Toner

Abstract

To provide a toner that contains pigment dispersed in toner particles including a large amount of crystalline resin, that is, a toner excellent in low temperature fixability and tinting power.SOLUTION: A toner has toner particles containing a binder resin, pigment, and pigment dispersant. The binder resin contains a crystalline resin in an amount of 20.0 mass% or more and 100.0 mass% or less. The pigment dispersant has a polymer part containing a specific structure interacting with the pigment, and a specific monomer unit interacting with the crystalline resin. The content of the specific structure interacting with the pigment in the pigment dispersant is 1.0 mass% or more and 15.0 mass% or less. The content of the specific monomer unit interacting with the crystalline resin in the pigment dispersant is 45.0 mass% or more and 80.0 mass% or less. The weight average molecular weight (Mw) of the pigment dispersant is 10000 or more and 50000 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a toner used for forming a toner image by developing an electrostatic latent image formed by a method such as electrophotography, electrostatic recording, or toner jet recording. [Background technology]

[0002] In the past, energy saving has been considered a major technical issue in electrophotographic devices, and a significant reduction in the amount of heat required for fixing devices has been considered. In particular, there is a growing need for toners that can be fixed with less energy, that is, with so-called "low-temperature fixability." As a method for enabling fixing at low temperatures, a method of using a crystalline resin as a binder resin has been considered. Crystalline resins have the property that they hardly soften at temperatures lower than their melting point because their molecular chains are regularly arranged. Furthermore, when the melting point is exceeded, the crystals melt suddenly, which is accompanied by a rapid drop in viscosity. For this reason, they are attracting attention as a material that has excellent sharp melting properties and low-temperature fixing properties. Patent Document 1 proposes a toner characterized in that a sea-island structure consisting of a sea part mainly made of a crystalline resin and an island part mainly made of an amorphous resin is observed in a cross-sectional observation of a toner particle. The toner described in Patent Document 1 can be fixed with low energy. However, it has a problem that the crystalline part adversely affects the dispersion of a colorant such as a pigment, and the coloring power is likely to decrease. On the other hand, Patent Document 2 proposes a toner in which the relationship between the hydrophobicity parameters of the crystalline polyester and the pigment dispersant is specified in toner particles containing a binder resin, a crystalline polyester, and a pigment dispersant. The toner described in Patent Document 2 achieves both low-temperature fixability and coloring power. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-142632 A [Patent Document 2] JP 2016-157104 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a system in which a large amount of crystalline resin is introduced into the binder resin for further energy saving, the effect is limited and coloring power cannot be improved even if the pigment dispersant disclosed in Patent Document 2 is used. There is still a need to improve the low-temperature fixing property and coloring power of the toner. The present disclosure provides a toner in which a pigment is dispersed in toner particles containing a large amount of a crystalline resin, that is, a toner having excellent low-temperature fixing properties and coloring power. [Means for solving the problem]

[0005] The present invention provides a toner having toner particles containing a binder resin, a pigment, and a pigment dispersant, The binder resin contains a crystalline resin in an amount of 20.0% by mass or more and 100.0% by mass or less, The pigment dispersant has a structure represented by the following formula (1) and a polymer moiety containing a monomer unit represented by the following formula (3), The content of the structure represented by the following formula (1) in the pigment dispersant is 1.0 mass % or more and 15.0 mass % or less, The content of the monomer unit represented by the following formula (3) in the pigment dispersant is 45.0 mass % or more and 80.0 mass % or less, The toner is characterized in that the weight average molecular weight (Mw) of the pigment dispersant is 10,000 or more and 50,000 or less.

[0006] [ka] (In formula (1), R1 represents an alkyl group having a substituent, an alkyl group having no substituent, a phenyl group having a substituent, or an unsubstituted phenyl group; R2~R 11at least one of the groups is a linking group to the polymer moiety or a moiety that is bonded to the polymer moiety via a single bond, R2 to R which are not linking groups 11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a cyano group, a trifluoromethyl group, a carboxyl group, or a group represented by the following formula (2-1), or R to R 11 The adjacent groups are represented by the following formula (2-2):

[0007] [ka] (In formula (2-1), * denotes R2 to R6 or R7 to R 11 represents the bonding position to the aromatic ring having the formula: R 12 represents a hydrogen atom, a substituted or unsubstituted alkyl group, an aralkyl group, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group. A1 is an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13 represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group.

[0008] [ka] (In formula (2-2), * and ** represent R2 to R6 or R7 to R 11 represents the bonding position to the aromatic ring having the formula: The group represented by formula (2-2) is R2 to R6 or R7 to R 11 By bonding to an aromatic ring having the formula: A2 is an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group.

[0009] [ka] (In formula (3), R 14 represents a hydrogen atom or a methyl group, L1 represents an ester bond or an amide bond; m represents an integer between 20 and 30. Effect of the Invention

[0010] According to the present invention, a toner having excellent low-temperature fixing property and coloring power can be obtained. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The expressions "XX or more and YY or less" or "XX to YY" representing a numerical range mean a numerical range including the endpoints, that is, the lower limit and the upper limit, unless otherwise specified.

[0012] [Features of the present invention] The present invention provides a toner having toner particles containing a binder resin, a pigment, and a pigment dispersant, (i) the binder resin contains a crystalline resin in an amount of 20.0% by mass or more and 100.0% by mass or less; (ii) the pigment dispersant has a structure represented by the following formula (1) and a polymer moiety containing a monomer unit represented by the following formula (3), the content of the structure represented by the following formula (1) in the pigment dispersant being 1.0% by mass or more and 15.0% by mass or less, and the content of the monomer unit represented by the following formula (3) being 45.0% by mass or more and 80.0% by mass or less;

[0013] [ka] (In formula (1), R1 represents an alkyl group having a substituent, an alkyl group having no substituent, a phenyl group having a substituent, or an unsubstituted phenyl group; R2~R 11 at least one of the groups is a linking group to the polymer moiety or a moiety that is bonded to the polymer moiety via a single bond, R2 to R which are not linking groups 11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a cyano group, a trifluoromethyl group, a carboxyl group, or a group represented by the following formula (2-1), or R to R 11 The adjacent groups are represented by the following formula (2-2):

[0014] [ka] (In formula (2-1), * denotes R2 to R6 or R7 to R 11 represents the bonding position to the aromatic ring having the formula: R 12 represents a hydrogen atom, a substituted or unsubstituted alkyl group, an aralkyl group, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group. A1 is an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13 represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group.

[0015] [ka] (In formula (2-2), * and ** represent R2 to R6 or R7 to R 11 represents the bonding position to the aromatic ring having the formula: The group represented by formula (2-2) is R2 to R6 or R7 to R 11 By bonding to an aromatic ring having the formula: A2 is an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13 represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group.

[0016] [ka] (In formula (3), R 14 represents a hydrogen atom or a methyl group, L1 represents an ester bond or an amide bond; m represents an integer between 20 and 30.

[0017] (iii) Furthermore, the weight average molecular weight (Mw) of the pigment dispersant is 10,000 or more and 50,000 or less. The present invention is characterized by the following:

[0018] Each of the above requirements will be explained in detail below.

[0019] The toner of the present invention has toner particles containing a binder resin containing 20.0% by mass or more and 100.0% by mass or less of a crystalline resin, a pigment, and a pigment dispersant.

[0020] The pigment dispersant has a structure represented by the above formula (1) and a polymer moiety containing the monomer unit represented by the above formula (3).

[0021] In addition, the content of the structure represented by the above formula (1) in the pigment dispersant is 1.0 mass % or more and 15.0 mass % or less, and the content of the monomer unit represented by the above formula (3) is 45.0 mass % or more and 80.0 mass % or less.

[0022] Furthermore, it is an essential requirement that the weight average molecular weight (Mw) of the pigment dispersant be 10,000 or more and 50,000 or less.

[0023] It has been found that by satisfying the above conditions, a toner having excellent low-temperature fixing ability and coloring power can be obtained. The present inventors consider the detailed mechanism as follows.

