Toner

Abstract

To provide a toner that has good low temperature fixability and durability, and can prevent a gloss variation after storage in an environment where a large change in temperature and humidity repeatedly occurs.SOLUTION: A toner has a toner particle containing a binder resin. The binder resin contains a crystalline vinyl resin and an amorphous vinyl resin. The crystalline vinyl resin contains a specific monomer unit (a) having at least two alkyl groups having 16-30 carbon atoms in an amount of 5.0 mass% or more with respect to the mass of the crystalline vinyl resin. The amorphous vinyl resin contains a tetrahydrofuran insoluble.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a toner used in an electrophotographic method and an electrostatic recording method.

Background Art

[0002] Methods for visualizing image information using a toner such as the electrophotographic method are currently used in various fields, and improvements in performance such as higher image quality and energy savings are required. In the electrophotographic method, first, an electrostatic latent image is formed on an electrophotographic photoreceptor (image holding member) by a charging and exposure process. Next, the electrostatic latent image is developed with a developer containing toner, and a visualized image (fixed image) is obtained through a transfer process and a fixing process.

[0003] Among them, the fixing process is a process that requires relatively a lot of energy, and the development of a system and materials that achieve both energy savings and higher image quality has become an important technical issue. As an approach from the material aspect, a technique of using a crystalline resin for the binder resin of the toner has been studied. Since the molecular chains of the crystalline resin are regularly arranged, it hardly softens at temperatures lower than the melting point, so it has excellent heat storage stability. On the other hand, when the melting point is exceeded, the crystal melts rapidly, and a rapid decrease in viscosity accompanies it. Therefore, the crystalline resin is excellent in sharp meltability and has attracted attention as a material exhibiting low-temperature fixability.

[0004] As crystalline resins, there are known main-chain crystalline resins in which the main chain crystallizes, typified by crystalline polyesters, and side-chain crystalline resins in which the side chain crystallizes, typified by long-chain alkyl acrylate polymers. Among them, side-chain crystalline resins are known to exhibit excellent low-temperature fixability because they are easy to increase the degree of crystallinity, and have been widely studied. Examples of the side-chain crystalline resin include crystalline vinyl resins. The crystalline vinyl resin has a long-chain alkyl group as a side chain, and exhibits crystallinity by the orientation of the long-chain alkyl groups in the side chain. Patent Document 1 discloses a toner using a crystalline vinyl resin obtained by copolymerizing a polymerizable monomer having a long-chain alkyl group and an amorphous polymerizable monomer having a different SP value. On the other hand, a toner using a crystalline vinyl resin having a long-chain alkyl group in the side chain within the molecule has a problem of poor durability because the elastic modulus near room temperature is low, and toners with improved durability have been proposed.

[0005] Patent Document 2 discloses a toner using, as a binder resin, a copolymer of a composition containing a polymerizable monomer having a long-chain alkyl group, a second polymerizable monomer having a different SP value, and a polymerizable crosslinking agent. Further, Patent Document 3 discloses a toner using, as a binder resin, a melt-kneaded product of a crystalline vinyl resin having a long-chain alkyl group in the side chain within the molecule and an amorphous vinyl resin added with a polymerizable crosslinking agent. Further, Patent Document 4 discloses a toner using, as a binder resin, a resin having a crystalline vinyl resin portion having a long-chain alkyl group and an amorphous resin portion in which a vinyl resin having crystallinity and a polyester resin are crosslinked to each other by a carbon-carbon bond.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0007] In recent years, in addition to low-temperature fixability and durability, there has been an increasing demand for storage stability against severe temperature and humidity changes in toners. When transporting toner bottles or cartridges by sea, in situations where there is no temperature and humidity control such as in a dry container, they may be repeatedly exposed to high-temperature and low-temperature environments. For example, on a route passing directly under the equator, the environment is such that the temperature drops to around 22°C at night while rising to nearly 60°C during the day, and this cycle repeats daily. With the recent global warming, it is expected that the exposure environment will become even more severe in the future. As a result of investigations by the present inventors, it has been found that in toners containing the crystalline resin described in the prior art documents, the gloss of the fixed image before and after storage may change in an environment assuming a severe transportation environment. The toners described in Patent Documents 2 to 4 are characterized by containing a (meth)acrylate structure in which the crystalline resin has a long-chain alkyl group as a side chain and having a chemical crosslinked structure in the same main chain skeleton or a second resin skeleton. When the structure having a long-chain alkyl group as a side chain is a (meth)acrylate structure, since the distance from the surrounding long-chain alkyl groups is large, it is considered that molecular chain movement easily occurs due to temperature and humidity fluctuations. As a result, when stored in a severe transportation environment, it is considered that the crystalline resin is easily incorporated into the crosslinked portions in the same main chain skeleton or the second resin skeleton. From these points, the present inventors consider that the reason for the change in the gloss of the fixed image before and after storage in an environment where significant temperature and humidity changes occur is that the meltability of the toner changes because a part of the crystalline resin is incorporated into the crosslinked portions. From the above, further improvements are required to realize a toner having excellent low-temperature fixability and durability and suppressing gloss fluctuations in an environment where significant temperature and humidity changes occur. The present disclosure is directed to a toner having excellent low-temperature fixability and durability and capable of suppressing gloss fluctuations after storage in an environment where significant temperature and humidity changes occur.

Means for Solving the Problems

[0008] The above object is achieved by the following configuration. The present disclosure relates to a toner having toner particles containing a binder resin, wherein the binder resin contains a crystalline vinyl resin and an amorphous vinyl resin, the crystalline vinyl resin contains, based on the mass of the crystalline vinyl resin, 5.0% by mass or more of a monomer unit (a) represented by the following formula (1),

Chemical formula

Advantages of the Invention

[0009] According to the present disclosure, it is possible to provide a toner having excellent low-temperature fixability and durability and capable of suppressing gloss fluctuations after storage in an environment where significant temperature and humidity changes occur repeatedly.

Brief Description of the Drawings

[0010]

Figure 1

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the present invention will be described in detail with reference to preferred embodiments. In the present disclosure, descriptions such as "XX or more and YY or less" and "XX to YY" representing numerical ranges mean numerical ranges including the lower limit and the upper limit which are endpoints, unless otherwise specified. When numerical ranges are described stepwise, the upper and lower limits of each numerical range can be arbitrarily combined. Also, in the present disclosure, descriptions such as "at least one selected from the group consisting of XX, YY, and ZZ" mean any one of XX, YY, ZZ, the combination of XX and YY, the combination of XX and ZZ, the combination of YY and ZZ, or the combination of XX, YY, and ZZ. (Meta)acrylic ester means acrylic ester and / or methacrylic ester. "Monomer unit" refers to the reacted form of the monomer substance in a polymer. For example, in the main chain where the polymerizable monomer in the polymer has polymerized, one section of the carbon-carbon bond is regarded as one unit. The polymerizable monomer can be represented by the following formula (A).

Chemical formula

[0012] As described above, it has been found that toner containing a crystalline resin of the prior art may have a change in the gloss of the fixed image before and after storage in an environment where a significant temperature and humidity change occurs, assuming a harsh transportation environment. As a result of repeated studies by the present inventors to solve the above problems, by combining a crystalline vinyl resin having a specific monomer unit and an amorphous vinyl resin containing a tetrahydrofuran (THF) insoluble component as the binder resin constituting the toner particles, it has been found that a toner excellent in low-temperature fixability and durability and capable of suppressing gloss variation after storage in an environment where a significant temperature and humidity change occurs can be provided.

[0013] That is, the toner of the present disclosure is a toner having toner particles containing a binder resin, The binder resin contains a crystalline vinyl resin and an amorphous vinyl resin, The crystalline vinyl resin contains 5.0% by mass or more of a monomer unit (a) represented by the following formula (1) based on the mass of the crystalline vinyl resin,

Chemical formula

[0014] The inventors of the present invention consider the mechanism by which the above technical problems can be solved with the above configuration as follows. As described above, in the toner of the prior art, the binder resin constituting the toner particles has a crosslinked portion, and the crystalline resin constituting the binder resin contains a (meth)acrylate structure having a long-chain alkyl group as a side chain. When the toner of the prior art having such a configuration is stored in an environment where significant temperature and humidity changes occur repeatedly, the movement of the molecular chain is likely to occur, and a part of the crystalline resin is likely to be incorporated into the crosslinked portion, so that the gloss of the fixed image may change.

