JP2015072359A - Toner, developer, image forming apparatus, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner that is excellent in fixability in low-temperature fixing, heat-resistant storage property, toner spent prevention, toner filming prevention, image quality after fixing, and prevention of adhesion of an image surface; a developer using the toner; an image forming apparatus; and an image forming method.SOLUTION: There is provided a toner containing at least a binder resin and capsules, where the capsules each have a core material including at least a plasticizer softening the binder resin and poorly water-soluble substance, and a shell material that is not softened by the plasticizer and is destroyed upon application of a pressure equal to or larger than a predetermined pressure; the plasticizer and poorly water-soluble substance have a melting point of higher than 60°C.

Description

  The present invention relates to a toner, a developer using the toner, an image forming apparatus, and an image forming method.

  An electrophotographic image forming apparatus visualizes a latent image formed electrically or magnetically with toner. For example, an electrostatic charge image (latent image) is formed on the photosensitive member, and then the latent image is developed with toner to form a toner image. The toner image is usually transferred onto a transfer medium (recording medium) such as paper and then fixed on the recording medium.

With the development of image forming technology, an apparatus capable of forming a higher-definition image has been developed, and in order to improve image quality, it is required to reduce the particle diameter of toner particles to about 4 to 6 μm.

On the other hand, in the fixing process of a toner image onto a recording medium, a heat fixing method such as a heating roller fixing method and a heating belt fixing method is widely used because of its energy efficiency.

In recent years, the demand for energy saving for image forming apparatuses from the market is increasing, and there is a demand for a toner capable of providing a high-quality image with excellent fixing property at a fixing temperature close to room temperature (hereinafter abbreviated as low-temperature fixing). .

However, the heat fixing methods alone such as the heating roller fixing method and the heating belt fixing method cannot satisfy these requirements, particularly energy saving.

In order to achieve low-temperature fixability of the toner, for example, there is a method of lowering the softening point of the binder resin.
However, if the softening point of the binder resin is low, the heat resistance of the toner is lowered, and there is a problem that so-called blocking occurs in which toner particles are fused with each other in a high temperature environment.
In the developing unit, there is a problem that the toner is fused and contaminated inside the developing unit and the carrier (toner spent problem), and a problem that the toner is easily filmed on the surface of the photosensitive member (toner filming problem). .

Further, regarding the image after fixing, for example, outside of the image forming apparatus, it is not unusual that the temperature is about 40 ° C. to 50 ° C. in an automobile in the summer, etc. There is a problem that surface sticking is likely to occur.
Therefore, it is difficult to achieve low-temperature fixing simply by lowering the softening point of the binder resin.

In Japanese Patent No. 5022308 of Patent Document 1, a solid plasticizer and a resin are mixed, and the resin is subjected to an elongation reaction to form a capsule containing the solid plasticizer, which is dispersed in a toner binder resin. Toner is disclosed.
However, this proposed technique is intended to improve the glossiness of the output image, not intended to achieve low-temperature fixing, and this technique cannot achieve low-temperature fixing.
In other words, the capsule has a large particle size, and with this technique, it is impossible to disperse the plasticizer in the toner particles with a minute diameter, and the plasticizer partially dissolves in the binder resin during the manufacturing process. As a result, toner filming and toner spent occur. Further, the plasticizer used has low compatibility with the binder resin, and does not sufficiently soften the toner during fixing.
In addition, if this technology is applied to produce a toner with good plasticization efficiency using a plasticizer that is highly compatible with the binder resin, the shell material of the capsules will melt together with the plasticizer. Is softened by the plasticizer or the plasticizer is eluted out of the toner, and the intended encapsulated toner cannot be obtained.

Many methods for producing small fine particles of 1 μm or less have been proposed. For example, Japanese Patent Application Laid-Open No. 2012-1117021 of Patent Document 2 does not relate to toner, but encapsulates pigments using a mini-emulsion polymerization method. Techniques to do this are disclosed.
The mini-emulsion polymerization method used in this technology is the production of oil-in-water emulsion and the addition of a poorly water-soluble substance such as hexadecane to the oil phase in advance. And fine particles of 1 μm or less are obtained.
However, even if this technology is applied to a plasticizer-encapsulated capsule that softens the binder resin, since the hexadecane is a liquid, the liquid is present in a part of the capsule, and the strength of the capsule is reduced. The capsule is broken by stirring in the developing machine, and toner spent and toner filming are likely to occur.

Japanese Patent Application Laid-Open No. 2011-73456 of Patent Document 3 and Japanese Patent Application Laid-Open No. 2008-56828 of Patent Document 4 are not related to toner, but for producing a capsule having a small particle diameter with a uniform particle diameter. In addition, those using oligomers or polymers have been proposed as poorly water-soluble substances that stabilize minute oil droplets in water. In any of these, since the molecular weight of the poorly water-soluble substance is large, the viscosity of the oil phase becomes remarkably high when mixed with the plasticizer, so that it is difficult to form fine oil droplets by a normal emulsification method.
In addition, in order to produce a plasticizer capsule having a particle size required by miniemulsion polymerization, the plasticizer must be further reduced in size and dispersed in monomer droplets that form a shell in water. It is virtually impossible to reduce the diameter of the agent.
Further, if the plasticizer and the monomer are dissolved, the plasticizer is eluted outside without obtaining a capsule having a core-shell structure.

Japanese Patent Application Laid-Open No. 2013-7996 of Patent Document 5 includes that a toner containing a capsule containing a solid plasticizer is contained in the toner particles, so that the plasticizer softens the binder resin during fixing and can be fixed at a lower temperature. Techniques to do this have been proposed. However, in order to quickly soften and fix the toner, the encapsulated plasticizer needs to be uniformly finely dispersed in the toner particles. For this purpose, the particle size of the capsule containing the plasticizer must be about 300 to 500 nm, which is smaller than that of the toner particles. In this proposed technique, a capsule having such a small particle size is produced. Is difficult.
On the other hand, when the capsule diameter is increased, the binder resin is softened only around the capsule inside the toner particles at the time of fixing, and the toner is not crushed uniformly and the image quality is deteriorated.
In addition, in order to disperse relatively large capsules in toner particles, the size of the toner particles themselves becomes large, and in recent years, a high-definition image is required. .

In addition, in the core solvation method, the addition of ethanol may cause the plasticizer to flow out of the capsule and the melting point may be lowered (poor solidification). In the spray drying method, complete coating is difficult.

In addition, since there is a heat source such as a fixing device in the developing unit, the temperature may rise to close to 60 ° C. Further, since the developer is stirred with a strong force for charging, the melting point of the plasticizer If it is low, the plasticizer melts and the capsule is destroyed, and the plasticizer exudes from the capsule and softens the binder resin, which may cause spent or filming.

As described above, the conventional technology enables low-temperature fixing at a temperature close to room temperature while maintaining toner hardness to such an extent that toner spent and toner filming do not occur in a developing device having a temperature close to 60 ° C. Thus, it has not been possible to satisfy both the conditions that the image after fixing has high quality and heat resistance.

Therefore, toner having excellent fixability in low-temperature fixing, heat-resistant storage, toner spent prevention, toner filming prevention and image quality after fixing, image surface sticking prevention, developer using the toner, container containing toner, At present, it is required to provide an image forming apparatus, an image forming method, and a process cartridge.

The present invention has been made in view of the above-described problems of the prior art, and fixes at low temperature, heat resistant storage stability, toner spent prevention, toner filming prevention, image quality after fixing, and image surface sticking prevention. An object of the present invention is to provide a toner excellent in toner.

  The present inventors disperse capsules containing a plasticizer and a hardly water-soluble substance in a toner binder resin, and the melting point of the plasticizer and the hardly water-soluble substance exceeds 60 ° C. It has high heat resistance during storage and development before fixing, and during fixing, the capsule is broken by the fixing pressure, so the binder resin is softened by the plasticizer, resulting in excellent low-temperature fixability and fixing of the fixed image. The inventors have found that this can be prevented and have completed the present invention.

That is, the said subject is solved by following (1)-(6) of this invention.
(1) A toner including at least a binder resin and a capsule, wherein the capsule includes at least a plasticizer that softens the binder resin and a poorly water-soluble substance in a core material, and a shell material is the plasticizer. The toner is characterized in that the plasticizer and the hardly water-soluble substance are not softened by the pressure, but are destroyed by applying a pressure equal to or higher than a predetermined pressure, and the melting point of the toner exceeds 60 ° C.
(2) The toner according to item (1), wherein the plasticizer and the poorly water-soluble substance do not form a solid solution.
(3) The toner according to (1) or (2), wherein the poorly water-soluble substance is wax.
(4) A developer comprising the toner according to any one of (1) to (3).
(5) an electrostatic latent image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and developing the electrostatic latent image with toner to make it visible At least developing means for forming an image, transfer means for transferring the visible image to a recording medium, and fixing means for fixing the transferred image transferred to the recording medium, wherein the toner comprises the first (1) An image forming apparatus comprising the toner according to any one of items (3) to (3).
(6) an electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image carrier, a developing step of developing the electrostatic latent image with toner to form a visible image, and At least a transfer step of transferring a visible image to a recording medium and a fixing step of fixing the transfer image transferred to the recording medium, wherein the toner is any one of (1) to (3) An image forming method comprising the toner according to claim 1.

As will be understood from the following detailed and specific explanation, according to the present invention, heat resistance is high during storage / development before fixing, no toner spent or toner filming occurs, and softening occurs quickly during fixing. In addition to being excellent in low-temperature fixability, it is possible to prevent sticking of fixed images.

Schematic sectional view showing an example of the toner of the present invention containing a capsule An example of the direct transfer system of the image forming apparatus (tandem type image forming apparatus) of the present invention is shown. 1 shows an example of an indirect transfer method of an image forming apparatus (tandem type image forming apparatus) of the present invention. 1 illustrates an example of a belt-type fixing unit in an image forming apparatus of the present invention. 1 illustrates an example of an electromagnetic induction heating type fixing unit in an image forming apparatus of the present invention. 1 shows an example of an ultrasonic vibration application type fixing unit in an image forming apparatus of the present invention. Schematic showing an example of an image forming apparatus of the present invention 4 shows another example of the image forming apparatus of the present invention. Enlarged view of each image forming element of FIG. An example of the process cartridge of this invention is shown

The toner of the present invention will be described in detail. The toner of the present invention contains at least a binder resin and a capsule, and further contains other components such as a colorant, a charge control agent, and an external additive as necessary.
FIG. 1 is a schematic sectional view showing an example of the toner of the present invention. In FIG. 1, a toner 201 has a binder resin 202, a capsule 204 containing a plasticizer and a hardly water-soluble substance, a colorant 203, a charge control agent 205, and an external additive 206.

<Capsule>
The capsule is a capsule that contains at least a plasticizer that softens the binder resin and a hardly water-soluble substance and is broken by a pressure equal to or higher than a predetermined pressure.
The predetermined pressure is a set pressure at the nip portion of the fixing unit of the image forming apparatus. If it is destroyed by fixing, there is no particular limitation, and it can be appropriately selected according to the purpose, but it is preferably more than 0.5 MPa, more preferably 1 MPa or more.
There is no restriction | limiting in particular as an upper limit of the said pressure, Although it can select suitably according to the objective, 5 MPa or less is preferable and 2 MPa or less is more preferable.

The greater the difference between the pressure (nip pressure) of the fixing unit (fixing unit) and the pressure applied to the toner in the developing unit or the like, the higher the durability of the toner.
However, if the pressure of the fixing unit is too high (for example, 10 MPa or more), it is necessary to make the mechanical configuration of the fixing unit robust, and the fixing unit becomes large and heavy. Assuming desktop and floor type copiers and printers used in general offices, if the size and weight of the fixing unit are important, the pressure applied to the fixing unit is usually 5 MPa or less, and 1 MPa or less. Is preferred.
On the other hand, it is estimated that the pressure when the toner is rubbed in the image forming apparatus is about 0.5 MPa or less.
Therefore, the capsule is preferably a capsule that is not broken at about 0.5 MPa and broken at a pressure of 1 MPa or more.
The strength of the capsule can be adjusted by the plasticizer in the capsule, the material constituting the shell, the thickness, and the like.

The capsules preferably have a particle size of 100 nm to 500 nm.
The lower limit of the capsule particle size affects the capsule breaking strength and solvent resistance. When encapsulating the plasticizer with a constant core-shell ratio in the capsule, the shell thickness decreases as the capsule particle size decreases. If the shell becomes too thin, the breaking strength of the capsules is weakened, and the capsules are easily broken during development and stirring, causing toner filming and toner spent.
Further, when the shell becomes too thin, the solvent resistance is deteriorated, and the plasticizer is eluted from the shell by the encapsulating plasticizer itself or the solvent used in the production of the toner. Therefore, the lower limit of the capsule particle size is preferably 100 nm or more, and more preferably 300 nm or more.

