JP2009122522A - Electrostatic charge image developing toner, electrostatic charge image developer, cartridge for electrostatic charge image developer, image forming apparatus, process cartridge, fixing method and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner which, even in the formation of an image with a small end margin of a recording medium, ensures good image detachability from a fixing member, forms a highly glossy image, and has good offset resistance, an electrostatic charge image developer, a cartridge for an electrostatic charge image developer, an image forming apparatus, a process cartridge, a fixing method and an image forming method. <P>SOLUTION: The electrostatic charge image developing toner includes at least a crystalline polyester resin, an amorphous polyester resin, aluminum element, tin element and a release agent, wherein the content of the aluminum element is 0.005-0.060 mass% based on the entire toner, the content of the tin element is 0.12-0.72 mass% based on the entire toner, and the release agent has an acid number of 0-5.0 mgKOH/g. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge developing developer, an electrostatic charge image developing developer cartridge, an image forming apparatus, a process cartridge, a fixing method, and an image forming method.

  A method of visualizing an image through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic latent image is formed on a photoreceptor by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and visualized through a transfer and fixing process.

  The developer used here includes a two-component developer composed of a toner and a carrier, and a one-component developer using a magnetic toner or a non-magnetic toner alone. A kneading and pulverizing method is used in which melt-kneading is performed together with a release agent such as a control agent and wax, and after cooling, pulverized and further classified. In these toners, if necessary, inorganic or organic fine particles for improving fluidity and cleaning properties may be added to the surface of the toner particles.

  On the other hand, in recent years, the image forming method by electrophotography using the toner and developing technology as described above has started to be applied to a part of the printing area due to the progress of digitization and colorization, and graphic arts such as on-demand printing. Practical application in the market is beginning to become remarkable. In addition, the graphic arts market refers to the overall print production-related business market, such as prints that are printed with a small number of copies, original copying such as handwriting and painting, copying, and mass production called re-production. In other words, it is defined as a market that targets industries and sectors related to the production of printed materials, and high image quality to replace printing is required.

  In the graphic arts market, when output on glossy paper typified by coated paper or art paper, if the gloss of the image is lower than the gloss of the paper, the image will be sunk and the image quality and texture will be impaired. Therefore, it is necessary to form a high gloss image.

  On the other hand, with the recent increase in environmental awareness, there is a strong demand for energy saving, and power consumption during fixing is required to be as low as possible. Therefore, it is necessary to obtain good fixing performance even when the fixing temperature is low. In order to reduce the size and weight of printers and copiers, the components are as simple as possible. To obtain high-quality prints with excellent low-temperature fixability without using complex structures. Further improvement of toner performance is indispensable.

  As a general method for fixing a toner latent image on a transfer medium such as paper, there is a thermocompression bonding method. In this method, the toner image is fixed by allowing the toner image on the transfer medium to pass through the surface of the fixing member formed of a material having releasability with respect to the toner while being brought into contact under pressure. is there. In the case of this thermocompression bonding method, the surface of the fixing member and the toner image on the transfer medium are brought into contact with each other under pressure, so that the thermal efficiency is very good and fixing can be performed quickly.

In such a thermocompression bonding method, not only low-temperature fixability is realized, but also a toner that suppresses the high-temperature offset phenomenon and the low-temperature offset phenomenon when the fixing member and the toner image are in pressure contact in the heat-melted state. It is desired to get. Here, the high temperature offset phenomenon means that the toner viscosity decreases due to the fixing temperature being too high, a part of the toner image adheres and / or transfers to the surface of the fixing member, and retransfers to the next transfer target, This is a phenomenon that soils the transfer target. The low temperature offset phenomenon is a phenomenon in which the toner is not fixed on the transfer medium because the toner is not sufficiently melted due to the fixing temperature being too low.
In addition, it is also desired to fix without applying a release agent such as oil on the surface of the fixing member, and a sufficient release property is required for the toner itself.

The purpose of low-temperature fixing can be achieved, for example, by lowering the minimum softening temperature by lowering the softening temperature of the toner by lowering the molecular weight or glass transition temperature of the binder resin. It has also been reported that low-temperature fixability is achieved by using a crystalline polyester resin.
For improving the offset resistance, for example, a method of increasing the elasticity of the binder resin by increasing the molecular weight distribution of the binder resin is conceivable.

Attempts have been made to achieve both low-temperature fixability and offset resistance by focusing on the rheological properties of the toner and controlling the viscoelastic behavior.
For example, Japanese Patent Laid-Open No. 4-353866 (Patent Document 1) has a storage elastic modulus fall start temperature in the range of 100 to 110 ° C., has a specific storage elastic modulus at 150 ° C., and has a loss elastic modulus. An electrophotographic toner having rheological properties having a peak of 125 ° C. or higher is disclosed.
Japanese Patent Laid-Open No. 9-6051 (Patent Document 2) discloses a toner for electrostatic charge development in which the storage elastic modulus of a binder resin is within a specific range at 120 ° C. and the complex elastic modulus is within a specific range at 100 ° C. Is disclosed.
Further, in Japanese Patent Laid-Open No. 2001-305794 (Patent Document 3), fine particles are internally added, the toner has a predetermined complex elastic modulus absolute value G *, a predetermined complex elastic modulus ΔG * (10%) and A toner having ΔG * (100%) is disclosed.

In addition to controlling the viscoelastic behavior of the binder resin, attempts have been made to control the viscoelastic behavior by adding additives such as fine particles into the binder resin.
For example, JP-A-8-220800 (Patent Document 4), JP-A-2001-201886 (Patent Document 5), JP-A-2001-305794 (Patent Document 6), JP-A-2002-082473 (Patent Document). Document 7) discloses a technique for adding inorganic fine particles to a color toner to make the viscoelasticity of the color toner uniform.

  Japanese Patent Laid-Open No. 2001-305781 (Patent Document 8) discloses an internally added fine particle (A) having a contact angle smaller than 90 degrees with the binder resin and an externally added inorganic material having a contact angle larger than 90 degrees with the binder resin. A technology is disclosed that achieves a long life, good transferability, low-temperature fixing, and good releasability with a toner in which fine particles satisfy a predetermined primary particle size relationship.

In Japanese Patent Laid-Open No. 2002-082473 (Patent Document 9), a toner containing inorganic fine particles A having a central particle diameter in the range of 5 to 20 nm and inorganic fine particles B having a central particle diameter in the range of 30 to 100 nm is used. A technique for improving peelability, hot offset resistance, bending resistance, surface glossiness, and fixing characteristics is disclosed.
JP-A-4-353866 Japanese Patent Laid-Open No. 9-6051 JP 2001-305794 A JP-A-8-220800 JP 2001-201886 A JP 2001-305794 A JP 2002-082473 A JP 2001-305781 A JP 2002-082473 A

  An object of the present invention is to provide an electrostatic charge image that has good image peelability from a fixing member even in the formation of an image with a small margin at the tip of a recording medium, forms a highly glossy image, and has good offset resistance. The present invention provides a developing toner, an electrostatic charge developing developer, an electrostatic charge image developing developer cartridge, an image forming apparatus, a process cartridge, a fixing method, and an image forming method.

The above-mentioned subject is achieved by the following present invention.
That is, the invention according to claim 1
Contains a crystalline polyester resin, an amorphous polyester resin, an aluminum element, a tin element, and a release agent,
The content of the aluminum element is 0.005% by mass or more and 0.060% by mass or less based on the whole toner,
The content of the tin element is 0.12% by mass or more and 0.72% by mass or less based on the whole toner,
The toner for developing an electrostatic charge image has an acid value of 0 mgKOH / g or more and 5.0 mgKOH / g or less.

The invention according to claim 2
2. The electrostatic image developing toner according to claim 1, further comprising silicon oxide particles, wherein a dispersion ratio of the silicon oxide particles is 80% or more and 100% or less.

The invention according to claim 3
3. The electrostatic image developing toner according to claim 1, wherein the addition amount of the silicon oxide particles is 1% by mass or more and 10% by mass or less based on the whole toner.

The invention according to claim 4
An electrostatic charge image developing developer comprising at least the electrostatic charge image developing toner according to claim 1.

The invention according to claim 5
Contains a developer that is detached from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus;
The developer is an electrostatic charge image developing developer cartridge which is the electrostatic charge image developing developer according to claim 4.

The invention according to claim 6
An electrostatic latent image carrier;
Charging means for charging the surface of the electrostatic latent image holding member;
Electrostatic latent image forming means for forming an electrostatic latent image on the surface of the electrostatic latent image holding member;
Developing means for developing the electrostatic latent image into a toner image with a developer;
Transfer means for transferring the toner image formed on the surface of the electrostatic latent image holding member to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the recording medium,
The image forming apparatus according to claim 4, wherein the developer is an electrostatic charge image developing developer.

The invention according to claim 7 provides:
The fixing unit includes a first fixing member and a second fixing member in contact with the first fixing member,
The image forming apparatus according to claim 6, wherein a contact width at a contact portion between the first fixing member and the second fixing member is 6 mm or more and 7 mm or less.

The invention according to claim 8 provides:
Development for developing the electrostatic latent image developing developer according to claim 4 and developing the electrostatic latent image formed on the surface of the electrostatic latent image holding body into a toner image by the electrostatic charge image developing developer. Means,
At least one selected from the group consisting of an electrostatic latent image holding body, a charging means for charging the electrostatic latent image holding body, and a toner removing means for removing toner remaining on the surface of the electrostatic latent image holding body And comprising
A process cartridge is detachable from an image forming apparatus.

The invention according to claim 9 is:
A recording medium holding a toner image formed with the electrostatic image developing toner according to claim 1 is in contact with a first fixing member and a second fixing member. In the fixing method, the toner image is fixed on the recording medium by passing it through the contact portion of the fixing member while heating.

The invention according to claim 10 is:
The fixing method according to claim 9, wherein a contact width at the contact portion is 6 mm or greater and 7 mm or less.

The invention according to claim 11 is:
11. The fixing method according to claim 9, wherein a passing time for passing the recording medium holding the toner image while heating at the contact portion is 15 ms or more and 30 ms or less.

The invention according to claim 12
An electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image holding member;
A developing step of developing the electrostatic latent image into a toner image with a developer;
A transfer step of transferring the toner image to the surface of the recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium to the surface of the recording medium;
Including
5. The image forming method according to claim 4, wherein the developer is an electrostatic charge developing developer.

The invention according to claim 13 is:
13. The image forming method according to claim 12, wherein the fixing step is a step of fixing the toner image on the recording medium by the fixing method according to any one of claims 9 to 11.

  According to the first aspect of the invention, even in the formation of an image with a small margin at the tip of the recording medium, the image peelability from the fixing member is good, a high gloss image is formed, and the offset resistance is good. .

  According to the second aspect of the present invention, even in the formation of an image with a small margin at the tip of the recording medium, the image peelability from the fixing member becomes better, the offset resistance becomes better, and the uneven gloss is suppressed. .

  According to the third aspect of the invention, even in the formation of an image with a small margin at the tip of the recording medium, the image peelability from the fixing member becomes better, a higher gloss image is formed, and the offset resistance becomes better. And gloss unevenness is suppressed.

  According to the fourth aspect of the present invention, even in the formation of an image with a small margin at the tip of the recording medium, the image peelability from the fixing member is good, a high gloss image is formed, and the offset resistance is good. .

  According to the fifth aspect of the present invention, the image peelability from the fixing member is good even in the formation of an image with a small margin at the tip of the recording medium, a high gloss image is formed, and the offset resistance is good. .

  According to the sixth aspect of the present invention, the image peelability from the fixing member is good even in the formation of an image with a small front end margin of the recording medium, a high gloss image is formed, and the offset resistance is good. .

  According to the seventh aspect of the invention, even when image formation is performed at high speed, the peelability of an image with a small margin at the tip of the recording medium is good, a high gloss image is formed, and offset resistance is good. Become.

  According to the eighth aspect of the invention, the image peelability from the fixing member is good even in the formation of an image with a small front margin on the recording medium, a high gloss image is formed, and the offset resistance is good. .

  According to the ninth aspect of the present invention, the image peelability from the fixing member is good even in the formation of an image with a small margin at the tip of the recording medium, a high gloss image is formed, and the offset resistance is good. .

  According to the invention of claim 10, even when image formation is performed at high speed, the peelability of an image with a small margin at the tip of the recording medium is good, a high gloss image is formed, and offset resistance is good. Become.

  According to the invention of claim 11, even when image formation is performed at a higher speed, the peelability of the image with a small margin at the tip of the recording medium is good, a high-gloss image is formed, and the offset resistance is good. It becomes.

  According to the twelfth aspect of the present invention, the image peelability from the fixing member is good even in the formation of an image with a small margin at the tip of the recording medium, a high gloss image is formed, and the offset resistance is good. .

  According to the thirteenth aspect of the present invention, even when image formation is performed at high speed, the peelability of an image with a small margin at the tip of the recording medium is good, a high gloss image is formed, and offset resistance is good. Become.

The present invention will be described in detail below.
<Toner for electrostatic image development>
The electrostatic image developing toner of the present embodiment (hereinafter sometimes simply referred to as “toner”) contains a crystalline polyester resin, an amorphous polyester resin, an aluminum element, a tin element, and a release agent. The content of aluminum element is 0.005% by mass or more and 0.060% by mass or less with respect to the whole toner, and the content of tin element is 0.12% by mass or more and 0.72% by mass or less with respect to the whole toner. The acid value of the release agent is 0 mgKOH / g or more and 5.0 mgKOH / g or less.

  When the toner has the above-described configuration, the image peelability from the fixing member is good even in the formation of an image with a small margin at the tip of the recording medium, a high gloss image is formed, and the offset resistance is good.

  The reason is not clear, but is presumed as follows.

When the aluminum element is contained in the toner, it is considered that the melt viscosity of the toner increases due to ionic crosslinking between the resins by the aluminum ions, and the high temperature offset phenomenon of the toner is suppressed.
However, if the content of the aluminum element in the toner is too large, the surface smoothness of the fixed image is lowered, which may cause a reduction in image gloss.
In order to obtain a highly glossy fixed image, it is required to reduce the viscosity of the toner, uniformly melt it, and smooth the surface of the fixed image.

  Therefore, by suppressing the content of the aluminum element in the toner to a low level, ionic crosslinking between the resins is reduced and the resin melt viscosity at the time of fixing is lowered.

However, if the content of aluminum element in the toner is lowered, the resin melt viscosity at the time of fixing decreases, so that not only the high temperature offset phenomenon may occur, but also the peelability of the image with a small margin at the tip of the recording medium. In some cases, the winding around the fixing member is likely to occur.
Here, the image having a small margin at the tip of the recording medium specifically refers to an image formed such that the shortest distance between the edge of the image formed on the surface of the recording medium and the edge of the recording medium is small. Specifically, for example, an image having the shortest distance of 1 mm may be used.
Further, when a crystalline polyester resin is contained in the toner for the purpose of improving productivity or fixing at low temperature, the occurrence of the high temperature offset phenomenon and wrapping may become remarkable.

On the other hand, when the tin element is contained in the toner, the melt viscosity of the toner is increased by ionic crosslinking between the resins by the tin ions.
Here, the aluminum element in the toner acts on the resin as trivalent or tetravalent ions, whereas the tin element acts on the resin as divalent ions. Therefore, even if the content is the same, it is considered that tin ions are weaker in cross-linking between resins than aluminum ions, and the influence on the melt viscosity of the toner is reduced.

  That is, it is considered that fine adjustment of the melt viscosity of the toner, which is difficult only by adjusting the content of the aluminum element, is facilitated by adjusting the content of the tin element. In addition, compared with aluminum ions, ion crosslinking with tin ions has a small effect on gloss, so it is considered that high-temperature offset resistance and peelability can be improved without greatly reducing gloss.

