average particle diameter (D4))
In the present invention, the weight average particle diameter (D4) of the toner is calculated as follows.

  As a measuring device, a precision particle size distribution measuring device Coulter counter (trade name: Multisizer 3) manufactured by Beckman Coulter was used. This is a precision particle size distribution measuring apparatus by a pore electrical resistance method equipped with a 100 μm aperture tube. For setting the measurement conditions and analyzing the measurement data, dedicated software (trade name: Beckman Coulter Multisizer 3 Version 3.51) attached to the same device of the same company was used. The measurement was performed with 25,000 effective measurement channels.

  As the electrolytic aqueous solution used for the measurement, a special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of 1% by mass, specifically, an electrolytic aqueous solution manufactured by Beckman Coulter (trade name: ISOTON II). )It was used.

  Prior to measurement and analysis, the dedicated software was set as follows.

  On the “Change Standard Measurement Method (SOM)” screen of the dedicated software, the total count in the control mode was set to 50000 particles. The measurement was performed once, and the Kd value was set to a value obtained using “standard particles 10.0 μm” (manufactured by Beckman Coulter). The threshold value and the noise level were automatically set by pressing the “threshold / noise level measurement button”. The current was set to 1600 μA, the gain was set to 2, the electrolyte was set to ISOTON II, and the “aperture tube flush after measurement” was checked.

  In the “Pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set from 2 μm to 60 μm. .

  A more specific measuring method is as follows.

  (1) The electrolytic aqueous solution 200 mL was placed in a glass 250 ml round bottom beaker exclusively for the Multisizer 3 and set on a sample stand, and the stirrer rod was stirred counterclockwise at 24 rpm. And the dirt and bubbles in the aperture tube were removed by the “aperture flush” function of the dedicated software.

  (2) 30 mL of the electrolytic solution was placed in a glass 100 mL flat bottom beaker. Into this, 0.3 mL of a diluent prepared by diluting the dispersant with ion exchange water 3 times by mass was added. As this dispersant, Wako Pure Chemical Industries, Ltd. Contaminone N (trade name) (Neutral detergent 10 for washing precision measuring instruments having a pH of 7 comprising a nonionic surfactant, an anionic surfactant and an organic builder) Mass% aqueous solution) was used.

  (3) An ultrasonic disperser (trade name: Ultrasonic Disposition System Tetora 150) manufactured by Nikka Ki Bios Co., Ltd. was prepared. This ultrasonic disperser incorporates two oscillators with an oscillation frequency of 50 kHz with the phases shifted by 180 degrees, and the electrical output is 120 W. 3.3 L of ion-exchanged water was placed in the water tank of the ultrasonic disperser, and 2 mL of Contaminone N was added to the water tank.

  (4) The beaker of (2) was set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser was operated. Then, the height position of the beaker was adjusted so that the resonance state of the liquid surface of the electrolytic aqueous solution in the beaker was maximized.

  (5) In a state where the electrolytic aqueous solution in the beaker of (4) was irradiated with ultrasonic waves, 10 mg of toner was added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion treatment was further continued for 60 seconds. In ultrasonic dispersion, the water temperature in the water tank was adjusted to be 10 ° C. or higher and 40 ° C. or lower.

  (6) The electrolyte aqueous solution of (5) in which the toner was dispersed was dropped using a pipette into the round bottom beaker of (1) installed in a sample stand, and the measurement concentration was adjusted to 5%. The measurement was performed until the number of measured particles reached 50,000.

  (7) The obtained measurement data was analyzed with the dedicated software, and the weight average particle diameter (D4) was calculated. The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when “graph / volume%” is set in the dedicated software is the weight average particle diameter (D4).

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. “Parts” in the examples represents “parts by mass”.

[Production Example of Toner 1]
-Preparation of pigment dispersion paste Styrene monomer 39.0 parts Copper phthalocyanine (CI Pigment Blue 15: 3 (manufactured by Dainichi Seika Kogyo Co., Ltd.)) 6.5 parts After pre-mixing the above materials in a container, While maintaining it at 20 ° C. or lower, it was dispersed in a bead mill for 4 hours to produce a pigment dispersion paste.