The upper limit of the particle size of the capsule affects the required diffusion distance of the plasticizer during fixing and the uniform dispersibility of the capsule inside the toner. When capsules are dispersed with a constant amount of capsules added to the interior of the toner particles, the distance between the capsules inside the toner particles increases as the particle size of the capsule increases. If the distance between the capsules becomes too large, the distance that the plasticizer has to diffuse increases in order to uniformly soften the entire binder resin in the toner particles, resulting in a longer fixing nip time. . A long fixing nip time is not preferable because it leads to a decrease in fixing nip pressure and enlargement of the apparatus configuration.

Also, if the capsules are dispersed with the toner particle size kept constant, the larger the capsule particle size, the easier the capsules are detached from the toner particles during toner granulation, and the capsules can be uniformly dispersed in the toner particles. It becomes difficult. Therefore, the upper limit of the capsule particle size is preferably 500 nm or less.

The particle diameter of the capsule can be determined by, for example, observing with a TEM (transmission electron microscope) or SEM (scanning electron microscope) and calculating an average value thereof. Moreover, the liquid which disperse | distributed the capsule can be measured by the dynamic light-scattering method using the thick type particle size analyzer FPAR-1000 (made by Otsuka Electronics Co., Ltd.).

(shell)
The capsule has a shell (outer shell) that is not softened by the plasticizer. The term “not softened” in the present invention means that the shell material is not substantially dissolved, swelled, permeated or plasticized by the plasticizer.

The shell (outer shell) of the capsule is not particularly limited as long as it is a shell that is not softened by the plasticizer, and can be appropriately selected according to the purpose.
Examples of the material of the shell include a resin. Examples of the resin include resins made of vinyl monomers, polyester resins, polyamide resins, polyether resins, polyurethane resins, polyurea resins, polycarbonate resins, melamine resins, phenol resins, and resins formed by crosslinking these resins. Etc.
These resins may be used alone or in combination.

The capsule of the present invention has a relatively high melting point of the plasticizer and the hardly water-soluble substance, and is present in a solid state except for fixing, so that sufficient strength can be obtained even if the shell is thinned, and a sufficient amount of plasticizer Can be included.
The core-shell ratio (encapsulation rate) of the capsule is not particularly limited, but the content of the core agent with respect to the whole capsule is preferably 50% or more and 90% or less, more preferably 60% or more and 80% or less. It is.
If the encapsulation rate is less than 50%, the amount of capsules required to soften the binder resin increases, and if it is 90% or more, the shell material becomes too thin and the capsule strength decreases.

(Plasticizer)
The plasticizer contained in the capsule of the present invention softens the binder resin and has a melting point exceeding 60 ° C.
When the melting point of the plasticizer is 60 ° C. or lower, the inside of the developing machine may be heated up to a maximum of around 60 ° C., so that the capsule inside becomes a liquid in the developing machine and the breaking strength of the capsule is reduced. When the toner is destroyed, toner filming and toner spent occur.
On the other hand, if the melting point of the plasticizer is too high, a high temperature is required to melt the plasticizer at the time of fixing, and thus low temperature fixing is not possible. Therefore, the melting point of the plasticizer is preferably 80 ° C. or lower.

If the melting point of the said plasticizer exceeds 60 degreeC, there will be no restriction | limiting in particular, According to the binder resin to be used and the objective, it can select suitably.
For example, aromatic esters, aromatic ethers, aromatic acid anhydrides, aliphatic esters, aliphatic acid anhydrides and the like can be mentioned.

More specifically, 1,2-diacetoxybenzene, 2-naphthyl acetate, 2-naphthyl laurate, p-tolyl phenyl acetate, diphenyl carbonate, phenyl benzoate, diphenyl phthalate, dicyclohexyl phthalate, dimethyl isophthalate, Ethylene glycol dibenzoate, phthalide, coumarin, 6-methylcoumarin, 1,4-diethoxybenzene, 2-methoxynaphthalene, 4-methoxybenzophenone, 4-methoxychalcone, 6-methoxy-1-tetralone, 4-methoxyphenylacetic acid Anhydride, phenoxyacetic anhydride, dimethyl octadecanedioate, trimethyl citrate, pentaerythritol tetraacetate, pentaerythritol tetrastearate, tristearin, stearic anhydride, n-octyl succinic anhydride, deci Succinic anhydride, 3,3-tetramethylene glutaric anhydride, and 3,3-pentamethylene glutaric anhydride.
These plasticizers may be used alone or in combination.

The content of the plasticizer is preferably 10 parts by mass or more and 30 parts by mass or less, and more preferably 15 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the binder resin.
When the amount of the plasticizer exceeds 30 parts by mass, the binder resin is excessively softened and the toner is offset to cause image disturbance. The binder resin having an amount of the plasticizer of less than 10 parts by mass may not be sufficiently softened and the low-temperature fixability may be lowered.

(Slightly water-soluble substance)
In the present invention, the poorly water-soluble substance is a hydrophobic substance having a solubility in water at 25 ° C. of less than 1 g / L, and can stabilize small oil droplets in water and produce a small-diameter capsule. It is to make.

The poorly water-soluble substance in the present invention has a melting point exceeding 60 ° C. Further, if the melting point of the poorly water-soluble substance is 60 ° C. or lower, the temperature inside the developing machine may rise to a maximum of around 60 ° C., so that the capsule inside becomes liquid in the developing machine and the capsule breaking strength is reduced. When the capsule is broken, toner filming and toner spent occur.

It is preferable that the poorly water-soluble substance in the present invention does not form a solid solution with the plasticizer. When the poorly water-soluble substance and the plasticizer form a solid solution, the melting point of the core material in the capsule is lowered due to the lowering of the freezing point, and when the temperature inside the developing machine is increased to around 60 ° C, the inside of the capsule becomes liquid in the developing machine The breaking strength is lowered, and the toner filming and toner spent are generated by breaking the capsule.

On the other hand, above the melting point of both the plasticizer and the hardly water-soluble substance, both the plasticizer and the hardly water-soluble substance are melted and exist in a liquid, and are more easily dissolved than in the solid state. Therefore, when the capsule is produced by maintaining the temperature above the melting point of both the plasticizer and the hardly water-soluble substance, the effect of the hardly water-soluble substance stabilizing the fine oil droplets can be exhibited without any problem.

The poorly water-soluble substance in the present invention is more preferably a wax.
In recent years, it has been common to add wax to the toner for oil-less fixing, and adding this to the capsule does not have any adverse effect on the properties of the entire toner, In addition, the amount of wax added to the toner particles can be reduced.
It is difficult to disperse the wax in the toner particles, and the wax is usually dispersed in the toner by using a wax dispersant in combination. For this reason, it is preferable to use a slightly water-soluble substance as a wax because the amount of the wax dispersant required is reduced.

In addition, the poorly water-soluble substance in the present invention preferably has a low molecular weight as much as possible within a range where the melting point can be maintained at 60 ° C. or higher. When the poorly water-soluble substance has a high molecular weight, the melt viscosity of the oil phase at the time of capsule production becomes high and it becomes difficult to emulsify into fine oil droplets.

As the poorly water-soluble substance in the present invention, various materials such as shellac wax, carnauba wax, paraffin wax, montan wax, polyethylene wax, and polypropylene wax can be used.

In the present invention, the mixing ratio of the poorly water-soluble substance and the plasticizer is preferably in the range of 5:95 to 10:90 by mass ratio.
When the amount of the hardly water-soluble substance is less than 5% by mass, the effect of stabilizing the fine oil droplets is small, and a capsule with a small diameter cannot be obtained. If the poorly water-soluble substance is 10% by mass or more, it cannot be dissolved in the plasticizer, the effect of stabilizing the fine oil droplets cannot be obtained, and the capsules with a small diameter cannot be obtained. Also, since the proportion of plasticizer in the capsule is reduced, more capsules must be dispersed in the toner particles to soften the toner.

(Capsule manufacturing method)
The method for producing the capsule is not particularly limited and may be appropriately selected depending on the intended purpose. At the time of production, a method of encapsulating a monomer that becomes a shell material by adding it to an aqueous phase that is a continuous phase is preferable. An example of such an encapsulation method is an in situ polymerization method.

Unlike the above method, in the method of adding the monomer to both the oil phase and the water phase oil phase, even if the monomer in the oil phase is polymerized, a trace amount of monomer or oligomer remains in the oil phase, which is an impurity. In order to lower the melting point of the plasticizer and / or the hardly water-soluble substance, when the temperature in the developing machine rises, the plasticizer and the poorly water-soluble substance inside the capsule becomes a liquid, and the breaking strength of the capsule decreases, When the capsule is broken, toner filming or toner spent occurs.
Furthermore, the phase separation between the monomer, the plasticizer and the poorly water-soluble substance in the fine oil droplets does not occur rapidly, resulting in a capsule with a matrix structure rather than a core-shell structure, resulting in a capsule with poor solvent resistance. End up.

<Binder resin>
The binder resin is not particularly limited as long as it is a resin softened by a plasticizer, and can be appropriately selected according to the purpose.
For example, a styrene monomer, an acrylic monomer, a methacrylic monomer alone or a polymer comprising two or more types; polyester resin, polyol resin, polyurethane resin, furan resin, epoxy resin, xylene resin, terpene Examples thereof include resins, coumarone indene resins, polycarbonate resins, and petroleum resins. These resins may be used alone or in combination of two or more.

In particular, from the viewpoint of low-temperature fixability, a resin having a molecular weight controlled by an extension reaction using the modified polyester resin (i) and the unmodified polyester resin (ii) is preferable.

(Modified polyester)
In the present invention, the modified polyester (i) refers to a state in which a bonding group other than an ester bond exists in the polyester resin, or resin components having different configurations are bonded to each other by a covalent bond, an ionic bond, or the like in the polyester resin. .
Specifically, the polyester terminal is modified by introducing a functional group such as a carboxylic acid group or an isocyanate group that reacts with a hydroxyl group into the polyester terminal and further reacting with an active hydrogen-containing compound.

Examples of the modified polyester (i) include urea-modified polyester obtained by a reaction between a polyester prepolymer (A) having an isocyanate group and amines (B).

As the polyester prepolymer (A) having an isocyanate group, a polyester having a polycondensate of a polyhydric alcohol (PO) and a polyvalent carboxylic acid (PC) and having an active hydrogen group is further added to a polyvalent isocyanate compound (PIC). And those reacted with.

Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable.

Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use.

The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) with a small amount of (TC) Mixtures are preferred.

Divalent carboxylic acids (DIC) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms.

Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) ); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1.
When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.

The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. .
If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.

The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acid block of B1 to B5 (B6).

Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexyl). Methane, diamine cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like.
Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine.
Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
Examples of the compound (B6) obtained by blocking the amino group of B1 to B5 include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

The ratio of the amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of the isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and the amino groups [NHx] in the amines (B). Is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2.
When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.

The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70.
When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

This modified polyester (i) is produced by a one-shot method or a prepolymer method.
The weight average molecular weight of the modified polyester (i) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000.
The peak molecular weight at this time is preferably 1000 to 10000. When the molecular weight is less than 1000, the elongation reaction hardly occurs, the elasticity of the toner is small, and as a result, the resistance to hot offset deteriorates. On the other hand, when it exceeds 10,000, the problem in production becomes high in the deterioration of fixability, particle formation and pulverization.
The number average molecular weight of the modified polyester (i) is not particularly limited when the unmodified polyester (ii) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. (I) When used alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color device are deteriorated.

In the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B) to obtain the modified polyester (i), a reaction terminator is used as necessary to adjust the molecular weight of the resulting urea-modified polyester. be able to.

Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

(Unmodified polyester)
Examples of the unmodified polyester (ii) include polycondensates of polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) similar to the polyester component of the modified polyester (i). ).
The unmodified polyester (ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, such as a urethane bond.

The modified polyester (i) and the unmodified polyester (ii) are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance.
Therefore, it is preferable that the polyester component of the modified polyester (i) and (ii) have a similar composition.
When the unmodified polyester (ii) is contained, the weight ratio of (i) to (ii) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25 / 75, particularly preferably 7/93 to 20/80.
When the weight ratio of the modified polyester (i) is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The peak molecular weight of unmodified polyester (ii) is usually 1000 to 10000, preferably 2000 to 8000, and more preferably 2000 to 5000.
If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate.

