JP4523573B2 - Toner and image forming apparatus - Google Patents

Description

  The present invention relates to a toner for developing an electrostatic charge image and an image forming apparatus using the toner in a copying machine, electrostatic printing, a printer, a facsimile, electrostatic recording, and the like.

  In the development process, the developer used in electrophotography, electrostatic recording, electrostatic printing, and the like is once attached to an image carrier such as an electrostatic latent image carrier on which an electrostatic charge image is formed, In the transfer step, the image is transferred from the electrostatic latent image carrier onto a transfer medium such as transfer paper, and then fixed on the paper surface in the fixing step. At that time, as a developer for developing the electrostatic image formed on the latent image holding surface, a two-component developer composed of a carrier and a toner, and a one-component developer that does not require a carrier (magnetic toner). Non-magnetic toner) is known.

  The toner used for the developer is required to have excellent low-temperature fixability and storage stability (blocking resistance) with the development of electrophotographic technology, and styrene which has been generally used as a binder resin for toner. Attempts have been made to use a polyester resin that has a higher affinity with a recording medium or the like than a resin and has excellent low-temperature fixability. For example, a toner containing a linear polyester resin that defines physical properties such as molecular weight (see Patent Document 1), a toner containing a non-linear cross-linked polyester resin using rosins as an acid component (see Patent Document 2), etc. Has been proposed.

However, due to the further increase in speed and energy saving of recent image forming apparatuses, it has been found that conventional binder resins for toner are insufficient for market demand. That is, it is very difficult to maintain a sufficient fixing strength due to shortening of the fixing time in the fixing process and lowering of the heating temperature by the fixing means.
On the other hand, the toner containing a polyester resin using a rosin as described in Patent Document 2 is excellent in low-temperature fixability and has an advantage that the toner productivity in the pulverization method can be improved because of excellent pulverization properties. There is a problem that odor is likely to occur during fixing.

On the other hand, for low-temperature fixing, it is effective to lower the melt viscosity of the toner. However, since such toner tends to cause hot offset, a release oil such as silicone oil is applied to a hot roll or the like. To be done.
However, the method of applying the release oil requires an oil tank or an oil application device, which makes the device complicated and large. In addition, oil adheres to copy paper, OHP (overhead projector) film, and the like, and there are problems such as writing performance with water-based ink and deterioration of color tone due to oil deposited on OHP.
Therefore, in order to prevent hot offset without applying release oil, a method of adding a release agent such as wax to the toner is generally used. At this time, the state of dispersion in the toner greatly affects the release effect of the release agent. Specifically, when the release agent is compatible with the binder, the release property cannot be expressed, it exists as incompatible domain particles, and the release property exudes to the toner surface during fixing. It can be demonstrated.

However, if the dispersion diameter of the release agent is too large, the proportion of wax present in the vicinity of the toner particle surface is relatively increased, so that agglomeration is exhibited and fluidity is deteriorated or externally added to the toner surface. Additives are embedded to deteriorate transferability and developability, resulting in a decrease in image density, and, when used for a long period of time, wax migrates to the surface of the photoreceptor, causing filming and obtaining good image quality. The problem of obstructing may arise.
In order to solve this problem, in Patent Documents 3 to 8 below, it has been proposed to use a resin obtained by grafting a styrene resin to a polyolefin resin together with a release agent, but low temperature fixability, offset resistance, and No results satisfying filming resistance at the same time have been obtained.

JP 2004-245854 A JP-A-4-70765 Japanese Patent Laid-Open No. 52-3304 Japanese Patent Publication No. 7-82255 JP 2000-75549 A JP 2001-249485 A Japanese Patent Laid-Open No. 2003-202698 JP 2003-255589 A

  An object of the present invention is to solve various problems in the prior art and achieve the following objects. That is, the present invention is excellent in low-temperature fixability and anti-offset properties, does not cause filming on the photoreceptor, has a stable image density against changes in image area and image output conditions, and can be used for a long time. An object of the present invention is to provide a toner and an image forming apparatus that can form a high-quality image and that does not generate odor during fixing.

Means for solving the problems are as follows. That is,
<1> and a binder resin, a colorant, poly olefin wax, and a release agent comprising at least one long-chain hydrocarbon waxes, polyethylene, polymethylene, polypropylene, ethylene / propylene copolymer and the thermal degradation products The main chain is at least one type of polyolefin resin selected from any of the above, and at least one type selected from styrene, alkyl (meth) acrylate, and (meth) acrylonitrile, and the SP value is a graft polymer grafted with vinyl resin is 10.0 to 11.5, containing,
The binder resin comprises an alcohol component of either an aliphatic dialcohol or an alkylene oxide adduct of bisphenol A, a purified rosin purified by distillation, an aliphatic dicarboxylic acid or anhydride thereof, an aromatic dicarboxylic acid or anhydrides, alicyclic dicarboxylic acids or their anhydrides, trivalent or higher polycarboxylic acid or its anhydride, and condensed with at least one, the the number of carbon atoms is selected from any of 1 to 3 alkyl esters Contains a polyester resin obtained by polymerization,
Wherein of the polyester resin 100 parts by weight, the graft polymer 2.0 parts by mass to 10 parts by mass seen including,
10 to 150 parts by mass of the graft polymer is included with respect to 100 parts by mass of the release agent.
The toner is characterized by the above.
<2> The toner according to <1>, wherein the alcohol component contains 1,2-propanediol in an amount of 65 mol% or more in the divalent alcohol component.
<3> The polyester resin includes a polyester resin (A) having a softening point Tm (A) of 120 ° C. or higher and 160 ° C. or lower, and a polyester resin (B) having a softening point Tm (B) of 80 ° C. or higher and lower than 120 ° C. The toner according to any one of <1> to <2>.
<4> The toner according to any one of <1> to <3>, wherein the purified rosin is modified with at least one of acrylic acid, fumaric acid, and maleic acid.
<5> The toner according to any one of <1> to <4>, wherein the polyolefin resin has a softening point of 70 to 150 ° C.

< 6 > An electrostatic latent image carrier, electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, and the electrostatic latent image of <1> to < 5 > Developing means for developing a visible image by developing using any of the toners, Transfer means for transferring the visible image to a recording medium, and Fixing means for fixing the transferred image transferred to the recording medium And an image forming apparatus characterized by comprising:

The toner of the present invention contains a binder resin, a colorant, a release agent, and a graft polymer composed of at least a polyolefin resin and a vinyl resin,
The binder resin contains a polyester resin obtained by condensation polymerization of an alcohol component and a carboxylic acid component containing rosin. At this time, since purified rosin was used as the rosin, it was excellent in low-temperature fixability and anti-offset properties, did not cause filming on the photoreceptor, and could form a high-quality image over a long period of time. Furthermore, no odor is generated during fixing.

The image forming apparatus of the present invention includes an electrostatic latent image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier, and the electrostatic latent image as a toner of the present invention. And developing means for forming a visible image by developing the 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.
Since the toner of the present invention is used in this way, a toner that is excellent in low-temperature fixability and anti-offset property, does not cause filming on the photoreceptor, and can reduce odor generation is obtained. Therefore, it is possible to form an extremely high quality image having excellent fixability, no color tone change over a long period of use, and no abnormal images such as density reduction and background stains.

  According to the present invention, conventional problems can be solved, excellent low-temperature fixability and anti-offset properties, no filming on the photoconductor, and no change in image area or image output conditions. It is possible to provide a toner and an image forming apparatus that have a stable density, can form a high-quality image over a long period of time, and do not generate odor during fixing.

(toner)
The toner of the present invention contains a binder resin, a colorant, a release agent, and a graft polymer, and further contains other components as necessary. The binder resin includes an alcohol component. And a polyester resin obtained by condensation polymerization of a carboxylic acid component containing purified rosin.

  In the toner of the present invention, by containing the purified rosin in the polyester resin, fixing at an extremely low temperature is possible, and the storability is improved and the odor is reduced. The reason why the odor is reduced and the storage stability is improved in this way is considered to be because impurities are reduced by purification. In addition, it is speculated that the crystallization of rosin is promoted by purification.

-Binder resin-
The binder resin includes a polyester resin obtained by condensation polymerization of an alcohol component and a carboxylic acid component containing purified rosin.

--Carboxylic acid component--
The carboxylic acid component contains purified rosin. The rosin in the purified rosin is a natural resin obtained from pine, the main component of which is a resin such as abietic acid, neoabietic acid, parastrinic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, dehydroabietic acid Acids and mixtures thereof.
The rosin is roughly classified into tall rosin obtained from tall oil obtained as a by-product in the process of producing pulp, gum rosin obtained from raw pine ani, wood rosin obtained from pine stumps, etc., as the purified rosin in the present invention From the viewpoint of low-temperature fixability, purified tall rosin is preferable.
In addition, a purified product of a modified rosin such as a disproportionated rosin or a hydrogenated rosin can also be used. It is preferable to do.

The purified rosin is rosin in which impurities are reduced by a purification process. By purifying rosin in this way, impurities contained in rosin are removed. Examples of main impurities include 2-methylpropane, acetaldehyde, 3-methyl-2-butanone, 2-methylpropanoic acid, butanoic acid, pentanoic acid, n-hexanal, octane, hexanoic acid, benzaldehyde, 2-pentylfuran, Examples include 2,6-dimethylcyclohexanone, 1-methyl-2- (1-methylethyl) benzene, 3,5-dimethyl-2-cyclohexene, 4- (1-methylethyl) benzaldehyde and the like. Among these, the peak intensity of three types of impurities, hexanoic acid, pentanoic acid, and benzaldehyde, detected as a volatile component by the headspace GC-MS method, can be used as an indicator of purified rosin. The reason why the volatile component rather than the absolute amount of impurities is used as an indicator is that the use of the purified rosin in the present invention makes the odor one of the problems of improvement over the conventional polyester using the rosin.
Specifically, the purified rosin means that the hexanoic acid peak intensity is 0.8 × 10 ⁷ or less and the pentanoic acid peak intensity is 0 under the measurement conditions of the headspace GC-MS method of Examples described later. .4 × is 10 ⁷ or less, a peak intensity of benzaldehyde refers to rosin is 0.4 × 10 ⁷ or less. Furthermore, from the viewpoint of storage stability and odor, the peak intensity of hexanoic acid is preferably 0.6 × 10 ⁷ or less, and more preferably 0.5 × 10 ⁷ or less. The peak intensity of pentanoic acid is preferably 0.3 × 10 ⁷ or less, and more preferably 0.2 × 10 ⁷ or less. The peak intensity of benzaldehyde is preferably 0.3 × 10 ⁷ or less, and more preferably 0.2 × 10 ⁷ or less.
Furthermore, from the viewpoint of storage stability and odor, it is preferable that n-hexanal and 2-pentylfuran are reduced in addition to the above three types of substances. The peak intensity of n-hexanal is preferably 1.7 × 10 ⁷ or less, more preferably 1.6 × 10 ⁷ or less, and particularly preferably 1.5 × 10 ⁷ or less. The peak intensity of 2-pentylfuran is preferably 1.0 × 10 ⁷ or less, more preferably 0.9 × 10 ⁷ or less, and particularly preferably 0.8 × 10 ⁷ or less.

  The method for purifying the rosin is not particularly limited, and a known method can be used. Examples thereof include distillation, recrystallization, extraction, and the like, and purification by distillation is preferable. As the distillation method, for example, the method described in JP-A-7-286139 can be used, and examples thereof include vacuum distillation, molecular distillation, steam distillation, etc., but purification by vacuum distillation is preferable. For example, distillation is usually carried out at a still temperature of 200 to 300 ° C. at a pressure of 6.67 kPa or less, and methods such as ordinary simple distillation, thin film distillation, rectification and the like are applied. Under normal distillation conditions, 2 to 10% by mass of a high molecular weight product is removed as a pitch component with respect to the charged rosin, and at the same time, 2 to 10% by mass of an initial fraction is simultaneously removed.