[0015] On the other hand, the toner according to the present disclosure contains a crystalline vinyl resin and an amorphous vinyl resin as the binder resin constituting the toner particles, and the crystalline vinyl resin contains a monomer unit (a) represented by the following formula (1).

Chemical formula

[0016] The amorphous vinyl resin contained in the binder resin contains a tetrahydrofuran-insoluble component. The fact that the amorphous vinyl resin contains a tetrahydrofuran-insoluble component means that the amorphous vinyl resin contains a physical crosslinked part or a chemical crosslinked part. The physical crosslinked part refers to a crosslinked part generated by the entanglement of the molecular chains of the high molecular weight amorphous vinyl resin. The chemical crosslinked part refers to a crosslinked part generated by adding a polyfunctional monomer. Since the amorphous vinyl resin contains a tetrahydrofuran-insoluble component, the elasticity of the toner is enhanced, and the toner is less likely to deteriorate even during long-term use, so excellent durability is ensured.

[0017] On the other hand, the crystalline vinyl resin contains the monomer unit (a) represented by the above formula (1). Thereby, the crystalline vinyl resin exhibits excellent low-temperature fixability peculiar to crystalline resins, and since long-chain alkyl groups contributing to the expression of crystallinity are present in close proximity to each other, it is considered that the crystal density increases and the molecular mobility decreases. Therefore, even in an environment where a large temperature and humidity change occurs, it becomes difficult for the crystalline vinyl resin to be incorporated into the crosslinked part of the amorphous vinyl resin, and a change in the meltability of the toner is less likely to occur. As a result, it is considered that the gloss variation of the fixed image after storage in an environment where a large temperature and humidity change occurs can be suppressed.

[0018] In this way, an attempt to control the crystal density by the distance between long-chain alkyl groups as side chains to suppress gloss variation in a harsh transportation environment where a large temperature and humidity change occurs has not been made conventionally. Due to the above mechanism, the toner of the present disclosure has excellent low-temperature fixability and durability, and can further suppress gloss variation after storage in a harsh environment where a large temperature and humidity change occurs. It is considered possible.

[0019] Hereinafter, the toner of the present disclosure will be described in detail. The toner has toner particles. <Toner particles> The toner particles contain a binder resin. The toner particles may contain, in addition to the binder resin, a release agent, a colorant, a charge control agent, and the like.

[0020] <Binder resin> The binder resin contains a crystalline vinyl resin and an amorphous vinyl resin. 〔Crystalline vinyl resin〕 The crystalline vinyl resin contains the monomer unit (a) represented by the above formula (1) in an amount of 5.0% by mass or more based on the mass of the crystalline vinyl resin.

[0021] When the content ratio of the monomer unit (a) represented by the above formula (1) based on the mass of the crystalline vinyl resin (hereinafter also referred to as ratio J) is less than 5.0% by mass, the gloss variation after storage in an environment where a large temperature and humidity change occurs cannot be sufficiently suppressed. When the ratio J is 5.0% by mass or more, it becomes difficult to be incorporated into the crosslinked portion of the amorphous vinyl resin, and the gloss variation of the fixed image after storage can be suppressed even in an environment where a large temperature and humidity change occurs. Further, when the ratio J is 5.0% by mass or more, excellent low-temperature fixability can be exhibited.

[0022] From the viewpoint of suppressing gloss variation, the ratio J is preferably 30.0% by mass or more, and more preferably 45.0% by mass or more. That is, it is preferable that the crystalline vinyl resin contains the monomer unit (a) in an amount of 30.0% by mass or more based on the mass of the crystalline vinyl resin. The upper limit of the ratio J is not particularly limited, but for example, it is preferably 5.0 to 100.0% by mass, more preferably 30.0 to 95.0, and even more preferably 45.0 to 90.0% by mass. Furthermore, from the viewpoint of suppressing gross fluctuations in an environment where significant temperature and humidity changes occur, the ratio J is preferably 0.7 mol% or more. For example, the ratio J is preferably 0.7 to 40.0 mol% in terms of molar ratio, more preferably 4.0 to 40.0 mol%, and even more preferably 20.0 to 35.0 mol%. The method for introducing the monomer unit (a) into the crystalline vinyl resin will be described later. Also, the ratio J can be controlled by the charged amount of raw materials when synthesizing the crystalline vinyl resin and the like.

[0023] In the above formula (1), R 1 ~R 4 Among them, at least two are each independently -X-COOR 5 , and the rest are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X is a single bond or an alkylene group having 1 or 2 carbon atoms, and R 5 is an alkyl group having 16 to 30 carbon atoms.

[0024] When such a structure is satisfied, it is excellent in low-temperature fixability and durability, and can highly suppress gross fluctuations after storage in an environment where significant temperature and humidity changes occur. Among R 1 to R 4 , when there is one part satisfying -X-COOR 5 and the rest are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, the gross fluctuations before and after the storage test cannot be sufficiently suppressed.

[0025] As a preferable substituent structure, among R 1 to R 4 , two (more preferably one of R 1 and R 2 , and one of R 3 and R 4 , a total of two) are each independently -X-COOR 5 , the rest are hydrogen atoms or methyl groups, X is a single bond or an alkylene group having 1 or 2 carbon atoms, and R 5 is more preferably an alkyl group having 16 to 30 carbon atoms. Also more preferably, X is a single bond.

[0026] R 5 When R is an alkyl group having 16 to 30 carbon atoms, the crystalline vinyl resin is likely to exhibit crystallinity, and a toner excellent in low-temperature fixability can be obtained. R 5 is preferably an alkyl group having 18 to 28 carbon atoms, and more preferably an alkyl group having 20 to 24 carbon atoms. R 5 The alkyl group of is preferably linear.

[0027] The binder resin preferably contains 20.0 to 80.0% by mass of the crystalline vinyl resin based on the mass of the binder resin (the content ratio of the crystalline vinyl resin based on the mass of the binder resin is hereinafter also referred to as ratio I). When ratio I is within the above range, it is easy to achieve both low-temperature fixability and the effect of suppressing gloss variation after storage in an environment where a large temperature and humidity change occurs. Ratio I is more preferably 25.0 to 70.0% by mass, and even more preferably 30.0 to 60.0% by mass. Ratio I can be controlled by the charged amount of the crystalline vinyl resin and the charged amounts of other materials during toner particle production.

[0028] The crystalline vinyl resin may or may not contain a monomer unit having an alkyl group having 16 to 30 carbon atoms different from the monomer unit (a) in addition to the monomer unit (a). In the crystalline vinyl resin, the content ratio of the monomer unit (a) among the monomer units having an alkyl group having 16 to 30 carbon atoms including the monomer unit (a) (hereinafter also referred to as ratio K) is preferably 50.0 to 100.0% by mass. Ratio K is more preferably 75.0 to 100.0% by mass, and even more preferably 90.0 to 100.0% by mass.

[0029] When ratio K is within the above range, even in an environment where a large temperature and humidity change occurs, the crystalline vinyl resin is less likely to be incorporated into the crosslinked portion of the amorphous vinyl resin, and the effect of suppressing gloss variation after storage is further enhanced.

[0030] In the case of a crystalline vinyl resin, as a method for introducing the monomer unit (a) represented by the formula (1), there is a method in which a polymerizable ester obtained by condensing a polyvalent carboxylic acid having 4 to 6 carbon atoms and having a carbon-carbon double bond and a monoalcohol having 16 to 30 carbon atoms and having a chain hydrocarbon group is used as a polymerizable monomer. The monomer unit (a) of the formula (1) may be used alone or in combination of two or more.

[0031] Examples of the polyvalent carboxylic acid having 4 to 6 carbon atoms and having a carbon-carbon double bond include maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, glutaconic acid, trans-aconitic acid, cis-aconitic acid and the like. Further, acid anhydrides and lower alkyl (1 to 4 carbon atoms) esters (for example, methyl ester, ethyl ester, isopropyl ester, etc.) of these polyvalent carboxylic acids may be used. The polyvalent carboxylic acid may be used alone or in combination of two or more. Among these, from the viewpoint of suppressing gloss fluctuation after storage in an environment where significant temperature and humidity changes occur, it is preferably at least one selected from the group consisting of maleic acid, fumaric acid, itaconic acid and their acid anhydrides.