The hydroxyl value of the unmodified polyester (ii) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

As for the acid value of unmodified polyester (ii), 1-5 are preferable, More preferably, it is 2-4. Since a high acid value wax is used as the wax, the low acid value binder leads to electrification and high volume resistance, so that it is easy to match the toner used for the two-component developer.

The glass transition point (Tg) of the binder resin is usually 35 to 70 ° C, preferably 55 to 65 ° C.
If it is less than 35 ° C., the heat resistant storage stability of the toner is deteriorated, and if it exceeds 70 ° C., the low-temperature fixability is insufficient. In the toner of the present invention, urea-modified polyester tends to be present on the surface of the obtained toner base particles, and therefore has a tendency to have good heat-resistant storage stability even when the glass transition point is low, as compared with known polyester-based toners. Show.

(Binder resin production method)
The binder resin can be produced by the following method.
Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having hydroxyl groups. Subsequently, at 40-140 degreeC, this is made to react with a polyvalent isocyanate compound (PIC), and the prepolymer (A) which has an isocyanate group is obtained. Further, (A) is reacted with amines (B) at 0 to 140 ° C. to obtain polyester (i) modified with a urea bond.
When reacting (PIC) and when reacting (A) and (B), a solvent may be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers Inactive to polyvalent isocyanate compounds (PIC) such as benzene (such as tetrahydrofuran).
When the unmodified polyester (ii) is used in combination, (ii) is produced in the same manner as the polyester having a hydroxyl group, and this is dissolved and mixed in the solution after the completion of the reaction (i).

<Other ingredients>
In addition to the binder resin and capsule, the toner of the present invention may contain a colorant, inorganic fine particles, a magnetic material, a charge control agent, an external additive, a fluidity improver, a cleaning property improver, a metal soap, if necessary. Etc. Other components can be contained.

(Coloring agent)
The colorant is not particularly limited and may be appropriately selected from known dyes and pigments according to the purpose. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G , G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR ), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Lead Red, Lead Red, Cadmium Red, Cadmium Mummer Curry Red, Antimony Zhu, Permanent Red 4R, Parare , Phi Sae Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake B, rhodamine lake Y, alizarin lake, thioindigo red B, thioindigo maroon, oil Quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkaline blue rake, peacock blue rake, Victoria blue rake, metal-free phthalocyanine blue, phthalocyanine blue , Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome oxide, pyridian, emerald green, pigment green B, naphthol green B, green gold, acid Examples include lean lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, and lithopone. These may be used individually by 1 type and may use 2 or more types together.

The colorant can also be used as a master batch combined with a resin.
There is no restriction | limiting in particular as resin kneaded with the said masterbatch, According to the objective, it can select suitably.

(Inorganic fine particles)
Examples of the inorganic fine particles include silica, alumina titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, Examples thereof include chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. In addition, it is preferable to subject these surfaces to a hydrophobizing treatment because the dispersibility in the binder resin is improved.

The presence of inorganic fine particles having appropriate characteristics inside the toner makes it possible to achieve fine dispersion of the binder resin, the colorant, and the wax that are toner components. This is because, due to the presence of the inorganic fine particles, a mixing share due to the filler effect is applied to these toner components, and uniform mixing is possible.

There is no restriction | limiting in particular as an average primary particle size (henceforth an average particle size) of the said inorganic fine particle, Although it can select suitably according to the objective, 10 nm-1,000 nm are preferable, and 50 nm-600 nm are more preferable. .
When the average primary particle size is less than 10 nm, the inorganic fine particles are likely to aggregate, and the volume specific resistance value of the toner may be decreased and the dispersion of the toner component may be deteriorated. On the other hand, when the average primary particle size exceeds 1,000 nm, the dispersion effect due to the filler effect may not be obtained.
The inorganic fine particles can also be used as an external additive.

(Magnetic material)
The magnetic material is not particularly limited and can be appropriately selected depending on the purpose. For example, iron oxide containing magnetic iron oxide such as magnetite, maghemite, ferrite, and other metal oxides; iron, Metals such as cobalt and nickel, or these metals and metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium Alloys thereof; and mixtures thereof.

Specific examples of the magnetic material include, for example, Fe ₃ O ₄ , γ-Fe ₂ O ₃ , ZnFe ₂ O ₄ , Y ₃ Fe ₅ O ₁₂ , CdFe ₂ O ₄ , Gd ₃ Fe ₅ O ₁₂ , CuFe ₂ O. ₄ , PbFe ₁₂ O, NiFe ₂ O ₄ , NdFe ₂ O, BaFe ₁₂ O ₁₉ , MgFe ₂ O ₄ , MnFe ₂ O ₄ , LaFeO ₃ , iron powder, cobalt powder, nickel powder and the like.
These may be used individually by 1 type and may be used in combination of 2 or more type. Among these, fine powders of Fe ₃ O ₄ and γ-Fe ₂ O ₃ are particularly preferable.

Further, magnetic iron oxides such as magnetite, maghemite, and ferrite containing different elements, or a mixture thereof can be used.

Examples of the different elements include lithium, beryllium, boron, magnesium, aluminum, silicon, phosphorus, germanium, zirconium, tin, sulfur, calcium, scandium, titanium, vanadium, chromium, manganese, cobalt, nickel, copper, zinc, Examples include gallium. Among these, magnesium, aluminum, silicon, phosphorus, and zirconium are preferable.

The heterogeneous element may be incorporated in the iron oxide crystal lattice, may be incorporated in the iron oxide as an oxide, or may be present on the surface as an oxide or a hydroxide. Is preferably contained as an oxide.
The different elements can be incorporated into the particles by mixing the salts of the different elements at the time of producing the magnetic substance and adjusting the pH. Moreover, it can precipitate on the particle | grain surface by adjusting pH after magnetic body particle | grain production | generation, or adding salt of each element and adjusting pH.

There is no restriction | limiting in particular as content of the said magnetic body, Although it can select suitably according to the objective, 10 mass parts-200 mass parts of magnetic bodies are preferable with respect to 100 mass parts of said binder resins, 20 Mass parts to 150 parts by mass are more preferable.

There is no restriction | limiting in particular as a number average particle diameter of the said magnetic body, Although it can select suitably according to the objective, 0.1 micrometer-2 micrometers are preferable, and 0.1 micrometer-0.5 micrometer are more preferable.
The number average diameter can be obtained by measuring a photograph taken with a transmission electron microscope with a digitizer or the like.

The magnetic properties of the magnetic material are not particularly limited and may be appropriately selected according to the purpose. However, the magnetic properties at 10 K oersted application are coercive force 20 oersted to 150 oersted and saturation magnetization 50 emu / g to Those having 200 emu / g and residual magnetization of 2 emu / g to 20 emu / g are preferable.

The magnetic material can also be used as a colorant.

(Charge control agent)
The charge control agent is not particularly limited and may be appropriately selected according to the purpose. Examples thereof include nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, and molybdate chelate pigments. , Rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, salicylic acid derivatives And metal salts thereof.

A commercially available product can be used as the charge control agent. Examples of the commercially available products include Nigrosine dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, and salicylic acid metal. Complex E-84, phenol-based condensate E-89 (above, Orient Chemical Industries, Ltd.); quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Industries, Ltd.); LRA-901, LR-147 which is a boron complex (manufactured by Nippon Carlit Co., Ltd.); copper phthalocyanine, perylene, quinacridone, azo pigment, other polymer systems having functional groups such as sulfonic acid group, carboxyl group, quaternary ammonium salt And the like.

The content of the charge control agent is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.1 parts by mass to 10 parts by mass with respect to 100 parts by mass of the binder resin. 0.2 mass part-5 mass parts are more preferable.
When the content exceeds 10 parts by mass, the chargeability of the toner is too large, the effect of the main charge control agent is reduced, the electrostatic attraction force with the developing roller is increased, and the flowability of the developer is reduced. The image density may be reduced.

The charge control agent can be dissolved and dispersed after being melt-kneaded with a masterbatch and a binder resin, or, of course, may be added when directly dissolving or dispersing in an organic solvent. Further, after the toner base particles are prepared, they may be fixed on the surface thereof.

(External additive)
The external additive is not particularly limited and may be appropriately selected depending on the intended purpose. For example, silica fine particles, hydrophobized silica fine particles, fatty acid metal salts (for example, zinc stearate, aluminum stearate, etc.) Metal oxides (for example, titania, alumina, tin oxide, antimony oxide, etc.) or their hydrophobized materials, fluoropolymers, etc.
Among these, hydrophobized silica fine particles, titania fine particles, and hydrophobized titania fine particles are preferable.

Examples of the silica fine particles include R972, R974, RX200, RY200, R202, R805, and R812 (all manufactured by Nippon Aerosil Co., Ltd.).

Examples of the titania fine particles include P-25 (manufactured by Nippon Aerosil Co., Ltd.); STT-30, STT-65C-S (both manufactured by Titanium Industry Co., Ltd.); TAF-140 (manufactured by Fuji Titanium Industry Co., Ltd.). MT-150W, MT-500B, MT-600B, MT-150A (all manufactured by Teika Co., Ltd.), etc.
Examples of the hydrophobic titania fine particles include T-805 (manufactured by Nippon Aerosil Co., Ltd.); STT-30A, STT-65S-S (both manufactured by Titanium Industry Co., Ltd.); TAF-500T, TAF-1500T ( Both are manufactured by Fuji Titanium Industry Co., Ltd.); MT-100S, MT-100T (both manufactured by Teika Co., Ltd.); IT-S (made by Ishihara Sangyo Co., Ltd.) and the like.

The hydrophobized silica fine particles, the hydrophobized titania fine particles, and the hydrophobized alumina fine particles can be obtained by treating hydrophilic fine particles with a hydrophobizing agent (hydrophobizing treatment).

Examples of the hydrophobizing agent include silane coupling agents such as dialkyl dihalogenated silane, trialkyl halogenated silane, alkyl trihalogenated silane, and hexaalkyldisilazane, silylating agents, and silane cups having a fluorinated alkyl group. Examples thereof include a ring agent, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, and silicone varnish.

In addition, silicone oil-treated inorganic fine particles obtained by treating silicone oil with inorganic fine particles (treating with heat as necessary) are also preferable.
Examples of the inorganic fine particles include silica, alumina, titanium dioxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, silica sand, clay, mica, Examples include wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, parium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these, silica and titanium dioxide are particularly preferable.

Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, chlorophenyl silicone oil, methyl hydrogen silicone oil, alkyl-modified silicone oil, fluorine-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, amino acid. Modified silicone oil, epoxy modified silicone oil, epoxy / polyether modified silicone oil, phenol modified silicone oil, carboxyl modified silicone oil, mercapto modified silicone oil, acrylic or methacryl modified silicone oil, α-methylstyrene modified silicone oil, etc. .
There is no restriction | limiting in particular as an average particle diameter of the primary particle of the said inorganic fine particle, Although it can select suitably according to the objective, 1 nm-100 nm are preferable and 3 nm-70 nm are more preferable. If the average particle size is less than 1 nm, the inorganic fine particles may be buried in the toner, and the function may not be exhibited effectively. May end up.

Resin fine particles can also be used as the external additive. Examples of the resin fine particles include polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization; copolymers of methacrylic acid esters and acrylic acid esters; condensation polymerization systems such as silicone, benzoguanamine, and nylon; thermosetting Examples thereof include polymer particles made of a resin. By using such resin fine particles together with the machine fine particles, the chargeability of the toner can be enhanced, the reversely charged toner can be reduced, and the background stain can be reduced.
There is no restriction | limiting in particular as content of the said resin fine particle, Although it can select suitably according to the objective, 0.01 mass%-5 mass% are preferable, and 0.1 mass%-2 mass% are more preferable. .

There is no restriction | limiting in particular as content of the said external additive, Although it can select suitably according to the objective, 0.1 mass%-5 mass% are preferable, and 0.3 mass%-3 mass% are more. preferable.

(Fluidity improver)
The fluidity improver is capable of surface treatment to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylated Agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like.

(Cleaning improver)
The cleaning property improving agent is added to the toner in order to remove the developer after transfer remaining on the electrostatic latent image carrier and the intermediate transfer member.
Examples of the cleaning property improver include fatty acid metal salts such as zinc stearate, calcium stearate and stearic acid; polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and more preferably have a volume average particle size of 0.01 μm to 1 μm.

<Toner production method>
The toner production method is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the pulverization method, suspension polymerization method, dissolution suspension method, emulsion aggregation method, spray granulation method, polyester elongation Law. Among these, the polyester elongation method is preferable. Details of the production of toner using the polyester elongation method will be described below.