  Therefore, by adjusting the contents of the aluminum element and the tin element, it is considered that not only the high gloss image formation and the offset resistance can be achieved, but also the peelability of the image with a small front end margin of the recording medium can be realized. It is done.

  In addition, since the release agent contained in the toner has an acid value within the above range, the release agent is likely to ooze out on the image surface during image fixing, so that the peeling performance is improved and the leading edge margin of the recording medium is small. The image peelability from the fixing member is also considered to be good.

  For the reasons described above, it is presumed that the above-described effects can be obtained by using the toner having the above-described configuration.

  As described above, the content of the aluminum element is 0.005% by mass or more and 0.060% by mass or less, preferably 0.007% by mass or more and 0.060% by mass or less, and 0.007% by mass with respect to the whole toner. It is more preferably 0.055% by mass or less, and further preferably 0.007% by mass or more and 0.050% by mass or less.

  If the aluminum element content is less than 0.005% by mass, the melt viscosity of the toner is low, and high-gloss image formation is advantageous, but a high-temperature offset phenomenon may occur, and the fixable temperature range is very narrow. It may become.

  On the other hand, when the content of the aluminum element is more than 0.060% by mass, the high-temperature offset resistance performance and the peeling performance are improved, but the gloss reduction may be remarkable.

  The content of the aluminum element with respect to the entire toner can be obtained by quantitative analysis of the fluorescent X-ray intensity. Details will be described later.

  As described above, the content of the tin element is 0.12% by mass or more and 0.72% by mass or less with respect to the whole toner, preferably 0.12% by mass or more and 0.65% by mass or less, and 0.12% by mass. It is more preferably 0.60% by mass or less, and further preferably 0.15% by mass or more and 0.60% by mass or less.

  When the content of the tin element is less than 0.12% by mass, the ionic crosslinking becomes weak, and the peeling performance may not be sufficient.

  On the other hand, when the content of the tin element exceeds 0.72% by mass, the ionic cross-linking becomes strong and the peeling performance is improved, but the gloss is sometimes significantly lowered.

  The content of tin element with respect to the entire toner can be determined by quantitative analysis of the fluorescent X-ray intensity, as in the case of the aluminum element. Details will be described later.

Next, the configuration of the electrostatic image developing toner of the present embodiment will be described.
The toner for developing an electrostatic charge image of the exemplary embodiment includes at least a binder resin and a release agent, and may include additives such as a colorant and inorganic particles as necessary. The electrostatic image developing toner of this embodiment will be described in detail for each component.

(Binder resin)
The binder resin contains at least a crystalline polyester resin and an amorphous polyester resin, and may contain other resins as necessary.

―Amorphous polyester resin―
The amorphous polyester resin is a stepwise endothermic change corresponding to the glass transition (that is, the DSC curve deviates from the previous baseline and becomes a new baseline in the differential scanning calorimetry (DSC) in JIS K7121-1987. It means a polyester resin that does not show an endothermic peak corresponding to the crystalline melting point (ie, a change in DSC curve from the previous baseline, which has an endothermic peak and returns to the baseline again).

  A known polyester resin can be used as the amorphous polyester resin. The amorphous polyester resin is synthesized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In addition, as said amorphous polyester resin, a commercial item may be used and what was synthesize | combined may be used. The amorphous polyester resin may be one kind of amorphous polyester resin, but may be a mixture of two or more kinds of polyester resins.

  The polyvalent carboxylic acid and polyhydric alcohol used for the amorphous polyester resin are not particularly limited, and are, for example, monomer components described in “Polymer Data Handbook: Basic Edition” (Edition of Polymer Society, Baifukan) There are conventionally known divalent or trivalent or higher carboxylic acids and divalent or trivalent or higher alcohols.

  Specific examples of these polymerizable monomer components include divalent carboxylic acids such as succinic acid, alkyl succinic acid, alkenyl succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacin. Dibasic acids such as acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, cyclohexanedicarboxylic acid, malonic acid, mesaconic acid, and their anhydrides, These lower alkyl esters, aliphatic unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid and the like can be mentioned. Among these compounds, it is preferable that terephthalic acid is contained in an amount of 30 mol% or more of the acid component from the balance between the glass transition temperature of the polyester resin and the molecular flexibility.

  Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polyhydric alcohol include divalent alcohols such as hydrogenated bisphenol A, bisphenol derivatives such as ethylene oxide and propylene oxide adducts of bisphenol A; 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and the like. Cyclic aliphatic alcohols; linear diols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol; 1,2-propanediol, Branched diols such as 1,3-butanediol, neopentyl glycol, 2,2-diethyl-1,3-propanediol; and the like, and from the viewpoint of chargeability and strength, ethylene oxide and pro Ren'okishido adduct is preferably used.

Examples of the trihydric or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. From the viewpoint of low-temperature fixability and image gloss, a trivalent or higher crosslinkable monomer is used. The amount used is preferably 10 mol% or less of the total monomer amount. These may be used individually by 1 type and may use 2 or more types together.
If necessary, monovalent acids such as acetic acid and benzoic acid, and monovalent alcohols such as cyclohexanol and benzyl alcohol can be used for the purpose of adjusting the acid value and the hydroxyl value.

  Among these monomers, in order to improve compatibility with the crystalline polyester resin, long-chain alkyl side chains (side chains) such as 1,2-hexanediol, alkyl succinic acid and alkenyl succinic acid, and anhydrides thereof are used. It is preferable that the monomer component contains 2 to 30 mol% of a monomer having 4 or more carbon atoms. Among them, it is preferable to include alkyl succinic acid and alkenyl succinic acid having high hydrophobicity and their anhydrides.

  Examples of the alkyl succinic acid and alkenyl succinic acid and their anhydrides include, for example, n-butyl succinic acid, n-butenyl succinic acid, isobutyl succinic acid, isobutenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, Examples thereof include n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, and anhydrides and lower alkyl esters thereof.

  The number of carbon atoms of the alkyl group and alkenyl group of the alkyl succinic acid, alkenyl succinic acid and their anhydrides satisfies the suitable characteristics as the above-mentioned resin, so that the constituent monomer used in the aliphatic crystalline polyester resin described later is used. It is desirable to have more carbon atoms. Among the above, n-dodecenyl succinic acid and its anhydride are most preferable because of compatibility with the aliphatic crystalline polyester resin and ease of adjusting the glass transition temperature of the amorphous polyester resin.

  Amorphous polyester resins can be used in any combination of the above monomer components, for example, polycondensation (chemical doujin), polymer experimental studies (polycondensation and polyaddition: Kyoritsu Publishing), and polyester resin handbook (Nikkan Kogyo Shimbun). Can be synthesized by using a conventionally known method described in the company edition, etc., and a transesterification method, a direct polycondensation method, or the like can be used alone or in combination.

  Specifically, for example, at a polymerization temperature of 140 to 270 ° C., the reaction system is depressurized as necessary, and the reaction is carried out while removing water and alcohol generated during the condensation. When the monomer is not dissolved or compatible with the reaction temperature, a solvent having a high boiling point may be added as a solubilizing solvent and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. When a monomer having poor compatibility exists in the copolymerization reaction, the monomer having poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polycondensed together with the main component.

  The molar ratio (acid component / alcohol component) when the acid component reacts with the alcohol component varies depending on the reaction conditions and the like, and thus cannot be generally stated. 9/1 to 1 / 0.9. In the case of the transesterification reaction, for example, an excess of a monomer that can be distilled off under vacuum, such as ethylene glycol, propylene glycol, neopentyl glycol, and cyclohexanedimethanol, may be used.

  Examples of the catalyst used in the production of the amorphous polyester resin include antimony, tin, titanium, and aluminum catalysts. Among these, in order to contain the tin element in the toner, it is desirable to use a tin-containing catalyst such as tin, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide and the like.

By controlling the amount of the tin-containing catalyst added, the content of tin element relative to the entire toner is controlled.
Specifically, the addition amount of the tin-containing catalyst is desirably 0.1 parts by mass or more and 5.0 parts by mass or less, for example, 0.1 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the monomer component. It is more desirable to make it 0.0 parts by mass or less. By setting the addition amount of the tin-containing catalyst within the above range, the content of tin element with respect to the entire toner can be set within the above range.

  Further, the content of the aluminum element in the toner is also controlled by controlling the addition amount of the tin-containing catalyst. The reason for this is not clear, but since the ionic cross-linking between the resins is made in advance by the tin ions before entering the aggregation process, the ionic cross-linking between the resins by the aluminum ions is hindered, and the aluminum element hardly remains in the toner. It is estimated that.

  The tin-containing catalyst includes an organic tin-containing catalyst and an inorganic tin-containing catalyst. An organotin-containing catalyst is a compound having a Sn—C bond, and an inorganic tin-containing catalyst is a compound having no Sn—C bond. The tin-containing catalyst includes di-type, tri-type, and tetra-type, and the di-type is preferably used. An inorganic tin-containing catalyst is preferred.

  Examples of the inorganic tin-containing catalyst include non-branched alkyl carboxylates such as tin diacetate, tin dihexanoate, tin dioctanoate and tin distearate, tin dineopentylate and tin di (2-ethylhexyl) ate. Branched tin alkyl carboxylates, tin carboxylates such as tin oxalate, dialkoxy tin such as dioctyloxy tin and distearoxy tin, tin halides such as tin chloride and tin bromide, tin oxide and tin sulfate In particular, tin dioctanoate, tin distearate, and tin oxide are preferable.

Further, a tin-containing catalyst may be mainly used, and other catalysts may be mixed and used.
Examples of other catalysts include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; metal compounds such as zinc, manganese, antimony, titanium, zirconium, and germanium; phosphorous acid compounds; phosphorus Acid compounds; and amine compounds; specifically, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, chloride Zinc, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, zirconium tetra Rabtoxide, zirconium naphthenate, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, triphenyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, ethyl triphenylphosphonium bromide, Examples include compounds such as triethylamine and triphenylamine.

  As the molecular weight of the amorphous polyester resin, those having a weight average molecular weight (Mw) in the range of 12,000 to 150,000 can be suitably used. In particular, in order to obtain an image having a high image glossiness, the Mw is from 14,000. A range of 40,000 and a number average molecular weight Mn of 4000 to 20000 are more preferred, a Mw of 16000 to 30000, and a Mn of 5000 to 12000 are even more preferred.

  If Mw and Mn are too high, color developability may be deteriorated. If Mw and Mn are too low, image strength after fixing may be difficult to obtain, or a high temperature offset phenomenon may occur.

  Further, as the molecular weight distribution of the amorphous polyester resin, the value of Mw / Mn, which is an index of the molecular weight distribution, is preferably in the range of 2 to 10.

  In order to further improve the light on-off offset property, two types of amorphous polyester resins having different molecular weights may be used. At this time, the Mw of one kind of amorphous polyester resin is preferably in the range of 35000 to 70000, and Mn is preferably in the range of 5000 to 20000. The other amorphous polyester resin preferably has a Mw in the range of 10,000 to 25000 and a Mn in the range of 3000 to 12000.

  When two or more types of amorphous polyester resins having different molecular weights are used, it is preferable that at least one of them includes the alkyl succinic acid and alkenyl succinic acid, and their anhydrides as constituent components.

  The molecular weight and molecular weight distribution of the resin can be measured by a known method, but are generally measured by gel permeation chromatography (hereinafter abbreviated as “GPC”). Details will be described later.

The acid value of the amorphous polyester resin is desirably in the range of 5 to 25 mgKOH / g, and more desirably in the range of 7 to 20 mgKOH / g.
The acid value is measured by the potentiometric titration method of JIS K0070-1992. The same applies to the following.
The hydroxyl value measured according to JIS K0070 is preferably in the range of 5 to 40 mgKOH / g.

  The glass transition temperature of the amorphous polyester resin is preferably in the range of 30 to 90 ° C, more preferably in the range of 30 ° C to 80 ° C. Further, the temperature is more preferably in the range of 50 to 70 ° C. from the viewpoint of the balance between storage stability and toner fixing property.

  When the glass transition temperature is lower than the above range, the toner may easily cause blocking (a phenomenon in which toner particles are aggregated into a lump) during storage or in a developing device. On the other hand, if the glass transition temperature is higher than the above range, the toner fixing temperature may increase.

  The glass transition temperature of the amorphous polyester resin is measured according to JIS 7121-1987 using a differential scanning calorimeter (DSC-50 manufactured by Shimadzu Corporation). Details will be described later.

  Further, the amorphous polyester resin preferably has a softening point of 80 to 130 ° C, more preferably 90 to 120 ° C. If the softening point is less than 80 ° C., the toner and image stability of the toner after fixing and storage may be deteriorated. On the other hand, when the softening point exceeds 130 ° C., the low-temperature fixability may be deteriorated.

  Moreover, when the temperature at which the loss elastic modulus G ″ (measured at a frequency of 1 rad / s and a strain amount of 20% or less) of the amorphous polyester resin is 10,000 Pa is Tm, the Tm is in the range of 80 to 150 ° C. It is desirable that it is in the range of 70 to 120 ° C.

  If Tm is too lower than the above range, the toner may easily cause blocking (a phenomenon in which toner particles are aggregated into a lump) during storage or in the developing device. On the other hand, if Tm is higher than the above range, the toner fixing temperature may increase.

  The content of the amorphous polyester resin in the binder resin is not particularly limited, but is preferably in the range of 80 to 98% by mass, and more preferably in the range of 86 to 98% by mass with respect to the entire binder resin. If the content is less than 80% by mass, the toner strength may be reduced or the environmental stability of charging may be deteriorated. If the content is more than 98% by mass, the low-temperature fixability may not be exhibited.

―Crystalline polyester resin―
Crystalline polyester resin is used as a binder resin for toner to improve and stabilize image gloss and to improve low-temperature fixability. The crystalline polyester resin is synthesized from a divalent acid (dicarboxylic acid) component and a divalent alcohol (diol) component. In the differential scanning calorimetry (DSC) in JIS K7121-1987, the crystalline polyester resin is stepped. It does not show an endothermic change (that is, a change in the DSC curve from the previous baseline and shifts to a new baseline), but a clear endothermic peak (the DSC curve has an endothermic peak away from the previous baseline). And return to baseline again). In the case of a polymer obtained by copolymerizing other components with respect to the main chain of the crystalline polyester resin, when the other components are 50% by mass or less, this copolymer is also called a crystalline polyester resin.

  In the crystalline polyester resin, examples of the acid for becoming an acid-derived constituent component include various dicarboxylic acids, but the dicarboxylic acid as the acid-derived constituent component is not limited to one type, and two or more types of dicarboxylic acids may be used. Dicarboxylic acid-derived components may be included. Further, the dicarboxylic acid may contain a sulfonic acid group in order to improve the emulsifiability in the emulsion aggregation method.

  The “acid-derived constituent component” refers to a constituent portion that was an acid component before the synthesis of the polyester resin, and the “alcohol-derived constituent component” below is an alcohol component before the synthesis of the polyester resin. Refers to the constituent parts.

  The dicarboxylic acid is preferably an aliphatic dicarboxylic acid, and particularly preferably a linear carboxylic acid. Examples of the linear carboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10- Decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, Or lower alkyl esters and acid anhydrides thereof.

  Among the above dicarboxylic acids, those having 6 to 10 carbon atoms are preferable from the viewpoints of crystal melting point and chargeability. In order to increase the crystallinity, these linear dicarboxylic acids are preferably used in an amount of 95 mol% or more, more preferably 98 mol% or more of the acid component.

  As the acid-derived constituent component, in addition to the aliphatic dicarboxylic acid-derived constituent component, a constituent component such as a dicarboxylic acid-derived constituent component having a sulfonic acid group can be included. The dicarboxylic acid having a sulfonic acid group is effective in that it can favorably disperse a coloring material such as a pigment. Further, when the toner particles are prepared by emulsifying or suspending the entire resin in water, if the sulfonic acid group is present, it can be emulsified or suspended without using a surfactant as described later.

