Electrostatic charge image developing toner

Abstract

To provide an electrostatic charge image developing toner excellent in smear property, and its manufacturing method.SOLUTION: An electrostatic charge image developing toner contains a binder resin and colorant. The binder resin contains an amorphous polyester resin A as a polycondensate of polyethylene terephthalate, an alcohol component, and a carboxylic acid component. When a value obtained by dividing the total number of -NH-groups and -NH2 groups in one molecule by molecular weight is set as NH group amount, the colorant contains an organic yellow pigment with the NH group amount of 4.0 mmol / g or more and 15.0 mmol / g or less. Also, a manufacturing method of the electrostatic charge image developing toner is provided.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an electrostatic charge image developing toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, etc., and a method for manufacturing the same.

Background Art

[0002] In recent years, as a yellow pigment used in an electrostatic charge image developing toner, C.I. Pigment Yellow 74 is widely known, but switching to other yellow pigments has been studied from the viewpoints of weather resistance and safety.

[0003] For example, Patent Document 1 proposes a yellow pigment having three or more aromatic rings in one molecule and a molecular weight of 600 or more and 1500 or less.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, toners containing organic yellow pigments have a problem that the smear property of the printed image is not sufficient.

[0006] The present invention relates to an electrostatic charge image developing toner excellent in smear property and a method for manufacturing the same.

Means for Solving the Problems

[0007] The present invention is 〔1〕 An electrostatic charge image developing toner containing a binder resin and a colorant, wherein the binder resin contains an amorphous polyester resin A which is a polycondensate of polyethylene terephthalate, an alcohol component, and a carboxylic acid component, and the colorant has a -NH- group and -NH in one molecule2 a toner for developing an electrostatic image, the toner containing an organic yellow pigment having an NH group amount of 4.0 mmol / g or more and 15.0 mmol / g or less, the NH group amount being calculated by dividing the total number of NH groups by the molecular weight; [2] A method for producing the toner for developing electrostatic images according to [1] above, comprising the steps of melting and kneading at least the binder resin and the colorant, and pulverizing the resulting kneaded mixture. Regarding. Effect of the Invention

[0008] The toner for developing electrostatic images of the present invention exhibits an excellent effect in terms of smear resistance. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The toner for developing electrostatic images of the present invention (hereinafter, simply referred to as "toner") is characterized by the combination of an amorphous polyester resin (amorphous polyester resin A) using polyethylene terephthalate (PET) and an organic yellow pigment having a large amount of NH groups. The reason why the toner for developing electrostatic images of the present invention has excellent smear resistance is not clear, but is presumed to be as follows.

[0010] In the polycondensation reaction of the alcohol component, carboxylic acid component, and PET, the PET undergoes depolymerization and is incorporated into the polyester resin chain through an ester exchange reaction, but it is not completely randomized, and units that can be called PET segments exist in the resulting resin. These PET segments have a high concentration of ester groups and tend to interact with organic yellow pigments that have a high amount of NH groups. Therefore, when fixed, the amorphous polyester resin A forms a pseudo-crosslinked structure via the organic yellow pigment, which is thought to improve the impact resistance of the printed material and provide excellent smear resistance.

[0011] The amorphous polyester resin A is a polycondensation product of PET, an alcohol component, and a carboxylic acid component.

[0012] PET is produced by polycondensation reaction of an alcohol component and a carboxylic acid component, and / or ethylene glycol and terephthalic acid produced by depolymerization of a part of PET are subjected to polycondensation reaction as raw material monomers and incorporated into the polyester resin. PET is an equimolar polycondensate of ethylene glycol and terephthalic acid, and the amounts of the alcohol component and carboxylic acid component described below include ethylene glycol and terephthalic acid constituting PET respectively.

[0013] PET may be virgin PET or recycled PET. Recycled PET refers to a product obtained by collecting used PET, performing washing, sorting with other materials as necessary, then pulverizing, decomposing the pulverized product into monomer units by depolymerization, and resynthesizing using this as raw material.

[0014] In the present invention, PET is preferably PET having a relatively low IV value, i.e., low molecular weight, compared to conventionally used PET. By introducing PET with a low IV value (low molecular weight) into the polyester resin, the depolymerization of PET proceeds more uniformly.

[0015] From the above viewpoints, the IV value of PET is preferably 0.40 or more, more preferably 0.45 or more, still more preferably 0.50 or more, still more preferably 0.55 or more, and from the viewpoints of low-temperature fixability and uniform depolymerization, preferably 0.85 or less, more preferably 0.80 or less, still more preferably 0.75 or less, still more preferably 0.70 or less, still more preferably 0.65 or less. The IV value is the intrinsic viscosity and is an index of molecular weight. The IV value of PET can be adjusted by the polycondensation time etc.

[0016] Examples of commercially available PETs with an IV value of 0.40 or more and 0.85 or less include RAMAPET L1 (manufactured by Indorama Ventures, IV value: 0.60), RAMAPET BF3067 (manufactured by Indorama Ventures, IV value: 0.65), RAMAPET N2G (manufactured by Indorama Ventures, IV value: 0.75), TRN-NTJ (manufactured by Teijin Limited, IV value: 0.53), TRN-RTJC (manufactured by Teijin Limited, IV value: 0.64), RAMAPET S1 (manufactured by Indorama Ventures, IV value: 0.84), UK-31 (manufactured by Utsumi Recycling Systems Co., Ltd., IV value: 0.67), and the like.