[0024] When dispersing a pigment in a binder resin containing 20.0% by mass or more of crystalline resin, it is necessary to carefully consider the interaction between the binder resin and the pigment dispersant when designing. Specifically, it is necessary to use a pigment dispersant that has a "site that interacts with the pigment" represented by formula (1) and a "site that interacts with the crystalline resin" that contains a monomer unit represented by formula (3).

[0025] Furthermore, the content of the structure represented by formula (1) in the pigment dispersant must be 1.0% by mass or more and 15.0% by mass or less, and the content of the monomer unit represented by formula (3) must be 45.0% by mass or more and 80.0% by mass or less. By setting the content within these ranges, a balance can be achieved between the interaction between the pigment and the pigment dispersant and the interaction between the pigment dispersant and the crystalline resin.

[0026] Here, the structure represented by formula (1) exhibits strong π-π interaction and has strong hydrogen bonding properties, and therefore easily interacts with the functional groups of the pigment. The inclusion of a specified amount of formula (1) enables the pigment dispersant to be present near the pigment. On the other hand, the inclusion of a specified amount of the monomer unit represented by formula (3) increases the affinity with the crystalline resin, and even in a binder resin containing 20.0 mass% or more of crystalline resin, the polymer chain of the polymer moiety derived from formula (3) can spread in the binder resin. The spread polymer chain then exhibits steric hindrance and suppresses the aggregation of the pigments, thereby obtaining a toner with excellent low-temperature fixing property and coloring power, which is the effect of the present invention.

[0027] If the content of the structure represented by formula (1) is less than 1.0% by mass, the amount of interaction with the pigment is small, so that it cannot be present near the pigment, and the effect of the present invention cannot be obtained. If it is more than 15.0% by mass, the proportion of the structure represented by formula (1) in the pigment dispersant becomes too high, so that the polymer chain (also called loop length) of the polymer portion between the structures represented by formula (1) and the structures represented by formula (1) is insufficient, and therefore steric hindrance to suppress aggregation of the pigments is not obtained. As a result, the coloring power is reduced.

[0028] If the content of the monomer unit represented by formula (3) is less than 45.0% by mass, in a binder resin containing 20% ​​or more of crystalline resin, the affinity to the binder resin is low, the polymer portion shrinks, and steric hindrance to suppress the aggregation of pigments is not obtained. As a result, the coloring power is reduced. In addition, the melting point of the pigment dispersant is reduced, resulting in poor heat-resistant storage stability. If the content of the monomer unit represented by formula (3) is more than 80.0% by mass, the affinity to the crystalline resin becomes too high, and the monomer unit is taken up by the binder resin and cannot be present near the pigment. As a result, the coloring power is reduced.

[0029] If the weight average molecular weight (Mw) of the pigment dispersant is less than 10,000, steric hindrance is not obtained, and therefore the aggregation of pigments cannot be suppressed. As a result, the coloring power is reduced. In addition, since the crystallinity derived from the side chain of the polymer portion is not obtained, when the toner is made, the toner becomes a low melting point component, and the heat resistance and storage stability are poor. If it is greater than 50,000, the intermolecular interaction between the side chain of the polymer portion and the crystalline resin in the binder resin increases. As a result, the interaction between the structure represented by the above formula (1) and the pigment becomes greater than that between the pigment, and the pigment dispersant is removed from the pigment and taken up by the crystalline resin in the binder resin. As a result, the effect of the present invention is not obtained and the coloring power is reduced. In order for the pigment dispersant of the present invention to be effective in a binder resin containing a large amount of crystalline resin, the balance between the content of the structure represented by formula (1) and formula (3) in the pigment dispersant and its molecular weight is important.

[0030] [Components of toner] <The structure of pigment dispersant represented by formula (1)> The structure of the pigment dispersant represented by formula (1) will now be described in detail.

[0031] Examples of the alkyl group in R1 in formula (1) include linear, branched, or cyclic alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and a cyclohexyl group.

[0032] The alkyl group or phenyl group of R1 in the above formula (1) may be further substituted with a substituent, so long as it does not significantly impair the affinity to the pigment. In this case, the substituent that may be substituted includes, for example, a halogen atom, a nitro group, an amino group, a hydroxyl group, a cyano group, and a trifluoromethyl group.

[0033] Of the above, R1 in the above formula (1) is preferably a methyl group from the viewpoint of affinity to the pigment.

[0034] From the viewpoint of affinity to the pigment, it is preferable that at least one of R2 to R6 in the above formula (1) is a linking group that constitutes a bond with the polymer moiety.

[0035] R2 to R6 that are not linking groups each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a cyano group, a trifluoromethyl group, a carboxyl group, a group represented by the above formula (2-1), or a group represented by the above formula (2-2).

[0036] It is more preferable that R2 to R6 that are not linking groups are all hydrogen atoms.

[0037] R7 to R 11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a cyano group, a trifluoromethyl group, a carboxyl group, a group represented by the above formula (2-1) or a group represented by the above formula (2-2).

[0038] Among them, from the viewpoint of affinity with pigments, R7 to R 11 At least one of R7 to R8 is preferably a group represented by the above formula (2-1) or formula (2-2). 11 However, it is preferable that each of them is a hydrogen atom. An example of a structure that satisfies this requirement is shown in the following formula (4).

[0039] [ka] (In formula (4), R 15 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted phenyl group. R 16 ~R 20 At least one of the groups is a linking group that constitutes a bond with the polymer portion. R that is not a linking group 16 ~R 20 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an amino group, a cyano group, a trifluoromethyl group, or a carboxy group.

[0040] R in the above formula (2-1) 12 Examples of the alkyl group in the formula (I) include linear, branched, or cyclic alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and a cyclohexyl group.

[0041] R in the above formula (2-1) 12 Examples of the aralkyl group in the formula (I) include a benzyl group and a phenethyl group.

[0042] R in the above formula (2-1) 12Examples of the alkyloxycarbonyl group (-C(=O)-OAlkyl) in the above formula include a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group, a tert-butoxycarbonyl group, an n-pentyloxycarbonyl group, and an n-hexyloxycarbonyl group.

[0043] R in the above formula (2-1) 12 Examples of the aralkyloxycarbonyl group (-C(=O)-O-Ararkyl) in the above formula include a benzyloxycarbonyl group and a phenethyloxycarbonyl group.

[0044] Among the above, from the viewpoint of affinity with pigments, R 12 is preferably a hydrogen atom, a methyl group, or an ethyl group.

[0045] A1 in the above formula (2-1) and A2 in the above formula (2-2) each represent an oxygen atom, a sulfur atom, or NR 13 R 13 is preferably a hydrogen atom, a tert-butoxycarbonyl group, or a benzyloxycarbonyl group. Among these, from the viewpoint of affinity to the pigment, A1 and A2 are more preferably an oxygen atom.

[0046] The linking group for linking the structure represented by the above formula (1) with the polymer portion is not particularly limited as long as it is a divalent linking group. For example, an ester bond (-COO-), a thioester bond (-COS-), or a carboxylic acid amide bond (-CONH-) can be mentioned. Among them, an ester bond or a carboxylic acid amide bond is preferable.

[0047] Specifically, the linking group is particularly preferably one represented by the following formula (L1) or (L2).

[0048] [ka] [In formulae (L1) and (L2), * represents a bonding site to a carbon atom in the polymer portion, and ** represents a bonding site to a carbon atom in an aromatic ring having a structure represented by formula (1)]

[0049] When the polymer moiety is bonded to the structure represented by formula (1) or formula (4) via a functional group such as a carboxylate bond (-COO-) derived from the polymer moiety, the bond including the functional group is referred to as a linking group.

[0050] <Polymer moiety of pigment dispersant> Next, the polymer portion will be described in detail.

[0051] The polymer portion must contain a predetermined amount of the monomer unit represented by the above formula (3), and specific examples of the monomer constituting the monomer unit represented by formula (3) include behenyl acrylate, behenyl methacrylate, octacosane acrylate, octacosane methacrylate, triacontane acrylate, and triacontane methacrylate. Among these, behenyl acrylate and behenyl methacrylate are preferred.

[0052] The polymer segment preferably contains components derived from the following monomers in addition to the monomer unit represented by the above formula (3).