Preparation of toner particles In a four-necked vessel equipped with a reflux tube, a stirrer, a thermometer, and a nitrogen introduction tube, 700.0 parts of ion-exchanged water, 1000.0 parts of a 0.1 mol / L Na ₃ PO ₄ aqueous solution, and 24.0 parts of 1.0 mol / L HCl aqueous solution was added, heated to 60 ° C., and then rotated at 13000 rpm using a precision dispersion / emulsifier (trade name: Creamix) manufactured by M Technique Co., Ltd. Stirring under conditions. To this, 85 parts of a 1.0 mol / L CaCl ₂ aqueous solution was added to prepare a dispersion medium (aqueous medium) containing Ca ₃ (PO ₄ ) ₂ as an inorganic dispersant.

next,
Pigment dispersion paste 39.0 parts Styrene monomer 31.0 parts n-Butyl acrylate 30.0 parts Saturated polyester resin (copolymer of terephthalic acid and propylene oxide-modified bisphenol A, acid value: 13 mg KOH / g, weight average molecular weight (Hereinafter also simply referred to as “Mw”): 14500) 5.0 parts Ester wax 9.0 parts Organosilicon monomer (methyltriethoxysilane) 30.0 parts Toluene 20.0 parts Warm, dissolve and disperse to obtain a mixture. Further, while maintaining at 60 ° C., 3.0 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) was added as a polymerization initiator and dissolved to prepare a polymerizable monomer composition.

  The polymerizable monomer composition was charged into the dispersion medium. Then, it was made into nitrogen atmosphere at 60 degreeC, and it stirred for 10 minutes on the conditions of rotation speed 12000rpm using the said precision dispersion and emulsifier, and formed the particle | grains of the polymerizable monomer composition. Thereafter, the mixture was reacted at 70 ° C. for 5 hours while stirring with a paddle stirring blade, and then stirred at 85 ° C. for 5 hours to complete the polymerization. In the meantime, the organosilicon monomer gelled through the sol state on the surface of the particles by hydrolysis and condensation polymerization to form an organosilicon layer.

Subsequently, the reflux tube was removed and a distillation apparatus was attached. Thereafter, 300 parts of ion-exchanged water was added and distillation was started. Then, a distillation fraction started to appear at around 77 ° C., which is the azeotropic point of ethanol and toluene. The temperature was maintained until the distillation fraction reached 310.0 parts to obtain a polymer slurry. Then, it cooled to 30 degreeC. Thereafter, hydrochloric acid was added to the container containing the polymer slurry to dissolve and remove Ca ₃ (PO ₄ ) ₂ . Further, the toner particles were obtained by filtration, washing and drying.

  The obtained toner particles were classified, and hydrophobic silica fine particles were externally added by the following operation to obtain a toner.

That is, the surface of the silica fine particles was treated with hexamethyldisilazane and then treated with silicone oil to obtain hydrophobic silica fine particles having a number average primary particle size of 9 nm and a BET specific surface area of 180 m ² / g. 1.0 part of the hydrophobic silica fine particles and 100 parts of the classified toner particles were mixed with a Henschel mixer manufactured by Mitsui Miike Chemical Co., Ltd., and the hydrophobic silica fine particles were externally added to the toner particles to obtain toner 1. .

  The obtained toner 1 had a weight average particle diameter (D4) of 6.5 μm and an average circularity of 0.974. The shape factor SF1 was 216, and the shape factor SF2 was 1272.

  The shape of the obtained toner is shown in Table 1.

[Production Example of Toner 2]
Production of toner 1 except that 30.0 parts of methyltriethoxysilane used in the production example of toner 1 are changed to 40.0 parts of methyltriethoxysilane and 20.0 parts of toluene are changed to 10.0 parts of toluene. A toner was produced in the same manner as in Example, and Toner 2 was obtained.

