JP6353356B2 - Toner for electrophotography - Google Patents

Description

  The present invention relates to an electrophotographic toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, and the like, and a method for producing the same.

  From the viewpoint of increasing the speed and energy saving of a printing apparatus, a toner having excellent low-temperature fixability is required. However, if the softening point or glass transition point of the toner is designed to be low in order to improve the low-temperature fixability, there is a problem that the storage stability is lowered. In order to achieve both low-temperature fixability and storage stability, toners using both a crystalline composite resin and an amorphous composite resin have been developed.

Patent Document 1 includes a raw material monomer of a crystalline polyester containing a diol having 8 to 12 carbon atoms and a dicarboxylic acid compound having 10 to 12 carbon atoms and having a total content of 80 mol% or more, and an addition polymerization resin. By polymerizing 3 to 15 parts by weight of the crystalline polyester raw material monomer and the addition polymerization resin raw material monomer with respect to 100 parts by weight of the raw material monomer and the raw material monomer of the addition polymerization resin. Crystalline hybrid resin (1-2) containing a crystalline polyester component and an addition polymerization resin component obtained,
A raw material monomer of an amorphous polycondensation resin containing an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound, a raw material monomer of an addition polymerization resin, and 100 parts by weight of the raw material monomer of the addition polymerization resin 2-15 parts by weight of an amorphous polycondensation resin component and an addition polycondensation resin component obtained by polymerizing a compound capable of reacting with any of the addition monomer monomers. Amorphous hybrid resin containing a polymeric resin component (2-2)
A toner for developing an electrostatic image comprising a binder resin comprising a weight ratio of the crystalline hybrid resin (1-2) to the amorphous hybrid resin (2-2) (crystal An electrostatic charge image developing toner is disclosed wherein the conductive hybrid resin (1-2) / amorphous hybrid resin (2-2)) is 1/99 to 40/60.

JP2013-109237A

  The present inventors combined low-temperature fixability and durability by combining a crystalline composite resin obtained using a long-chain aliphatic monomer and an amorphous composite resin obtained using an aromatic dicarboxylic acid compound. However, it has been found that when these resins are combined, paper wrapping easily occurs during toner fixing.

  The present invention relates to an electrophotographic toner that has excellent low-temperature fixability and durability, and suppresses paper wrapping during fixing.

The present invention
[1] An electrophotographic toner containing a crystalline resin, an amorphous resin, and a release agent,
The crystalline resin is obtained by polycondensation of an alcohol component containing an aliphatic diol having 9 to 14 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms. Containing a crystalline composite resin C containing a condensation resin component and a styrene resin component;
Amorphous composite resin A, wherein the amorphous resin comprises a polycondensation resin component obtained by polycondensation of an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and a styrene resin component Containing
An electrophotographic toner in which the average circularity of the toner is 0.940 or more and the content of particles having a particle diameter of 3 μm or less in the toner is 5.0% by number or less; and [2] Step 1: Crystalline Composite Resin C, a step of melt-kneading a toner component containing an amorphous composite resin A and a release agent using an open roll type kneader, and a step 2: a step of pulverizing and classifying the obtained kneaded product, The present invention relates to the method for producing an electrophotographic toner according to [1].

  The toner for electrophotography of the present invention is excellent in low-temperature fixability and durability, and has an excellent effect that paper winding at the time of fixing is suppressed not only at the initial printing stage but also during continuous printing.

  The electrophotographic toner of the present invention (hereinafter also simply referred to as “toner”) contains a crystalline resin, an amorphous resin, and a release agent, and a long-chain aliphatic monomer is used as the crystalline resin. The crystalline composite resin C containing a polycondensation resin component, the amorphous resin contains an amorphous composite resin A containing a polycondensation resin component using an aromatic dicarboxylic acid compound, and the average circularity of the toner The fine powder content is adjusted within a predetermined range.

The reason why the electrophotographic toner of the present invention is excellent in low-temperature fixability and durability and suppresses paper wrapping during fixing is not clear, but can be considered as follows.
Usually, the problem of winding the paper at the time of fixing hardly occurs in the toner. This is because the dispersibility of the release agent is low in the normal toner, and the toner is pulverized at the interface of the release agent. This is probably because the toner fine powder generated sometimes contains a large amount of the release agent. Further, Patent Document 1 manufactured using a twin screw extruder does not consider the winding of the paper at the time of fixing.
On the other hand, when the crystalline composite resin C and the amorphous composite resin A are used in combination, the dispersibility of the release agent is too good, so that the low temperature fixability and durability are excellent. It is considered that the amount of the mold agent decreases, and the problem of winding of the paper occurs at the time of fixing. In particular, when an open roll type kneader having a high kneading force is used, the release agent is finely dispersed by the styrene resin component of the crystalline composite resin C and the amorphous composite resin A. it is conceivable that.
Therefore, in the present invention, the winding at the time of fixing can be suppressed by setting the average circularity of the toner and the amount of fine powder in the toner within a specific range. That is, by controlling the amount of fine powder in the toner, paper wrapping at the time of initial fixing can be suppressed, and by further increasing the average circularity of the toner, generation of toner fine powder generated during continuous printing is controlled, It is considered that the effect of suppressing paper wrapping can be maintained even during continuous printing.

  In the present invention, the crystallinity of the resin is represented by the crystallinity index defined by the ratio between the softening point and the maximum endothermic peak temperature measured by a differential scanning calorimeter, that is, the value of [softening point / maximum endothermic peak temperature]. . The crystalline resin is a resin having a crystallinity index of 0.6 to 1.4, preferably 0.7 to 1.2, more preferably 0.9 to 1.2, and the amorphous resin has a crystallinity index of more than 1.4 or less than 0.6, preferably Is a resin of more than 1.5, 0.5 or less, more preferably 1.6 or more and 0.5 or less. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers, production conditions (for example, reaction temperature, reaction time, cooling rate) and the like. The highest endothermic peak temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks. In the crystalline resin, the highest endothermic peak temperature is the melting point. In the present invention, the term “resin” means both a crystalline resin and an amorphous resin.

  The crystalline composite resin C contained in the crystalline resin comprises an alcohol component containing an aliphatic diol having 9 to 14 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms. A resin comprising a polycondensation resin component obtained by polycondensation and a styrene resin component.

  Examples of the polycondensation resin component include polyester, polyester / polyamide, and the like. From the viewpoint of improving toner durability and low-temperature fixability, polyester is preferable.

  The polyester is preferably obtained by polycondensation of an alcohol component containing a divalent or higher alcohol and a carboxylic acid component containing a divalent or higher carboxylic acid compound.

  The number of carbon atoms of the aliphatic diol contained in the alcohol component of the polycondensation resin component is 9 or more from the viewpoint of low-temperature fixability, preferably 10 or more, more preferably 12 or more, and 14 or less from the viewpoint of durability. And 12 is preferred.

  Examples of the aliphatic diol having 9 to 14 carbon atoms include 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, and the like. Α, ω-linear alkanediol is preferable from the viewpoint of enhancing the low-temperature fixability and durability of the toner, and one or two selected from 1,10-decanediol and 1,12-dodecanediol Species are more preferred, and 1,12-dodecanediol is even more preferred.

  The content of the aliphatic diol having 9 to 14 carbon atoms is preferably 70 mol% or more, more preferably 70% by mole or more in the total amount of the dihydric or higher alcohol of the alcohol component from the viewpoint of improving the low-temperature fixability and durability of the toner. Is 90 mol% or more, more preferably 95 mol% or more, preferably 100 mol% or less, more preferably substantially 100 mol%, more preferably 100 mol%. Further, the proportion of one kind of the aliphatic diol having 9 to 14 carbon atoms in the dihydric or higher alcohol of the alcohol component is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol%. It is preferable to occupy at least mol%, more preferably at least 95 mol%, preferably at most 100 mol%, more preferably substantially 100 mol%, more preferably 100 mol%.

  The alcohol component may contain a polyhydric alcohol other than an aliphatic diol having 9 to 14 carbon atoms, and an aromatic diol such as an alkylene oxide adduct of bisphenol A; glycerin, pentaerythritol, trimethylolpropane, Examples include trivalent or higher alcohols such as sorbitol and 1,4-sorbitan.

  The carbon number of the aliphatic dicarboxylic acid compound contained in the carboxylic acid component of the polycondensation resin is 9 or more from the viewpoint of low-temperature fixability, preferably 10 or more, and 14 or less from the viewpoint of durability, 12 The following is preferable, and 10 is more preferable.

  Examples of the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms include azelaic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid and the like. From the viewpoint of improving the durability of the toner, sebacic acid and dodecanedioic acid are used. One or two selected are preferable, and sebacic acid is more preferable. The dicarboxylic acid compound refers to dicarboxylic acid, its anhydride, and alkyl ester having 1 to 3 carbon atoms, and among these, dicarboxylic acid is preferable. Moreover, the carbon number of the aliphatic dicarboxylic acid compound is the number of carbons including the dicarboxylic acid part, and does not include the alkyl ester part.