  Examples of the dicarboxylic acid having a sulfone group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. Among these, sodium 5-sulfoisophthalate is preferable from the viewpoint of productivity.

  The content of the dicarboxylic acid having a sulfonic acid group is preferably 2.0 constituent mol% or less, and more preferably 1.0 constituent mol% or less with respect to the entire resin. When the content of the dicarboxylic acid having a sulfonic acid group is large, the chargeability may be deteriorated. The above “constitutive mol%” refers to a percentage when each constituent component (acid-derived constituent component, alcohol-derived constituent component) in the polyester resin is 1 unit (mol).

  In the crystalline polyester resin, an aliphatic dialcohol is desirable as an alcohol to be a constituent component derived from alcohol, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-dodecanediol, 1,12-undecanediol, Examples include 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, and the like. Among them, those having 2 to 10 carbon atoms are preferable from the viewpoint of crystal melting point and chargeability. In order to enhance crystallinity, these linear dialcohols are preferably used in an amount of 95 mol% or more, more preferably 98 mol% or more of the alcohol constituent.

  Examples of other divalent dialcohols include bisphenol A, hydrogenated bisphenol A, ethylene oxide or (and) propylene oxide adducts of bisphenol A, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, diethylene glycol, Examples include propylene glycol, dipropylene glycol, 1,3-butanediol, and neopentyl glycol. These may be used individually by 1 type and may use 2 or more types together.

  If necessary, for the purpose of adjusting the acid value and hydroxyl value, for example, monovalent acids such as acetic acid and benzoic acid, monovalent alcohols such as cyclohexanol and benzyl alcohol, benzenetricarboxylic acid, Trivalent alcohols such as naphthalene tricarboxylic acid and the like, anhydrides thereof, lower alkyl esters thereof, glycerin, trimethylol ethane, trimethylol propane, and pentaerythritol can also be used.

  Other monomers are not particularly limited. For example, a conventionally known divalent or carboxylic acid which is a monomer component described in Polymer Data Handbook: Basic Edition (edited by Polymer Society: Bafukan) There are divalent alcohols. Specific examples of these monomer components include divalent carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and cyclohexanedicarboxylic acid. And dibasic acids such as these, anhydrides thereof, and lower alkyl esters thereof. These may be used individually by 1 type and may use 2 or more types together.

  The crystalline polyester resin can be synthesized according to the amorphous polyester resin. Examples of the catalyst used in the production include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; zinc, manganese, antimony, titanium, tin, zirconium, germanium, aluminum and the like Metal compounds: Phosphorous acid compounds, phosphoric acid compounds, amine compounds and the like can be mentioned, and specific examples include the following compounds.

  For example, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium Tetrapropoxide, titanium tetraisoproxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, naphthenic acid Zirconium, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, aluminum oxide Arm, triphenyl phosphite, tris (2, 4-t-butylphenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine. From the viewpoint of reactivity, antimony, tin, and titanium are desirable.

The addition amount of the catalyst is desirably 0.02 to 1.0 part by mass with respect to 100 parts by mass of the monomer component.
In order to set the content of tin element in the toner within the above range, a tin-based catalyst may be used as the catalyst, and the content of tin element may be controlled by controlling the amount of tin-based catalyst added.

  The melting point of the crystalline polyester resin is desirably in the range of 50 to 120 ° C, and more preferably in the range of 60 to 110 ° C. If the melting point is lower than 50 ° C., the storage stability of the toner and the storage stability of the toner image after fixing may become a problem. On the other hand, if the temperature is higher than 120 ° C., sufficient low-temperature fixing may not be obtained as compared with conventional toners.

  In addition, the measurement of melting | fusing point of the said crystalline polyester resin can be calculated | required as a peak temperature of the endothermic peak based on melting by the method according to the glass transition temperature measurement of the said amorphous polyester resin. Details will be described later.

  The molecular weight of the crystalline polyester resin is preferably a weight average molecular weight (Mw) in the range of 5,000 to 100,000, more preferably 10,000 from the molecular weight measurement by GPC method of the tetrahydrofuran (THF) soluble content. The number average molecular weight (Mn) is preferably in the range of 2000 to 30000, more preferably in the range of 5000 to 15000.

  If the weight average molecular weight and number average molecular weight of the crystalline polyester resin are smaller than the above ranges, it is effective for low-temperature fixability, but also softens as a resin and causes toner blocking, which adversely affects storage stability. There is a case.

  On the other hand, if the weight average molecular weight and the number average molecular weight of the crystalline polyester resin are larger than the above ranges, bleeding from the toner becomes insufficient, which may adversely affect document storage stability.

  The molecular weight distribution Mw / Mn of the crystalline polyester resin is preferably in the range of 1.5 to 20, more preferably in the range of 2 to 5.

  The acid value of the crystalline polyester resin is desirably in the range of 4 to 20 mgKOH / g, and more desirably in the range of 8 to 15 mgKOH / g. Further, the hydroxyl value is desirably in the range of 3 to 30 mgKOH / g, and more desirably in the range of 50 to 10 mgKOH / g.

  The content of the crystalline polyester resin in the binder resin is preferably in the range of 2 to 20% by mass, and more preferably in the range of 2 to 14% by mass. When the addition amount of the crystalline polyester resin is more than 20% by mass, the domain size of the crystalline polyester resin becomes large and is easily exposed on the toner surface, which may cause a decrease in toner powder fluidity and a deterioration in chargeability. . If the content of the crystalline polyester resin in the binder resin is less than 2% by mass, good low-temperature fixability may not be obtained.

―Other resins―
In addition to the amorphous polyester resin and the crystalline polyester resin, other resins can be used in combination with the binder resin. Examples of other resins include other amorphous resins and other crystalline resins.

Examples of other amorphous resins include polystyrene, poly (meth) acrylic acid and esterified products thereof.
Specifically, for example, styrenes such as styrene, parachlorostyrene, α-methylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-acrylic acid 2- Esters having a vinyl group such as ethylhexyl, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate; vinyl nitriles such as acrylonitrile and methacrylonitrile; vinyl methyl ether, vinyl Polymers of monomers such as vinyl ethers such as isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; polyolefins such as ethylene, propylene and butadiene; A copolymer obtained by combining the above or a mixture thereof can be mentioned, and further, an epoxy resin, a polyester resin, a polyurethane resin, a polyamide resin, a cellulose resin, a polyether resin, etc., a non-vinyl condensation resin, or these and the above-mentioned Mixtures with vinyl resins and graft polymers obtained when polymerizing vinyl monomers in the presence of these can also be used. Among these, styrene acrylic copolymer resins, particularly styrene butyl acrylate copolymer resins are preferable from the viewpoint of chargeability and fixability.

  Examples of other crystalline resins include amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, and (meth) acrylic acid. Decyl, undecyl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, oleyl (meth) acrylate, behenyl (meth) acrylate Examples thereof include vinyl resins in which long chain alkyls such as alkenyl (meth) acrylic acid esters are used alone or in combination of two or more, and olefins such as ethylene, propylene, butadiene and isoprene.

  The content of other resins in the binder resin is desirably less than 3% by mass.

The binder resin preferably has an insoluble content of tetrahydrofuran (hereinafter abbreviated as “THF”) of 0 to 20%. When the THF insoluble content is 20% or more, the offset resistance is improved, but the glossiness of the image may be impaired, and the OHP light transmittance may be impaired.
The THF insoluble matter can be determined by dissolving the resin in THF so as to have a concentration of about 10% by mass, filtering with a membrane filter or the like, drying the filter residue, and measuring the mass.

(Release agent)
As described above, the release agent contained in the toner of the exemplary embodiment has an acid value of 0 mgKOH / g or more and 5.0 mgKOH / g or less, preferably 0 mgKOH / g or more and 4.5 mgKOH / g or less, and 0 mgKOH / g or more. 4.3 mgKOH / g or less is more desirable, and 0 mgKOH / g or more and 4.0 mgKOH / g or less is more desirable.

  If the acid value of the release agent is greater than 5.0 mgKOH / g, ion release between the release agent and aluminum ions or ion release between the release agent and tin ions tends to occur. Therefore, not only does the release agent not easily leach out to the image surface during image fixing, but also the ion crosslinking of the resin and aluminum ions or the ion crosslinking of the resin and tin ions may be inhibited.

Specific examples of the release agent having an acid value in the above range include, for example, low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; silicones having a softening point; oleic acid amide, erucic acid amide, and ricinoleic acid amide. , Fatty acid amides such as stearamide; plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; montan wax, ozokerite, ceresin, paraffin wax, Mineral and petroleum waxes such as microcrystalline wax and Fischer-Tropsch wax; ester waxes of higher fatty acids and higher alcohols such as stearyl stearate and behenyl behenate; butyl stearate, propyl oleate, monostearate Ester waxes of higher fatty acids such as acid glycerides, distearate glycerides, pentaerythritol tetrabehenate and unitary or polyhydric lower alcohols; diethylene glycol monostearate, dipropylene glycol distearate, distearic diglyceride, tetrastearic acid Examples include ester waxes composed of higher fatty acids such as triglycerides and polyhydric alcohol multimers; sorbitan higher fatty acid ester waxes such as sorbitan monostearate; cholesterol higher fatty acid ester waxes such as cholesteryl stearate.
In the present invention, these release agents may be used alone or in combination of two or more.

  The melting point of the release agent is preferably 40 ° C. or higher and 150 ° C. or lower, and more preferably 70 ° C. or higher and 110 ° C. or lower.

The amount of the release agent added is preferably in the range of 5 to 25 parts by mass, more preferably in the range of 7 to 20 parts by mass with respect to 100 parts by mass of the binder resin.
When the addition amount of the release agent is less than the above range, the release property from the fixing member is insufficient at the time of fixing, and an offset is likely to occur.
On the other hand, when the amount of the release agent added is larger than the above range, adverse effects such as deterioration of color developability and decrease in transparency tend to occur.

  On the other hand, if the content of the release agent is too large, the color fixing image surface or the internal release agent may deteriorate the OHP projectability. When used as a two-component developer, it is also conceivable that the release agent moves to the carrier due to the rubbing between the toner and the carrier, and the charging performance of the developer changes over time. Further, when used as a one-component developer, it is conceivable that the release agent moves to the blade due to friction between the toner and the charging blade, and the charging performance of the developer changes over time. In addition, the fluidity of the toner may be deteriorated. As described above, when the content of the release agent is too large, color image quality and reliability may be deteriorated.

(Coloring agent)
The toner of the exemplary embodiment includes a colorant as necessary.
There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is used. Specific examples include the following colorants.

  Examples of yellow pigments include yellow lead, zinc yellow, yellow iron oxide, cadmium yellow, chrome yellow, hansa yellow, hansa yellow 10G, benzidine yellow G, benzidine yellow GR, selenium yellow, quinoline yellow, permanent yellow NCG, and the like. In particular, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 180, C.I. I. Pigment Yellow 185 or the like is preferably used.

  Examples of magenta pigments include Bengala, Cadmium Red, Lead Red, Mercury Sulfide, Watch Young Red, Permanent Red 4R, Resol Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C Pigment Red 31, 146, 147, 150, 176, 238, 269, and the like as Rose Bengal, Eoxin Red, Alizarin Lake, and Naphthol pigments. Pigments include quinacridone pigments. Examples thereof include Red 122, 202, and 209. Among these, Pigment Red 185, 238, 269, and 122 are particularly preferable from the viewpoints of manufacturability and chargeability.

  Cyan pigments include bitumen, cobalt blue, alkali blue lake, Victoria blue lake, fast sky blue, induslen blue BC, aniline blue, ultramarine blue, chalcoil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare. Rate, and the like. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 or the like is preferably used.

  Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, benzidine orange G, indanthrene brilliant orange RK, and indanthrene brilliant orange GK. Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake. Examples of the green pigment include chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G, and the like.

  Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.

  Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenyl Various dyes such as methane, diphenylmethane, thiazine, thiazole, and xanthene are also used. These colorants are used alone or in combination.

  Examples of the black pigment used for the black toner include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon and the like, and carbon black is particularly preferably used. Since carbon black has relatively good dispersibility, it does not require any special dispersion, but it is desirable that it be produced by a production method according to the colorant.

  The colorant is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner. The colorant is preferably added in the range of 4 to 15% by mass with respect to the total toner mass. Further, when a magnetic material or the like is used as the black colorant, it can be added at 12 to 240% by mass, unlike other colorants. Specifically, a material that is magnetized in a magnetic field is used, but a ferromagnetic powder such as iron, cobalt, or nickel, or a compound such as ferrite or magnetite is used. When obtaining toner in the aqueous phase, it is necessary to pay attention to the aqueous phase migration of the magnetic material, and it is desirable to modify the surface of the magnetic material in advance, for example, to perform a hydrophobic treatment or the like.

  The content of the colorant in the toner is preferably as large as possible within a range that does not impair the smoothness of the image surface after fixing. Increasing the content of the colorant is advantageous from the viewpoint of suppressing the offset phenomenon because the image thickness can be reduced when images having the same density are obtained.

(Silicon oxide particles)
The toner according to the exemplary embodiment preferably further includes silicon oxide particles, and the dispersion ratio of the silicon oxide particles is desirably 80% or more and 100% or less.

  Here, the dispersion ratio of the silicon oxide particles is a value indicating how much the silicon oxide particles contained in the toner are dispersed in the toner, and is specifically defined as follows.

First, fluorescent X-ray measurement is performed in a randomly selected region of 1 μm ² in the cross section of the toner particles, and the fluorescent X-ray intensity corresponding to the silicon element with respect to the fluorescent X-ray intensity (I _C ) corresponding to the carbon element. obtaining an intensity ratio _{(I Si) (I Si /} I C).

Next, in the cross section of the toner particles, another 1 μm ² region is randomly selected, and the above measurement is performed for a total of 100 regions.

Of the 100 regions, the ratio of the region where the intensity ratio (I _Si / I _C ) value is 0.07 or more and 0.12 or less is defined as “dispersion rate of silicon oxide particles”.

  Therefore, the higher the dispersion ratio of the silicon oxide particles, the more uniformly the silicon oxide particles are dispersed in the toner. Further, the lower the dispersion ratio of the silicon oxide particles, the more the silicon oxide particles are unevenly distributed in the toner, or the smaller the content of the silicon oxide particles in the toner. A specific method for measuring “dispersion rate of silicon oxide particles” will be described later.

  When the dispersion ratio of the silicon oxide particles is within the above range, the image peelability from the fixing member is improved even in the formation of an image with a small front end margin of the recording medium, the offset resistance is improved, and the fixed image The gloss unevenness is suppressed.

The reason is not clear, but is presumed as follows.
It is considered that the response of the toner to heat is accelerated by including the silicon oxide particles inside the toner. That is, after the heat is applied to the toner, the time until the binder resin contained in the toner is melted is shortened, so that the image can be peeled off from the fixing member with a small front end margin of the recording medium. It is considered that the offset resistance becomes better.

  Further, since the viscoelastic behavior of the toner is controlled by including the silicon oxide particles in the toner, the peelability of the image having a small front end margin of the recording medium from the fixing member is improved, and the offset resistance is further improved. It is also considered to be good.

  However, since inorganic particles of several nm to several tens of nm originally tend to aggregate and often have low compatibility with the binder resin contained in the toner, it is difficult to disperse as primary particles in the toner. There are many cases where it is dispersed in the secondary aggregation state.

  Even if the silicon oxide particles are contained in the toner in an appropriate amount as a whole, when the silicon oxide particles are unevenly distributed in the toner, that is, when the dispersion ratio of the silicon oxide particles is out of the above range, the entire toner is It is conceivable that the effect of the silicon oxide particles as described above cannot be obtained or gloss unevenness occurs.