[0032] Examples of the monoalcohol having 16 to 30 carbon atoms and having a chain hydrocarbon group include alcohols having a linear alkyl group (alkyl group having 16 to 30 carbon atoms) (such as cetanol, stearyl alcohol, 1-eicosanol, behenyl alcohol, 1-tetracosanol and 1-triacontanol) and alcohols having a branched alkyl group (alkyl group having 16 to 30 carbon atoms) (such as 2-decyl-1-tetradecanol). Among these, from the viewpoint of crystallinity, it is preferably an alcohol having a linear alkyl group (alkyl group having 16 to 30 carbon atoms). More preferably, it is an alcohol having a linear alkyl group (alkyl group having 18 to 28 carbon atoms), and still more preferably, it is an alcohol having a linear alkyl group (alkyl group having 20 to 24 carbon atoms).

[0033] The method for producing the above-mentioned polymerizable ester is not particularly limited except for condensing a polyvalent carboxylic acid having 4 to 6 carbon atoms and having a carbon-carbon double bond with a monoalcohol having 16 to 30 carbon atoms and having a chain hydrocarbon group. In order to ensure the condensation reaction and prevent the reaction of the carbon-carbon double bond during the production of the above-mentioned polymerizable ester, it is preferable to use an esterification catalyst or a stabilizer (polymerization inhibitor).

[0034] The crystalline vinyl resin preferably contains a monomer unit corresponding to methacrylonitrile. The crystalline vinyl resin preferably contains 1.0 to 25.0% by mass of the monomer unit corresponding to methacrylonitrile, and more preferably contains 10.0 to 20.0% by mass. Also, the crystalline vinyl resin preferably contains a monomer unit corresponding to styrene. The crystalline vinyl resin preferably contains 1.0 to 60.0% by mass of the monomer unit corresponding to styrene, and more preferably contains 4.0 to 10.0% by mass.

[0035] From the viewpoints of improving the low-temperature fixing property due to the crystallization and suppressing the gloss variation after storage in an environment where a large temperature and humidity change occurs, the acid value of the crystalline vinyl resin is preferably 3.0 mgKOH / g or less. The acid value of the crystalline vinyl resin is more preferably 0.0 to 2.0 mgKOH / g, and even more preferably 0.1 to 1.0 mgKOH / g. The fact that the acid value is 3.0 mgKOH / g or less indicates that there are few unreacted sites when synthesizing the crystalline vinyl resin. That is, since there are few sites without a monoalcohol, it is considered that the crystal density is high. In order to control the acid value within the above range, it can be controlled by the ratio of carboxylic acid and alcohol when synthesizing the crystalline resin.

[0036] In addition to the monomer unit (a) represented by the formula (1), the crystalline vinyl resin may contain other monomer units. As a method for introducing other monomer units, there is a method of polymerizing the above-mentioned polymerizable ester and other vinyl monomers.

[0037] Examples of other vinyl monomers include the following. Styrene, α-methylstyrene, (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Monomers having a urea group: for example, amines having 3 to 22 carbon atoms [primary amines (such as normal butylamine, t-butylamine, propylamine, and isopropylamine), secondary amines (such as di-normal ethylamine, di-normal propylamine, and di-normal butylamine), aniline, and cyclohexylamine, etc.], and monomers obtained by reacting an isocyanate having 2 to 30 carbon atoms with an ethylenically unsaturated bond with the above amines by a known method. Monomers having a carboxy group; for example, methacrylic acid, acrylic acid, 2-carboxyethyl (meth)acrylate, etc. Monomers having a hydroxy group; for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc. Monomers having an amide group; for example, acrylamide, monomers obtained by reacting an amine having 1 to 30 carbon atoms with a carboxylic acid having 2 to 30 carbon atoms with an ethylenically unsaturated bond (such as acrylic acid and methacrylic acid) by a known method. Monomers having a lactam structure; for example, N-vinyl-2-pyrrolidone, etc.

[0038] Among them, it is preferable that the crystalline vinyl resin contains, in addition to the monomer unit (a), a monomer unit (b) different from the monomer unit (a). When the SP value of the monomer unit (a) is SPa (J / cm 3 ) 0.5 and the SP value of the monomer unit (b) is SPb (J / cm 3 ) 0.5 it is preferable that the SPa and the SPb satisfy the following formula (2). However, when there are two or more other monomer units used in addition to the monomer unit (a) represented by the formula (1), among these, the one with the largest difference from the SP value of the monomer unit (a) is defined as the monomer unit (b). 3.0 ≦ |SPb - SPa| ≦ 21.0 ··· Formula (2)

[0039] When the relationship between the SP value SPa of the monomer unit (a) and the SP value SPb of the monomer unit (b) is within the above range, the crystalline sites and amorphous sites in the crystalline vinyl resin are likely to form a distinct phase separation state, so that appropriate crystallinity can be maintained. Furthermore, it is more preferable that the relationship between the SP value SPa of the monomer unit (a) and the SP value SPb of the monomer unit (b) satisfies the formula (3). 7.0 ≦ |SPb - SPa| ≦ 12.0 ··· Formula (3)

[0040] SPa (J / cm 3 ) 0.5 is preferably from 15.0 to 21.0, more preferably from 16.0 to 18.5. SPb (J / cm 3 ) 0.5 is preferably from 20.0 to 40.0, more preferably from 25.0 to 30.0. Also, it is preferable that SPb ≧ Spa.

[0041] The crystalline vinyl resin may be produced by any known method as long as it is within the scope of the present configuration, but it is preferably produced by polymerizing a composition of a polymerizable monomer containing the above polymerizable ester with an initiator or the like.

[0042] As the polymerization initiator, it is possible to use a known polymerization initiator. For example, azo or diazo polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; peroxide polymerization initiators such as benzoyl peroxide, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxydicarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide can be mentioned. Also, known chain transfer agents and polymerization inhibitors may be used.

[0043] [Amorphous vinyl resin] The binder resin contains an amorphous vinyl resin. The amorphous vinyl resin contains a tetrahydrofuran-insoluble component. The amorphous vinyl resin is preferably a synthetic resin in which the main chain is bonded by vinyl polymerization. Examples of the polymerizable monomer used for the amorphous vinyl resin include styrene derivatives such as α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene; (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate ((meth)acrylic acid -n-butyl, (meth)acrylic acid -t-butyl, etc.), 2-ethylhexyl (meth)acrylate; acrylonitrile, methacrylonitrile, (meth)acrylic acid, etc. The amorphous vinyl resin (B) is preferably a polymer of a monomer mixture containing styrene and butyl (meth)acrylate. The content ratio of the amorphous vinyl resin based on the mass of the binder resin is not particularly limited, but for example, 1.0 to 80.0% by mass is preferable, and 5.0 to 70.0% by mass is more preferable.

[0044] The binder resin preferably contains 2.0 to 50.0% by mass of tetrahydrofuran-insoluble matter based on the mass of the binder resin. Hereinafter, the content ratio of the tetrahydrofuran-insoluble matter in the binder resin is also referred to as ratio L. Ratio L is more preferably 5.0 to 40.0% by mass, and even more preferably 10.0 to 30.0% by mass. When ratio L is within the above range, excellent low-temperature fixability and durability can be achieved simultaneously.

[0045] In addition, the crystalline vinyl resin preferably contains 5.0 to 100.0% by mass of tetrahydrofuran-insoluble matter based on the mass of the crystalline vinyl resin. Hereinafter, the content ratio of the tetrahydrofuran-insoluble matter in the crystalline vinyl resin is also referred to as ratio M. Ratio M is more preferably 10.0 to 95.0% by mass, and even more preferably 20.0 to 90.0% by mass. When the content of the tetrahydrofuran-insoluble matter is within the above range, it is easier to achieve both low-temperature fixability, durability, and the effect of suppressing gloss fluctuations after storage in an environment where significant temperature and humidity changes occur.

[0046] The tetrahydrofuran-insoluble matter of the amorphous vinyl resin may be formed by the entanglement of the molecular chains of the high-molecular-weight amorphous vinyl resin, that is, physical cross-linking, or may be formed by chemical cross-linking obtained by adding a polyfunctional monomer such as a cross-linking agent. The amorphous vinyl resin is a polymer of a composition containing a polymerizable monomer and a cross-linking agent, and it is preferable that the cross-linking agent has two or more polymerizable double bonds. When the amorphous vinyl resin has the above configuration, excellent durability and suppression of gloss fluctuations in an environment where significant temperature and humidity changes occur can be achieved simultaneously.

