JP5159252B2 - Toner and image forming method - Google Patents

Description

  The present invention relates to a toner used in a recording method using electrophotography or the like, and an image forming method.

  Many methods are known as electrophotographic methods. Generally, an electrostatic latent image is formed on an electrostatic charge image carrier (hereinafter also referred to as a “photosensitive member”) by using a photoconductive substance by various means. Form. Next, the latent image is developed with toner to form a visible image, and if necessary, the toner image is transferred to a recording medium such as paper, and then the toner image is fixed on the recording medium by heat or pressure, etc. Is what you get. Examples of such an image forming apparatus include a copying machine and a printer.

  These printers and copiers have recently moved from analog to digital, and there is a strong demand for higher speed and smaller size as well as excellent reproducibility of latent images and high resolution.

  Here, when attention is paid to downsizing, it is an indispensable condition for downsizing the diameter of the latent image carrier, toner carrier, etc. in the image forming process. In addition, by reducing the diameter of the toner carrier, the number of contact between the toner and the toner layer thickness regulating member is increased, a uniform charge amount is obtained, and the coat state of the toner carrier is uniform, so that improvement in image quality is expected. it can.

  However, an increase in the curvature of the toner carrier means that the contact area with the toner layer thickness regulating member is reduced. Therefore, the pressure concentrates on the toner between the regulating member and the carrier, and this causes a problem that toner deterioration is promoted. In particular, in a severe environment with respect to toner deterioration such as in a high temperature environment, development streaks due to scratches on the toner carrier and toner fusion are likely to occur. In addition, the development amount of toner tends to decrease as the development area narrows. Therefore, in an environment where the chargeability is likely to be lowered such as a humid environment, the image density is likely to be lowered after long-term use.

  As described above, when a small-diameter toner carrier is used, miniaturization and image quality are improved, but problems such as image density and development streak occur.

  Attempts have been made to improve the problems by controlling the surface composition of the toner. For example, the relationship between the amount of carbon and oxygen measured by ESCA (Patent Documents 1, 2, and 6) and the amount of displacement compressed when a load is applied to one particle of toner and the load are within a specific range. There are specified ones (Patent Document 3 and Patent Document 4). In addition, a load-displacement curve obtained by performing a micro-compression test of one particle of toner is adjusted (Patent Document 5). However, these techniques still have room for improvement in improving image density and developing streaks when combined with a small-diameter toner carrier.

JP 2004-157423 A JP 2007-108675 A Japanese Patent No. 0300318 Japanese Patent No. 03391931 JP-A-2005-300937 JP 2007-108675 A

  The present invention has been made in view of the above-mentioned problems of the prior art. When a small-diameter toner carrier is used, a thin image density and development streaks occur in a high-temperature and high-humidity environment. This is the problem to be solved by the present invention.

The present invention relates to a charging process in which a voltage is applied to a charging member to charge an image carrier, an electrostatic latent image forming process in which image information is written as an electrostatic latent image on the charged image carrier, and an outer surface for carrying toner. A toner layer thickness regulating member is brought into contact with a toner carrier having a diameter of 8.0 mm or more and less than 12.0 mm to form a toner layer on the toner carrier, and the image carrier and the toner carrier are fixed to each other. A step of forming a developing portion by disposing the gap and transferring a toner to the electrostatic latent image to form a toner image in the developing portion to which an alternating electric field is applied; and And a transfer step for transferring to a recording medium, and a toner used in an image forming method in which image formation is repeatedly performed on an image carrier,
The toner contains at least a binder resin, a magnetic material, and a wax;
The mode circularity measured by the flow type particle image measuring device of the toner is 0.975 or more,
The peak area of carbon atoms is 88.0% or more and 95.0% or less with respect to the total peak area measured by ESCA (X-ray photoelectron spectroscopy) of the toner, and the peak area of oxygen atoms is 5.0. % To 12.0%,
In the micro-compression test for the toner, the maximum value of the maximum displacement obtained when 100 particles of toner are selected and a load of 9.8 × 10 ⁻⁴ N / sec is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec. The present invention relates to a toner characterized in that a difference in minimum values is 1.5 μm or less.

The present invention also includes a charging step of applying a voltage to the charging member to charge the image carrier, an electrostatic latent image forming step of writing image information as an electrostatic latent image on the charged image carrier, and carrying toner. A toner layer thickness regulating member is brought into contact with a toner carrier having an outer diameter of 8.0 mm or more and less than 12.0 mm to form a toner layer on the toner carrier, and the image carrier and the toner carrier are formed. A step of forming a developing portion by arranging at a predetermined interval, and transferring a toner image to the electrostatic latent image to form a toner image in the developing portion to which an alternating electric field is applied; and the toner A transfer process for transferring an image to a recording medium, and an image forming method in which image formation is repeatedly performed on an image carrier,
The toner contains at least a binder resin, a magnetic material, and a wax;
The mode circularity measured by the flow type particle image measuring device of the toner is 0.975 or more,
The peak area of carbon atoms is 88.0% or more and 95.0% or less with respect to the total peak area measured by ESCA (X-ray photoelectron spectroscopy) of the toner, and the peak area of oxygen atoms is 5.0. % To 12.0%,
In the micro-compression test for the toner, the maximum value of the maximum displacement obtained when 100 particles of toner are selected and a load of 9.8 × 10 ⁻⁴ N / sec is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec. The present invention relates to an image forming method characterized in that the difference between the minimum values is 1.5 μm or less.

  Even in combination with a small-diameter toner carrier, the image density is high, and a clear image without development streaks can be provided.

The toner according to the present invention includes a charging step of applying a voltage to the charging member to charge the image carrier, an electrostatic latent image forming step of writing image information as an electrostatic latent image on the charged image carrier, and a toner carrying A toner layer thickness regulating member is brought into contact with a toner carrier having an outer diameter of 8.0 mm or more and less than 12.0 mm to form a toner layer on the toner carrier, and the image carrier and the toner carrier are formed. A step of forming a developing portion by arranging at a predetermined interval, and transferring a toner image to the electrostatic latent image to form a toner image in the developing portion to which an alternating electric field is applied; and the toner A toner used in an image forming method in which an image is repeatedly formed on an image carrier, and the toner includes at least a binder resin, a magnetic material, and a wax. Containing The mode circularity measured by the flow type particle image measuring apparatus is 0.975 or more, and the peak area of carbon atoms is larger than the total peak area measured by ESCA (X-ray photoelectron spectroscopy) of the toner. It is 88.0% or more and 95.0% or less, and the peak area of oxygen atom is 5.0% or more and 12.0% or less. In the micro-compression test for the toner, 100 particles of toner are selected, and the loading speed is 9 A toner characterized in that the difference between the maximum value and the minimum value of the maximum displacement obtained when a load of 9.8 × 10 ⁻⁴ N is applied at .8 × 10 ⁻⁵ N / sec is 1.5 μm or less. is there.

  This is a case where a small-diameter toner carrier is used, but as described above, the development area is reduced, so the toner development amount is reduced, and the image density is likely to be lowered. Further, since the curvature of the toner carrier is high, the contact pressure of the toner regulating member is increased and development streaks are likely to occur.

Therefore, as a result of repeated investigations in terms of both improving developability and suppressing development streaks when using a small-diameter toner carrier,
(1) The mode circularity of the toner is 0.975 or more,
(2) The peak area of carbon atoms is 88.0% or more and 95.0% or less, and the peak area of oxygen atoms is 5.0% or more and 12.0% with respect to the total peak area measured by ESCA of the toner. % Or less,
(3) In the micro-compression test for the toner, the maximum displacement amount obtained when 100 particles of toner are selected and a load of 9.8 × 10 ⁻⁴ N is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec. The present inventors have found that the above problem can be solved by adjusting the difference between the maximum value and the minimum value to 1.5 μm or less, and have reached the present invention.

  First, the mode circularity of the toner (1) will be described. The mode circularity in this invention has shown the mode value of circularity distribution obtained by measuring with the flow type particle image analyzer FPIA3000 (made by Sysmex Corporation). The larger the mode circularity, the sharper the toner charge amount distribution and the higher the developability. For this purpose, it is important that the mode circularity of the toner is 0.975 or more. When the mode circularity is less than 0.975, the developability of the toner is insufficient and the image density tends to decrease. When the mode circularity is controlled and the standard deviation of the circularity is 0.040 or less, the shape of the toner becomes uniform and the charge amount distribution is further sharpened, which is more preferable.

  Next, the peak areas of carbon and oxygen atoms measured by ESCA of the toner (2) will be described. According to the study by the present inventors, when a toner carrier having a small diameter less than 12 mm is used, the development area becomes narrow as described above, and the density is not easily obtained. For this reason, from the viewpoint of development efficiency, it was found that the image density can be increased if a certain amount of wax is present on the toner surface. This is presumably because the wax on the toner surface improves the releasability from the toner carrier, thereby improving the development efficiency and leading to a high image density. However, when the amount of the wax on the surface is excessive, development streaks due to the fusion of the wax on the toner carrier may occur under severe conditions such as long-term use in a high-temperature environment using a small-diameter toner carrier. Will occur. Therefore, there is an appropriate range for the amount of surface wax, and it is important to control the ratio of the resin and wax on the toner surface.