(1) A toner material solution is prepared by dispersing a colorant, unmodified polyester (ii), a polyester prepolymer (A) having an isocyanate group, a release agent, and the capsules in an organic solvent.
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation.

Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl Isobutyl ketone etc. can be used individually or in combination of 2 or more types. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

(2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone, or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). May be included.

The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight.
If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical.

Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.
As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, fatty acid amide derivatives, polyhydric alcohols Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine And the like.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkyl carboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctane sulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) par Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned. Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

Further, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. , Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footgent F-300 (Neos), and the like.

The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is in the range of 10 to 90%.
For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao Corporation), SGP (manufactured by Soken Co., Ltd.), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.).

In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

As a dispersant that can be used in combination with the above resin fine particles and inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid-γ-hydroxypropyl, methacrylic acid-γ-hydroxy Propyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Luric acid esters, N-methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and a carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl Nitrogen compounds such as imidazole and ethyleneimine, or homopolymers or copolymers such as those having a heterocyclic ring thereof, polyoxyethylene, poly Xoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxy Polyoxyethylenes such as ethylene nonylphenyl ester, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

(3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group.
This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

(4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . In addition, when a calcium phosphate salt or other acid that is soluble in alkali is used as a dispersion stabilizer, the calcium phosphate salt is removed from the toner base particles by dissolving the calcium phosphate salt with an acid such as hydrochloric acid and then washing with water. To do. It can also be removed by operations such as enzymatic degradation.

(5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.
The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the true spherical shape and the rugby ball shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. be able to.

<Developer>
The developer of the present invention comprises the toner of the present invention described above. The toner of the present invention may be used as a one-component developer, or may be mixed with a carrier and used as a two-component developer. Among these, the two-component developer is preferable from the viewpoint of improving the service life when used in a high-speed printer or the like corresponding to the recent improvement in information processing speed.

In the case of the one-component developer using the toner, even if the balance of the toner is performed, the fluctuation of the toner particle diameter is small, the filming of the toner on the developing roller, and a blade for thinning the toner The toner is not fused to the layer thickness regulating member such as the like, and good and stable developability and image can be obtained even when the developing means is used (stirred) for a long time.

Further, in the case of the two-component developer using the toner, even if the toner balance is maintained over a long period of time, the toner particle diameter in the developer is small, and even if it is stirred for a long time in the developing means, it is good and stable. Developability is obtained.

<Career>
There is no restriction | limiting in particular as said carrier, Although it can select suitably according to the objective, What has a core material and the resin layer which coat | covers this core material is preferable.

(Core material)
The material of the core material is not particularly limited and may be appropriately selected depending on the intended purpose. However, 50 emu / g to 90 emu / g manganese-strontium (Mn—Sr) based material, manganese-magnesium (Mn— Mg) -based materials and the like are preferable, and highly magnetized materials such as iron powder (100 emu / g or more) and magnetite (75 emu / g to 120 emu / g) are preferable in terms of securing image density. Also, the weakness of the copper-zinc (Cu-Zn) system (30 emu / g to 80 emu / g) is advantageous in that it can weaken the contact with the photoconductor in which the toner is in a spiked state and is advantageous in improving the image quality. Magnetized materials are preferred. These may be used alone or in combination of two or more.

There is no restriction | limiting in particular as a particle size of the said core material, Although it can select suitably according to the objective, 10 micrometers-200 micrometers are preferable at an average particle diameter (mass average particle diameter (D50)), and 40 micrometers-100 micrometers are preferable. More preferred.
When the average particle diameter (weight average particle diameter (D50)) is less than 10 μm, in the distribution of carrier particles, the fine powder system increases, the magnetization per particle is lowered, and carrier scattering may occur. If it exceeds 200 μm, the specific surface area may decrease and toner scattering may occur, and in the case of a full color with many solid portions, reproduction of the solid portions may be particularly poor.

(Resin layer)
The material of the resin layer is not particularly limited and may be appropriately selected depending on the purpose. For example, amino resin, polyvinyl resin, polystyrene resin, halogenated olefin resin, polyester resin, polycarbonate resin , Polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexafluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, vinylidene fluoride and vinyl fluoride For example, fluoroterpolymers such as terpolymers of tetrafluoroethylene, vinylidene fluoride and non-fluorinated monomers, and silicone resins. These may be used individually by 1 type and may use 2 or more types together.

There is no restriction | limiting in particular as said silicone resin, According to the objective, it can select suitably, For example, straight silicone resin which consists only of organosilosan bonds; alkyd resin, polyester resin, epoxy resin, acrylic resin, urethane resin, etc. Modified silicone resins modified with

A commercial item can be used as said silicone resin.
Examples of the straight silicone resin include KR271, KR255, and KR152 manufactured by Shin-Etsu Chemical Co., Ltd .; SR2400, SR2406, and SR2410 manufactured by Toray Dow Corning Silicone Co., Ltd.
Examples of the modified silicone resin include KR206 (alkyd modified), KR5208 (acrylic modified), ES1001N (epoxy modified), KR305 (urethane modified) manufactured by Shin-Etsu Chemical Co., Ltd .; manufactured by Toray Dow Corning Silicone Co., Ltd. SR2115 (epoxy modification), SR2110 (alkyd modification), and the like.

The silicone resin can be used alone, but a component that undergoes a crosslinking reaction, a charge amount adjusting component, and the like can also be used at the same time.

The resin layer may contain conductive powder or the like as necessary. Examples of the conductive powder include metal powder, carbon black, titanium oxide, tin oxide, and zinc oxide. The average particle diameter of these conductive powders is preferably 1 μm or less. When the average particle diameter exceeds 1 μm, it may be difficult to control electric resistance.

For example, the resin layer is prepared by dissolving the silicone resin or the like in a solvent to prepare a coating solution, and then uniformly coating the coating solution on the surface of the core material by a known coating method, drying, and baking. It can be formed by doing. Examples of the coating method include a dipping method, a spray method, and a brush coating method.
The solvent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cellosolve, and butyl acetate.

There is no restriction | limiting in particular as said baking method, According to the objective, it can select suitably, For example, an external heating system may be sufficient and an internal heating system may be sufficient.
The baking apparatus is not particularly limited and may be appropriately selected according to the purpose. For example, a stationary electric furnace, a fluid electric furnace, a rotary electric furnace, a burner furnace, an apparatus equipped with a microwave, etc. Is mentioned.

The amount of the resin layer in the carrier is preferably 0.01% by mass to 5.0% by mass. When the amount is less than 0.01% by mass, the uniform resin layer may not be formed on the surface of the core material. When the amount exceeds 5.0% by mass, the resin layer becomes thick. In some cases, granulation of carriers occurs, and uniform carrier particles may not be obtained.

When the developer is a two-component developer, the content of the carrier in the developer is not particularly limited and may be appropriately selected depending on the intended purpose, but is 90% by mass to 98% by mass. Is preferable, and 93 mass%-97 mass% is more preferable.

<Toner container>
The toner-containing container of the present invention contains the toner of the present invention in a container.
There is no restriction | limiting in particular as said container containing a toner, It can select suitably from well-known things, For example, the thing etc. which have a developer container main body and a cap are mentioned. There is no restriction | limiting in particular about the magnitude | size, a shape, a structure, a material, etc. as said developer container main body, According to the objective, it can select suitably. As the shape of the developer container main body, for example, the cylindrical shape is preferable, spiral irregularities are formed on the inner peripheral surface, and the toner as the contents can be transferred to the discharge port side by rotating, In addition, it is particularly preferable that part or all of the spiral portion has a bellows function. The material of the developer container main body is not particularly limited, and those having good dimensional accuracy are preferable. For example, a resin is preferably used. Among them, for example, polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, Preferable examples include vinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, and polyacetal resin. The developer-containing container is easy to store and transport, has excellent handleability, and can be suitably used for replenishing the developer by being detachably attached to a process cartridge described later.

<Image Forming Apparatus and Image Forming Method>
The image forming apparatus of the present invention includes at least an electrostatic latent image carrier, an electrostatic latent image forming unit, a developing unit, a transfer unit, and a fixing unit, and, if necessary, other units, For example, it has a static elimination means, a cleaning means, a recycling means, a control means, etc.
The image forming method of the present invention includes at least an electrostatic latent image forming step, a developing step, a transfer step, and a fixing step, and further, if necessary, other steps such as a static elimination step, a cleaning step, and a recycling step. Process, control process, etc.

The image forming method of the present invention can be suitably performed by the image forming apparatus of the present invention, the electrostatic latent image forming step can be performed by the electrostatic latent image forming unit, and the developing step can be The transfer unit can be performed by the developing unit, the transfer step can be performed by the transfer unit, the fixing step can be performed by the fixing unit, and the other steps can be performed by the other unit. Can do.

(Electrostatic latent image forming step and electrostatic latent image forming means)
The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image carrier.
The material, shape, structure, size and the like of the electrostatic latent image carrier (hereinafter sometimes referred to as “photosensitive member”) are not particularly limited and can be appropriately selected from known ones. .
Examples of the material include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferable in terms of long life. Examples of the shape of the electrostatic latent image carrier include a drum shape, a sheet shape, and an endless belt shape.

The structure of the electrostatic latent image carrier may be a single layer structure or a laminated structure.
The size of the electrostatic latent image carrier is not particularly limited and can be appropriately selected according to the purpose, and can be appropriately selected according to the size and specifications of the image forming apparatus.

As the amorphous silicon photoreceptor, for example, a support is heated to 50 ° C. to 400 ° C., and a vacuum deposition method, a sputtering method, an ion plating method, a thermal CVD method, a photo CVD method, a plasma CVD method is applied on the support. A photoconductor having a photoconductive layer made of a-Si can be used by a film forming method such as the above. Among these, a plasma CVD method, that is, a method in which a source gas is decomposed by direct current, high frequency or microwave glow discharge to form an a-Si deposited film on a support is preferable.

The electrostatic latent image can be formed, for example, by charging the surface of the electrostatic latent image carrier and then exposing it like an image, and by the electrostatic latent image forming means. .
The electrostatic latent image forming means includes at least charging means for charging the surface of the electrostatic latent image carrier and exposure means for exposing the surface of the electrostatic latent image carrier imagewise.

(Charging means)
The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charging unit.
The charging means is not particularly limited and may be appropriately selected depending on the purpose. For example, a known contact charger including a conductive or semiconductive roller, brush, film, rubber blade, etc. And non-contact chargers utilizing corona discharge such as corotron and scorotron.

The shape of the charging means may take any form such as a magnetic brush or a fur brush in addition to a roller, and can be selected according to the specifications and form of the image forming apparatus.
When the magnetic brush is used as the charging means, the magnetic brush includes, for example, various ferrite particles such as Zn-Cu ferrite as the charging means, and is included in a nonmagnetic conductive sleeve for supporting it. It consists of a magnet roll.
When the fur brush is used as the charging means, for example, a fur treated with carbon, copper sulfide, metal, or metal oxide is used as the material of the fur brush. It can be used as a charging means by winding or sticking it on gold.
The charging unit is not limited to the contact type charging unit, but it is preferable to use a contact type charging unit because an image forming apparatus in which ozone generated from the charging unit is reduced can be obtained.

(Exposure means)
The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure unit.
The exposure unit is not particularly limited and may be appropriately selected depending on the intended purpose as long as the surface of the electrostatic latent image carrier charged by the charging unit can be exposed like an image to be formed. Examples thereof include various exposure means such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system.
The light source used for the exposure means is not particularly limited and may be appropriately selected according to the purpose. For example, a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser General light emitting materials such as (LD) and electroluminescence (EL).
In addition, various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.
In the present invention, a back light system in which imagewise exposure is performed from the back side of the electrostatic latent image carrier may be employed.

(Development process and development means)
The developing step is a step of developing the electrostatic latent image using a toner or a developer to form a visible image.
The toner of the present invention is used as the toner.
As the developer, the developer of the present invention is used.
The visible image can be formed, for example, by developing the electrostatic latent image using the toner or the developer, and can be performed by the developing unit.
The developing means is not particularly limited as long as it can be developed using the toner or developer, and can be appropriately selected from known ones. For example, the toner or developer is contained, Preferable examples include those having at least a developing unit capable of applying the toner or the developer to the electrostatic latent image in a contact or non-contact manner.

The developing unit may be a dry developing type, a wet developing type, a single color developing unit, or a multi-color developing unit. For example, a toner having a stirrer for charging the toner or the developer by frictional stirring and a rotatable magnet roller is preferable.