  The softening point of the purified rosin is preferably 50 to 100 ° C, more preferably 60 to 90 ° C, and particularly preferably 65 to 85 ° C. The softening point of the rosin is a softening point measured when the rosin is once melted and naturally cooled for one hour in an environment of a temperature of 25 ° C. and a relative humidity of 50% by the measurement method shown in the examples described later. means.

The acid value of the purified rosin is preferably 100 to 200 mgKOH / g, more preferably 130 to 180 mgKOH / g, and particularly preferably 150 to 170 mgKOH / g.
The acid value of the purified rosin can be measured based on, for example, the method described in JIS K0070.

  When a modified rosin is used as the purified rosin, an acid having an unsaturated double bond is added to the purified rosin under heating from the viewpoint of enhancing hot offset property and storage stability. It is preferable to add by reaction to increase the molecular weight and glass transition point of the polyester. As the acid having an unsaturated double bond, (meth) acrylic acid, fumaric acid, and maleic acid are preferably used from the viewpoint of reactivity.

  The content of the purified rosin or modified rosin is preferably 2 to 50 mol%, more preferably 5 to 40 mol%, and particularly preferably 10 to 30 mol% in the carboxylic acid component.

  The carboxylic acid compound may further contain a carboxylic acid compound other than the purified rosin. The carboxylic acid compound is not particularly limited and may be appropriately selected depending on the intended purpose.For example, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, Aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, n-dodecyl succinic acid and n-dodecenyl succinic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid; alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid Acids: Trivalent or higher polyvalent carboxylic acids such as trimellitic acid and pyrrolemetic acid; or anhydrides and alkyl (C1 to C3) esters of these acids. In the present specification, such acids, anhydrides of these acids, or alkyl esters of the acids are collectively referred to as carboxylic acid compounds.

--- Alcohol component--
There is no restriction | limiting in particular as said alcohol component, Although it can select suitably according to the objective from conventionally well-known things, For example, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) ) Aromatic alcohols of alkylene oxide adducts of bisphenol A such as propane and polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane; 1,2-propanediol, 1,3-propane Aliphatic dialcohols such as diol; ethylene glycol, propylene glycol, glycerin, pentaerythritol, trimethylolpropane, hydrogenated bisphenol A, sorbitol, or alkylene (2 to 4 carbon atoms) oxide (average number of added moles 1 to 16) ) Additives. These may be used individually by 1 type and may use 2 or more types together.
Among these, 1,2-propanediol is preferable from the viewpoint of imparting low-temperature fixability. The content of 1,2-propanediol is preferably 65 mol% or more, more preferably 80 mol% or more, and particularly preferably 90 mol% or more in the divalent alcohol component.

--Esterification catalyst--
The condensation polymerization of the alcohol component and the carboxylic acid component is preferably performed in the presence of an esterification catalyst. Examples of the esterification catalyst include a titanium compound and a tin (II) compound having no Sn—C bond, and these are used alone or in combination.

As said titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-C28 alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.
Examples of the titanium compound include titanium diisopropylate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₃ H ₇ O) ₂ ], titanium diisopropylate bisdiethanolamate [Ti (C _{4 H 10 O 2 N) 2 (} C 3 H 7 O) 2 ], titanium dipentylate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (C 5 H 11 O) 2 ], Chitanjiechi rate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (C 2 H 5 O) 2 ], titanium dihydroxy octylate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (OHC 8 H ₁₆ O) _2], titanium distearate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (C 18 H 37 O) 2 ], Chitanto Lysopropylate triethanolaminate [Ti (C ₆ H ₁₄ O ₃ N) ₁ (C ₃ H ₇ O) ₃ ], titanium monopropylate tris (triethanolaminate) [Ti (C ₆ H ₁₄ O ₃ N ) ₃ (C ₃ H ₇ O) ₁ ] and the like. Among these, titanium diisopropylate bistriethanolamate, titanium diisopropylate bisdiethanolamate, and titanium dipentylate bistriethanolamate are particularly preferable. These are also available as, for example, commercial products manufactured by Matsumoto Kosho Co., Ltd.

Specific examples of other preferable titanium compounds include tetra-n-butyl titanate [Ti (C ₄ H ₉ O) ₄ ], tetrapropyl titanate [Ti (C ₃ H ₇ O) ₄ ], tetrastearyl titanate [Ti ( C ₁₈ H ₃₇ O) _4], tetra myristyl titanate _{[Ti (C 14 H 29 O)} 4 ], tetraoctyl titanate _{[Ti (C 8 H 17 O)} 4 ], dioctyl-dihydroxy-octyl titanate [Ti _(C 8 _{H 17} O) ₂ (OHC ₈ H ₁₆ O) ₂ ], dimyristyl dioctyl titanate [Ti (C ₁₄ H ₂₉ O) ₂ (C ₈ H ₁₇ O) ₂ ] and the like. Among these, tetrastearyl titanate, tetramyristyl titanate, tetraoctyl titanate, and dioctyl dihydroxyoctyl titanate are preferable. These can be obtained, for example, by reacting a titanium halide with a corresponding alcohol, but can also be obtained as a commercial product such as Nisso Corporation.
0.01-1.0 mass part is preferable with respect to 100 mass parts of total amounts of the said alcohol component and the said carboxylic acid component, and, as for the abundance of the said titanium compound, 0.1-0.7 mass part is more preferable.

Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, and a tin (II) having a Sn—X bond (where X represents a halogen atom). A compound etc. are preferable and the tin (II) compound which has a Sn-O bond is more preferable.
Examples of the tin (II) compound having a Sn-O bond include tin (II) oxalate, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, and tin (II) distearate. Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms such as tin (II) dioleate; Dialkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms, such as tin oxide (II) and tin sulfate (II).
Examples of the compound having a Sn—X (wherein X represents a halogen atom) bond include tin (II) halides such as tin (II) chloride and tin (II) bromide. Among these, fatty acid tin (II) represented by (R ¹ COO) ₂ Sn (wherein R ¹ represents an alkyl group or alkenyl group having 5 to 19 carbon atoms) from the standpoint of charge rising effect and catalytic ability. , (R ² O) ₂ Sn (wherein R ² represents an alkyl group or alkenyl group having 6 to 20 carbon atoms), dialkoxy tin (II) represented by SnO, tin oxide (II) represented by SnO Preferred are fatty acid tin (II) and tin (II) oxide represented by (R ¹ COO) ₂ Sn, and particularly preferred are tin (II) dioctanoate, tin (II) distearate, and tin (II) oxide. .
The abundance of the tin (II) compound having no Sn—C bond is preferably 0.01 to 1.0 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 1 to 0.7 parts by mass.

When the titanium compound and the tin (II) compound having no Sn—C bond are used in combination, the total amount of the titanium compound and the tin (II) compound is 100% of the total amount of the alcohol component and the carboxylic acid component. 0.01-1.0 mass part is preferable with respect to mass part, and 0.1-0.7 mass part is more preferable.
The polycondensation of the alcohol component and the carboxylic acid component can be performed, for example, at a temperature of 180 to 250 ° C. in an inert gas atmosphere in the presence of the esterification catalyst.

As the polyester resin used in the present invention, an alcohol component containing 65 mol% or more of 1,2-propanediol in a divalent alcohol component and a carboxylic acid containing purified rosin are used to ensure low-temperature fixability. Those obtained by polycondensation with an acid component are preferred.
1,2-propanediol, which is a branched-chain alcohol having 3 carbon atoms, used as an alcohol component, improves low-temperature fixability while maintaining offset resistance as compared with alcohol having 2 or less carbon atoms. It is effective for preventing the deterioration of the storage stability accompanying the decrease of the glass transition temperature as compared with the branched alcohol having 4 or more carbon atoms. Therefore, when 1,2-propanediol is contained in an amount of 65 mol% or more in the divalent alcohol component, fixing at an extremely low temperature is possible, and storage stability is improved.

Moreover, as a polyester resin used by this invention, even if it contains the polyester resin (A) with a high softening point and the polyester resin (B) with a low softening point from a viewpoint of further improving low temperature fixability. Good.
The polyester resin (A) preferably has a softening point Tm (A) of 120 ° C. or higher and 160 ° C. or lower, more preferably 130 to 155 ° C., and particularly preferably 135 to 155 ° C. On the other hand, the polyester resin (B) has a softening point Tm (B) of preferably 80 ° C. or higher and lower than 120 ° C., more preferably 85 to 115 ° C., and particularly preferably 90 to 110 ° C. The difference (ΔTm) between Tm (A) and Tm (B) is preferably 10 ° C. or more, more preferably 15 to 55 ° C., and particularly preferably 20 to 50 ° C. The polyester resin (A) with a high softening point contributes to the improvement in offset resistance, and the polyester resin (B) with a low softening point contributes to an improvement in low-temperature fixability. It is effective for achieving both offset properties.
The mass ratio (polyester (A) / polyester (B)) in the binder resin between the polyester resin (A) and the polyester resin (B) is preferably 1/9 to 9/1, and 2/8 to 8/2. Is more preferable, and 3/7 to 7/3 is particularly preferable.

The glass transition temperature of the polyester resin used in the present invention is preferably 45 to 75 ° C, more preferably 50 to 65 ° C, from the viewpoints of fixability, storage stability, and durability.
The acid value of the polyester resin is preferably 1 to 80 mgKOH / g, more preferably 10 to 50 mgKOH / g, from the viewpoints of chargeability and environmental stability.
The polyester resin used in the present invention may be a modified polyester resin. The modified polyester resin refers to polyester grafted or blocked with phenol, urethane or the like.
By using the polyester resin as a binder resin for toner, it is possible to obtain a toner that is excellent in both low-temperature fixability and storage stability and also has reduced odor during fixing. The toner includes a known binder resin, for example, a vinyl resin such as a styrene-acrylic resin; other resins such as an epoxy resin, a polycarbonate resin, and a polyurethane resin, as long as the objects and effects of the present invention are not impaired. Although it may be used in combination, the content of the polyester resin in the binder resin is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and substantially 100% by mass. It is particularly preferred that

  The toner includes a colorant, a release agent, and, if necessary, a charge control agent, an external additive, a fluidity improver, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, and an antioxidant. In addition, additives such as an antiaging agent and a cleaning property improving agent may be appropriately contained.

-Graft polymer-
The graft polymer used in the present invention has a structure in which a polyolefin resin is grafted with at least a vinyl resin, and can be produced by a conventionally known method. That is, a polyolefin resin constituting the main chain of the graft polymer is dissolved in an organic solvent, a vinyl monomer for vinyl resin constituting a side chain is added to this solution, and the polyolefin resin and the vinyl monomer are combined with an organic solvent. A graft polymerization reaction is carried out in the presence of a polymerization initiator such as an organic peroxide.
The mass ratio of the polyolefin resin to the vinyl monomer is preferably 1 to 30:70 to 99, more preferably 2 to 27:83 to 98, from the viewpoint of preventing filming.
The graft polymer obtained by the graft polymerization contains an unreacted polyolefin resin and an ungrafted vinyl resin formed by polymerization of vinyl monomers. In the present invention, these polyolefin resin and vinyl resin are mixed. It is not necessary to separate and remove from the graft polymer, and the graft polymer can be preferably used as a mixed resin containing these components.
In the mixed resin, the content of the polyolefin resin is 5% by mass or less, and preferably 3% by mass or less. The content of the vinyl resin is 10% by mass or less, and preferably 5% by mass or less. Therefore, the ratio of the graft polymer in the mixed resin is 85% by mass or more, and preferably 90% by mass or more.
The ratio and molecular weight of the graft polymer resin in the mixed resin, the molecular weight of the vinyl polymer, and the like can be appropriately adjusted depending on conditions such as the charging ratio of the reaction raw materials, the polymerization reaction temperature, and the reaction time.

