JP6370206B2 - 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 or the like.

  In recent years, there has been a strong demand for improvement in low-temperature fixability of toners from the viewpoint of energy saving, that is, reduction of energy consumption in the fixing process as well as promotion of downsizing, high speed and high image quality of electrophotographic apparatuses.

With the object of providing a toner for developing electrostatic charge that has improved non-offset properties and impact resistance, is stable in triboelectric charge, and can be produced at low cost, an average particle size of 0.1 is added to toner particles composed of a binder resin and a colorant. It contains at least one or more of calcium carbonate, magnesium oxide, magnesium hydroxide, silicon dioxide, aluminum silicate, aluminum hydroxide, and zirconium silicate, which are in a granular form of ~ 5.0 μm and a BET specific surface area of 20 m ² / g or less. A characteristic electrostatic toner is disclosed (see Patent Document 1).

  In addition, it is a developer for an electrophotographic system in which a stable image density is obtained, there is no image contamination such as fogging, toner scattering and toner spent on a carrier are small, and an image having good fixability is obtained. Inorganic particles are used for the purpose of improving the impact resistance of the toner. An electrostatic charge image developing toner comprising a metal carbonate compound treated with at least a resin, a colorant and a fatty acid is disclosed (see Patent Document 2).

JP-A-63-139364 JP 7-72651 A

  However, the toners described in Patent Documents 1 and 2 are still not sufficient in low-temperature fixability and transferability.

  The present invention relates to an electrostatic charge image developing toner excellent in low-temperature fixability and transferability.

The present invention is an electrophotographic toner containing a binder resin including a crystalline resin and an amorphous resin, and calcium carbonate having a number average particle diameter of 1 nm to 500 nm,
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. The present invention relates to an electrophotographic toner containing a crystalline composite resin C containing a condensation resin component and a styrene resin component.

  The electrophotographic toner of the present invention exhibits excellent effects in low-temperature fixability and transferability.

  The toner for electrophotography of the present invention (hereinafter also simply referred to as toner) contains a binder resin containing a crystalline resin and an amorphous resin, and calcium carbonate. The crystalline resin is a long-chain fat. And a crystalline composite resin C containing a polycondensation resin component using a group monomer.

The reason why the electrophotographic toner of the present invention is excellent in low-temperature fixability and transferability is not clear, but can be considered as follows.
Although the crystalline resin obtained using a long-chain aliphatic monomer is excellent in low-temperature fixability, it has a problem that it is difficult to retain electric charge and transferability is lowered when exposed to the toner particle surface.
Thus, as a result of the study by the present inventors, as a crystalline resin, a crystalline composite resin C containing a polycondensation resin component and a styrene resin component using a long-chain aliphatic monomer, and calcium carbonate having a specific particle size It has been found that the combined use of and makes it easy to retain electric charge and improves transferability. This is because the crystalline composite resin C has a styrenic resin component, so that the chargeability is improved, and even if the crystalline composite resin C is exposed on the toner particle surface, the moisture resistance is improved by calcium carbonate. This is probably because the loss of charge is reduced and the charge is easily held.

  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 low-temperature fixability and transferability 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 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 transferability, preferably 10 or more, and from the viewpoint of heat resistant storage stability, 14 or less, and 12 or less. preferable.

  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 preferred from the viewpoint of improving the property and improving the low-temperature fixability, more preferably one or two selected from 1,10-decanediol and 1,12-dodecanediol, 1,12-dodecanediol is more preferred.

  The content of the aliphatic diol having 9 or more and 14 or less carbon atoms is preferably 70 mol% or more in the total amount of the dihydric or higher alcohol of the alcohol component from the viewpoint of improving the crystallinity of the composite resin and improving the low-temperature fixability. More preferably, it is 90 mol% or more, more preferably 95 mol% or more, preferably 100 mol% or less, more preferably substantially 100 mol%, still more preferably 100 mol%. Furthermore, from the viewpoint of increasing the crystallinity of the composite resin and improving the low-temperature fixability, one proportion 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, more preferably 90 mol% or more, further preferably 95 mol% or more, 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 low-temperature fixability of the toner, sebacic acid and dodecanedioic acid are used. One or two selected from the above 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.

  From the viewpoint of improving the crystallinity of the composite resin and improving the low-temperature fixability, the content of the aliphatic dicarboxylic acid compound having 9 to 14 carbon atoms in the total amount of the divalent or higher carboxylic acid compound in the carboxylic acid component, Preferably it is 70 mol% or more, more preferably 90 mol% or more, more preferably 95 mol% or more, preferably 100 mol% or less, more preferably substantially 100 mol%, still more preferably 100 mol%. .

  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 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 8 to 22 carbon atoms from the viewpoint of transferability and low-temperature fixability. It is preferable to contain at least one of the above monovalent aliphatic alcohols.