[0053] Monomers include styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, and styrene derivatives such as p-phenylstyrene; acrylic polymerizable monomers such as acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, n-lauryl acrylate, cyclohexyl acrylate, 2-methoxyethyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and 2-benzoyloxyethyl acrylate; Methacrylic polymerizable monomers such as methacrylic acid, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, 2-methoxyethyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate;

[0054] The polymer moiety can be produced by any of the polymerization methods of solution polymerization, suspension polymerization, emulsion polymerization, dispersion polymerization, precipitation polymerization, and bulk polymerization. Although not particularly limited, solution polymerization in a solvent capable of dissolving each component used during production is preferred. Specifically, the solvent can be a polar organic solvent such as alcohols such as methanol, ethanol, and 2-propanol, ketones such as acetone and methyl ethyl ketone, ethers such as tetrahydrofuran and diethyl ether, ethylene glycol monoalkyl ethers or acetates thereof, propylene glycol monoalkyl ethers or acetates thereof, and diethylene glycol monoalkyl ethers, or a non-polar solvent such as toluene and xylene, either alone or in combination.

[0055] As shown in the following formula, the polymer segment is composed of X corresponding to the monomer unit represented by formula (3), Z linked to formula (1), and Y corresponding to other monomer units as required, randomly arranged.

[0056] [ka] [In the above structural formula, X is a monomer unit represented by formula (3), Z is a monomer unit linked to formula (1), Y1 to Ym are other monomer units, and "co" is a symbol indicating that the arrangement of each monomer unit constituting the copolymer is disordered.]

[0057] The pigment dispersant preferably has a melting point peak derived from the polymer moiety at 50° C. or more and 70° C. or less in DSC measurement. By having a melting point peak at 50° C. or more and 70° C. or less, the dispersant has excellent resistance to thermal deformation and good storage stability. The melting point peak can be adjusted by the content of the monomer unit represented by formula (3) and the type and content of other monomers.

[0058] <Crystalline resin> Examples of the crystalline resin include vinyl resins, polyester resins, polyurethane resins, and epoxy resins having crystallinity. Among them, vinyl resins or polyester resins having crystallinity are preferred. Vinyl resins having crystallinity are more preferred.

[0059] In the case of a crystalline vinyl resin, it is preferable that the resin contains a unit represented by formula (5).

[0060] [ka] (In formula (5), R 21 represents a hydrogen atom or a methyl group, L2 represents a single bond, an ester bond, or an amide bond; n represents an integer between 15 and 30.

[0061] By having the unit represented by formula (5), it becomes easy to form a side chain crystal structure, so that sharp melting property can be obtained and low temperature fixability can be further improved. n in formula (5) is preferably 17 or more and 29 or less, more preferably 19 or more and 23 or less.

[0062] It is possible to have other units in addition to the unit represented by formula (5). As a method for introducing other units, there is a method of copolymerizing with other polymerizable monomers.

[0063] Other polymerizable monomers include the following:

[0064] Monomers include styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, and styrene derivatives such as p-phenylstyrene; acrylic polymerizable monomers such as acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, n-lauryl acrylate, cyclohexyl acrylate, 2-methoxyethyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and 2-benzoyloxyethyl acrylate, and acrylonitrile; Methacrylic polymerizable monomers such as methacrylic acid, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, 2-methoxyethyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate, and methacrylonitrile.

[0065] Of these, it is preferable to use styrene, methacrylic acid, acrylic acid, acrylonitrile, and methacrylonitrile.

[0066] It is preferable that the polarity parameter P1 of the pigment dispersant and the polarity parameter P2 of the crystalline resin satisfy the following formula. │P1-P2│≦0.10 (P1 indicates the volume fraction of acetonitrile at the precipitation point of the pigment dispersant, which is determined by adding 0.10 parts by mass of acetonitrile to a solution consisting of 0.05 parts by mass of the pigment dispersant and 1.48 parts by mass of chloroform. P2 indicates the volume fraction of acetonitrile at the precipitation point of the crystalline resin when 0.10 parts by mass of acetonitrile is added to a solution consisting of 0.05 parts by mass of the crystalline resin and 1.48 parts by mass of chloroform.

[0067] The closer the polarity parameter values ​​of the pigment dispersant and the crystalline resin are, the higher the affinity is, which is preferable. P1 can be controlled by changing the composition of the polymer portion of the pigment dispersant. P2 can be controlled by changing the composition of the crystalline resin. Details of the method for measuring the crystallinity parameters will be described later.

[0068] <Other binder resins> The binder resin preferably contains an amorphous resin, and when the cross section of the toner particle is observed by a scanning transmission electron microscope, the cross section has a matrix-domain structure, the matrix preferably contains a crystalline resin as a main component, and the domain preferably contains an amorphous resin as a main component, and the toner particle has excellent durability and hot offset resistance. Examples of the amorphous resin include vinyl resin, polyester resin, polyurethane resin, and epoxy resin. Among them, vinyl resin is preferable.

[0069] Although the inclusion of a crystalline resin as the main component in the matrix provides the above-mentioned excellent properties, the crystalline resin in the matrix affects pigment dispersion and is prone to cause a decrease in coloring power. However, by using the pigment dispersant of the present invention, it becomes possible to disperse the pigment without being affected by the crystalline resin in the matrix, and high coloring power can be obtained.

[0070] <Pigments> The pigment preferably includes a pigment selected from the following group:

[0071] Carbon black; CI Pigment Yellow 74, 93, 139, 155, 180, 185; CI Pigment Red 31, 122, 150, 170, 185, 258, 269; CI Pigment Blue 15:3, 15:4

[0072] In the case of a pigment selected from the above group, adsorption due to π-π interactions or hydrogen bonding is stronger, so that the pigment dispersant is more likely to be present near the pigment, and pigment dispersibility is more likely to be improved.

[0073] More preferred are carbon black; CI Pigment Yellow 155, 180, 185; CI Pigment Red 122, 150; and CI Pigment Blue 15:3.

[0074] The content of the pigment dispersant relative to the pigment is preferably 1.0 parts by mass or more and 20.0 parts by mass or less, and more preferably 3.0 parts by mass or more and 15.0 parts by mass or less, relative to 100 parts by mass of the pigment.

[0075] <Wax> As the wax, it is preferable to use a wax having a number average molecular weight (Mn) of 300 to 3000 inclusive, since this makes it easier to ensure releasability. There are no particular limitations on the type of wax, but it is preferable to use a hydrocarbon wax or an ester wax.

[0076] Examples of hydrocarbon waxes include the following:

[0077] Aliphatic hydrocarbon waxes: low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymers, Fischer-Tropsch wax, or waxes obtained by oxidizing or adding acids to these.

[0078] The ester wax may be any wax having at least one ester bond in one molecule, and may be either a natural ester wax or a synthetic ester wax.

[0079] The ester wax is not particularly limited, but examples thereof include the following.

[0080] Esters of monohydric alcohols and monocarboxylic acids, such as behenyl behenate, stearyl stearate, and palmityl palmitate; Esters of divalent carboxylic acids and monoalcohols, 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 hexahydric alcohols and monocarboxylic acids, such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabehenate; Esters of polyfunctional alcohols and monocarboxylic acids, such as polyglycerin behenate; natural ester waxes, such as carnauba wax and rice wax; Among these, esters of hexahydric alcohols and monocarboxylic acids such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, dipentaerythritol hexabehenate, etc. are preferred. They interact with the pigment dispersant of the present invention, reducing the domain size of the wax, eliminating the uneven distribution of the pigment in the toner particles, and further improving the coloring power and color gamut.

[0081] <Method of manufacturing toner particles> The toner particles according to the present invention may be produced by any method, but it is preferable to produce the toner particles by a method for producing toner particles in which a polymerizable monomer composition is granulated in an aqueous medium, such as a suspension polymerization method, an emulsion polymerization method, or a suspension granulation method.

[0082] A method for producing toner particles will be described below using the suspension polymerization method, which is the most suitable method for producing toner particles used in the present invention.