Specifically, in the fluorescent X-ray measurement in the region of 1 μm ^{2, in} the region where the value of the intensity ratio (I _Si / I _C ) is less than 0.07, the concentration of silicon oxide particles in the region is too low. In the region, the above effect may not be obtained partially.

On the contrary, in the region where the value of the intensity ratio (I _Si / I _C ) exceeds 0.12, the concentration of silicon oxide particles in the region is too high, so that the gloss is partially lowered in the region. There is.

When there are many regions in the toner where the value of the intensity ratio (I _Si / I _C ) is less than 0.07 or exceeds 0.12, the region where the effect of silicon oxide particles is not obtained and the gloss is low. There will be many areas. Therefore, it is considered that the effect of the silicon oxide particles as described above cannot be obtained as a whole, or gloss unevenness may occur even if the effect as a whole is obtained.

  For the above reasons, when the dispersion ratio of the silicon oxide particles is in the above range, the image peelability from the fixing member becomes better even in the formation of an image with a small margin at the tip of the recording medium, and the offset resistance is further improved. It is presumed that the gloss is improved and the uneven gloss of the fixed image is suppressed.

  In addition, when the dispersion ratio of the silicon oxide particles is in the above range, a resin having a lower glass transition temperature can be used as the amorphous polyester resin contained in the binder resin, thereby improving the low-temperature fixability of the toner. Can be made. This is because the heat blocking resistance is not impaired even when a resin having a low glass transition temperature is used because the dispersion ratio of silicon oxide is in the above range.

  The reason for this is not clear, but by containing dispersed silicon oxide particles, the storage elastic modulus in the glassy state increases, and the movement by diffusion of low molecular weight components of the binder resin is suppressed by the particles. It is estimated that

  The silicon oxide particles may be appropriately synthesized by a known method such as a gas phase method or a wet method, or a commercially available one may be used.

The silicon oxide particles may be surface-treated with a hydrophobizing agent or the like.
As the hydrophobizing agent, for example, a silane coupling agent, a titanate coupling agent, silicone oil, silicone varnish, or the like can be used.

  Examples of silane coupling agents include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, benzyldimethylchlorosilane, methyltrimethoxysilane, methyltriethoxysilane, and isobutyl. Trimethoxysilalan, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-butyltrimethoxysilane, n-hexylmethoxysilane, n-octyltrimethoxysilane, n-hexadecyltrimethoxysilane, n- Octadecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, etc. Can be used.

  Moreover, as a silicone oil, dimethyl polysiloxane, methyl hydrogen polysiloxane, methylphenyl polysiloxane, etc. can be used, for example.

  The volume average particle size of the silicon oxide particles is desirably 5 nm or more and 100 nm or less, and more desirably 6 nm or more and 50 nm or less.

  The addition amount of silicon oxide particles is preferably 1% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 8% by mass or less, and more preferably 1% by mass or more and 6% by mass or less with respect to the whole toner. It is further desirable that

  When the addition amount of the silicon oxide particles is within the above range, even in the formation of an image with a small margin at the tip of the recording medium, the image peelability from the fixing member becomes better, a higher gloss image is formed, and the offset resistance And the gloss unevenness of the fixed image is further suppressed.

(Other ingredients)
In addition to the above-described components, various components such as an internal additive, a charge control agent, and an external additive can be further added to the toner of the exemplary embodiment as necessary.

  Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals.

  When the magnetic material is contained and used as a magnetic toner, the ferromagnetic material preferably has a volume average particle size of 2 μm or less, more preferably 0.1 μm or more and 0.5 μm or less.

  The amount of the internal additive contained in the toner is preferably 20 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the resin component, and particularly preferably 40 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the resin component.

  In addition, the internal additive has a magnetic property of 10 Oersted to 300 Oersted, a saturation magnetization (σs) of 50 emu / g to 200 emu / g, a residual magnetization (σr) of 2 emu / g to 20 emu when applied with 10 K Oersted. / G or less is desirable.

  Examples of the charge control agent include salicylic acid metal salts, metal-containing azo compounds, nigrosine and quaternary ammonium salts. The charge control agent is generally used for the purpose of improving the chargeability.

  Examples of the external additive include the following inorganic particles and organic particles.

Inorganic particles are generally used for the purpose of improving fluidity.
Examples of inorganic particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, selenium chloride, Examples include Bengala, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, and silicon nitride.

Among the inorganic particles, titanium-based particles and silica particles are preferable, and hydrophobized fine particles are particularly preferable.
The primary particle diameter of the inorganic particles is preferably 1 to 1000 nm, and the addition amount is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the toner.

  Examples of the organic particles include polystyrene, polymethyl methacrylate, and polyvinylidene fluoride. Those obtained by treating the surface of these particles with a silicone compound or a fluorine compound can also be preferably used. Organic particles are generally used for the purpose of improving cleaning properties and transferability.

(Physical properties of toner)
The volume average particle size of the toner is preferably 1.0 μm or more and 20 μm or less, more preferably 2.0 μm or more and 8.0 μm or less, and further preferably 4.0 μm or more and 8.0 μm or less. The number average particle size is preferably 10 μm or less, more preferably 2.0 μm or more and 8.0 μm or less, and further preferably 4.0 μm or more and 8.0 μm or less.

(Toner production method)
The toner is produced in an acidic or alkaline aqueous medium such as an aggregation coalescence method, suspension polymerization method, dissolution suspension granulation method, dissolution suspension method, dissolution emulsion aggregation aggregation method, etc. Although it is suitable to manufacture by a wet manufacturing method, the aggregation coalescence method is especially desirable.

  A toner manufacturing method using an aggregation and coalescence method includes, for example, a resin particle dispersion in which first particle particles having a particle diameter of 1 μm or less are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a mold release A first aggregating step of mixing a release agent particle dispersion in which agent particles are dispersed to form core agglomerated particles including the first resin particles, the colorant particles, and the release agent particles; Forming a shell layer containing second resin particles on the surface of the core agglomerated particles to obtain core / shell agglomerated particles; and the core / shell agglomerated particles as the first resin particles or the second agglomerated particles. And a fusion / union step of fusing and uniting by heating above the glass transition temperature of the resin particles.

  In order to make the dispersion ratio of the silicon oxide particles in the toner within the above range, the silicon oxide particles are dispersed in the first resin particles instead of the resin particle dispersion before the first aggregation step. It is desirable to use a resin silica particle dispersion in which the resin silica particles are dispersed.

  That is, a toner production method using the resin silica particle dispersion includes a resin silica particle dispersion in which resin silica particles having a particle diameter of 1 μm or less are dispersed, and a colorant particle dispersion in which colorant particles are dispersed. A first aggregating step of mixing a release agent particle dispersion in which release agent particles are dispersed to form core aggregated particles including the resin silica particles, the colorant particles, and the release agent particles; A second aggregating step of forming a shell layer containing second resin particles on the surface of the core agglomerated particles to obtain core / shell agglomerated particles; and the core / shell agglomerated particles as the resin silica particles or the second resin. And a fusion / union process in which the particles are heated to a temperature equal to or higher than the glass transition temperature of the particles.

  Hereinafter, each step will be described in detail.

-Preparation of dispersion-
In the above aggregation and coalescence method, for example, a resin particle dispersion (resin silica particle dispersion), a colorant particle dispersion, and a release agent particle dispersion are prepared.

  As a method for adjusting the resin particle dispersion, for example, a phase inversion emulsification method can be used. In the phase inversion emulsification method, a resin to be dispersed is dissolved in an organic solvent in which the resin is soluble, a neutralizing agent or a dispersion stabilizer is added as necessary, and an aqueous solvent is added dropwise with stirring. Then, after obtaining the emulsified particles, the organic solvent in the resin particle dispersion is removed to obtain an emulsion (resin particle dispersion). At this time, the order of adding the neutralizing agent and the dispersion stabilizer may be changed.

As a method for preparing the resin silica particle dispersion, a resin silica particle dispersion is obtained by the same method as that for the resin particle dispersion except that the silicon oxide particles are added to the organic solvent simultaneously with the resin to be dispersed. Can do.

  Examples of the organic solvent (resin dissolving solvent) for dissolving the resin include formic acid esters, acetic acid esters, butyric acid esters, ketones, ethers, benzenes, and halogenated carbons.

  Specifically, alkyl (methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, etc.) esters such as formic acid, acetic acid, butyric acid, acetone, MEK, MPK, MIPK, Methyl ketones such as MBK and MIBK, ethers such as diethyl ether and diisopropyl ether, heterocyclic substituents such as toluene, xylene and benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2- Halogenated carbons such as trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, etc. can be used singly or in combination of two or more, but they are easily available, easy to recover during solvent removal, From the point of consideration, acetates, methyl ketones, Le acids is usually preferably used, in particular, acetone, methyl ethyl ketone, acetic acid, ethyl acetate, butyl acetate is preferred. If the organic solvent remains in the resin particles, it may become a VOC causative substance, and therefore, it is preferable to use a solvent having a relatively high volatility.

  As the aqueous solvent, ion-exchanged water is basically used, but a water-soluble organic solvent may be included so as not to destroy the oil droplets.

  Examples of the water-soluble organic solvent include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, and other short carbon chain alcohols; ethylene glycol monomethyl ether, Examples include ethylene glycol monoalkyl ethers such as ethylene glycol monoethyl ether and ethylene glycol monobutyl ether; ethers, diols, THF, acetone and the like.

The mixing ratio of these water-soluble organic solvents to ion-exchanged water is selected in the range of 1% to 50%, more preferably 1% to 30%, and used as the aqueous component.
In addition, the water-soluble organic solvent may be added to the resin solution and used in addition to the ion-exchanged water to be added. In the case of adding a water-soluble organic solvent, the wettability between the resin and the resin dissolving solvent can be adjusted, and a function of reducing the liquid viscosity after the resin is dissolved can be expected.

  Moreover, you may add a dispersing agent to a resin solution and an aqueous component as needed so that the said emulsion may maintain a dispersed state stably.

Examples of the dispersant are those that form a hydrophilic colloid in an aqueous component, and in particular, cellulose derivatives such as hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose; polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyacrylic. Examples thereof include synthetic polymers such as acid salts and polymethacrylates, and dispersants such as gelatin, gum arabic and agar.
Moreover, solid fine powders, such as a silica, a titanium oxide, an alumina, a tricalcium phosphate, a calcium carbonate, a calcium sulfate, barium carbonate, can be used as a dispersing agent, for example.

  These dispersants are usually added so that the concentration in the aqueous component is 0 to 20% by mass, preferably 0 to 10% by mass.

A surfactant is also used as the dispersant.
As examples of the surfactant, those according to those used in the colorant dispersion described later can be used.

  As surfactants, for example, in addition to natural surfactant components such as saponins, cationic surfactants such as alkylamine hydrochlorides / acetates, quaternary ammonium salts, glycerols, fatty acid soaps, sulfates, alkyls Anionic surfactants such as naphthalene sulfonates, sulfonates, phosphoric acid, phosphate esters, sulfosuccinates and the like can be mentioned, and anionic surfactants and nonionic surfactants are preferably used.

  In order to adjust the pH of the emulsion, a neutralizing agent may be added. As the neutralizing agent, general acids such as nitric acid, hydrochloric acid, sodium hydroxide and ammonia, and alkalis can be used.

  As a method for removing the organic solvent from the emulsion, a method of volatilizing the organic solvent at room temperature (15 ° C. or higher and 35 ° C. or lower) or heating, and a method of combining this with reduced pressure are preferably used.

The volume average particle size of the resin particles in the resin particle dispersion thus obtained is 1 μm or less in order to make it easy to adjust the volume average particle size and particle size distribution of the toner particles to desired values. It is desirable that it is 100 nm or more and 300 nm or less.
The volume average particle diameter of the resin particles can be measured, for example, with a laser diffraction particle size distribution measuring apparatus (LA-700, manufactured by Horiba, Ltd.).

  The solid content in the resin particle dispersion is preferably 5 parts by weight or more and 40 parts by weight or less, more preferably 10 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the resin particle dispersion. More preferably, it is 15 to 25 parts by mass.

  If the solid content is less than 5 parts by mass, the viscosity of the resin particle dispersion is lowered, which may deteriorate the stability of the particles or may be undesirable in terms of cost during transportation. On the other hand, if the solid content exceeds 40 parts by mass, the viscosity increases excessively, the uniformity of stirring is lost, and polymerization may not proceed well, which may be inconvenient.

The colorant particle dispersion is prepared by a known method. For dispersion of the colorant particles, for example, a rotary shear type homogenizer, a media type disperser such as a ball mill, a sand mill, or an attritor, a high-pressure opposed collision type dispersion is used. A machine or the like is preferably used.
Also, a colorant particle dispersion can be prepared by using a polar ionic surfactant and dispersing it in an aqueous solvent using a homogenizer as described above.

  The volume average particle diameter of the colorant particles in the colorant particle dispersion is desirably 1 μm or less in order to facilitate adjusting the volume average particle diameter and particle size distribution of the toner particles to desired values. It is more desirable that the thickness be 100 nm or more and 300 nm or less.

  The release agent particle dispersion includes, for example, an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, and the above release agent dispersed in water, heated to a temperature higher than the melting temperature, For example, a release agent dispersion containing release agent particles having a particle diameter of 1 μm or less can be prepared by adjusting the particle size with a homogenizer or a pressure discharge type dispersing machine.

  The volume average particle size of the release agent particles in the release agent particle dispersion is 1 μm or less in order to easily adjust the volume average particle size and particle size distribution of the toner particles to desired values. Desirably, it is more desirably 100 nm or more and 300 nm or less.

A surfactant can be used for the purpose of stabilizing the dispersion of each dispersion.
Examples of the surfactant include anionic surfactants such as sulfate, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol And nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, an ionic surfactant is preferable, and an anionic surfactant and a cationic surfactant are more preferable. The said surfactant may be used individually by 1 type, and may be used in combination of 2 or more type.

  Specific examples of anionic surfactants include, for example, fatty acid soaps such as potassium laurate, sodium oleate, and castor oil sodium; sulfate esters such as octyl sulfate, lauryl sulfate, lauryl ether sulfate, and nonylphenyl ether sulfate; Sodium alkylnaphthalene sulfonate such as lauryl sulfonate, dodecyl benzene sulfonate, triisopropyl naphthalene sulfonate, dibutyl naphthalene sulfonate; naphthalene sulfonate formalin condensate, monooctyl sulfosuccinate, dioctyl sulfosuccinate, lauric acid amide sulfonate, oleic acid amide sulfonate, etc. Sulfonates: lauryl phosphate, isopropyl phosphate, nonylphenyl Phosphoric acid esters such as chromatography ether phosphates; dialkyl sulfosuccinate salts such as sodium dioctyl sulfosuccinate; sulfosuccinate salts such as sulfosuccinate lauryl disodium; and the like.

  Specific examples of the cationic surfactant include amine salts such as laurylamine hydrochloride, stearylamine hydrochloride, oleylamine acetate, stearylamine acetate, stearylaminopropylamine acetate; lauryltrimethylammonium chloride, dilauryl Dimethylammonium chloride, distearyldimethylammonium chloride, distearyldimethylammonium chloride, lauryldihydroxyethylmethylammonium chloride, oleylbispolyoxyethylenemethylammonium chloride, lauroylaminopropyldimethylethylammonium ethosulphate, lauroylaminopropyldimethylhydroxyethylammonium perchlorate , Alkylbenzene trimethyl ammonium chlora De, quaternary ammonium salts such as alkyl trimethyl ammonium chloride; and the like.