  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, and still more preferably 14 or more, from the viewpoint of transferability and low-temperature fixability. 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 transferability and low-temperature fixability, 1 mol% or more is preferable, 2 mol% or more is more preferable, and 3 mol% or more is more preferable. From the same viewpoint, it is preferably 12 mol% or less, more preferably 10 mol% or less, further preferably 8 mol% or less, and further preferably 6 mol% or less.

  Both reactive monomers described later are not included in the calculation of the content of the alcohol component or the carboxylic acid component. The same applies to the amorphous composite resin.

  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 94 mol% or more, from the viewpoint of improving the low-temperature fixability and transferability of the toner. Further, it is preferably 100 mol% or less, more preferably 99 mol% or less, still 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 from the viewpoint of increasing the crystallinity of the composite resin and improving the low-temperature fixability of the toner. In the total number of moles of the divalent or higher carboxylic acid compound in the carboxylic acid component which is the raw material component of the polycondensation resin component and the divalent or higher alcohol in the alcohol component, preferably 80 mol% or higher, more preferably It is 90 mol% or more, more preferably 95 mol% or more, preferably 100 mol% or less, more preferably substantially 100 mol%, 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 0.85 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 can be carried out in an inert gas atmosphere at a temperature of about 130 to 230 ° C. in the presence of an esterification catalyst, a polymerization inhibitor, etc. as necessary. it 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 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more from the viewpoint of transferability and durability in the raw material monomer of the styrene resin component. Moreover, 100 mass% or less is preferable, and substantially 100 mass% is more preferable.

  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.

  The content of the (meth) acrylic acid alkyl ester is preferably 30% by mass or less, more preferably 30% by mass or less, in the raw material monomer of the styrenic resin component, from the viewpoint of improving the transferability of the toner and the storage stability of the toner. Is 20% by mass or less, more preferably 10% by mass or less, preferably 0% by mass or more, and more preferably 0% by mass.

  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 low-temperature fixability and transferability of the toner, the crystalline composite resin C is used in addition to the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component, and further, 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 transferability 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 both reactive monomers used is preferably 1 mol or more, more preferably 2 mol or more, and still more preferably 4 mol with respect to a total of 100 mol of the alcohol component of the polycondensation resin component from the viewpoint of low-temperature fixability. From the viewpoint of transferability, it is preferably 30 mol or less, more preferably 20 mol or less, and still 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 of the styrenic resin component, from the viewpoint of low-temperature fixability. From the viewpoint of transferability, it is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less. 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 styrene resin component from the viewpoint of improving the low-temperature fixability and transferability 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 95/5 or less from the viewpoint of transferability, The following is more preferable, 85/15 or less is further preferable, and from the viewpoint of low-temperature fixability, 60/40 or more is preferable, 70/30 or more is more preferable, and 75/25 or more 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, but the amount of the polymerization initiator is included in the amount of the raw material monomer of the styrene resin component.

  The softening point of the crystalline composite resin C is preferably 105 ° C. or lower, more preferably 100 ° C. or lower, more preferably 96 ° C. or lower, from the viewpoint of low-temperature fixability, and preferably 70 ° C. or higher from the viewpoint of transferability. More preferably, it is 80 ° C. or higher.

  Further, 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 toner transferability. 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 loss elastic modulus (G ″) at 140 ° C. of the crystalline composite resin C is preferably 400 or less, more preferably 350 or less, further preferably 300 or less, and further preferably 250 or less, from the viewpoint of low-temperature fixability and transferability. Preferably, 200 or less is more preferable, 100 or less is more preferable, 50 or less is more preferable, 30 or less is more preferable, 20 or less is more preferable, and 5 or more is preferable and 7 or more is more preferable from the viewpoint of durability. As a method of adjusting the elastic modulus (G ″), a method of reducing the loss elastic modulus (G ″) by shortening the reaction time by using a monovalent carboxylic acid compound or alcohol, and increasing the reaction time. Thus, there is a method of increasing the loss elastic modulus (G ″).

  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 transferability 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 from the viewpoint of improving the low-temperature fixability of the toner and the transferability of the toner. 8 mass% or more is more preferable. 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 resin includes an amorphous composite resin AC including 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. It is preferable.

  Examples of the polycondensation resin component include polyester, polyester / polyamide, and the like. From the viewpoint of improving low-temperature fixability and transferability 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 formula (I):

(Wherein R ¹ O and OR ¹ are oxyalkylene groups, R ¹ is an ethylene and / or propylene group, x 1 and y 1 represent the average number of moles of alkylene oxide added, each being a positive number; The sum of x1 and y1 is preferably 1 or more, more preferably 1.5 or more, and preferably 16 or less, more preferably 8 or less, and even more 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), R ¹ O in the formula (I) such as polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane is propylene oxide. Addition of propylene oxide of bisphenol A, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, etc., and the addition of ethylene oxide of bisphenol A in which R ¹ O is ethylene oxide Thing etc. are mentioned.