[0083] The above-mentioned pigment dispersant, pigment, crystalline resin, wax, polymerizable monomer for forming binder resin, and other additives as required are uniformly dissolved or dispersed by a dispersing machine such as a homogenizer, ball mill, colloid mill, ultrasonic dispersing machine, and a polymerization initiator is dissolved therein to prepare a polymerizable monomer composition. The polymerizable monomer composition is then suspended in an aqueous medium containing a dispersion stabilizer and polymerized to produce toner particles.

[0084] The polymerizable monomer may be, as a monofunctional polymerizable monomer, styrene derivatives such as styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, and p-phenylstyrene; acrylic polymerizable monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and 2-benzoyloxyethyl acrylate; Methacrylic polymerizable monomers such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate.

[0085] Examples of the polyfunctional polymerizable monomer include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2'-bis(4-(acryloxydiethoxy)phenyl)propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol diacrylate, ethylene glycol dimeth ... Examples of suitable vinyl ethers include ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis(4-(methacryloxydiethoxy)phenyl)propane, 2,2'-bis(4-(methacryloxypolyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.

[0086] Monofunctional polymerizable monomers can be used alone or in combination of two or more kinds, monofunctional polymerizable monomers can be used in combination with polyfunctional polymerizable monomers, or polyfunctional polymerizable monomers can be used alone or in combination of two or more kinds.

[0087] The polymerization initiator may be added simultaneously with the addition of other additives to the polymerizable monomer, or may be mixed immediately before suspending in an aqueous medium. Also, the polymerization initiator may be added in the form of a solution in the polymerizable monomer or a solvent immediately after granulation and before starting the polymerization reaction.

[0088] The pigment is preferably used in an amount of 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin.

[0089] The polymerization initiator may be an organic peroxide initiator or an azo polymerization initiator. The organic peroxide initiator may be the following: benzoyl peroxide, lauroyl peroxide, di-α-cumyl peroxide, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, bis(4-t-butylcyclohexyl)peroxydicarbonate, 1,1-bis(t-butylperoxy)cyclododecane, t-butylperoxymaleic acid, bis(t-butylperoxy)isophthalate, methyl ethyl ketone peroxide, tert-butylperoxy-2-ethylhexanoate, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and tert-butylperoxypivalate.

[0090] Examples of the azo polymerization initiator include 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobismethylbutyronitrile.

[0091] Also, a redox initiator that combines an oxidizing substance and a reducing substance can be used as the polymerization initiator. Examples of the oxidizing substance include hydrogen peroxide, inorganic peroxides such as persulfates (sodium salts, potassium salts, and ammonium salts), and oxidizing metal salts such as tetravalent cerium salts. Examples of the reducing substance include reducing metal salts (divalent iron salts, monovalent copper salts, and trivalent chromium salts), ammonia, lower amines (amines having about 1 to 6 carbon atoms such as methylamine and ethylamine), amino compounds such as hydroxylamine, reducing sulfur compounds such as sodium thiosulfate, sodium hydrosulfite, sodium hydrogensulfite, sodium sulfite, and sodium formaldehyde sulfoxylate, lower alcohols (having 1 to 6 carbon atoms), ascorbic acid or its salts, and lower aldehydes (having 1 to 6 carbon atoms).

[0092] The polymerization initiator is selected with reference to its 10-hour half-life temperature and is used alone or in combination. The amount of the polymerization initiator to be added varies depending on the desired degree of polymerization, but is generally 0.5 parts by mass or more and 20.0 parts by mass or less per 100.0 parts by mass of the polymerizable monomer.

[0093] In order to control the degree of polymerization, a known chain transfer agent and a polymerization inhibitor may be further added.

[0094] The dispersion stabilizer used when preparing the aqueous medium may be a known inorganic dispersion stabilizer or an organic dispersion stabilizer. Examples of inorganic dispersion stabilizers include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina. On the other hand, examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salts, and starch. The amount of these dispersion stabilizers used is preferably 0.2 parts by mass or more and 20.0 parts by mass or less relative to 100.0 parts by mass of the polymerizable monomer.

[0095] Among these dispersion stabilizers, when a dispersion stabilizer of an inorganic compound is used, a commercially available one may be used as it is, but in order to obtain a dispersion stabilizer with a finer particle size, the inorganic compound may be produced in an aqueous medium. For example, in the case of tricalcium phosphate, it can be obtained by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high agitation.

[0096] In the present invention, in order to improve image quality, it is preferable that an external additive is added to the toner particles. As the external additive, an inorganic fine powder such as silica fine powder, titanium oxide fine powder, or aluminum oxide fine powder is preferably used.

[0097] These inorganic fine powders are preferably subjected to a hydrophobizing treatment with a hydrophobizing agent such as a silane coupling agent, silicone oil or a mixture thereof.

[0098] Furthermore, in the toner of the present invention, external additives other than those mentioned above may be mixed into the toner particles, if necessary.

[0099] The total amount of inorganic fine powder added is preferably 1.0 part by mass or more and 5.0 parts by mass or less with respect to 100.0 parts by mass of toner particles (toner particles before addition of external additives).

[0100] [Methods for measuring various physical properties] The methods for measuring various physical properties according to the present invention will be described below.

[0101] <Composition analysis method> The structure of the pigment dispersant and the crystalline resin were determined using the following equipment. 13 C-NMR: FT-NMR AVANCE-600 manufactured by Bruker Biospin (solvent used: deuterated chloroform) In addition, 13 C-NMR was quantified and compositional analysis was performed using the inverse gated decoupling method with chromium(III) acetylacetonate as a relaxation reagent.

[0102] The molar composition ratios of each monomer unit of the pigment dispersant and the crystalline resin were calculated by the above measurements, and then the mass composition ratios were calculated from the molecular weights of each monomer unit.

[0103] <Method of measuring molecular weight> The weight average molecular weight (Mw) of the toner and the pigment dispersant is measured by gel permeation chromatography (GPC) as follows.

[0104] A sample is dissolved in tetrahydrofuran (THF) at room temperature. The resulting solution is then filtered through a solvent-resistant membrane filter "Myshoridisc" (manufactured by Tosoh Corporation) with a pore size of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of components soluble in THF is 0.8 mass%. This sample solution is used to perform measurements under the following conditions. Equipment: High-speed GPC equipment "HLC-8220GPC" [Tosoh Corporation] Column: 2 columns of LF-604 [Showa Denko Co., Ltd.] Eluent:THF Flow rate: 0.6mL / min Oven temperature: 40℃ Sample injection volume: 0.020mL The molecular weight of the sample was calculated using a molecular weight calibration curve prepared using standard polystyrene resins (e.g., 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). Use.

[0105] <Measuring method for polarity parameters P1 and P2> The polarity parameter P1 in the present invention was measured by the following method.

[0106] Put 50 mg (0.05 g) of pigment dispersant into an 8 ml sample bottle, dissolve it in 1.48 g of chloroform, and measure the initial mass (W1). Place a stir bar in the sample bottle, and while stirring with a magnetic stirrer, (a) drop 100 mg (0.1 g) of acetonitrile and continue stirring for 20 seconds. (b) Visually check to see if it has become cloudy. If it has not become cloudy, repeat steps (a) and (b). Stop the operation at the point where cloudiness is confirmed (precipitation point) and measure the mass (W2). All measurements are performed at 25°C and normal pressure.

[0107] Calculate P1 according to the following formula: Initial mass before adding acetonitrile W1(g) Mass W2 (g) at the cloudy point after adding acetonitrile Polarity Parameter = {(W2-W1) / 0.78} / {((W2-W1) / 0.78)+1}

[0108] P2 is also measured in the same manner as above, except that the pigment dispersant is replaced with a crystalline resin.

[0109] <Melt point measurement method> The melting points of the pigment dispersant and the like are measured using a differential scanning calorimeter "Q1000" (manufactured by TA Instruments) in accordance with ASTM D3418-82.

[0110] The melting points of indium and zinc are used to correct the temperature of the detector, and the heat quantity is corrected using the heat of fusion of indium.