  The surface wax amount can be known by measuring the outermost surface of the toner by ESCA. ESCA can quantify the amount of elements on the outermost surface of the toner, and can determine the presence state of each material on the outermost surface of the toner from the amount of elements measured there. In the present invention, the carbon atoms measured by ESCA are derived from the wax and binder resin present on the toner surface. However, since wax is a material having carbon as a main element, it can be said that a large amount of wax exists on the surface when the carbon peak on the toner surface is strong. On the other hand, the peak of oxygen atoms is also derived from the wax and the binder resin, but the ratio of oxygen atoms in the wax to the resin is small. Therefore, it can be said that the peak of oxygen atoms is mainly attributable to the resin. From these facts, it is considered that the peak areas of carbon atoms and oxygen atoms on the toner surface are correlated with the amount of wax on the toner surface.

  According to the study by the present inventors, the peak area of carbon atoms is 88.0% or more and 95.0% or less with respect to the total peak area measured by ESCA, and the peak area of oxygen atoms is 5.0%. It is important that the content is 12.0% or less. Within this range, the binder resin and wax are present in an appropriate ratio on the toner surface, and a toner having excellent developability can be obtained even when a small-diameter toner carrier is used. When the peak area of the carbon atom is less than 88.0%, the releasability of the toner is insufficient, and the development efficiency is insufficient, so that the density tends to decrease during long-term use in a high temperature environment. On the other hand, if it exceeds 95.0%, the amount of wax on the toner surface becomes excessive, and fusing to the toner carrying member occurs, resulting in deterioration of development streaks. On the other hand, if the peak area of the oxygen atom is less than 5.0%, the amount of wax on the toner surface is excessive, so that fusion to the toner carrier occurs, and the development streak deteriorates. When the peak area of the oxygen atom exceeds 12.0%, the amount of wax on the toner surface is insufficient, so that the releasability from the toner is insufficient and the image density tends to decrease. When the peak area of the carbon atom is 89.0% or more and 94.0% or less, the effect is remarkable and more preferable.

  Further, when the charging performance of the toner is made uniform by (1), the triboelectric charge amount of the toner on the small-diameter toner carrier becomes uniform, and the bias followability is remarkably improved. Furthermore, the development efficiency can be greatly improved by the synergistic effect of enhancing the releasability between the toner and the toner carrier by (2). Therefore, even when the development area is narrow, selective development is not performed, and a high image density can be obtained even in the latter half of the durability.

Next, the difference between the maximum value and the minimum value of the maximum displacement amount in the micro compression test (3) will be described. It is considered that the development streaks are generated when the toner on the toner carrier is excessively loaded and the brittle toner is cracked and fused, or conversely, too hard toner damages the toner carrier. Therefore, the present inventors focused on the hardness of the toner and thought whether the development streak could be improved by optimizing it. According to the examination results of the present inventors, it has been important to control the degree of deformation of the toner to be constant when a force greater than the load applied to the toner in the developing process is applied to the toner. Specifically, the difference between the maximum value and the minimum value of the maximum displacement obtained when a load of 9.8 × 10 ⁻⁴ N is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec in the micro compression test is 1. It is to adjust to 5 μm or less. The force of 9.8 × 10 ⁻⁴ N corresponds to several tens of times the force that the toner on the toner carrier receives from the toner regulating member. By controlling the deformation of the toner when such an excessive load is applied, development streaks can be prevented even in locations and situations where the contact pressure of the toner regulating member is extremely increased.

  When the difference between the maximum value and the minimum value of the maximum displacement exceeds 1.5 μm, the hardness of the toner becomes non-uniform, and development streaks due to fusing of the broken toner and scraping of the toner carrier are likely to occur. . Therefore, it is important that the difference between the maximum value and the minimum value of the maximum displacement amount is 1.5 μm or less, and more preferably 1.3 μm or less.

  Further, when the shape is controlled to be nearly spherical as in (1), the unevenness is reduced, so that it is possible to prevent the share from being concentrated on the convex portion. Further, when the hardness is made uniform as in (3), there is no difference in strength between individual toners, so that only brittle toner is not crushed. Therefore, even in a situation where a large share is applied to the toner, scratches and fusion to the toner carrying member are hardly generated.

  In the present invention, the toner charge distribution sharpening by the mode circularity control (1) as described above, the releasability from the toner carrier by the toner surface composition control (2), and the toner of (3) Uniformity of the hardness is important, and the object of the present invention has been achieved by the synergistic effect of (1), (2), and (3).

  The toner of the present invention contains at least a binder resin, a magnetic material, and wax. Hereinafter, materials that can be particularly suitably used for the toner of the present invention will be described.

  The binder resin used in the toner of the present invention is preferably mainly composed of a hybrid resin having a polyester unit and a vinyl copolymer unit. The “hybrid resin” here refers to a resin in which a polyester unit and a vinyl polymer unit are chemically bonded. The hybrid resin component can easily control the presence state of the wax surface and the hardness of the toner, and can be controlled within the appropriate range as described above. Therefore, by using the hybrid resin, it is possible to improve the development efficiency by improving the releasability from the toner carrier and to prevent the toner carrier from being scratched or fused due to the uniform hardness. Therefore, it is possible to further improve the durability developability and suppress development streaks.

  Furthermore, it is preferable that the polyester unit is composed mainly of a polyester unit condensed with at least a fatty acid tin salt as a catalyst. When a fatty acid tin salt is used as a catalyst, the resin composition tends to be uniform, and the hardness after toner formation tends to be uniform. Therefore, a great effect can be seen for development streaking suppression. The term “main component” as used herein refers to a component that occupies 70% by mass or more of the total amount of binder resin in the toner.

  In the toner of the present invention, selection of the wax to be used is also important. The wax is preferably composed mainly of an aliphatic hydrocarbon wax having a melting point of 80 ° C. or higher and 150 ° C. or lower. When the above-mentioned wax is selected, the amount of wax on the toner surface can be easily controlled, and the mold release effect when present on the surface is excellent. Further, the presence state of the wax tends to be uniform, and accordingly, the hardness of the toner surface is also easily uniformed. Therefore, development streak and durability developability can be improved. When the melting point is less than 80 ° C., the wax on the toner surface is fused to the toner carrying member to inhibit frictional charging, so that there is a tendency for development streaks and image density to decrease. On the other hand, when the melting point exceeds 150 ° C., the releasability from the toner carrier is small and the development efficiency is lowered, so that the image density tends to be lowered. Here, “main component” refers to a component that occupies 70% by mass or more of the total amount of wax in the toner.

  Examples of materials and production methods that can be used in the present invention are shown below.

  An arbitrary binder resin can be used for the toner of the present invention. However, when the main component is a hybrid resin having a polyester unit and a vinyl copolymer unit, development streaks are suppressed as described above. From the viewpoint of durable developability, it is preferable.

  In the method for producing a hybrid resin, a raw material monomer of a condensation polymerization resin, a raw material monomer of an addition polymerization resin, an amphoteric compound, a release agent, etc. are mixed, and first, by radical polymerization reaction at 50 ° C. or higher and 180 ° C. or lower. An addition polymerization resin component having a functional group capable of condensation polymerization is obtained. Next, after raising the reaction temperature from 190 ° C. to 270 ° C., it is preferable to form a condensation polymerization resin component mainly by a condensation polymerization reaction.

  Further, the polycondensation reaction is preferably performed in the presence of a catalyst from the viewpoint of the uniformity of the resin obtained. In particular, the use of a fatty acid tin salt is preferable because the uniformity of the hardness of the resin is high as described above, and the effect of improving the development streak can be obtained. Examples of the fatty acid tin salt include tin (II) carboxylates and dialkoxytin (II) having 2 to 28 carbon atoms. Examples of these are shown below.

  As tin (II) carboxylate having 2 to 28 carbon atoms, tin (II) oxalate, tin (II) acetate, tin (II) octoate, tin (II) laurate, tin (II) stearate, olein Examples thereof include tin (II) acid.

  Examples of dialkoxytin (II) having 2 to 28 carbon atoms include dioctyloxytin (II), dilauroxytin (II), distearoxytin (II), and dioleoxytin (II).

  Fatty acid tin (II) having 6 to 20 carbon atoms is more preferable, and saturated fatty acid tin (II) having 8 to 18 carbon atoms is particularly preferable.

  The binder resin containing the hybrid resin component as a main component is produced using a polyester resin monomer, a vinyl resin monomer, a compound capable of reacting with any of them, and the like. As the monomer of the polyester resin, a divalent or trivalent or higher valent carboxylic acid component such as a divalent or trivalent or higher alcohol and a carboxylic acid, or a carboxylic acid anhydride or a carboxylic acid ester is used.

  A dihydric alcohol is illustrated below. For example, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene ( 2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, poly Alkylene oxide adducts of bisphenol A such as oxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol 1,4-butanediol, neopentyl glycol, 1,4-butene All, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, propylene adduct of bisphenol A, bisphenol An ethylene adduct of A, hydrogenated bisphenol A, etc. are mentioned.

  Examples of the trivalent or higher alcohols include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1 , 2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. It is done. Among these alcohols, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane are Preferably used. These dihydric alcohol monomers and trihydric or higher polyhydric alcohol monomers can be used alone or in combination.

  The acid component is a carboxylic acid component and a divalent monomer such as maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, Sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, isooctyl succinic acid Examples include acids, anhydrides of these acids, and lower alkyl esters. Of these divalent carboxylic acid components, maleic acid, fumaric acid, terephthalic acid, isododecenyl succinic acid, and anhydrides or lower alkyl esters of these acids are preferably used.

  Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and 1,2,4-butanetricarboxylic acid. 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7 , 8-octanetetracarboxylic acid, pyromellitic acid, emporic trimer acid, their acid anhydrides, lower alkyl esters and the like. Among these, in particular, 1,2,4-benzenetricarboxylic acid, that is, trimellitic acid or its derivative, is inexpensive and easy to control, so that it is preferably used. These divalent carboxylic acid monomers and trivalent or higher polyvalent carboxylic acid monomers can be used alone or in combination.

On the other hand, as monomers for vinyl resins, those exemplified below can be used.
Styrene or styrene derivatives such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-chlorostyrene, vinylnaphthalene.
-Ethylenically unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene.
-Vinyl esters such as vinyl chloride, vinyl bromide, vinyl iodide, vinyl acetate, vinyl propionate, vinyl formate, and vinyl caproate.
-Acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, amyl acrylate, cyclohexyl acrylate, n-acrylate Octyl, isooctyl acrylate, decyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, methoxyethyl acrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl chloroacrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, meta Tert-butyl silylate, amyl methacrylate, cyclohexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, decyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methoxyethyl methacrylate, methacrylic acid 2 -Ethylenic monocarboxylic acids such as hydroxyethyl, glycidyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and esters thereof.
-Substituted ethylenic monocarboxylic acid such as acrylonitrile, methacrylonitrile, acrylamide.
-Ethylene dicarboxylic acid such as dimethyl maleate and its substitutes.
-Vinyl ketones such as vinyl methyl ketone.
-Vinyl ethers such as vinyl ethyl ether.
-Vinylidene halides such as vinylidene chloride.

  Among these, since the dispersibility of the wax is good, a combination of styrene and acrylic acid or an ester thereof, or a combination of styrene and methacrylic acid or an ester thereof is preferably used.

  Moreover, a crosslinking agent can also be used as needed, for example, divinylbenzene, divinylnaphthalene, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, 1,6. -Hexylene glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4-methacryloxydiethoxyphenyl) propane, 2,2'-bis (4- Acryloxydiethoxyphenyl) propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate Dibromo neopentyl glycol dimethacrylate, etc. diallyl phthalate, (a combination of two or more if necessary) a general crosslinking agent suitably may be used. Preferably, divinylbenzene or polyethylene glycol dimethacrylate is used.

  Examples of polymerization initiators used for polymerization of vinyl resin monomers include 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1 ′. -Azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, other azo or diazo polymerization initiators or benzoyl peroxide, methyl ethyl ketone peroxide, isopropyl Examples of the peroxide polymerization initiator include peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, and dicumyl peroxide. These polymerization initiators can be used alone or in combination.

  In order to obtain a hybrid resin component having a polyester unit and a vinyl copolymer unit, polymerization is performed using a compound capable of reacting with any of the monomers of both resins (hereinafter referred to as “both reactive compounds”). Examples of such a bireactive compound include compounds such as fumaric acid, acrylic acid, methacrylic acid, citraconic acid, maleic acid, and dimethyl fumarate in the polyester resin monomer and the vinyl resin monomer. . Of these, fumaric acid, acrylic acid, and methacrylic acid are preferably used.

Next, the toner of the present invention contains a wax. In the toner of the present invention, any wax can be used, but an aliphatic hydrocarbon wax having a melting point of 80 ° C. or higher and 150 ° C. or lower is preferred as a main component from the viewpoint of development streak and durable developability. Below, the wax which can be used is illustrated.
-Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax.
-Oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof.
-Waxes based on fatty acid esters such as carnauba wax, sazol wax, and montanic acid ester wax.
・ Deoxidized part or all of fatty acid esters such as deoxidized carnauba wax.
・ Saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid.
・ Unsaturated fatty acids such as brassic acid, eleostearic acid and valinalic acid, stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol and other saturated alcohols, and polyhydric alcohols such as sorbitol .
-Fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide.
-Saturated fatty acid bisamides such as methylene bis stearamide, ethylene biscapric amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide.
Unsaturated fatty acid amides such as ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide.
-Aromatic bisamides such as m-xylenebisstearic acid amide and N, N'-distearylisophthalic acid amide.
-Aliphatic metal salts such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate (generally referred to as metal soap).
-Waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid.
-A methyl ester compound having a hydroxyl group, obtained by partial esterification of a fatty acid and a polyhydric alcohol, such as behenic acid monoglyceride, hydrogenation of vegetable oils and the like.
-Long chain alkyl alcohol or long chain alkyl carboxylic acid having 12 or more carbon atoms.

The toner of the present invention contains a magnetic substance. The magnetic material used in the toner of the present invention is mainly composed of magnetic iron oxide such as triiron tetroxide and γ-iron oxide, and includes phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum, silicon, and the like. An element may be included. These magnetic materials preferably have a BET specific surface area of 2 to 30 m ² / g by a nitrogen adsorption method. The magnetization intensity of the magnetic material is preferably 30 to 120 Am ² / kg at a magnetic field of 79.6 kA / m.

  The magnetic material used in the toner of the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. While maintaining the pH of the prepared aqueous solution at pH 7 or higher, heating the aqueous solution to 70 ° C. or higher, performing an oxidation reaction of ferrous hydroxide while blowing air, and forming a seed crystal that becomes the core of the magnetic iron oxide powder First generate.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. While maintaining the pH of the solution at 5 to 10, the reaction of ferrous hydroxide proceeds while blowing air to grow a magnetic iron oxide powder with the seed crystal as a core. At this time, it is possible to control the shape and magnetic characteristics of the magnetic material by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5. A magnetic material can be obtained by filtering, washing, and drying the magnetic material thus obtained by a conventional method.

  In the present invention, other colorants may be used in addition to the magnetic substance. Examples of the colorant that can be used in combination include magnetic or nonmagnetic inorganic compounds in addition to the above-described known dyes and pigments. Specifically, ferromagnetic metal particles such as cobalt and nickel, or alloys obtained by adding chromium, manganese, copper, zinc, aluminum, rare earth elements to these, particles such as hematite, titanium black, nigrosine dye / pigment, carbon Examples thereof include black and phthalocyanine.

  In the toner of the present invention, a charge control agent may be blended as necessary to improve charging characteristics. A well-known thing can be utilized as a charge control agent. Among charge control agents, specific compounds as negative charge control agents include metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid, azo dyes or metal salts of azo pigments. Alternatively, a metal complex, a polymer compound having a sulfonic acid or carboxylic acid group in the side chain, a boron compound, a urea compound, a silicon compound, calixarene, and the like can be given. Examples of the positive charge control agent include quaternary ammonium salts, polymer compounds having the quaternary ammonium salt in the side chain, guanidine compounds, nigrosine compounds, imidazole compounds, and the like.

  The amount of these charge control agents used is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. However, when added internally to the toner particles, it is preferably used in an amount of 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the binder resin. In addition, when externally added to the toner particles, the amount is preferably 0.005 parts by mass or more and 1.000 parts by mass or less with respect to 100 parts by mass of the toner.

  The glass transition temperature (Tg) of the toner of the present invention is preferably 40 ° C. or higher and 70 ° C. or lower. When the glass transition temperature is less than 40 ° C., the storage stability is lowered, and the toner is liable to deteriorate during long-term use. When the glass transition temperature is higher than 70 ° C., the fixing property is deteriorated.

  A fluidity improver may be added to the toner of the present invention. The fluidity improver can be added to the toner particles to increase the fluidity before and after the addition. Examples of such fluidity improvers include, for example, fluororesin powder such as vinylidene fluoride fine powder, polytetrafluoroethylene fine powder, wet process silica, fine powder silica such as dry process silica, and fine powder titanium oxide. , Fine powder alumina, treated silane compound, titanium coupling agent, fine powder treated with silicone oil, oxides such as zinc oxide and tin oxide, strontium titanate, barium titanate, calcium titanate, zircon Examples thereof include double oxides such as strontium acid and calcium zirconate, calcium carbonate, and carbonate compounds such as magnesium carbonate.

  The toner of the present invention can be used as a one-component developer by further mixing with other external additives (for example, a charge control agent, etc.) if necessary, and can also be used as a two-component developer in combination with a carrier. Can do. As the carrier for use in the two-component development method, all conventionally known carriers can be used. Specifically, surface oxidized or unoxidized iron, nickel, cobalt, manganese, chromium, rare earth, etc. Particles having an average particle size of 20 μm or more and 300 μm or less, such as metals and their alloys or oxides, are preferably used.

  The toner production method according to the present invention will be described in detail below.

  In order to produce the toner according to the present invention, the following production method is preferably used. First, arbitrary toner constituent materials are sufficiently mixed by a ball mill or other mixer, and then kneaded well using a heat kneader such as a hot roll, kneader, extruder, etc., cooled and solidified, then finely pulverized, Toner particles are obtained by classification. Further, the obtained toner particles are subjected to surface modification using a surface modification apparatus. If necessary, desired additives are sufficiently mixed by a mixer such as a Henschel mixer to obtain a toner.

  A preferred method for modifying the surface of the toner particles is to apply heat to the toner particles in the air layer. For example, there is a method in which high-temperature hot air is instantaneously blown onto the surface of the toner particles, and immediately after that, the toner particles are instantaneously cooled with cold air. Modifying the surface of the toner particles by such a technique does not apply excessive heat to the toner particles. Therefore, it is possible to modify the surface of the toner particles while preventing deterioration of the raw material components. When high-temperature hot air is blown, the vicinity of the surface of the toner particles is instantaneously melted, and the wax in the toner particles can easily exude to the surface. Further, since the toner is instantaneously cooled in that state, toner particles in which the amount of wax present on the surface and the state of presence are controlled can be obtained. As such an apparatus, for example, Meteorebombo (manufactured by Nippon Pneumatic Industry Co., Ltd.) can be mentioned.