  The content of the alkylene oxide adduct of bisphenol A represented by the formula (I) is preferably 70 mol% or more from the viewpoint of low-temperature fixability and transferability in the alcohol component of the amorphous composite resin AC. % 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 improving heat resistant storage stability and transferability.

  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 50 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more from the viewpoint of transferability in the carboxylic acid component of the amorphous composite resin AC. 85 mol% or more is more preferable.

  Other carboxylic acid components include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, an alkyl group having 1 to 30 carbon atoms, or 2 or more carbon atoms Aliphatic dicarboxylic acids such as succinic acid substituted with 30 or less alkenyl groups, cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid; trivalent or higher carboxylic acids such as trimellitic acid and pyromellitic acid; and of these acids Anhydride, alkyl (C1-3) ester; rosin; rosin modified with fumaric acid, maleic acid, acrylic acid and the like.

  The content of the trivalent or higher carboxylic acid compound is from the viewpoint of lowering the softening point, improving compatibility with the crystalline composite resin C, and improving low-temperature fixability and transferability with respect to 100 mol of the alcohol component. 10 moles or less, preferably 7 moles or less, more preferably 5 moles or less.

  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 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 1.00 or less, more preferably 0.95 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. 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 50% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, and more preferably 75% by mass or more from the viewpoint of transferability in the raw material monomer of the styrene resin component. More preferably, 80% by mass or more is further preferable, 82% by mass or more is further preferable, and from the viewpoint of low-temperature fixability, 95% by mass or less is preferable, 90% by mass or less is more preferable, and 87% by mass or less is more preferable.

  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 13% 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 transferability, 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 low-temperature fixability and transferability of the toner, the amorphous composite resin AC, in addition to the raw material monomer of the polycondensation resin component and the raw material monomer of the styrene resin component, is further a raw material of the polycondensation 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 AC, 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 AC 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. The resin component is more finely and uniformly dispersed.

  That is, from the viewpoint of improving the low-temperature fixability and transferability of the toner, the amorphous composite resin AC is (i ′) an alcohol component containing an alkylene oxide adduct of bisphenol A represented by the formula (I), A raw material monomer of a polycondensation resin component, including a carboxylic acid component containing an aromatic dicarboxylic acid compound, (b ') a raw material monomer of a styrene resin component, and (c') a raw material monomer of a polycondensation resin component, and A resin obtained by polymerizing amphoteric monomers capable of reacting with any of the raw material monomers of the styrenic resin component 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 both reactive monomers used is preferably 1 mol or more, more preferably 2 mol or more, and even more preferably 3 mol with respect to a total of 100 mol of the alcohol component of the polycondensation resin component from the viewpoint of low-temperature fixability. From the viewpoint of transferability, it is preferably 20 mol or less, more preferably 10 mol or less, and even more preferably 7 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 improving transferability, it is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less. 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 AC, the mass ratio of the polycondensation resin component and the styrene resin component (polycondensation resin component / styrene resin component) is preferably 60/40 or more from the viewpoint of low-temperature fixability, 70 / 30 or more is more preferable, 75/25 or more is more preferable, and from the viewpoint of transferability, 95/5 or less is preferable, 90/10 or less is more preferable, and 85/15 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, but the amount of the polymerization initiator is included in the amount of the raw material monomer of the styrene resin component.

  The softening point of the amorphous composite resin AC is preferably 80 ° C. or higher, more preferably 85 ° C. or higher, more preferably 90 ° C. or higher, further preferably 95 ° C. or higher, and more preferably 100 ° C. from the viewpoint of toner transferability. From the viewpoint of low-temperature fixability of the toner, it is preferably 125 ° C. or lower, more preferably 120 ° C. or lower, still more preferably less than 120 ° C., further preferably 117 ° C. or lower. When two or more kinds of amorphous composite resins AC are contained, the weighted average value of the softening points is preferably in the above range.

  The softening point of the amorphous composite resin AC is preferably higher than the softening point of the crystalline composite resin C from the viewpoints of low-temperature fixability and transferability. The difference in softening point between the amorphous composite resin AC and the crystalline composite resin C is preferably 50 ° C. or lower, more preferably 40 ° C. or lower, further preferably 30 ° C. or lower, and 26 ° C. or lower, from the viewpoint of low-temperature fixability. Further preferred. Further, from the viewpoint of transferability, 5 ° C or higher is preferable, 10 ° C or higher is more preferable, and 15 ° C or higher is more preferable. In the case where the amorphous composite resin AC and the crystalline composite resin C are composed of a plurality of resins, the difference between the softening points obtained by the weighted average is used.

  The maximum endothermic peak temperature of the amorphous composite resin AC is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, further preferably 60 ° C. or higher, from the viewpoint of toner transferability. 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.

  The glass transition temperature of the amorphous composite resin AC is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, from the viewpoint of toner transferability. 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 AC 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 amorphous resin preferably further contains an amorphous polyester AP obtained by polycondensation of an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound.