[0017] The content of PET with a low IV value is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and still more preferably 100% by mass in the total amount of PET subjected to polycondensation.

[0018] From the viewpoint of smearability, the content of PET in the amorphous polyester resin A is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 20 mol% or more, and preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, still more preferably 50 mol% or less, still more preferably 40 mol% or less, and still more preferably 30 mol% or less in the total amount of the alcohol component, the carboxylic acid component, and PET. When the amorphous polyester resin A is composed of two or more resins, the weighted average value of the PET content of each resin is defined as the PET content of the amorphous polyester resin A. Since PET is a polycondensate of ethylene glycol and terephthalic acid, dimethyl terephthalate, etc., it is converted with 1 mol of the unit of terephthalic acid - ethylene glycol (MW: 192). Therefore, the number of moles of PET = the number of moles of ethylene glycol units = the number of moles of terephthalic acid units.

[0019] From the viewpoint of smearability, the alcohol component preferably contains an alkylene oxide adduct of bisphenol A.

[0020] As the alkylene oxide adduct of bisphenol A, the compound represented by the formula (I):

[0021]

Chemical formula

[0022] (In the formula, OR and RO are oxyalkylene groups, R is an ethylene group and / or a propylene group, x and y represent the average number of moles of alkylene oxide added, and are positive numbers respectively. The value of the sum of x and y is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, more preferably 6 or less, and even more preferably 4 or less) The compound represented by the formula is preferred.

[0023] From the viewpoint of low-temperature fixing property, the content of the alkylene oxide adduct of bisphenol A in the alcohol component is preferably 25 mol% or more, more preferably 40 mol% or more, and even more preferably 55 mol% or more, and preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less. Here, the alcohol component is assumed to contain ethylene glycol units in PET.

[0024] Examples of other alcohol components include aliphatic diols, alicyclic diols, bisphenol A, etc.

[0025] As the aliphatic diol, aliphatic diols other than ethylene glycol are preferred, and examples include 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, neopentyl glycol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, etc.

[0026] Examples of the alicyclic diol include hydrogenated bisphenol A, etc.

[0027] Examples of the carboxylic acid component include aromatic dicarboxylic acid compounds and aliphatic dicarboxylic acid compounds.

[0028] Examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, terephthalic acid, anhydrides of these acids, and alkyl esters of these acids having 1 to 3 carbon atoms.

[0029] Examples of the aliphatic dicarboxylic acid compound include fumaric acid, maleic acid, succinic acid, succinic acid derivatives substituted with hydrocarbon groups, glutaric acid, adipic acid, sebacic acid, anhydrides of these acids, and alkyl esters of these acids having 1 to 3 carbon atoms.

[0030] From the viewpoint of softening point adjustment, a raw material monomer having a trivalency or higher may be used in the alcohol component and / or carboxylic acid component of the amorphous polyester resin A.

[0031] Examples of the alcohol having a trivalency or higher include sorbitol, pentaerythritol, glycerin, trimethylolpropane, and the like.

[0032] Examples of the carboxylic acid compound having a trivalency or higher include trimellitic acid, pyromellitic acid, anhydrides of these acids, and alkyl esters of these acids having 1 to 3 carbon atoms.

[0033] The content of the raw material monomer having a trivalency or higher is preferably 2 mol% or more, more preferably 4 mol% or more, and preferably 25 mol% or less, more preferably 20 mol% or less, based on the total amount of the alcohol component, carboxylic acid component, and PET.

[0034] A monohydric alcohol may be appropriately contained in the alcohol component, and a monohydric carboxylic acid compound may be appropriately contained in the carboxylic acid component.

[0035] In addition, in this specification, macromonomers and hydroxycarboxylic acids are not included in the alcohol component and the carboxylic acid component.

[0036] The equivalent ratio (COOH group / OH group) of the carboxylic acid component (including terephthalic acid units in PET) to the alcohol component (including ethylene glycol units in PET) is preferably 0.6 or more, more preferably 0.7 or more, still more preferably 0.8 or more, and preferably 1.3 or less, more preferably 1.2 or less.

[0037] The amorphous polyester resin A can be produced, for example, by polycondensing an alcohol component, a carboxylic acid component, and PET in an inert gas atmosphere, preferably in the presence of an esterification catalyst, and further, if necessary, in the presence of a cocatalyst, a polymerization inhibitor, etc., preferably at a temperature of 130°C or higher, more preferably 170°C or higher, and preferably 250°C or lower, more preferably 240°C or lower.

[0038] Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin(II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropoxybis(triethanolaminato) and titanium dihydroxybis(triethanolaminato). The amount of the esterification catalyst used is preferably 0.01 part by mass or more, more preferably 0.1 part by mass or more, and preferably 1.5 parts by mass or less, more preferably 1 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component, the carboxylic acid component, and PET. Examples of the cocatalyst for the esterification catalyst include gallic acid. The amount of the cocatalyst used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass or less, more preferably 0.1 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component, the carboxylic acid component, and PET. Examples of the polymerization inhibitor include tert-butylcatechol. The amount of the polymerization inhibitor used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass or less, more preferably 0.1 part by mass or less, based on 100 parts by mass of the total amount of the alcohol component, the carboxylic acid component, and PET.