In the developing device, for example, the toner and the carrier are mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. . Since the magnet roller is disposed in the vicinity of the electrostatic latent image carrier, a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrostatically attracted by the static force. It moves to the surface of the electrostatic latent image carrier. As a result, the electrostatic latent image is developed with the toner, and a visible image is formed with the toner on the surface of the electrostatic latent image carrier.

The developer accommodated in the developing means is the developer containing the toner, but the developer may be a one-component developer or a two-component developer.
As the one-component developing means, for example, a one-component developing device having a developer carrier to which the toner is supplied and a layer thickness regulating member that forms a thin layer of toner on the surface of the developer carrier is preferable. Used.

(Transfer process and transfer means)
The transfer step is not particularly limited as long as it is a step of transferring the visible image to a recording medium, and can be appropriately selected according to the purpose. For example, the transfer step is performed using a transfer unit.
The transfer unit may be a transfer unit that directly transfers a visible image on the electrostatic latent image carrier to a recording medium, or an intermediate transfer member is used, and the visible image is primarily transferred onto the intermediate transfer member. It may be a secondary transfer means for secondary transfer of the visible image onto the recording medium after the transfer.
The transfer can be performed, for example, by charging the visible image with the electrostatic latent image carrier using a transfer charger, and can be performed by the transfer unit. The transfer means includes a primary transfer means for transferring a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer means for transferring the composite transfer image onto a recording medium. Embodiments are preferred.
Here, when the image to be secondarily transferred onto the recording medium is a color image composed of a plurality of colors of toner, the toner of each color is sequentially superimposed on the intermediate transfer member by the transfer means. An image can be formed on the body, and the image on the intermediate transfer body can be collectively transferred onto the recording medium by the intermediate transfer unit.
The intermediate transfer member is not particularly limited and can be appropriately selected from known transfer members according to the purpose. For example, a transfer belt and the like are preferable.

The transfer unit (the primary transfer unit and the secondary transfer unit) has at least a transfer unit that peels and charges the visible image formed on the electrostatic latent image carrier to the recording medium side. Is preferred. There may be one transfer means or two or more transfer means. Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.

These transfer units are also preferably used in a tandem type image forming apparatus.
The tandem type image forming apparatus has a plurality of image forming elements including at least an electrostatic latent image carrier, a charging unit, a developing unit, and a transfer unit. In this tandem type image forming apparatus, four image forming elements for yellow, magenta, cyan, and black are mounted, and each visible image is created in parallel with the four image forming elements, and is recorded on a recording medium or an intermediate transfer member. Therefore, a full color image can be formed at a higher speed.

As the tandem type image forming apparatus, (1) as shown in FIG. 2, a conveying belt is provided so as to pass through a transfer position that is an area facing each electrostatic latent image carrier 1 of a plurality of image forming elements. A direct transfer system in which the visible image formed on each electrostatic latent image carrier 1 is sequentially transferred to the recording medium S moved by 3 by the transfer means 2, and (2) as shown in FIG. A visible image on each electrostatic latent image carrier 1 of a plurality of image forming elements is once transferred sequentially to an intermediate transfer member 4 by a transfer means (primary transfer means) 2, and then an image on the intermediate transfer member 4 is transferred to a second image. There is an indirect transfer method in which the next transfer means 5 performs batch transfer onto the recording medium S. In FIG. 3, a transfer conveyance belt is used as the secondary transfer unit, but a roller shape may be used.

Comparing the direct transfer method (1) and the indirect transfer method (2), the direct transfer method (1) is the tandem type image forming unit Td in which the electrostatic latent image carriers 1 are arranged. A sheet feeding device 6 must be disposed on the upstream side, and a fixing device 7 as a fixing unit must be disposed on the downstream side, which increases the size of the recording medium in the conveyance direction.
On the other hand, in the indirect transfer method of (2), the secondary transfer position can be set relatively freely, and the paper feeding device 6 and the fixing device 7 are arranged so as to overlap the tandem type image forming unit Td. There is an advantage that downsizing is possible.

In the direct transfer method (1), the fixing device 7 is disposed close to the tandem image forming unit Td so as not to increase in size in the recording medium conveyance direction. Therefore, the fixing device 7 cannot be disposed with a sufficient margin that the recording medium S can bend, and an impact when the leading end of the recording medium S enters the fixing device 7 (particularly with a thick recording medium). In addition, the fixing device 7 tends to affect upstream image formation due to the speed difference between the recording medium conveyance speed when passing through the fixing device 7 and the recording medium conveyance speed by the transfer conveyance belt.
On the other hand, in the indirect transfer method (2), the fixing device 7 can be disposed with a sufficient margin that the recording medium S can bend, so that the fixing device 7 hardly affects image formation.
In view of the above, in recent years, indirect transfer methods have attracted attention. In such a color image forming apparatus, as shown in FIG. 3, the transfer residual toner remaining on the electrostatic latent image carrier 1 after the primary transfer is removed by a cleaning device 8 as a cleaning unit, and the electrostatic latent image is thus removed. The surface of the carrier 1 is cleaned to prepare for the image formation again. Further, the transfer residual toner remaining on the intermediate transfer body 4 after the secondary transfer is removed by the intermediate transfer body cleaning device 9 to clean the surface of the intermediate transfer body 4 to prepare for image formation again.

The recording medium is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and can be appropriately selected according to the purpose. PET for OHP A base or the like can also be used.

(Fixing process and fixing means)
The fixing step is a step of fixing the visible image transferred to the recording medium, and may be performed each time the toner of each color is transferred to the recording medium, or a state where the toner is stacked on the toner of each color. Can be done at the same time.
The fixing step can be performed by a fixing unit.
The fixing unit is not particularly limited and may be appropriately selected depending on the intended purpose. However, a fixing unit having a fixing member and a heat source for heating the fixing member is preferable.

The fixing member is not particularly limited as long as it can contact each other to form a nip portion, and can be appropriately selected according to the purpose. For example, a combination of an endless belt and a roller, a roller and a roller, And the like. In particular, it is preferable to use a heating method from the surface of the fixing member by combining an endless belt and a roller, induction heating, or the like, in order to shorten the warm-up time and realize energy saving.

Examples of the fixing member include known heating and pressing means (combination of heating means and pressing means).
In the case of a combination of the endless belt and the roller, for example, a combination of a heating roller, a pressure roller, and an endless belt may be used as the heating and pressing unit, and the combination of the roller and the roller may be used. In this case, for example, a combination of a heating roller and a pressure roller can be used.

When the fixing member is an endless belt, the endless belt is preferably formed of a material having a small heat capacity. For example, an embodiment in which an offset prevention layer is provided on a substrate may be used.
Examples of the material forming the base include nickel and polyimide.
Examples of the material for forming the offset prevention layer include silicone rubber and fluorine-based resin.

When the fixing member is a roller, the cored bar of the roller is preferably formed of an inelastic member to prevent deformation (deflection) due to high pressure.
There is no restriction | limiting in particular as said inelastic member, Although it can select suitably according to the objective, High heat conductivity bodies, such as aluminum, iron, stainless steel, brass, are preferable.
Moreover, it is preferable that the surface of the roller is covered with an offset prevention layer.

The material for forming the offset prevention layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include RTV (Room Temperature Vulcanization) silicone rubber, tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), Examples thereof include polytetrafluoroethylene (PTFE).

In the fixing step, the image by the toner may be transferred to the recording medium, and the recording medium on which the image has been transferred may be passed through the nip portion to fix the image to the recording medium. The image may be transferred and fixed to the recording medium at the nip portion at the same time.

The fixing step may be performed each time the toner of each color is transferred to the recording medium, or may be performed at the same time in a state where the toner of each color is stacked.

The nip portion is formed by at least two fixing member components (for example, the endless belt and the roller, the roller and the roller) contacting each other.
The surface pressure of the nip portion is not particularly limited as long as it is a surface pressure that can break the capsule, and can be appropriately selected according to the purpose, preferably 1 MPa or more, more preferably 1 MPa to 5 MPa, 1 MPa to 2 MPa is particularly preferable. If the surface pressure of the nip portion is too high, the durability of the roller is lowered, and the fixing unit is increased in weight and size.

The temperature at which the toner image is fixed to the recording medium (that is, the surface temperature of the fixing member) is a temperature at which the effective temperature of the toner layer (toner transferred to the recording medium) is 40 ° C. to 50 ° C. Preferably, the fixing temperature is preferably 50 ° C. to 70 ° C., more preferably 50 ° C. to 60 ° C. in consideration of heat loss to an unfixed image carrier such as paper.
When a plasticizer that is solid at room temperature is used as the plasticizer, the fixing temperature is preferably a temperature at which the plasticizer in the toner in the fixing step is liquefied.

As the fixing means, (1) an aspect in which the fixing means has at least one of a roller and a belt, is heated from a surface not in contact with the toner, and the transferred image transferred onto the recording medium is fixed by heating and pressing. (Internal heating system) and (2) A fixing unit has at least one of a roller and a belt, and heats and presses a transfer image transferred onto a recording medium by heating from the surface in contact with the toner. (External heating method).
It is also possible to use a combination of both.

As the internal heating type fixing means (1), for example, the fixing member itself has a heating means inside. Examples of such heating means include a heat source such as a heater and a halogen lamp.

As the (2) external heating type fixing means, for example, at least a part of the surface of at least one of the fixing members is preferably heated by the heating means. There is no restriction | limiting in particular as such a heating means, According to the objective, it can select suitably, For example, an electromagnetic induction heating means etc. are mentioned.

There is no restriction | limiting in particular as said electromagnetic induction heating means, Although it can select suitably according to the objective, What has a means to generate | occur | produce a magnetic field and a means to generate heat | fever by electromagnetic induction, etc. are preferable.
The electromagnetic induction heating means includes, for example, an induction coil disposed so as to be close to the fixing member (for example, a heating roller), a shielding layer provided with the induction coil, and an induction coil of the shielding layer. What consists of an insulating layer provided in the other side of the provided surface is preferable. In this case, it is preferable that the heating roller is formed of a magnetic material or a heat pipe.
The induction coil is disposed in a state of wrapping at least a semi-cylindrical portion on the opposite side of the heating roller from the contact portion between the heating roller and the fixing member (for example, a pressure roller, an end belt). Is preferred.

(Internal heating type fixing means)
FIG. 4 is a belt-type fixing device showing an example of an internal heating type fixing means. The belt-type fixing device 510 in FIG. 4 includes a heating roller 511, a fixing roller 512, a fixing belt 513, and a pressure roller 514.
The fixing belt 513 is stretched by a heating roller 511 and a fixing roller 512 that are rotatably arranged inside, and is heated to a predetermined temperature by the heating roller 511. The heating roller 511 has a built-in heating source 515 and is designed so that the temperature can be adjusted by a temperature sensor 517 attached in the vicinity of the heating roller 511. The fixing roller 512 is rotatably disposed inside the fixing belt 513 and in contact with the inner surface of the fixing belt 513. The pressure roller 514 is in contact with the outer side of the fixing belt 513 and the outer surface of the fixing belt 513 so as to press the fixing roller 512 and is rotatably arranged.
Further, the surface hardness of the fixing belt 513 is lower than the surface hardness of the pressure roller 514, and the nip portion N formed between the fixing roller 512 and the pressure roller 514 has an introduction side end and a discharge side of the recording medium S. An intermediate region located between the ends is located closer to the fixing roller 512 than the introduction side end and the discharge side end.

In the belt-type fixing device 510 shown in FIG. 4, first, the recording medium S on which the toner image T to be fixed is formed is conveyed to the heating roller 511. The toner image T on the recording medium S is heated and melted by the heating roller 511 and the fixing belt 513 heated to a predetermined temperature by the action of the built-in heating source 515. In this state, the recording medium S is inserted into a nip portion N formed between the fixing roller 512 and the pressure roller 514. The recording medium S inserted into the nip N is brought into contact with the surface of the fixing belt 513 that rotates in conjunction with the rotation of the fixing roller 512 and the pressure roller 514 and is pressed when passing through the nip N. The toner image T is fixed on the recording medium S.
Next, the recording medium S on which the toner image T is fixed passes between the fixing roller 512 and the pressure roller 514, is peeled off from the fixing belt 513, and is conveyed to a tray (not shown). At this time, the recording medium S is discharged toward the pressure roller 514, and the winding of the recording medium S around the fixing belt 513 is prevented. The fixing belt 513 is cleaned by the cleaning roller 516.