[0047] The following cross-linking agents having two or more polymerizable double bonds are preferably used. Aromatic divinyl compounds (divinylbenzene, divinylnaphthalene); Diacrylate compounds linked by an alkyl chain (ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol acrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and those obtained by replacing these acrylates with methacrylates); Diacrylate compounds linked by an alkyl chain containing an ether bond (for example, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol #400 diacrylate, polyethylene glycol #600 diacrylate, dipropylene glycol diacrylate, and those obtained by replacing these acrylates with methacrylates); Diacrylate compounds linked by a chain containing an aromatic group and an ether bond [polyoxyethylene(2)-2,2-bis(4-hydroxyphenyl)propane diacrylate, polyoxyethylene(4)-2,2-bis(4-hydroxyphenyl)propane diacrylate, and those obtained by replacing these acrylates with methacrylates]; Polyester-type diacrylate compounds, etc.

[0048] Examples of the polyfunctional crosslinking agents include the following. Pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, and those obtained by replacing these acrylates with methacrylates; Triallyl cyanurate, tri allyl trimellitate, etc.

[0049] Among these crosslinking agents, aromatic divinyl compounds (especially divinylbenzene) and diacrylate compounds linked by a chain containing an aromatic group and an ether bond are preferred, and diacrylate compounds linked by a chain containing an aromatic group and an ether bond are more preferred. As the crosslinking agent, for example, 1,6-hexanediol diacrylate is preferred. The crosslinking agent can preferably be used in an amount of 0.01 to 10.00 parts by mass, more preferably 0.03 to 5.00 parts by mass, per 100 parts by mass of the polymerizable monomer component other than the crosslinking agent.

[0050] The amorphous vinyl resin preferably does not contain the monomer unit (a) represented by the formula (1).

[0051] <Release agent> The toner particles may contain a release agent. The release agent is preferably at least one selected from the group consisting of hydrocarbon waxes and ester waxes. By using a hydrocarbon wax and / or an ester wax, it becomes easier to ensure effective releasability.

[0052] The hydrocarbon wax is not particularly limited, and examples thereof include the following. Aliphatic hydrocarbon waxes: low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymers, Fischer-Tropsch waxes, or waxes obtained by oxidizing or adding an acid thereto.

[0053] The ester wax only needs to have at least one ester bond in one molecule, and either natural ester wax or synthetic ester wax may be used. The ester wax is not particularly limited, and examples thereof include the following. Esters of monohydric alcohols and monocarboxylic acids such as behenyl behenate, stearyl stearate, and palmityl palmitate; Esters of dibasic carboxylic acids and monohydric alcohols such as dibehenyl sebacate; Esters of dihydric alcohols and monocarboxylic acids such as ethylene glycol distearate and hexanediol dibehenate; Esters of trihydric alcohols and monocarboxylic acids such as glycerin tribehenate; Esters of tetrahydric alcohols and monocarboxylic acids such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate; Esters of hexavalent alcohols such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, dipentaerythritol hexabehenate and monocarboxylic acids; Esters of polyfunctional alcohols such as polyglycerol behenate and monocarboxylic acids; natural ester waxes such as carnauba wax and rice wax. Among them, esters of hexavalent alcohols such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, dipentaerythritol hexabehenate and monocarboxylic acids, and esters of octavalent alcohols such as tripentaerythritol hexastearate, tripentaerythritol hexapalmitate, tripentaerythritol hexabehenate and monocarboxylic acids are preferred.

[0054] In the toner, the content of the release agent in the toner particles is preferably 1.0 to 30.0% by mass, more preferably 2.0 to 25.0% by mass. When the content of the release agent in the toner particles is within the above range, the releasability during fixing is easily ensured. The melting point of the release agent is preferably 60 to 120°C. When the melting point of the release agent is within the above range, it is easily melted during fixing and oozes out onto the surface of the toner particles, and the releasability is easily exhibited. The melting point of the release agent is more preferably 70 to 100°C.

[0055] <Colorant> The toner particles may contain a colorant. Examples of the colorant include known organic pigments, organic dyes, inorganic pigments, carbon black as a black colorant, and magnetic particles. In addition, colorants conventionally used in toners may also be used.

[0056] Examples of yellow colorants include the following: condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, C.I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, 180 are preferably used.

[0057] Examples of magenta colorants include the following: condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, C.I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254 are preferably used.

[0058] Examples of cyan colorants include the following: copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specifically, C.I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, 66 are preferably used.

[0059] The colorant is selected from the viewpoints of hue angle, chroma, lightness, lightfastness, OHP transparency, and dispersibility in the toner. The content of the colorant is preferably 1.0 to 20.0 parts by mass with respect to 100.0 parts by mass of the binder resin. When magnetic particles are used as the colorant, the content is preferably 40.0 to 150.0 parts by mass with respect to 100.0 parts by mass of the binder resin.

[0060] <Charge control agent> The toner particles may contain a charge control agent as necessary. Also, the charge control agent may be externally added to the toner particles. By blending the charge control agent, the charge characteristics can be stabilized and the optimum triboelectric charge amount can be controlled according to the developing system. As the charge control agent, known ones can be used, and in particular, a charge control agent with a fast charging speed and the ability to stably maintain a certain charge amount is preferred.

[0061] Examples of the charge control agent for controlling the toner to be negatively chargeable include the following. Organometallic compounds and chelate compounds are effective, and examples include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Examples of the charge control agent for controlling the toner to be positively chargeable include the following. Examples include nigrosine, quaternary ammonium salts, metal salts of higher fatty acids, diorganotin borates, guanidine compounds, and imidazole compounds. The content of the charge control agent is preferably 0.01 to 20.0 parts by mass, more preferably 0.5 to 10.0 parts by mass, based on 100.0 parts by mass of the toner particles.

[0062] <Method for Producing Toner Particles> The method for producing the toner particles is not particularly limited, and any known method such as suspension polymerization, emulsion aggregation, dissolution suspension, and crushing method may be adopted. The toner particles are preferably produced by the suspension polymerization method. The toner particles are preferably suspension polymerization toner particles.

[0063] The suspension polymerization method will be described in detail. For example, a pre-synthesized crystalline vinyl resin is added to a mixture of polymerizable monomers for producing, for example, an amorphous vinyl resin. If necessary, other materials such as a colorant, a release agent, and a charge control agent are added and uniformly dissolved or dispersed to prepare a polymerizable monomer composition. Thereafter, the polymerizable monomer composition is dispersed in an aqueous medium using a stirrer or the like to prepare suspension particles of the polymerizable monomer composition. Then, the polymerizable monomer contained in the particles is polymerized by an initiator or the like to obtain toner particles. After the polymerization is completed, the toner particles can be filtered, washed, and dried by known methods. Further, an external additive or the like may be added as necessary to obtain the toner.

[0064] As the polymerization initiator, a known polymerization initiator can be used. For example, azo or diazo polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; peroxide-based polymerization initiators such as benzoyl peroxide, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxy pivalate, t-butyl peroxy isobutyrate, t-butyl peroxy neodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, etc. can be mentioned. Also, known chain transfer agents and polymerization inhibitors may be used.

[0065] The aqueous medium may contain an inorganic or organic dispersion stabilizer. As the dispersion stabilizer, a known dispersion stabilizer can be used. Examples of the inorganic dispersion stabilizer include phosphates such as hydroxyapatite, tricalcium phosphate, dicalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate; carbonates such as calcium carbonate, magnesium carbonate; metal hydroxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide; sulfates such as calcium sulfate, barium sulfate; calcium metasilicate; bentonite; silica; alumina, etc.

[0066] On the one hand, examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salts, starch, and the like.

[0067] When using an inorganic compound as the dispersion stabilizer, a commercially available product may be used as it is, or in order to obtain finer particles, the inorganic compound may be generated in an aqueous medium and then used. For example, in the case of calcium phosphate such as hydroxyapatite or tricalcium phosphate, it is advisable to mix an aqueous phosphate solution and an aqueous calcium salt solution under high stirring.

[0068] The aqueous medium may contain a surfactant. As the surfactant, a known surfactant can be used. Examples include anionic surfactants such as sodium dodecylbenzenesulfate and sodium oleate; cationic surfactants; amphoteric surfactants; nonionic surfactants, and the like.