  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 (II) from the viewpoint of low-temperature fixability and transferability:

(Wherein R ² O and OR ² are oxyalkylene groups, R ² is an ethylene and / or propylene group, x 2 and y 2 are the average added moles of alkylene oxide, each being a positive number, The sum of x2 and y2 is preferably 1 or more, more preferably 1.5 or more, and preferably 16 or less, more preferably 8 or less, and even more preferably 4 or less)
It is preferable to contain the alkylene oxide adduct of bisphenol A represented by these. The alkylene oxide adduct of bisphenol A represented by the formula (II) used for the amorphous polyester AP is an alkylene oxide adduct of bisphenol A represented by the formula (I) used for the amorphous composite resin AC. They may be the same or different.

As the alkylene oxide adduct of bisphenol A represented by the formula (II), R ² O in the formula (II) such as polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane is propylene oxide. Addition of propylene oxide of bisphenol A, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, etc. In formula (II), R ² O is ethylene oxide. Thing etc. are mentioned.

  The content of the alkylene oxide adduct of bisphenol A represented by the formula (II) is preferably 70 mol% or more in the alcohol component of the amorphous polyester AP from the viewpoint of low temperature fixability and transferability, and 80 mol%. The above 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 transferability.

  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.

  In the carboxylic acid component of the amorphous polyester AP, the content of the aromatic dicarboxylic acid compound is preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, from the viewpoint of transferability. From the viewpoint of low-temperature fixability, 90 mol% or less is preferable, 80 mol% or less is more preferable, and 70 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 number of carbon atoms in the main chain of the aliphatic dicarboxylic acid compound is preferably 4 or more. 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. The carbon number of the main chain is the number of carbons located in a straight line between both carboxylic acids, and the succinic acid having an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms in the aforementioned side chain. The acid is an aliphatic dicarboxylic acid compound having 4 carbon atoms in the main chain.

  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), 1-20 carbon atoms in the side chain Examples thereof include succinic acid having an alkyl group or an alkenyl group having 2 to 20 carbon atoms, 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 5 mol% or more, more preferably 10 mol% or more, and even more preferably 12 mol% or more from the viewpoint of low-temperature fixability in the carboxylic acid component of the amorphous polyester AP. From the viewpoint of transferability, it is preferably 70 mol% or less, more preferably 60 mol% or less, and even more 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.

  The content of the trivalent or higher carboxylic acid compound is preferably 5 moles or more, more preferably 10 moles or more from the viewpoint of improving the softening point of the amorphous polyester and improving transferability with respect to 100 moles of the alcohol component. The amount is preferably 12 mol or more, more preferably 30 mol or less, and more preferably 25 mol or less from the viewpoint of low-temperature fixability.

  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 of the carboxylic acid component and the alcohol component (COOH group / OH group) is preferably 0.70 or more, more preferably 0.75 or more, preferably from the viewpoint of adjusting the softening point of the amorphous polyester AP. It is 1.00 or less, more preferably 0.95 or less.

  The polycondensation reaction of the raw material monomers can be performed in an inert gas atmosphere at a temperature of about 180 ° C. or more and 250 ° C. or less in the presence of an esterification catalyst, a polymerization inhibitor or the like, if necessary. 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.

  The softening point of the amorphous polyester AP is preferably 120 ° C. or higher, more preferably 125 ° C. or higher, more preferably 130 ° C. or higher, and preferably 170 ° C. or lower, from the viewpoint of improving toner transferability. More preferably, it is 160 degrees C or less, More preferably, it is 150 degrees C or less. When two or more kinds of amorphous polyester AP are contained, the weighted average value of the softening points is preferably in the above range.

  The softening point of the amorphous polyester AP is preferably higher than the softening point of the amorphous composite resin AC from the viewpoint of transferability, and the difference between the softening points of the amorphous polyester AP and the amorphous composite resin AC is: From the viewpoint of transferability, 10 ° C. or higher is preferable, 15 ° C. or higher is more preferable, 20 ° C. or higher is more preferable, 25 ° C. or higher is further preferable, and from the same viewpoint, 50 ° C. or lower is preferable, and 40 ° C. or lower is more preferable. 35 ° C. or lower is more preferable, and 30 ° C. or lower is more preferable. When the amorphous polyester AP and the amorphous composite resin AC are composed of a plurality of resins, the difference between the softening points obtained by the weighted average of each is taken.

  The maximum endothermic peak temperature of the amorphous polyester AP is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 60 ° C. or higher, from the viewpoint of toner transferability. 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.

  The glass transition temperature of the amorphous polyester AP is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 60 ° C. or higher, from the viewpoint of improving toner transferability. 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 polyester AP is preferably 40 mg KOH / g or less, more preferably 30 mg KOH / g or less, and further preferably 25 mg KOH / g or less, from the viewpoint of improving the environmental stability of the charge amount of the toner. , Preferably 1 mgKOH / g or more, more preferably 2 mgKOH / g or more.