[0111] Specifically, 5 mg of sample is weighed out and placed in an aluminum pan, and an empty aluminum pan is used as a reference. Measurements are performed at a temperature range of 0°C to 150°C at a heating rate of 10°C / min. In the measurement, the temperature is raised to 150°C once, then lowered to 0°C, and then raised again. The peak temperature of the maximum endothermic peak on the DSC curve in the temperature range of 0°C to 150°C during this second heating process is taken as the melting point.

[0112] <Observation of matrix domain structure in toner cross section> The state of the matrix domain structure (sea-island structure) in the cross section of the toner is confirmed by observing the cross section of the toner using a scanning transmission electron microscope. The cross section of the toner is observed after ruthenium staining. That is, the cross section image of the toner is a cross section image of a toner stained with ruthenium, and the observation procedure for the cross section of the toner is as follows.

[0113] The toner is embedded in a visible light curable resin (D-800, manufactured by Nissin EM Co., Ltd.) so as to be as dispersed as possible, and cut to a thickness of 100 nm using an ultrasonic ultramicrotome (UC7, manufactured by Leica Co., Ltd.).

[0114] The obtained thin sample is stained for 15 minutes in a 500 Pa RuO4 gas atmosphere using a vacuum staining device (VSC4R1H, Filgen), and a STEM image is obtained using a scanning transmission electron microscope (JEM2800, JEOL). Under the above staining conditions, there is a difference in the degree of staining between the crystalline resin and the amorphous resin, so the presence of the matrix domain structure can be confirmed by the contrast difference.

[0115] The observation conditions are set as follows: acceleration voltage is 200 kV, STEM probe size is 1 nm, image size is 1024×1024 pixels, and magnification is 30000, and a dark field (STEM-DF) image is acquired.

[0116] Contrast and Brightness are adjusted so that the brightness when the maximum number of pixels is present in the part mainly composed of resin components becomes 150 in the brightness histogram by IMAGE J shown below.

[0117] If the brightness is between 140 and 160, you can adjust the brightness using Microsoft Photos.

[0118] <Method of measuring weight-average particle size (D4) and number-average particle size (D1) of toner particles> A precision particle size distribution measuring device using the pore electrical resistance method (product name: Coulter Counter Multisizer 3) and dedicated software (product name: Beckman Coulter Multisizer 3 Version 3.51, manufactured by Beckman Coulter, Inc.) are used. The aperture diameter is 100 μm, and measurements are performed with an effective number of measurement channels of 25,000, and the measurement data is analyzed and calculated. The electrolyte solution used for the measurement is one in which special grade sodium chloride is dissolved in ion-exchanged water to a concentration of 1 mass%, for example, ISOTON II (product name) manufactured by Beckman Coulter, Inc. can be used. Note that before performing the measurement and analysis, the dedicated software is set up as follows.

[0119] In the "Change Standard Measurement Method (SOM) screen" of the dedicated software, set the total count number in the control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using (standard particle 10.0 μm, manufactured by Beckman Coulter). Press the threshold / noise level measurement button to automatically set the threshold and noise level. In addition, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II (trade name), and check the aperture tube flush after measurement.

[0120] In the "Pulse to particle size conversion setting screen" of the dedicated software, set the bin interval to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range to 2 μm to 60 μm.

[0121] The specific measurement method is as follows. (1) Pour 200 mL of the electrolyte solution into a 250 mL round-bottom glass beaker made exclusively for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, use the "aperture flush" function of the analysis software to remove dirt and air bubbles from inside the aperture tube. (2) 30 mL of the aqueous electrolyte solution is placed in a 100 mL flat-bottom glass beaker, and 0.3 mL of a diluted solution of Contaminon N (trade name) (a 10% aqueous solution of a neutral detergent for cleaning precision measuring instruments, manufactured by Wako Pure Chemical Industries, Ltd.) diluted 3 times by mass with ion-exchanged water is added thereto. (3) A predetermined amount of ion-exchanged water and 2 mL of Contaminon N (trade name) are added to the water tank of an ultrasonic disperser (product name: Ultrasonic Dispersion System Tetora150, manufactured by Nikkaki Bios Co., Ltd.) that has two built-in oscillators with an oscillation frequency of 50 kHz and a phase shift of 180 degrees and an electrical output of 120 W. (4) The beaker (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolyte solution in the beaker is maximized. (5) While the electrolyte solution in the beaker in (4) is irradiated with ultrasonic waves, 10 mg of toner (particles) is added little by little to the electrolyte solution and dispersed. Then, ultrasonic dispersion treatment is continued for another 60 seconds. During ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to 10°C to 40°C. (6) Using a pipette, the electrolyte solution (5) in which the toner (particles) is dispersed is dropped into the round-bottom beaker (1) placed in the sample stand, and the measurement concentration is adjusted to 5%. Then, the measurement is continued until the number of particles measured reaches 50,000. (7) The measurement data is analyzed using the dedicated software that comes with the device, and the weight average particle size (D4) is calculated. Note that when the dedicated software is set to Graph / Volume %, the "Average diameter" on the "Analysis / Volume Statistics (Arithmetic Mean)" screen is the weight average particle size (D4). When the dedicated software is set to Graph / Number %, the "Average diameter" on the "Analysis / Number Statistics (Arithmetic Mean)" screen is the number average particle size (D1).

[0122] [Configuration included in the embodiment of the present invention] The disclosure of this embodiment includes the following configuration. (Configuration 1) A toner having toner particles containing a binder resin, a pigment, and a pigment dispersant, The binder resin contains a crystalline resin in an amount of 20.0% by mass or more and 100.0% by mass or less, The pigment dispersant has a structure represented by the above formula (1) and a polymer moiety containing a monomer unit represented by the above formula (3), the content of the structure represented by formula (1) in the pigment dispersant is 1.0% by mass or more and 15.0% by mass or less, the content of the monomer unit represented by the formula (3) in the pigment dispersant is 45.0% by mass or more and 80.0% by mass or less, The toner is characterized in that the weight average molecular weight (Mw) of the pigment dispersant is 10,000 or more and 50,000 or less. (Configuration 2) In the structure represented by the formula (1), R2 to R 11 At least one of R2 to R3 represents a group represented by the formula (2-1). 11 The toner according to embodiment 1, wherein adjacent groups of the formula (2-2) are each a group represented by the formula (2-2). (Configuration 3) The toner according to configuration 1, wherein the structure represented by formula (1) is a structure represented by formula (4). (Configuration 4) The toner according to any one of Configurations 1 to 3, wherein the pigment dispersant has a melting point peak attributable to the polymer moiety at 50° C. or higher and 70° C. or lower in DSC measurement. (Configuration 5) The binder resin contains an amorphous resin, 5. The toner according to any one of Configurations 1 to 4, wherein when a cross-section of the toner particle is observed with a scanning transmission electron microscope, a matrix-domain structure is observed on the cross-section, the crystalline resin is contained as a main component in the matrix, and the amorphous resin is contained as a main component in the domain. (Configuration 6) The toner according to 1, wherein the crystalline resin contains a structure represented by the above formula (5). (Configuration 7) The toner according to any one of Configurations 1 to 6, wherein a polarity parameter P1 of the pigment dispersant and a polarity parameter P2 of the crystalline resin satisfy the following formula: │P1-P2│≦0.10 (P1 indicates the volume fraction of acetonitrile at the precipitation point of the pigment dispersant, which is determined by adding 0.10 parts by mass of acetonitrile to a solution consisting of 0.05 parts by mass of the pigment dispersant and 1.48 parts by mass of chloroform. P2 indicates the volume fraction of acetonitrile at the precipitation point of the crystalline resin when 0.10 parts by mass of acetonitrile is added to a solution consisting of 0.05 parts by mass of the crystalline resin and 1.48 parts by mass of chloroform. (Configuration 8) The toner according to any one of Configurations 1 to 7, wherein the toner particles contain a wax, and the number average molecular weight (Mn) of the wax is 300 or more and 3,000 or less. (Configuration 9) The toner according to configuration 8, wherein the wax is an ester wax. (Configuration 10) The toner according to configuration 9, wherein the wax is an ester of a tetrahydric or more and an octahydric or less alcohol and an aliphatic monocarboxylic acid, or an ester of a tetrahydric or more and an octahydric or less carboxylic acid and an aliphatic monoalcohol. (Configuration 11) The toner according to any one of Configurations 1 to 10, wherein the pigment comprises a pigment selected from the group consisting of: Carbon black; CI Pigment Yellow 74, 93, 139, 155, 180, 185; CI Pigment Red 31, 122, 150, 170, 258, 269; CI Pigment Blue 15:3, 15:4 EXAMPLES

[0123] The present invention will be specifically described with reference to the following Production Examples and Examples. However, these do not limit the present invention in any way. In the Production Examples and Examples, "parts" and "%" are all by mass unless otherwise specified.