In the toner of the present invention, at least a part of the release agent is encapsulated in or attached to the graft polymer.
In the toner composition liquid in which the toner composition containing the release agent and the graft polymer is dissolved or dispersed and liquefied, the graft polymer suppresses the movement and reaggregation of the refined release agent. This is presumably because the polyolefin resin part of the graft polymer has a high affinity with the release agent and the vinyl resin part has a high affinity with the binder resin, thereby producing a dispersant effect.

Examples of the olefins constituting the polyolefin resin include ethylene, propylene, 1-butene, isobutylene, 1-hexene, 1-dodecene, and 1-octadecene.
Examples of the polyolefin-based resin include olefin polymers and thermal degradation products thereof, olefin polymer oxides, modified olefin polymers, and other monomers copolymerizable with olefins. Examples include copolymers.
Examples of the olefin polymers include polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, propylene / 1-hexene copolymer, and the like. Examples of the olefin polymer oxide include oxides of the olefin polymers exemplified above.
A heat-degraded product of an olefin polymer is a polyolefin resin obtained by heating a polyolefin resin having a mass average molecular weight of 50,000 to 5,000,000 to 250 ° C. to 450 ° C. and deriving from the number average molecular weight after heat degradation. The double bond content per molecule corresponding to the number of molecules to be removed is preferably 30 to 70%.
Examples of the modified product of the olefin polymer include a maleic acid derivative adduct of the olefin polymer exemplified above. Examples of the maleic acid derivative adduct include maleic anhydride, monomethyl maleate, monobutyl maleate, and dimethyl maleate.
Examples of copolymers with other monomers copolymerizable with the olefins include copolymers of monomers such as unsaturated carboxylic acids and unsaturated carboxylic acid alkyl esters with olefins, and the like. Can be mentioned. Examples of the unsaturated carboxylic acid include (meth) acrylic acid, itaconic acid, maleic anhydride, and the like. Examples of the unsaturated carboxylic acid alkyl ester include (meth) acrylic acid alkyl esters having 1 to 18 carbon atoms, maleic acid alkyl esters having 1 to 18 carbon atoms, and the like.

  The polyolefin resin used in the present invention may have a polymer structure having a polyolefin structure, and the monomer does not necessarily have an olefin structure. For this reason, for example, polymethylene such as sasol wax can also be used.

  Among these polyolefin resins, olefin polymers, heat-reduced polyolefins, olefin polymer oxides, and olefin polymer modified products are preferred, such as polyethylene, polymethylene, polypropylene, ethylene / propylene copolymer. A coalescence and heat-degraded product thereof, oxidized polyethylene, oxidized polypropylene, maleated polypropylene, etc. are more preferred, and heat-degraded products of polyethylene and polypropylene are particularly preferred.

The softening point of the polyolefin resin is usually from 60 to 170 ° C., and from the viewpoint of improving the fluidity of the toner and exhibiting an effective release effect, it is preferably from 70 to 150 ° C.
The molecular weight of the polyolefin resin is usually a number average molecular weight of 500 to 20,000, a mass average molecular weight of 800 to 100,000, and a number average molecular weight of 1 from the viewpoints of filming to a carrier and releasability. 1,000 to 15,000, preferably a mass average molecular weight of 1,500 to 60,000, a number average molecular weight of 1,500 to 10,000, and a mass average molecular weight of 2,000 to 30,000. Is particularly preferred.

As the vinyl resin, conventionally known homopolymers or copolymers of vinyl monomers can be used.
Specifically, styrene monomers, alkyl esters of unsaturated carboxylic acids having 1 to 18 carbon atoms, vinyl ester monomers, vinyl ether monomers, halogen element-containing vinyl monomers, diene monomers, (meth) acrylonitrile, cyano Examples thereof include unsaturated nitrile monomers such as styrene. These may be used individually by 1 type and may use 2 or more types together.
Examples of the styrene monomer include styrene, α-methyl styrene, p-methyl styrene, m-methyl styrene, p-methoxy styrene, p-hydroxy styrene, p-acetoxy styrene, vinyl toluene, ethyl styrene, phenyl styrene, Examples include benzylstyrene.
Examples of the alkyl ester of an unsaturated carboxylic acid having 1 to 18 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and the like.
Examples of the vinyl ester monomer include vinyl acetate, the vinyl ether monomer includes vinyl methyl ether, and the halogen element-containing vinyl monomer includes vinyl chloride. Examples of the diene monomer include butadiene and isobutylene.
Among these, a styrene monomer, an unsaturated carboxylic acid alkyl ester, (meth) acrylonitrile, and a combination thereof are preferable, and a combination of styrene; styrene and a (meth) acrylic acid alkyl ester or (meth) acrylonitrile is particularly preferable.

The SP value (solubility parameter) of the vinyl resin is preferably 10.0 to 11.5 (cal / cm ³ ) ^1/2 . The SP value of the vinyl resin is adjusted in consideration of the SP value of the binder resin. The SP value can be calculated by a known Fedors method.

The molecular weight of the vinyl resin is usually 1,500 to 100,000, the number average molecular weight is 5,000 to 200,000, the number average molecular weight is 2,500 to 5,0000, and the mass average. The molecular weight is preferably 6,000 to 100,000, the number average molecular weight is preferably 2,800 to 20,000, and the mass average molecular weight is particularly preferably 7,000 to 50,000.
The Tg (glass transition point) of the vinyl resin is usually 40 to 90 ° C., preferably 45 to 80 ° C., particularly 50 to 70 ° C. from the viewpoint of good storage stability and good low-temperature fixability. preferable.

Specific examples of the graft polymer of the present invention include those composed of the following polyolefin resin (A) and vinyl resin (B).
(A): oxidized polypropylene, (B): styrene / acrylonitrile copolymer (A): polyethylene / polypropylene mixture, (B): styrene / acrylonitrile copolymer (A): ethylene / propylene copolymer, (B ): Styrene / acrylic acid / butyl acrylate copolymer (A): polypropylene, (B): styrene / acrylonitrile / butyl acrylate / monobutyl maleate copolymer (A): maleic acid modified polypropylene, (B): Styrene / acrylonitrile / acrylic acid / butyl acrylate copolymer (A): maleic acid modified polypropylene, (B): styrene / acrylonitrile / acrylic acid / 2-ethylhexyl acrylate copolymer (A): polyethylene / maleic acid modified Polypropylene mixture, (B): acrylonitrile / Butyl acrylate / styrene / monobutyl maleate copolymer

As the method for producing the graft polymer, for example, first, wax such as polyolefin resin is dissolved or dispersed in a solvent such as toluene and xylene and heated to 100 to 200 ° C. A method of obtaining a graft polymer by evaporating the solvent after dropping polymerization together with the agent. Examples of the peroxide initiator include benzoyl peroxide, ditertiary butyl peroxide, and tertiary butyl peroxide benzoate.
The amount of the peroxide-based initiator can be appropriately adjusted based on the mass of the reaction raw material, and is usually 0.2 to 10% by mass, preferably 0.5 to 5% by mass.

The graft polymer may be mixed with an unreacted polyolefin resin and a vinyl resin formed by polymerization of vinyl monomers. In the case of the present invention, it is not necessary to separate and remove these polyolefin resin and vinyl resin from the graft polymer, and the graft polymer can be preferably used as a mixed resin containing these components.
The amount of each component constituting the graft polymer can be appropriately adjusted based on the weight of the generated graft polymer. Usually, the polyolefin resin is 1 to 90% by mass, and preferably 5 to 80% by mass. . Moreover, vinyl-type resin is 10-99 mass% normally, and 20-95 mass% is preferable.
Moreover, the addition amount of the graft polymer including unreacted polyolefin resin and vinyl resin is usually 5 to 300 parts by weight with respect to 100 parts by weight of the release agent from the viewpoint of dispersion stability of the release agent. Yes, 10 to 150 parts by mass are preferable.

-Colorant-
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, Cad Muum Mercury Red, Antimon Zhu, Permanent Red 4R, PA Red, Faise 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, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oh Lured, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, 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, Oxidation Chrome, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Ash Examples include degreen lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, and lithobon. These may be used individually by 1 type and may use 2 or more types together.

There is no restriction | limiting in particular as a color of the said coloring agent, According to the objective, it can select suitably, For example, the thing for black, the thing for color, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
Examples of the black material include carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, and channel black, copper, iron (CI pigment black 11), and titanium oxide. And organic pigments such as aniline black (CI Pigment Black 1).
Examples of the magenta color pigment include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48: 1, 49, 50, 51, 52, 53, 53: 1, 54, 55, 57, 57: 1, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 177, 179, 202, 206, 207, 209, 211; C.I. I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.
Examples of the color pigment for cyan include C.I. I. Pigment Blue 2, 3, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17, 60; I. Bat Blue 6; C.I. I. Acid Blue 45, copper phthalocyanine pigments having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton, green 7 and green 36, and the like.
Examples of the color pigment for yellow include C.I. I. Pigment Yellow 0-16, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 55, 65, 73, 74, 83, 97, 110, 151, 154, 180; C.I. I. Bat yellow 1, 3, 20, orange 36 and the like.

  The content of the colorant in the toner is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1 to 15% by mass, and more preferably 3 to 10% by mass. When the content is less than 1% by mass, a reduction in the coloring power of the toner is observed. When the content exceeds 15% by mass, poor dispersion of the pigment in the toner occurs, the coloring power decreases, and the electrical characteristics of the toner. May be reduced.

  The colorant may be used as a master batch combined with a resin. The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, styrene or a substituted polymer thereof, styrene copolymer, polymethyl methacrylate resin, polybutyl Methacrylate resin, polyvinyl chloride resin, polyvinyl acetate resin, polyethylene resin, polypropylene resin, polyester resin, epoxy resin, epoxy polyol resin, polyurethane resin, polyamide resin, polyvinyl butyral resin, polyacrylic acid resin, rosin, modified rosin, terpene Examples thereof include resins, aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, and paraffins. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the styrene or substituted polymer thereof include polyester resin, polystyrene resin, poly p-chlorostyrene resin, and polyvinyl toluene resin. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene An acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - like maleic acid ester copolymer.

  The masterbatch can be produced by mixing or kneading the masterbatch resin and the colorant under high shear. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. Also, the so-called flushing method is preferable in that the wet cake of the colorant can be used as it is, and there is no need to dry it. The flushing method is a method of mixing or kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, and transferring the colorant to the resin side to remove moisture and the organic solvent component. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill is preferably used.

-Release agent-
There is no restriction | limiting in particular as said mold release agent, According to the objective, it can select suitably from well-known things, For example, waxes, such as carbonyl group containing wax, polyolefin wax, and long-chain hydrocarbon, are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, a carbonyl group-containing wax is preferable.

Examples of the carbonyl group-containing wax include polyalkanoic acid esters, polyalkanol esters, polyalkanoic acid amides, polyalkylamides, dialkyl ketones, and the like. Examples of the polyalkanoic acid ester include carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, and 1,18-octadecane. Examples thereof include diol distearate. Examples of the polyalkanol ester include tristearyl trimellitic acid and distearyl maleate. Examples of the polyalkanoic acid amide include dibehenyl amide. Examples of the polyalkylamide include trimellitic acid tristearylamide. Examples of the dialkyl ketone include distearyl ketone. Among these carbonyl group-containing waxes, polyalkanoic acid esters are particularly preferable.
Examples of the polyolefin wax include polyethylene wax and polypropylene wax.
Examples of the long chain hydrocarbon include paraffin wax and sazol wax.