(External heating type fixing means)
FIG. 5 shows an electromagnetic induction heating type fixing device 570 showing an example of an external heating type fixing means. The electromagnetic induction heating type fixing device 570 includes a heating roller 566, a fixing roller 580, a fixing belt 567, a pressure roller 590, and an electromagnetic induction heating unit 560.
The fixing belt 567 is stretched by a heating roller 566 and a fixing roller 580 that are rotatably arranged inside, and is heated to a predetermined temperature by the heating roller 566.
The heating roller 566 has, for example, a hollow cylindrical magnetic metal member such as iron, cobalt, nickel, or an alloy of these metals. For example, the outer diameter is 20 mm to 40 mm, and the wall thickness is 0.3 mm to 1.0 mm. It has a low heat capacity and quick temperature rise.

The fixing roller 580 has, for example, a metal core 581 made of stainless steel or the like, and the surface thereof is formed by covering a heat-resistant silicone rubber with a solid or foamed elastic layer 582. It is disposed inside the fixing belt 567 and rotatably while being in contact with the inner surface of the fixing belt 567. The fixing roller 580 is provided with an outer diameter of about 20 mm to 40 mm in order to form a nip portion N having a predetermined width between the pressure roller 590 and the fixing roller 580 by a pressing force from the pressure roller 590, and is heated. It is larger than the roller 566. The elastic layer 582 has a thickness of about 4 mm to 6 mm, and is formed such that the heat capacity of the heating roller 566 is smaller than the heat capacity of the fixing roller 580, thereby shortening the warm-up time of the heating roller 566.

The pressure roller 590 has a metal core 591 made of a cylindrical member made of a metal having high thermal conductivity such as copper or aluminum, and the surface thereof is covered with an elastic layer 592 having high heat resistance and high toner releasability. The fixing roller 580 is in contact with the outer surface of the fixing belt 567 and the outer surface of the fixing belt 567 so as to be in pressure contact with the fixing belt 567, and is rotatably disposed. In addition to the above metal, SUS may be used for the metal core 591.

The electromagnetic induction heating unit 560 is disposed in the vicinity of the heating roller 566 and in the axial direction of the heating roller 566. The electromagnetic induction heating unit 560 includes an excitation coil 561 that is a magnetic field generation unit, and a coil guide plate 562 around which the excitation coil 561 is wound. The coil guide plate 562 has a semi-cylindrical shape disposed close to the outer peripheral surface of the heating roller 566, and the exciting coil 561 is formed by passing a long exciting coil wire along the coil guide plate 562 in the axial direction of the heating roller 566. It is one that is wound around alternately. The exciting coil 561 is connected to a driving power source (not shown) whose frequency is variable. On the outside of the excitation coil 561, a semi-cylindrical excitation coil core 563 made of a ferromagnetic material such as ferrite is fixed to the excitation coil core support member 564 and is disposed close to the excitation coil 561.

(Fixing means using ultrasonic vibration application method)
In addition to the fixing unit using the heating and pressing unit described above, a fixing unit using ultrasonic vibration that is excellent in capsule destructibility can also be used. FIG. 6 shows a schematic diagram of one embodiment of the present invention. The fixing device 600 includes an ultrasonic vibration applying unit 601, an endless belt 602, and a pressing unit 603.

The ultrasonic vibration applying means includes at least an ultrasonic vibration source and an ultrasonic horn that transmits the ultrasonic vibration to the recording medium. An ultrasonic horn having a length corresponding to the width of the recording medium in the depth direction of the paper surface is used. The vibration frequency applied as the ultrasonic vibration is not particularly limited, and a frequency from 20 KHz to 1 MHz is preferable. If the frequency is 1 MHz or higher, the amplitude of the ultrasonic vibrator becomes small at that time, and the toner may not be fixed.

The endless belt sandwiches and carries the unfixed image together with the pressure roller and simultaneously conveys it. The endless belt includes a base, a rubber layer, and a surface layer. Although it does not specifically limit as a material which comprises a base | substrate, Nickel, a polyimide, etc. are mentioned. Although it does not specifically limit as a rubber layer, A silicone rubber, urethane rubber, etc. can be used. Although it does not specifically limit as a surface layer, Fluorine-type resins, such as PFA, can be used.

The pressure unit is not particularly limited, and examples thereof include a pressure roller and a pressure belt. In particular, a pressure roller that can easily obtain a sufficient pressing force is preferable. A metal roller such as aluminum or iron can be used as the pressure roller, and an elastic material such as silicon rubber or chloroprene rubber can be used around the metal roller surface. It is necessary to appropriately select the hardness and thickness of the material so that the ultrasonic vibration is not absorbed by the elastic material. Further, a heater may be provided in the pressure roller so that the toner image on the recording material can be heated.

(Light irradiation process and light irradiation means)
The light irradiation step is a step of polymerizing the plasticizer by irradiating light to the image after fixing and curing the resin, and can be suitably performed by a light irradiation means.
There is no restriction | limiting in particular as said light irradiation means, What is necessary is just to be able to irradiate light with respect to the image after fixing, and it can select suitably from well-known light irradiation means. The light to be irradiated is preferably ultraviolet light having a wavelength of about 290 to 400 nm. For example, a halogen lamp, UV-LED, etc. are mentioned suitably. Moreover, you may utilize the indoor lamp outside a machine, or natural light, without using these.

(Static elimination process and static elimination means)
The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrostatic latent image carrier, and can be suitably performed by a neutralization unit.
The neutralization means is not particularly limited, and may be appropriately selected from known neutralizers as long as it can apply a neutralization bias to the electrostatic latent image carrier. Preferably mentioned.

(Cleaning process and cleaning means)
The cleaning step is a step of removing the toner remaining on the electrostatic latent image carrier and can be suitably performed by a cleaning unit. In addition, it is also possible to employ a method in which the charge of the residual toner is made uniform by the rubbing member and collected by the developing roller without using the cleaning means.
The cleaning means is not particularly limited as long as it can remove the electrophotographic toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners. Suitable examples include brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, and web cleaners.

(Recycling process and recycling means)
The recycling step is a step of recycling the toner removed by the cleaning step to the developing unit, and can be suitably performed by the recycling unit. There is no restriction | limiting in particular as said recycling means, A well-known conveyance means etc. are mentioned.

(Control process and control means)
The control step is a step of controlling each of the steps, and can be suitably performed by a control unit.
The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as sequencers and computers.

The image forming apparatus is preferably an image forming apparatus including a process cartridge that integrally supports the electrostatic latent image carrier and at least the developing unit and is detachable from the image forming apparatus main body.

(Image forming apparatus and image forming method)
Next, one mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. An image forming apparatus 100 shown in FIG. 7 includes a photosensitive drum 10 as an electrostatic latent image carrier, a charging roller 20 as a charging unit, exposure L by an exposure unit as an exposure unit, and a developing unit as a developing unit. 40, an intermediate transfer member 50, a cleaning unit 60 as a cleaning unit, and a static elimination lamp 70 as a static elimination unit.

The intermediate transfer member 50 is an endless belt, and is designed so as to be movable in the direction of the arrow in the figure by three rollers 51 that are arranged on the inner side and stretch the belt. Part of the three rollers 51 also functions as a transfer bias roller that can apply a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. An intermediate transfer member cleaning device 90 is disposed in the vicinity of the intermediate transfer member 50, and a transfer bias for transferring a visible image (toner image) to the recording medium 95 (secondary transfer) is applied. Possible transfer rollers 80 as the transfer means are arranged to face each other. Around the intermediate transfer member 50, a corona charger 58 for applying a charge to the visible image on the intermediate transfer member 50 is connected to the electrostatic latent image carrier 10 in the rotation direction of the intermediate transfer member 50. The contact portion between the intermediate transfer member 50 and the contact portion between the intermediate transfer member 50 and the recording medium 95 is disposed.

The developing device 40 includes a developing belt 41 as a developer carrying member, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. Yes. The black developing unit 45K includes a developer accommodating portion 42K, a developer supply roller 43K, and a developing roller 44K. The yellow developing unit 45Y includes a developer container 42Y, a developer supply roller 43Y, and a developing roller 44Y. The magenta developing unit 45M includes a developer container 42M, a developer supply roller 43M, and a developing roller 44M. The cyan developing unit 45C includes a developer container 42C, a developer supply roller 43C, and a developing roller 44C. Further, the developing belt 41 is an endless belt, is rotatably stretched by a plurality of belt rollers, and a part thereof is in contact with the electrostatic latent image carrier 10.

In the image forming apparatus 100 shown in FIG. 7, first, the charging roller 20 uniformly charges the photosensitive drum 10. An exposure device (not shown) performs imagewise exposure L on the photosensitive drum 10 to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum 10 is developed by supplying toner from the developing device 40 to form a visible image. The visible image is transferred (primary transfer) onto the intermediate transfer member 50 by the voltage applied from the roller 51 and further transferred (secondary transfer) onto the recording medium 95. As a result, a transfer image is formed on the recording medium 95. The residual toner on the electrostatic latent image carrier 10 is removed by the cleaning blade 60, and the charge on the electrostatic latent image carrier 10 is once removed by the static elimination lamp 70.

Another mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The tandem type image forming apparatus shown in FIG. 8 is a tandem type color image forming apparatus. The tandem color image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center. The intermediate transfer member 50 is stretched around the support rollers 14, 15 and 16, and can be rotated clockwise in FIG. 8. In the vicinity of the support roller 15, an intermediate transfer member cleaning unit 17 for removing residual toner on the intermediate transfer member 50 is disposed. A tandem in which four image forming units 18 of yellow, cyan, magenta, and black are arranged to face each other on the intermediate transfer member 50 stretched between the support roller 14 and the support roller 15 along the conveyance direction. A mold developing means 120 is arranged. An exposure device 21 is disposed in the vicinity of the tandem developing unit 120. A secondary transfer unit 22 is disposed on the side of the intermediate transfer member 50 opposite to the side on which the tandem developing unit 120 is disposed. In the secondary transfer unit 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of rollers 23, and the recording medium conveyed on the secondary transfer belt 24 and the intermediate transfer member 50 are in contact with each other. Is possible. A fixing device 25 is disposed in the vicinity of the secondary transfer unit 22. The fixing device 25 includes a fixing belt 26 and a pressure roller 27.
In addition, a reversing device 28 for reversing the recording medium in order to form an image on both sides of the recording medium is disposed in the vicinity of the secondary transfer unit 22 and the fixing device 25.

Next, formation of a full-color image (color copy) using the tandem developing unit 120 will be described. That is, first, a document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and the document is set on the contact glass 32 of the scanner 300. 400 is closed.

When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. Immediately after that, the scanner 300 is driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, light from the light source is emitted from the first traveling body 33 and reflected light from the document surface is reflected by the mirror in the second traveling body 34 and is received by the reading sensor 36 through the imaging lens 35 to be color. A document (color image) is read and used as black, yellow, magenta, and cyan image information.

The image information of black, yellow, magenta, and cyan is stored in each image forming unit 18 (black image forming unit, yellow image forming unit, magenta image forming unit, and cyan image) in the tandem developing unit 120. Each of the image forming units forms black, yellow, magenta, and cyan toner images. That is, each image forming means 18 (black image forming means, yellow image forming means, magenta image forming means, and cyan image forming means) in the tandem developing means 120 is a static image as shown in FIG. An electrostatic latent image carrier 10 (black electrostatic latent image carrier 10K, yellow electrostatic latent image carrier 10Y, magenta electrostatic latent image carrier 10M, and cyan electrostatic latent image carrier 10C); The electrostatic latent image bearing member 10 is uniformly charged, and the electrostatic latent image bearing member is exposed (L in FIG. 9) for each color image corresponding to each color image information. An exposure device that forms an electrostatic latent image corresponding to each color image on the electrostatic latent image carrier, and each color toner (black toner, yellow toner, magenta toner, and cyan toner) Develop with A developing device 61 for forming a toner image with each color toner, a transfer charger 62 for transferring the toner image onto the intermediate transfer member 50, a cleaning device 63, and a charge eliminating device 64, respectively. Each single color image (black image, yellow image, magenta image, and cyan image) can be formed based on the image information of the colors. The black image, the yellow image, the magenta image, and the cyan image formed in this way are respectively transferred to the black electrostatic latent image carrier 10K on the intermediate transfer member 50 that is rotationally moved by the support rollers 14, 15, and 16. Black image formed on top, yellow image formed on electrostatic latent image carrier 10Y for yellow, magenta image formed on electrostatic latent image carrier 10M for magenta, and electrostatic latent image carrier for cyan The cyan image formed on 10C is sequentially transferred (primary transfer). Then, the black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer member 50 to form a composite color image (color transfer image).