  From the viewpoint of transferability, the mass ratio of the amorphous polyester AP to the amorphous composite resin AC (amorphous polyester AP / amorphous composite resin AC) is preferably 10 or less, more preferably 7 or less, and 5 or less. Is more preferably 3, or less, further preferably 2 or less, and from the same viewpoint, 0.1 or more is preferable, 0.3 or more is more preferable, 0.5 or more is further preferable, and 1 or more is more preferable.

  The mass ratio of the crystalline composite resin C to the total amount of the amorphous composite resin AC and the amorphous polyester AP (crystalline composite resin C / total amount of the amorphous composite resin AC and the amorphous polyester AP) is From the viewpoint of transferability, 30/70 or less is preferred, 25/75 or less is more preferred, 15/85 or less is more preferred, and from the viewpoint of low-temperature fixability, 3/97 or more is preferred, and 7/93 or more is more preferred. Preferably, 15/85 or more is more preferable.

  The toner of the present invention may contain an amorphous resin other than the amorphous composite resin AC and the amorphous polyester AP, for example, a composite resin, a vinyl resin, an epoxy resin, a polycarbonate resin, a polyurethane resin, and the like. The total content of the amorphous composite resin AC and the amorphous polyester AP is preferably 50% by mass or more, more preferably 80% by mass or more, and 90% by mass or more from the viewpoint of transferability in the amorphous resin. Further preferred. Moreover, 100 mass% or less is preferable and 100 mass% is more preferable.

  From the viewpoint of transferability, the mass ratio of the crystalline resin to the amorphous resin (crystalline resin / amorphous resin) is preferably 30/70 or less, more preferably 25/75 or less, and further 15/85 or less. Preferably, from the viewpoint of low-temperature fixability, 3/97 or more is preferable, 7/93 or more is more preferable, and 15/85 or more is more preferable.

  As for calcium carbonate, calcite (trigonal crystal), aragonite (orthorhombic crystal), and vaterite (hexagonal crystal) are known in the crystal structure. In the present invention, calcite is more stable at normal temperature and normal pressure. Those having a crystal structure mainly composed of are preferable.

  The number average particle size of calcium carbonate is 500 nm or less, preferably 200 nm or less, more preferably 100 nm or less, further preferably 50 nm or less, further preferably 40 nm or less, and more preferably 30 nm or less from the viewpoint of low-temperature fixability and transferability. More preferably, it is more preferably 25 nm or less, and from the same viewpoint, it is 1 nm or more, and preferably 10 nm or more.

  Calcium carbonate is preferably surface-treated with rosin from the viewpoint of improving transferability.

  Examples of fatty acids include caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, alginic acid, and behenic acid.

  The number of carbon atoms of the fatty acid is preferably 8 or more, more preferably 10 or more, and further preferably 12 or more, from the viewpoint of transferability. Further, from the viewpoint of availability, it is preferably 22 or less, and more preferably 18 or less.

  The rosin is preferably at least one selected from rosin acids such as hydrogenated rosin, polymerized rosin, and disproportionated rosin, metal salts thereof, and esters thereof.

Calcium carbonate surface-treated with a fatty acid, for example, as described in Japanese Patent Application Laid-Open No. 2004-123934, a hydrophobic fatty acid is directly added to a water slurry of calcium carbonate and heated to a melting point or higher to stir. After that, it is obtained by performing dehydration, drying, and powdering finish by a conventional method. In addition, calcium carbonate surface-treated with rosin is obtained by a wet method as described in, for example, JP-A No. 2003-26954.
The surface of calcium carbonate is preferably uniformly coated with fatty acid or rosin.

  The amount of calcium carbonate treated with a fatty acid or rosin varies depending on the particle size and the like and cannot be determined unconditionally. However, in general, the surface treatment amount of the fatty acid or rosin is based on 100 parts by mass of calcium carbonate, and the transferability of toner. From the viewpoint of increasing, preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, more preferably 2 parts by mass or more, from the same viewpoint, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, More preferably, it is 7 parts by mass or less.

  The content of calcium carbonate is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, still more preferably 25 parts by mass or less, and 15 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of low-temperature fixability. The following is more preferable, 7 parts by mass or less is further preferable, and from the viewpoint of transferability, 40 parts by mass or less is preferable, 30 parts by mass or less is more preferable, 25 parts by mass or less is further preferable, and 15 parts by mass or less is further preferable. Further, from the viewpoint of transferability, it is preferably 3 parts by mass or more, more preferably 7 parts by mass or more.

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

  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 preferred.

  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 improving the storage stability of the toner, it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and further preferably 7 parts by mass or less.

  Examples of mold release agents include polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax; aliphatic hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, sazol wax, and oxides thereof; carnauba wax , Montan waxes, and ester waxes such as deoxidized waxes and fatty acid ester waxes thereof; fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts, and the like. These may be used alone or in combination of two or more. Can be used.