[0039] In the present invention, the polyester resin may be a polyester resin modified to such an extent that its properties are not substantially impaired. Examples of the modified polyester resin include polyester resins grafted or blocked with phenol, urethane, epoxy, etc. by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, etc. Among the modified polyester resins, a urethane-modified polyester resin obtained by extending a polyester resin with a polyisocyanate compound is preferred.

[0040] The ester group concentration of the amorphous polyester resin A is preferably 3.5 mmol / g or more, more preferably 3.7 mmol / g or more, still more preferably 4.0 mmol / g or more, and preferably 12.0 mmol / g or less, more preferably 10.0 mmol / g or less, still more preferably 6.0 mmol / g or less. When two or more kinds of amorphous polyester resins A are used, the weighted average value of the ester group concentrations of the respective amorphous polyester resins A is taken as the ester group concentration of the amorphous polyester resin A.

[0041] In the present invention, the ester group concentration of the polyester resin is calculated from the following formula.

[0042]

Equation

[0043] 〔In the formula, A is the total amount of ester bonds (mol) formed when all the raw material monomers of the polyester resin have reacted, and B is the total mass (g) of the raw material monomers constituting the polyester resin. The parentheses in the formula indicate the units of the respective numerical values.〕

[0044] From the perspective of charge stability, the softening point of the amorphous polyester resin A is preferably 70 °C or higher, more preferably 90 °C or higher, still more preferably 100 °C or higher, and from the perspective of low-temperature fixability, it is preferably 170 °C or lower, more preferably 160 °C or lower, still more preferably 150 °C or lower.

[0045] The crystallinity of the resin is represented by the crystallinity index defined as the ratio of the softening point to the maximum peak temperature of endothermic heat measured by a differential scanning calorimeter, that is, [softening point / maximum peak temperature of endothermic heat]. An amorphous resin is a resin in which no endothermic peak is observed, or if an endothermic peak is observed, the crystallinity index exceeds 1.4 or is less than 0.6. On the other hand, a crystalline resin is a resin having a crystallinity index of 0.6 or higher and 1.4 or lower. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers and the manufacturing conditions (for example, reaction temperature, reaction time, cooling rate), etc. The maximum peak temperature of endothermic heat refers to the temperature of the peak with the largest peak area among the observed endothermic peaks. In the case of a crystalline resin, the maximum peak temperature of endothermic heat is taken as the melting point.

[0046] From the perspective of low-temperature fixability and fixing width, the amorphous polyester resin A may be composed of resins having different softening points. The difference in the softening points of the two resins is preferably 10 °C or higher, more preferably 20 °C or higher, and preferably 60 °C or lower, more preferably 40 °C or lower.

[0047] From the perspective of the fixing width, the softening point of the amorphous resin with a higher softening point (resin AH) is preferably 100 °C or higher, more preferably 110 °C or higher, still more preferably 120 °C or higher, and from the perspective of low-temperature fixability, it is preferably 170 °C or lower, more preferably 160 °C or lower, still more preferably 150 °C or lower.

[0048] Also, from the viewpoint of charge stability, the softening point of the amorphous resin (resin AL) with the lower softening point is preferably 70°C or higher, more preferably 90°C or higher, still more preferably 100°C or higher, and from the viewpoint of low-temperature fixability, it is preferably 130°C or lower, more preferably 125°C or lower, still more preferably 120°C or lower, and even more preferably 110°C or lower.

[0049] The mass ratio of resin AH to resin AL (resin AH / resin AL) is preferably 10 / 90 or more, more preferably 20 / 80 or more, still more preferably 30 / 70 or more, and preferably 90 / 10 or less, more preferably 80 / 20 or less, still more preferably 75 / 25 or less.

[0050] From the viewpoint of storage stability, the glass transition temperature of the amorphous polyester resin A is preferably 40°C or higher, more preferably 50°C or higher, and from the viewpoint of low-temperature fixability, it is preferably 80°C or lower, more preferably 70°C or lower.

[0051] From the viewpoint of charge stability, the acid value of the amorphous polyester resin A is preferably 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, and from the viewpoint of durability, it is preferably 20 mgKOH / g or less, more preferably 18 mgKOH / g or less.

[0052] From the viewpoint of durability, the content of the amorphous polyester resin A in the binder resin is preferably 70% by mass or more, more preferably 75% by mass or more, still more preferably 80% by mass or more, and from the viewpoint of low-temperature fixability, it is preferably 100% by mass or less, more preferably 99% by mass or less, still more preferably 97% by mass or less, and even more preferably 95% by mass or less.

[0053] From the viewpoint of low-temperature fixability, the binder resin preferably further contains a crystalline polyester resin C.

[0054] Crystalline polyester resin C is preferably a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound.

[0055] Examples of the aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-butenediol, 1,7-heptanediol, 1,8-octanediol, neopentyl glycol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, etc.

[0056] The number of carbon atoms of the aliphatic diol is 2 or more, preferably 6 or more, and from the viewpoint of adjusting the ester group concentration, it is preferably 14 or less, more preferably 12 or less.