On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed the recording medium from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the recording roller 142 is rotated to feed out the recording medium on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the recording medium. Then, the registration roller 49 is rotated in synchronization with the synthesized color image (color transfer image) synthesized on the intermediate transfer member 50, and the recording medium is sent between the intermediate transfer member 50 and the secondary transfer unit 22. Then, by transferring (secondary transfer) the composite color image (color transfer image) onto the recording medium by the secondary transfer means 22, a color image is transferred and formed on the recording medium. The residual toner on the intermediate transfer member 50 after image transfer is cleaned by the intermediate transfer member cleaning device 17.

The recording medium on which the color image has been transferred is conveyed by the secondary transfer means 22 and sent to the fixing device 25, where the combined color image (color transfer image) is generated by heat and pressure. ) Is fixed on the recording medium. After that, the recording medium is switched by the switching claw 55 and discharged by the discharge roller 56 and stacked on the paper discharge tray 57. Alternatively, the recording medium is switched by the switching claw 55 and reversed by the reversing device 28 and led again to the transfer position. After the image is also recorded on the back surface, the image is discharged by the discharge roller 56 and stacked on the discharge tray 57.

<Process cartridge>
The process cartridge of the present invention comprises at least an electrostatic image carrier, and developing means for developing a latent image formed on the electrostatic image carrier using the toner of the present invention to form a visible image. Are integrally formed.
The process cartridge further includes other means such as a charging unit, an exposure unit, a transfer unit, a cleaning unit, and a charge eliminating unit, which are appropriately selected as necessary.

The developing means includes at least a developer container that contains the toner or the developer, and a developer carrier that carries and transports the toner or developer contained in the developer container. In addition, a layer thickness regulating member for regulating the thickness of the toner layer carried on the developer carrying member may be provided. Specifically, any one of the one-component developing unit and the two-component developing unit described in the image forming apparatus and the image forming method can be preferably used.
Further, as the charging unit, the exposure unit, the transfer unit, the cleaning unit, and the charge eliminating unit, the same ones as those of the above-described image forming apparatus can be appropriately selected and used.
The process cartridge can be detachably provided in various electrophotographic image forming apparatuses, facsimile machines, and printers, and it is particularly preferable that the process cartridge is detachably provided in the image forming apparatus of the present invention.

Here, as shown in FIG. 10, for example, the process cartridge includes an electrostatic latent image carrier 101, and includes a charging unit 102, a developing unit 104, a transfer unit 108, and a cleaning unit 107, and further, if necessary. And other means. In FIG. 10, reference numeral 103 denotes exposure by exposure means, and 105 denotes a recording medium.
Next, the image forming process by the process cartridge shown in FIG. 10 will be described. The electrostatic latent image carrier 101 is rotated by the charging means 102 while being rotated in the direction of the arrow, and the exposure 103 by the exposure means (not shown). An electrostatic latent image corresponding to the exposure image is formed on the surface. The electrostatic latent image is developed by the developing unit 104, and the obtained visible image is transferred to the recording medium 105 by the transfer unit 108 and printed out. Next, the surface of the latent electrostatic image bearing member after the image transfer is cleaned by the cleaning unit 107, further neutralized by a neutralizing unit (not shown), and the above operation is repeated again.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

[Example 1]
<Preparation of capsule containing plasticizer>
In situ polymerization method includes dimethyl isophthalate (melting point: 69 ° C, Tokyo Kasei) as a plasticizer and paraffin wax (HNP11, melting point: 68 ° C, solubility in water: insoluble, Nippon Seiwa) as a poorly water-soluble substance. And the capsule whose shell is a melamine resin was produced as follows.

First, as an oil phase, 95 parts by mass of dimethyl isophthalate and 5 parts by mass of paraffin wax were heated to 80 ° C., mixed and dissolved.

Further, as a dispersant, 50 parts by mass of a styrene maleic anhydride copolymer (SMA 1000, Kawa crude oil), 183 parts by mass of ion-exchanged water, and 267 parts by mass of 2M sodium hydroxide aqueous solution (Kanto Chemical) were mixed, and the mixture was heated to 90 ° C. The mixture was heated and stirred for 12 hours to obtain a styrene maleic anhydride aqueous solution.
Furthermore, 1 part by mass of a silicone emulsion (E-20, Kao Chemical) was dissolved in 99 parts by mass of ion-exchanged water as an antifoaming material during emulsification to obtain an antifoaming material liquid.
Next, 60 parts by mass of the styrene maleic anhydride aqueous solution, 30 parts by mass of the defoaming material liquid, and 210 parts by mass of ion-exchanged water were mixed as an aqueous phase to obtain an aqueous phase.

20 parts by mass of the oil phase was mixed with 300 parts by mass of the aqueous phase, and pre-emulsified by stirring with heating using a stirrer while maintaining the temperature at 80 ° C. This emulsion was further treated with an ultrasonic homogenizer for 5 minutes to obtain an O / W emulsion in which fine oil droplets were dispersed.
In this emulsion, 30 parts by mass of methylol melamine (Nicaridine S305, Nippon Carbide) as a shell material was dissolved in 70 parts by mass of ion-exchanged water, and 21 parts by mass of a prepolymer solution filtered through a 0.45 μm syringe filter was added at a rate of 1 g / min. It was dripped at.
Further, 7.5 parts by mass of an aqueous citric acid solution in which 36 parts by mass of citric acid (Wako Pure Chemical Industries) was dissolved in 64 parts by mass of ion-exchanged water was added dropwise to the emulsion at a rate of 0.2 g / min. The emulsion was heated and stirred at 400 rpm for 4 hours while maintaining the temperature at 80 ° C. to finish the reaction and obtain a capsule dispersion.
This capsule dispersion was filtered and washed 5 times with ethanol and left to dry in the air for 12 hours to obtain a [plasticizer-encapsulated capsule].

When this capsule was cross-sectional observed with SEM / FIB, it was a capsule having a core-shell structure. Further, the capsule was re-dispersed in water and the particle size was measured using a zeta potential / particle size measuring device ELSZ-2 manufactured by Otsuka Electronics Co., Ltd. The average particle size was 410 nm.
Furthermore, when the encapsulation rate of the core agent was measured using a differential thermothermal gravimetric simultaneous measurement apparatus EXSTAR TG / DTA7200 manufactured by SII Nanotechnology, the encapsulation rate was 69% by mass.
Further, when the melting point of the core agent was measured using a high-sensitivity differential scanning calorimeter EXSTAR X-DSC7000 manufactured by SII Nanotechnology, a melting peak was confirmed at 63 ° C.

<Production of toner>
(Synthesis of resin fine particle emulsion)
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of a sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 139 parts of styrene, 138 parts of methacrylic acid, When 110 parts of butyl acrylate, 12 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion was obtained. This is designated as [fine particle dispersion]. The volume average particle size of the [fine particle dispersion] measured with a laser diffraction particle size distribution analyzer (LA-920, manufactured by Shimadzu Corp.) was 30 nm. A part of the [fine particle dispersion] was dried to isolate the resin component. The Tg of the resin was 42 ° C., and the weight average molecular weight was 30,000.

(Adjustment of aqueous phase)
990 parts of water, 30 parts of [fine particle dispersion], 37 parts of a 48.5% aqueous solution of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7 manufactured by Sanyo Chemical Industries), and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is referred to as [aqueous phase].

(Synthesis of non-reactive resin)
In a reaction vessel equipped with a condenser, stirrer and nitrogen inlet tube, 218 parts bisphenol A ethylene oxide 2-mole adduct, 537 parts bisphenol A propylene oxide 3-mole adduct, 213 parts terephthalic acid, 47 parts adipic acid and dibutyl Add 2 parts of tin oxide, react for 5 hours at 230 ° C. under normal pressure, and further react for 5 hours under reduced pressure of 10 to 15 mmHg. By reacting for a period of time, polyester [non-reactive resin A] was obtained.
[Nonreactive Resin A] had a number average molecular weight of 2500, a weight average molecular weight of 6700, Tg of 44 ° C., and an acid value of 24.

(Synthesis of intermediate polyester)
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at normal pressure and 230 ° C. for 8 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain an [intermediate polyester]. [Intermediate polyester] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, a Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.

(Prepolymer synthesis)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 410 parts of the above [intermediate polyester], 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate are added and reacted at 100 ° C. for 5 hours, and [prepolymer] is added. Obtained.
The weight percentage of free isocyanate in [Prepolymer] was 1.53%.

(Synthesis of ketimine)
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound]. The amine value of [ketimine compound] was 418.

(Production of master batch)
40 parts of carbon black (manufactured by Cabot, Regal 400R), 60 parts of [Non-Reactive Resin A] and 30 parts of water are added and mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). After kneading at 150 ° C. for 30 minutes, the product was cooled and rolled and pulverized with a pulverizer to obtain a [masterbatch].

(Production of oil phase)
In a container equipped with a stir bar and a thermometer, 400 parts of [Non-reactive resin A], 90 parts of carnauba wax, and 947 parts of ethyl acetate are charged, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. After that, it was cooled to 30 ° C. at 1 hour. Next, 500 parts of [Masterbatch], 110 parts of hydrophobic silica R972 (manufactured by Nippon Aerosil Co., Ltd.), 550 parts of [Plasticizer-encapsulated capsules], and 500 parts of ethyl acetate are charged into a container and mixed for 1 hour to obtain a [raw material solution]. It was.
1324 parts of the above [raw material solution] was transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were 80% by volume. The wax was dispersed under the conditions of filling and 3 passes.
Next, 1324 parts of 55% ethyl acetate solution of [Non-Reactive Resin A] was added, and one pass was performed with a bead mill under the above conditions to obtain [Pigment / Wax / Capsule Dispersion].
The [pigment / wax / capsule dispersion] had a solid content (130 ° C., 30 minutes) of 50%.

(Emulsification)
[Pigment / wax / capsule dispersion] 749 parts, [Prepolymer] 115 parts, [Ketimine compound] 2.9 parts in a container and mixed for 1 minute at 5,000 rpm with a TK homomixer (manufactured by Tokushu Kika) After that, 1200 parts of [Aqueous Phase] was added to the container and mixed with a TK homomixer at a rotation speed of 13,000 rpm for 20 minutes to obtain [Emulsified Slurry].
[Emulsion slurry] is put into a container in which a stirrer with a vertical blade and a thermometer are set, and aged for 90 minutes at 200 rpm and 28 ° C., and then desolvated at 30 ° C. for 8 hours. ] Was obtained.
The emulsification conditions are as follows. Total liquid feeding amount: 10 kg / min. Hold-up amount: 20L. Emulsifier shear rate: 17 m / sec. Emulsification temperature: 20 ° C. Furthermore, in the reservoir, stirring was carried out for 2 hours at 30 ° C. under an atmospheric pressure (101.3 kPa) at an outer peripheral edge peripheral speed of 10.5 m / sec.

(Solvent removal / cleaning)
The solvent removal step was performed by the following method. That is, the temperature was raised to 45 ° C., and the solvent was removed under an atmospheric pressure (101.3 kPa) at an outer peripheral end peripheral speed of 10.5 m / sec. The solvent removal time required 8 hours. Thereafter, after filtration, washing and drying, toner base particles were obtained.

(External processing)
Next, 100 parts of the obtained base particles and 0.3 part of a charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blades was adjusted to 50 m / Set to sec, 5 cycles were performed for 2 minutes of operation and 1 minute of rest, and the total processing time was 10 minutes.
Furthermore, 1.0 part of hydrophobic silica (H2000, manufactured by Clariant Japan Co., Ltd.) was added with a Henschel mixer, the peripheral speed was 15 m / sec, mixing for 30 seconds and resting for 1 minute was performed for 5 cycles. Coarse particles were removed with a screen having a mesh opening of 37 μm to obtain a toner of Example 1.

(Measurement of Tg)
The obtained toner was subjected to Tg measurement as follows. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used.
First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace.
First, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the temperature rising rate was again increased to 150 ° C. under a nitrogen atmosphere. DSC measurement was performed by heating at min. Tg was calculated from the contact point between the tangent line of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system. The Tg of the toner was 45.1 ° C.

(Measurement of average particle size)
The average particle diameter of the obtained toner was measured using a Coulter Counter TA-II (manufactured by Coulter), connected to an interface (manufactured by Nikka Giken) that outputs number distribution and volume distribution, and a PC 9801 personal computer (manufactured by NEC). did. The average particle size of the toner was 5.6 um.

[Evaluation]
The toner of Example 1 was evaluated by the following method. The results are shown in Table 1.

(Development agitation test)
The development agitation test was carried out using a modified machine of Ricoh's MFPimagegio MPC3000. Specifically, the toner was continuously stirred in the developing machine for 24 hours, and it was confirmed whether toner filming or toner spent occurred in the developing sleeve after 12 hours and after 24 hours.
<Result>
Even after 24 hours, neither toner filming nor toner spent in the developing sleeve was observed, and it was confirmed that the toner of Example 1 was excellent in toner filming resistance and toner spent resistance.