  The toner of the present invention can be manufactured using a known manufacturing apparatus. For example, the following manufacturing apparatus can be used depending on the situation.

  For example, Henschel mixer (Mitsui Mining Co., Ltd.), super mixer (Kawata Co., Ltd.), ribocorn (Okawara Seisakusho Co., Ltd.), Nauter mixer, turbulizer, cyclomix (Hosokawa Micron Co., Ltd.), spiral pin mixer (Manufactured by Taiheiyo Kiko Co., Ltd.), Redige mixer (manufactured by Matsubo), and the like.

  As a kneader, for example, KRC kneader (manufactured by Kurimoto Iron Works), Bus Co Kneader (manufactured by Buss), TEM type extruder (manufactured by Toshiba Machine), TEX twin-screw kneader (manufactured by Nippon Steel Works) , PCM kneader (Ikegai Iron Works Co., Ltd.), three roll mill, mixing roll mill, kneader (Inoue Seisakusho Co., Ltd.), kneedex (Mitsui Mining Co., Ltd.), MS pressure kneader, Nidar Ruder (Moriyama Seisakusho Co., Ltd.) , Banbury mixer (manufactured by Kobe Steel).

  Examples of the pulverizer include counter jet mill, micron jet, inomizer (manufactured by Hosokawa Micron), IDS type mill, PJM jet pulverizer (manufactured by Nippon Pneumatic Industrial Co., Ltd.), cross jet mill (manufactured by Kurimoto Iron Works), ULMAX (Nisso Engineering Co., Ltd.), SK Jet O-Mill (Seishin Enterprise Co., Ltd.), Cryptron (Kawasaki Heavy Industries Co., Ltd.), Turbo Mill (Turbo Industry Co., Ltd.), Super Rotor (Nisshin Engineering Co., Ltd.) It is done.

  Classifiers include, for example, a class seal, a micron classifier, a speck classifier (manufactured by Seishin Enterprise Co., Ltd.), a turbo classifier (manufactured by Nissin Engineering Co., Ltd.), a micron separator, a turboplex (ATP), and a TSP separator (manufactured by Hosokawa Micron Co., Ltd.) ), Elbow jet (manufactured by Nippon Steel Mining Co., Ltd.), dispersion separator (manufactured by Nippon Pneumatic Industrial Co., Ltd.), YM micro cut (manufactured by Yaskawa Shoji Co., Ltd.), and the like.

  Examples of sieving devices used to screen coarse particles include Ultrasonic (manufactured by Sakae Sangyo Co., Ltd.), Resona Sieve, Gyroshifter (Tokuju Kosakusha Co., Ltd.), Vibrasonic System (manufactured by Dalton Co., Ltd.), Soniclean (new) East Industrial Co., Ltd.), turbo screener (Turbo Kogyo Co., Ltd.), micro shifter (Ogino Sangyo Co., Ltd.), circular vibrating sieve, and the like.

  Next, an example of an image forming apparatus that can suitably use the toner of the present invention will be specifically described with reference to FIG. In FIG. 1, reference numeral 100 denotes an electrostatic latent image carrier (hereinafter also referred to as a photoconductor), which includes a charging roller 117, a developing device 140 having a toner carrier 102, a transfer charging roller 114, a cleaner 116, and a register roller. 124 etc. are provided. The electrostatic latent image carrier 100 is charged to, for example, −600 V by the charging roller 117 (applied voltages are, for example, an AC voltage of 1.85 kVpp and a DC voltage of −620 Vdc). Then, exposure is performed by irradiating the electrostatic latent image carrier 100 with the laser beam 123 by the laser generator 121, and an electrostatic latent image corresponding to the target image is formed. The electrostatic latent image on the electrostatic latent image carrier 100 is developed with a one-component toner by the developing device 140 to obtain a toner image, and the toner image is transferred in contact with the electrostatic latent image carrier via a transfer material. The image is transferred onto the transfer material by the roller 114. The transfer material on which the toner image is placed is conveyed to the fixing device 126 by the conveying belt 125 or the like and fixed on the transfer material. In addition, the toner remaining on the electrostatic latent image carrier is partially cleaned by the cleaner 116.

  The charging step in the image forming method of the present invention includes an electrostatic latent image carrier that is a member to be charged and an image carrier, and a conductive type such as a roller type (charging roller), a fur brush type, and a blade type (charging blade). A contact charging device is used in which a contact portion is formed and brought into contact with the charging member, and a predetermined charging bias is applied to the contact charging member to charge the surface of the electrostatic latent image carrier to a predetermined polarity and potential. Further, by performing contact charging in this way, stable and uniform charging can be performed, and further, there is an effect that generation of ozone is reduced.

  However, in general, when a fixed type charging member is used, it is difficult to maintain uniform contact between the charging member and the rotating image carrier, and uneven charging tends to occur. For this reason, it is more preferable to use a charging member (charging roller) that rotates in the same direction as the image carrier in order to maintain uniform contact with the image carrier and perform uniform charging.

  As a preferable process condition when the charging roller is used, the contact pressure of the roller is 4.9 to 490.0 N / m (5.0 to 500.0 g / cm), and the DC voltage or the AC voltage is applied to the DC voltage. Superposed ones are used. When the AC voltage is superimposed, it is preferable that the AC voltage is 0.5 to 5.0 kVpp, the AC frequency is 50 to 5 kHz, and the absolute value of the DC voltage is 200 to 1500 V. The polarity of the voltage depends on the image forming method used.

  As a waveform of the AC voltage used in the charging process, a sine wave, a rectangular wave, a triangular wave, or the like can be used as appropriate. Further, it may be a pulse wave formed by periodically turning on / off a DC power source. In this way, a bias that periodically changes the voltage value can be used as the waveform of the AC voltage.

  The material of the roller member is not limited to the elastic foam, but as the material of the elastic body, ethylene-propylene-diene polyethylene (EPDM), urethane, butadiene acrylonitrile rubber (NBR), silicone rubber, isoprene rubber, etc. In order to adjust the resistance, a rubber material in which a conductive material such as carbon black or a metal oxide is dispersed, or a foamed material thereof can be used. It is also possible to adjust the resistance using an ion conductive material without dispersing the conductive particles or in combination with the conductive particles.

  Moreover, aluminum, SUS, etc. are mentioned as a metal core used for a roller member. The roller member is disposed in pressure contact with the object to be charged as the image carrier against the elasticity with a predetermined pressing force to form a charging contact portion that is a contact portion between the roller member and the image carrier. Let

  Next, the contact transfer process preferably applied in the image forming method of the present invention will be specifically described.

  The contact transfer process is a process in which the electrostatic latent image carrier is electrostatically transferred to the recording medium while contacting the transfer member through the recording medium. It is preferably 9.9 N / m (3.0 g / cm) or more, more preferably 19.6 N / m (20.0 g / cm) or more. If the linear pressure as the contact pressure is less than 2.9 N / m (3.0 g / cm), the recording medium is likely to be transported and transfer defects are likely to occur.

  The image forming method of the present invention to which the contact transfer method is applied is particularly effective for an image forming apparatus having a small-diameter electrostatic latent image carrier having a diameter of 50 mm or less. That is, in the case of a small-diameter electrostatic latent image carrier, the curvature with respect to the same linear pressure is large, and pressure concentration tends to occur at the contact portion. The belt-like electrostatic latent image carrier is considered to have the same phenomenon, but the present invention is also effective for an image forming apparatus having a radius of curvature of 25 mm or less at the transfer portion.

  In the image forming method of the present invention, in order to obtain a high-quality image, the toner has a layer thickness smaller than the closest distance (between S and D) between the toner carrier and the electrostatic latent image carrier on the toner carrier. It is preferable to apply and to develop in the development step. Generally, the toner layer thickness regulating member (magnetic cut, regulating blade, etc.) that regulates the toner on the toner carrier regulates the toner layer thickness on the toner carrier. Therefore, it is preferable to regulate by contacting the toner carrier. A regulating blade is generally used as the layer pressure regulating member that comes into contact with the toner carrier, and can be suitably used in the present invention.

  By regulating the toner layer thickness by bringing the regulating blade into contact with the image carrier, it is effective to improve transfer efficiency and reduce fog. This is because the material of the regulating blade can be designed according to the chargeability of the toner, and since the regulating blade is in contact with the toner carrier with a specific contact pressure, sufficient frictional charging is performed, This is considered to be because the charge amount is increased and uniform chargeability is obtained. Further, by suppressing fogging and increasing transfer efficiency in this manner, good cleaner-less properties are maintained, image defects such as charging defects do not occur, and high-definition images can be maintained even during long-term use.

  As the regulating blade, a rubber elastic body such as silicone rubber, urethane rubber and NBR, and a synthetic resin elastic body such as polyethylene terephthalate can be used, and even a composite of them can be used. A rubber elastic body is preferable.

  The material of the regulating blade is greatly involved in charging the toner on the toner carrier. Therefore, when an elastic body is used as the regulating blade, an organic substance or an inorganic substance may be added to the elastic body, and it may be melt-mixed or dispersed. Examples of the substance to be added include metal oxides, metal powders, ceramics, carbon allotropes, whiskers, inorganic fibers, dyes, pigments, and surfactants. Further, a charge control substance such as resin, rubber, metal oxide, or metal is applied to the contact portion of the toner carrier for the purpose of controlling the chargeability of the toner against an elastic support such as rubber, synthetic resin, or metal elastic body. You may use what was attached to. Further, it is preferable that the metal elastic body is bonded with resin and rubber so as to contact the toner carrier contact portion.