[0057] From the viewpoint of improving the low-temperature fixability of the toner, the aliphatic diol preferably has a hydroxyl group at the end of the carbon chain, and more preferably is an α,ω-linear alkanediol.

[0058] The content of the aliphatic diol in the alcohol component is preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less.

[0059] Examples of the alcohol component other than the aliphatic diol include alkylene oxide adducts of bisphenol A, aromatic diols such as bisphenol A, hydrogenated bisphenol A, sorbitol, pentaerythritol, glycerin, and polyhydric alcohols such as trimethylolpropane.

[0060] Examples of the aliphatic dicarboxylic acid compound include succinic acid (number of carbon atoms: 4), fumaric acid (number of carbon atoms: 4), adipic acid (number of carbon atoms: 6), suberic acid (number of carbon atoms: 8), azelaic acid (number of carbon atoms: 9), sebacic acid (number of carbon atoms: 10), dodecanedioic acid (number of carbon atoms: 12), tetradecanedioic acid (number of carbon atoms: 14), anhydrides of these acids, alkyl esters of these acids having 1 to 3 carbon atoms in the alkyl group, and the like. Here, when the aliphatic dicarboxylic acid compound is an alkyl ester, the number of carbon atoms in the alkyl group is not included in the above number of carbon atoms.

[0061] The number of carbon atoms of the aliphatic dicarboxylic acid compound is preferably 4 or more, more preferably 6 or more, still more preferably 8 or more, and from the viewpoint of adjusting the ester group concentration, it is preferably 14 or less, more preferably 12 or less.

[0062] The content of the aliphatic dicarboxylic acid compound is preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more, still more preferably 80 mol% or more, and 100 mol% or less from the viewpoint of hydrophobicity in the carboxylic acid component.

[0063] Examples of other carboxylic acid components include aromatic dicarboxylic acid compounds such as phthalic acid, isophthalic acid, and terephthalic acid, and polyvalent carboxylic acid compounds such as trimellitic acid and pyromellitic acid.

[0064] The alcohol component may appropriately contain a monohydric alcohol, and the carboxylic acid component may appropriately contain a monohydric carboxylic acid compound.

[0065] The equivalent ratio (COOH group / OH group) of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component is preferably 0.8 or more, more preferably 0.9 or more from the viewpoint of charge stability, and preferably 1.2 or less, more preferably 1.1 or less from the viewpoint of low-temperature fixability.

[0066] The polycondensation reaction conditions of the alcohol component and carboxylic acid component of the crystalline polyester resin C are the same as those of the amorphous polyester resin A, except that the suitable reaction temperature is 120 °C or higher, more preferably 180 °C or higher, and 230 °C or lower, more preferably 220 °C or lower.

[0067] From the perspective of durability, the softening point of the crystalline polyester resin C is preferably 50 °C or higher, more preferably 65 °C or higher, still more preferably 70 °C or higher, and from the perspective of low-temperature fixability, it is preferably 140 °C or lower, more preferably 120 °C or lower, still more preferably 100 °C or lower.

[0068] From the perspective of durability, the melting point of the crystalline polyester resin C is preferably 50 °C or higher, more preferably 65 °C or higher, still more preferably 70 °C or higher, and from the perspective of low-temperature fixability, it is preferably 130 °C or lower, more preferably 120 °C or lower, still more preferably 100 °C or lower.

[0069] From the perspective of low-temperature fixability, the acid value of the crystalline polyester resin C is preferably 1 mgKOH / g or higher, more preferably 3 mgKOH / g or higher, and from the perspective of durability, it is preferably 30 mgKOH / g or lower, more preferably 25 mgKOH / g or lower.

[0070] From the perspective of low-temperature fixability, the content of the crystalline polyester resin C in the binder resin is preferably 1% by mass or higher, more preferably 3% by mass or higher, still more preferably 5% by mass or higher, and from the perspective of durability, it is preferably 30% by mass or lower, more preferably 25% by mass or lower, still more preferably 20% by mass or lower.

[0071] From the perspective of charge stability, the mass ratio of the crystalline polyester resin C to the amorphous polyester resin A (crystalline polyester resin C / amorphous polyester resin A) is preferably 1 / 99 or higher, more preferably 3 / 97 or higher, still more preferably 5 / 95 or higher, and preferably 30 / 70 or lower, more preferably 25 / 75 or lower, still more preferably 20 / 80 or lower.

[0072] Examples of other binder resins include vinyl resins such as styrene acrylic resins, epoxy resins, polycarbonates, polyurethanes, and composite resins containing two or more of these resins.

[0073] The total content of the amorphous polyester resin A and the crystalline polyester resin C is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, and still more preferably 100% by mass in the binder resin.

[0074] Also, the content of the binder resin is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more in the toner, and preferably less than 100% by mass, more preferably 98% by mass or less, still more preferably 95% by mass or less.

[0075] The colorant contains an organic yellow pigment having a specific NH group amount from the viewpoint of the interaction with the amorphous polyester resin A.

[0076] The NH group amount of the organic yellow pigment is 4.0 mmol / g or more, preferably 5.0 mmol / g or more, more preferably 6.0 mmol / g or more, and 15.0 mmol / g or less, preferably 12.5 mmol / g or less, more preferably 10.0 mmol / g or less. Here, the NH group amount is the value obtained by dividing the total number of -NH- groups and -NH 2 groups in one molecule by the molecular weight.