  The carboxylic acid component may contain a polyvalent carboxylic acid compound other than the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms. Examples of the polyvalent carboxylic acid compound include oxalic acid, malonic acid, and maleic acid. , Fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, aliphatic dicarboxylic acids such as succinic acid substituted with an alkyl group having 1 to 30 carbon atoms or an alkenyl group having 2 to 30 carbon atoms Trivalent or more of aromatic dicarboxylic acid such as acid, phthalic acid, isophthalic acid, terephthalic acid, alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid, trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, etc. Aromatic carboxylic acids, and acid anhydrides thereof, alkyl esters having 1 to 3 carbon atoms, and the like.

  The content of the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms is preferably 70% of the total amount of the divalent or higher carboxylic acid compound in the carboxylic acid component, from the viewpoint of improving the low-temperature fixability and durability of the toner. It is at least mol%, more preferably at least 90 mol%, even more preferably at least 95 mol%, preferably at most 100 mol%, more preferably substantially at 100 mol%, still more preferably at 100 mol%.

  The raw material monomer of the polycondensation resin component of the crystalline composite resin C is a monovalent aliphatic carboxylic acid compound having 8 to 22 carbon atoms and a monovalent carbon having 8 to 22 carbon atoms from the viewpoint of low-temperature fixability. It is preferable to contain at least one of the aliphatic alcohols.

  From the viewpoint of low-temperature fixability, the number of carbon atoms of the monovalent aliphatic alcohol and the monovalent aliphatic carboxylic acid compound is preferably 8 or more, more preferably 12 or more, further preferably 14 or more, and further preferably 16 or more. Further, from the viewpoint of productivity, it is preferably 22 or less, more preferably 20 or less, and further preferably 18 or less.

  Examples of the monovalent aliphatic alcohol having 8 to 22 carbon atoms include aliphatic alcohols such as palmityl alcohol, stearyl alcohol, and behenyl alcohol. Among these, stearyl alcohol is preferable.

  Examples of the monovalent aliphatic carboxylic acid compound having 8 to 22 carbon atoms include aliphatic carboxylic acid compounds such as palmitic acid, stearic acid, and behenic acid. Among these, stearic acid is preferable.

The total content of the monovalent aliphatic alcohol having 8 to 22 carbon atoms and the monovalent aliphatic carboxylic acid compound having 8 to 22 carbon atoms in the raw material monomer of the polycondensation resin component of the crystalline composite resin C That is, in the total amount of the alcohol component and the carboxylic acid component, from the viewpoint of low-temperature fixability, 1 mol% or more is preferable, 2 mol% or more is more preferable, and 3 mol% or more is more preferable. Further, from the viewpoint of durability, 12 mol% or less is preferable, 10 mol% or less is more preferable, 8 mol% or less is more preferable, and 6 mol% or less is more preferable.

  Among the total number of moles of the carboxylic acid component and the alcohol component that are the raw material components of the polycondensation resin component, the total number of the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms and the aliphatic diol having 9 to 14 carbon atoms The number is preferably 88 mol% or more, more preferably 90 mol% or more, still more preferably 92 mol% or more, and still more preferably, from the viewpoint of improving the crystallinity of the composite resin and improving the low-temperature fixability and durability of the toner. Is 94 mol% or more. Further, it is preferably 99 mol% or less, more preferably 98 mol% or less, and still more preferably 97 mol% or less.

  The total number of moles of the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms and the aliphatic diol having 9 to 14 carbon atoms is selected from the viewpoint of improving the low-temperature fixability and durability of the toner. In the total number of moles of the divalent or higher carboxylic acid compound in the carboxylic acid component as the raw material component and the divalent or higher alcohol in the alcohol component, preferably 80 mol% or more, more preferably 90 mol% or more, even more preferably Is 95 mol% or more, preferably 100 mol% or less, more preferably substantially 100 mol%, and still more preferably 100 mol%.

  The equivalent ratio (COOH group / OH group) of the carboxylic acid component and the alcohol component in the polycondensation resin component is preferably 0.70 or more, more preferably 0.75 or more, from the viewpoint of adjusting the softening point of the composite resin. , Preferably 1.10 or less, more preferably 1.05 or less.

  The polycondensation reaction of the raw material monomer of the polycondensation resin component is carried out in an inert gas atmosphere at a temperature of about 120 ° C. to 200 ° C. in the presence of an esterification catalyst, a polymerization inhibitor, etc. as necessary. be able to. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropylate bistriethanolamate. Examples of the catalyst include gallic acid. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1.5 parts by mass or less, more preferably 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Preferably it is 1.0 mass part or less. The amount of the esterification promoter used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass or less, with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less.

  As a raw material monomer for the styrene-based resin component, at least styrene or styrene derivatives such as α-methylstyrene and vinyltoluene (hereinafter, styrene and styrene derivatives are collectively referred to as “styrene compound”) is used.

  The content of the styrene compound is preferably 70% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass in the raw material monomer of the styrene resin component, from the viewpoint of improving the low-temperature fixability and durability of the toner. % Or more, preferably 100 mol% or less, more preferably substantially 100% by mass, still more preferably 100% by mass.

  Raw material monomers for styrene resin components used in addition to styrene compounds include (meth) acrylic acid alkyl esters; ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; and halovinyls such as vinyl chloride. Vinyl esters such as vinyl acetate and vinyl propionate; ethylenic monocarboxylic esters such as dimethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl pyrrolidone N-vinyl compounds such as

  The raw material monomer of the styrene resin component used in addition to the styrene compound can be used in combination of two or more. In the present specification, “(meth) acrylic acid” means acrylic acid and / or methacrylic acid.

  Among the raw material monomers for the styrene resin component used in addition to the styrene compound, (meth) acrylic acid alkyl esters are preferred from the viewpoint of improving the low-temperature fixability of the toner. In view of the above, the carbon number of the alkyl group in the (meth) acrylic acid alkyl ester is preferably 1 or more, more preferably 8 or more, and preferably 22 or less, more preferably 18 or less. In addition, carbon number of this alkyl ester means carbon number derived from the alcohol component which comprises ester.

  Specific examples of (meth) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (iso or tertiary ) Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (iso) octyl (meth) acrylate, (iso) decyl (meth) acrylate, (iso) stearyl (meth) acrylate, and the like. Here, “(iso or tertiary)” and “(iso)” mean that both of these groups are present and not present, and when these groups are not present Indicates normal. Further, “(meth) acrylate” indicates that both acrylate and methacrylate are included.

  From the viewpoint of improving the low-temperature fixability of the toner, the content of the (meth) acrylic acid alkyl ester is preferably 30% by mass or less, more preferably 20% by mass or less, and still more preferably, in the raw material monomer of the styrene resin component. It is 10 mass% or less, Preferably it is 0 mass% or more.

  The addition polymerization reaction of the raw material monomer of the styrenic resin component can be carried out by a conventional method, for example, in the presence of a polymerization initiator such as dicumyl peroxide, a crosslinking agent, etc., in the presence of an organic solvent or in the absence of a solvent. The temperature condition is preferably 110 ° C. or higher, more preferably 140 ° C. or higher, and preferably 200 ° C. or lower, more preferably 170 ° C. or lower.

  When an organic solvent is used in the addition polymerization reaction, xylene, toluene, methyl ethyl ketone, acetone or the like can be used. The amount of the organic solvent used is preferably 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the raw material monomer of the styrene resin component.

  From the viewpoint of improving the low-temperature fixability and durability of the toner, the crystalline composite resin C, in addition to the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component, further contains the raw material monomer of the polycondensation resin component And a resin (hybrid resin) obtained by using both reactive monomers capable of reacting with any of the raw material monomers of the styrene resin component. Therefore, when the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component are polymerized to obtain the crystalline composite resin C, the polycondensation reaction and / or the addition polymerization reaction are carried out in the presence of both reactive monomers. It is preferable to carry out with. Thereby, the crystalline composite resin C becomes a resin (hybrid resin) in which the polycondensation resin component and the styrene resin component are bonded via the structural unit derived from both reactive monomers, and the polycondensation resin component and the styrene resin are combined. The resin component is more finely and uniformly dispersed.

  That is, from the viewpoint of improving low-temperature fixability and durability of the toner, the crystalline composite resin C is (i) an alcohol component containing an aliphatic diol having 9 to 14 carbon atoms and a fat having 9 to 14 carbon atoms. A raw material monomer for a polycondensation resin component, (b) a raw material monomer for a styrene resin component, and (c) a raw material monomer for a polycondensation resin component, and a styrene resin. A resin obtained by polymerizing an amphoteric monomer capable of reacting with any of the component raw material monomers is preferred.