  When the toner is negatively charged, the material used for the regulating blade is preferably a material that is easily charged to positive polarity such as urethane rubber, urethane resin, polyamide resin, or nylon resin. When the toner is positively charged, the material used for the regulating blade is a material that is easily charged to negative polarity such as urethane rubber, urethane resin, silicone rubber, silicone resin, polyester resin, fluorine resin, polyimide resin. Is preferred.

  When the toner carrier contact part is a molded body of resin or rubber, in order to adjust the chargeability of the toner, it contains metal oxide such as silica, alumina, titania, tin oxide, zirconia oxide, zinc oxide, carbon It is also preferable to include black, a charge control agent generally used for toner.

  It is also important to control the ten-point average roughness Rz of the regulating blade surface. Rz on the surface of the regulating blade is preferably 2.5 μm or more and 10.5 μm or less. When the thickness is less than 2.5 μm, the toner on the toner carrying member becomes difficult to be caught and the triboelectric charge amount is insufficient, so that the image density tends to decrease. On the other hand, if Rz exceeds 10.5 μm, the toner is excessively caught on the regulating blade, and the toner stagnating between the toner carrier and the regulating blade increases, so that development streaks are likely to occur. Rz of the regulating blade is more preferably 3.5 μm or more and 9.5 μm or less.

  The base, which is the upper side of the regulating blade, is fixedly held on the toner container side, and the lower side is bent against the elastic force of the blade in the forward or reverse direction of the toner carrying member on the surface of the toner carrying member. Abut with moderate elastic pressure.

  The contact pressure between the blade and the toner carrier is preferably 4.9 N / m (5.0 g / cm) or more and 118.0 N / m (120 g / cm) or less in the direction of the toner carrier bus. When the contact pressure is less than 4.9 N / m (5.0 g / cm), the amount of charge applied to the toner tends to be insufficient, and the density tends to decrease. When the contact pressure exceeds 118.0 N / m (120.0 g / cm), a large pressure is applied to the toner, so that development streaks are likely to deteriorate.

  It is important that the outer diameter of the toner carrier used in the present invention is 8.0 mm or more and less than 12.0 mm. When the outer diameter of the toner carrier is 12.0 mm or more, the development area is widened and the image density can be easily obtained. However, sufficient compactness cannot be achieved, and the process unit cannot be reduced in size. On the other hand, when the outer diameter of the toner carrier is less than 8.0 mm, the magnetic force of the enclosing magnet roller cannot be sufficiently obtained, and the fog is greatly deteriorated. In addition, the toner coat on the toner carrier becomes unstable and the development area is too narrow, so that the image density is remarkably lowered. Further, since the curvature is further increased, the development streaks are likely to deteriorate.

  The toner carrier used in the present invention is preferably a conductive cylinder (developing roller) formed of a metal or alloy such as aluminum or stainless steel. A conductive cylinder may be formed of a resin composition having sufficient mechanical strength and conductivity, or a conductive rubber roller may be used. Moreover, it is not limited to the cylindrical shape as described above, and may be an endless belt that is rotationally driven.

  The surface roughness of the toner carrier used in the present invention is preferably in the range of 0.80 μm to 1.10 μm in terms of JIS centerline average roughness (Ra). When Ra is 0.80 μm or more and 1.10 μm or less, a sufficient amount of toner can be obtained and the amount of toner on the toner carrier can be easily regulated. When Ra exceeds 1.10 μm, fogging tends to deteriorate due to an excessive toner conveyance amount. When Ra is less than 0.80 μm, the amount of toner transport is insufficient, so that the image density tends to decrease. Furthermore, since the load on the toner particles increases, the level of development streaks tends to deteriorate. Therefore, Ra is preferably 0.80 μm or more and 1.10 μm or less, and Ra of the toner carrier is more preferably 0.85 μm or more and 1.05 μm or less.

  In order to make the surface roughness (Ra) of the toner carrier in the present invention in the above range, for example, the polishing state of the surface layer of the toner carrier is changed, or spherical carbon particles, carbon fine particles, graphite, resin fine particles, etc. are added. This is possible.

  The surface of the toner carrier in the present invention is preferably coated with a resin layer in which conductive fine particles and / or a lubricant are dispersed.

The conductive fine particles contained in the coating layer of the toner carrier preferably have a resistance value of 0.5 Ωcm or less after being pressed at 11.7 Mpa (120 kg / cm ² ). The conductive fine particles are preferably carbon fine particles, a mixture of carbon fine particles and crystalline graphite, or crystalline graphite. The conductive fine particles preferably have a particle size of 0.005 μm or more and 10.000 μm or less.

  Examples of the resin used for the resin layer include thermoplastic resins such as styrene resins, vinyl resins, polyethersulfone resins, polycarbonate resins, polyphenylene oxide resins, polyamide resins, fluorine resins, fiber resins, and acrylic resins. Thermosetting resins or photocurable resins such as epoxy resins, polyester resins, alkyd resins, phenol resins, melamine resins, polyurethane resins, urea resins, silicone resins, and polyimide resins can be used.

  Among them, those having releasability such as silicone resin and fluororesin, and those having excellent mechanical properties such as polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol resin, polyester, polyurethane, styrene resin are more. preferable. In particular, a phenol resin is preferable. The conductive fine particles are preferably used in an amount of 3 to 20 parts by mass per 10 parts by mass of the resin component.

  When carbon fine particles and graphite particles are used in combination, it is preferable to use 1 to 50 parts by mass of carbon fine particles per 10 parts by mass of graphite.

The volume resistivity of the resin layer of the toner carrier in which conductive fine particles are dispersed is preferably from 10 ⁻⁶ Ωcm to 10 ⁶ Ωcm.

  In the present invention, it is preferable that the surface of the toner carrier carrying the toner moves in the same direction as the moving direction of the surface of the image carrier. Further, the moving speed of the toner carrier is preferably 1.00 times or more and 1.30 times or less as a ratio with respect to the moving speed of the image carrier. When the moving speed ratio is 1.00 times or less, it is difficult to obtain a sufficient image density, and the image quality is liable to deteriorate. On the other hand, when the moving speed of the toner carrier is faster than 1.30 times, the toner is likely to be deteriorated, and the image quality is deteriorated by long-term use.

  The image carrier of the present invention preferably has a fixed magnet having multiple poles inside, and preferably has 3 to 10 poles.

  In the present invention, the developing step is a step of forming a toner image by applying an alternating electric field as a developing bias to the toner carrier and transferring the toner to the electrostatic latent image on the electrostatic latent image carrier. Preferably, the applied developing bias may be a voltage obtained by superimposing an alternating electric field on a DC voltage.

  As the waveform of the alternating electric field, a sine wave, a rectangular wave, a triangular wave, or the like can be used as appropriate. Further, it may be a pulse wave formed by periodically turning on / off a DC power source. As described above, a bias whose voltage value periodically changes can be used as the waveform of the alternating electric field.

  In the present invention, it is preferable that an electrostatic latent image forming step for forming an electrostatic latent image on the charging surface of the image carrier is performed by an image exposure unit. The image exposure means for forming the electrostatic latent image is not limited to the laser scanning exposure means for forming a digital latent image, and other light emitting elements such as normal analog image exposure and LEDs may be used. It does not matter as long as it can form an electrostatic latent image corresponding to image information, such as a combination of a light emitting element such as a fluorescent lamp and a liquid crystal shutter.

  Next, a method for measuring each physical property related to the toner of the present invention will be described.

<Weight average particle diameter of toner (D4)>
The toner according to the present invention has a weight average particle diameter (D4) of a precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) equipped with a 100 μm aperture tube. Using the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for measurement condition setting and measurement data analysis, measurement was performed with 25,000 effective measurement channels. The measurement data was analyzed and calculated.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

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

  In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is 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 to 2 μm to 60 μm.

  The specific measurement method is as follows.

  (1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.

  (2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder pH 7 precision measurement is used as a dispersant therein. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion exchange water is added.

  (3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic dispersion device “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W. A fixed amount of ion-exchanged water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.

  (4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.

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

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

  (7) Analyze the measured data using the dedicated software attached to the device, and calculate the weight average particle size (D4. Analytical / volume statistics (arithmetic when graph / volume% is set with the dedicated software) The “average diameter” on the (average) screen is the weight average particle diameter (D4).

<Toner mode circularity>
The mode circularity of the toner was measured with a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during calibration.

  As a specific measurement method, an appropriate amount of a surfactant as a dispersant, preferably sodium dodecylbenzenesulfonate, is added to 20 ml of ion-exchanged water, 0.02 g of a measurement sample is added, an oscillation frequency of 50 kHz, electrical output Dispersion treatment was performed for 2 minutes using a 150 W desktop ultrasonic cleaner / disperser (for example, “VS-150” (manufactured by Velvo Crea)) to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC.

  The flow type particle image analyzer equipped with a standard objective lens (10 ×) was used for the measurement, and a particle sheath “PSE-900A” (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion prepared in accordance with the above procedure is introduced into the flow type particle image analyzer, 3000 toner particles are measured in the total count mode in the HPF measurement mode, and the binarization threshold at the time of particle analysis is 85%. Then, the analysis particle diameter was limited to a circle equivalent diameter of 2.00 μm or more and 200.00 μm or less, and the mode circularity of the toner was determined.