[0124] <Production example of polymer part (P-1)> Into a reaction vessel, 100.0 parts of xylene, 69.9 parts of behenyl acrylate, 28.4 parts of styrene, 1.7 parts of methacrylic acid, and 11.27 parts of methacrylic acid were charged, and the mixture was kept at 70°C while purging with nitrogen. Then, 1.5 parts of azobis(isobutyric acid)dimethyl was dissolved in 1.0 parts of xylene as a polymerization initiator, and the solution was dropped into the reaction vessel over 3 hours. After the dropwise addition, the reaction vessel was kept at 70°C for 3 hours to carry out polymerization. Then, the liquid temperature was raised to 170°C, and the solvent was removed by distillation under a reduced pressure of 1 hPa for 3 hours, to obtain a polymer portion (P-1).

[0125] <Production examples of polymer segments (P-2) to (P-18)> Polymer segments (P-2) to (P-18) were obtained in the same manner as in the production example of polymer segment (P-1), except that the raw materials were changed as shown in Table 1. The composition ratios of polymer segments (P-2) to (P-18) are shown in Table 1.

[0126] [Table 1] BEA: Behenyl acrylate St: styrene MA: Methyl acrylate LMA: Lauryl methacrylate 2-MTA: 2-Methoxyethyl acrylate MAA: Methacrylic acid

[0127] <Production Example of Pigment Adsorption Site Precursor (A-1)> First, 25.0 parts of m-nitroaniline, 15.4 parts of diketene, and 15.0 parts of acetone were added to 140 parts of acetic acid, and the mixture was stirred for 3 hours at 65° C. After the reaction was completed, the mixture was poured into 1200 parts of water, and then filtered to obtain 38.4 parts of compound (1) (yield 96.0%).

[0128] Next, 142 parts of N,N-dimethylformamide and 30.8 parts of concentrated hydrochloric acid were added to 15.0 parts of 5-amino-2-benzimidazolinone, and the mixture was cooled to below 5°C with ice. 7.25 parts of sodium nitrite dissolved in 50.0 parts of water was added to this solution and stirred at the same temperature for 1 hour (diazonium salt solution). 21.9 parts of compound (1) and 68.4 parts of calcium carbonate were added to 142 parts of N,N-dimethylformamide, and the mixture was cooled to below 5°C with ice. The above diazonium salt solution was added and reacted at below 5°C for 3 hours. After the reaction was completed, the reaction solution was filtered and the solvent was distilled off under reduced pressure. The precipitate was washed with dilute hydrochloric acid, water, and methanol to obtain 36.0 parts of compound (2) (yield 94.3%).

[0129] The obtained compound (2) was added to 203 parts of 1,4-dioxane, and a solution of 12.4 parts of sodium hydrosulfide dissolved in 80 parts of water was added dropwise at room temperature. After the dropwise addition, the solution was heated and stirred at 50°C for 26 hours. After the reaction was completed, the reaction solution was poured into water, and the precipitate was filtered off and washed with dilute hydrochloric acid, water, and methanol to obtain 10.0 parts of pigment adsorption site precursor (A-1) (compound (3)) (yield 50.6%). The structure of the pigment adsorption site precursor (A-1) is shown in Table 2.

[0130] <Production Examples of Pigment Adsorption Site Precursors (A-2) and (A-3)> Pigment adsorption site precursors (A-2) and (A-3) were obtained in the same manner as in the production example of pigment adsorption site precursor 1, except that the compounds used were changed so as to obtain the compositions shown in Table 2.

[0131] [Table 2]

[0132] <Production example of pigment dispersant Sy-1> 10.0 parts of polymer (P-1) was dissolved in 100 parts of chloroform, 1.5 parts of thionyl chloride was added dropwise, and the mixture was stirred at room temperature for 24 hours. The reaction solution was then concentrated to remove chloroform and excess thionyl chloride, and the resulting resin solid was recovered and dissolved again in 60.0 parts of N,N-dimethylacetamide at 70°C under a nitrogen atmosphere. 1.5 parts of pigment adsorption site precursor (A-1) was added and the mixture was stirred at 70°C under a nitrogen atmosphere for 3 hours. After the reaction was completed, the reaction solution was concentrated and then reprecipitated with methanol to obtain 9.87 parts of pigment dispersant Sy-1.

[0133] The composition and physical properties (weight average molecular weight (Mw), melting point (Tm), and polarity parameter P1) of the obtained pigment dispersant Sy-1 are shown in Table 3.

[0134] The structural formula of the pigment dispersant Sy-1 is represented by the following formula, and R in the above formula (4) 17 is a carboxylic acid amide bond (-CONH-) as a linking group, and is bonded to the polymer portion.

[0135] [ka]

[0136] <Production examples of pigment dispersants Sy-2 to Sy-18> Pigment dispersants Sy-2 to Sy-18 were obtained in the same manner as in the production example of pigment dispersant Sy-1, except that the composition was changed to that shown in Table 3. The compositions and physical properties of pigment dispersants Sy-2 to Sy-18 are shown in Table 3.

[0137] [Table 3]

[0138] <Production Example of Crystalline Resin C-1> The following materials were placed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. Toluene 100.0 parts Behenyl acrylate 80.0 parts Styrene 20.0 parts Polymerization initiator: 0.5 parts t-butyl peroxypivalate (NOF Corp.: Perbutyl PV)

[0139] The inside of the reaction vessel was heated to 70°C while stirring at 200 rpm to carry out a polymerization reaction for 12 hours, and a solution in which the polymer of the monomer composition was dissolved in toluene was obtained. Toluene and residual monomers were then distilled off at 160°C and 1 hPa to obtain crystalline resin C-1.

[0140] <Production Example of Crystalline Resin C-2> Crystalline resin C-2 was obtained in the same manner as in preparation of crystalline resin C-1, except that in the preparation of crystalline resin C-1, 60.0 parts of behenyl acrylate, 15 parts of styrene, and 25 parts of methacrylonitrile were used.

[0141] <Production Example of Crystalline Resin C-3> In a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dehydration tube, and a pressure reducing device, 118.0 parts of sebacic acid and 69.0 parts of 1,6-hexanediol were added and heated to a temperature of 130°C while stirring. After adding 0.7 parts of titanium (IV) isopropoxide as an esterification catalyst, the temperature was raised to 160°C and polycondensed for 5 hours. Thereafter, the temperature was raised to 180°C and the reaction was continued while reducing the pressure until the desired molecular weight was obtained, to obtain crystalline resin C-3.

[0142] <Production Example of Crystalline Resin C-4> In a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dehydration tube, and a pressure reducing device, 118.0 parts of sebacic acid and 69.0 parts of 1,6-hexanediol were added and heated to a temperature of 130°C while stirring. After adding 0.7 parts by mass of titanium (IV) isopropoxide, the temperature was raised to 160°C and polycondensed over 5 hours. 7.0 parts by mass of acrylic acid and 50.0 parts by mass of styrene were dropped over 1 hour. After continuing stirring for 1 hour while maintaining the temperature at 160°C, the monomer of the styrene resin component was removed at 8.3 kPa for 1 hour. The temperature was then raised to 210°C and reacted until the desired molecular weight was reached to obtain crystalline resin C-4.

[0143] Table 4 shows the compositions and physical properties (weight average molecular weight (Mw) and polarity parameter P2) of crystalline resins C-1 to C-4.