[0077] As the organic yellow pigment, at least one selected from the group consisting of benzimidazolone pigments, isoindoline-based pigments, and condensed disazo-based pigments is preferable from the viewpoint of achieving a desired NH group amount.

[0078] Examples of the benzimidazolone pigment include C.I. Pigment Yellow 180 (the number of -NH- groups and -NH 2Examples include the total number of groups = 6, molecular weight = 733, NH group amount = 8.2 mmol / g, etc.

[0079] Examples of isoindoline-based pigments include C.I. Pigment Yellow 185 (the total number of -NH- groups and -NH groups in one molecule = 4, molecular weight = 337, NH group amount = 11.9 mmol / g), etc. 2 Examples include the total number of groups = 4, molecular weight = 337, NH group amount = 11.9 mmol / g, etc.

[0080] Examples of condensed disazo-based pigments include C.I. Pigment Yellow 93 (the total number of -NH- groups and -NH groups in one molecule = 4, molecular weight = 937, NH group amount = 4.3 mmol / g), C.I. Pigment Yellow 95 (the total number of -NH- groups and -NH groups in one molecule = 4, molecular weight = 917, NH group amount = 4.4 mmol / g), etc. 2 Examples include the total number of groups = 4, molecular weight = 937, NH group amount = 4.3 mmol / g, etc. 2 Examples include the total number of groups = 4, molecular weight = 917, NH group amount = 4.4 mmol / g, etc.

[0081] From the perspective of the smear property of the toner, the organic yellow pigment used in the present invention is preferably at least one selected from benzimidazolone pigments and isoindoline-based pigments, and more preferably at least one selected from C.I. Pigment Yellow 180 (PY180) and C.I. Pigment Yellow 185 (PY185).

[0082] The content of the organic yellow pigment is preferably 1 part by mass or more, more preferably 2 parts by mass or more, still more preferably 3 parts by mass or more, and preferably 20 parts by mass or less, more preferably 18 parts by mass or less, still more preferably 15 parts by mass or less, based on 100 parts by mass of the amorphous polyester resin A.

[0083] The colorant may contain other colorants as long as the effects of the present invention are not impaired. However, the content of the organic yellow pigment is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and even more preferably 100% by mass in the colorant. Examples of other colorants include carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, disazo yellow, and the like.

[0084] The content of the colorant is preferably 1 part by mass or more, more preferably 2 parts by mass or more, still more preferably 3 parts by mass or more, and preferably 20 parts by mass or less, more preferably 18 parts by mass or less, still more preferably 15 parts by mass or less with respect to 100 parts by mass of the binder resin.

[0085] The toner for electrostatic charge image development of the present invention may contain, in addition to the binder resin and the colorant, additives such as a release agent, a charge control agent, magnetic powder, a fluidity improver, a conductivity adjuster, a reinforcing filler such as a fibrous substance, an antioxidant, and a cleaning property improver.

[0086] Examples of the release agent include hydrocarbon waxes such as polypropylene wax, polyethylene wax, ethylene-propylene copolymer wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and their oxides; ester waxes such as carnauba wax, montan wax, and their deacidified waxes, fatty acid ester waxes; fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts, etc. These can be used alone or in combination of two or more.

[0087] From the viewpoint of the transferability of the toner, the melting point of the release agent is preferably 60°C or higher, more preferably 70°C or higher, and from the viewpoint of low-temperature fixability, it is preferably 160°C or lower, more preferably 140°C or lower, still more preferably 120°C or lower, and even more preferably 110°C or lower.

[0088] From the viewpoints of the low-temperature fixability and offset resistance of the toner and the dispersibility in the binder resin, the content of the release agent is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, still more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass or less, still more preferably 7 parts by mass or less, based on 100 parts by mass of the binder resin.

[0089] The charge control agent is not particularly limited, and either a positive-charge control agent or a negative-charge control agent may be contained.

[0090] Examples of the positive-charge control agent include nigrosine dyes such as "Nigrosine Base EX", "Oil Black BS", "Oil Black SO", "Bontron N-01", "Bontron N-04", "Bontron N-07", "Bontron N-09", "Bontron N-11" (manufactured by Orient Chemical Industries, Ltd.); triphenylmethane dyes containing a tertiary amine in the side chain; quaternary ammonium salt compounds such as "Bontron P-51" (manufactured by Orient Chemical Industries, Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant); polyamine resins such as "AFP-B" (manufactured by Orient Chemical Industries, Ltd.); imidazole derivatives such as "PLZ-2001", "PLZ-8001" (manufactured by Shikoku Kasei Kogyo Co., Ltd.); styrene-acrylic resins such as "FCA-701PT", "FCA-201-PS" (manufactured by Fujikura Kasei Co., Ltd.).