(Fixability test)
Using paper (Mypaper, manufactured by Ricoh Co., Ltd.), fixing was performed using a modified machine of Ricoh's MFPimage MPC3000. The fixing roller surface temperature is set to 90 ° C., the nip pressure is set to 1.0 MPa, and the recording paper on which an unfixed image is formed is passed at a nip width of 3 mm and a linear speed of 100 mm / s. The toner surface was rubbed with a waste cloth, and the stain condition of the waste was measured with a reflection densitometer (X-rite 939, manufactured by X-rite) to evaluate the fixability.

<Result>
No disturbance was observed in the fixed image, and no stain was observed on the waste rubbing the toner surface, and the toner of Example 1 was able to be fixed satisfactorily.

[Example 2]
Capsules and toners were obtained in the same manner as in Example 1, except that the plasticizer was changed to diphenyl carbonate (melting point: 80 ° C., Tokyo Kasei).
The obtained capsule had a core-shell structure, and the average particle diameter was 400 nm, the encapsulation rate was 70%, and the melting point of the core material was confirmed to have two melting peaks of 63 ° C. and 75 ° C. The average particle size of the toner was 5.3 μm.

(Development agitation test)
When a development agitation test was conducted in the same manner as in Example 1, no toner filming or toner spent in the developing sleeve was observed even after 24 hours, and the toner of Example 2 was resistant to toner filming. It was confirmed that the toner spent resistance was excellent.

(Fixability test)
When the fixability test was performed in the same manner as in Example 1, no irregularity was observed in the fixed image, and no dirt was seen on the waste that rubbed the toner surface, and the toner of Example 2 could be fixed satisfactorily. It was.

[Example 3]
In Example 1, the soft water-soluble substance was changed to docosyl docosylate (melting point 70 ° C., solubility in water: insoluble, Wako Pure Chemical Industries), and the ratio of the plasticizer and the hardly water-soluble substance was changed to 90:10. Capsules and toners were obtained in the same manner as in Example 1.
The obtained capsule had a core-shell structure, and an average particle diameter was 350 nm, the inclusion rate was 70%, and the melting point of the core material was confirmed to be 63 ° C. The average particle size of the toner was 5.2 um.

(Development agitation test)
When a development agitation test was conducted in the same manner as in Example 1, no toner filming or toner spent in the developing sleeve was observed even after 24 hours, and the toner of Example 3 was resistant to toner filming. It was confirmed that the toner spent resistance was excellent.

(Fixability test)
When the fixability test was performed in the same manner as in Example 1, no irregularity was observed in the fixed image, and no dirt was seen on the waste that rubbed the toner surface, and the toner of Example 3 could be fixed satisfactorily. It was.

[Example 4]
In Example 3, capsules and toners were obtained in the same manner as in Example 3 except that the plasticizer was changed to diphenyl carbonate.
The obtained capsule had a core-shell structure, and the average particle diameter was 350 nm, the encapsulation rate was 73%, and the melting point of the core material was confirmed to have two melting peaks of 64 ° C. and 75 ° C. The average particle size of the toner was 5.4 um.

(Development agitation test)
When a development agitation test was conducted in the same manner as in Example 1, no toner filming or toner spent in the developing sleeve was observed even after 24 hours, and the toner of Example 4 was resistant to toner filming. It was confirmed that the toner spent resistance was excellent.

(Fixability test)
When the fixability test was performed in the same manner as in Example 1, no irregularity was observed in the fixed image, and no dirt was observed on the waste that rubbed the toner surface, and the toner of Example 4 could be fixed well. It was.

[Example 5]
Capsules and toners were obtained in the same manner as in Example 1 except that the slightly water-soluble substance was changed to dicyclohexyl phthalate (melting point: 65 ° C., water solubility: 0.94 g / L, Tokyo Kasei). It was.
The obtained capsule had a core-shell structure, and an average particle diameter was 510 nm, an encapsulation rate was 71%, and a melting peak of the core material was confirmed at 54 ° C.
The average particle size of the toner was 5.6 um.

(Development agitation test)
When a development agitation test was conducted in the same manner as in Example 1, no toner filming or toner spent in the developing sleeve was observed after 12 hours, and a slight amount of toner in the sleeve was observed after 24 hours. Although it was confirmed that the image was fixed, the image output was not affected. It was confirmed that the toner of Example 5 can withstand toner filming and toner spent in the developing machine.

(Fixability test)
When the fixability test was performed in the same manner as in Example 1, no irregularity was observed in the fixed image, and no dirt was observed on the waste that rubbed the toner surface, and the toner of Example 5 could be fixed satisfactorily. It was.

[Example 6]
In Example 1, capsules and toners were prepared in the same manner as in Example 1 except that the hardly water-soluble substance was changed to a styrene maleic anhydride copolymer (SMA 1000, Tg 155 ° C., water solubility: insoluble, river crude). Got.
The obtained capsule had a core-shell structure. The average particle size was 830 nm, the encapsulation rate was 77%, and the melting point of the core material was confirmed to be 62 ° C. In the toner production process, the plasticizer capsule was partly detached from the toner. The average particle size of the toner was 6.7 um.

(Development agitation test)
When a development agitation test was conducted in the same manner as in Example 1, no toner filming or toner spent in the developing sleeve was observed, and the toner of Example 6 was resistant to toner filming and toner spent. It was confirmed that it was excellent.

(Fixability test)
A fixing test was conducted in the same manner as in Example 1. As a result, although the image was not disturbed, the waste that rubbed the toner surface was slightly stained, and the toner of Example 6 was fixed at low temperature. Although possible, the fixability was not good.

[Comparative Example 1]
Capsules and toners were obtained in the same manner as in Example 1, except that the poorly water-soluble substance was changed to hexadecane (melting point: 18 ° C., water solubility: insoluble, Kanto Chemical).
The obtained capsule had a core-shell structure, and it was confirmed that the average particle diameter was 430 nm, the encapsulation rate was 68%, and the melting point of the core material was two melting peaks of 14 ° C. and 63 ° C. The average particle size of the toner was 4.9 um.

(Development agitation test)
When a development agitating test was performed in the same manner as in Example 1, abnormal noise was generated in one hour from the start of the test, and the toner was fixed in the developing sleeve. The toner of Comparative Example 1 was resistant to toner filming. And inferior toner spent resistance were confirmed.

[Comparative Example 2]
In Example 1, capsules and toners were obtained in the same manner as in Example 1 except that 2 ′, 4′-dimethoxyacetophenone (melting point: 40 ° C., Tokyo Kasei) was used as the plasticizer.
The obtained capsule had a core-shell structure, and it was confirmed that the average particle size was 380 μm, the encapsulation rate was 63%, and the melting point of the core material was 34 ° C. The average particle size of the toner was 4.9 μm.

(Development agitation test)
When the development agitation test was performed in the same manner as in Example 1, an abnormal noise was generated 30 minutes after the start of the test, and the toner was fixed in the development sleeve. The toner of Comparative Example 2 was resistant to toner filming. And inferior toner spent resistance were confirmed.

[Comparative Example 3]
In Example 1, capsules were obtained in the same manner as in Example 1 except that the hardly water-soluble substance was not used.
The obtained capsule had a core-shell structure, and it was confirmed that the average particle size was 4 μm, the encapsulation rate was 70%, and the melting point of the core material was 63 ° C. The capsule particle size was too large to be converted into toner. In Comparative Example 3, it was confirmed that a capsule having a small particle size that could be dispersed inside the toner particles could not be obtained.

The physical properties of the capsule are shown in Table 1, and the above results are shown in Table 2.

表２中の評価基準は以下のとおりである。
なお、現像アジテート試験における「−」は、トナー化ができないため、定着試験における「−」は、現像アジテート試験が不十分であったために、評価を行わなかったことを表す。

The evaluation criteria in Table 2 are as follows.
Note that “−” in the development agitation test cannot be converted to toner, and “−” in the fixing test indicates that the evaluation was not performed because the development agitation test was insufficient.

<Development agitation test>
○: Excellent toner filming resistance and toner spent resistance △: Toner filming resistance and toner spent resistance are within acceptable ranges ×: Insufficient toner filming resistance and toner spent resistance

<Fixability test>
○: Good low-temperature fixability △: Possible to fix at low temperature ×: Insufficient low-temperature fixability

From the above results, the toner of the present invention was excellent in low-temperature fixability and excellent in toner spent resistance and toner filming resistance.

1 Electrostatic latent image carrier (photosensitive drum)
2 Transfer means (primary transfer means)
3 Conveying belt 4 Intermediate transfer member 5 Secondary transfer means 6 Paper feeding device 7 Fixing device 8 Cleaning device 9 Intermediate transfer member cleaning device 10 Electrostatic latent image carrier (photosensitive drum)
10K Black electrostatic latent image carrier 10Y Yellow electrostatic latent image carrier 10M Magenta electrostatic latent image carrier 10C Cyan electrostatic latent image carrier 14 Support roller 15 Support roller 16 Support roller 17 Intermediate transfer cleaning means 18 Image forming means 20 Charging roller 21 Exposure device 22 Secondary transfer means 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Reversing device 30 Exposure device 32 Contact glass 33 First traveling body 34 Second traveling Body 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing belt 42K Developer container 42Y Developer container 42M Developer container 42C Developer container 43K Developer supply roller 43Y Developer supply roller 43M Developer supply roller 43C Developer supply roller 44K Development roller 44Y Development roller 44M Image roller 44C Developing roller 45K Black developing means 45Y Yellow developing means 45M Magenta developing means 45C Cyan developing means 49 Registration roller 50 Intermediate transfer member 51 Roller 52 Separating roller 53 Manual feed path 54 Manual feed tray 55 Switching claw 56 Discharge Roller 57 Discharge tray 58 Corona charger 60 Cleaning means 61 Developing device 62 Transfer charger 63 Cleaning device 64 Static elimination device 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Recording medium 100 Image forming apparatus 101 Electrostatic latent image carrier 102 Charging means 103 exposure means 104 developing means 105 recording medium 107 cleaning means 108 transfer means 120 tandem developing means 130 document table 142 paper feed roller 143 paper bank 144 paper feed cassette 145 separation roller 146 Paper path 147 transport rollers 148 feed path 150 copying apparatus main body 160 a charging device 200 feeder table 201 toner 202 binder resin 203 colorant 204 capsules 205 charge controlling agent 206 external additive 300 Scanner 400 automatic document feeder (ADF)
510 Belt-type fixing device 511 Heating roller 512 Fixing roller 513 Fixing belt 514 Pressure roller 515 Heating source 516 Cleaning roller 517 Temperature sensor 561 Excitation coil 562 Coil guide plate 563 Excitation coil core support member 560 Electromagnetic induction heating means 566 Heating roller 567 Fixing belt 570 Electromagnetic induction heating type fixing device 580 Fixing roller 581 Core metal 582 Elastic layer 590 Pressure roller 591 Core metal 592 Elastic layer 600 Fixing device 601 of ultrasonic vibration application system Ultrasonic vibration applying means 602 Endless belt 603 Pressing Means 604 to 607 Roller 608 for passing the endless belt Toner image 609 Recording material S Recording medium T Toner image N Nip part Td Tandem type image forming part

Japanese Patent No. 5022308 JP 2012-1117021 A JP 2011-74356 A JP 2008-56828 A JP 2013-7996 A

Claims (6)

A toner containing at least a binder resin and a capsule, wherein the capsule includes a core material containing at least a plasticizer that softens the binder resin and a hardly water-soluble substance, and a shell material is softened by the plasticizer. The toner is characterized by being destroyed when a pressure equal to or higher than a predetermined pressure is applied, and the plasticizer and the hardly water-soluble substance have a melting point exceeding 60 ° C. The toner according to claim 1, wherein the plasticizer and the hardly water-soluble substance do not form a solid solution. The toner according to claim 1, wherein the poorly water-soluble substance is a wax. A developer comprising the toner according to claim 1. An electrostatic latent image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and developing the electrostatic latent image with toner to form a visible image A developing unit that transfers the visible image onto a recording medium; and a fixing unit that fixes the transferred image transferred onto the recording medium, wherein the toner is any one of claims 1 to 3. An image forming apparatus comprising the toner according to claim 1. An electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image carrier, a developing step of developing the electrostatic latent image with toner to form a visible image, and the visible image And a fixing step of fixing the transferred image transferred to the recording medium, wherein the toner is the toner according to claim 1. Image forming method.

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