  The melting point of the release agent is preferably 60 ° C. or more, more preferably 70 ° C. or more from the viewpoint of toner transferability, and preferably 160 ° C. or less, more preferably 140 ° C. or less, more preferably from the viewpoint of low-temperature fixability. Is 120 ° C. or lower, more preferably 110 ° C. or lower.

  The content of the release agent is preferably 0.5 parts by mass or more and more preferably 1 part by mass or more with respect to 100 parts by mass of the binder resin from the viewpoint of low-temperature fixability and transferability of the toner. Further, from the same viewpoint, it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and further 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.) and the like; styrene-acrylic resins such as “FCA-201-PS” and “FCA-701” PT "(manufactured by Fujikura Kasei Co., Ltd.).

  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. From the same viewpoint, the amount is preferably 10 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 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, but from the viewpoint of productivity and dispersibility of the colorant, A pulverized toner obtained by a melt kneading method is preferred. In the case of pulverized toner by the melt-kneading method, for example, a raw material such as a binder resin, calcium carbonate, a colorant, a release agent, and a charge control agent is uniformly mixed with a mixer such as a Henschel mixer, and then a sealed kneader, 1 It can be produced by melt-kneading with a screw or twin-screw extruder, an open roll kneader, etc., cooling, pulverizing and classifying.

  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 inorganic fine particles is preferably 5 nm or more, more preferably 10 nm or more, and further preferably 15 nm or more, from the viewpoint of the chargeability, fluidity, and transferability of the toner. Further, it is preferably 250 nm or less, more preferably 200 nm or less, and further preferably 90 nm or less.

  The average particle size of the organic fine particles is preferably 10 nm or more, and more preferably 100 nm or more, from the viewpoint of toner chargeability, fluidity, and transferability. Further, from the viewpoint of suppressing filming of the toner on the photoreceptor, it is preferably 1 μm or less, more preferably 800 nm or less, and even more preferably 600 nm or less.

  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 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, preferably 15 μm or less, and more preferably 10 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.

  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 “DSC Q20” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample was weighed into an aluminum pan, heated to 200 ° C., and the temperature decreasing rate was 10 Cool to 0 ° C at ℃ / 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)).

[Loss modulus of resin (G ")]
Loss elastic modulus (G ″) is measured with a viscoelasticity measuring device (rheometer) ARES (TA) (Strain: 1.0%, frequency: 6.28 rad / sec). A parallel plate with a diameter of 50 mm is heated to 160 ° C. Let stand, place 2 g of sample on a parallel plate at 160 ° C, sandwich between upper and lower plates, lower the temperature to 120 ° C, then increase the temperature to 160 ° C at 2 ° C / min, and determine the loss modulus at 140 ° C.

[Number average particle diameter of calcium carbonate]
It refers to the number average particle diameter of primary particles. Randomly measure the particle size of 500 particles (average value of major axis and minor axis) from a scanning electron microscope (SEM) photograph, and use them as the number average value.

[Melting point of release agent]
Using a differential scanning calorimeter “DSC Q20” (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. Then, cool to -10 ° C at a rate of 5 ° 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 of toner]
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. Determine the median particle size (D ₅₀ ).

Resin Production Example 1 [Resin C1]
The raw material monomer of the polycondensation resin component shown in Table 1 and the esterification catalyst are put into a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 160 ° C. The reaction was performed for 6 hours.
Then, the raw material monomer of styrene-type resin shown in Table 1 and both reactive monomers were dripped over 1 hour with the dropping funnel. After aging the addition polymerization reaction for 1 hour while maintaining at 160 ° C., the raw material monomer of the styrene resin was removed at 8.3 kPa for 1 hour. Further, the temperature was raised to 200 ° C. over 8 hours and reacted at 8.3 kPa for 1 hour to obtain a crystalline hybrid resin. Table 1 shows the physical properties of the obtained resin.

Resin Production Example 2 [Resin C2 to Resin C4]
The raw material monomer of the polycondensation resin component shown in Table 1 and the esterification catalyst are put into a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 160 ° C. The reaction was performed for 6 hours.
Then, the raw material monomer of styrene-type resin shown in Table 1 and both reactive monomers were dripped over 1 hour with the dropping funnel. After aging the addition polymerization reaction for 1 hour while maintaining at 160 ° C., the raw material monomer of the styrene resin was removed at 8.3 kPa for 1 hour. Further, the temperature was raised to 200 ° C. over 8 hours and reacted at 8.3 kPa for 2 hours to obtain a crystalline hybrid resin. Table 1 shows the physical properties of the obtained resin.

Resin Production Example 3 [Resin C5]
The raw material monomers shown in Table 1 and the esterification catalyst were placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, dehydration tube, stirrer, and thermocouple, and from 130 ° C to 200 ° C for 10 hours under a nitrogen atmosphere. The mixture was heated up and reacted at 200 ° C. and 8 kPa for 1 hour to obtain a crystalline polyester. Table 1 shows the physical properties of the obtained resin.