[0091] In addition, examples of the negatively chargeable charge control agent include metal-containing azo dyes such as "Vari Fast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", "Bontron S-36" (manufactured by Orient Chemical Industries, Ltd.), "Eisen Spilon Black TRH", "T-77" (manufactured by Hodogaya Chemical Co., Ltd.), etc.; metal compounds of benzoic acid compounds such as "LR-147", "LR-297" (manufactured by Nippon Carlit Co., Ltd.), etc.; metal compounds of salicylic acid compounds such as "Bontron E-81", "Bontron E-84", "Bontron E-88", "Bontron E-304" (manufactured by Orient Chemical Industries, Ltd.), "TN-105" (manufactured by Hodogaya Chemical Co., Ltd.), etc.; copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE NX VP434" (manufactured by Clariant), nitroimidazole derivatives, etc.; and organometallic compounds, etc.

[0092] From the viewpoint of the charge stability of the toner, the content of the charge control agent is preferably 0.01 part by mass or more, more preferably 0.2 part by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less, based on 100 parts by mass of the binder resin.

[0093] The toner may be a toner obtained by any conventionally known method such as a melt kneading method, an emulsion aggregation method, a suspension polymerization method, etc., or may be a toner having a core-shell structure. However, from the viewpoint of smear property, a pulverized toner by a melt kneading method is preferred. In the case of a pulverized toner by a melt kneading method, it is preferably manufactured by a method including at least a step of melt kneading a binder resin and a colorant and a step of pulverizing the obtained kneaded product. For example, after uniformly mixing raw materials such as an amorphous polyester resin A, a colorant, and, if necessary, a crystalline polyester resin, a release agent, a charge control agent, etc. with a mixer such as a Henschel mixer, it is melt kneaded with a closed kneader, a single-screw or twin-screw extruder, an open roll type kneader, etc., and then cooled, pulverized, and classified.

[0094] In the toner of the present invention, it is preferable to use an external additive in order to improve transferability. Examples of the external additive include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide, and zinc oxide, and organic fine particles such as melamine resin fine particles and polytetrafluoroethylene resin fine particles, and two or more kinds may be used in combination. Among these, silica is preferable, and from the viewpoint of the transferability of the toner, hydrophobic silica that has been hydrophobized is more preferable.

[0095] Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), cyclic silazane, silicone oil, aminosilane, octyltriethoxysilane (OTES), and methyltriethoxysilane.

[0096] From the viewpoints of the chargeability, fluidity, and transferability of the toner, the average particle diameter of the external additive is preferably 5 nm or more, more preferably 10 nm or more, still more preferably 15 nm or more, and preferably 250 nm or less, more preferably 200 nm or less, still more preferably 90 nm or less.

[0097] The external addition treatment by mixing toner particles and the external additive can be performed according to a conventional method, and a mixer such as a Henschel mixer can be used.

[0098] From the viewpoints of the chargeability, fluidity, and transferability of the toner, the content of the external additive is preferably 0.05 part by mass or more, more preferably 0.1 part by mass or more, still more preferably 0.3 part by mass or more, and preferably 5 parts by mass or less, more preferably 3 parts by mass or less, based on 100 parts by mass of the toner particles before being treated with the external additive.

[0099] The volume median particle diameter (D 50 ) of the toner of the present invention is preferably 3 μm or more, more preferably 4 μm or more, and preferably 15 μm or less, more preferably 10 μm or less. In this specification, the volume median particle diameter (D 50The volume median diameter means the particle diameter at which the cumulative volume frequency calculated by volume fraction reaches 50% when calculated from the smaller particle diameters. When the toner is treated with an external additive, the volume median diameter of the toner particles before treatment with the external additive is defined as the volume median diameter of the toner.

[0100] The toner of the present invention can be used in an image forming apparatus using a one-component development system or a two-component development system, either as a one-component development toner as it is or as a two-component development toner used by mixing with a carrier.

Examples

[0101] Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited by these examples. Physical properties such as those of resins can be measured by the following methods.

[0102] 〔IV value of PET〕 It is dissolved in a mixed solvent of phenol / tetrachloroethane at a ratio of 60 / 40 (mass ratio) at a concentration of 4 g / L, and measured with an Ubbelohde viscometer, and calculated from the following formula. IV = (-1 + √(1 + 4kη)) / (2kC) 〔In the formula, k = 0.33, C = 0.004 g / mL, and η = (t 1 / t 0 ) - 1 (t 0 : dropping seconds of the solvent only, t 1 : dropping seconds of the sample solution).〕

[0103] 〔Softening point of resin〕 Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating 1 g of the sample at a heating rate of 6 °C / min, a load of 1.96 MPa is applied by a plunger and extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. The plunger descent amount of the flow tester is plotted against the temperature, and the temperature at which half of the sample has flowed out is defined as the softening point.

[0104] 〔Maximum peak temperature of endotherm of resin〕 Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 - 0.02 g of the sample into an aluminum pan, cool it from room temperature (25°C) to 0°C at a cooling rate of 10°C / min, and maintain it at 0°C for 1 minute. Then, measure it at a heating rate of 10°C / min. Among the observed endothermic peaks, the temperature of the peak with the largest peak area is defined as the maximum peak temperature of endotherm. For a crystalline resin, the maximum peak temperature of endotherm is defined as the melting point.

[0105] 〔Glass transition temperature of resin〕 Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 - 0.02 g of the sample into an aluminum pan, heat it up to 200°C, and then cool it from that temperature to 0°C at a cooling rate of 10°C / min. Next, heat the sample at a heating rate of 10°C / min and measure the endothermic peak. The temperature of the intersection of the extension line of the baseline below the maximum peak temperature of endotherm and the tangent line indicating the maximum slope from the rising part of the peak to the apex of the peak is defined as the glass transition temperature.