[0144] [Table 4]

[0145] <Production example of black toner 1> [Preparation process of colorant dispersion 1] Styrene monomer 100.0 parts Carbon black (CB) 20.0 parts (Nipex35: manufactured by Oorion Engineered Carbons) Pigment dispersant Sy-1 2.0 parts The above materials were introduced into an attritor (manufactured by Mitsui Mining Co., Ltd.) and stirred at 200 rpm at 25° C. for 180 minutes using zirconia beads (200 parts) having a radius of 2.5 mm to prepare colorant dispersion 1.

[0146] [Preparation of toner composition solution] Colorant dispersion 1 48.8 parts Styrene 4.0 parts n-Butyl acrylate (BA) 19.0 parts ·Crystalline resin C-1 35.0 parts Dipentaerythritol hexastearate 10.0 parts The above materials were mixed and heated to 65° C., and then uniformly dissolved and dispersed for 60 minutes at 5,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain toner composition solution 1.

[0147] [Preparation process of dispersion liquid (aqueous medium)] In a 2-liter four-neck flask equipped with a high-speed stirring device TK-Homomixer, 710 parts of ion-exchanged water were charged with 450 parts of 0.1M-Na3PO4 aqueous solution and heated to 60°C. Then, 67.7 parts of 1.0M-CaCl2 aqueous solution were gradually added to obtain an aqueous medium 1 containing a calcium phosphate compound.

[0148] [Granulation process] While maintaining the temperature of the aqueous medium 1 at 60° C. and the rotation speed of the stirring device at 12,500 rpm, the toner composition solution 1 was poured into the aqueous medium 1, and 9.0 parts of t-butyl peroxypivalate as a polymerization initiator was added. Granulation was continued for 10 minutes while maintaining the stirring device at 12,500 rpm.

[0149] [Polymerization process] The high-speed stirrer was changed to a stirrer equipped with a propeller stirring blade, and polymerization was carried out for 5.0 hours while stirring at 200 rpm and maintaining the temperature at 70°C. Thereafter, the temperature was raised to 98°C and heated for 3.0 hours to remove residual monomers, thereby obtaining a black toner particle dispersion in which black toner particles 1 are dispersed.

[0150] Hydrochloric acid was added to the obtained black toner particle 1 dispersion liquid to adjust the pH to 1.4, and the dispersion was stirred for 1 hour to dissolve the calcium phosphate salt. This was subjected to solid-liquid separation in a pressure filter under a pressure of 0.4 MPa to obtain a toner cake. Next, ion-exchanged water was added to the pressure filter until it was filled with water, and the mixture was washed under a pressure of 0.4 MPa. This washing operation was repeated three times, and then the mixture was dried to obtain black toner particle 1. The weight average particle size (D4) of the obtained black toner particles was 6.9 μm.

[0151] To 100.0 parts of the obtained black toner particles 1, 1.5 parts (number average primary particle diameter: 10 nm) of hydrophobic silica fine powder surface-treated with hexamethyldisilazane was added, and a mixing process was carried out for 300 seconds in a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) to obtain black toner 1. The composition and physical properties of black toner 1 are shown in Table 5.

[0152] <Production examples of black toner 2-27> Black toners 2 to 27 were obtained in the same manner as in the production example of black toner 1, except that the composition of black toner particles 1 was changed as shown in Table 5. Black toners 2 to 27 are shown in Table 5.

[0153] [Table 5-1]

[0154] [Table 5-2]

[0155] <Production example of magenta toner 1> [Preparation process of colorant dispersion 2] Styrene monomer 100.0 parts Pigment Red 122 (PR-122) 12.5 parts (Toner Magenta E [Clariant]) Pigment Red 150 (PR-150) 7.5 parts (Fuji Fast Carmine 522 [manufactured by Fuji Pigment Co., Ltd.]) Pigment dispersant (Sy-1) 2.0 parts The above materials were introduced into an attritor (manufactured by Mitsui Mining Co., Ltd.) and stirred at 200 rpm at 25° C. for 180 minutes using zirconia beads (200 parts) having a radius of 2.5 mm to prepare colorant dispersion 2.

[0156] Thereafter, magenta toner 1 was obtained in the same manner as for black toner 1. The composition and physical properties of magenta toner 1 obtained are shown in Table 6.

[0157] <Production example of magenta toners 2 to 5> Magenta toners 2 to 5 were obtained in the same manner as in the production example of magenta toner 1, except that the pigment dispersant of magenta toner 1 was changed as shown in Table 6. Magenta toners 2 to 5 are shown in Table 6.

[0158] [Table 6]

[0159] <Production Example of Yellow Toner 1> [Preparation process of colorant dispersion 2] Styrene monomer 100.0 parts Pigment Yellow 155 (PY-155) 20.0 parts (Paliotol Yellow D1155 [BASF]) Pigment dispersant (Sy-1) 2.0 parts The above materials were introduced into an attritor (manufactured by Mitsui Mining Co., Ltd.) and stirred at 200 rpm at 25° C. for 180 minutes using zirconia beads (200 parts) having a radius of 2.5 mm to prepare colorant dispersion 2.

[0160] Thereafter, yellow toner 1 was obtained in the same manner as black toner 1. The composition and physical properties of yellow toner 1 thus obtained are shown in Table 7.

[0161] <Production Examples of Yellow Toners 2 to 5> Yellow toners 2 to 5 were obtained in the same manner as in the production example of yellow toner 1, except that the pigment of yellow toner 1 was changed as shown in Table 7. Yellow toners 2 to 5 are shown in Table 7.

[0162] [Table 7]

[0163] <Production example of cyan toner 1> [Preparation process of colorant dispersion 2] Styrene monomer 100.0 parts Pigment Blue 15:3 20.0 parts (ECB-308 [manufactured by Dainichi Seika Chemicals Co., Ltd.]) Pigment dispersant (Sy-1) 2.0 parts The above materials were introduced into an attritor (manufactured by Mitsui Mining Co., Ltd.) and stirred at 200 rpm at 25° C. for 180 minutes using zirconia beads (200 parts) having a radius of 2.5 mm to prepare colorant dispersion 2.

[0164] Thereafter, cyan toner 1 was obtained in the same manner as black toner 1. The composition and physical properties of the obtained cyan toner 1 are shown in Table 8.

[0165] <Production Example of Cyan Toner 2 to 5> Cyan toners 2 to 5 were obtained in the same manner as in the production example of cyan toner 1, except that the pigment dispersant of cyan toner 1 was changed as shown in Table 8. Cyan toners 2 to 5 are shown in Table 8.

[0166] [Table 8]

[0167] <Image evaluation> The image evaluation was performed using a commercially available color laser printer [HP LaserJet Enterprise Color M555dn] that was partially modified so that it could operate with only one color process cartridge installed. The printer was also modified so that the fixing unit temperature could be changed to any desired value.

[0168] The toner was removed from the black toner process cartridge installed in this color laser printer, the inside was cleaned with an air blower, and then each toner (250 g) was introduced into the process cartridge, and the process cartridge refilled with toner was installed in the color laser printer, and the following image evaluation was performed. The specific image evaluation items are as follows.