There is no restriction | limiting in particular as melting | fusing point of the said mold release agent, Although it can select suitably according to the objective, 40-160 degreeC is preferable, 50-120 degreeC is more preferable, 60-90 degreeC is especially preferable. If the melting point is less than 40 ° C., the heat resistant storage stability may be adversely affected. If the melting point exceeds 160 ° C., cold offset may easily occur during fixing at a low temperature.
The melting point of the release agent is, for example, a sample which is heated to 200 ° C. using a differential scanning calorimeter (Seiko Electronics Co., Ltd., DSC210) and cooled to 0 ° C. at a temperature decreasing rate of 10 ° C./min. And the maximum peak temperature of heat of fusion can be determined as the melting point.
The melt viscosity of the release agent is preferably 5 to 1,000 cps, more preferably 10 to 100 cps, as a measured value at a temperature 20 ° C. higher than the melting point of the wax. If the melt viscosity is less than 5 cps, the releasability may be lowered, and if it exceeds 1,000 cps, the effect of improving hot offset resistance and low-temperature fixability may not be obtained.

There is no restriction | limiting in particular as content in the said toner of the said mold release agent, Although it can select suitably according to the objective, 0-40 mass% is preferable and 3-30 mass% is more preferable.
When the content exceeds 40% by mass, the fluidity of the toner may be deteriorated.

-Charge control agent-
The charge control agent is not particularly limited and may be appropriately selected from known ones according to the purpose. However, since a color tone may change when a colored material is used, a colorless or nearly white material may be used. Preferably, for example, triphenylmethane dyes, molybdate chelate pigments, rhodamine dyes, alkoxyamines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus alone or compounds thereof, tungsten Examples thereof include a single substance or a compound thereof, a fluorine-based activator, a metal salt of salicylic acid, and a metal salt of a salicylic acid derivative. These may be used individually by 1 type and may use 2 or more types together.

Commercially available products may be used as the charge control agent. Examples of the commercially available products include quaternary ammonium salt Bontron P-51, oxynaphthoic acid metal complex E-82, and salicylic acid metal complex. E-84, phenolic condensate E-89 (all manufactured by Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302, TP-415 (all manufactured by Hodogaya Chemical Co., Ltd.), No. Quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (both manufactured by Hoechst); LRA-901, boron complex LR-147 (Nippon Carlit Co., Ltd.); quinacridone, azo pigment; sulfone Group, a carboxyl group, and the like and polymeric compounds having a functional group such as a quaternary ammonium salt.
The charge control agent may be melted and kneaded with the master batch and then dissolved or dispersed, or may be added together with the toner components when directly dissolving or dispersing in the organic solvent, or the toner. You may fix to the toner surface after particle manufacture.

  The content of the charge control agent in the toner varies depending on the type of the binder resin, the presence / absence of an additive, a dispersion method, and the like, and cannot be generally specified. On the other hand, 0.1-10 mass parts is preferable, and 0.2-5 mass parts is more preferable. When the content is less than 0.1 parts by mass, the charge controllability may not be obtained. When the content exceeds 10 parts by mass, the chargeability of the toner becomes too large, and the effect of the main charge control agent is reduced. As a result, the electrostatic attractive force with the developing roller increases, which may lead to a decrease in developer fluidity and a decrease in image density.

-External additive-
The external additive is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, silica fine particles, hydrophobized silica fine particles, fatty acid metal salts (for example, zinc stearate, And aluminum oxide stearate); metal oxides (for example, titania, alumina, tin oxide, antimony oxide, etc.) or their hydrophobized products, fluoropolymers, and the like. Among these, hydrophobized silica fine particles, titania particles, and hydrophobized titania fine particles are preferable.

  Examples of the silica fine particles include HDK H 2000, HDK H 2000/4, HDK H 2050EP, HVK21, HDK H1303 (all manufactured by Hoechst); R972, R974, RX200, RY200, R202, R805, R812 (all Japan) Aerosil Co., Ltd.). Examples of the titania fine particles include P-25 (manufactured by Nippon Aerosil Co., Ltd.), STT-30, STT-65C-S (all 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.) and the like. Examples of the hydrophobized titanium oxide 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 ( All are Fuji Titanium Industry Co., Ltd.); MT-100S, MT-100T (both are Teika Co., Ltd.), IT-S (Ishihara Sangyo Co., Ltd.) and the like.

In order to obtain the hydrophobized silica fine particles, hydrophobized titania fine particles, and hydrophobized alumina fine particles, the hydrophilic fine particles are made of silane cups such as methyltrimethoxysilane, methyltriethoxysilane, and octyltrimethoxysilane. It can be obtained by treating with a ring agent.
Examples of the hydrophobizing agent include silane coupling agents such as dialkyl dihalogenated silanes, trialkyl halogenated silanes, alkyl trihalogenated silanes, and hexaalkyldisilazanes, silylating agents, and silane couplings having a fluorinated alkyl group. Agents, organic titanate coupling agents, aluminum coupling agents, silicone oils, silicone varnishes and the like.

In addition, silicone oil-treated inorganic fine particles obtained by treating the inorganic fine particles with silicone oil if necessary are also suitable.
Examples of the inorganic fine particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, silica sand, clay, mica, silica Examples include apatite, 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-modified. Examples include 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, and α-methylstyrene-modified silicone oil.

The average particle size of the primary particles of the inorganic fine particles is preferably 1 to 100 nm, and more preferably 3 to 70 nm. When the average particle size is less than 1 nm, the inorganic fine particles are buried in the toner and the function thereof may not be effectively exhibited. When the average particle size exceeds 100 nm, the surface of the electrostatic latent image carrier is damaged nonuniformly. It may end up. As the external additive, inorganic fine particles or hydrophobic treated inorganic fine particles can be used in combination, but the average particle size of the hydrophobized primary particles is preferably 1 to 100 nm, more preferably 5 to 70 nm. More preferably, the primary particles subjected to the hydrophobization treatment include at least two types of inorganic fine particles having an average particle size of 20 nm or less and at least one type of inorganic fine particles of 30 nm or more. Moreover, it is preferable that the specific surface area by BET method of the said inorganic fine particle is 20-500 m < ² > / g.
The amount of the external additive added is preferably 0.1 to 5% by mass and more preferably 0.3 to 3% by mass with respect to the toner.

  Resin fine particles can also be added as the external additive. For example, polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, or dispersion polymerization; copolymer of methacrylic acid ester, acrylic acid ester; polycondensation system such as silicone, benzoguanamine, nylon; polymer particles made of thermosetting resin It is done. By using such resin fine particles in combination, the chargeability of the toner can be enhanced, the reversely charged toner can be reduced, and the background stain can be reduced. The addition amount of the resin fine particles is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass with respect to the toner.

The fluidity improver can be surface-treated to increase hydrophobicity and prevent deterioration of fluidity and charging characteristics even under high humidity. For example, a silane coupling agent, a silylating agent, and a fluoride can be used. Examples thereof include silane coupling agents having an alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils. The particle size of the fluidity improver is preferably 0.001 to 2 μm, more preferably 0.002 to 0.2 μm, as an average primary particle size.
The cleaning improver is added to the toner to remove the developer after transfer remaining on the electrostatic latent image carrier or the intermediate transfer member. For example, fatty acid such as zinc stearate, calcium stearate, stearic acid Metal salts; 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 those having a volume average particle size of 0.01 to 1 μm are suitable.
There is no restriction | limiting in particular as said magnetic material, According to the objective, it can select suitably from well-known things, For example, iron powder, a magnetite, a ferrite, etc. are mentioned. Among these, white is preferable in terms of color tone.

-Toner production method-
The method for producing the toner is not particularly limited and may be appropriately selected from conventionally known toner production methods depending on the purpose. Examples thereof include a spray granulation method.

--Kneading and grinding method--
The kneading and pulverizing method is, for example, a method of producing the toner base particles by melt-kneading a toner material containing at least a binder resin and a colorant, pulverizing and classifying the obtained kneaded material. is there.
In the melt kneading, the toner materials are mixed, and the mixture is charged into a melt kneader and melt kneaded. As the melt kneader, for example, a uniaxial or biaxial continuous kneader or a batch kneader using a roll mill can be used. For example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type extruder manufactured by Toshiba Machine Co., Ltd., twin screw extruder manufactured by Casey Kay Co., Ltd. Used. This melt-kneading is preferably performed under appropriate conditions so as not to cause the molecular chains of the binder resin to be broken. Specifically, the melt-kneading temperature is determined with reference to the softening point of the binder resin. If the temperature is too high, the cutting may be severe, and if the temperature is too low, the dispersion may not proceed.

  In the pulverization, the kneaded product obtained by the kneading is pulverized. In this pulverization, it is preferable that the kneaded material is first coarsely pulverized and then finely pulverized. At this time, a method of pulverizing by colliding with a collision plate in a jet stream, pulverizing particles by colliding with each other in a jet stream, or pulverizing with a narrow gap between a mechanically rotating rotor and a stator is preferably used.

In the classification, the pulverized product obtained by the pulverization is classified and adjusted to particles having a predetermined particle diameter. The classification can be performed, for example, by removing the fine particle portion with a cyclone, a decanter, a centrifuge, or the like.
After the pulverization and classification are completed, the pulverized product is classified into an air stream by centrifugal force or the like, and a toner base having a predetermined particle diameter can be manufactured.

  Next, external additives are externally added to the toner base. By mixing and stirring the toner base and the external additive using a mixer, the surface of the toner base is coated while being crushed. At this time, it is important in terms of durability that the external additives such as inorganic fine particles and resin fine particles are uniformly and firmly attached to the toner base.

--- Polymerization method--
As a method for producing a toner by the polymerization method, for example, a toner material containing at least a modified polyester resin capable of urea or urethane bonding and a colorant is dissolved or dispersed in an organic solvent. Then, this dissolved or dispersed material is dispersed in an aqueous medium, subjected to a polyaddition reaction, and the solvent of this dispersion is removed and washed.

  Examples of the modified polyester-based resin capable of bonding with urea or urethane include, for example, a polyester prepolymer having an isocyanate group obtained by reacting a carboxyl group or a hydroxyl group at a terminal of a polyester with a polyvalent isocyanate compound (PIC). Can be mentioned. The modified polyester resin obtained by crosslinking and / or extending the molecular chain by the reaction of this polyester prepolymer and amines can improve the hot offset property while maintaining the low temperature fixability.

Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane). Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; And those blocked with oxime, caprolactam, and the like. These may be used individually by 1 type and may use 2 or more types together.
The ratio of the polyvalent isocyanate compound (PIC) is preferably 5/1 to 1/1 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 is more preferable, and 2.5 / 1 to 1.5 / 1 is particularly preferable.

  The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having the isocyanate group is preferably 1 or more, more preferably 1.5 to 3 on average, and 1.8 to 2.5 on average. Is particularly preferred.

Examples of amines (B) to be reacted with the polyester prepolymer include a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4), an amino acid (B5). ), B1 to B5 amino groups blocked (B6), and the like.
Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-). Dimethyl dicyclohexyl methane, diamine cyclohexane, isophorone diamine, etc.); 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 the amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of the amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazolidine compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). . Among these amines (B), B1 and a mixture of B1 and a small amount of B2 are particularly preferable.

  The ratio of the amines (B) is equivalent to the equivalent ratio [NCO] / [NHx of the isocyanate group [NCO] in the polyester prepolymer (A) having an isocyanate group and the amino group [NHx] in the amine (B). ] Is preferably 1/2 to 2/1, more preferably 1.5 / 1 to 1 / 1.5, and particularly preferably 1.2 / 1 to 1 / 1.2.