[0106] 〔Acid value of resin〕 Measure based on the method of JIS K 0070:1992. However, only change the measurement solvent from the mixed solvent of ethanol and ether specified in JIS K 0070 to a mixed solvent of acetone and toluene (acetone:toluene = 1:1 (volume ratio)) for an amorphous resin and a mixed solvent of chloroform and dimethylformamide (chloroform:dimethylformamide = 7:3 (volume ratio)) for a crystalline resin, respectively.

[0107] 〔Melting point of release agent〕 Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.02 g of the sample into an aluminum pan, heat it up to 200°C, and then cool it from 200°C to 0°C at a cooling rate of 10°C / min. Then, heat the sample at a heating rate of 10°C / min, measure the heat quantity, and define the maximum peak temperature of endotherm as the melting point.

[0108] 〔Volume median particle diameter and CV value of resin particles, colorant particles, and release agent particles〕 (1) Measuring device: Laser diffraction particle size analyzer "LA-920" (manufactured by Horiba, Ltd.) (2) Measurement conditions: Take the sample dispersion in the measurement cell, add distilled water, and measure the volume median particle size (D 50 ) and volume average particle size at a temperature where the absorbance is within the appropriate range. Also, the CV value is calculated according to the following formula. CV value (%) = (standard deviation of particle size distribution / volume average particle size) × 100

[0109] 〔Solid content concentration of resin dispersion, colorant dispersion, and release agent dispersion〕 Using an infrared moisture meter "FD-230" (manufactured by Kett Scientific Co., Ltd.), dry 5 g of the measurement sample under the conditions of a drying temperature of 150 °C and a measurement mode of 96 (monitoring time 2.5 minutes, fluctuation range 0.05%) to measure the moisture content (mass %) of the dispersion. The solid content concentration is calculated according to the following formula. Solid content concentration (mass %) = 100 - moisture content (mass %)

[0110] 〔Volume median particle size of aggregated particles〕 · Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) · Aperture diameter: 50 μm · Analysis software: "Multisizer (registered trademark) III version 3.51" (manufactured by Beckman Coulter, Inc.) · Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) · Measurement conditions: By adding the sample dispersion to 100 mL of the above electrolyte, adjust the concentration to a level where the particle sizes of 30,000 particles can be measured in 20 seconds, then measure 30,000 particles, and obtain the volume median particle size (D 50 ) from the particle size distribution.

[0111] 〔Average particle size of external additives〕 The average particle size refers to the number average particle size. Measure the particle sizes (average value of the major axis and minor axis) of 500 particles from a scanning electron microscope (SEM) photograph, and take their number average value.

[0112] 〔Volume median particle size (D of toner50 )〕 · Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) · Aperture diameter: 50 μm · Analysis software: "Multisizer (registered trademark) III Version 3.51" (manufactured by Beckman Coulter, Inc.) · Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) · Dispersion liquid: Prepared by dissolving polyoxyethylene lauryl ether "Emulgen (registered trademark) 109P" [manufactured by Kao Corporation, HLB (Griffin) = 13.6] in the electrolyte to adjust to 5% by mass · Dispersion conditions: Add 10 mg of the measurement sample to 5 mL of the above dispersion liquid, disperse for 1 minute with an ultrasonic disperser (machine name: US-1 manufactured by SND Co., Ltd., output: 80 W), then add 25 mL of the electrolyte, and further disperse for 1 minute with the ultrasonic disperser to prepare a sample dispersion liquid. · Measurement conditions: By adding the above sample dispersion liquid to 100 mL of the electrolyte, adjust to a concentration at which the particle size of 30,000 particles can be measured in 20 seconds, then measure 30,000 particles, and determine the volume median diameter (D 50 ) from the particle size distribution.

[0113] 〔Roundness of toner〕 Measure the roundness of toner particles under the following conditions. · Measuring device: Flow-type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) · Preparation of dispersion liquid: Prepare by diluting the dispersion liquid of toner particles with deionized water so that the solid content concentration becomes 0.001 to 0.05% by mass. · Measurement mode: HPF measurement mode

[0114] Resin production example 1 An alcohol component, a carboxylic acid component other than trimellitic anhydride, PET, an esterification catalyst, and a cocatalyst shown in Tables 1 to 3 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downward-flow condenser having a water removal tube, a stirrer, and a thermocouple. After heating to 235°C under a nitrogen atmosphere, polycondensation was carried out at 235°C for 6 hours. Then, the temperature was lowered to 210°C, trimellitic anhydride shown in Tables 1 to 3 was added, and after reacting at 210°C for 1 hour, the reaction was further carried out at 210°C under a reduced pressure of 10 kPa until the softening point described in the table was reached, to obtain an amorphous polyester resin (resins AH1 to AH8, AH13 to AH16). The physical properties are shown in Tables 1 to 3.