[0169] [Evaluation method for coloring strength] A rectangular solid image of 6.5 cm x 14.0 cm is printed in the center of the transfer material (toner load: 0.45 mg / cm 2 ) was output as an evaluation image. The image density in the evaluation image was measured to evaluate the coloring power. The image density was measured using an X-Rite color reflection densitometer (X-Rite404A). The density was measured at five points in the solid image area: top right, top left, center, bottom right, and bottom left, and the average value was used to evaluate the image density. LETTER size glossy paper (HP Brochure Paper 150g, Glossy) was used as the transfer material. (Evaluation Criteria) A: Image density is 1.60 or more B: Image density is 1.50 or more and less than 1.60 C: Image density is 1.40 or more and less than 1.50 D: Image density is less than 1.40

[0170] [Evaluation method for low-temperature fixability] Solid image on transfer material (toner load: 0.45 mg / cm 2 The fixing temperature was measured by a non-contact thermometer on the surface of the fixing roller. The transfer material was LETTER size plain paper (Vitality, XEROX, 75 g / m 2 ) was used. (Evaluation Criteria) A: Low temperature fixing start temperature is 115℃ or less B: Low-temperature fixing start temperature is 120°C or higher and 130°C or lower C: Low temperature fixing start temperature is 135℃ or higher and 145℃ or lower D: Low temperature fixing start temperature is 150℃ or higher

[0171] [Method for evaluating hot offset resistance] A fixed image was prepared in the same manner as in the above evaluation method, and the maximum fixing temperature was evaluated. The maximum fixing temperature is defined as the highest temperature at which offset does not occur. (Evaluation Criteria) A: Maximum fixing temperature is 205℃ or higher B: Maximum fixing temperature is 195℃ or 200℃ C: Maximum fixing temperature is 185℃ or 190℃ D: Maximum fixing temperature is 180℃ or less

[0172] [Evaluation method for storage stability (heat resistance)] 5 g of each toner was placed in a 50 mL resin cup and left to stand for 3 days at a temperature of 60° C. and a humidity of 10% RH, and the presence or absence of aggregates was examined and evaluated according to the following criteria. (Evaluation Criteria) A: No clumps formed B: Slight clumps formed, crumbles when lightly pressed with fingers C: Agglomerates form, but do not crumble when lightly pressed with fingers D: Completely aggregated

[0173] <Streak (developability) evaluation method> After completing a printout test of 30,000 sheets of images with a horizontal line coverage rate of 1% in a high temperature and high humidity environment (temperature 32°C / humidity 85%RH), a halftone image (toner loading amount: 0.25mg / cm2) was printed out on LETTER size plain paper (Vitality, XEROX, 75g / m2). The halftone image was observed for the presence or absence of vertical streaks in the paper ejection direction, and the developability was evaluated as follows. (Evaluation Criteria) A: Not occurred B: Vertical stripes in the paper ejection direction appear in 1 to 3 places on the halftone image. C: Four to six vertical streaks in the ejection direction appear on the halftone image. D: Seven or more vertical lines appear in the paper ejection direction on the halftone image, or vertical lines with a width of 0.5 mm or more appear.

[0174] [Examples 1 to 20] In Examples 1 to 20, the above evaluations were carried out using black toners 1 to 20, respectively. The evaluation results are shown in Table 9.

[0175] [Comparative Examples 1 to 7] In Comparative Examples 1 to 7, the above evaluations were carried out using black toners 21 to 27, respectively. The evaluation results are shown in Table 9. In addition, in Comparative Example 4, the toner completely aggregated in the evaluation of heat resistance, so that evaluations of low temperature fixability, hot offset resistance, and developability were not carried out.

[0176] [Table 9]

[0177] [Examples 21 to 35] In Examples 21 to 25, the above evaluation was performed using magenta toners 1 to 5, respectively. In Examples 26 to 30, the above evaluation was performed using yellow toners 1 to 5, respectively. In Examples 31 to 35, the above evaluation was performed using cyan toners 1 to 5, respectively. The evaluation results are shown in Table 10.

[0178] [Table 10]

Claims

1. A toner having toner particles containing a binder resin, a pigment, and a pigment dispersant, the binder resin contains a crystalline resin in an amount of 20.0% by mass or more and 100.0% by mass or less, The pigment dispersant has a structure represented by the following formula (1) and a polymer moiety containing a monomer unit represented by the following formula (3), the content of the structure represented by the following formula (1) in the pigment dispersant is 1.0% by mass or more and 15.0% by mass or less, the content of the monomer unit represented by the following formula (3) in the pigment dispersant is 45.0% by mass or more and 80.0% by mass or less, The toner is characterized in that the weight average molecular weight (Mw) of the pigment dispersant is 10,000 or more and 50,000 or less. 【Chemistry 1】 (In formula (1), R 1 represents a substituted alkyl group, an unsubstituted alkyl group, a substituted phenyl group, or an unsubstituted phenyl group, R 2 ~R 11 at least one of the groups is a linking group to the polymer moiety or a moiety that is bonded to the polymer moiety via a single bond, R that is not a linking group 2 ~R 11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an amino group, a cyano group, a trifluoromethyl group, a carboxy group, or a group represented by the following formula (2-1), or R 2 ~R 11 The adjacent groups are groups represented by the following formula (2-2): 【Chemistry 2】 (In formula (2-1), * represents R in formula (1). 2 ~R 6 , or R 7 ~R 11 represents the bonding position to the aromatic ring having the formula: R 12 represents a hydrogen atom, a substituted or unsubstituted alkyl group, an aralkyl group, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group. A 1 represents an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13 represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group. 【Transformation 3】 (In formula (2-2), * represents R in formula (1). 2 ~R 6 , or R 7 ~R 11 represents the bonding position to the aromatic ring having the formula: The group represented by formula (2-2) is R 2 ~R 6 , or R 7 ~R 11 A five-membered heterocycle is formed by bonding to an aromatic ring having the formula: A 2 represents an oxygen atom, a sulfur atom, or NR 13 represents a group, R 13 represents a hydrogen atom, a substituted or unsubstituted alkyloxycarbonyl group, or a substituted or unsubstituted aralkyloxycarbonyl group. 【Chemistry 4】 (In formula (3), R 14 represents a hydrogen atom or a methyl group, L 1 represents an ester bond or an amide bond, m represents an integer of 20 or more and 30 or less.

2. In the structure represented by the formula (1), R 2 ~R 11 At least one of R represents a group represented by the formula (2-1), or 2 ~R 11 2. The toner according to claim 1, wherein adjacent groups of the formula (2-1) are groups represented by the formula (2-2).

3. 2. The toner according to claim 1, wherein the structure represented by formula (1) is a structure represented by formula (4): 【Transformation 5】 (In formula (4), R 15 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted phenyl group. R 16 ~R 20 At least one of these is a linking group that forms a bond with the polymer moiety. R that is not a linking group 16 ~R 20 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group, an amino group, a cyano group, a trifluoromethyl group, or a carboxy group.

4. The toner according to claim 1 or 2, wherein the pigment dispersant has a melting point peak at 50° C. or higher but 70° C. or lower, which is derived from the polymer moiety, as measured by DSC.

5. The binder resin contains an amorphous resin, 3. The toner according to claim 1, wherein when a cross section of the toner particle is observed with a scanning transmission electron microscope, a matrix-domain structure is observed in the cross section, the crystalline resin is contained as a main component in the matrix, and the amorphous resin is contained as a main component in the domain.

6. 2. The toner according to claim 1, wherein the crystalline resin contains a structure represented by the following formula (5): 【Transformation 6】 (In formula (5), R 21 represents a hydrogen atom or a methyl group, L 2 represents a single bond, an ester bond, or an amide bond; n represents an integer of 15 or more and 30 or less.

7. 3. The toner according to claim 1, wherein a polarity parameter P1 of the pigment dispersant and a polarity parameter P2 of the crystalline resin satisfy the following formula: |P1-P2|≦0.10 (P1 represents the volume fraction of acetonitrile at the precipitation point of the pigment dispersant, which is determined by adding 0.10 parts by mass of acetonitrile to a solution consisting of 0.05 parts by mass of the pigment dispersant and 1.48 parts by mass of chloroform. P2 indicates the volume fraction of acetonitrile at the precipitation point of the crystalline resin when 0.10 parts by mass of acetonitrile is added to a solution consisting of 0.05 parts by mass of the crystalline resin and 1.48 parts by mass of chloroform.

8. 3. The toner according to claim 1, wherein the toner particles contain a wax, and the number average molecular weight (Mn) of the wax is 300 or more and 3,000 or less.

9. 9. The toner according to claim 8, wherein the wax is an ester wax.

10. 10. The toner according to claim 9, wherein the wax is an ester of a tetravalent or more and octavalent alcohol and an aliphatic monocarboxylic acid, or an ester of a tetravalent or more and octavalent carboxylic acid and an aliphatic monoalcohol.

11. 3. The toner according to claim 1, wherein the pigment comprises a pigment selected from the following group: Carbon black; C.I. Pigment Yellow 74, 93, 139, 155, 180, 185; C.I. Pigment Red 31, 122, 150, 170, 258, 269; C.I. Pigment Blue 15:3, 15:4

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