[Production Example of Toner 3]
Toner 3 was obtained in the same manner as in Toner 1 except that 30.0 parts of methyltriethoxysilane used in Toner 1 were changed to 10.0 parts of methyltriethoxysilane. .

[Production Example of Toner 4]
Toner 4 was obtained in the same manner as in Toner 1 except that 20.0 parts of toluene used in Toner 1 were changed to 40.0 parts of toluene.

[Production Example of Toner 5]
Toner particles 5 were obtained in the same manner as in Toner 1 except that 20.0 parts of toluene used in Toner 1 were changed to 20.0 parts of methylcyclohexane.

[Production Example of Toner 6]
-Preparation of organic composition mixed liquid Styrene-n-butyl acrylate copolymer (Tg: 58 ° C, Mw: 22000) 100.0 parts Copper phthalocyanine (CI Pigment Blue 15: 3 (Daiichi Seikagaku Corporation) ))) 5.0 parts Paraffin wax (trade name: HNP-7, manufactured by Nippon Seiki Co., Ltd.) 8.0 parts Organosilicon monomer (methyltriethoxysilane) 30.0 parts Toluene 50.0 parts After premixing the above materials in a container, the mixture was dispersed in a bead mill for 4 hours while keeping it at 20 ° C. or lower to prepare an organic composition mixed solution.

Preparation of toner particles 78 parts of 0.1 mol / L Na ₃ PO ₄ aqueous solution is added to 240 parts of ion-exchanged water, heated to 60 ° C., and precision disperser / emulsifier manufactured by M Technique Co., Ltd. (trade name) : CLEARMIX) and stirred at a rotational speed of 14,000 rpm. To this, 12 parts of a 1.0 mol / L CaCl ₂ aqueous solution was added to obtain a dispersion medium (aqueous medium) containing Ca ₃ (PO ₄ ) ₂ . Furthermore, 1.0 part of carboxymethylcellulose (trade name: Serogen BS-H, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added and stirred for 10 minutes.

  While the temperature of the dispersion medium prepared in the container of the precision dispersion / emulsifying machine is adjusted to 30 ° C. and stirring, 180 parts of the organic composition mixed solution adjusted to a temperature of 30 ° C. is added. After stirring for a minute, the operation was stopped to obtain a toner composition dispersion suspension. While stirring the obtained toner composition dispersion suspension, the temperature in the system was gradually raised to 80 ° C. and maintained for about 3 to 5 hours. Meanwhile, the organosilicon monomer gelled through the sol state on the surface of the particles by hydrolysis and condensation polymerization to form an organosilicon layer.

Next, a distillation apparatus was attached. Thereafter, 300 parts of ion-exchanged water was added and distillation was started. Then, a distillation fraction started to appear at around 77 ° C., which is the azeotropic point of ethanol and toluene. The temperature was maintained until the distillation fraction reached 310.0 parts. After cooling to room temperature, hydrochloric acid was added to dissolve and remove Ca ₃ (PO ₄ ) ₂ . Further, the toner particles were obtained by filtration, washing with water and drying.

  The obtained toner particles were classified, and hydrophobic silica fine particles were externally added to the toner particles in the same manner as in the toner 1 production example, whereby toner 6 was obtained.

[Production Example of Toner 7]
Toner 7 was obtained in the same manner as in Toner 6 except that 50.0 parts of toluene used in Toner 6 were changed to 50.0 parts of methylcyclohexane.

[Production Example of Toner 8]
Toner 8 was obtained in the same manner as in Toner 1 except that 30.0 parts of methyltriethoxysilane used in Toner 1 were changed to 30.0 parts of ethyltriethoxysilane. .

[Production Example of Toner 9]
Production of toner 1 except that 30.0 parts of methyltriethoxysilane used in the production example of toner 1 were changed to 10.0 parts of ethyltriethoxysilane and 20.0 parts of toluene were changed to 30.0 parts of toluene. A toner was produced in the same manner as in Example, and Toner 9 was obtained.