  As the both reactive monomers, at least one functional group selected from the group consisting of a hydroxyl group, a carboxy group, an epoxy group, a primary amino group and a secondary amino group in the molecule, preferably a hydroxyl group and / or A compound having a carboxy group, more preferably a carboxy group, and an ethylenically unsaturated bond is preferred. By using such a bireactive monomer, the dispersibility of the resin to be a dispersed phase can be further improved. The both reactive monomers are preferably at least one selected from the group consisting of acrylic acid, methacrylic acid, fumaric acid, maleic acid and maleic anhydride, but from the viewpoint of reactivity of polycondensation reaction and addition polymerization reaction Therefore, acrylic acid, methacrylic acid or fumaric acid is more preferable. However, when used with a polymerization inhibitor, a polyvalent carboxylic acid compound having an ethylenically unsaturated bond such as fumaric acid functions as a raw material monomer for the polycondensation resin component. In this case, fumaric acid or the like is not a bireactive monomer but a raw material monomer for a polycondensation resin component.

The amount of the both reactive monomers used is preferably 1 mol or more, more preferably 2 mol or more, based on 100 mol of the total of the alcohol components of the polycondensation resin component, from the viewpoint of low-temperature fixability. From the viewpoint of enhancing the dispersibility of the component and the polycondensation resin component and improving the durability of the toner, the amount is preferably 30 mol or less, more preferably 20 mol or less, and even more preferably 10 mol or less.
In addition, the amount of the both reactive monomers used is preferably 1 part by mass or more, more preferably 2 parts by mass or more, with respect to a total of 100 parts by mass of the raw material monomers of the styrene resin component, from the viewpoint of low-temperature fixability. From the viewpoint of enhancing the dispersibility of the styrene resin component and the polycondensation resin component and improving the durability of the toner, preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less. It is. Here, the polymerization initiator is included in the total of the raw material monomers of the styrene resin component.

  Specifically, the hybrid resin obtained using the both reactive monomers is preferably produced by the following method. Both reactive monomers are preferably used in the addition polymerization reaction together with the raw material monomer of the styrenic resin component from the viewpoint of improving the durability of the toner and improving the low temperature fixability and heat resistant storage stability of the toner.

(i) A method of performing a step (B) of an addition polymerization reaction with a raw material monomer of a styrene resin component and an amphoteric monomer after the step (A) of the polycondensation reaction with the raw material monomer of the polycondensation resin component. The step (A) is carried out under reaction temperature conditions suitable for the polycondensation reaction, the reaction temperature is lowered, and the step (B) is carried out under temperature conditions suitable for the addition polymerization reaction. It is preferable that the raw material monomer and the both reactive monomers of the styrene resin component are added to the reaction system at a temperature suitable for the addition polymerization reaction. Both reactive monomers undergo an addition polymerization reaction and also a polycondensation resin component.
After the step (B), the reaction temperature is raised again, and if necessary, a raw material monomer or the like of a polycondensation resin component having a valence of 3 or more that becomes a crosslinking agent is added to the polymerization system, and the polycondensation reaction in the step (A) And the reaction with both reactive monomers can be further advanced.

(ii) Method of performing the step (A) of the polycondensation reaction with the raw material monomer of the polycondensation resin component after the step (B) of the addition polymerization reaction with the raw material monomer of the styrene resin component and the amphoteric monomer. The step (B) is carried out under reaction temperature conditions suitable for the addition polymerization reaction, the reaction temperature is raised, and the polycondensation reaction in step (A) is carried out under temperature conditions suitable for the polycondensation reaction. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.
The raw material monomer of the polycondensation resin component may be present in the reaction system during the addition polymerization reaction, or may be added to the reaction system under temperature conditions suitable for the polycondensation reaction. In the former case, the progress of the polycondensation reaction can be controlled by adding an esterification catalyst at a temperature suitable for the polycondensation reaction.

(iii) The polycondensation resin component raw material monomer polycondensation reaction step (A) and the styrene resin component raw material monomer and bi-reactive monomer addition polymerization reaction step (B) proceed in parallel. In this method, the step (A) and the step (B) are performed in parallel under the reaction temperature conditions suitable for the addition polymerization reaction, the reaction temperature is increased, and the temperature suitable for the polycondensation reaction. Under the conditions, it is preferable that a raw material monomer of a tri- or higher-valent polycondensation resin component serving as a cross-linking agent is added to the polymerization system as necessary, and the polycondensation reaction in step (A) is further performed. At that time, under a temperature condition suitable for the polycondensation reaction, a radical polymerization inhibitor can be added to advance only the polycondensation reaction. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.

  In the method (i), a prepolymerized polycondensation resin may be used in place of the step (A) for performing the polycondensation reaction. In the above method (iii), when the reaction is carried out under the conditions in which the step (A) and the step (B) proceed in parallel, a styrene resin is contained in the mixture containing the raw material monomer of the polycondensation resin component. A mixture containing the component raw material monomers can also be dropped and reacted.

  The methods (i) to (iii) are preferably performed in the same container.

  The mass ratio of the polycondensation resin component to the styrene resin component (polycondensation resin component / styrene resin component) in the crystalline composite resin C is preferably 55/45 or more from the viewpoint of low-temperature fixability, 30 or more is more preferable, and 80/20 or more is more preferable. Further, from the viewpoint of durability, 95/5 or less is preferable, 92/8 or less is more preferable, and 90/10 or less is more preferable. In the above calculation, the mass of the polycondensation resin component is an amount obtained by subtracting the amount of reaction water (calculated value) dehydrated by the polycondensation reaction from the mass of the raw material monomer of the polycondensation resin used. The amount of both reactive monomers is included in the amount of raw material monomers of the polycondensation resin component. The amount of the styrene resin component is the amount of the raw material monomer of the styrene resin component, and includes the amount of the polymerization initiator.

  The softening point of the crystalline composite resin C is preferably 60 ° C. or higher, more preferably 70 ° C. or higher, further preferably 75 ° C. or higher, and more preferably 78 ° C. or higher, from the viewpoint of improving the durability of the toner. Further, from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 140 ° C. or lower, more preferably 120 ° C. or lower, still more preferably 110 ° C. or lower, and further preferably 100 ° C. or lower.

  The melting point (maximum endothermic peak temperature) of the crystalline composite resin C is preferably 55 ° C. or higher, more preferably 65 ° C. or higher, and further preferably 70 ° C. or higher, from the viewpoint of improving the durability of the toner. Further, from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 140 ° C. or lower, more preferably 120 ° C. or lower, still more preferably 110 ° C. or lower, and further preferably 100 ° C. or lower.

  The acid value of the crystalline composite resin C is preferably 1 mgKOH / g or more, more preferably 2 mgKOH / g or more, and further preferably 3 mgKOH / g or more, from the viewpoint of improving the productivity of the toner. From the viewpoint of durability, it is preferably 20 mgKOH / g or less, more preferably 15 mgKOH / g or less, and still more preferably 10 mgKOH / g or less.

  The toner of the present invention may contain a crystalline resin other than the crystalline composite resin C, but the content of the crystalline composite resin C is 50% by mass or more from the viewpoint of durability in the crystalline resin. Is preferable, 80% by mass or more is more preferable, and 90% by mass or more is more preferable. Moreover, 100 mass% or less is preferable and 100 mass% is more preferable.

  The content of the crystalline composite resin C in the binder resin is preferably 5% by mass or more, more preferably 7% by mass or more, and further preferably 8% by mass or more from the viewpoint of improving the low-temperature fixability of the toner. Further, from the viewpoint of improving the durability of the toner, the content is preferably 40% by mass or less, more preferably 30% by mass or less, further preferably 20% by mass or less, and further preferably 15% by mass or less.

  The amorphous composite resin A contained in the amorphous resin includes a polycondensation resin component obtained by polycondensation of an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound, a styrene resin component, It is resin containing.

  Examples of the polycondensation resin component include polyester, polyester / polyamide, and the like. From the viewpoint of improving low-temperature fixability and durability of the toner, polyester is preferable.

  The polyester is preferably obtained by polycondensation of an alcohol component containing a divalent or higher alcohol and a carboxylic acid component containing a divalent or higher carboxylic acid compound.

  The alcohol component is represented by the formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is an ethylene and / or propylene group, x and y are the average number of moles of alkylene oxide added, each being a positive number, The sum value is preferably 1 or more, more preferably 1.5 or more, and preferably 16 or less, more preferably 8 or less, and further preferably 4 or less)
It is preferable to contain the alkylene oxide adduct of bisphenol A represented by these.

  As the alkylene oxide adduct of bisphenol A represented by the formula (I), RO is propylene oxide in the formula (I) such as polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane. Examples include propylene oxide adducts of bisphenol A, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, and other formulas (I) such as bisphenol A ethylene oxide adducts where RO is ethylene oxide. It is done.

  The content of the alkylene oxide adduct of bisphenol A represented by the formula (I) is 70 mol% or more in the alcohol component of the amorphous composite resin A from the viewpoint of improving the low-temperature fixability and durability of the toner. Preferably, 80 mol% or more is more preferable, and 90 mol% or more is more preferable. Moreover, 100 mol% or less is preferable, substantially 100 mol% is more preferable, and 100 mol% is further more preferable.