  According to the method for producing a toner by the polymerization method as described above, a toner having a small particle diameter and a spherical shape can be produced at low cost with little environmental load.

  The volume average particle diameter of the toner is preferably 4 to 12 μm, and more preferably 4 to 10 μm. When the volume average particle size is less than 4 μm, it is advantageous for obtaining a high-resolution and high-quality image, but tends to be disadvantageous for transferability and cleaning properties. Also, the smaller the toner particle size, the easier it is for the toner to fuse to the carrier surface, and the chargeability of the carrier may be reduced faster. On the other hand, when the volume average particle diameter exceeds 12 μm, it may be difficult to obtain a high-resolution image. The same applies to the ratio of the volume average particle diameter to the number average particle diameter of the toner (volume average particle diameter / number average particle diameter). That is, if the number average particle diameter is too large with respect to the volume average particle diameter, the toner may be easily fused to the carrier surface because there are many fine powders. Accordingly, the ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) of the toner is preferably 1.20 or less.

<Magnetic carrier>
There is no restriction | limiting in particular as said magnetic carrier, Although it can select suitably according to the objective, Normal magnetic carriers, such as a ferrite and a magnetite; Resin coat carrier can also be used. Among these, a resin coat carrier is particularly preferable.

The resin-coated carrier includes a core material and a coating layer containing a resin that coats (coats) the surface of the core material.
There is no restriction | limiting in particular as resin used for the said coating layer, Although it can select suitably according to the objective, For example, styrene-acrylic systems, such as a styrene-acrylic acid ester copolymer and a styrene-methacrylic acid ester copolymer, Resin; Acrylic resin such as acrylic ester copolymer and methacrylic ester copolymer; Fluorine-containing resin such as polytetrafluoroethylene, monochlorotrifluoroethylene polymer and polyvinylidene fluoride; Silicone resin, polyester resin, polyamide resin , Polyvinyl butyral, and aminoacrylate resin are preferable. Besides these, ionomer resins, polyphenylene sulfide resins, and the like can be given. Of these coating resins, styrene-methyl methacrylate copolymers, mixtures of fluorine-containing resins and styrene copolymers, and silicone resins are preferred, and silicone resins are particularly preferred.

The silicone resin is not particularly limited and can be appropriately selected according to the purpose from generally known silicone resins. For example, a straight silicone resin consisting only of an organosilosan bond; an alkyd resin; Examples thereof include polyester resins, epoxy resins, acrylic resins, silicone resins modified with urethane resins, and the like.
Commercially available products can be used as the silicone resin. Examples of straight silicone resins include KR271, KR255, and KR152 manufactured by Shin-Etsu Chemical Co., Ltd .; SR2400, SR2406, and SR2410 manufactured by Toray Dow Corning Silicone Co., Ltd. Etc.
Commercially available products can be used as the modified silicone resin, such as KR206 (alkyd modified), KR5208 (acrylic modified), ES1001N (epoxy modified), KR305 (urethane modified) manufactured by Shin-Etsu Chemical Co., Ltd .; SR2115 (epoxy-modified), SR2110 (alkyd-modified) manufactured by Dow Corning Silicone Co., Ltd. and the like can be mentioned.

For example, the coating 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 application method include an immersion method, a spray method, and a brush coating method.
There is no restriction | limiting in particular as said solvent, Although it can select suitably according to the objective, For example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cellosolve, butyl acetate, etc. are mentioned.
The baking is not particularly limited, and may be an external heating method or an internal heating method. For example, a stationary electric furnace, a fluid electric furnace, a rotary electric furnace, a burner furnace, The method of using, the method of using a microwave, etc. are mentioned.

  The amount of the resin layer in the carrier is preferably 0.01 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.

Examples of the core material that can be used include oxides such as ferrite, iron-rich ferrite, magnetite, and γ-iron oxide, metals such as iron, cobalt, and nickel, or alloys thereof.
Examples of elements contained in these magnetic materials include iron, cobalt, nickel, aluminum, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, calcium, manganese, selenium, titanium, tungsten, and vanadium. It is done. Of these, copper-zinc-iron-based ferrites mainly composed of copper, zinc, and iron components, and manganese-magnesium-iron-based ferrites mainly composed of manganese, magnesium, and iron components are preferable.

The particle diameter of the core material is preferably an average particle diameter (volume average particle diameter (D ₅₀ )) of 10 to 200 μm, and more preferably 40 to 100 μm. If the average particle size (volume average particle size (D ₅₀ )) is less than 10 μm, the carrier particle distribution may increase the number of fine powders, lowering the magnetization per particle and causing carrier scattering. If the thickness exceeds 200 μm, the specific surface area may be reduced and toner scattering may occur. In the case of a full color having many solid portions, the reproduction of the solid portions may be particularly poor.

The resistance value of the carrier is preferably 10 ⁶ to 10 ¹⁰ Ω · cm by adjusting the unevenness of the surface of the carrier and the amount of resin to be coated.
The particle size of the carrier is preferably 4 to 200 μm, more preferably 10 to 150 μm, and particularly preferably 20 to 100 μm. In particular, the resin-coated carrier preferably has a 50% particle size of 20 to 70 μm.
In the two-component developer, it is preferably used in an amount of 1 to 200 parts by mass of toner with respect to 100 parts by mass of the carrier, and more preferably in an amount of 2 to 50 parts by mass of toner with respect to 100 parts by mass of the carrier. .

(Image forming method and image forming apparatus)
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, preferably including a cleaning step, and further other steps appropriately selected as necessary. For example, it includes a static elimination process, a recycling process, a control process, and the like.
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 preferably includes a cleaning unit. In addition, other means appropriately selected as necessary, for example, static elimination means, recycling means, control means, and the like are provided.

  The image forming method of the present invention can be preferably carried out by the image forming apparatus of the present invention, the electrostatic latent image forming step can be performed by the electrostatic latent image forming means, and the developing step is the developing The transfer step can be performed by the transfer unit, the fixing step can be performed by the fixing unit, the cleaning step can be performed by the cleaning unit, and the other steps. Can be performed by the other means.

<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 electrostatic latent image carrier (sometimes referred to as “photoreceptor”, “electrophotographic photoreceptor”, “image carrier”) is not particularly limited in terms of material, shape, structure, size, and the like. However, the shape may be appropriately selected according to the purpose, and examples of the shape include a drum shape, a sheet shape, and an endless belt shape. The structure may be a single-layer structure or a laminated structure, and the size may be appropriately selected according to the size and specifications of the image forming apparatus. Examples of the material include inorganic photoreceptors such as amorphous silicon, selenium, CdS, and ZnO; organic photoreceptors (OPC) such as polysilane and phthalopolymethine, and the like.

  For example, the amorphous silicon photosensitive member is heated to 50 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, or the like is applied on the support. A photosensitive layer made of a-Si is formed by a film forming method. Among these, the plasma CVD method is particularly preferable, and specifically, a method in which the source gas is decomposed by direct current, high frequency, or microwave glow discharge to form a photosensitive layer made of a-Si on the support is preferable. .

The organic photoreceptor (OPC) has (1) optical characteristics such as a wide light absorption wavelength range and a large amount of light absorption, (2) electrical characteristics such as high sensitivity and stable charging characteristics, (3) In general, it is widely applied because of the wide selection range of materials, (4) ease of production, (5) low cost, and (6) non-toxicity. The layer structure of such an organic photoreceptor is roughly divided into a single layer structure and a laminated structure.
The single-layered photoreceptor has a support and a single-layer type photosensitive layer provided on the support, and further includes a protective layer, an intermediate layer, and other layers as necessary.
The laminated structure of the photoreceptor comprises a support, and a laminate type photosensitive layer having at least a charge generation layer and a charge transport layer in this order on the support, and further includes a protective layer and an intermediate layer as necessary. And other layers.

  The formation of the electrostatic latent image can be performed, for example, by uniformly charging the surface of the electrostatic latent image carrier and then performing imagewise exposure, and is performed by the electrostatic latent image forming unit. be able to. The electrostatic latent image forming means includes, for example, at least a charging device that uniformly charges the surface of the electrostatic latent image carrier and an exposure device that exposes the surface of the electrostatic latent image carrier imagewise. Prepare.

The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charging device.
The charging device is not particularly limited and may be appropriately selected depending on the purpose. For example, the charging device known per se provided with a conductive or semiconductive roll, brush, film, rubber blade, etc. Non-contact charging device using corona discharge such as a device, corotron, scorotron, etc.

The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure unit.
The optical system in the exposure is roughly classified into an analog optical system and a digital optical system. The analog optical system is an optical system that projects an original directly onto an electrostatic latent image carrier by an optical system, and the digital optical system receives image information as an electrical signal and converts it into an optical signal. It is an optical system that exposes an electrostatic latent image carrier to form an image.
The exposure apparatus is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charging apparatus as an image to be formed, and is appropriately selected according to the purpose. For example, various exposure apparatuses such as a copying optical system, a rod lens array system, a laser optical system, a liquid crystal shutter optical system, and an LED optical system can be used.
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 two-component developer composed of a magnetic carrier and toner to form a visible image.
The visible image can be formed, for example, by developing the electrostatic latent image using the two-component developer, and can be performed by the developing unit.
The developing means is not particularly limited as long as it can be developed using a two-component developer composed of a magnetic carrier and a toner, and can be appropriately selected from known ones. For example, the two-component developer And at least a developing device that can apply the electrostatic latent image two-component developer in a contact or non-contact manner.

<Transfer process and transfer means>
The transfer step is a step of transferring the visible image onto a recording medium. After the primary transfer of the visible image onto the intermediate transfer member using an intermediate transfer member, the visible image is transferred onto the recording medium. A primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer body using two or more colors, preferably full color toner as the toner, and a composite transfer image; A mode including a secondary transfer step of transferring the transfer image onto the recording medium is more preferable.
The transfer can be performed, for example, by charging the latent electrostatic image bearing member (photoconductor) of the visible image 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.
The intermediate transfer member is not particularly limited and may be appropriately selected from known transfer members according to the purpose. For example, a transfer belt, a transfer roller, and the like are preferable.

The transfer means (the primary transfer means and the secondary transfer means) is a transfer for peeling and charging the visible image formed on the electrostatic latent image carrier (photoconductor) to the recording medium side. It is preferable to have at least a vessel. 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.
The recording medium is not particularly limited and can be appropriately selected from known recording media.

<Fixing process and fixing means>
The fixing step is a step of fixing the visible image transferred to the recording medium using the fixing unit, and may be performed each time the toner of each color is transferred to the recording medium, or may be applied to the toner of each color. On the other hand, it may be carried out simultaneously at the same time in a state of being laminated.
The fixing unit is not particularly limited and may be appropriately selected depending on the intended purpose, but a known heating and pressing unit is preferable. Examples of the heating and pressing means include a combination of a heating roller and a pressure roller, a combination of a heating roller, a pressure roller, and an endless belt.
The heating in the heating and pressing means is usually preferably 80 ° C to 200 ° C.
In the present invention, for example, a known optical fixing device may be used together with or in place of the fixing step and the fixing unit depending on the purpose.

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.

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.
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. Preferred examples include brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.

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.

The control means is a process for controlling the respective steps, and can be suitably performed by the control means.
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 a sequencer and a computer.

  Here, an embodiment applied to an electrophotographic copying machine (hereinafter also referred to as “copying machine”) which is an image forming apparatus of the present invention will be described. FIG. 1 is a schematic configuration diagram of the entire copying machine according to the present embodiment. FIG. 2 is a schematic configuration diagram showing the developing device of the copying machine of FIG.