  In measurement, automatic focus adjustment is performed using standard latex particles (for example, “5100A” manufactured by Duke Scientific is diluted with ion-exchanged water) before the measurement is started. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In this embodiment, a flow type particle image analyzer which has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, has an analysis particle diameter of 2.00 μm in equivalent circle diameter. The measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that it was limited to 200.00 μm or less.

  The measurement principle of the flow-type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to capture flowing particles as a still image and perform image analysis. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched between sheath liquids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with strobe light at 1/60 second intervals, and the flowing particles can be photographed as a still image. Further, since the flow is flat, the image is taken in a focused state. The particle image is captured by a CCD camera, and the captured image is subjected to image processing at an image processing resolution of 512 × 512 (0.37 × 0.37 μm per pixel), and the contour of each particle image is extracted, The projected area S, the peripheral length L, and the like are measured.

Next, the equivalent circle diameter and the circularity are obtained using the area S and the peripheral length L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the circumference of the circle obtained from the equivalent circle diameter by the circumference of the projected particle image. And is calculated by the following formula.
Circularity C = 2 × (π × S) 1/2 / L

  When the particle image is circular, the degree of circularity is 1, and the degree of unevenness on the outer periphery of the particle image increases, and the degree of circularity decreases. After calculating the circularity of each particle, the range of the circularity of 0.200 to 1.000 is divided into 800, and in the obtained circularity frequency distribution circularity distribution, the most frequent circularity value is referred to as mode circularity. did.

<Measurement of the amount of carbon atoms and oxygen atoms on the toner surface by ESCA (X-ray photoelectron spectroscopy)>
The element concentration on the toner surface is measured using Quantum 2000 manufactured by ULVAC-PHI, under the following conditions.
Sample measurement range: Φ100μm
Photoelectron capture angle: 45 °
X-ray: 50μ12.5W15kV
PassEnergy: 46.95 eV
Step Size: 0.200eV
No of Sweeps: 1-20
Setting measurement time: 30 min

  In the present invention, for example, Quantum 2000 (ULVAC-PHI) is used for ESCA measurement. As a measurement principle, photoelectrons are generated by using an X-ray source, and energy based on an intrinsic scientific combination of substances is measured. As the X-ray, monochromatic Al—Kα is used, and measurement is performed under the conditions of a beam diameter of 50 μm and a pass energy of 46.95 eV. Thus, the ratio of the peak area of carbon atoms and oxygen atoms to the total peak area obtained is calculated.

<Micro compression test method>
For the micro compression test in the present invention, an ultra micro hardness tester ENT1100 manufactured by Elionix Co., Ltd. was used. This device obtains the load load-indentation depth curve by continuously measuring the load and indentation depth on the indenter during loading and unloading when the indenter is pushed into the sample. From this, data such as micro compression hardness and elastic modulus are obtained. The measuring method using the apparatus is described in the ENT1100 operation manual issued by Elionix, Inc., and is specifically as follows.

The working indenter is a 20 μm × 20 μm square flat indenter, and the measurement environment is a temperature of 27 ° C. and a humidity of 60% RH. The maximum load is set to 9.8 × 10 ⁻⁴ N and the load is applied at a speed of 9.8 × 10 ⁻⁵ N / sec. After reaching the maximum load (9.8 × 10 ⁻⁴ N), leave it at that load for 0.1 sec. The amount of displacement at the elapse of 0.1 sec after reaching the maximum load is defined as the maximum displacement amount (μm). Subsequently, the load is unloaded at a speed of 9.8 × 10 ⁻⁵ N / sec from the maximum load, and the measurement is terminated when the load becomes zero.

  In actual measurement, a toner is applied on a ceramic cell, and air is blown so that the toner is dispersed on the cell. The cell is set in the apparatus and measured.

  For the measurement, while looking through the microscope attached to the apparatus, a toner having one particle on the measurement screen (horizontal width: 160 μm, vertical width: 120 μm) is selected. In order to eliminate the displacement error as much as possible, a toner having a weight average diameter D4 ± 0.20 μm is selected and measured. An arbitrary toner is selected from the measurement screen. The particle diameter measuring means measures the major axis and minor axis of the toner using software attached to the microhardness meter ENT1100, and the aspect ratio [( (Major axis + minor axis) / 2] was defined as the particle diameter.

  At the time of measurement, 120 arbitrary toners whose particle diameter satisfies the above conditions are selected and the maximum displacement is measured. In order to eliminate measurement errors and fluctuations, data is selected as follows. Of the obtained maximum displacement values, 10 pieces of data are removed in order from the largest to the smallest. Then, using the maximum value and the minimum value among the remaining 100 data, the difference between the maximum value and the minimum value of the present invention is obtained.

<Measurement of melting point of wax and glass transition point of binder resin>
The melting point of the wax is measured according to ASTM D3418-99 using a differential scanning calorimeter “Q1000” (manufactured by TA Instruments). The temperature correction of the device detection unit uses the melting points of indium and zinc.

  Specifically, about 5 mg of wax is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference, and the temperature is raised between a measurement temperature range of 30 ° C. and 200 ° C. Measurement is performed at a rate of 10 ° C./min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again. The temperature of the maximum endothermic peak of the DSC curve in the temperature range of 30 ° C. or more and 200 ° C. or less in the second temperature raising process is defined as the melting point of the wax of the present invention.

  Further, the glass transition point of the binder resin is also measured using the same measuring device as the wax melting point.

  Specifically, about 5 mg of binder resin is precisely weighed, put in an aluminum pan, and an empty aluminum pan is used as a reference, and the temperature rising rate is between 30 ° C. and 200 ° C. Measurement is performed at 10 ° C./min. In this temperature raising process, a specific heat change is obtained in the temperature range of 40 ° C. or more and 100 ° C. or less. At this time, the intersection between the line of the midpoint of the baseline before and after the change in specific heat and the differential heat curve is defined as the glass transition point of the binder resin.

<Measuring method of ten-point average roughness Rz of toner layer thickness regulating member surface>
Rz of the toner layer thickness regulating member (hereinafter, regulating blade) is measured as follows.

1) Preparation of sample Cut the regulating blade into a size of about 1 cm square. However, as long as there is a sufficient area for irradiating the laser in the observation with a laser microscope, the size to be cut is not particularly limited.

2) Measurement conditions Set parameters for measurement as follows.
Objective lens magnification: 20 × Optical zoom magnification: 1 × Digital zoom magnification: 1 × RUN MODE: Color super depth LASER (gain): 594
LASER (offset): -1328
Camera settings (shutter): 158
Camera setting (white balance): 3200k
Camera setting (gain): 0

3) Setting of sample Set the cut regulating blade on the stage of the laser microscope so that the portion that contacts the toner carrier becomes the observation surface.

4) Measurement The surface of the regulating blade is measured with a measurement PITCH of 0.1 μm.

5) Image processing In order to correct the overall distortion and inclination of the image obtained by the measurement, the following processing was performed.

[1. Tilt correction]
Correction method: Surface correction (automatic)
Process target: Height The following process was performed in order to remove fine noise components in the image obtained by the measurement.

[2. Filter processing]
Process target: Smoothing (height data)
Size: 7 x 7
Number of executions: 1
File Type: Median

[3. Filter processing]
Process target: Smoothing (height data)
Size: 3 x 3
Number of executions: 1
File type: Simple average

6) Analysis Height data is used for analysis. A scale is drawn on the obtained height data image, a range of 200 μm × 260 μm is selected, and a ten-point average roughness Rz in this range is taken as a measurement result.

<Measurement of arithmetic average roughness Ra of toner carrier surface>
The arithmetic average roughness (Ra) of the toner carrier surface is measured using a surf coder SE-3500 manufactured by Kosaka Laboratory, based on the surface roughness of JIS B0601. Measurement conditions were 9 points (3 points in the circumferential direction for each of 3 points equally spaced in the axial direction) at a cutoff of 0.8 mm, an evaluation length of 4 mm, and a feed rate of 0.5 mm / s. And the average value was taken.

<Measurement of softening point of binder resin>
The softening point of the binder resin was measured with a flow tester CFT-500D type (manufactured by Shimadzu Corporation). About 1.0 g of toner having a 60-mesh (mesh size of 250 μm) pass is weighed as a sample, and this is pressed using a molding machine with a load of 100 kg / cm ² (9800 kPa) for 1 minute. A load of 10 kgf (98 N) was applied to this sample, and the plunger drop amount of the flow tester was measured by a temperature rising method with a temperature rising temperature of 4.0 ° C./min, a die diameter of 1.0 mm, and a die length of 1.0 mm. The temperature at which half of the sample flows out is defined as the softening point.

<Measurement of saturation and residual magnetization of magnetic material>
In the present invention, the strength of saturation magnetization and remanent magnetization of the magnetic material is determined by using an oscillating magnetometer VSM P-1-10 (manufactured by Toei Kogyo Co., Ltd.) and an external magnetic field of 79.6 kA / m at room temperature of 25 ° C. Measure with

  Hereinafter, the present invention will be described more specifically with reference to production examples and examples, but these do not limit the present invention in any way. In addition, all the parts in the following mixing | blending show a mass part.

<Manufacture of magnetic material>
In ferrous sulfate aqueous solution, l. An aqueous solution containing ferrous hydroxide was prepared by mixing 0 to 1.1 equivalents of caustic soda solution and iron element with an amount of SiO ₂ of 1.20% by mass in terms of silicon element with respect to iron element. . The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.