[0069] <External additive> The toner may use toner particles as the toner as they are, or if necessary, by mixing external additives and the like and adhering them to the surface of the toner particles, it can also be used as a toner. Examples of external additives include inorganic fine particles selected from the group consisting of silica fine particles, alumina fine particles, and titania fine particles, or their composite oxides. Examples of composite oxides include silica-aluminum fine particles and strontium titanate fine particles. The content of the external additive is preferably 0.01 to 8.0 parts by mass, and more preferably 0.1 to 4.0 parts by mass with respect to 100 parts by mass of toner particles.

[0070] The calculation methods and measurement methods for various physical properties of the toner and toner materials are described below. <Measurement method of differential scanning calorimetry (DSC)> The endothermic peak temperature and exothermic peak temperature of the crystalline resin and the release agent are measured in accordance with ASTM D3418-82 using a differential scanning calorimeter "Q1000" (manufactured by TA Instruments). The temperature correction of the device detection part uses the melting points of indium and zinc, and the heat of fusion of indium is used for the heat correction. When measuring the toner, first accurately weigh 10 mg of the toner, put it into an aluminum pan, and use an empty aluminum pan as a reference. In the first heating process, the measurement is carried out while heating the measurement sample from 20 °C to 180 °C at a rate of 10 °C / min to obtain a differential scanning calorimetry curve A. Then, after holding at 180 °C for 10 minutes, the measurement is carried out while performing a cooling process of cooling from 180 °C to 10 °C at a rate of 10 °C / min to obtain a differential scanning calorimetry curve B. Further, after holding at 10 °C for 10 minutes, in the second heating process, the measurement is carried out while heating again from 10 °C to 180 °C at a rate of 10 °C / min to obtain a differential scanning calorimetry curve C. The temperature of the peak top of the peak appearing in the obtained differential scanning calorimetry curve C is obtained and taken as the peak temperature.

[0071] <Method for Separating Toner Particles from Toner> When analyzing the toner particles, if the surface of the toner particles is treated with an external additive or the like, the external additive is separated by the following method to obtain the toner particles. Add 160 g of sucrose (manufactured by Kishida Chemical) to 100 mL of ion-exchanged water and dissolve it while stirring with hot water to prepare a thick sucrose solution. Put 31 g of the above thick sucrose solution and 6 mL of Contaminon N (a 10% by mass aqueous solution of a neutral detergent for precision measuring instrument cleaning with a pH of 7 composed of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) into a centrifuge tube to prepare a dispersion. Add 1.0 g of the toner to this dispersion and loosen the toner lumps with a spatula or the like. Shake the centrifuge tube with a shaker (sold by AS ONE Corporation) at 350 spm (strokes per min) for 20 min. After shaking, transfer the solution to a glass tube (50 mL) for a swing rotor and use a centrifuge (H-9R Separate at 3500 rpm for 30 minutes using Kokusan Co., Ltd. Through this operation, the toner particles and the detached external additives are separated. Visually confirm that the toner particles and the aqueous solution are sufficiently separated, and collect the separated toner particles in the uppermost layer with a spatula or the like. After filtering the collected toner with a vacuum filter, dry it with a dryer for 1 hour or more to obtain toner particles. Repeat this operation multiple times to ensure the required amount.

[0072] <Method for Separating Tetrahydrofuran (THF) Insoluble Matter> Precisely weigh 1.5 g of toner particles for measuring the THF insoluble content (0.7 g when measuring the THF insoluble content of the resin alone) (W [g]), put it into a pre-precise cylindrical filter paper (product name: No. 86R, size 28 × 100 mm, manufactured by Advantec Toyo Co., Ltd.), and set it in a Soxhlet extractor. Extract for 18 hours using 200 mL of tetrahydrofuran (THF) as the solvent, and perform the extraction at a reflux rate such that the extraction cycle of the solvent is once every 5 minutes. After the extraction is completed, take out the cylindrical filter paper, air-dry it, and then vacuum-dry it at 40 °C for 8 hours to obtain the extraction residue. Weigh the mass of the cylindrical filter paper containing the extraction residue, and subtract the mass of the cylindrical filter paper to calculate the mass of the extraction residue (W2 [g]). On the other hand, sufficiently distill off the THF from the soluble components in THF with an evaporator to obtain the THF soluble components. Let the mass of the obtained THF soluble components be W1 [g]. Next, calculate the mass of the components other than the resin in the extraction residue by the following procedure. Put the THF extraction residue (W2 [g]) into a pre-weighed 30 ml magnetic crucible. Put the crucible into an electric furnace, heat it at 900 °C for 3 hours, let it cool in the electric furnace, and then let it cool in a desiccator at room temperature for 1 hour or more. After cooling, weigh the mass of the crucible containing the incineration residual ash, and subtract the mass of the crucible to calculate the mass of the incineration residual ash (W22 [g]). Here, the residual ash after incineration is the component other than the resin in the extraction residue. That is, W22 [g] is the mass of the component other than the resin in the extraction residue. Then, calculate the mass of the resin component contained in the extraction residue (W2 [g]) by the following formula (9). Let this be the mass of the THF insoluble content (W21 [g]). W21 = W2 - W22 ··· Equation (9)

[0073] In addition, for the recovered THF-insoluble matter, DSC measurement is performed by the above-described method. When there is no melting point peak, it can be determined that the THF-insoluble matter is an amorphous resin. Furthermore, by combining known methods such as Fourier transform infrared spectroscopy and pyrolysis gas chromatography for the THF-insoluble matter, the constituent components of the THF-insoluble matter can be analyzed.

[0074] <Method for Separating Crystalline Vinyl Resin and Amorphous Vinyl Resin from Toner Particles> Separation of crystalline vinyl resin and amorphous vinyl resin from toner particles can be achieved by known methods, and an example is shown below. As a method for separating the resin component from toner particles, gradient LC is used. In this analysis, regardless of the molecular weight, separation can be performed according to the polarity of the resin in the binder resin. In the present invention, since the toner particles contain a THF-insoluble matter, they are separated into a THF-insoluble matter and a THF-soluble matter according to the aforementioned <Separation Method of Tetrahydrofuran (THF)-Insoluble Matter>. Next, the THF-soluble matter is dissolved in chloroform. The sample was adjusted so that the sample concentration was 0.1% by mass in chloroform, and the solution filtered through a 0.45 μm PTFE filter was used for measurement. The gradient polymer LC measurement conditions are shown below. Apparatus: UlTIMATE3000 (manufactured by Thermo Fisher Scientific) Mobile phase: A Chloroform (HPLC), B Acetonitrile (HPLC) Gradient: 2 min (A / B = 0 / 100) → 25 min (A / B = 100 / 0) (Note that the gradient of the change in the mobile phase was made linear.) Flow rate: 1.0 mL / min Injection: 0.1% by mass × 20 μL Column: Tosoh TSKgel ODS (4.6 mm φ x 150 mm x 5 μm) Column temperature: 40°C Detector: Corona Charged Particle Detector (Corona-CAD) (manufactured by Thermo Fisher Scientific) Regarding the time-intensity graph obtained by measurement, the resin components can be separated into two peaks according to polarity. Then, the above measurement is performed again, and by fractionating at the time corresponding to the valley of each peak, it is possible to separate into two types of resins. For the separated resins, DSC measurement is performed, and the resin with a melting point peak is defined as a crystalline vinyl resin (mass W11 [g]), and the resin without a melting point peak is defined as an amorphous vinyl resin (mass W12 [g]).

[0075] In addition, when the toner particles contain a release agent, it is necessary to separate the release agent from the toner particles in advance. Separation of the release agent is performed by recycling HPLC to separate components with a molecular weight of 3000 or less as the release agent. Note that the molecular weight at the time of separation can be changed according to the molecular weight of the release agent. The measurement method is shown below. First, prepare a chloroform solution of the toner by the method described above. Then, filter the obtained solution through a solvent-resistant membrane filter "Microlidisk" (manufactured by Tosoh Corporation) with a pore size of 0.2 μm to obtain a sample solution. Note that the sample solution is adjusted so that the concentration of the components soluble in chloroform is 1.0 mass%. Using this sample solution, measurement is performed under the following conditions. · Apparatus: LC-Sakura NEXT (manufactured by Japan Analytical Industry Co., Ltd.) · Column: JAIGEL2H, 4H (manufactured by Japan Analytical Industry Co., Ltd.) · Eluent: Chloroform · Flow rate: 10.0 ml / min · Oven temperature: 40.0 °C · Sample injection volume: 1.0 ml When calculating the molecular weight of the sample, a molecular weight calibration curve prepared using a standard polystyrene resin (for example, trade names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used. From the molecular weight curve thus obtained, the components with a molecular weight of 3000 or less are repeatedly fractionated to remove the release agent (mass W3 [g]) from the toner particles.