  Other alcohol components include aromatic diols other than alkylene oxide adducts of bisphenol A, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol. 1,6-hexanediol, 1,4-butenediol, 1,3-butanediol, aliphatic diols such as neopentyl glycol, and trivalent or higher alcohols such as glycerin.

  The carboxylic acid component contains an aromatic dicarboxylic acid compound from the viewpoint of toner durability and charge stability.

  Examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, terephthalic acid; anhydrides of these acids and alkyl (carbon number 1 to 3) esters of these acids, among which terephthalic acid is preferable. . In the present invention, the carboxylic acid compound includes not only a free acid but also an anhydride that decomposes during the reaction to produce an acid and an alkyl ester having 1 to 3 carbon atoms.

  The content of the aromatic dicarboxylic acid compound is preferably 10 mol% or more, more preferably 15 mol% or more, and even more preferably 20 mol% or more from the viewpoint of durability in the carboxylic acid component of the amorphous composite resin A. From the viewpoint of low-temperature fixability, 70 mol% or less is preferable, 60 mol% or less is more preferable, and 50 mol% or less is more preferable.

  The carboxylic acid component preferably further contains an aliphatic dicarboxylic acid compound from the viewpoint of low-temperature fixability.

  The chain hydrocarbon group in the aliphatic dicarboxylic acid compound may be linear or branched, and the aliphatic dicarboxylic acid compound preferably has 4 or more carbon atoms. Further, from the viewpoint of availability, it is preferably 14 or less, and more preferably 12 or less. In the present invention, the carboxylic acid compound includes not only a free acid but also an anhydride that decomposes during the reaction to produce an acid and an alkyl ester having 1 to 3 carbon atoms. However, the carbon number of the alkyl group in the alkyl ester portion is not included in the carbon number of the aliphatic dicarboxylic acid compound.

  Aliphatic dicarboxylic acid compounds include succinic acid (carbon number: 4), fumaric acid (carbon number: 4), glutaric acid (carbon number: 5), adipic acid (carbon number: 6), suberic acid (carbon number: 8) Azelaic acid (carbon number: 9), sebacic acid (carbon number: 10), dodecanedioic acid (carbon number: 12), tetradecanedioic acid (carbon number: 14), side chain with alkyl or alkenyl group And succinic acid, anhydrides of these acids, alkyl esters having 1 to 3 carbon atoms, and the like.

  The content of the aliphatic dicarboxylic acid compound is preferably 10 mol% or more, more preferably 15 mol% or more of the aliphatic dicarboxylic acid compound in the carboxylic acid component of the amorphous composite resin A from the viewpoint of low-temperature fixability. From the viewpoint of durability, it is preferably 70 mol% or less, more preferably 60 mol% or less, and further preferably 50 mol% or less.

  Other carboxylic acid components include: cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid; trivalent or higher carboxylic acids such as trimellitic acid and pyromellitic acid; and anhydrides of these acids, alkyls (1 to 3 carbon atoms) ) Ester; rosin; rosin modified with fumaric acid, maleic acid, acrylic acid and the like.

  In addition, a monovalent alcohol may be appropriately contained in the alcohol component, and a monovalent carboxylic acid compound may be appropriately contained in the carboxylic acid component from the viewpoint of adjusting the molecular weight.

  The equivalent ratio (COOH group / OH group) of the carboxylic acid component to the alcohol component in the polycondensation resin component is preferably 0.7 or more, more preferably 0.8 or more, from the viewpoint of adjusting the softening point of the composite resin. , Preferably 1.5 or less, more preferably 1.1 or less.

  The polycondensation reaction of the raw material monomer of the polycondensation resin component is carried out in an inert gas atmosphere at a temperature of about 180 ° C. to 250 ° C. in the presence of an esterification catalyst, a polymerization inhibitor, etc. as necessary. I can. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropylate bistriethanolamate. Examples of the catalyst include gallic acid. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1.5 parts by mass or less, more preferably 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Preferably it is 1.0 mass part or less. The amount of the esterification promoter used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass or less, with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less.

  As a raw material monomer for the styrene-based resin component, at least styrene or styrene derivatives such as α-methylstyrene and vinyltoluene (hereinafter, styrene and styrene derivatives are collectively referred to as “styrene compound”) is used.

  The content of the styrene compound is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, from the viewpoint of improving the durability of the toner in the raw material monomer of the styrene resin component. The mass% or more is more preferable. Further, from the viewpoint of low-temperature fixability, it is preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 88% by mass or less.

  Raw material monomers for styrene resin components used in addition to styrene compounds include (meth) acrylic acid alkyl esters; ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; and halovinyls such as vinyl chloride. Vinyl esters such as vinyl acetate and vinyl propionate; ethylenic monocarboxylic esters such as dimethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl pyrrolidone N-vinyl compounds such as

  The raw material monomer of the styrene resin component used in addition to the styrene compound can be used in combination of two or more. In the present specification, “(meth) acrylic acid” means acrylic acid and / or methacrylic acid.

  Among the raw material monomers for the styrene resin component used in addition to the styrene compound, (meth) acrylic acid alkyl esters are preferred from the viewpoint of improving the low-temperature fixability of the toner. From the above viewpoint, the carbon number of the alkyl group in the (meth) acrylic acid alkyl ester is preferably 1 or more, more preferably 8 or more, and preferably 22 or less, more preferably 18 or less. In addition, carbon number of this alkyl ester means carbon number derived from the alcohol component which comprises ester.

  Specific examples of (meth) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (iso or tertiary ) Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (iso) octyl (meth) acrylate, (iso) decyl (meth) acrylate, (iso) stearyl (meth) acrylate, and the like. Here, “(iso or tertiary)” and “(iso)” mean that both of these groups are present and not present, and when these groups are not present Indicates normal. Further, “(meth) acrylate” indicates that both acrylate and methacrylate are included.

  The content of the (meth) acrylic acid alkyl ester is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 12% by mass or more, from the viewpoint of low-temperature fixability in the raw material monomer of the styrene resin component. From the viewpoint of durability, it is preferably 50% by mass or less, more preferably 40% by mass or less, further preferably 30% by mass or less, and further preferably 25% by mass or less.

  A resin obtained by addition polymerization of a raw material monomer containing a styrene compound and a (meth) acrylic acid alkyl ester is also referred to as a styrene- (meth) acrylic resin.

  The addition polymerization reaction of the raw material monomer of the styrenic resin component can be carried out by a conventional method, for example, in the presence of a polymerization initiator such as dicumyl peroxide, a crosslinking agent, etc., in the presence of an organic solvent or in the absence of a solvent. The temperature condition is preferably 110 ° C. or higher, more preferably 140 ° C. or higher, and preferably 200 ° C. or lower, more preferably 170 ° C. or lower.

  When an organic solvent is used in the addition polymerization reaction, xylene, toluene, methyl ethyl ketone, acetone or the like can be used. The amount of the organic solvent used is preferably about 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the raw material monomer of the styrene resin component.

  From the viewpoint of improving the low-temperature fixability and durability of the toner, the amorphous composite resin A is a raw material for the polycondensation resin component, in addition to the raw material monomer for the polycondensation resin component and the raw material monomer for the styrene resin component. A resin (hybrid resin) obtained by using both reactive monomers capable of reacting with both the monomer and the raw material monomer of the styrene resin component is preferable. Accordingly, when the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component are polymerized to obtain the amorphous composite resin A, the polycondensation reaction and / or the addition polymerization reaction are carried out by the presence of both reactive monomers. It is preferable to carry out below. As a result, the amorphous composite resin A becomes a resin (hybrid resin) in which a polycondensation resin component and a styrene resin component are bonded via a structural unit derived from both reactive monomers, and the polycondensation resin component and styrene are combined. The resin component is more finely and uniformly dispersed.

  That is, the amorphous composite resin A includes (a) a raw material monomer of a polycondensation-based resin component containing an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and (b) a raw material of a styrene-based resin component. The resin is preferably a resin obtained by polymerizing monomers and (c) a bi-reactive monomer capable of reacting with both the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component.

  As the both reactive monomers, at least one functional group selected from the group consisting of a hydroxyl group, a carboxy group, an epoxy group, a primary amino group and a secondary amino group in the molecule, preferably a hydroxyl group and / or A compound having a carboxy group, more preferably a carboxy group, and an ethylenically unsaturated bond is preferred. By using such a bireactive monomer, the dispersibility of the resin to be a dispersed phase can be further improved. The both reactive monomers are preferably at least one selected from the group consisting of acrylic acid, methacrylic acid, fumaric acid, maleic acid and maleic anhydride, but from the viewpoint of reactivity of polycondensation reaction and addition polymerization reaction Therefore, acrylic acid, methacrylic acid or fumaric acid is more preferable. However, when used with a polymerization inhibitor, a polyvalent carboxylic acid compound having an ethylenically unsaturated bond such as fumaric acid functions as a raw material monomer for the polycondensation resin component. In this case, fumaric acid or the like is not a bireactive monomer but a raw material monomer for a polycondensation resin component.