The photosensitive drum 1 as an electrostatic latent image carrier has a photosensitive layer formed on the peripheral surface of the body, and is rotated in the direction of the arrow in the drawing by a driving mechanism (not shown). The rotating photosensitive drum 1 is first uniformly charged to a desired potential by the charging device 2 and then exposed by the exposure device 3 to form an electrostatic latent image corresponding to the image. The electrostatic latent image formed on the photosensitive drum 1 is visualized using the developing device 4.
In the developing device 4, a two-component developer 40 made of toner and magnetic carrier used for development is accommodated. Further, a developing sleeve 43 as a developer carrying member is installed so as to be partially exposed from a portion facing the photosensitive drum 1. A voltage is applied to the developing sleeve 43 by a power source 46 (see FIG. 2), and an electric field corresponding to the image is formed between the developing sleeve 43 and the electrostatic latent image on the photosensitive drum 1. The charged toner in the developer 40 drawn up on the developing sleeve 43 by this electric field adheres to the photosensitive drum 1 and forms a visible image (toner image). In FIG. 2, reference numeral 47 denotes a developer leveling member.

The visible image developed as described above is transferred from the photosensitive drum 1 to the recording medium S by the transfer device 5 and fixed on the paper by heat and pressure while the recording medium S passes through the fixing device 6. . On the other hand, the toner remaining on the photosensitive drum 1 without being transferred to the recording medium S is removed by the cleaning member 7. The cleaned toner passes through a recycled toner conveyance path (not shown) and is resupplied into the developing device 4 to be used for the next image formation.
As development is performed, the toner concentration in the developer decreases, but a necessary amount is replenished as needed by a toner replenishment mechanism (not shown), and image formation is repeatedly performed under the above-described steps.

The photosensitive drum 1 as an electrostatic latent image carrier is a photosensitive layer formed by applying a photosensitive inorganic or organic photosensitive material on an element tube such as aluminum, and the photosensitive layer generates charges. It consists of a layer and a charge transport layer, and the surface is uniformly charged by a charging device. A belt-shaped photoconductor may be used as the electrostatic latent image carrier.
In FIG. 2, the developing device 4 includes a developer storage chamber 41 that stores a two-component developer 40 composed of toner and a carrier, and a pair of members that are rotationally driven to stir and transport the two-component developer 40 therein. The screw 42 is provided. Further, a developing sleeve 43 as a developer carrying member is installed so as to be partially exposed from a portion facing the photosensitive drum 1. A partition is provided in the developer conveyance path (not shown) so that toner is replenished from a toner replenishing port (not shown) in the conveyance path far from the developing sleeve 43. The replenished toner is sufficiently mixed with the carrier while being conveyed in the longitudinal direction so that the two-component developer 40 is not supplied to the developing sleeve 43 in an unmixed state immediately after replenishment. Thereafter, the toner is transferred from the opening (not shown) to the other conveyance path, and is drawn up to the developing sleeve 43.

The developing sleeve 43 is made of a material such as aluminum or non-magnetic stainless steel, and is a non-magnetic cylindrical member having appropriate irregularities on the surface by forming a sandblast or a groove. The developing sleeve 43 is rotationally driven with a suitable linear speed by a rotational driving device (not shown). In addition, a two-component developer 40 is held by fixing and arranging a magnet roller 44 as a magnet member having a plurality of magnetic poles therein, and the two-component developer 40 is applied to the electrostatic latent image on the photosensitive drum 1. It can be transported and supplied.
The magnet roller 44 inside the developing sleeve 43 has a plurality of magnetic poles, each having a necessary role. Basically required are a development pole for raising the two-component developer 40 in the development area, a pumping pole for pumping the two-component developer 40 onto the development sleeve 43, and a conveyance pole for conveying the developer. It is possible to configure with 5 to 10 poles.

  Furthermore, a doctor blade 45 as a layer thickness regulating member is installed upstream of the closest contact between the developing sleeve 43 and the photosensitive drum 1 in the rotation direction of the developing sleeve 43. The doctor blade 45 regulates the developer amount on the developing sleeve 43 to a desired amount. Then, a magnetic brush is formed by the magnet roller 44 inside the developing sleeve 43 and brought into contact with the electrostatic latent image on the photosensitive drum 1. The developing sleeve 43 is connected to a power source 46 for applying a developing bias voltage for forming a developing electric field in a developing region between the developing drum 43 and the photosensitive drum 1. By this developing electric field, the charged toner in the developer on the developing sleeve 43 adheres to the electrostatic latent image on the photosensitive drum 1, whereby a visible image can be formed. The most mechanical hazard to the two-component developer 40 in the developing device is a step of regulating the developer layer thickness by the doctor blade 45, and the layer thickness regulating member and the developer carrying member The smaller the distance (doctor gap; DG), the greater the mechanical hazard. This distance (DG) is set in the range of 0.3 to 1.0 mm.

The linear velocity of the developing sleeve 43 is preferably used between 1.1 times and 3.0 times the linear velocity of the photosensitive drum 1, and more preferably between 1.5 times and 2.5 times. preferable. When used at a linear speed slower than this range, the image density is insufficient. On the other hand, if it is faster than this range, toner scattering and image disturbance may occur.
Further, the development gap (PG) between the photosensitive drum 1 and the development sleeve 43 has an optimum value depending on the carrier particle size and the pumping amount to be used. The range is set to 1.0 mm.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
In the following examples and comparative examples, “softening point of polyester resin”, “softening point of rosin”, “glass transition temperature (Tg) of polyester resin”, “SP value of rosin and vinyl resin”, “polyester resin and The acid value of rosin, the degree of modification of the modified rosin, and the number average molecular weight and mass average molecular weight of the graft polymer were measured as follows.

<Measurement of softening point of polyester resin>
Using a flow tester (manufactured by Shimadzu Corporation, CFT-500D), a 1 g sample was heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa was applied by a plunger, from a nozzle having a diameter of 1 mm and a length of 1 mm. Extrusion, the amount of plunger drop of the flow tester against temperature was plotted, and the temperature at which half of the sample flowed out was taken as the softening point.

<Measurement of softening point of rosin>
(1) Preparation of sample 10 g of rosin was melted on a hot plate at 170 ° C. for 2 hours. Then, it was naturally cooled for 1 hour in an environment of a temperature of 25 ° C. and a relative humidity of 50% in an opened state, and ground for 10 seconds with a coffee mill (National MK-61M) to prepare a sample.
(2) Measurement Using a flow tester (manufactured by Shimadzu Corporation, CFT-500D), a 1 g sample was heated at a heating rate of 6 ° C./min, a 1.96 MPa load was applied by a plunger, a diameter of 1 mm, a length The sample was extruded from a 1 mm nozzle, and the plunger drop amount of the flow tester was plotted against the temperature. The temperature at which half of the sample flowed out was taken as the softening point.

<Measurement of glass transition temperature (Tg) of polyester resin>
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), 0.01 to 0.02 g of sample was weighed into an aluminum pan, heated to 200 ° C., and the temperature was lowered at a rate of 10 ° C./min. The sample cooled to 0 ° C is heated at a heating rate of 10 ° C / min, and the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent line indicating the maximum slope from the peak rising portion to the peak apex Was defined as the glass transition temperature.

<SP value of rosin and vinyl resin>
Based on the Fedors method, it calculated by calculating | requiring the sum and the molar volume of the contribution to the cohesive energy density of the nuclear group which comprises.

<Acid value of polyester resin and rosin>
It measured based on the method of JISK0070. However, only the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K0070 to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

<Degree of modification of modified rosin>
[Softening point of rosin (Ts value)]
After pouring 2.1 g of the molten sample into a predetermined ring, the sample was cooled to room temperature and then measured under the following conditions based on JIS B7410.
Measuring machine: Ring-and-ball automatic softening point tester ASP-MGK2 (manufactured by Meitec)
Temperature increase rate: 5 ° C / min
Temperature rising start temperature: 40 ° C
Measuring solvent: Glycerin

(Degree of (meth) acrylic acid modification of rosin)
It calculated with the following formula (A).
Degree of (meth) acrylic acid modification = (X ₁ -Y) / (X ₂ -Y) × 100 Formula (A)
However, in formula (A), X ₁ represents the Ts value of (meth) acrylic acid-modified rosin for calculating the degree of modification, and X ₂ is obtained by reacting 1 mol of (meth) acrylic acid with 1 mol of rosin. The saturated Ts value of (meth) acrylic acid-modified rosin is represented, and Y represents the Ts value of rosin.
Here, the saturated Ts value means a Ts value when the reaction between (meth) acrylic acid and rosin is caused to react until the Ts value of the obtained (meth) acrylic acid-modified rosin reaches a saturation value.

[Fumaric acid modification degree of rosin]
It calculated by the following formula (Af).
Degree of fumaric acid modification = (Xf ₁ −Y) / (Xf ₂ −Y) × 100 Formula (Af)
In the formula (Af), Xf ₁ represents the Ts value of fumaric acid-modified rosin for calculating the degree of modification, and Xf ₂ represents fumaric acid-modified rosin obtained by reacting 1 mol of fumaric acid with 0.7 mol of rosin. Y represents the Ts value of rosin.
Here, the Ts value represented by Xf ₂ is as follows: a mixture of 1 mol of fumaric acid, 0.7 mol of rosin and 0.4 g of t-butylcatechol was heated from 160 ° C. to 200 ° C. over 2 hours, It is a Ts value of fumaric acid-modified rosin obtained by reacting at 2 ° C. for 2 hours and further performing distillation under reduced pressure of 5.3 kPa.

[Degree of maleic acid modification of rosin]
It calculated by the following formula (Am).
Maleic acid modification degree = (Xm ₁ −Y) / (Xm ₂ −Y) × 100 Formula (Af)
In the formula (Am), Xm ₁ represents the Ts value of maleic acid-modified rosin for calculating the degree of modification, and Xm ₂ represents maleic acid obtained by reacting 1 mol of maleic acid and 1 mol of rosin at 230 ° C. The saturated Ts value of the modified rosin is represented, and Y represents the Ts value of the rosin.
Here, the saturated Ts value means the Ts value when the reaction of maleic acid and rosin is caused to react until the Ts value of the resulting maleic acid-modified rosin reaches the saturation value.

In the formulas (A), (Af), and (Am), the molecular weight of 1 mol of rosin is potassium hydroxide (molecular weight: 56) with respect to 1 g of rosin when the acid value is x (mg KOH / g). .1) is reacted in xmg (x × 10 ⁻³ g), and can be calculated by the following formula: molecular weight = 56,100 ÷ x.

<Number average molecular weight and mass average molecular weight of graft polymer>
The number average molecular weight (Mn) and the mass average molecular weight (Mw) were measured by GPC (gel permeation chromatography) under the following conditions.
Apparatus: GPC-150C (manufactured by Waters)
Column: KF801-807 (manufactured by Shodex)
Temperature: 40 ° C
Solvent: THF (tetrahydrofuran)
Flow rate: 1.0 ml / min
Sample: Injection of 0.1 ml of a sample having a concentration of 0.05 to 0.6% The average number molecular weight of the toner using a molecular weight calibration curve prepared by a monodisperse polystyrene standard sample from the molecular weight distribution of the toner resin measured under the above conditions And the mass average molecular weight was calculated.

(Synthesis Example 1)
-Purification of rosin-
In a 2,000 mL distillation flask equipped with a fractionation tube, a reflux condenser, and a receiver, 1,000 g of tall rosin was added and distilled under a reduced pressure of 13.3 kPa. The distillate was collected as the main fraction. The rosin before purification was unpurified rosin A, and the main fraction obtained by distillation under reduced pressure of 13.3 kPa was purified rosin B, which was used in the following examples and comparative examples.