[0076] <Measurement of the content ratio of each component in the toner particles> From each mass described in the above <Separation method of tetrahydrofuran (THF) insoluble matter> and <Separation method of crystalline vinyl resin and amorphous vinyl resin from toner particles>, the content ratio of each component in the toner particles is calculated as follows. 〔Mass ratio of crystalline vinyl resin based on the mass of the binder resin: Ratio I (unit: mass%)〕 Ratio I = (W11 / (W11 + W12 + W21 - W3)) × 100 ··· Formula (4) 〔Mass ratio of THF insoluble matter based on the mass of the binder resin: Ratio L (unit: mass%)〕 Ratio L = (W2 / (W11 + W12 + W21 - W3)) × 100 ··· Formula (5) 〔Mass ratio of THF insoluble matter based on the mass of the crystalline vinyl resin: Ratio M (unit: mass%)〕 Ratio M = (W21 / W11) × 100 ··· Formula (6)

[0077] <Measurement method of the content ratio of various monomer units such as monomer unit (a) in the resin and the number of carbon atoms of the alkyl group> The measurement of the content ratio of various monomer units such as monomer unit (a) in the resin and the number of carbon atoms of the alkyl group is 1 performed by 1H-NMR under the following conditions. As the measurement sample, the crystalline vinyl resin fractionated by the above method can be used. Measurement device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.) Measurement frequency: 400 MHz Pulse condition: 5.0 μs Frequency range: 10500 Hz Number of integrations: 64 times Measurement temperature: 30 °C Sample: Put 50 mg of the measurement sample into a sample tube with an inner diameter of 5 mm, add deuterated chloroform (CDCl3) as a solvent, and dissolve it in a constant temperature bath at 40 °C to prepare. The obtained 1Analyze the 1H-NMR chart to identify the structure of each monomer unit. Here, as an example, the measurement of the content ratio of monomer unit (a) and the number of carbon atoms in the alkyl group in the crystalline vinyl resin will be described. The obtained 1 In the 1H-NMR chart, among the peaks attributed to the components of monomer unit (a), select a peak independent of the peaks attributed to the components of other monomer units, and calculate the integral value S1 of this peak. For the other monomer units contained in the crystalline vinyl resin, the integral values are calculated in the same way. For example, when the monomer units constituting the crystalline vinyl resin are monomer unit (a) and one other monomer unit, the content ratio of monomer unit (a) is determined as follows using the above integral value S1 and the integral value S2 of the peak of the other monomer unit. Here, n1 and n2 are the number of hydrogens in the components to which the peaks focused on each site are attributed.

[0078] Content ratio of monomer unit (a) (mol%) = {(S1 / n1) / ((S1 / n1)+(S2 / n2))}×100 Even when there are two or more other monomer units, the content ratio of monomer unit (a) can be calculated in the same way (using S3···Sx, n3···nx). Also, the number of carbon atoms in the alkyl group can be calculated from the integral ratio of the proton peaks in the 1H-NMR chart. When a polymerizable monomer containing no hydrogen atom in the component other than the vinyl group is used, 1 Use 13C-NMR to measure the nuclear as 13C, perform the measurement in the single pulse mode,

[0079] and calculate it in the same way as in 1H-NMR. 13 and measure the nucleus using 13C-NMR as 13 13C and perform the measurement in the single pulse mode, 1 and calculate it in the same way as in 1H-NMR.

[0080] Multiply the ratio (mol%) of each monomer unit calculated by the above method by the molecular weight of each monomer unit to convert the content ratio of each monomer unit to mass%. Thereby, the content ratio (ratio J) of monomer unit (a) based on the mass of the crystalline vinyl resin in the crystalline vinyl resin is calculated. [Content ratio of monomer unit (a) based on the mass of crystalline vinyl resin: ratio J (unit: mass%)] Ratio J = {((S1 / n1) × M1) / (((S1 / n1) × M1) + ((S2 / n2) × M2))} × 100 ··· Equation (7)

[0081] Also, when a unit having an alkyl group with 16 to 30 carbon atoms exists in addition to monomer unit (a), the content ratio (ratio K) of monomer unit (a) in the monomer unit having an alkyl group with 16 to 30 carbon atoms is calculated as follows. For example, when the unit having an alkyl group with 16 to 30 carbon atoms is monomer unit (a) and one other monomer unit, it is calculated by the following formula using the above integration value S1 and the integration value S3 of the peak of the other monomer unit. [Mass ratio of monomer unit (a) in the unit having an alkyl group with 16 to 30 carbon atoms: ratio K (unit: mass%)] Ratio K = {((S1 / n1) × M1) / (((S1 / n1) × M1) + ((S3 / n3) × M3))} × 100 ··· Equation (8) However, M1 and M3 are the molecular weights of each monomer unit. The same method is used for measurement in the amorphous vinyl resin.

[0082] [Calculation method of solubility parameter (SP value)] The SP values (SPa, SPb) of the monomer units are determined as follows according to the calculation method proposed by Fedors. First, the SP values of the monomer units constituting the resin are determined as follows. Here, the monomer unit constituting the resin means the molecular structure in which the double bond of the monomer used when obtaining the resin by polymerization is cleaved by polymerization. For example, when calculating the SP value (σm) (J / cm 3 ) 0.5 of a monomer unit, for the atoms or atomic groups in the molecular structure of the monomer unit, the evaporation energy (Δei) (cal / mol) and molar volume (Δvi) (cm / mol) are obtained from the table described in "polym.Eng.Sci., 14(2), 147 - 154(1974)", and (4.184×ΣΔei / ΣΔvi) 3 is taken as the SP value (J / cm 0.5 ) 3 ) 0.5 and so on.

[0083] <Method for Measuring Acid Value> The acid value is the number of milligrams of potassium hydroxide required to neutralize the acid contained in 1 g of the sample. The acid value of the resin is measured according to JIS K 0070 - 1992. Specifically, it is measured according to the following procedure. (1) Preparation of Reagents Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add ion-exchanged water to make 100 mL, and obtain a phenolphthalein solution. Dissolve 7 g of special grade potassium hydroxide in 5 mL of water, add ethyl alcohol (95% by volume) to make 1 L. Put it in an alkali-resistant container so as not to contact carbon dioxide gas, etc., leave it for 3 days, and then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution is determined from the amount of the potassium hydroxide solution required for neutralization by taking 25 mL of 0.1 mol / L hydrochloric acid in an Erlenmeyer flask, adding several drops of the phenolphthalein solution, and titrating with the potassium hydroxide solution. The 0.1 mol / L hydrochloric acid used is prepared according to JIS K 8001 - 1998.

[0084] (2) Operation (A) This Test Precisely weigh 2.0 g of the sample (for example, crystalline vinyl resin) into a 200 mL Erlenmeyer flask, add 100 mL of a mixed solution of toluene / ethanol (2:1), and dissolve it over 5 hours. Next, add a few drops of the phenolphthalein solution as an indicator and titrate using the potassium hydroxide solution. Note that the end point of the titration is when the faint red color of the indicator persists for 30 seconds. (B) Blank test Perform titration in the same manner as the above operation, except that no sample is used (i.e., only a mixed solution of toluene / ethanol (2:1) is used). (3) Substitute the obtained results into the following formula to calculate the acid value. A = [(C - B) × f × 5.61] / S Here, A: acid value (mgKOH / g), B: added amount of potassium hydroxide solution in the blank test (mL), C: added amount of potassium hydroxide solution in this test (mL), f: factor of the potassium hydroxide solution, S: mass of the sample (g).

Example

[0085] Hereinafter, the present disclosure will be specifically described by way of examples, but these do not limit the present disclosure in any way. In the following formulations, parts are based on mass unless otherwise specified.

[0086] (Preparation of polymerizable monomer (a-1)) Into a pressurized reaction vessel equipped with a stirrer, a temperature control device, a thermometer, an air inlet tube, a pressure reducing device, and a water reducing device, 727.3 parts of cetanol, 174.1 parts of fumaric acid, 2.5 parts of dibutyltin oxide, and 1 part of 2,6-di-tert-butyl-p-cresol were charged and stirred at 120 °C for homogenization. Then, the temperature was raised to 165 °C, and esterification under reduced pressure was carried out while removing the distillate water at 21 kPa for 3 hours. After confirming that the acid value was less than 30 mgKOH / g, esterification under reduced pressure was carried out while removing the distillate water at 3 kPa or less for 12 hours. This was taken out to obtain the polymerizable monomer (a-1).