Resin Production Example 4 [Resin AC1 to Resin AC3]
The raw material monomer of the polycondensation resin component other than trimellitic anhydride shown in Table 2 and the esterification catalyst are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. The reaction was carried out at 12 ° C. for 12 hours and then at 8.3 kPa for 1 hour.
The temperature was lowered to 160 ° C., and the raw material monomer of styrene resin, the bireactive monomer, 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 160 ° C., the temperature was raised to 210 ° C., and the raw material monomer of the styrene resin was removed at 8.3 kPa for 1 hour.
Further, trimellitic anhydride was added at 210 ° C. and reacted until the desired softening point was reached to obtain an amorphous hybrid resin. Table 2 shows the physical properties of the obtained resin.

Resin Production Example 5 [Resin AP1, Resin AP2]
Raw material monomers and esterification catalysts other than trimellitic anhydride shown in Table 3 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple. The temperature was raised to 6 hours and allowed to react for 6 hours. After further heating to 210 ° C, trimellitic anhydride was added and reacted at normal pressure (101.3 kPa) for 1 hour, and further reacted at 40 kPa until the desired softening point was reached. Obtained. Table 3 shows the physical properties of the obtained resin.

Resin Production Example 6 [Resin AP3]
Raw material monomers other than trimellitic anhydride shown in Table 3, esterification catalyst, and polymerization inhibitor are placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. Under an atmosphere, the temperature was raised to 200 ° C. and reacted for 6 hours. After further heating to 210 ° C, trimellitic anhydride was added and reacted at normal pressure (101.3 kPa) for 1 hour, and further reacted at 40 kPa until the desired softening point was reached. Obtained. Table 3 shows the physical properties of the obtained resin.

Examples 1-16, Comparative Examples 1-4
Binder resin 100 parts by mass and calcium carbonate, charge control agent “Bontron N-04” (manufactured by Orient Chemical Co., Ltd.) 2.0 parts by mass, charge control resin “FCA-201-PS” (manufactured by Fujikura Kasei Co., Ltd.) 6.0 parts by weight, coloring agent “REGAL 330R” (Cabot Specialty Chemicals, Inc.) 6.0 parts by weight, and mold release agent “SP-105” (Kato Yoko, Fischer-Tropsch wax, melting point: 105 ° C.) 1.0 part by mass was mixed for 1 minute using a Henschel mixer and then melt-kneaded under the following conditions.

The same direction rotating twin screw extruder PCM-30 (manufactured by Ikekai Tekko Co., Ltd., shaft diameter 2.9 cm, shaft cross section 7.06 cm ² ) was used. Operating conditions are: barrel set temperature 100 ° C, shaft rotation speed 200r / min (shaft rotation peripheral speed 0.30m / sec), mixture supply speed 10kg / h (mixture supply rate per unit cross section of shaft 1.42kg / h)・ Cm ² ).

  The obtained kneaded product was cooled and coarsely pulverized by a pulverizer “Rotoplex” (manufactured by Hosokawa Micron), and a coarsely pulverized product having a particle size of 2 mm or less was obtained using a sieve having an opening of 2 mm. The obtained coarsely pulverized product was finely pulverized by adjusting the pulverization pressure so that the volume median particle size became 8.0 μm using a DS2 type impact plate airflow classifier (manufactured by Nippon Pneumatic Co., Ltd.). The resulting finely pulverized product is classified by adjusting the static pressure (internal pressure) so that the volume median particle size is 8.5 μm using a DSX2 type airflow classifier (manufactured by Nippon Pneumatic Co., Ltd.), and toner Particles were obtained.

  100 parts by mass of the toner particles obtained, and as an external additive, hydrophobic silica “R-972” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle size: 16 nm) 1.0 part by mass, hydrophobic silica “ TG-820F ”(manufactured by Cabot Specialty Chemicals Inc., hydrophobizing agent: HMDS, cyclic silazane, average particle size: 8 nm), 0.3 parts by mass, and polytetrafluoroethylene fine particles“ KTL-500F ”(Kitamura) A toner was obtained by mixing 0.4 parts by mass of an average particle size: 500 nm, manufactured by a company, at 2100 r / min (circumferential speed 29 m / sec) with a Henschel mixer (manufactured by Nihon Coke Kogyo Co., Ltd.) for 3 minutes.

  The details of the calcium carbonate used in Examples and Comparative Examples are shown in Table 4.

Test Example 1 [low temperature fixability]
A non-magnetic one-component developing device “HL-2040” (manufactured by Brother Industries, Ltd.), modified so that an unfixed image can be taken, was filled with toner, and a solid image of 2 cm square was printed. Using a non-magnetic one-component developing device "OKI MICROLINE 3010" (made by Oki Data Co., Ltd.) with an external fixing device, the fixing roller temperature can be increased from 100 ° C to 230 ° C at a fixing roller rotation speed of 120mm / sec. The unfixed image was fixed at each temperature while being raised by 5 ° C. to obtain a fixed image. The image obtained at each fixing temperature is rubbed 5 times with sand eraser (LION, ER-502R) applied with a load of 500 g, and the image density before and after rubbing is measured by the image density measuring instrument “GRETAG SPM50” (Gretag) ), The temperature at which the image density ratio before and after rubbing ([image density after rubbing / image density before rubbing] × 100) first exceeds 85% is defined as the minimum fixing temperature. did. The results are shown in Table 5. The lower the minimum fixing temperature, the better the low-temperature fixing property. The minimum fixing temperature is preferably 140 ° C. or lower, more preferably 135 ° C. or lower, and further preferably 130 ° C. or lower.