  Specific examples of the nonionic surfactant include alkyl ethers such as polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octyl phenyl ether, Alkylphenyl ethers such as polyoxyethylene nonylphenyl ether; alkyl esters such as polyoxyethylene laurate, polyoxyethylene stearate, polyoxyethylene oleate; polyoxyethylene lauryl amino ether, polyoxyethylene stearyl amino ether, poly Alkylamines such as oxyethylene oleyl amino ether, polyoxyethylene soybean amino ether, polyoxyethylene beef tallow amino ether; Alkylamides such as reoxyethylene lauric acid amide, polyoxyethylene stearic acid amide, polyoxyethylene oleic acid amide; vegetable oil ethers such as polyoxyethylene castor oil ether, polyoxyethylene rapeseed oil ether; lauric acid diethanolamide, Alkanolamides such as stearic acid diethanolamide and oleic acid diethanolamide; sorbitan esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmiate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate Ethers; and the like.

  The content of the surfactant in each dispersion may be a level that does not inhibit the present invention, generally a small amount, specifically, a range of about 0.01 to 10% by mass is desirable. More preferably, it is the range of 0.05 to 5 mass%, More preferably, it is the range of about 0.1 to 2 mass%. When the content of the surfactant is less than 0.01% by mass, each dispersion such as a resin particle dispersion, a colorant dispersion, and a release agent dispersion becomes unstable, which causes aggregation. Since the stability between the particles is different at the time of agglomeration, problems such as the release of specific particles may occur. On the other hand, if the surfactant content exceeds 10% by mass, the particle size distribution of the particles may become wide, and the particle size may be difficult to control. In general, a suspension polymerization toner dispersion having a large particle size is stable even if the amount of the surfactant used is small.

-Aggregation process-
In the first flocculation step, the dispersion liquid prepared separately and the raw material dispersion liquid in which other dispersion liquids are mixed as needed are heated to form agglomerated particles (core agglomerated particles) having a diameter substantially close to the desired toner diameter. ). Aggregated particles are formed by heteroaggregation or the like. For the purpose of stabilizing the aggregated particles and controlling the particle size / size distribution, the ionic surfactant having a polarity different from that of the aggregated particles or a monovalent or higher charge such as a metal salt is used. A compound having is added.

  In the second aggregating step, the second resin particles are adhered to the surface of the core agglomerated particles obtained in the first aggregating step by using a resin particle dispersion containing the second resin particles, and the desired thickness is obtained. By forming the coating layer (shell layer), aggregated particles (core / shell aggregated particles) having a core / shell structure in which a shell layer is formed on the surface of the core aggregated particles are obtained. In addition, the 2nd resin particle used in this case may be the same as the 1st resin particle, and may differ.

  In the first aggregation step, the balance of the amounts of the two polar ionic surfactants (dispersants) contained in the resin particle dispersion and the colorant particle dispersion can be shifted in advance. For example, an inorganic metal salt such as calcium nitrate or a polymer of an inorganic metal salt such as barium sulfate is ionically neutralized and heated below the glass transition temperature of the first resin particles to form core agglomerated particles. Can be produced.

  In such a case, in the second agglomeration step, the resin particle dispersion treated with the dispersant having the polarity and the amount so as to compensate for the deviation in the balance between the two polar dispersants as described above is used for the core agglomeration. A core / shell aggregated particle is prepared by adding to a solution containing the particles and, if necessary, slightly heating below the glass transition temperature of the core aggregated particle or the second resin particle used in the second aggregation step. be able to. In addition, the 1st and 2nd aggregation process may be repeatedly performed in several steps dividedly.

  In the toner manufacturing method of the present embodiment, particles can be prepared by generating aggregation due to pH change in the aggregation process. At the same time, a flocculant is added in order to stably and rapidly aggregate the particles, or to obtain agglomerated particles having a narrower particle size distribution.

  The flocculant is not particularly limited, and a metal salt of an inorganic acid is used as the flocculant in consideration of the stability of the flocculent particles, the stability of the flocculant with respect to heat and time, and removal during washing. Specific examples include metal salts of inorganic acids such as magnesium chloride, sodium chloride, aluminum sulfate, calcium sulfate, ammonium sulfate, aluminum nitrate, silver nitrate, copper sulfate, and sodium carbonate. In the present invention, final toner particles From the viewpoint of controlling the viscosity at the time of fixing, an aggregating agent containing aluminum (for example, polyaluminum chloride, aluminum sulfate, potassium alum, etc.) is used.

  The amount of the flocculant added varies depending on the valence of the charge, but the amount is small, and in the case of trivalent such as aluminum, it is about 0.5% by mass or less. Since the amount of the flocculant is preferably small, it is preferable to use a compound having a large valence.

  As the means for controlling the aluminum content in the toner in this embodiment, a method of controlling the aluminum content in the toner by adjusting the amount of the aluminum-containing flocculant such as polyaluminum chloride and aluminum sulfate used in the aggregation step. At the end of the agglomeration process, a suitable amount of a so-called chelating agent such as EDTA (ethylenediaminetetraacetic acid), DTPA (diethylenetriaminepentaacetic acid), NTA (nitrilotriacetic acid) is added, and aluminum ions are trapped and formed in the washing process, etc. And a method of removing the complex salt.

In the present embodiment, since the control of removal of the generated complex and the amount of trapping is complicated by the trapping by the chelating agent, a method of controlling by the addition amount of the Al-containing flocculant is preferable.
When the aluminum content in the toner is controlled by the addition amount of the Al-containing flocculant, the addition amount of the Al-containing flocculant is 0.1% by mass or more and 5.0% by mass or less with respect to the entire solid content of the mixed solution. It is desirable that it be 0.1 mass% or more and 3.0 mass% or less.

―Fusion and unity process―
Next, in the fusion / unification step, the core / shell aggregated particles obtained through the second aggregation step are used as a first or second resin particle contained in the core / shell aggregated particles in a solution. The toner particles are obtained by heating above the glass transition temperature (if the resin type is two or more, the glass transition temperature of the resin having the highest glass point transition temperature), and fusing and coalescing.

  After completion of the coalescence / unification process, toner particles formed in the solution are dried through a known washing process, solid-liquid separation process, and drying process to obtain toner particles.

  In addition, as for a washing | cleaning process, it is desirable to perform substitution washing | cleaning by ion-exchange water fully from a charging point. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, etc. are preferably used from the viewpoint of productivity. Furthermore, the drying process is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used.

―Addition of external additives―
Toner is obtained by mixing the toner particles obtained as described above with external additives and other additives as required. Mixing can be performed, for example, by a known mixer such as a V-type blender, a Henschel mixer, or a Redige mixer.

Moreover, as other additives, various additives can be used as needed. Examples thereof include a cleaning aid or a transfer aid such as a fluidizing agent, polystyrene particles, polymethyl methacrylate particles, and polyvinylidene fluoride particles.

<Developer for developing electrostatic image>
The developer for developing an electrostatic charge image in the present exemplary embodiment (hereinafter sometimes abbreviated as “developer”) includes at least a toner, and may include a carrier as necessary. That is, the developer may be a one-component developer or a two-component developer. The toner is the electrostatic charge developing toner of this embodiment. Hereinafter, the developer in the present embodiment will be described.

(Career)
There is no restriction | limiting in particular as a carrier, A well-known carrier can be used. Examples of the carrier include a magnetic metal such as iron oxide, nickel and cobalt, a magnetic oxide such as ferrite and magnetite, and a resin-coated carrier having a resin coating layer in which a carrier coating resin is coated on the surface of the carrier core material. Can do. The carrier may be a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin.

―Coated resin carrier―
[Carrier core]
The carrier core material (hereinafter sometimes simply referred to as “core material”) has a volume electric resistance of “1 × 10 ^7.5 Ω · cm” or more and “1 × 10 ^9.5 Ω · cm” or less. It is desirable. When the volume electric resistance is less than “1 × 10 ^7.5 Ω · cm”, when the toner concentration in the developer is reduced by repeated copying, charges are injected into the carrier, and the carrier itself is developed. There is a risk of it. On the other hand, if the volume electric resistance is larger than “1 × 10 ^9.5 Ω · cm”, the image quality such as a prominent edge effect and pseudo contour may be adversely affected.

  Although the core material is not particularly limited, it is desirable to satisfy the above conditions, for example, magnetic metals such as iron, steel, nickel, cobalt, alloys of these with manganese, chromium, rare earth, ferrite, magnetite, etc. And the like. Among these, ferrite, particularly alloys with manganese, lithium, strontium, magnesium and the like are desirable from the viewpoint of core surface properties and core material resistance.

  The volume average particle size of the core material is desirably 10 μm or more and 500 μm or less, and more desirably 30 μm or more and 100 μm or less.

[Carrier coating resin]
Carrier coating resins include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic acid copolymer, organosiloxane. Examples include straight silicone resin composed of a bond or a modified product thereof, fluororesin, polyester, polycarbonate, phenol resin, epoxy resin, and the like, but are not limited thereto.

  The fluorine-based resin can be appropriately selected depending on the purpose, and examples thereof include fluorine-based resins such as polytetrafluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, and polychlorotrifluoroethylene. These may be used individually by 1 type and may use 2 or more types together.

Desirably, resin particles, conductive particles, and the like are dispersed in the coating film formed of the coating resin.
When the resin particles are dispersed in the coating film, they are uniformly dispersed in the thickness direction and the tangential direction of the carrier surface. Surface formation similar to that at the time of use can be maintained, and good charge imparting ability for the toner can be maintained over a long period of time.
Further, when conductive particles are dispersed in the coating film, since the conductive particles are uniformly dispersed in the thickness direction and the tangential direction of the carrier surface, the carrier film is used for a long period of time. Even when the surface is worn, it is possible to always maintain the same surface formation as when not in use, and to prevent carrier deterioration for a long time.
In addition, when the resin particle and electroconductive particle are disperse | distributed to a coating film, the above-mentioned effect can be show | played simultaneously.

  Examples of the resin particles include thermoplastic resin particles and thermosetting resin particles. Among these, a thermosetting resin is desirable from the viewpoint of relatively easily increasing the hardness, and resin particles of a nitrogen-containing resin containing N atoms are desirable from the viewpoint of imparting negative chargeability to the toner. In addition, these resin particles may be used individually by 1 type, and may use 2 or more types together.

The number average particle diameter of the resin particles is preferably, for example, from 0.1 μm to 2 μm, and more preferably from 0.2 μm to 1 μm. When the number average particle diameter of the resin particles is less than 0.1 μm, the dispersibility of the resin particles in the coating film is very poor. On the other hand, when the number average particle diameter of the resin particles exceeds 2 μm, The resin particles are likely to fall off, and the original effect may not be exhibited.

  The content of the resin particles is, for example, preferably from 1% by weight to 50% by weight, more preferably from 1% by weight to 30% by weight, and more preferably from 1% by weight to 20% by weight with respect to the entire coating resin layer. Even more desirable is less than or equal to mass%. When the content of the resin particles is less than 1% by mass, the effect of the resin particles may not be exhibited. When the content exceeds 50% by mass, the resin particles easily fall off and stable chargeability cannot be obtained. There is a case.

  As conductive particles, metal particles such as gold, silver and copper, carbon black particles, semiconductive oxide particles such as titanium oxide and zinc oxide, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate Examples thereof include particles whose surface such as powder is covered with tin oxide, carbon black, metal or the like. These may be used individually by 1 type and may use 2 or more types together.

  Among these, carbon black particles are desirable from the viewpoints of production stability, cost, conductivity, and the like. The type of carbon black is not particularly limited, but carbon black having a DBP oil absorption of 50 ml / 100 g or more and 250 ml / 100 g or less is desirable because of excellent production stability.

  The volume average particle diameter of the conductive particles is preferably 0.5 μm or less, more preferably 0.05 μm or more and 0.5 μm or less, and still more preferably 0.05 μm or more and 0.35 μm or less. When the volume average particle size is larger than 0.5 μm, the conductive particles are likely to fall off the coating resin layer, and there is a possibility that stable chargeability cannot be obtained.

The volume electrical resistance of the conductive particles is preferably from 10 ¹ Ω · cm to 10 ¹¹ Ω · cm, and more preferably from 10 ³ Ω · cm to 10 ⁹ Ω · cm.

  The content of the conductive particles is preferably, for example, from 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the coating resin, and more preferably from 3 parts by mass to 20 parts by mass.

[Method for producing resin-coated carrier]
As a method for forming a coating film on the surface of the core material, an immersion method in which the core material is immersed in a coating film forming liquid containing a coating resin, a spray method in which the coating film forming liquid is sprayed on the surface of the core material, Examples thereof include a kneader coater method in which a core material is mixed with a coating film forming solution in a state of being suspended by flowing air and the solvent is removed. Among these, the kneader coater method is desirable.

  The solvent used in the coating film forming solution is not particularly limited as long as it can dissolve only the coating resin, and can be selected from known solvents such as toluene, Aromatic hydrocarbons such as xylene, ketones such as acetone and methyl ethyl ketone, and ethers such as tetrahydrofuran and dioxane.

  The average film thickness of the resin film is preferably, for example, 0.1 μm or more and 10 μm or less, and more preferably in the range of 0.5 μm or more and 3 μm or less from the viewpoint of expressing a stable volume electric resistance of the carrier over time.

―Resin dispersion type carrier―
As the matrix resin, the same resin as the carrier coating resin can be used.
Examples of the conductive material include metals (for example, gold, silver, copper, etc.), carbon black, titanium oxide, zinc oxide, barium sulfide, aluminum borate, potassium titanate, tin oxide, carbon black, and the like. However, it is not limited to these.

―Physical properties of the carrier―
The volume average particle diameter of the carrier is preferably 15 μm or more and 50 μm or less, and more preferably 25 μm or more and 40 μm or less. When the volume average particle diameter of the carrier is less than 15 μm, carrier contamination may occur. When the volume average particle diameter of the carrier is larger than 50 μm, toner deterioration due to stirring may become remarkable.

The volume electrical resistance of the carrier is 10 ⁶ Ω · cm or more and 10 ^{14 in} the range of 10 ³ V / cm to 10 ⁴ V / cm or less corresponding to the upper and lower limits of a normal development contrast potential in order to achieve high image quality. It is desirable that it is below Ω · cm. When the volume electric resistance of the carrier is less than 10 ⁶ Ω · cm, the reproducibility of the thin line is poor, and toner fogging on the background due to the injection of electric charge is likely to occur. On the other hand, if the volume electrical resistance of the carrier is larger than 10 ¹⁴ Ω · cm, reproduction of black solid and halftone becomes worse. In addition, the amount of carriers transferred to the photoconductor increases, and the photoconductor is easily damaged.

(Developer)
The mixing ratio (mass ratio) of the toner and the carrier in the developer containing the carrier is preferably in the range of toner: carrier = 1: 100 to 30: 100, more preferably in the range of 3: 100 to 20: 100. desirable.

  The developer desirably has an absolute value of the charge amount of 20 μC / g or more and 50 μC / g or less when the toner concentration (toner / carrier ratio) is 8 mass% and the charge generation environment is 25 ° C. and 50 RH%. More preferably, it is 25 μC / g or more and 45 μC / g or less, and further preferably 27 μC / g or more and 40 μC / g or less. When the absolute value of the charge amount is less than 20 μC / g, background fogging, image blanking, carrier scattering, and the like may occur. On the other hand, if it exceeds 50 μC / g, the image density may be lowered due to poor development. This amount of charge can be appropriately adjusted depending on, for example, the amount of the carrier coating resin, the amount of crosslinked melamine resin particles, the amount of fluorine in the coating resin, and the like.

  The developer can be produced by mixing the above-mentioned specific carrier and specific toner, but this production method is not particularly limited, and is appropriately performed according to a conventionally known method.