[0087] (Preparation of polymerizable monomers (a-2) to (a-12)) Polymerizable monomers (a-2) to (a-12) were produced in the same manner as in the preparation example of the polymerizable monomer (a-1), except that the types and addition amounts of the raw materials were changed as shown in Table 1. The compositions of the polymerizable monomers (a-2) to (a-12) are shown in Table 1.

[0088]

Table 1

[0089] (Preparation of Crystalline Vinyl Resin (A-1)) 120.0 parts of xylene and 80.0 parts of polymerizable monomer (a-1) were charged into an autoclave. After heating to 135 °C with stirring under a sealed condition, the pressure was released. Then, the temperature was raised to 155 °C with stirring under a sealed condition. A mixed solution of 14.0 parts of methacrylonitrile, 6.0 parts of styrene, 1.6 parts of di-t-butyl peroxide, and 60.0 parts of xylene was added dropwise over 3 hours while controlling the temperature inside the autoclave to 155 °C to carry out polymerization. After the dropwise addition, the dropping line was washed with 20.0 parts of xylene. After holding at the same temperature for 2.2 hours, it was cooled to 70 °C, and then 12.8 parts of di-t-butyl peroxide was added and reacted. Then, the solvent was removed under reduced pressure of 0.5 - 2.5 kPa at 170 °C for 3 hours to obtain crystalline vinyl resin (A-1). It was confirmed that crystalline vinyl resin (A-1) is a crystalline resin showing a distinct endothermic peak in differential scanning calorimetry (DSC) measurement.

[0090] (Preparation of Crystalline Vinyl Resins (A-2) to (A-23)) Crystalline vinyl resins (A-2) to (A-23) were produced in the same manner as in the production of crystalline vinyl resin (A-1), except that the types and addition amounts of raw materials were changed as shown in Table 2. It was confirmed that crystalline vinyl resins (A-2) to (A-23) are crystalline resins showing distinct endothermic peaks in differential scanning calorimetry (DSC) measurement. The compositions and physical property values of crystalline vinyl resins (A-2) to (A-23) are shown in Table 2.

[0091]

Table 2

[0092] <Example 1> [Manufacture of Toner by Suspension Polymerization] (Manufacture of Toner Particle 1) · n-Butyl acrylate 16.2 parts · Styrene 48.8 parts · Colorant Pigment Blue 15:3 6.5 parts A mixture consisting of the above materials was prepared. The above mixture was put into an attritor (manufactured by Nippon Coke Co., Ltd.), and using zirconia beads with a diameter of 5 mm, it was dispersed at 200 rpm for 2 hours to obtain a raw material dispersion.

[0093] On the other hand, into a container equipped with a high-speed stirring device homomixer (manufactured by Primix Co., Ltd.) and a thermometer, 735.0 parts of ion-exchanged water and 16.0 parts of trisodium phosphate (dodecahydrate) were added, and the temperature was raised to 60°C while stirring at 12000 rpm. Thereto, an aqueous calcium chloride solution in which 9.0 parts of calcium chloride (dihydrate) was dissolved in 65.0 parts of ion-exchanged water was added, and it was stirred at 12000 rpm for 30 minutes while maintaining 60°C. 10% hydrochloric acid was added thereto to adjust the pH to 6.0, and an aqueous medium in which an inorganic dispersion stabilizer containing hydroxyapatite was dispersed in water was obtained.

[0094] Subsequently, the above raw material dispersion was transferred to a container equipped with a stirring device and a thermometer, and the temperature was raised to 60°C while stirring at 100 rpm. · Crystalline vinyl resin (A-1) 35.0 parts · Release agent 1 (DP18) 9.0 parts DP18 (dipentaerythritol stearate wax, melting point 79°C, manufactured by Nisshin Oillio Group, Ltd.) There, after adding the above materials and stirring at 100 rpm for 30 minutes while maintaining the temperature at 60°C, 5.0 parts of t-butyl peroxypivalate (manufactured by NOF Corporation: PERBUTYL PV) as a polymerization initiator was added and stirred for an additional 1 minute. Then, it was poured into an aqueous medium that was being stirred at 12,000 rpm using the above high-speed stirring device. While maintaining the temperature at 60°C, stirring was continued at 12,000 rpm for 20 minutes using the above high-speed stirring device to obtain a granulation liquid.

[0095] The above granulation liquid was transferred to a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 70°C while stirring at 150 rpm under a nitrogen atmosphere. While maintaining the temperature at 70°C, a polymerization reaction was carried out at 150 rpm for 12 hours to obtain a toner particle dispersion liquid. After cooling the obtained toner particle dispersion liquid to 45°C while stirring at 150 rpm, a heat treatment was carried out for 5 hours while maintaining the temperature at 45°C. Then, while maintaining the stirring, dilute hydrochloric acid was added until the pH reached 1.5 to dissolve the dispersion stabilizer. The solid content was filtered off, thoroughly washed with ion-exchanged water, and then vacuum dried at 30°C for 24 hours to obtain toner particles 1.

[0096] (Preparation of Toner 1) To 98.0 parts of the above toner particles 1, 2.0 parts of silica fine particles (hydrophobically treated with hexamethyldisilazane, number average particle diameter of primary particles: 10 nm, BET specific surface area: 170 m 2 / g) was added and mixed at 3000 rpm for 15 minutes using a Henschel mixer (manufactured by Nippon Coke Co., Ltd.) to obtain toner 1. The obtained toner 1 was evaluated by the method shown below. The physical properties of the obtained toner 1 are shown in Table 3, and the evaluation results are shown in Table 4.

[0097]

Table 3

[0098]

Table 4

[0099] <Examples 2 to 37> In Example 1, toner particles 2 to 37 were obtained in the same manner except that the types and amounts of the polymerizable monomers used, the types and amounts of the crosslinking agents, and the amount of the polymerization initiator added were changed as shown in Table 3. Furthermore, external addition similar to that in Example 1 was performed to obtain toners 2 to 37, which were evaluated as Examples 2 to 37. The physical properties of the toners of Examples 2 to 37 are shown in Table 3, and the evaluation results are shown in Table 4.

[0100] <Comparative Examples 1 to 5> In Example 1, comparative toner particles 1 to 5 were obtained in the same manner except that the types and amounts of the polymerizable monomers used, the types and amounts of the crosslinking agents, and the amount of the polymerization initiator added were changed as shown in Table 3. Furthermore, external addition similar to that in Example 1 was performed to obtain comparative toners 38 to 42, which were evaluated as Comparative Examples 1 to 5. The physical properties of the toners of Comparative Examples 1 to 5 are shown in Table 3, and the evaluation results are shown in Table 4. When the obtained toners 2 to 42 were analyzed by the method described above, the values of ratio J and ratio K similar to those in Table 2 were obtained.

[0101] <Toner Evaluation Method> <Evaluation 1> Low-temperature Fixing Property A process cartridge filled with toner was left standing at a temperature of 25°C and a humidity of 40% RH for 48 hours. Using a commercially available Canon printer LBP-712Ci modified to operate even without the fixing unit, an unfixed image of an image pattern in which 9-point square images of 10 mm × 10 mm were evenly arranged over the entire transfer paper was output. The toner loading amount on the transfer paper was 0.80 mg / cm 2 and the fixing start temperature was evaluated. The transfer paper was A4 paper (「Probond paper」: 105 g / m ーbond paper」: 105 g / m 2, (manufactured by Fox River) was used. As the fixing device, an external fixing device was used, which was obtained by removing the fixing device of the LBP-712Ci and modifying it to operate outside the laser beam printer. The external fixing device was used with the fixing temperature increased in 5°C increments from 90°C, and fixing was performed under the condition of a process speed of 240 mm / sec. The fixed image was visually inspected, and the lowest temperature at which no cold offset occurred was set as the fixing start temperature. The evaluation results are shown in Table 4.