Test Example 2 [Transferability]
After mounting the toner in the HL-2040 toner cartridge manufactured by Brother Industries, and leaving it to stand for 24 hours under conditions of a temperature of 30 ° C and a humidity of 80%, the non-magnetic one-component developing device "HL-2040" (manufactured by Brother Industries, Ltd.) ) Was printed on a postcard paper, and the toner weight on the postcard was measured (T ₀ ). Then, after idling operation 0.5 hours 70r / min (36 ppm equivalent), it printed the same solid black image on postcard paper, was weighed toner weight on a postcard (T _P). The value obtained by T _P / T ₀ × 100 was defined as the transfer efficiency, and the transfer efficiency was continuously measured for 0.5 hour until the transfer efficiency reached 65% or less. The time during which the transfer efficiency was maintained at 65% or more (total idling time) was used as an index for transferability. The results are shown in Table 5. The longer the time until the transfer efficiency reaches 65% or less, the better the transfer blur, and the time is preferably 2.0 hours or more, more preferably 2.5 hours or more, and even more preferably 3.0 hours or more.

From the comparison of Examples 1 and 2, it can be seen that the lower the loss elastic modulus of the crystalline composite resin, the better the low-temperature fixability and transferability.
From the comparison of Examples 1 and 5, it can be seen that the more the aromatic dicarboxylic acid compound of the amorphous resin, the better the transferability.
From the comparison of Examples 1 and 6, it can be seen that the higher the styrene content in the styrene resin component of the amorphous composite resin, the better the transferability.
From the comparison of Examples 1, 7 and 8, in an amorphous resin, 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 The combination of an amorphous composite resin containing a non-crystalline polyester obtained by polycondensation of an alcohol component and a carboxylic acid component containing an aromatic dicarboxylic acid compound can be superior in low-temperature fixability and transferability. I understand.
In comparison with Examples 1, 10, and 12, it can be seen that Example 1 in which the number average particle diameter of calcium carbonate is 20 nm is superior in low-temperature fixability and transferability.
From the comparison between Examples 1 and 9, calcium carbonate has no difference in effect between the fatty acid treatment and the non-treatment, but from the comparison between Examples 10 and 11, it can be seen that the transferability is improved by the rosin treatment.
In contrast to Examples 1, 13, 14 and Comparative Example 3, the toner of Example 1 containing 5 parts by mass of calcium carbonate with respect to 100 parts by mass of the binder resin is superior in the balance between low-temperature fixability and transferability. I understand.
In comparison between Examples 1, 15, and 16, it can be seen that the toner of Example 1 having a crystalline resin / amorphous resin (mass ratio) of 10/90 is superior in terms of the balance between low-temperature fixability and transferability.
Since Comparative Example 1 contains crystalline polyester as the crystalline resin, the low-temperature fixability and transferability are reduced.
In Comparative Example 2, since the number average particle diameter of calcium carbonate is too large, the low-temperature fixability and transferability are deteriorated.
Since Comparative Example 3 does not use calcium carbonate, transferability is reduced.
Since Comparative Example 4 does not use a crystalline resin, the low-temperature fixability is lowered.

  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 comprising a binder resin including a crystalline resin and an amorphous resin, and calcium carbonate having a number average particle size of 1 nm to 500 nm in the toner particles ,
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. An electrophotographic toner containing a crystalline composite resin C containing a condensation resin component and a styrene resin component.   The toner for electrophotography according to claim 1, wherein the content of calcium carbonate is 3 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the binder resin.   The electrophotographic toner according to claim 1, wherein a mass ratio of the crystalline resin to the amorphous resin (crystalline resin / amorphous resin) is 3/97 or more and 30/70 or less.   The amorphous resin contains an amorphous composite resin AC including 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. The toner for electrophotography according to any one of claims 1 to 3. Amorphous resin further, an alcohol component, a carboxylic acid component containing an aromatic dicarboxylic acid compound polycondensed containing amorphous polyester AP obtained a toner for electrophotography according to claim 4, wherein.   The toner for electrophotography according to claim 5, wherein the softening point of the amorphous polyester AP is higher than the softening point of the amorphous composite resin AC.   The toner for electrophotography according to claim 1, wherein the loss elastic modulus at 140 ° C. of the crystalline composite resin C is 5 or more and 400 or less.   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 7, which is a resin obtained by applying the toner.