<Electrostatic charge image developer cartridge, image forming apparatus, and process cartridge>
Next, a developer cartridge for developing an electrostatic charge image in this embodiment (hereinafter sometimes simply referred to as “cartridge”) will be described. The cartridge is detached from the image forming apparatus and stores at least a developer to be supplied to a developing unit provided in the image forming apparatus, and the developer is the developer of the present embodiment described above. And

  Accordingly, in the image forming apparatus having a configuration in which the cartridge is detachable, by using the cartridge of the present embodiment in which the developer of the present embodiment is accommodated, the fixing member can be used to form an image with a small front end margin of the recording medium. The image peelability is good, a high gloss image is formed, and the offset resistance is good.

  The image forming apparatus according to the present exemplary embodiment includes an electrostatic latent image holding member, a charging unit that charges the surface of the electrostatic latent image holding member, and an electrostatic that forms an electrostatic latent image on the surface of the electrostatic latent image holding member. A latent image forming unit; a developing unit that develops the electrostatic latent image into a toner image using a developer; a transfer unit that transfers the toner image formed on the surface of the electrostatic latent image holding member to the surface of the recording medium; And a fixing unit that fixes the toner image transferred to the toner image, and the developer is the developer for developing an electrostatic image according to the exemplary embodiment.

  Therefore, by using the image forming apparatus of the present embodiment using the developer of the present embodiment, the image peelability from the fixing member is good even in the formation of an image with a small front end margin of the recording medium, and high glossiness is achieved. An image is formed and the offset resistance is good.

  Note that the image forming apparatus may include at least the electrostatic latent image holding member, the charging unit, the electrostatic latent image forming unit, the developing unit, the transfer unit, and the fixing unit as described above. Although there is no particular limitation, a cleaning unit, a charge removal unit, and the like may be included as necessary.

  The fixing unit includes a first fixing member and a second fixing member that comes into contact with the first fixing member, and a contact width at a contact portion between the first fixing member and the second fixing member is increased. What is 6 mm or more and 7 mm or less is desirable.

  Here, the contact width refers to the length along the recording medium traveling direction of the region where the first fixing member and the second fixing member are in contact with each other.

  Since the image forming apparatus according to the present embodiment uses the developer according to the present embodiment as described above, the fixing time can be shortened by setting the contact width within the above range. Therefore, even when the fixing means having the above-described configuration is used, the peelability of the image having a small front end margin of the recording medium from the fixing member is good, a high-gloss image is formed, and the offset resistance is good. . Therefore, by shortening the fixing time using the fixing unit having the above-described configuration, there is an advantage that image formation is performed at high speed and energy is saved.

  The process cartridge in the present embodiment stores the developer of the present embodiment, is detached from the image forming apparatus, includes a developing unit, and is selected from an electrostatic latent image holding member, a charging unit, and a cleaning unit. It is characterized by comprising at least one kind. In addition, the process cartridge may include other members such as a charge removing unit as necessary.

  Therefore, in the image forming apparatus having a configuration in which the process cartridge is detached, the image from the fixing member can be formed even in the formation of an image with a small front end margin of the recording medium by using the process cartridge containing the developer of the present embodiment. The peelability is good, a high gloss image is formed, and the offset resistance is good.

  Hereinafter, the cartridge, the image forming apparatus, and the process cartridge according to the present embodiment will be specifically described with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to a preferred embodiment. The image forming apparatus shown in FIG. 1 includes a cartridge.

An image forming apparatus 10 shown in FIG. 1 includes an electrostatic latent image holding body 12, a charging unit 14, an electrostatic latent image forming unit 16, a developing unit 18, a transfer unit 20, a cleaning unit 22, a neutralizing unit 24, a fixing unit 26, A cartridge 28 is provided.
The developer stored in the developing unit 18 and the cartridge 28 is the developer of this embodiment.

  For convenience, FIG. 1 illustrates only a configuration including one developing unit 18 and one cartridge 28 each containing a developer according to the present embodiment. However, for example, in the case of a color image forming apparatus, the image forming apparatus includes It is also possible to adopt a configuration including a corresponding number of developing means 18 and cartridges 28.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which a cartridge 28 is attached and detached. The cartridge 28 is connected to the developing means 18 through a developer supply pipe 30. Therefore, when performing image formation, the developer of the present invention stored in the cartridge 28 is supplied to the developing means 18 through the developer supply pipe 30, so that the developer of the present invention is applied over a long period of time. The used image can be formed. Further, when the amount of developer stored in the cartridge 28 is reduced, the cartridge 28 can be replaced.

  Around the electrostatic latent image holding body 12, charging means 14 for charging the surface of the electrostatic latent image holding body 12 in order along the rotational direction (arrow A direction) of the electrostatic latent image holding body 12, and image information Accordingly, an electrostatic latent image forming means 16 for forming an electrostatic latent image on the surface of the electrostatic latent image holding body 12, a developing means 18 for supplying the developer of the present invention to the formed electrostatic latent image, an electrostatic latent image The drum-shaped transfer means 20 that contacts the surface of the holding body 12 and can be driven to rotate in the direction of arrow B as the electrostatic latent image holding body 12 rotates in the direction of arrow A, contacts the surface of the electrostatic latent image holding body 12. There are disposed a cleaning unit 22 for performing static neutralization and a neutralizing unit 24 for neutralizing the surface of the electrostatic latent image holding body 12.

  A recording medium 50 transported in the direction of arrow C by a transport unit (not shown) from the opposite side to the direction of arrow C can be inserted between the electrostatic latent image holding body 12 and the transfer unit 20. A fixing unit 26 incorporating a heating source (not shown) is disposed on the electrostatic latent image holding body 12 in the direction of arrow C, and the fixing unit 26 is provided with a contact portion 32. Further, the recording medium 50 that has passed between the electrostatic latent image holder 12 and the transfer means 20 can be inserted through the contact portion 32 in the direction of arrow C.

As the electrostatic latent image holding member 12, for example, a photosensitive member or a dielectric recording member can be used.
As the photoreceptor, for example, a photoreceptor having a single layer structure or a photoreceptor having a multilayer structure can be used. As the material of the photoconductor, an inorganic photoconductor such as selenium or amorphous silicon, an organic photoconductor, or the like can be considered.

  Examples of the charging means 14 include a contact charging device using a conductive or semiconductive roller, brush, film, rubber blade, or the like, a non-contact charging device such as corotron charging or scorotron charging using corona discharge, and the like. Any known means can be used.

As the electrostatic latent image forming means 16, any conventionally known means capable of forming a signal capable of forming a toner image at a desired position on the surface of the recording medium can be used in addition to the exposure means.
As the exposure means, for example, a conventionally known exposure means such as a combination of a semiconductor laser and a scanning device, a laser scanning writing device constituted by an optical system, or an LED head can be used. In order to realize a desirable mode of producing a uniform and high-resolution exposure image, it is desirable to use a laser scanning writing device or an LED head.

  Specifically, as the transfer unit 20, for example, a conductive or semiconductive roller, brush, film, rubber blade, or the like to which a voltage is applied is used. The charged toner is obtained by corona charging the back surface of the recording medium 50 with a means for generating an electric field and transferring a toner image formed of charged toner particles, a corotron charger using a corona discharge, a scorotron charger, or the like. Conventionally known means such as a means for transferring a toner image formed with these particles can be used.

  A secondary transfer unit can also be used as the transfer unit 20. That is, although not shown, the secondary transfer unit is a unit that transfers the toner image to the intermediate transfer member and then secondary-transfers the toner image from the intermediate transfer member to the recording medium 50.

  Examples of the cleaning unit 22 include a cleaning blade and a cleaning brush. In the present embodiment, blade cleaning means using a cleaning blade is employed as the cleaning means 22.

  Examples of the charge eliminating unit 24 include a tungsten lamp and an LED.

As the fixing unit 26, for example, a known contact-type heat fixing device can be used.
Specifically, for example, a heating roll having a rubber elastic layer on the core metal and optionally having a surface layer of the fixing member, and a rubber elastic layer on the core metal, and if necessary, a fixing member A heat roll fixing device including a pressure roll having a surface layer, or a fixing device in which the combination of the roll and the roll is replaced with a combination of a roll and a belt, or a combination of the belt and the belt can be used.

  Hereinafter, the fixing unit 26 of this embodiment using a heating roll and a pressure belt will be described in detail with reference to the drawings.

FIG. 2 is a schematic cross-sectional view showing the fixing unit of the present embodiment.
As shown in FIG. 2, the fixing unit 26 according to the present embodiment contacts the heating roll 40 (first fixing member) that rotates in one direction (the direction of arrow E in FIG. 2) and the peripheral surface of the heating roll 40. An endless pressure belt 38 (second fixing member) that contacts at the portion 32 and rotates in one direction (the direction of arrow D).

  On the inner peripheral side of the pressure belt 38, a pressing member 44 that forms a contact portion with the heating roll 40, and a belt traveling guide 42 disposed on the opposite side of the contact portion between the pressure belt 38 and the heating roll 40, It is equipped with. The belt traveling guide 42 is fixed to the holder 44 </ b> C of the pressing member 44.

  The heating roll 40 is configured by sequentially forming an elastic layer 40B and a release layer 40C (surface release layer) on a core 40A (base material) having a heating source 46 (heating means) inside.

  As the core 40A, it is preferable to use a material having excellent heat resistance, high strength against deformation, and good thermal conductivity. Specifically, aluminum, iron, copper, etc. are mentioned, for example.

Examples of the material of the elastic layer 40B include heat-resistant rubber such as silicon rubber and fluorine rubber. The rubber hardness is preferably 60 or less.
When the fixing member has an elastic layer, it is advantageous in that the fixing member is deformed following the unevenness of the toner image on the transferred material, and the smoothness of the image surface after fixing can be improved.

  The thickness of the elastic layer 40B is preferably 0.1 mm to 3 mm. If the elastic layer is too thick, the heat capacity of the fixing member increases, so that it takes a long time to heat the fixing member and the energy consumption may increase. If the thickness of the elastic layer is too thin, the deformation of the fixing member cannot follow the unevenness of the toner image and unevenness may occur, and the elastic layer effective for peeling may not be obtained.

  As a material for the release layer 40C, a material having excellent releasability with respect to the toner is desirable for the purpose of preventing the toner from adhering. Specific examples of the material of the release layer 40C include silicon rubber, fluororubber, fluorolatex, and fluororesin. Among these, fluororesins are particularly excellent in terms of wear resistance.

  Examples of the fluororesin include soft fluororesins containing polytetrafluoroethylene such as perfluoroalkoxyethyl ether copolymer (PFA), vinylidene fluoride, and the like.

The release layer 40C may contain various additives depending on the purpose.
Specifically, for example, ceramic black particles such as carbon black, metal oxide, and SiC may be contained for the purpose of improving wear resistance and controlling the resistance value.

  Examples of the pressure belt 38 include a base material and a surface release layer provided on the outer peripheral surface of the base material.

  Examples of the base material include a polyimide film and a stainless steel belt.

  Examples of the material of the surface release layer include the same materials as those of the release layer 40C of the heating roll 40.

  Around the heating roll 40, a peeling member 52 for peeling the paper after fixing and a temperature sensor 54 for controlling the surface temperature of the heating roll 40 are provided. The peeling member 52 is provided on the downstream side in the conveyance direction (arrow F direction) of the recording medium 50 (recording medium) at the contact portion between the pressure belt 38 and the heating roll 40.

  The release member 52 includes a support portion 52A, one end of which is fixedly supported, and a release sheet 52B supported by the support member 52A. The release member 52B is disposed so that the tip of the release sheet 52B is close to or in contact with the heating roll 40.

  The pressing member 44 includes two pressing portions 44A and 44B having different hardnesses along the traveling direction (arrow F direction) of the recording medium 50. The pressure units 44A and 44B are supported by a holder 44C, and the heating roll 40 is provided from the inner peripheral surface of the pressure belt 38 via a low friction layer 44D such as a glass fiber sheet or a fluororesin sheet including Teflon (registered trademark). Pressing. Therefore, the pressurizing portions 44A and 44B may be selected as needed as long as they press the pressurizing belt 38 toward the heating roll 40. However, the pressurizing portions 44A and 44B are preferably configured to have heat resistance.

  For example, the pressure member 44A on the recording medium 50 entry side of the pressing member 44 is made of a rubber-like elastic member, the pressure part 44B on the discharge side of the recording medium 50 is made of a hard pressure applying member such as metal, and the contact part 32. Is set so that the recording medium 50 discharge side is higher than the recording medium 50 entry side. With this configuration, the peelability of the recording medium 50 (particularly thin recording paper) is improved as described above.

  Moreover, as for the contact width in the contact part 32, what is 6 mm or more and 7 mm or less is desirable as above-mentioned.

  As the low friction layer 44D, for example, a fluororesin sheet or the like can be used. As the fluororesin sheet, for example, PTFE, PFA, tetrafluoroethylene-hexafluoropropylene copolymer and the like can be used, but PTFE is desirable from the viewpoint of sliding frictional resistance. Further, the structure of the low friction layer 44D may be composed of a woven cloth single layer made of fluororesin fibers, and a porous fluororesin sheet may be laminated thereon.

  The recording medium 50 is not particularly limited, and conventionally known media such as plain paper and glossy paper can be used. A recording medium having a base material and an image receiving layer formed on the base material can also be used.

  Next, image formation using the image forming apparatus 10 will be described. First, as the electrostatic latent image holding body 12 rotates in the direction of arrow A, the surface of the electrostatic latent image holding body 12 is charged by the charging unit 14, and the electrostatic latent image holding body 12 surface is charged with the electrostatic latent image. An electrostatic latent image corresponding to the image information is formed by the image forming means 16, and the developing means 18 is formed on the surface of the electrostatic latent image holding body 12 on which the electrostatic latent image is formed according to the color information of the electrostatic latent image. A toner image is formed by supplying the developer of the present invention.

  Next, the toner image formed on the surface of the electrostatic latent image holding body 12 is brought into contact with the electrostatic latent image holding body 12 and the transfer unit 20 as the electrostatic latent image holding body 12 rotates in the arrow A direction. Move to the department. At this time, the recording medium 50 is inserted through the contact portion in the direction of arrow C by a paper conveyance roll (not shown), and the electrostatic latent image is transferred by the voltage applied between the electrostatic latent image holder 12 and the transfer means 20. The toner image formed on the surface of the image carrier 12 is transferred to the surface of the recording medium 50 at the contact portion.

  The toner remaining on the surface of the electrostatic latent image holding body 12 after the toner image is transferred to the transfer unit 20 is removed by the cleaning blade of the cleaning unit 22 and the charge is removed by the charge removing unit 24.

  The recording medium 50 having the toner image transferred onto the surface in this way is transported to the contact portion 32 of the fixing unit 26 and contacted by a built-in heating source (not shown) when passing through the contact portion 32. The surface of the section 32 is heated by the heated fixing means 26. At this time, an image is formed by fixing the toner image on the surface of the recording medium 50.

  Specifically, for example, simultaneously with the start of the toner image forming operation in the image forming apparatus 10 (of course, there may be a time lag. The same applies hereinafter), the heating roll 40 is moved by a motor (not shown). It is driven to rotate in the direction of arrow E at a peripheral speed of 200 mm / sec, for example.

  On the other hand, since the pressure belt 38 is in contact with the heating roll 40, the pressure belt 38 rotates by receiving a driving force from the heating roll 40 and is guided along the belt traveling guide 42.

  The recording medium 50 that holds the unfixed toner image T on the surface thereof is conveyed in the direction of arrow F by a conveying means (not shown), and an area of the contact portion 32 formed by contacting the pressure belt 38 and the heating roll 40. Is inserted.

  At this time, the recording medium 50 is inserted so that the surface of the recording medium 50 on which the unfixed toner image T is formed faces the surface of the heating roll 40. When the recording medium 50 passes through the contact portion 32, heat is applied to the recording medium 50 by the heating source 46 inside the heating roll 40, and pressure is also applied to the recording medium 50 at the same time, whereby the unfixed toner image T is formed. Then, it is fixed on the recording medium 50. After fixing, the recording medium 50 passes through the contact area, is peeled off from the heating roll 40 by the peeling member 52, and is discharged from the fixing device. In this way, the fixing process is performed.