The amount of the both reactive monomers used is preferably 0.5 mol or more, more preferably 1 mol or more, based on 100 mol of the total of the alcohol components of the polycondensation resin component, from the viewpoint of low-temperature fixability. From the viewpoint of enhancing the dispersibility of the component and the polycondensation resin component and improving the durability of the toner, the amount is preferably 30 mol or less, more preferably 20 mol or less, and even more preferably 10 mol or less.
In addition, the amount of both reactive monomers used is preferably 1 part by mass or more, more preferably 2 parts by mass or more, with respect to a total of 100 parts by mass of the raw material monomers for the styrene resin component, from the viewpoint of low-temperature fixability. From the viewpoint of enhancing the dispersibility of the styrene resin component and the polycondensation resin component and improving the durability of the toner, preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less. It is. Here, the polymerization initiator is included in the total of the raw material monomers of the styrene resin component.

  The method for producing a hybrid resin using both reactive monomers is the same as that for the crystalline composite resin C.

  In the amorphous composite resin A, the mass ratio of the polycondensation resin component to the styrene resin component (polycondensation resin component / styrene resin component) is preferably 55/45 or more from the viewpoint of low-temperature fixability. / 30 or more is more preferable, and 80/20 or more is more preferable. Further, from the viewpoint of durability, 95/5 or less is preferable, and 90/10 or less is more preferable. In the above calculation, the mass of the polycondensation resin component is an amount obtained by subtracting the amount of reaction water (calculated value) dehydrated by the polycondensation reaction from the mass of the raw material monomer of the polycondensation resin used. The amount of both reactive monomers is included in the amount of raw material monomers of the polycondensation resin component. The amount of the styrene resin component is the amount of the raw material monomer of the styrene resin component, and includes the amount of the polymerization initiator.

  From the viewpoint of improving the durability of the toner, the softening point of the amorphous composite resin A is preferably 90 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 105 ° C. or higher. Further, from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 150 ° C. or lower, more preferably 140 ° C. or lower. When two or more kinds of amorphous composite resins A are contained, the weighted average value of the softening points is preferably in the above range.

  The maximum endothermic peak temperature of the amorphous composite resin A is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 60 ° C. or higher from the viewpoint of improving the durability of the toner. Further, from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 100 ° C. or lower, more preferably 90 ° C. or lower, and further preferably 80 ° C. or lower.

  From the viewpoint of improving the durability of the toner, the glass transition temperature of the amorphous composite resin A is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 60 ° C. or higher. Further, from the viewpoint of improving the low-temperature fixability of the toner, it is preferably 80 ° C. or lower, more preferably 75 ° C. or lower, and further preferably 70 ° C. or lower. The glass transition temperature is a physical property peculiar to the amorphous phase and is distinguished from the highest peak temperature of endotherm.

  The acid value of the amorphous composite resin A is preferably 40 mgKOH / g or less, more preferably 30 mgKOH / g or less, and further preferably 25 mgKOH / g or less, from the viewpoint of improving the environmental stability of the charge amount of the toner. Further, it is preferably 1 mgKOH / g or more, more preferably 2 mgKOH / g or more.

  The toner of the present invention may contain an amorphous resin other than the amorphous composite resin A, such as a composite resin, a vinyl resin, an epoxy resin, a polycarbonate resin, and a polyurethane resin. The content of the amorphous composite resin A is preferably 50% by mass or more, more preferably 80% by mass or more, and 90% by mass or more from the viewpoint of improving the low-temperature fixability and durability of the toner in the amorphous resin. Is more preferable. Moreover, 100 mass% or less is preferable and 100 mass% is more preferable.

  The mass ratio of the crystalline resin to the amorphous resin (crystalline resin / amorphous resin) is preferably 5/95 or more, more preferably 7/93 or more from the viewpoint of low-temperature fixability, and from the viewpoint of durability. 30/70 or less is preferable, 20/80 or less is more preferable, and 15/85 or less is more preferable.

  In the present invention, the release agent preferably contains a hydrocarbon wax from the viewpoint of suppressing the occurrence of paper wrapping during fixing.

  Hydrocarbon waxes include low molecular weight polypropylene, low molecular weight polyethylene, low molecular weight polypropylene polyethylene copolymers; hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, sazol wax, and oxides thereof. Of these, paraffin wax is preferred from the viewpoint of suppressing the occurrence of paper wrapping during fixing.

  The melting point of the release agent is preferably 60 ° C. or higher, more preferably 65 ° C. or higher, further preferably 70 ° C. or higher, and low-temperature fixability of the toner, from the viewpoint of suppressing suppression of paper wrapping during toner fixing and durability. From the viewpoint of improving the temperature, it is preferably 140 ° C. or lower, more preferably 120 ° C. or lower, and further preferably 90 ° C. or lower.

  Examples of mold release agents other than hydrocarbon waxes include carnauba wax, montan wax and their deoxidized wax, ester waxes such as fatty acid ester wax, fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts, and the like. However, the content of the hydrocarbon wax is preferably 60% by mass or more, more preferably 80% by mass or more, and 95% by mass in the release agent from the viewpoint of suppressing the occurrence of paper wrapping during fixing and continuous printing. The above is more preferable, 100% by mass or less is preferable, substantially 100% by mass is more preferable, and 100% by mass is further preferable.

  The content of the release agent is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and 2.5 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of suppressing paper winding at the time of fixing and continuous printing. Is more preferably 3 parts by mass or more, more preferably 3 parts by mass or more, and from the viewpoint of durability, 8 parts by mass or less is preferable, and 6 parts by mass or less is more preferable.

  The electrophotographic toner of the present invention may contain a colorant, a charge control agent and the like in addition to the binder resin and the release agent.

  As the colorant, all of dyes and pigments used as toner colorants can be used, such as carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow and the like can be used, and the toner of the present invention may be either a black toner or a color toner. As the colorant, phthalocyanine blue 15: 3 (PB15: 3), phthalocyanine blue 15: 4 (PB15: PB15: from the viewpoint of improving the durability of the toner, and improving the low-temperature fixability and heat-resistant storage stability of the toner. 4) and carbon black are preferable, and phthalocyanine blue 15: 3 is more preferable.

  The content of the colorant is preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, from the viewpoint of improving the toner image density with respect to 100 parts by mass of the binder resin. Further, from the viewpoint of improving the durability of the toner, and from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner, it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 7 parts by mass or less. .

  The charge control agent is not particularly limited, and may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent.

  Examples of positively chargeable charge control agents include nigrosine dyes such as “Nigrosine Base EX”, “Oil Black BS”, “Oil Black SO”, “Bontron N-01”, “Bontron N-04”, “Bontron N-07 ”,“ Bontron N-09 ”,“ Bontron N-11 ”(manufactured by Orient Chemical Co., Ltd.) and the like; triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as“ Bontron P-51 "(manufactured by Orient Chemical Co., Ltd.), cetyltrimethylammonium bromide," COPY CHARGE PX VP435 "(manufactured by Clariant), etc .; polyamine resin such as" AFP-B "(manufactured by Orient Chemical Industries, Ltd.) Imidazole derivatives such as “PLZ-2001” and “PLZ-8001” (manufactured by Shikoku Kasei Kogyo Co., Ltd.); styrene-acrylic resins such as “FCA-701PT” (Fujikura Chemical) Etc., Ltd.) Co., Ltd., and the like.

  In addition, as the negatively chargeable charge control agent, metal-containing azo dyes such as “Varifast Black 3804”, “Bontron S-31”, “Bontron S-32”, “Bontron S-34”, “Bontron S-36” (Above, manufactured by Orient Chemical Co., Ltd.), “Eisenspiron Black TRH”, “T-77” (manufactured by Hodogaya Chemical Co., Ltd.), etc .; metal compounds of benzylic acid compounds such as “LR-147” , “LR-297” (manufactured by Nippon Carlit Co., Ltd.), etc .; metal compounds of salicylic acid compounds such as “Bontron E-81”, “Bontron E-84”, “Bontron E-88”, “Bontron E-” 304 "(manufactured by Orient Chemical Co., Ltd.)," TN-105 "(manufactured by Hodogaya Chemical Co., Ltd.), etc .; copper phthalocyanine dyes; quaternary ammonium salts such as" COPY CHARGE NX VP434 "(manufactured by Clariant) Nitroimidazole derivatives Etc .; organometallic compounds and the like.

  The content of the charge control agent is preferably 0.01 parts by mass or more and more preferably 0.2 parts by mass or more with respect to 100 parts by mass of the binder resin from the viewpoint of the charging stability of the toner. Further, from the same viewpoint, it is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, further preferably 3 parts by mass or less, and further preferably 2 parts by mass or less.

  In the toner of the present invention, additives such as magnetic powder, fluidity improver, conductivity adjuster, reinforcing filler such as fibrous substance, antioxidant, anti-aging agent, and cleanability improver are appropriately used. It may be.