  Next, 20 g of each rosin was pulverized with a coffee mill (National MK-61M) for 5 seconds, and 0.5 g was measured in a headspace vial (20 mL) through a sieve having an opening of 1 mm. The headspace gas was sampled, and impurities in rosins A to B were analyzed by the headspace GC-MS method as follows. The results are shown in Table 1.

<Measurement conditions of the headspace GC-MS method>
A. Headspace sampler (manufactured by Agilent, HP7694)
Sample temperature: 200 ° C
・ Loop temperature: 200 ℃
・ Transfer line temperature: 200 ℃
・ Sample heating equilibrium time: 30 min
・ Vial pressurization gas: Helium (He)
・ Vial pressurization time: 0.3 min
・ Loop filling time: 0.03 min
-Loop equilibration time: 0.3 min
・ Injection time: 1 min

B. GC (gas chromatography) (manufactured by Agilent, HP6890)
Analytical column: DB-1 (60 m-320 μm-5 μm)
・ Carrier: Helium (He)
・ Flow conditions: 1 mL / min
・ Inlet temperature: 210 ° C
Column head pressure: 34.2 kPa
Injection mode: split
Split ratio: 10: 1
-Oven temperature conditions: 45 ° C (3min) -10 ° C / min-280 ° C (15min)

C. MS (mass spectrometry) (manufactured by Agilent, HP5973)
-Ionization method: EI (electron impact) method-Interface temperature: 280 ° C
-Ion source temperature: 230 ° C
-Quadrupole temperature: 150 ° C
・ Detection mode: Scan 29-350m / s

(Synthesis Example 2)
-Synthesis of acrylic acid-modified rosin-
In a 10-liter flask equipped with a fractionation tube, a reflux condenser, and a receiver, 6,084 g (18 mol) of purified rosin (Ts value: 76.8 ° C.) and 907.9 g (12.6) of acrylic acid were used. Mol), and the mixture was heated from 160 ° C. to 220 ° C. over 8 hours, reacted at 220 ° C. for 2 hours, and further distilled under a reduced pressure of 5.3 kPa to obtain an acrylic-modified rosin.

(Synthesis Example 3)
-Synthesis of fumaric acid-modified rosin-
In a 10 liter flask equipped with a fractionation tube, reflux condenser, and receiver, purified rosin (Ts value: 76.8 ° C.) 5,408 g (16 mol), fumaric acid 928 g (8 mol), and 0.4 g of t-butylcatechol was added, the temperature was raised from 160 ° C. to 200 ° C. over 2 hours, reacted at 200 ° C. for 2 hours, and further distilled under a reduced pressure of 5.3 kPa to obtain a fumar-modified rosin. Got. The fuma-modified rosin had a Ts value of 130.8 ° C., a glass transition point of 74.4 ° C., and a fuma modification degree of 100.

(Synthesis Example 4)
-Synthesis of maleic acid-modified rosin-
In a 10-liter flask equipped with a fractionation tube, a reflux condenser, and a receiver, purified rosin (Ts value: 76.8 ° C.) 6,084 g (18 mol) and maleic anhydride 882 g (9 mol) The mixture was heated from 160 ° C. to 220 ° C. over 8 hours, reacted at 220 ° C. for 2 hours, and then distilled under a reduced pressure of 5.3 kPa to obtain malein-modified rosin. The male-modified rosin had a Ts value of 106.2 ° C. and a maleic modification degree of 75.

(Synthesis Example 5, Synthesis Example 12, and Synthesis Example 13)
-Synthesis of polyester binder resin 1, polyester binder resin 8, and polyester binder resin 9-
Place the alcohol component shown in Table 2, the carboxylic acid component other than trimellitic anhydride, and the esterification catalyst into a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. In a nitrogen atmosphere, a polycondensation reaction was performed at 230 ° C. until the reaction rate (product water amount / theoretical product water amount × 100) reached 90%, and then the reaction was performed at 230 ° C. and 8.0 kPa for 1 hour. After cooling to 220 ° C., trimellitic anhydride is added, and after reacting at normal pressure for 1 hour, the reaction is carried out at 220 ° C. and 20 kPa until the desired softening point is reached. Polyester binder resin 8 and polyester binder resin 9 were synthesized.

(Synthesis Example 6 and Synthesis Example 8)
-Synthesis of polyester binder resin 2 and polyester binder resin 4-
The alcohol component, terephthalic acid, and esterification catalyst shown in Table 2 were placed in a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and 230 ° C. under a nitrogen atmosphere. And then subjected to a condensation polymerization reaction for 15 hours at 230 ° C. and 8.0 kPa for 1 hour. After cooling to 180 ° C., rosin B was added and reacted at 200 ° C. for 15 hours. After cooling to 180 ° C., itaconic acid was added and reacted at 200 ° C. for 8 hours. After cooling to 180 ° C., trimellitic anhydride is added, the temperature is raised to 210 ° C. over 2 hours, the reaction is carried out at 210 ° C. and 10 kPa to the desired softening point, and polyester binder resin 4 is obtained. Synthesized.

(Synthesis Example 7)
-Synthesis of polyester binder resin 3-
The alcohol component, terephthalic acid, and esterification catalyst shown in Table 2 were placed in a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and 230 ° C. under a nitrogen atmosphere. And then subjected to a condensation polymerization reaction for 15 hours at 230 ° C. and 8.0 kPa for 1 hour. After cooling to 180 ° C., rosin B was added and reacted at 200 ° C. for 15 hours. After cooling to 180 ° C., trimellitic anhydride is added, the temperature is raised to 210 ° C. over 2 hours, the reaction is carried out at 210 ° C. and 10 kPa to the desired softening point, and polyester binder resin 3 is obtained. Synthesized.

(Synthesis Examples 9 to 11)
-Synthesis of polyester binder resins 5-7-
The alcohol component shown in Table 2, the carboxylic acid component other than trimellitic anhydride, and the esterification catalyst were put into a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, After a condensation polymerization reaction at 230 ° C. for 10 hours in a nitrogen atmosphere, the reaction was performed at 230 ° C. and 8 kPa for 1 hour. After cooling to 220 ° C., trimellitic anhydride is added, and after reacting at normal pressure (101.3 kPa) for 1 hour, the reaction is carried out at 220 ° C. and 20 kPa until the desired softening point is reached. Binder resins 5 to 7 were synthesized.

(Note 1) The value in parentheses in the usage amount of the alcohol component and the carboxylic acid component is a molar ratio when the total amount of alcohol is 100 mol.
* BPA-PO: polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane * BPA-EO: polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) )propane

(Synthesis Example 14)
-Production of graft polymer W-1-
In an autoclave reaction vessel equipped with a thermometer and a stirrer, 480 parts by mass of xylene and 100 parts by mass of low molecular weight polyethylene (Sanwa Kasei Kogyo Co., Ltd. sun wax LEL-400: softening point 128 ° C.) are sufficiently dissolved. After nitrogen substitution, a mixed solution of 755 parts by mass of styrene, 100 parts by mass of acrylonitrile, 45 parts by mass of butyl acrylate, 21 parts by mass of acrylic acid, 36 parts by mass of di-t-butylperoxyhexahydroterephthalate, and 100 parts by mass of xylene. The polymerization was conducted dropwise at 170 ° C. for 3 hours, and the temperature was further maintained at this temperature for 0.5 hour. Next, the solvent was removed, and the number average molecular weight: 3,300, the mass average molecular weight: 18,000, the glass transition point: 65.0 ° C., and the SP value of the vinyl resin 11.0 (cal / cm ³ ) ^{1 / 2} graft graft polymer W-1 was obtained.

(Synthesis Example 15)
-Production of graft polymer W-2-
In an autoclave reaction vessel equipped with a thermometer and a stirrer, 450 parts by mass of xylene and 200 parts by mass of low molecular weight polypropylene (Sanyo Chemical Industries Co., Ltd., biscol 440P: softening point 153 ° C.) are sufficiently dissolved, and after nitrogen replacement , 280 parts by mass of styrene, 520 parts by mass of methyl methacrylate, 32.3 parts by mass of di-t-butylperoxyhexahydroterephthalate, and 120 parts by mass of xylene were dropped at 150 ° C. for 2 hours to polymerize, This temperature was maintained for 1 hour. Next, the solvent was removed, and the number average molecular weight: 3,300, the mass average molecular weight: 16,000, the glass transition point: 58.8 ° C., and the SP value of the vinyl resin 10.2 (cal / cm ³ ) ^{1 / 2} graft polymer W-2 was obtained.

(Synthesis Example 16)
-Production of graft polymer W-3-
In an autoclave reaction vessel equipped with a thermometer and a stirrer, 450 parts by mass of xylene, 150 parts by mass of a low molecular weight polypropylene and a low molecular weight polyethylene mixture (Licocene 1302 manufactured by Clariant, softening point 78.9 ° C.) were sufficiently dissolved and dissolved. After substitution, a mixed solution of 20 parts by mass of styrene, 460 parts by mass of methyl methacrylate, 140 parts by mass of acrylonitrile, 35 parts by mass of di-t-butylperoxyhexahydroterephthalate, and 120 parts by mass of xylene was dropped at 150 ° C. for 2 hours. The resulting mixture was then polymerized and held at this temperature for 1 hour. Subsequently, the solvent was removed, and the number average molecular weight: 2,400, the mass average molecular weight: 14,000, the glass transition point: 88.5 ° C., and the SP value of the vinyl resin 11.5 (cal / cm ³ ) ^{1 / 2} graft polymer W-3 was obtained.

Example 1
-Production of Toner 1-
100 parts by mass of the binder resin shown in Example 1 of Table 3, 6 parts by mass of carbon black (“MOGUL L”, manufactured by Cabot), 5 parts by mass of paraffin wax (“HNP-9”, manufactured by Nippon Seiwa Co., Ltd.) , Graft polymer W-1; 2 parts by mass, and 1 part by mass of a negatively chargeable charge control agent (“Bontron S-34”, manufactured by Orient Chemical Industry Co., Ltd.) After being sufficiently stirred and mixed, the mixture was kneaded with a twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), rolled with a cooled two roll, and then cooled on a steel belt. Here, the kneading was performed such that the temperature of the kneaded product at the exit of the twin-screw extruder was about 120 ° C. Next, the mixture was pulverized by a jet mill, and the particle size distribution was adjusted by air classification to prepare a toner base having a volume average particle size of about 7 μm.
To 100 parts by mass of the obtained toner base, 1.0 part by mass of “Aerosil R-972” (manufactured by Nippon Aerosil Co., Ltd.) as an external additive was added and mixed with a Henschel mixer to prepare toner 1.

-Fabrication of magnetic carrier-
A mixture having the following composition was dispersed with a homomixer for 20 minutes to prepare a coat layer forming solution. A magnetic carrier A was prepared by coating this coating layer forming solution on the surface of 1,000 parts by mass of spherical magnetite having an average particle diameter of 50 μm using a fluid bed type coating apparatus.
[Composition of coating layer forming solution]
・ Silicone resin (organostraight silicone): 100 parts by mass ・ Toluene: 100 parts by mass ・ γ- (2-aminoethyl) aminopropyltrimethoxysilane: 5 parts by mass ・ Carbon black ... 10 parts by mass

-Production of two-component developer 1-
4 parts by mass of the toner 1 and 96 parts by mass of the magnetic carrier A were mixed with a tumbler shaker mixer (Shinmaru Enterprises) to prepare a two-component developer 1.

  The toner 1 and the two-component developer 1 were used to evaluate low-temperature fixability, hot offset property, filming property, image density stability, storage stability, and odor as follows. The results are shown in Table 3. As shown in Table 3, all were good results.