[Production Example of Toner 10]
Production of toner 1 except that 30.0 parts of methyltriethoxysilane used in the production example of toner 1 were changed to 15.0 parts of ethyltriethoxysilane and 20.0 parts of toluene were changed to 20.0 parts of methyl ethyl ketone. A toner was produced in the same manner as in Example, and Toner 10 was obtained.

[Production Example of Toner 11]
Toner 11 was prepared in the same manner as in Toner 1 except that 30.0 parts of methyltriethoxysilane used in Toner 1 were changed to 30.0 parts of n-propyltriethoxysilane. Obtained.

[Production Example of Toner 12]
Toner 12 was prepared in the same manner as in Toner 1 except that 30.0 parts of methyltriethoxysilane used in Toner 1 was changed to 30.0 parts of n-butyltriethoxysilane. Obtained.

[Production Example of Toner 13]
Toner 13 was obtained in the same manner as in Toner 6 except that 30.0 parts of methyltriethoxysilane used in Toner 6 were changed to 30.0 parts of ethyltriethoxysilane. .

[Production Example of Toner 14]
-Preparation of core particle composition mixture Styrene-n-butyl acrylate copolymer (Tg: 58 ° C, Mw: 22000) 100.0 parts Copper phthalocyanine (CI Pigment Blue 15: 3 (Daiichi Seikagaku ( 5.0 parts paraffin wax (trade name: HNP-7, manufactured by Nippon Seiki Co., Ltd.) 8.0 parts saturated polyester resin (terephthalic acid-propylene oxide modified bisphenol A copolymer, acid value: 13 mg KOH) / G, Mw: 14500) 5.0 parts Ethyl acetate 100.0 parts After pre-mixing the above materials in a container, the mixture was dispersed in a bead mill for 4 hours while keeping it at 20 ° C or lower, and a core particle composition A mixed solution was prepared.

・ Preparation of core particles 78 parts of 0.1 mol / L Na ₃ PO ₄ aqueous solution is added to 240 parts of ion-exchanged water, heated to 60 ° C., and a precision dispersion / emulsifier (trade name: M. Tech.) The mixture was stirred under the condition of a rotation speed of 14,000 rpm. To this, 12 parts of a 1.0 mol / L CaCl ₂ aqueous solution was added to obtain a dispersion medium (aqueous medium) containing Ca ₃ (PO ₄ ) ₂ . Furthermore, 1.0 part of carboxymethylcellulose (trade name: Serogen BS-H, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added and stirred for 10 minutes.

  While adjusting the temperature of the dispersion medium prepared in the container of the precision dispersing / emulsifying machine to 30 ° C. and stirring, 180 parts of the core particle composition mixed liquid whose temperature is adjusted to 30 ° C. is charged, After stirring for 1 minute, it is stopped to obtain a core particle composition dispersion suspension. While stirring the obtained core particle composition dispersion suspension, the temperature is kept constant at 40 ° C., the gas phase on the surface of the suspension is forcibly renewed by an exhaust device, and is kept for 17 hours. Removed. The obtained core particle dispersion was cooled, the supernatant was removed, and the concentration of the core particles in the dispersion was adjusted to 20% by mass.

  505.0 parts by mass (solid content: 100.0 parts by mass) of the above core particle dispersion was added with stirring 25.0 parts by mass of resin fine particle dispersion (particle size: 500 nm) (solid content: 5.0 parts by mass). Slowly added.

  Next, while raising the temperature of the oil bath for heating and maintaining the temperature at 55 ° C., 1 mol / L hydrochloric acid was dropped while slowly changing the pH of the dispersion, and the pH of the dispersion was adjusted to 1.5. After that, stirring was continued for 2 hours. Thereafter, a 1 mol / L aqueous sodium hydroxide solution was added dropwise with stirring until the pH of the dispersion reached 7.2.

  This dispersion was maintained at 65 ° C., which is higher than the glass transition temperature of the resin fine particles, and further stirred for 1 hour. After cooling the dispersion to 20 ° C., dilute hydrochloric acid was added until the pH reached 1.5. Further, after sufficiently washing with ion exchange water, filtration and drying were performed to obtain toner particles.