The electrophotographic toner of the present invention may be a toner obtained by any conventionally known method such as a melt-kneading method, an emulsion phase inversion method, or a polymerization method. However, from the viewpoint of improving the durability of the toner, the toner From the viewpoint of improving the low temperature fixability of the toner, a pulverized toner by a melt kneading method is preferable. In particular,
Step 1: Step of melting and kneading a toner component containing a crystalline composite resin C, an amorphous composite resin A and a release agent using an open roll type kneader, and Step 2: pulverizing the obtained kneaded product The pulverized toner obtained by a method including a classification step is preferable from the viewpoint of excellent low-temperature fixability and durability, and the suppression of the occurrence of paper wrapping during fixing and continuous printing, which is the effect of the present invention, is more remarkable. Demonstrated.

  In step 1, melt kneading of the toner component including the crystalline composite resin C, the amorphous composite resin A and the release agent, and if necessary, a colorant, a charge control agent, etc. is repeated kneading or using a dispersion aid. It is preferable to use an open roll type kneader from the viewpoint that toner components such as a release agent, a colorant, a charge control agent and the like can be efficiently and highly dispersed in the binder resin without the need for soldering.

  The toner components such as the crystalline composite resin C, the amorphous composite resin A, the release agent, the colorant, and the charge control agent are mixed in advance by a mixer such as a Henschel mixer and a ball mill, and then supplied to the kneader. preferable.

  The open roll type kneader means an open kneading unit that is not sealed, and can easily dissipate the kneading heat generated during kneading. Further, the continuous open roll type kneader is preferably a kneader equipped with at least two rolls, and the continuous open roll type kneader used in the present invention comprises two rolls having different peripheral speeds, That is, the kneading machine includes two rolls, a high rotation side roll having a high peripheral speed and a low rotation side roll having a low peripheral speed. In the present invention, the viewpoint of improving the dispersibility in the toner of additives such as a release agent, a colorant, and a charge control agent, a viewpoint of reducing mechanical force at the time of melt kneading and suppressing heat generation, and melt kneading From the viewpoint of reducing the temperature at the time and improving the durability and low-temperature fixability of the toner, the high rotation side roll is preferably a heating roll and the low rotation side roll is preferably a cooling roll.

  The temperature of the roll can be adjusted by, for example, the temperature of the heat medium passed through the inside of the roll, and each roll may be divided into two or more locations through the heat medium having different temperatures.

  The raw material charging side end temperature of the high-rotation side roll is preferably 100 ° C. or higher and 160 ° C. from the viewpoint of reducing mechanical force during melt-kneading and suppressing heat generation, and improving the durability and low-temperature fixability of the toner. From the same viewpoint, the raw material charging side end temperature of the low rotation side roll is preferably 30 ° C. or higher and 100 ° C. or lower.

  In the high rotation side roll, the difference in the set temperature between the raw material input side end and the kneaded product discharge side end prevents the kneaded product from detaching from the roll, reduces the mechanical force during melt kneading, and suppresses heat generation From the viewpoint of improving the durability and low-temperature fixability of the toner, the temperature is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, and preferably 60 ° C. or lower, more preferably 50 ° C. or lower.

  In the low rotation side roll, the difference in the set temperature between the raw material input side end and the kneaded product discharge side end improves the dispersibility in the toner of additives such as release agents, colorants, and charge control agents. From the viewpoint of reducing mechanical force during melt-kneading and suppressing heat generation, and improving the durability and low-temperature fixability of the toner, it is preferably 0 ° C. or higher, more preferably 10 ° C. or higher, more preferably 20 ° C. or higher. Moreover, it is preferable that it is 50 degrees C or less.

  Peripheral speed of the high rotation side roll is to improve the dispersibility in the toner of additives such as a release agent, a colorant, and a charge control agent, to reduce mechanical force during melt kneading, and to suppress heat generation From the viewpoint of improving the durability and low-temperature fixability of the toner, it is preferably 2 m / min or more, more preferably 10 m / min or more, still more preferably 25 m / min or more, and preferably 100 m / min or less. More preferably, it is 75 m / min or less, More preferably, it is 50 m / min or less.

  From the same viewpoint, the peripheral speed of the low-rotation side roll is preferably 1 m / min or more, more preferably 5 m / min or more, still more preferably 15 m / min or more, and preferably 90 m / min or less, more preferably Is 60 m / min or less, more preferably 30 m / min or less. Further, the ratio of the peripheral speeds of the two rolls (low rotation side roll / high rotation side roll) is preferably 0.10 or more, more preferably 0.30 or more, and still more preferably 0.50 or more, from the viewpoint of low-temperature fixability and durability. From the viewpoint of low-temperature fixability and durability, it is preferably 0.80 or less, more preferably 0.75 or less, and still more preferably 0.7 or less.

  The structure, size, material, etc. of the roll are not particularly limited, and the roll surface may be any of smooth, corrugated, uneven, etc., but the kneading share is increased, release agent, colorant, charge control. From the viewpoints of improving the dispersibility of additives such as additives in the toner, reducing the mechanical force during melt-kneading, suppressing heat generation, and improving the durability and low-temperature fixability of the toner, It is preferable that a plurality of spiral grooves are carved on the surface.

  The kneaded product obtained in step 1 is appropriately cooled until reaching a pulverizable hardness, and in step 2, pulverized.

  The kneaded product may be pulverized in multiple stages. For example, the kneaded product may be coarsely pulverized to about 1 to 5 mm, and then finely pulverized to a desired particle size.

  The pulverizer used for the pulverization is not particularly limited, and examples of the pulverizer suitably used for the coarse pulverization include a hammer mill, an atomizer, and a rotoplex. Further, examples of the pulverizer suitably used for fine pulverization include a fluidized bed type counter jet mill, a collision plate type jet mill, and a rotary mechanical mill.

  Examples of classifiers used for classification include airflow classifiers, inertia classifiers, and sieve classifiers. At the time of classification, the pulverized product that has been removed due to insufficient pulverization may be subjected to the pulverization step again, and pulverization and classification may be repeated as necessary.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably 3 μm or more, more preferably 4 μm or more, further preferably 5 μm or more, and the amount of fine powder having a particle size of 3 μm or less is reduced from the viewpoint of productivity. From the viewpoint, it is preferably 15 μm or less, more preferably 10 μm or less, and further preferably 8 μm or less. In the present specification, the volume-median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size. When the toner is treated with an external additive, the volume median particle size of the toner particles before being treated with the external additive is defined as the volume median particle size of the toner.

  In the toner of the present invention, the content of particles having a particle size of 3 μm or less is 5.0% by number or less from the viewpoint of suppressing paper winding at the time of initial fixing in the toner, and paper winding at the time of fixing during continuous printing. 4.0% by number or less is preferable from the viewpoint of suppressing the above, more preferably 3.0% by number or less, and from the viewpoint of productivity and low-temperature fixability, 1.0% by number or more is preferable, and 2.0% by number or more is more preferable. The content of particles having a particle size of 3 μm or less can be adjusted by classification.

  The average circularity of the toner is 0.940 or more, preferably 0.950 or more, preferably 0.960 or more, from the viewpoint of suppressing the occurrence of paper wrapping at the time of fixing during continuous printing and from the viewpoint of durability. More preferably, from the viewpoint of productivity and cleaning properties, 0.980 or less is preferable, and 0.970 or less is more preferable. The degree of circularity of the toner can be adjusted by a method such as the retention time of the toner in the pulverizer and the number of pulverization processes in the pulverizer. The longer the residence time and the greater the number of pulverization processes, the higher the average circularity. Become.

  In the toner of the present invention, it is preferable to use an external additive in order to improve transferability. Examples of the external additive include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide and zinc oxide, and organic fine particles such as resin particles such as melamine resin fine particles and polytetrafluoroethylene resin fine particles. The above may be used in combination. Among these, silica is preferable, and hydrophobic silica that has been subjected to a hydrophobic treatment is more preferable from the viewpoint of toner transferability.

  Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. It is done.

  The average particle diameter of the external additive is preferably 10 nm or more, and more preferably 15 nm or more, from the viewpoint of the chargeability, fluidity, and transferability of the toner. From the same viewpoint, 250 nm or less is preferable, 200 nm or less is more preferable, and 90 nm or less is more preferable.

  The content of the external additive is preferably 0.05 parts by mass or more, and 0.1 parts by mass or more with respect to 100 parts by mass of the toner before being processed with the external additive, from the viewpoint of chargeability, fluidity, and transferability of the toner. More preferred is 0.3 part by mass or more. Further, from the same viewpoint, it is preferably 5 parts by mass or less, and more preferably 3 parts by mass or less.

  The toner of the present invention can be used as a one-component developing toner or as a two-component developer mixed with a carrier.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The physical properties of the resin and the like were measured by the following method.

[Softening point of resin]
Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), 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, 1 mm in diameter and 1 mm in length. Extrude from the nozzle. The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening point.