  The time (contact time) for the recording medium 50 holding the unfixed toner image T to pass through the contact portion 32 formed by the pressure belt 38 and the heating roll 40 is preferably 15 ms or more and 30 ms or less. When the contact time is in the above range, there is an advantage that image formation is performed at high speed and energy is saved.

  If the contact time is smaller than the above range, it may be difficult to achieve both good fixing properties and prevention of paper wrinkles and curling, so it is necessary to raise the fixing temperature. Therefore, raising the fixing temperature may lead to waste of energy, deterioration of component durability, and temperature rise of the apparatus.

  FIG. 3 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to another preferred embodiment. The image forming apparatus shown in FIG. 3 includes a process cartridge.

  An image forming apparatus 200 shown in FIG. 3 includes a process cartridge 210 detachably disposed in an image forming apparatus main body (not shown), an electrostatic latent image forming unit 216, a transfer unit 220, and a fixing unit 226. It has.

  The process cartridge 210 has an electrostatic latent image holding body 212 in a casing 211 provided with an opening 211A for forming an electrostatic latent image, and a charging unit 214, a developing unit 218, and a cleaning unit 222 around the electrostatic latent image holding member 212. These are combined and integrated by mounting rails (not shown). Note that the process cartridge 210 is not limited to this, and it is only necessary to include the developing unit 218 and at least one selected from the group consisting of the electrostatic latent image holding member 212, the charging unit 214, and the cleaning unit 222.

  On the other hand, the electrostatic latent image forming unit 216 is disposed at a position where an electrostatic latent image can be formed on the electrostatic latent image holding body 212 from the opening 211A of the casing 211 of the process cartridge 210. The transfer unit 220 is disposed at a position facing the electrostatic latent image holder 212.

  The individual details of the electrostatic latent image holding member 212, the charging unit 214, the electrostatic latent image forming unit 216, the developing unit 218, the transfer unit 220, the cleaning unit 222, the fixing unit 226, and the recording medium 250 are illustrated in FIG. The same as the electrostatic latent image holding body 12, the charging unit 14, the electrostatic latent image forming unit 16, the developing unit 18, the transfer unit 20, the cleaning unit 22, the fixing unit 26, and the recording medium 50 in the image forming apparatus 10 of FIG. .

  The image formation using the image forming apparatus 200 of FIG. 3 is the same as the image formation using the image forming apparatus 10 of FIG.

  Since the image forming apparatus, the toner cartridge, and the process cartridge of the present embodiment use the developer of the present embodiment including the toner of the present embodiment, the image forming apparatus, the toner cartridge, and the process cartridge can be fixed even in the formation of an image with a small front margin on the recording medium. The image peelability from the member is good, a high gloss image is formed, and the offset resistance is good.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In the examples, “parts” and “%” mean “parts by mass” and “% by mass” unless otherwise specified.

<Measurement method>
―Measurement method of aluminum element content―
The content of the aluminum element with respect to the entire toner can be obtained by quantitative analysis of the fluorescent X-ray intensity. Specifically, for example, 200 mg of a mixture of polyester resin and aluminum sulfate having a known concentration is first weighed as a pellet sample using an IR tablet molding machine having a diameter of 13 mm, and the fluorescent X-ray intensity of this pellet sample is measured. Measurement was performed to determine the peak intensity corresponding to the aluminum element. Similarly, measurements were performed on samples in which the amount of aluminum sulfate added was changed, a calibration curve was created from these results, and the content of aluminum element in the actual measurement sample was quantified from the calibration curve.

―Measurement method of content of tin element―
The content of tin element with respect to the entire toner can be determined by quantitative analysis of the fluorescent X-ray intensity, as in the case of the aluminum element. Specifically, for example, a pellet sample was first prepared from a 200 mg mixture of a polyester resin having a known concentration and dibutyltin oxide using an IR tablet molding machine having a diameter of 13 mm, and the mass was precisely weighed. And the fluorescent X ray intensity measurement of this pellet sample was performed, and the peak intensity corresponding to a tin element was calculated | required. Similarly, measurements were performed on samples in which the addition amount of dibutyltin oxide was changed, a calibration curve was created from these results, and the content of tin element in the actual measurement sample was quantified from the calibration curve.

Here, it is necessary to use a polyester resin that does not use a polymerization catalyst or a resin that does not use a tin compound as a polymerization catalyst, when preparing a calibration curve sample. This is because the amount of catalyst remaining in the resin affects the quantitativeness.
In the method for measuring the content of tin element described above, the method using dibutyltin oxide has been described. However, for example, tin dioctanoate may be used instead of dibutyltin oxide.

-Measurement method of resin molecular weight and molecular weight distribution-
The molecular weight and molecular weight distribution of the resin can be measured by a known method, but are generally measured by gel permeation chromatography (hereinafter abbreviated as “GPC”).
Specifically, the molecular weight and molecular weight distribution of the resin were measured under the following conditions. As a GPC device, Tosoh Corporation HLC-8120GPC, SC-8020 device is used, TSK gei, Super HM-H (6.0 mm ID × 15 cm × 2) is used as a column, and the chromatograph manufactured by Wako Pure Chemical Industries, Ltd. is used as an eluent. THF (tetrahydrofuran) was used. As experimental conditions, the sample concentration was 0.5%, and the flow rate was 0.6 ml / min. Sample injection volume 10 μl, measurement temperature 40 ° C., calibration curve is A-500, F-1, F-10, F-80, F-380, A-2500, F-4, F-40, F-128, Made from 10 samples of F-700. The data collection interval in sample analysis was 300 ms.

  Here, when measuring the molecular weight of the crystalline resin, since the solubility of the crystalline resin in THF was poor, the crystalline resin was dissolved by heating in a 70 ° C. hot water bath.

-Measurement method of acid value-
2 g of a sample was weighed and dissolved in 160 ml of acetone-toluene, or a sample with insufficient solubility was heated and dissolved, and then measured by the potentiometric titration method of JIS K0070-1992.

―Measurement method of softening point of resin―
The softening point of the resin was as follows: sample amount: 1.05 g, preheating: 300 sec at 65 ° C., plunger pressure: 0.980665 MPa, die size: diameter 1 mm, using a flow tester (Shimadzu Corporation: CFT-500C) Temperature rate: refers to an intermediate temperature between the melting start temperature and the melting end temperature measured under the condition of 1.0 ° C./min.

―Measurement method of loss modulus of resin―
Here, the loss elastic modulus of the resin is measured as follows. The measuring device is a rheometer manufactured by Rheometrics, trade name “RDA II” (RHIOS system ver. 4.3), the measuring plate is a parallel plate with a diameter of 8 mm, the zero point adjustment temperature is 90 ° C., the plate At a gap of 3.5 mm, a heating rate of 1 ° C. per minute, an initial measurement strain of 0.01%, and a measurement start temperature of 30 ° C., the strain is adjusted so that the detected torque becomes about 10 gcm as the temperature rises. % And the measurement was completed when the detected torque was below the lower limit of the guaranteed measurement value.

-Method of measuring the dispersion rate of silica particles-
After embedding the toner with an epoxy embedding agent, the slice was cut to a thickness of 0.1 μm with a diamond knife, and the slice was cut with an acceleration voltage of 30 KV and a magnification of 10,000 with JEOL JSM6700F. Observed under conditions.

100 sections were randomly selected from the cut surface of the section, and the analysis spot was set to 1 μm ² using JED Corporation JED2300F attached to the apparatus (JEOL Corporation JSM6700F). X-ray measurement was performed.

Among the 100 regions, the intensity ratio (I _Si / I _C ) of the fluorescent X-ray intensity (I _Si ) corresponding to the silicon element to the fluorescent X-ray intensity (I _C ) corresponding to the carbon element is 0. The ratio of the region of 07 or more and 0.12 or less was determined and was defined as “dispersion rate of silica particles”.

-Measurement method of volume average particle diameter of particles (when particle diameter of particles to be measured is less than 1μm)-
When the particle diameter of the particles to be measured is less than 1 μm, the volume average particle diameter of the particles is measured using a laser diffraction particle size distribution measuring device (LA-700: manufactured by Horiba, Ltd.).

  As a measuring method, the sample in the state of dispersion is adjusted so as to have a solid content of 2 g, and ion exchange water is added thereto to make 40 ml. This is put into the cell until an appropriate concentration is reached, waits for 2 minutes, and the concentration is measured when the concentration in the cell becomes almost stable.

  For the measured particle size distribution, a cumulative distribution is drawn from the smaller diameter side with respect to the divided particle size range (channel), and the particle size that is 50% cumulative in volume is defined as the volume average particle size.

  When measuring powders such as external additives, 2 g of a measurement sample is added to 50 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzene sulfonate, and 2 with an ultrasonic disperser (1,000 Hz). A sample is prepared by dispersing for a minute, and measurement is performed in the same manner as in the above-mentioned dispersion.

-Measurement method of volume average particle diameter of toner-
The volume average particle size of the toner was measured using a Coulter Multisizer II type (manufactured by Beckman Coulter, Inc.) with an aperture diameter of 50 μm. At this time, the measurement is performed after the toner is dispersed in an electrolyte aqueous solution (Isoton aqueous solution) and dispersed by ultrasonic waves for 30 seconds or more.

  As a measuring method, 0.5 to 50 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate as a dispersant, and this is added to 100 to 150 ml of the electrolytic solution. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment for 1 minute with an ultrasonic disperser, and the particle size distribution of the particles is measured. The number of particles to be measured is 50,000.

  For the measured particle size distribution, a cumulative distribution is drawn from the smaller diameter side with respect to the divided particle size range (channel), and the particle size at which 50% is accumulated is defined as the volume average particle size.

<Example α>
(Adjustment of each dispersion)
-Adjustment of crystalline polyester resin 1-
-Dimethyl dodecanedioate 132 parts by mass-79 parts by mass of 1,9-nonanediol-Titanium tetrabutoxide (catalyst) 0.5 parts by mass

After putting the above components into a heat-dried three-necked flask, the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and the mixture was stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring.
Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was cooled with air, the reaction was stopped, and “crystalline polyester resin 1” was synthesized.
In the molecular weight measurement (polystyrene conversion) by gel permeation chromatography, the obtained “crystalline polyester resin 1” had a weight average molecular weight (Mw) of 23,000 and a melting temperature of 74 ° C.

-Preparation of amorphous polyester resin 1 to amorphous polyester resin 6-
The monomer listed in Table 1 was charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column, and the temperature was raised to 190 ° C. over 1 hour. After confirming uniform stirring, the catalysts listed in Table 1 were similarly charged.
Furthermore, while distilling off the generated water, the temperature was raised from the same temperature to 6O 0 C to 240 ° C, and the dehydration condensation reaction was continued at 240 ° C for another 3 hours. Crystalline polyester resin 6 "was obtained. Table 2 shows the acid value, weight average molecular weight (Mw), and glass transition temperature of each amorphous polyester resin.

-Preparation of crystalline resin particle dispersion 1-
80 parts of crystalline polyester resin 1 and 720 parts of ion-exchanged water were each placed in a stainless beaker, placed in a warm bath, and heated to 98 ° C. When the crystalline polyester resin was melted, it was stirred at 7000 rpm using a homogenizer (manufactured by IKA, Ultra Turrax T50). Subsequently, the emulsion was dispersed while dropping 1.8 parts of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK, solid content: 20% by mass) to obtain a crystalline resin particle dispersion (solid content: 10% by mass) was obtained. The volume average particle size of the resin particles in the obtained crystalline resin particle dispersion was 180 nm.

-Preparation of amorphous resin particle dispersion 1-
-Amorphous polyester resin 1 100 parts by mass-Ethyl acetate 70 parts by mass-Isopropyl alcohol 15 parts by mass

  A mixed solvent of the ethyl acetate and the isopropyl alcohol was added to a 5 L separable flask, and the resin was gradually added thereto, and the mixture was stirred with a three-one motor and completely dissolved to obtain an oil phase.

  To this stirred oil phase, a 10% by mass aqueous ammonia solution is gradually added dropwise with a dropper so that the total amount becomes 3 parts by mass, and further 230 parts by mass of ion-exchanged water is gradually added dropwise at a rate of 10 ml / min. Phase-emulsification was performed, and the solvent was removed while the pressure was reduced with an evaporator to obtain “amorphous resin particle dispersion 1” containing “amorphous polyester resin 1”. The volume average particle diameter of the resin particles dispersed in this dispersion was 182 nm. The resin particle concentration of the dispersion was adjusted to 20% by mass with ion exchange water.

-Preparation of amorphous resin particle dispersion 2 to amorphous resin particle dispersion 6-
Instead of “amorphous polyester resin 1”, “amorphous polyester resin 2” to “amorphous polyester resin 6” were used in the same manner as “amorphous resin particle dispersion 1”, respectively. “Amorphous resin particle dispersion 6” was obtained from “Amorphous resin particle dispersion 2”. Table 3 shows the volume average particle diameter of the obtained amorphous resin particle dispersion. The resin particle concentration of these dispersions was adjusted with ion exchange water to 20% by mass.

-Preparation of colorant particle dispersion 1-
Cyan pigment (copper phthalocyanine B15: 3, manufactured by Dainichi Seika) 45 parts by mass Nonionic surfactant (Nonipol 400, manufactured by Sanyo Chemical Co., Ltd.) 5 parts by weight Ion-exchanged water 200 parts by weight

  The above components were mixed and dissolved, and dispersed with a homogenizer (IKA Ultra Tarrax) for 10 minutes to obtain “Colorant Particle Dispersion 1” having a volume average particle size of 168 nm and a solid content of 22.0 parts by mass.

-Preparation of release agent particle dispersion 1-
・ Paraffin wax HNP9
(Releasing agent, melting temperature 72 ° C., acid value 0 mg KOH / g, manufactured by Nippon Seiki Co., Ltd.) 45 parts by mass, anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts by mass, ion-exchanged water 200 parts by mass

  The above components were heated to 95 ° C. and sufficiently dispersed with IKA Ultra Tarrax T50, and then dispersed with a pressure discharge type gorin homogenizer. The volume average particle size was 205 nm and the solid content was 20 parts by mass. Molding agent particle dispersion 1 ”was obtained.

-Preparation of release agent particle dispersion 2 to release agent particle dispersion 4-
Except for the types and addition amounts of the release agents used as shown in Table 4, “release agent particle dispersion 2” to “release agent particle dispersion 4” in the same manner as “release agent particle dispersion 1”. "
Table 4 also shows the melting temperature and acid value of the used release agent, and the volume average particle size and solid content (addition amount) of the release agent particles in the obtained dispersion.

(Production of toner)
-Example 1 (Production of Toner 1)-
-Crystalline resin particle dispersion 1 50 parts by mass-Amorphous resin particle dispersion 2 171 parts by mass-Amorphous resin particle dispersion 3 57 parts by mass-Colorant particle dispersion 1 25 parts by mass-Release agent particles Dispersion 1 45 parts by mass

  The above components were sufficiently mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50). Next, 1.05 parts by mass of a 10% by mass polyaluminum chloride aqueous solution as an aluminum-based flocculant was added thereto, and the dispersion operation was continued with an Ultratalx T50.