<Low temperature fixability>
As the fixing device 6 in the image forming apparatus shown in FIG. 1, a fixing roller in which a Teflon (registered trademark) coat is applied to an aluminum core metal having a diameter of 40 mm and a wall thickness of 0.4 mm, and a 650 W halogen heater is incorporated therein, and a diameter A fixing device comprising a roller provided with a foamed silicone rubber layer having a thickness of 6 mm on a 30 mm aluminum core and further having a PFA layer having a thickness of 0.1 mm was used. A developer is put into this image forming apparatus, and it is driven at a linear speed of 230 mm / sec. Using a type 6200 paper manufactured by Ricoh Co., Ltd., the fixing set temperature is raised by 5 ° C., and images obtained at the respective fixing temperatures are obtained. The degree of soiling of the cotton cloth due to the toner rubbed with the cotton cloth was measured as reflection density with a spectrometer (938 Spectrodensitometer, manufactured by X-Light Co., Ltd.) at five locations, and the average value was 0.3 The lowest fixing temperature, which is the following, was set as the minimum fixing temperature, and the low-temperature fixing property was evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
A: Minimum fixing temperature is less than 160 ° C. O: Minimum fixing temperature is 160 ° C. or higher and lower than 170 ° C. X: Minimum fixing temperature is 170 ° C. or higher.

<Hot offset property>
Using the same equipment and conditions as for low-temperature fixability, raise the fixing temperature by 5 ° C, visually determine the presence or absence of an offset in the image obtained at each fixing temperature, and offset if an offset image is seen in the image. The offset temperature was evaluated according to the following evaluation criteria as the generated temperature.
〔Evaluation criteria〕
A: Offset generation temperature is 220 ° C. or higher. ○: Offset generation temperature is 200 ° C. or higher and lower than 220 ° C. Δ: Offset generation temperature is 180 ° C. or higher and lower than 200 ° C. ×: Offset generation temperature is lower than 180 ° C.

<Filming properties>
A developer was put in the image forming apparatus shown in FIG. 1, and an Ricoh type 6200 paper was used to form an image at a linear speed of 230 mm / sec and a printing rate of 7%, and a running test was performed. The filming on the photoconductor after 10,000 sheets, 30,000 sheets, 50,000 sheets, and 100,000 sheets, and the presence or absence of abnormal images (halftone density unevenness) due to filming were evaluated. The occurrence of filming is disadvantageous as the number of running sheets increases, and filming properties were evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
◎: Filming does not occur even with 100,000 sheets ○: Filming does not occur even with 50,000 sheets △: Filming does not occur even with 30,000 sheets ×: Filming occurs with 10,000 sheets

<Image density stability>
A developer is put in the image forming apparatus shown in FIG. 1, and an image is formed one by one using a Ricoh Co., Ltd. type 6200 paper with a linear velocity of 230 mm / sec. A running test was performed. The image density of the black solid image after 50, 100, 150, and 200 sheets was measured. The decrease in image density is disadvantageous as the number of running sheets increases, and image density stability was evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
A: Image density decrease is 0.1 or less even with 200 sheets. O: Image density decrease is 0.1 or less even with 150 sheets. Δ: Image density decrease is 0.1 or less even with 100 sheets. Even with 50 sheets, the decrease in image density is 0.1 or more.

<Presence of odor during fixing test and filming test>
The presence or absence of toner odor during the fixing test and filming test was evaluated according to the following criteria.
〔Evaluation criteria〕
○: Odor is not felt in any test ×: Odor was felt in at least any test.
<Storability of toner>
4 g of toner was placed in an open cylindrical container having a diameter of 5 cm and a height of 2 cm, and left for 72 hours in an environment of a temperature of 45 ° C. and a relative humidity of 65%. After leaving, the container containing the toner was shaken lightly, and the presence or absence of toner aggregation was visually observed, and the storage stability was evaluated according to the following evaluation criteria.
〔Evaluation criteria〕
A: No toner aggregation is observed. O: One to two toner aggregation particles are observed. Δ: Three to five toner aggregation particles are observed. X: Six toner aggregation particles are observed. Observed above

( Reference Example 2)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the addition amount of the graft polymer W-1 was reduced to 0.5 parts by mass. Went. The results are shown in Table 3. Although the hot offset property was better than that of Example 1, the filming property and the image density stability were slightly lower than those of Example 1.

(Example 3)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the addition amount of the graft polymer W-1 was increased to 7.5 parts by mass, and the same evaluation as in Example 1 was performed. Went. The results are shown in Table 3. Although the filming property and the image density stability were better than those of Example 1, the hot offset property was slightly lower than that of Example 1.

Example 4
A toner and a developer were prepared in the same manner as in Example 1 except that the graft polymer W-1 was changed to the graft polymer W-2 in the toner formulation of Example 1, and the same evaluation as in Example 1 was performed. It was. The results are shown in Table 3. As in Example 1, all of the low-temperature fixability, hot offset property, filming property, image density stability, storage stability, and odor were good results.

(Example 5)
A toner and a developer were prepared in the same manner as in Example 1 except that the graft polymer W-1 was changed to the graft polymer W-3 in the toner formulation of Example 1, and the same evaluation as in Example 1 was performed. It was. The results are shown in Table 3. As in Example 1, all of the low-temperature fixability, hot offset property, filming property, image density stability, storage stability, and odor were good results.

(Example 6)
A toner and a developer were prepared in the same manner as in Example 1 except that in the toner formulation of Example 1, polyester-based binder resin 2 containing 1,2-propanediol was used instead of polyester-based binder resin 1. Then, the same evaluation as in Example 1 was performed. The results are shown in Table 3. The low-temperature fixability was better than that of Example 1, and the hot offset property, filming property, image density stability, storage stability, and odor were all good results.

(Example 7)
In the toner formulation of Example 1, 40 parts by mass of polyester binder resin 3 which is a low softening point resin containing 1,2-propanediol instead of polyester binder resin 1 and 1,2-propanediol A toner and a developer were prepared in the same manner as in Example 1 except that 60 parts by mass of the polyester-based binder resin 4 which is a high softening point resin contained therein was used, and the same evaluation as in Example 1 was performed. The results are shown in Table 3. The results showed better low-temperature fixing properties and hot offset properties than Example 1, and all the filming properties, image density stability, storage stability, and odor were good results.

(Example 8)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that polyester-based binder resin 5 containing acrylic acid-modified rosin was used instead of polyester-based binder resin 1. Evaluation similar to Example 1 was performed. The results are shown in Table 3. The hot offset property, storage property, filming property, and image density stability were better than those of Example 1, and both the low-temperature fixability and odor were good results. .

Example 9
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the polyester binder resin 6 containing fumaric acid-modified rosin was used instead of the polyester binder resin 1. Evaluation similar to Example 1 was performed. The results are shown in Table 3. The hot offset property, the storage property, the filming property, and the image density stability, which are better than those of Example 1, were exhibited, and the low-temperature fixability and odor were also good.
(Example 10)
In the toner formulation of Example 1, the toner is the same as in Example 1 except that instead of the polyester binder resin 1, a polyester binder resin 7 containing 1,2-propanediol and maleic acid-modified rosin is used. A developer was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3. The results showed better low-temperature fixability, hot offset properties, storage stability, filming properties, and image density stability than Example 1, and the odor was also good.

( Reference Example 11)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the addition amount of the graft polymer W-1 was increased to 10 parts by mass, and the same evaluation as in Example 1 was performed. It was. The results are shown in Table 3. Although the filming property and the image density stability were improved as compared with Example 1, the hot offset property was lower than that of Example 1.

(Comparative Example 1)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the graft polymer was not used, and the same evaluation as in Example 1 was performed. The results are shown in Table 3. Although the hot offset property was improved as compared with Example 1, the filming property and the image density stability were lower than those of Example 1.

(Comparative Example 2)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that the polyester-based binder resin 8 containing unpurified rosin was used instead of the polyester-based binder resin 1. Evaluation similar to Example 1 was performed. Although the result was shown in Table 3, although hot offset property improved from Example 1, the preservability and odor fell.

(Comparative Example 3)
In the toner formulation of Example 1, a toner and a developer were prepared in the same manner as in Example 1 except that a polyester-based binder resin 9 not containing rosin was used in place of the resin 1, and evaluation similar to that in Example 1 was made. Went. The results are shown in Table 3. Although the hot offset property, the storage property and the odor were good, the low temperature fixability was not obtained.

From the results of Table 3, Comparative Example 1 containing no graft polymer is inferior in filming property and image density stability, and Comparative Example 2 using unpurified rosin is inferior in storage stability and feels odor. It was. Since Comparative Example 3 did not use rosin, the low-temperature fixability was inferior. In addition, it is recognized that the toners of Examples 1 and 3 to 10 have good results in any of low-temperature fixability, hot offset property, filming property, image density stability, storage stability, and odor. It is done.

  The toner and the image forming apparatus of the present invention are excellent in low-temperature fixing property and anti-offset property, do not cause filming on the photoreceptor, and have a stable image density against changes in image area and image output conditions. Therefore, it is possible to form a high-quality image over a long period of time, and further, no odor is generated at the time of fixing. Therefore, electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method, etc. It is suitably used for image development and the like.

FIG. 1 is a schematic configuration diagram of a main part showing an example of an image forming apparatus (copier) according to the present invention. FIG. 2 is a schematic configuration diagram showing the developing device of the copying machine of FIG.

Explanation of symbols

1 Electrostatic latent image carrier (photosensitive drum)
2 Charging device 3 Exposure device 4 Developing device 5 Transfer device 6 Fixing device 7 Cleaning member 40 Developer 43 Developing sleeve 44 Magnet roller 45 Doctor blade 46 Power supply 47 Developer leveling member

Claims (6)

A binder resin, a colorant, and poly olefin waxes, and long-chain hydrocarbon waxes of the release agent comprising at least one polyethylene, polymethylene, polypropylene, or ethylene / propylene copolymer and the thermal degradation products At least one polyolefin resin selected from the group consisting of at least one selected from styrene, alkyl (meth) acrylates, and (meth) acrylonitrile, and an SP value of 10.0. a graft polymer grafted with vinyl resin is 11.5, containing,
The binder resin comprises an alcohol component of either an aliphatic dialcohol or an alkylene oxide adduct of bisphenol A, a purified rosin purified by distillation, an aliphatic dicarboxylic acid or anhydride thereof, an aromatic dicarboxylic acid or anhydrides, alicyclic dicarboxylic acids or their anhydrides, trivalent or higher polycarboxylic acid or its anhydride, and condensed with at least one, the the number of carbon atoms is selected from any of 1 to 3 alkyl esters Contains a polyester resin obtained by polymerization,
Wherein of the polyester resin 100 parts by weight, the graft polymer 2.0 parts by mass to 10 parts by mass seen including,
10 to 150 parts by mass of the graft polymer is included with respect to 100 parts by mass of the release agent.
Toner characterized by the above.   The toner according to claim 1, wherein the alcohol component contains 1,2-propanediol in an amount of 65 mol% or more of the divalent alcohol component.   The polyester resin contains a polyester resin (A) having a softening point Tm (A) of 120 ° C. or higher and 160 ° C. or lower and a polyester resin (B) having a softening point Tm (B) of 80 ° C. or higher and lower than 120 ° C. The toner according to claim 1.   The toner according to claim 1, wherein the purified rosin is modified with at least one of acrylic acid, fumaric acid, and maleic acid.   The toner according to any one of claims 1 to 4, wherein the polyolefin resin has a softening point of 70 to 150 ° C. An electrostatic latent image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image carrier, and the toner according to any one of claims 1 to 5 And developing means for forming a visible image by developing the 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. An image forming apparatus.