[Maximum peak temperature of resin endotherm]
Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, and the temperature falls from room temperature to 10 ° C./min at 0 ° C. Cool to 0 ° C and hold at 0 ° C for 1 minute. Thereafter, the measurement is performed at a heating rate of 50 ° C./min. Among the observed endothermic peaks, the temperature of the peak on the highest temperature side is defined as the highest endothermic peak temperature.

[Glass transition temperature of resin]
Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan), 0.01 to 0.02 g of sample is weighed into an aluminum pan, heated up to 200 ° C., and the temperature drop rate from that temperature Cool to -10 ° C at 10 ° C / min. Next, the sample is heated and measured at a heating rate of 10 ° C./min. The glass transition temperature is defined as the temperature at 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.

[Acid value of the resin]
Measured according to the method of JIS K0070. However, only the measurement solvent is changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Melting point of release agent]
Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan and heated to 200 ° C. at a heating rate of 10 ° C./min. The temperature is raised and the temperature is cooled to 0 ° C at a rate of temperature drop of 10 ° C / min. Next, the sample is heated to 180 ° C. at a heating rate of 10 ° C./min and measured. The maximum peak temperature of the endotherm observed from the melting endotherm curve thus obtained is taken as the melting point of the release agent.

[Average particle diameter of external additive]
The average particle diameter refers to the number average particle diameter. The particle diameter (average value of major axis and minor axis) of 500 particles is measured from a scanning electron microscope (SEM) photograph, and the number average value thereof is used.

[Volume-median particle size (D ₅₀ ) and content of particles having a particle size of 3 μm or less]
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 100μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter, Inc.)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (polyoxyethylene lauryl ether, HLB (Griffin): 13.6), dissolved in electrolyte solution, adjusted to 5% by weight Dispersion condition: 10 mg of measurement sample in 5 ml of the dispersion And then dispersed for 1 minute with an ultrasonic disperser (machine name: US-1 manufactured by SND Co., Ltd., output: 80 W), and then 25 ml of the electrolyte is added. For 1 minute to prepare a sample dispersion.
Measurement conditions: The sample dispersion is added to 100 ml of the electrolytic solution so that the particle size of 30,000 particles can be measured in 20 seconds, and 30,000 particles are measured. The median particle size (D ₅₀ ) and the content (number%) of particles having a particle size of 3 μm or less are determined.

[Average circularity of toner]
Measuring machine: FPIA-3000 (manufactured by Sysmex Corporation)
Standard unit (10x objective lens)
Measurement mode HPF mode version 00-10
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB13.6) 5% by weight Electrolyte dispersion condition: 10 mg of measurement sample was added to 10 ml of dispersion, and dispersed for 1 minute with an ultrasonic disperser. Thereafter, 10 ml of distilled water is added, and further dispersed for 2 minutes with an ultrasonic disperser.
Measurement conditions: The degree of circularity of the toner dispersed in the dispersion is measured at 20 ° C. at a concentration of 1800 to 2200 particles, and a number average value is obtained.

Resin Production Example 1 [Resin C1, C2]
Raw material monomers of the polycondensation resin component other than sebacic acid shown in Table 1 were placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 120 ° C. At 120 ° C., 1.5 kg of sebacic acid shown in Table 1 was added, further heated to 160 ° C., and reacted for 6 hours. Then, the raw material monomer of the styrene resin component shown in Table 1 and the both reactive monomers were added dropwise over 1 hour using a dropping funnel. After aging the addition polymerization reaction for 1 hour while maintaining at 160 ° C., the raw material monomer of the styrene resin component was removed at 8.3 kPa for 1 hour. Further, the remaining sebacic acid was added, the temperature was raised to 200 ° C. over 8 hours, and the mixture was reacted at 8.3 kPa for 30 minutes. Further, 20 g of tin (II) 2-ethylhexanoate and 2 g of gallic acid were added, reacted at 200 ° C. for 1 hour, and then reacted at 8.3 kPa for 1 hour to obtain a crystalline hybrid resin.

Resin Production Example 2 [Resin C3]
The raw material monomers shown in Table 1 were placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 140 ° C. The mixture was further heated to 200 ° C. and reacted for 10 hours, and then reacted at 8.3 kPa for 30 minutes.
Further, 20 g of tin (II) 2-ethylhexanoate and 2 g of gallic acid were added, reacted at 200 ° C. for 1 hour, and then reacted at 8.3 kPa for 1 hour to obtain a crystalline polyester.

Resin Production Example 3 [Resin A1]
Raw material monomers of polycondensation resin components other than fumaric acid and trimellitic anhydride shown in Table 2, 40 g of tin (II) 2-ethylhexanoate and 1 g of gallic acid were added to a nitrogen introduction tube, dehydration tube, stirrer and thermocouple. The flask was placed in a 10-liter four-necked flask equipped, reacted at 230 ° C. for 8 hours, and then reacted at 8.3 kPa for 1 hour.
The temperature was lowered to 170 ° C., and raw material monomers of the styrenic resin component, both reactive monomers, and dicumyl peroxide were added dropwise over 1 hour using a dropping funnel. After aging the addition polymerization reaction for 1 hour while maintaining at 170 ° C, the temperature was raised to 210 ° C and the raw monomer of the styrene resin component was removed at 8.3 kPa for 1 hour, and both reactive monomers and polycondensation resin were used. Reaction of the (polyester) part was performed. Furthermore, 5 g of trimellitic anhydride, fumaric acid and tertiary butyl catechol were added at 210 ° C., and the reaction was carried out until the desired softening point was reached to obtain an amorphous hybrid resin.

Resin Production Example 4 [Resin A2]
Raw material monomers other than fumaric acid and trimellitic anhydride shown in Table 2, 40 g of tin (II) 2-ethylhexanoate and 1 g of gallic acid were added in a 10 liter volume equipped with a nitrogen introduction tube, dehydration tube, stirrer and thermocouple. The mixture was placed in a four-necked flask and reacted at 230 ° C. for 8 hours. After the reaction, the mixture was reacted at 8.3 kPa for 1 hour.
Further, the temperature was lowered to 210 ° C., 5 g of trimellitic anhydride, fumaric acid and tertiary butyl catechol were added, and the reaction was carried out until the softening point reached 138.1 ° C. to obtain an amorphous polyester.

Examples 1-6, 9, 10 and Comparative Examples 1-9
The specified amount of binder resin shown in Table 3, 4 parts by weight of coloring agent “ECB-301” (manufactured by Dainichi Seika Co., Ltd., phthalocyanine blue (PB15: 3)), charge control agent “Bontron E-304” (Oriento Chemical) (Made by Kogyo Co., Ltd.) 0.5 parts by weight and 5 parts by weight of release agent “HNP-9” (manufactured by Nippon Seiwa Co., Ltd., paraffin wax, melting point: 75 ° C.) were mixed in a Henschel mixer and then melt-kneaded under the conditions shown below did.

  The obtained raw material mixture was supplied to a continuous open roll kneader “NIDEX” (manufactured by Mitsui Mining Co., Ltd.) with a table feeder and kneaded to obtain a kneaded product. The continuous open roll type kneader used at this time had a roll outer diameter of 0.14 m and an effective roll length of 0.8 m, and the operating conditions were that the rotation speed of the high rotation side roll (front roll) was 75 r / min (peripheral speed 33m / min), low speed side roll (rear roll) rotation speed 50r / min (peripheral speed 22m / min), ratio of peripheral speed of two rolls (low speed side roll / high speed side) Roll) was 0.67, and the roll gap was 0.1 mm. The heating and cooling medium temperature in the roll is 150 ° C on the raw material input side of the high-rotation roll, 100 ° C on the kneaded material discharge side, 75 ° C on the raw material input side of the low-rotation roll, and the kneaded material discharge side The temperature of was set to 30 ° C. The feed rate of the raw material mixture was 10 kg / h, and the average residence time was about 5 minutes.

  The obtained kneaded product was cooled and coarsely pulverized by a pulverizer “Rotoplex” (manufactured by Toa Machinery Co., Ltd.) to obtain a coarsely pulverized product having a particle size of 2 mm or less using a sieve having an opening of 2 mm. Fine grinding and upper limit classification (removal of coarse powder) were performed with a turbo mill “RS400” (Freund Turbo). Furthermore, lower limit classification (fine powder removal) was performed with a classifier “TTSP” (manufactured by Hosokawa Alpine Co., Ltd.) to obtain toner particles having a volume median particle size of 7.0 μm. The toner circularity was adjusted by changing the raw material supply amount at the time of fine pulverization by the turbo mill and the number of times of fine pulverization by the turbo mill.

  100 parts by mass of the obtained toner particles, 1.0 part by mass of hydrophobic silica “R972” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle size: 16 nm), and hydrophobic silica “RY -50 ”(manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: silicone oil, average particle size: 40 nm) 1.0 part by mass with a Henschel mixer (manufactured by Mitsui Mining) at 3000 r / min (circumferential speed 32 m / sec) for 3 minutes The toner was obtained by mixing.