Subsequently, a stirrer and a mantle heater were installed, and the temperature was raised to 47 ° C. at 0.5 ° C./min and maintained at 47 ° C. for 15 minutes while adjusting the rotation speed of the stirrer so that the slurry was sufficiently stirred. Thereafter, the particle size was measured with a Coulter Multisizer II (aperture diameter: 50 μm, manufactured by Beckman Coulter, Inc.) every 10 minutes while raising the temperature at 0.05 ° C./min. When the thickness reached 0 μm, 105 parts by mass (additional resin) of amorphous resin particle dispersion 2 and 38 parts by mass (additional resin) of amorphous resin particle dispersion 3 were added over 3 minutes. After holding for 30 minutes, the pH was adjusted to 9.0 using a 5% aqueous sodium hydroxide solution. Thereafter, while adjusting the pH to 9.0 every 5 ° C., the temperature was raised to 96 ° C. at a temperature rising rate of 1 ° C./min and maintained at 96 ° C. When the particle shape and surface properties were observed with an optical microscope and a scanning electron microscope (FE-SEM) every 30 minutes, the particles were spheroidized after 5 hours. Solidified.
Thereafter, the reaction product was filtered, sufficiently washed with ion-exchanged water, and then dried using a vacuum dryer, whereby toner particles 1 having a volume average particle diameter of 6.0 μm were obtained.
To 100 parts by mass of the obtained toner particles, 1 part of colloidal silica (manufactured by Nippon Aerosil Co., Ltd., R972) is added and mixed and blended using a Henschel mixer to obtain toner 1 to which silica is externally added.

  Table 5 shows the aluminum element content and the tin element content with respect to the whole toner 1 and the volume average particle diameter of the toner 1.

-Example 2 to Example 5 (Preparation of toner 2 to toner 5)-
The toner 2 to the toner 5 were prepared in the same manner as in the toner 1 except that the types of the amorphous resin particle dispersion and the release agent particle dispersion used, the type of the aluminum-based flocculant, and the amount added were as shown in Table 5. Obtained.
Table 5 also shows the content of aluminum element, the content of tin element, and the volume average particle diameter in the obtained toner.

-Comparative Example 1 to Comparative Example 4 (Production of Toner 6 and Toner 9)-
The toner 6 to the toner 9 were prepared in the same manner as in the toner 1 except that the types of the amorphous resin particle dispersion and the release agent particle dispersion used, the type of the aluminum-based flocculant, and the amount added were as shown in Table 5. Obtained.
Table 5 also shows the content of aluminum element, the content of tin element, and the volume average particle diameter in the obtained toner.

(Development of developer)
-Production of developer 1-
To a carbon dispersion obtained by mixing 1.25 parts of toluene with 0.10 parts of carbon black (trade name; VXC-72, manufactured by Cabot Corporation) and stirring and dispersing in a sand mill for 20 minutes, a trifunctional isocyanate 80% ethyl acetate solution ( Takenate D110N (manufactured by Takeda Pharmaceutical Company Limited), 1.25 parts of the coating agent resin solution mixed and stirred, and Mn—Mg—Sr ferrite particles (volume average particle size: 50 μm) were put into a kneader and mixed at 25 ° C. for 5 minutes. After stirring, the temperature was raised to 150 ° C. at normal pressure to distill off the solvent. After further 30 minutes of mixing and stirring, the heater was turned off and the temperature was lowered to 50 ° C. The obtained coated carrier was sieved with a 75 μm mesh to prepare a carrier.
The obtained carrier and “toner 1” were mixed and prepared so that the toner concentration was 8% by mass, and “developer 1” was produced.

-Preparation of developer 2 to developer 9-
“Developer 2” to “Developer 9” were prepared in the same manner as “Developer 1” except that “Toner 2” to “Toner 9” were used instead of “Toner 1”.

(Image formation)
The prepared developer was set in a developing device of a color copying machine “DocuCenter-II C4300” manufactured by Fuji Xerox Co., Ltd. modified so that the roll temperature of the fixing device could be changed, and 10,000 images were continuously formed.

  The output image and paper are as follows.

-Evaluation of image glossiness and evaluation of gloss unevenness Output image: Solid image of 50 mm x 50 mm Image toner amount: 5.0 g / m ²
Paper: Mirror coat platinum (basis weight: 256 gsm, manufactured by Oji Paper Co., Ltd.)

・ Evaluation of high temperature offset generation temperature Output image: Solid image of 50 mm × 50 mm Image toner amount: 5.0 g / m ²
Paper: ST paper (A3 longitudinal, basis weight: 52.3 gsm, manufactured by Fuji Xerox Co., Ltd.)

・ Evaluation of the number of wraps generated Output image: Full solid image with a 1 mm front margin Image toner amount: 5.0 g / m ²
Paper: ST paper (A3 longitudinal, basis weight: 52.3 gsm, manufactured by Fuji Xerox Co., Ltd.)

The fixing of the image was performed by changing the sheet conveying speed of the fixing device to 165 mm per second and appropriately changing the temperature of the fixing device (fixing temperature) from 110 ° C. to 200 ° C.
The contact width at the contact portion of the fixing device is 6.0 mm, and the passage time of the paper at the contact portion of the fixing device is 36.4 ms.

(Evaluation)
―Evaluation of image glossiness―
The fixing temperature is set to 180 ° C., and 10,000 images are continuously formed. The glossiness (gross value) of the fixed image obtained on the first image and the fixed image obtained on the 10,000th image, Using a gloss meter “micro-TRI-gloss” manufactured by BYK-Gardner, the measurement was performed under the condition where the incident light angle to the sample was 60 degrees. The results are shown in Table 6. If the gloss value is 60% or more, there is no practical problem.

―Evaluation of gloss unevenness―
The fixing temperature is set at 180 ° C., and 10,000 images are continuously formed. The glossiness unevenness of the fixed image obtained on the first image and the fixed image obtained on the 10,000th image is visually evaluated. Went. The results are shown in Table 6. The evaluation criteria are as follows, and there is no practical problem if it is G1 to G3.

G1: No gloss unevenness, very good G2: Little gloss unevenness, good G3: Slight gloss unevenness is acceptable, but acceptable G4: There are gloss unevenness and image quality problems G5: Gloss unevenness is remarkable , Serious image quality problem

―Evaluation of high temperature offset generation temperature―
An image was formed by appropriately changing the fixing temperature from 110 ° C. to 200 ° C. by 5 ° C., and toner adhesion on the surface of the fixing member after image fixing was visually confirmed. The lowest temperature at which toner adhesion began to occur was defined as the high temperature offset generation temperature. If it is 190 degreeC or more, there is no problem practically. The results are shown in Table 6.

―Evaluation of the number of windings―
100 images were continuously formed with the fixing temperature set at 180 ° C., and the number of sheets in which the paper was wound around the fixing member was evaluated. There is no problem if it does not occur. The results are shown in Table 6.

<Example β>
(Dispersion adjustment)
-Preparation of silicon oxide particles 1-
Synthetic silica powder Aerosil 130 (Nihon Aerosil Co., Ltd.) in 4,000 ml (3120 parts by mass) of 2-propanol as a solvent in a reaction vessel equipped with a stirrer having a plurality of stirring blades, a reflux condenser, a thermometer, and a nitrogen introduction tube. Manufactured, average primary particle diameter 16 nm) 300 parts by mass of a slurry particle dispersion and 51.7 parts by mass of methyltrimethoxysilane (manufactured by Gerest) (0.38 mol) are added, and the mixed solution is Obtained.

  After replacing the inside of the reaction vessel with dry nitrogen gas, the temperature of the mixed solution was raised to 80 ° C. while stirring under a nitrogen gas stream. Thereafter, 50 ml of 0.1N hydrochloric acid was added dropwise as a catalyst, and the reaction was allowed to stir for 6 hours.

After the stirring reaction, the mixed solution was taken out, and the treated particles were separated by centrifugation, washed with ion-exchanged water, stirred and centrifuged for 5 times. Finally, the water was removed by freeze-drying to obtain “silicon oxide particles 1” treated with methyltrimethoxysilane.

Furthermore, the “silicon oxide particles 1” vacuum-dried at 100 ° C. for 1 hour was put into a 2% dimethylene glycol dimethyl ether solution of aluminum hydroxide, and the amount of hydrogen generated by the reaction of the following formula was measured. The amount of silanol groups was quantified to determine the hydrophobization rate. As a result, the surface hydrophobization rate of the “silicon oxide particles 1” was 55%.
Formula: nR—OH + LiAlH ₄ → LiAl (OR) _n H _4−n + nH ₂

-Preparation of resin silica particle dispersion 1-
-Amorphous polyester resin 2 90 parts by mass-Silicon oxide particles 1 10 parts by mass-Ethyl acetate 70 parts by mass-Isopropyl alcohol 15 parts by mass

  Into a 5 L separable flask, the mixed solvent of ethyl acetate and isopropyl alcohol is added, and silicon oxide particles 1 are added thereto. The resin is gradually added thereto, and the mixture is stirred with a three-one motor. The oil phase was obtained by dissolving.

  To this stirred oil phase, a 10% by mass aqueous ammonia solution is gradually added dropwise with a dropper so that the total amount becomes 3 parts by mass, and further 230 parts by mass of ion-exchanged water is gradually added dropwise at a rate of 10 ml / min. Phase-emulsification was carried out, and the solvent was removed while reducing the pressure with an evaporator to obtain “resin silica particle dispersion 1” containing “amorphous polyester resin 2” in which “silicon oxide particles 1” were dispersed. The volume average particle diameter of the resin particles dispersed in this dispersion was 150 nm. The resin particle concentration of the dispersion was adjusted to 20% by mass with ion exchange water.

-Preparation of resin silica particle dispersion 2-
“Resin silica particle dispersion 2” was the same as “Resin silica particle dispersion 1” except that the addition amount of amorphous polyester resin 2 was 95 parts by mass and the addition amount of silicon oxide particles 1 was 5 parts by mass. "

-Preparation of silicon oxide particle dispersion 1-
・ 45 parts by mass of silicon oxide particles 1 ・ 5 parts by mass of nonionic surfactant (Sanyo Kasei Co., Ltd., Nonipol 400) ・ 200 parts by mass of ion-exchanged water

  The above components were mixed and dissolved, and dispersed for 10 minutes with a homogenizer (manufactured by IKA, Ultra Tarra Ultra Tarrax) to obtain a silicon oxide particle dispersion 1 having a volume average particle size of 140 nm.

(Production of toner)
—Example β-1 (Production of Toner β-1) —
171 parts by mass of the resin silica particle dispersion 1 was used instead of the amorphous resin particle dispersion 2, and 113 parts by mass of the resin silica particle dispersion 1 was used instead of the amorphous resin particle dispersion 2 as an additional resin. Produced “Toner β-1” in the same manner as “Toner 1” of Example 1 in Example α described above.
Table 7 shows the content of aluminum element, the content of tin element, the addition amount of silicon oxide particles, the dispersion rate of silicon oxide particles, and the volume average particle diameter with respect to the entire “toner β-1”.

-Example β-2 (Preparation of toner β-2)-
Instead of amorphous resin particle dispersion 2, 171 parts by mass of resin silica particle dispersion 2 and 113 parts by mass of resin silica particle dispersion 1 instead of amorphous resin particle dispersion 2 as an additional resin were used. Produced “Toner β-2” in the same manner as “Toner 1” of Example 1 in Example α described above.
Table 7 shows the content of aluminum element, the content of tin element, the addition amount of silicon oxide particles, the dispersion rate of silicon oxide particles, and the volume average particle size with respect to the entire “toner β-2”.
—Example β-3 (Production of Toner β-3) —
Instead of the amorphous resin particle dispersion 2, 165 parts by mass of the amorphous resin particle dispersion 2 and 6 parts by mass of the silicon oxide particle dispersion 1 were used. In the same manner as “Toner 1”, “Toner β-3” was produced.
Table 7 shows the content of aluminum element, the content of tin element, the addition amount of silicon oxide particles, the dispersion rate of silicon oxide particles, and the volume average particle diameter with respect to the entire “toner β-3”.

(Development of developer)
-Preparation of developer β-3 from developer β-1-
“Developer β-1” to “Developer β-3” are the same as “Developer 1” in Example α except that toner β-1 to toner β-3 were used instead of toner 1. Was made.

(Image formation and evaluation)
Using the adjusted developer, image formation and evaluation were performed in the same manner as in Example α. The results are shown in Table 8.

  From the results shown in Tables 6 and 8, according to Examples 1 to 5 and Examples β-1 to β-3, the leading edge margin of the recording medium is larger than that of Comparative Examples 1 to 4. It can be seen that even in the formation of a small image, the image peelability from the fixing member is good, a highly glossy image is formed, and the offset resistance is good.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. 1 is a schematic configuration diagram illustrating an example of a fixing device according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Electrostatic latent image holding body 14 Charging means 16 Electrostatic latent image forming means 18 Developing means 20 Transfer means 26 Fixing means 28 Cartridge 32 Contact part 38 Pressure belt (fixing member)
40 Heating roll (fixing member)
50 recording medium 200 image forming apparatus 210 process cartridge 212 electrostatic latent image holder 214 charging means 216 electrostatic latent image forming means 218 developing means 220 transfer means 222 cleaning means 226 fixing means 250 recording medium

Claims (13)

Contains a crystalline polyester resin, an amorphous polyester resin, an aluminum element, a tin element, and a release agent,
The content of the aluminum element is 0.005% by mass or more and 0.060% by mass or less based on the whole toner,
The content of the tin element is 0.12% by mass or more and 0.72% by mass or less based on the whole toner,
The toner for developing an electrostatic charge image, wherein an acid value of the release agent is 0 mgKOH / g or more and 5.0 mgKOH / g or less.   The electrostatic image developing toner according to claim 1, further comprising silicon oxide particles, wherein a dispersion ratio of the silicon oxide particles is 80% or more and 100% or less.   The toner for developing an electrostatic charge image according to claim 2, wherein the addition amount of the silicon oxide particles is 1% by mass or more and 10% by mass or less based on the whole toner.   An electrostatic image developing developer comprising at least the electrostatic image developing toner according to claim 1. Contains a developer that is detached from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus;
The developer cartridge for developing an electrostatic charge image according to claim 4, wherein the developer is a developer for developing an electrostatic charge image. An electrostatic latent image carrier;
Charging means for charging the surface of the electrostatic latent image holding member;
Electrostatic latent image forming means for forming an electrostatic latent image on the surface of the electrostatic latent image holding member;
Developing means for developing the electrostatic latent image into a toner image with a developer;
Transfer means for transferring the toner image formed on the surface of the electrostatic latent image holding member to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the recording medium,
The image forming apparatus according to claim 4, wherein the developer is an electrostatic charge image developing developer. The fixing unit includes a first fixing member and a second fixing member in contact with the first fixing member,
The image forming apparatus according to claim 6, wherein a contact width at a contact portion between the first fixing member and the second fixing member is 6 mm or more and 7 mm or less. Development for developing the electrostatic latent image developing developer according to claim 4 and developing the electrostatic latent image formed on the surface of the electrostatic latent image holding body into a toner image by the electrostatic charge image developing developer. Means,
At least one selected from the group consisting of an electrostatic latent image holding body, a charging means for charging the electrostatic latent image holding body, and a toner removing means for removing toner remaining on the surface of the electrostatic latent image holding body And comprising
A process cartridge which is detachable from an image forming apparatus.   A recording medium holding a toner image formed with the electrostatic image developing toner according to claim 1 is in contact with a first fixing member and a second fixing member. A fixing method in which the toner image is fixed on the recording medium by passing through the contact portion of the fixing member while heating.   The fixing method according to claim 9, wherein a contact width at the contact portion is 6 mm or greater and 7 mm or less.   The fixing method according to claim 9 or 10, wherein a passing time for passing the recording medium holding the toner image while heating at the contact portion is 15 ms or more and 30 ms or less. An electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image holding member;
A developing step of developing the electrostatic latent image into a toner image with a developer;
A transfer step of transferring the toner image to the surface of the recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium to the surface of the recording medium;
Including
The image forming method according to claim 4, wherein the developer is an electrostatic charge developing developer. The image forming method according to claim 12, wherein the fixing step is a step of fixing the toner image on the recording medium by the fixing method according to any one of claims 9 to 11.

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