[0102] <Evaluation 2> Durability Using a commercially available Canon printer LBP-712Ci, the durability was evaluated. As the evaluation cartridge, the toner contained in a commercially available cartridge was removed, the inside was cleaned with an air blower, and then 200 g of the evaluation toner was filled. The above cartridge was installed in the cyan station, and the evaluation was carried out by installing dummy cartridges for the others. In a normal temperature and normal humidity (N / N) environment (23°C, 60% RH), Canon Oce Red Label (80 g / m 2 ) was used as the transfer paper, and images with a printing rate of 1% were continuously output 20,000 sheets. After the output of the above 20,000 images, one evaluation solid image and one halftone image were output, and the presence or absence of circumferential streaks, so-called development streaks, caused by toner fusion to the regulating member was visually confirmed and evaluated according to the following criteria. The fact that the occurrence of development streaks is suppressed indicates that the toner does not deteriorate even after durable output and that the durability is excellent. The evaluation results are shown in Table 4. [Evaluation Criteria] A: No occurrence of development streaks B: The occurrence of development streaks is 1 or more and 2 or less locations C: The occurrence of development streaks is 3 or more and 4 or less locations D: The occurrence of development streaks is 5 or more locations

[0103] <Evaluation 3> Gloss change of the fixed image after storage [Heat cycle test assuming cargo ship transportation] When the product is transported by sea on a cargo ship, in a situation where temperature and humidity are not controlled, such as in a dry container, depending on the region and situation, it may be exposed to an environment with a large temperature and humidity difference between day and night. Therefore, this condition was set. For the heat cycle test, 100 g of the toner to be evaluated was placed in a 500 ml Sampura (R) poly cup (manufactured by Sampura Tech Co., Ltd.). Next, the poly cup containing the toner was placed in a thermo-hygrostat IX210 (manufactured by Yamato Scientific Co., Ltd.), and a heat cycle test assuming dry container cargo ship transportation was conducted. The specific conditions were as follows: First, it was maintained at a temperature of 30°C and a humidity of 70% RH for 18 hours, then the temperature was changed to 50°C and the humidity to 55% RH over 2 hours and maintained for 2 hours. Next, the temperature was changed to 30°C and the humidity to 70% RH over 2 hours. This heat cycle was repeated 20 times. The above temperature and humidity changes are illustrated in Figure 1.

[0104] 〔Change in Gloss of Fixed Image〕 Before and after the above heat cycle test, the toner was filled into the process cartridge of the above LBP-712Ci and left at a temperature of 25°C and a humidity of 40% RH for 48 hours. Using the LBP-712Ci, an image pattern with 9-point evenly arranged 10 mm × 10 mm square images across the entire transfer paper was output. The toner loading amount on the transfer paper was 0.80 mg / cm 2 The transfer paper used was A4 paper (「Prova Bond Paper」: 105 g / m 2 , manufactured by Fox River). The fixing temperature was set 40°C higher than the fixing start temperature in the low-temperature fixing property evaluation in <1> above. For the output fixed image, the gloss value was measured using a handy gloss meter PG-1 (manufactured by Nippon Denshoku Industries Co., Ltd.). The measurement conditions were set such that the light projection angle and the light reception angle were both 75°, and all 9-point arranged image patterns were measured, and the average value was evaluated. Let the gloss average value of the fixed image before the heat cycle test be G0 and the gloss average value of the fixed image after the heat cycle test be G1. The gloss fluctuation ΔG was calculated using the following formula. ΔG = |G1 - G0| ··· Formula (9) ΔG = |G1―G0| ··· Formula (9)

[0105] The present disclosure relates to the following configuration. (Configuration 1) A toner having toner particles containing a binder resin, wherein the binder resin contains a crystalline vinyl resin and an amorphous vinyl resin, the crystalline vinyl resin contains 5.0 mass% or more of a monomer unit (a) represented by the following formula (1) based on the mass of the crystalline vinyl resin, In TIFF2025094808000010.tif28153 formula (1), R 1 ~R 4 Among them, at least two are each independently -X-COOR 5 and the rest are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X is a single bond or an alkylene group having 1 or 2 carbon atoms, and R 5 is an alkyl group having 16 to 30 carbon atoms, the amorphous vinyl resin contains a tetrahydrofuran-insoluble component, and the toner is characterized by this. (Configuration 2) The toner according to Configuration 1, wherein the binder resin contains 20 to 80 mass% of the crystalline vinyl resin based on the mass of the binder resin. (Configuration 3) The toner according to Configuration 1 or 2, wherein the crystalline vinyl resin contains 30.0 mass% or more of the monomer unit (a) based on the mass of the crystalline vinyl resin. (Configuration 4) In the crystalline vinyl resin, among the monomer units having an alkyl group having 16 to 30 carbon atoms including the monomer unit (a), the content ratio of the monomer unit (a) is 50.0 to 100.0 mass%, and the toner according to any one of Configurations 1 to 3. (Configuration 5) The toner according to any one of Configurations 1 to 4, wherein the acid value of the crystalline vinyl resin is 3.0 mgKOH / g or less. (Configuration 6) The crystalline vinyl resin contains, in addition to the monomer unit (a), a monomer unit (b) different from the monomer unit (a), Let the SP value of the monomer unit (a) be SPa (J / cm 3 ) 0.5 and the SP value of the monomer unit (b) be SPb (J / cm 3 ) 0.5 . When the toner according to any one of Configurations 1 to 5, wherein SPa and SPb satisfy the following formula (2). 3.0 ≦ (SPb - SPa) ≦ 21.0 ··· Formula (2) (Configuration 7) The toner according to any one of Configurations 1 to 6, wherein the binder resin contains 2.0 to 50.0% by mass of the tetrahydrofuran-insoluble content based on the mass of the binder resin. (Configuration 8) The toner according to any one of Configurations 1 to 7, wherein the crystalline vinyl resin contains 5.0 to 100.0% by mass of the tetrahydro furan-insoluble content based on the mass of the crystalline vinyl resin. (Configuration 9) The amorphous vinyl resin is a polymer of a composition containing a polymerizable monomer and a crosslinking agent, and the toner according to any one of Configurations 1 to 8, wherein the crosslinking agent has two or more polymerizable double bonds.

Claims

1. A toner having toner particles containing a binder resin, wherein the binder resin contains a crystalline vinyl resin and an amorphous vinyl resin, the crystalline vinyl resin contains 5.0% by mass or more of a monomer unit (a) represented by the following formula (1) based on the mass of the crystalline vinyl resin, 【Chemical 1】 In formula (1), R １ ~R ４ Among them, at least two are each independently -X-COOR ５ , and the rest are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X is a single bond, or an alkylene group having 1 or 2 carbon atoms, and R ５ is an alkyl group having 16 to 30 carbon atoms, the amorphous vinyl resin contains a tetrahydrofuran-insoluble component, and the toner is characterized by this.

2. The toner according to claim 1, wherein the binder resin contains 20 to 80% by mass of the crystalline vinyl resin based on the mass of the binder resin.

3. The toner according to claim 1 or 2, wherein the crystalline vinyl resin contains 30.0% by mass or more of the monomer unit (a) based on the mass of the crystalline vinyl resin.

4. In the crystalline vinyl resin, among the monomer units having an alkyl group with 16 to 30 carbon atoms including the monomer unit (a), the content ratio of the monomer unit (a) is 50.0 to 100.0% by mass. The toner according to claim 1 or 2.

5. The toner according to claim 1 or 2, wherein the acid value of the crystalline vinyl resin is 3.0 mgKOH / g or less.

6. The crystalline vinyl resin contains, in addition to the monomer unit (a), a monomer unit (b) different from the monomer unit (a), Let the SP value of the monomer unit (a) be SPa (J / cm ３ ), ０．５ and let the SP value of the monomer unit (b) be SPb (J / cm ３ ). ０．５ When this is the case, and the toner according to claim 1 or 2, wherein the SPa and the SPb satisfy the following formula (2). 3.0 ≤ (SPb - SPa) ≤ 21.0... Formula (2)

7. The toner according to claim 1 or 2, wherein the binder resin contains 2.0 to 50.0% by mass of the tetrahydrofuran-insoluble component based on the mass of the binder resin.

8. The toner according to claim 1 or 2, wherein the crystalline vinyl resin contains 5.0 to 100.0% by mass of the tetrahydrofuran-insoluble component based on the mass of the crystalline vinyl resin.

9. The amorphous vinyl resin is a polymer of a composition containing a polymerizable monomer and a crosslinking agent, and the toner according to claim 1 or 2, wherein the crosslinking agent has two or more polymerizable double bonds.

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