Examples 7 and 8
Instead of “HNP-9”, 5 parts by weight of “SP-105” (manufactured by Sasol, Fischer-Tropsch wax, melting point: 105 ° C.) is used as a release agent in Example 7, and “Carnauba wax C2” is used in Example 8. A toner was obtained in the same manner as in Example 1 except that 5 parts by mass (carnauba wax, melting point: 85 ° C., manufactured by Kato Yoko Co., Ltd.) was used.

Example 11
The operating conditions of the continuous open roll type kneader were changed to 60r / min (26m / min) for the rotation speed of the low rotation side roll (rear roll), and the ratio of the peripheral speeds of the two rolls (low rotation side roll) Toner was obtained in the same manner as in Example 1 except that (high rotation side roll) was changed to 0.78.

Test Example 1 [low temperature fixability]
Implement toner to the non-magnetic one-component developing device "Microline5400" (manufactured by Oki Data Corporation), solid images (toner amount: 1.1 mg / cm ²⁾ of 2 cm × 3 cm image unfixed 90g paper having a ( Obtained on Mondi Color Copy 90). Using an external fixing machine (fixing speed: 300 mm / sec) of “Microline 3050” (Oki Data Co., Ltd.), the fixing temperature was set to 130 ° C., and the unfixed image was fixed.
“Scotch (registered trademark) Mending Tape 810” (manufactured by Sumitomo 3M, width: 18 mm) was pasted on the fixed image, rubbed from above with a weight of 1.25 kg, and then the tape was peeled off. The image density before and after the tape was peeled off was measured using an image density measuring instrument “GRETAG SPM50” (manufactured by GRETAG), and the ratio between the two (after peeling / before sticking × 100) was taken as the fixing strength, 130 ° C. The low-temperature fixability was evaluated by the fixing strength. The results are shown in Table 3. The higher the fixing strength, the better the low-temperature fixing property. The fixing strength is preferably 95% or more, more preferably 97% or more, and even more preferably 98% or more.

Test Example 2 [Durability]
Load the toner cartridge of the non-magnetic one-component developing device "Microline 5400" (Oki Data Co., Ltd.) into an idling machine that can be driven by an external motor, and adjust the printing speed to 30 sheets / min. Was implemented. The idling machine was continuously operated, and the occurrence of streaks on the surface of the developing roller was visually observed every time corresponding to printing of 1000 sheets to evaluate the durability. Table 3 shows the number of lines when streaks occur. The more the number of streaks, the better the durability. The number is preferably 7000 (7K) or more, more preferably 8000 (8K) or more, and more preferably 9000 (9K) or more. . “> 10K” in the table indicates that no streak occurred up to 10,000 sheets (10K).

Test Example 3 [Initial paper winding]
A non-magnetic one-component developing device "Microline 5400" (Oki Data Co., Ltd.) is mounted with toner, and an unfixed image having a solid image of 2 cm x 3 cm (toner adhesion amount: 1.1 mg / cm ² ) is printed on 60 g paper ( SP paper manufactured by Fuji Xerox). Using the external fixing machine (fixing speed: 300 mm / sec) of the non-magnetic one-component developing device “Microline 3050” (Oki Data Co., Ltd.), while gradually increasing the fixing temperature from 140 ° C. to 180 ° C. The unfixed image was fixed and the presence or absence of paper wrapping was confirmed. Table 3 shows the temperature at which the paper winding occurred. The higher the paper winding temperature is, the more the paper winding is suppressed. The temperature is preferably 165 ° C. or higher, more preferably 170 ° C. or higher, and further preferably 175 ° C. or higher. Note that “> 180 ° C.” in the table indicates that no winding of the paper occurred even at 180 ° C.

Test example 4 [paper winding during continuous printing]
Load the toner cartridge of the non-magnetic one-component developing device "Microline 5400" (Oki Data Co., Ltd.) into an idling machine that can be driven by an external motor, and adjust the printing speed to 30 sheets / min. Was implemented. The idling machine was continuously operated and operated for a time corresponding to 3000 sheets printing.
The toner cartridge after 3,000 sheets printed corresponding operation is mounted on a non-magnetic one-component developing device "Microline5400" (manufactured by Oki Data Corporation), solid image of 2 cm × 3 cm (toner amount: 1.1 mg / cm ²⁾ and An unfixed image was obtained on 60 g paper (SP paper made by Fuji Xerox). Using the external fixing machine (fixing speed: 300mm / sec) of the non-magnetic one-component developing device "Microline3050" (Oki Data Co., Ltd.), while gradually increasing the fixing temperature from 140 ° C to 180 ° C, The unfixed image was fixed and the presence or absence of paper wrapping was confirmed. Table 3 shows the temperature at which the paper winding occurred. The paper winding temperature is preferably 165 ° C. or higher, more preferably 170 ° C. or higher, and even more preferably 175 ° C. or higher. Note that “> 180 ° C.” in the table indicates that no winding of the paper occurred even at 180 ° C.

From the comparison between Examples 1 and 2 and Comparative Example 1, it can be seen that when the content of the fine toner powder having a particle size of 3 μm or less is 5 mass% or less, paper wrapping at the initial fixing is suppressed. It can also be seen that the smaller the toner fine powder, the more the paper wrapping during fixing during continuous printing is suppressed.
By comparing Examples 1, 3, 4, and Comparative Example 2 and by comparing Examples 2, 5, 6, and Comparative Example 3, the higher the degree of circularity, the less the occurrence of paper wrapping during fixing during continuous printing. It is understood that it is excellent in durability.
From the comparison of Examples 1, 7, and 8, it can be seen that the use of paraffin wax as a mold release agent can more effectively suppress the occurrence of paper wrapping at the time of fixing during initial and continuous printing.
From the comparison of Examples 1 and 9, it can be seen that the higher the content of the amorphous composite resin in the amorphous resin, the better the durability.
From the comparison of Examples 1 and 10, it can be seen that the aliphatic diol as the raw material of the crystalline composite resin is preferably dodecanediol having 12 carbon atoms from the viewpoint of low-temperature fixability.
Compared with Examples 1 and 11, Example 1 in which the ratio of the peripheral speed between the high rotation side and the low rotation side is 0.67 is low temperature while suppressing occurrence of paper wrapping at the time of fixing at the initial time and continuous printing. It turns out that it is excellent in fixing property and durability.
From the comparison between Example 1 and Comparative Example 6, it can be seen that the use of an amorphous composite resin is superior in durability and low-temperature fixability as compared with amorphous polyester.
From the comparison between Example 1 and Comparative Example 7 and Example 9 and Comparative Example 8, it can be seen that the use of the crystalline composite resin is superior in durability and low-temperature fixability as compared with the crystalline polyester.

The electrophotographic toner of the present invention is suitably used for developing a latent image formed in an electrostatic image developing method, an electrostatic recording method, an electrostatic printing method, or the like.

Claims (8)

An electrophotographic toner containing a crystalline resin, an amorphous resin, and a release agent,
The crystalline resin is obtained by polycondensation of an alcohol component containing an aliphatic diol having 9 to 14 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms. Containing a crystalline composite resin C containing a condensation resin component and a styrene resin component;
Amorphous composite resin A, wherein the amorphous resin comprises a polycondensation resin component obtained by polycondensation of an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and a styrene resin component Containing
An electrophotographic toner in which the average circularity of the toner is 0.940 or more and the content of particles having a particle size of 3 μm or less in the toner is 5.0% by number or less.   The toner for electrophotography according to claim 1, wherein the release agent contains paraffin wax. The alcohol component of the polycondensation resin component of the amorphous composite resin A is represented by the formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is an ethylene and / or propylene group, x and y are the average number of moles of alkylene oxide added, each being a positive number, (The sum is between 1 and 16)
The toner for electrophotography according to claim 1, which contains 70 mol% or more of an alkylene oxide adduct of bisphenol A represented by the formula:   The toner for electrophotography according to claim 1, wherein the content of the amorphous composite resin A in the amorphous resin is 50% by mass or more.   Crystalline composite resin C includes (a) a polycondensation comprising an alcohol component containing an aliphatic diol having 9 to 14 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms. Polymerization of raw material monomers for resin-based resin components, (b) raw material monomers for styrene-based resin components, and (c) raw-material monomers for polycondensation-based resin components and raw-material monomers for styrene-based resin components The toner for electrophotography according to any one of claims 1 to 4, which is a resin obtained by applying the toner.   6. The electrophotographic toner according to claim 1, wherein the mass ratio of the crystalline resin to the amorphous resin (crystalline resin / amorphous resin) is 5/95 or more and 30/70 or less. Step 1: Step of melting and kneading a toner component containing a crystalline composite resin C, an amorphous composite resin A and a release agent using an open roll type kneader, and Step 2: pulverizing the obtained kneaded product The method for producing an electrophotographic toner according to claim 1, comprising a classification step.   The open roll type kneader is equipped with two rolls with different peripheral speeds, and the ratio of the peripheral speeds of the low rotation side rolls with low peripheral speed and the high rotation side rolls with high peripheral speed (low rotation side roll / high rotation side roll) ) Is 0.10 to 0.80.