  The obtained toner particles were classified, and hydrophobic silica fine particles were externally added to the toner particles in the same manner as in the production example of the toner 1 to obtain a toner 14.

[Comparative Toner 1]
30.0 parts of methyltriethoxysilane used in the production example of toner 1 is 0.0 part of methyltriethoxysilane (= not used), and 20.0 parts of toluene is 0.0 part of toluene (= not used). A toner was manufactured in the same manner as in the manufacturing example of the toner 1 except that the toner was changed, and a comparative toner 1 was obtained.

[Production Example of Comparative Toner 2]
Production of resin dispersion Styrene 78.0 parts n-Butyl acrylate 20.0 parts Methacrylic acid 2.0 parts Dodecanethiol 6.0 parts Carbon tetrabromide 1.0 part Nonionic surfactant Nonipol 4001 in flask .5 parts and 2.5 parts of anionic surfactant Neogen SC were dissolved in 140 parts of ion-exchanged water.

  Next, 10 parts of ion-exchanged water in which 1.0 part of ammonium persulfate was dissolved was added thereto while the above materials were mixed and dissolved in a flask, emulsified and slowly mixed for 10 minutes. .

  Next, while performing nitrogen substitution, the flask was heated with an oil bath until the content reached 70 ° C., and emulsion polymerization was continued for 5 hours. As a result, a resin dispersion having a center diameter of 145 nm, Tg: 58 ° C., and Mw: 11200 was obtained.

・ Preparation of Blue Pigment Dispersion Solution The following materials were mixed and dissolved, and dispersed by ultrasonic irradiation with a homogenizer (trade name: Ultra Turrax) manufactured by IKA to obtain a blue pigment dispersion solution having a center particle size of 140 nm. .

Copper phthalocyanine (CI Pigment Blue 15: 3: manufactured by Dainichi Seika Kogyo Co., Ltd.) 100.0 parts Anionic surfactant Neogen SC 10.0 parts Ion-exchanged water 400.0 parts Preparation of mold release agent dispersion The following materials were mixed, heated to 97 ° C., and then dispersed with an IKA homogenizer (trade name: Ultra Turrax T50).

Paraffin wax (trade name: HNP-7, manufactured by Nippon Seiki Co., Ltd.) 100.0 parts Anionic surfactant Neogen SC 5.0 parts Ion-exchanged water 300.0 parts Thereafter, Gorin homogenizer (manufactured by Kyowa Shoji) And a dispersion treatment at 105 ° C. and 550 kg / cm ² was performed 20 times to obtain a release agent dispersion having a center diameter of 190 nm.

Toner particle production Resin dispersion (resin particle solid content 25.0 mass%) 400.0 parts Colorant dispersion (aromatic compound A content 11.0 mass%) 25.5 parts Release agent dispersion 30.0 parts Sanizol B50 2.0 parts The above materials were mixed and dispersed in a round stainless steel flask using Ultra Turrax T50, and then heated to 48 ° C while stirring the flask in an oil bath for heating. . Further, the temperature of the heating oil bath was raised and held at 50 ° C. for 1 hour. Thereafter, 3 parts of Neogen SC were added thereto. Thereafter, the stainless steel flask was sealed, heated to 105 ° C. while continuing stirring using a magnetic seal, and held for 3 hours. After cooling, it was filtered, washed with ion exchange water, and then dried to obtain toner particles.

  The obtained toner particles were classified, and hydrophobic silica fine particles were externally added to the toner particles in the same manner as in the production example of the toner 1 to obtain a comparative toner 2.

[Production Example of Comparative Toner 3]
Preparation of toner composition mixture Styrene-n-butyl acrylate copolymer (Tg 58 ° C., Mw 22000) 100.0 parts Copper phthalocyanine (CI Pigment Blue 15: 3, manufactured by Dainichi Seika Kogyo Co., Ltd.) 5 0.0 part paraffin wax (trade name: HNP-7, manufactured by Nippon Seiki Co., Ltd.) 8.0 parts saturated polyester resin (terephthalic acid-propylene oxide modified bisphenol A copolymer, acid value: 13 mg KOH / g, Mw: 14500) 5.0 parts ethyl acetate 100.0 parts The above materials were premixed in a container and then dispersed in a bead mill for 4 hours while maintaining the temperature at 20 ° C or lower to prepare a toner composition mixed solution.