Next, after adding ferrous sulfate aqueous solution to this slurry liquid to 0.9 to 1.2 equivalents relative to the initial alkali amount (sodium component of caustic soda), the slurry liquid was maintained at pH 8.5, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. This slurry was filtered, washed, dried and pulverized to have a volume average particle size of 0.22 μm, a magnetization intensity of 66.1 Am ² / kg at a magnetic field of 79.6 kA / m (1000 oersted), and a residual magnetization of 6 A magnetic material of 0.0 Am ² / kg was obtained.

<Manufacture of binder resins 1 to 4>
The monomers of the condensation polymerization resin other than trimellitic acid, both reactive compounds and the esterification catalyst shown in Table 1 were subjected to condensation polymerization at 230 ° C. for 6 hours in a nitrogen atmosphere, and then cooled to 160 ° C. After adding 175 g of trimellitic acid to the reaction vessel, a mixture of the addition polymerization resin monomer and the polymerization initiator shown in Table 1 was added dropwise over 2 hours with stirring at 160 ° C. Furthermore, after maintaining the same temperature for 1 hour and performing addition polymerization reaction, it heated up at 200 degreeC and performed polycondensation reaction. Resins 1 to 4 were obtained by reacting until the softening point reached the desired temperature.

<Manufacture of binder resin 5>
A monomer other than trimellitic acid and the esterification catalyst shown in Table 1 were put into a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. After reacting until the reaction rate reached 90%, the reaction temperature was lowered to 180 ° C. and adipic acid was added. After raising the temperature to 210 ° C. at a rate of 10 ° C./h and reacting until the reaction rate reaches 90%, trimellitic anhydride was added and reacted at 210 ° C. for 1 hour at normal pressure, then the desired The binder resin 5 was obtained by reacting until the softening point was reached.

<Manufacture of toner 1>
Binder resin 1 100 parts Magnetic material 95 parts Polyethylene wax (melting point 115 ° C.) 5 parts Iron complex of monoazo dye (T-77 Hodogaya Chemical Co., Ltd.) 2 parts The above mixture is premixed with a Henschel mixer and then heated to 120 ° C. The resulting biaxial extruder was melt-kneaded, and the cooled kneaded product was coarsely pulverized with a hammer mill to obtain a coarsely pulverized toner product. The obtained coarsely pulverized product is mechanically pulverized using a mechanical pulverizer turbo mill (manufactured by Turbo Kogyo Co., Ltd.) and finely pulverized. The fine powder and coarse powder were simultaneously classified and removed by an elbow jet classifier manufactured by Sangyo Co., Ltd. The raw material toner particles thus obtained had a weight average particle diameter (D4) measured by a Coulter counter method of 6.3 μm.

  The obtained toner particles were subjected to surface modification by Meteorbomb MR-3 type (manufactured by Nippon Pneumatic Industry Co., Ltd.), which is a device for modifying the surface of the toner particles by blowing hot air. The conditions for the surface modification were as follows: raw material supply rate 2 kg / hr, hot air flow rate 700 L / min, discharge hot air temperature 300 ° C., and the weight-average particle diameter (D4) of the surface-modified toner particles obtained was 6.8 μm. Met.

  Toner 1 was prepared by mixing 100 parts of surface-modified toner particles and 1.35 parts of hydrophobic silica fine powder treated with hexamethyldisilazane and then treated with dimethylsilicone oil using a Henschel mixer. Table 2 shows the physical properties and formulation of Toner 1.

<Manufacture of toner 2>
Toner 1 was obtained in the same manner as in the production of toner 1 except that polyethylene wax was changed to paraffin wax having a melting point of 78 ° C. in the production of toner 1. Table 2 shows the physical properties and formulation of Toner 2.

<Manufacture of toner 3>
Toner 1 was obtained in the same manner as in the production of toner 1 except that polyethylene wax was changed to polypropylene wax having a melting point of 152 ° C. in the production of toner 1. Table 2 shows the physical properties and formulation of Toner 3.

<Manufacture of toner 4>
Toner 4 was obtained in the same manner as in the production of toner 1 except that polyethylene wax was changed to behenyl behenate having a melting point of 72 ° C. in the production of toner 1. Table 2 shows the physical properties of Toner 4.

<Manufacture of toner 5>
In the production of the toner 4, except that the binder resin 1 is changed to the binder resin 2, and the surface modification conditions are changed to a raw material supply rate of 3.0 kg / hr, a hot air flow rate of 900 L / min, and a discharge hot air temperature of 200 ° C. Was similar to the production of toner 4 to give toner 5. Table 2 shows the physical properties and formulation of Toner 5.

<Manufacture of toner 6>
In the production of the toner 4, except that the binder resin 1 is changed to the binder resin 3, and the conditions for surface modification are changed to a raw material supply rate of 1.2 kg / hr, a hot air flow rate of 500 L / min, and a discharge hot air temperature of 400 ° C. Was similar to the production of Toner 4 to obtain Toner 6. Table 2 shows the physical properties and formulation of Toner 6.

<Manufacture of toner 7>
A toner 7 was obtained in the same manner as in the production of the toner 5 except that behenyl behenate was changed to a polypropylene wax having a melting point of 152 ° C. in the production of the toner 5. Table 2 shows the physical properties and formulation of Toner 7.

<Manufacture of Comparative Toner 1>
Binder resin 5 100 parts Magnetic material 95 parts Behenyl behenate (melting point 72 ° C) 10 parts Iron complex of monoazo dye (T-77 manufactured by Hodogaya Chemical Co., Ltd.) 2 parts The above mixture was premixed with a Henschel mixer and then heated to 120 ° C. The mixture was melt kneaded with a heated biaxial extruder, and the cooled kneaded product was coarsely pulverized with a hammer mill to obtain a coarsely pulverized toner product. The resulting coarsely pulverized product is mechanically pulverized and finely pulverized using a mechanical pulverizer turbo mill (made by Turbo Kogyo Co., Ltd., coated on the rotor and stator surfaces with chromium alloy plating containing chromium carbide). Then, the finely pulverized product was classified and removed at the same time by a multi-division classifier (Elbow Jet Classifier manufactured by Nittetsu Mining Co., Ltd.) using the Coanda effect. The raw material toner particles thus obtained had a weight average particle diameter (D4) measured by a Coulter counter method of 6.3 μm.

  The obtained toner particles were subjected to surface modification with Meteorenbo MR-3 type (manufactured by Nippon Pneumatic Kogyo Co., Ltd.) which is a device for modifying the surface of the toner particles by blowing hot air on the raw toner particles. . The conditions for surface modification were as follows: raw material supply rate 0.2 kg / hr, hot air flow rate 400 L / min, discharge hot air temperature 450 ° C., and the weight average particle diameter (D4) of the surface modified toner particles obtained was 7. 0.0 μm.

  100 parts of the surface-modified toner particles and 1.35 parts of hydrophobic silica fine powder treated with hexamethyldisilazane and then treated with dimethylsilicone oil are mixed with a Henschel mixer to prepare a comparative toner 1. did. Table 2 shows the physical properties and formulation of the comparative toner 1.

<Production of Comparative Toner 2>
In the production example of Comparative Toner 1, behenyl behenate was changed to polypropylene wax having a melting point of 152 ° C., and the conditions for surface modification were as follows: raw material supply rate 4.0 kg / hr, hot air flow rate 1000 L / min, discharged hot air temperature 195 ° C. A comparative toner 2 was obtained in the same manner as in the production of the comparative toner 1 except for the change. Table 2 shows the physical properties and formulation of the comparative toner 2.

<Manufacture of toner carrier 1>
A toner carrier having a resin coating layer on the substrate surface was prepared as follows.
Resol type phenol resin (J325: manufactured by Dainippon Ink & Chemicals, Inc.) 250 parts conductive carbon black 10 parts (produced by Columbia Carbon Co., Ltd., trade name: Conductex 975)
Graphite particles (particle size: 2.0 μm) 90 parts Compound 1 30 parts Conductive spherical particles (Nikabeads ICB0520 made by Nippon Carbon Co., Ltd.) 30 parts Ethanol 200 parts Compound 1 is represented by the following structural formula.

  Glass beads having a diameter of 1 mm were added as media particles to the above material, dispersed for 2 hours in a sand mill, the beads were separated using a sieve, and the solid content was adjusted to 38% with ethanol to obtain a coating solution. Using this coating solution, vertically stand on a ground aluminum cylindrical tube with an outer diameter of 10 mmφ and a center line average roughness Ra = 0.2 μm, rotate at a constant speed, and mask the upper and lower ends. The resin coating layer was formed by coating while lowering the spray gun at a constant speed. The coating was performed in an environment of 23 ° C./50% RH. Subsequently, the resin coating layer was cured by heating at 150 ° C. for 30 minutes in a hot air drying furnace, and the toner carrier 1 was produced. Table 3 shows the physical properties of the toner carrier 1.

<Manufacture of toner carrier 2>
In the production of the toner carrier 1, a toner carrier 2 was obtained in the same manner as in the production of the toner carrier 1 except that 30 parts of the conductive spherical particles were changed to 20 parts. Table 3 shows the physical properties of the toner carrier 2.

<Manufacture of toner carrier 3>
In the production of the toner carrier 1, a toner carrier 3 was obtained in the same manner as in the production of the toner carrier 1 except that 30 parts of the conductive spherical particles were changed to 40 parts. Table 3 shows the physical properties of the toner carrier 3.