Preparation of toner particles 78 parts of 0.1 mol / L Na ₃ PO ₄ aqueous solution is added to 240 parts of ion-exchanged water, heated to 60 ° C., and precision disperser / emulsifier manufactured by M Technique Co., Ltd. (trade name) : CLEARMIX) and stirred at a rotational speed of 14,000 rpm. To this, 12 parts of a 1.0 mol / L-CaCl ₂ aqueous solution was added to obtain a dispersion medium (aqueous medium) containing Ca ₃ (PO ₄ ) ₂ . Furthermore, 1.0 part of carboxymethylcellulose (trade name: Serogen BS-H, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added and stirred for 10 minutes.

While the temperature of the dispersion medium prepared in the container of the precision dispersing / emulsifying machine is adjusted to 30 ° C. and stirring, 180 parts of the toner composition mixed solution adjusted to a temperature of 30 ° C. is added. After stirring for a minute, the operation was stopped to obtain a toner composition dispersion suspension. While stirring the obtained toner composition dispersion suspension, the temperature is kept constant at 40 ° C., the gas phase on the surface of the suspension is forcibly renewed by an exhaust device, and is maintained for 17 hours to remove the solvent. did. After cooling to room temperature, hydrochloric acid was added to dissolve Ca ₃ (PO ₄ ) ₂ and filtered, washed with water and dried to obtain toner particles.

  The obtained toner particles were classified, and hydrophobic silica fine particles were externally added to the toner particles in the same manner as in the production example of the toner 1 to obtain a comparative toner 3.

[Production Example of Comparative Toner 4]
Styrene-n-butyl acrylate copolymer (Tg: 57 ° C., Mw: 21000) 100.0 parts Copper phthalocyanine (CI Pigment Blue 15: 3, manufactured by Daiichi Seika Kogyo Co., Ltd.) 5.0 parts Paraffin Wax (trade name: HNP-7, manufactured by Nippon Seiki Co., Ltd.) 3.0 parts Boric acid berylate compound (trade name: LR-147, manufactured by Nippon Carlit Co., Ltd.) 1.6 parts After premixing using Nippon Coke Kogyo Co., Ltd., the mixture was melt kneaded with a twin screw extruder, cooled, and coarsely pulverized to a particle size of about 1 to 2 mm using a hammer mill.

Subsequently, it was finely pulverized with an air jet type fine pulverizer.
Furthermore, the obtained finely pulverized product was classified with a multi-division classifier to obtain toner particles.
Comparative toner 4 was obtained by externally adding hydrophobic silica fine particles to the toner particles in the same manner as in the production example of toner 1.

[Production Example of Reference Toner 1]
Toner 1 was produced in the same manner as in Toner 1 except that 20.0 parts of toluene used in Toner 1 was changed to 0.0 parts of toluene (= not used), and Reference Toner 1 was obtained. It was.

[Production Example of Reference Toner 2]
Other than changing 30.0 parts of methyltriethoxysilane used in the production example of toner 1 to 30.0 parts of vinyltriethoxysilane, and changing 20.0 parts of toluene to 0.0 parts of toluene (= not used) Produced a toner in the same manner as in Production Example of Toner 1 to obtain Reference Toner 2.

  Table 1 shows the compositions and physical properties of Toners 1 to 14, Comparative Toners 1 to 4 and Reference Toners 1 to 2.

[Example 1]
<Evaluation of cleaning properties>
The toner cleaning property was evaluated as follows.

  In this evaluation, in order to evaluate the cleaning property of the toner, an electrophotographic photosensitive member having a configuration described later was used. This electrophotographic photosensitive member is not subjected to any surface treatment such as special measures against wear. However, the surface layer of the electrophotographic photosensitive member was provided only in the initial stage of image formation where the toner blocking layer was not formed so as to have a slipping property that does not cause chatter of the cleaning blade. Therefore, this evaluation shows the effect of maintaining the cleaning property by comparison between immediately after the start of image formation and after the end of image formation.