<Manufacture of toner carrier 4>
In the production of the toner carrier 1, a toner carrier 4 was obtained in the same manner as in the production of the toner carrier 1 except that 30 parts of the conductive spherical particles were changed to 15 parts. Table 3 shows the physical properties of the toner carrier 4.

<Manufacture of toner carrier 5>
In the production of the toner carrier 1, a toner carrier 5 was obtained in the same manner as in the production of the toner carrier 1 except that 30 parts of the conductive spherical particles were changed to 45 parts. Table 3 shows the physical properties of the toner carrier 5.

<Manufacture of toner carrier 6>
A toner carrier 6 was obtained in the same manner as the toner carrier 1 except that the aluminum cylinder having an outer diameter of 10 mmφ was changed to an aluminum cylinder having an outer diameter of 7.5 mmφ in the production of the toner carrier 1. Table 3 shows the physical properties of the toner carrier 6.

<Manufacture of toner layer thickness regulating member 1>
While the centrifugal mold heated to 140 ° C. is rotated at a rotation speed of 800 rpm, a thermosetting resin liquid (epoxy resin heat-resistant temperature 150 ° C.) is poured into the centrifugal mold and sufficiently cured by heating. Thus, a holding layer (eccentricity compensation layer) having a thickness of 0.5 mm was provided. Next, in the process of forming a release layer of silicone rubber to a thickness of 1.0 mm on the inner peripheral surface of the holding layer, the inner peripheral surface is in toluene before the release layer is completely cured. The surface-roughening agent (graphite fluoride weight average particle size 8.0 μm, standard deviation 1.53) dispersed in was sprayed. A urethane forming liquid was poured into the release layer thus formed to obtain a toner layer thickness regulating member 1. Table 4 shows Rz of the toner layer thickness regulating member 1.

<Manufacture of toner layer thickness regulating members 2 to 5>
In the toner layer thickness regulating member manufacturing method, the toner layer thickness regulating members 2 to 5 were prepared by changing the particle size or the amount of the surface roughening agent contained in the release layer. Table 4 shows Rz of the toner layer thickness regulating members 2 to 5.

<Example 1>
An LBP3000 (manufactured by Canon) was used as the image forming apparatus, and the cartridge was modified so that the toner carrier 1 and the toner layer thickness regulating member 1 could be inserted.

Toner 1, toner carrier 1 and toner layer thickness regulating member 1 were used, the free length of the toner regulating blade was adjusted to 0.7 mm, and the contact pressure with the toner carrier was adjusted to 20N. Using the cartridge thus modified, it was used under normal temperature and humidity conditions (23 ° C / 60% RH, indicated as “N / N” in the table) and under high temperature and high humidity conditions (32.5 ° C / 80% RH, table). Middle “H / H”), 5000 horizontal lines with a printing rate of 2% were output in a 7-second intermittent mode. As the recording medium, letter size paper of 75 g / m ² was used. As a result, there was no development streak after the durability test, and a high-density image could be obtained. The evaluation results are shown in Table 5.

  The evaluation methods for each evaluation performed in the examples and comparative examples of the present invention and the judgment criteria thereof will be described below.

(Image density)
For the image density, a solid image portion was output before and after 5000 images were printed, and the density of the solid image was measured with a Macbeth reflection densitometer (manufactured by Macbeth).

(Fog)
A white image was output after the image was printed on 5000 sheets, and the reflectance was measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. On the other hand, the reflectance of the transfer paper (standard paper) before white image formation was measured in the same manner. The filter used was a green filter, and fog was calculated according to the following formula.
Fog (reflectance) (%) = reflectance of standard paper (%)-reflectance of white image sample (%)

The fog was evaluated according to the following criteria using the maximum fog value obtained.
A: Very good (less than 1.0%)
B: Good (1.0% or more and less than 2.0%)
C: Practical level (2.0% or more and less than 3.0%)
D: Practically unfavorable level (3.0% or more)

(Development stripe)
After the endurance, 10 line images of 2 dots and 3 spaces were output at a resolution of 600 dpi, and the state of development streaks was visually confirmed. The worst developed streak product in the image was evaluated according to the following criteria as a result of the sample.
A: No streaking B: There are minor streaks, but there is no problem in practical use.
C: Although there is one strong streak, it is a practical level.
D: There are two or three strong streaks, but at a practical level.
E: There are 3 or more strong streaks, which is an undesirable level for practical use.

<Examples 2 to 5>
An image output test was performed in the same manner as in Example 1 except that the toner carriers 2, 3, 4, and 5 were used. As a result, an image having no practical problem before and after the durability test was obtained with any toner. The evaluation results are shown in Table 5.

<Examples 6 to 9>
An image printing test was performed in the same manner as in Example 5 except that the toner layer thickness regulating members 2, 3, 4, and 5 were used. As a result, an image having no practical problem before and after the durability test was obtained with any toner. The evaluation results are shown in Table 5.

<Comparative Example 1>
An image formation test was conducted in the same manner as in Example 1 except that the toner carrier 6 was used. As a result, the image density and the development streak were unpreferable levels for practical use. The evaluation results are shown in Table 5.

<Examples 10 to 15>
Using toners 2 to 7, an image output test was performed in the same manner as in Example 1. As a result, an image having no practical problem before and after the durability test was obtained with any toner. The evaluation results are shown in Table 6. Table 6 also shows the results of Example 1 for comparison.

<Comparative Examples 2 and 3>
Using the comparative toners 1 and 2, an image output test was conducted in the same manner as in Example 1. As a result, the image density was low and the development streak level was poor. The evaluation results are shown in Table 6.

FIG. 2 is a schematic cross-sectional view illustrating an example of an image forming apparatus that can suitably use the toner of the present invention.

Explanation of symbols

100 Electrostatic latent image carrier (photoconductor)
102 Toner carrier 114 Transfer member (transfer roller)
116 Cleaner 117 Contact charging member (charging roller)
121 Laser generator (latent image forming means, exposure device)
123 Laser 124 Register roller 125 Conveying belt 126 Fixing device 140 Developer 141 Stirring member

Claims (7)

8. a charging step of applying a voltage to the charging member to charge the image carrier, an electrostatic latent image forming step of writing image information as an electrostatic latent image on the charged image carrier, and an outer diameter for carrying toner. A toner layer thickness regulating member is brought into contact with a toner carrier of 0 mm or more and less than 12.0 mm, a toner layer is formed on the toner carrier, and the image carrier and the toner carrier are spaced apart from each other. Forming a developing portion by disposing, and transferring the toner image to the electrostatic latent image to form a toner image in the developing portion to which an alternating electric field is applied; and transferring the toner image to a recording medium A toner used for an image forming method in which image formation is repeatedly performed on an image carrier,
The toner contains at least a binder resin, a magnetic material, and a wax;
The mode circularity measured by the flow type particle image measuring device of the toner is 0.975 or more,
The peak area of carbon atoms is 88.0% or more and 95.0% or less with respect to the total peak area measured by ESCA (X-ray photoelectron spectroscopy) of the toner, and the peak area of oxygen atoms is 5.0. % To 12.0%,
In the micro-compression test for the toner, the maximum value of the maximum displacement obtained when 100 particles of toner are selected and a load of 9.8 × 10 ⁻⁴ N / sec is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec. A toner having a minimum difference of 1.5 μm or less.   The toner according to claim 1, wherein the binder resin is mainly composed of a hybrid resin having a polyester unit and a vinyl copolymer unit.   The toner according to claim 1, wherein the wax has a melting point of 80 ° C. or more and 150 ° C. or less, and an aliphatic hydrocarbon wax is a main component.   The toner according to claim 2, wherein the polyester unit is a polyester unit condensed with at least a fatty acid tin salt as a catalyst. 8. a charging step of applying a voltage to the charging member to charge the image carrier, an electrostatic latent image forming step of writing image information as an electrostatic latent image on the charged image carrier, and an outer diameter for carrying toner. A toner layer thickness regulating member is brought into contact with a toner carrier of 0 mm or more and less than 12.0 mm, a toner layer is formed on the toner carrier, and the image carrier and the toner carrier are spaced apart from each other. Forming a developing portion by disposing, and transferring the toner image to the electrostatic latent image to form a toner image in the developing portion to which an alternating electric field is applied; and transferring the toner image to a recording medium An image forming method in which image formation is repeatedly performed on an image carrier,
The toner contains at least a binder resin, a magnetic material, and a wax;
The mode circularity measured by the flow type particle image measuring device of the toner is 0.975 or more,
The peak area of carbon atoms is 88.0% or more and 95.0% or less with respect to the total peak area measured by ESCA (X-ray photoelectron spectroscopy) of the toner, and the peak area of oxygen atoms is 5.0. % To 12.0%,
In the micro-compression test for the toner, the maximum value of the maximum displacement obtained when 100 particles of toner are selected and a load of 9.8 × 10 ⁻⁴ N / sec is applied at a load speed of 9.8 × 10 ⁻⁵ N / sec. An image forming method, wherein the difference between the minimum values is 1.5 μm or less.   The layer thickness regulating member is a regulating blade, and the ten-point average roughness Rz measured by a laser microscope on the surface of the portion where the regulating blade contacts the toner carrier is 2.5 μm or more and 10.5 μm or less. The image forming method according to claim 5.   7. The image forming method according to claim 5, wherein the toner carrying member has a surface roughness Ra of 0.80 μm or more and 1.10 μm or less.

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