The structure of the electrophotographic photosensitive member is manufactured as follows.
That is, an aluminum cylinder having a diameter of 24.0 mm and a length of 357.0 mm was used as a support.

  Next, 10 parts of barium sulfate particles (conductive particles) coated with tin oxide, 2 parts of titanium oxide particles (resistance adjusting pigment), 6 parts of phenol resin (binder resin), silicone oil (leveling agent) 0. A conductive layer coating solution was prepared using a mixed solvent of 001 parts and methanol 4 parts / methoxypropanol 16 parts.

  The conductive layer coating solution was dip-coated on a support, and the resulting coating film was cured (heat cured) at 140 ° C. for 30 minutes to form a conductive layer having a thickness of 15 μm.

  Next, an undercoat layer coating solution was prepared by dissolving 3 parts of N-methoxymethylated nylon and 3 parts of copolymer nylon in a mixed solvent of 65 parts of methanol / 30 parts of n-butanol.

  This undercoat layer coating solution was dip-coated on the conductive layer, and the resulting coating film was dried at 100 ° C. for 10 minutes to form an intermediate layer having a thickness of 0.7 μm.

  Next, strong peaks at 7.5 °, 9.9 °, 16.3 °, 18.6 °, 25.1 ° and 28.3 ° with a Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction 10 parts of a crystalline form of hydroxygallium phthalocyanine (charge generation material) having 5 parts, and 5 parts of polyvinyl butyral resin (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd., binder resin) are dissolved in 250 parts of cyclohexanone. Added to the liquid. This was dispersed for 1 hour in an atmosphere of 23 ± 3 ° C. by a sand mill apparatus using glass beads having a diameter of 1 mm. After dispersion, a coating solution for charge generation layer was prepared by adding 250 parts of ethyl acetate.

  This charge generation layer coating solution was dip-coated on the intermediate layer and dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.26 μm.

  Next, 1 part of a compound (charge transport material) represented by the following formula (C1):

  9 parts of a compound (charge transport material) represented by the following formula (C2):

  10 parts of a polycarbonate resin having a structural unit represented by the following formula (B1) and having no siloxane structure at the end (weight average molecular weight Mw in terms of polystyrene: Mw: 100,000), and

  1 part of a polycarbonate resin having a structural unit represented by the above formula (B1) and having a structure represented by the following formula (B2) at the end (polystyrene equivalent weight average molecular weight Mw: 100,000)

Was dissolved in a mixed solvent of 20 parts of dimethoxymethane and 60 parts of orthoxylene to prepare a coating solution for charge transport layer.

  The charge transport layer coating solution was dip-coated on the charge generation layer, and the resulting coating film was dried at 120 ° C. for 1 hour to form a charge transport layer having a thickness of 15 μm.

  In this manner, an electrophotographic photoreceptor having a charge transport layer as a surface layer was produced.

  A modified machine in which the electrophotographic photosensitive member of the process cartridge of a laser beam printer (trade name: LBP7600) manufactured by Canon Inc. was changed to the electrophotographic photosensitive member produced above was used as an evaluation machine. The polyurethane cleaning blade for the laser beam printer was adjusted so that the contact angle with respect to the surface of the electrophotographic photosensitive member was 26 ° and the amount of penetration of the cleaning blade was 0.6 mm. The process speed was set to 180 mm / s.

The toner cartridge was filled with 100 g of toner 1. After leaving for 24 hours in an environment of low temperature and low humidity (10 ° C./15% RH), 2000 images with a 1.0% printing ratio were output. The cleaning property was evaluated by the occurrence of toner slipping from the cleaning blade when a solid image was output under the condition of 5.0% high printing after the initial image output and 2000 sheet image formation (image formation). The evaluation rank is as follows. The cleaning performance improves in the order of E, D, C, B, and A.
A: No toner slips.
B: Although it does not appear in the image, toner slips out. There is no risk of contamination of the charging member.
C: Although it does not appear in the image, toner passes through. There is a risk of contamination of the charging member.
D: The toner that appears in the image slips through.
E: Toner slipping through the image appears.

  When the toner was evaluated based on the above evaluation method and evaluation rank, the toner 1 of Example 1 had an initial evaluation of A rank, and then changed to a deteriorated photoconductor by a cleaning operation during printout. After that, it was excellent in cleanability and ranked A. The evaluation results are shown in Table 2.

[Examples 2 to 14]
The same evaluation as in Example 1 was performed except that the toner of Example 1 was changed from toner 1 to toners 2 to 14, respectively. The evaluation results are shown in Table 2.

  Among Examples 2 to 14, those having a cross-sectional shape close to a circle, unlike Example 1, may have a somewhat inferior cleaning property after outputting 2000 sheets of images because of a small external additive holding space.

[Comparative Examples 1-4]
The same evaluation as in Example 1 was performed, except that the toner of Example 1 was changed from toner 1 to comparative toners 1 to 4, respectively.

  The toners used in Comparative Examples 2 to 4 have a relatively irregular shape, and the initial evaluation was rank A. However, after outputting 2000 images, the result was rank D or E. This is because the fine irregularities on the surface are scarce, the external additive holding space is scarce, and the internal and external additives after image output are reduced, which increases the friction between the toner and the electrophotographic photosensitive member, and makes the cleaning blade This is probably because the amount of toner that slips through increased. The evaluation results are shown in Table 2.

[Reference Examples 1-2]
The same evaluation as in Example 1 was performed, except that the toner of Example 1 was changed from Toner 1 to Reference Example Toners 1 and 2, respectively. The evaluation results are shown in Table 2.

DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor 2 Axis 3 Charging means 4 Exposure light 5 Developing means 6 Transfer means 7 Cleaning means 8 Fixing means 9 Process cartridge 10 Guide means P Transfer material

Claims (7)

A toner manufacturing method for manufacturing a toner having toner particles and an external additive ,
As a step for producing the toner particles, it viewed including the following steps 1,
Step 1: Form polymerizable monomer composition particles containing a polymerizable monomer, a colorant, a release agent, an organic solvent and an organosilicon monomer in an aqueous medium, and the polymerizable monomer And the step of polymerizing each of the organosilicon monomers and removing the organic solvent :
The polymerizable monomer composition contains the organic solvent in an amount of 60 parts by mass to 100 parts by mass with respect to 100 parts by mass of the organosilicon monomer.
The toner particles have a shape factor SF1 of a cross section formed by a cross section polisher cross section method (CP cross section method) of 100 or more and 250 or less, and a value of the shape factor SF2 of the cross section is 350 or more. A method for producing toner. The method for producing a toner according to claim 1 , wherein the organosilicon monomer is an organosilicon monomer represented by the following formula (1).

(In Formula (1), R ¹ represents a hydrocarbon group selected from the group consisting of an alkyl group, a vinyl group, and an allyl group. R ^{2 to} R ⁴ each independently represents a hydroxy group, an alkoxy group, an acetoxy group, A reactive group selected from the group consisting of a group and a halogen atom.) The toner manufacturing method according to claim 2, wherein the organosilicon monomer is an alkoxysilane compound. The toner production according to claim 3 , wherein the alkoxysilane compound is at least one selected from the group consisting of methyltriethoxysilane, ethyltriethoxysilane, n-propyltriethoxysilane, and n-butyltriethoxysilane. Method. The toner manufacturing method according to claim 4 , wherein the alkoxysilane compound is methyltriethoxysilane. Wherein the organic solvent is toluene, method for producing a toner according to any one of claims 1 to 5 is at least one selected from the group consisting of methyl cyclohexane and methyl ethyl ketone. The toner particles, as a binder resin, and a styrene monomer, of claims 1 to 6 containing a copolymer of at least one selected from the group consisting of acrylic acid esters and methacrylic acid esters The method for producing a toner according to any one of the above items.

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