[0115] Resin Production Example 2 An alcohol component, a carboxylic acid component, PET, an esterification catalyst, and a cocatalyst shown in Tables 2 and 5 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downward-flow condenser having a water removal tube, a stirrer, and a thermocouple. After maintaining the temperature at 180°C for 1 hour under a nitrogen atmosphere, the temperature was raised from 180°C to 235°C at 10°C / h, and further polycondensation was carried out at 235°C for 5 hours. Then, the temperature was lowered to 210°C and the reaction was carried out under a reduced pressure of 10 kPa until the softening point described in the table was reached, to obtain an amorphous polyester resin (resin AH9, resin AL9). The physical properties are shown in Tables 2 and 5.

[0116] Resin Production Example 3 An alcohol component, a carboxylic acid component other than trimellitic anhydride, PET, an esterification catalyst, and a cocatalyst shown in Table 2 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downward-flow condenser having a water removal tube, a stirrer, and a thermocouple. After heating to 235°C under a nitrogen atmosphere, polycondensation was carried out at 235°C for 10 hours. Then, the temperature was lowered to 210°C, trimellitic anhydride shown in Table 2 was added, and after reacting at 210°C for 1 hour, the reaction was further carried out at 210°C under a reduced pressure of 10 kPa until the softening point described in Table 2 was reached, to obtain an amorphous polyester resin (resin AH10). The physical properties are shown in Table 2.

[0117] Resin Production Example 4 The alcohol component, carboxylic acid component other than trimellitic anhydride, esterification catalyst, and cocatalyst shown in Table 2 were placed in a 5-liter four-necked flask equipped with a nitrogen inlet tube, a dehydration tube equipped with a fractionating tube through which hot water at 98 °C passed, a stirrer, and a thermocouple. After holding at 180 °C for 1 hour under a nitrogen atmosphere, the temperature was raised from 180 °C to 235 °C at 10 °C / h, and then polycondensation was carried out at 235 °C for 5 hours. Thereafter, the temperature was lowered to 210 °C, the trimellitic anhydride shown in Table 2 was added, and after reacting at 210 °C for 1 hour, the reaction was further carried out at 210 °C under a reduced pressure of 10 kPa until the softening point shown in Table 2 was reached, to obtain an amorphous polyester resin (resin AH11). The physical properties are shown in Table 2.

[0118] Resin Production Example 5 The alcohol component, carboxylic acid component other than trimellitic anhydride, esterification catalyst, and cocatalyst shown in Table 2 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downflow condenser having a dehydration tube, a stirrer, and a thermocouple. After raising the temperature to 235 °C under a nitrogen atmosphere, polycondensation was carried out at 235 °C for 6 hours. Thereafter, the temperature was lowered to 210 °C, the trimellitic anhydride shown in Table 2 was added, and after reacting at 210 °C for 1 hour, the reaction was further carried out at 210 °C under a reduced pressure of 10 kPa until the softening point shown in Table 2 was reached, to obtain an amorphous polyester resin (resin AH12). The physical properties are shown in Table 2.

[0119] Resin Production Example 6 The alcohol component, carboxylic acid component, PET, esterification catalyst, and cocatalyst shown in Tables 4 to 6 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downflow condenser having a dehydration tube, a stirrer, and a thermocouple. After raising the temperature to 235 °C under a nitrogen atmosphere, polycondensation was carried out at 235 °C for 6 hours. Thereafter, the temperature was lowered to 210 °C, and the reaction was carried out under a reduced pressure of 10 kPa until the softening point described in Tables 4 to 6 was reached, to obtain amorphous polyester resins (resins AL1 to AL8, AL13 to AL16). The physical properties are shown in Tables 4 to 6.

[0120] Resin Production Example 7 The alcohol component, carboxylic acid component, PET, esterification catalyst, and cocatalyst shown in Table 5 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downflow condenser having a water removal tube, a stirrer, and a thermocouple. After heating to 235°C under a nitrogen atmosphere, polycondensation was carried out at 235°C for 10 hours. Then, the temperature was lowered to 210°C, and the reaction was carried out under a reduced pressure of 10 kPa until the softening point described in Table 5 was reached to obtain an amorphous polyester resin (resin AL10). The physical properties are shown in Table 5.

[0121] Resin Production Example 8 The alcohol component, carboxylic acid component, esterification catalyst, and cocatalyst shown in Table 5 were placed in a 5-liter four-necked flask equipped with a nitrogen inlet tube, a water removal tube equipped with a fractionating tube through which 98°C hot water passed, a stirrer, and a thermocouple. After holding at 180°C for 1 hour under a nitrogen atmosphere, the temperature was raised from 180°C to 235°C at 10°C / h, and then polycondensation was carried out at 235°C for 5 hours. Then, the temperature was lowered to 210°C, and the reaction was carried out under a reduced pressure of 10 kPa until the softening point described in Table 5 was reached to obtain an amorphous polyester resin (resin AL11). The physical properties are shown in Table 5.

[0122] Resin Production Example 9 The alcohol component, carboxylic acid component, esterification catalyst, and cocatalyst shown in Table 5 were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a downflow condenser having a water removal tube, a stirrer, and a thermocouple. After heating to 235°C under a nitrogen atmosphere, polycondensation was carried out at 235°C for 6 hours. Then, the temperature was lowered to 210°C, and the reaction was carried out under a reduced pressure of 10 kPa until the softening point described in Table 5 was reached to obtain an amorphous polyester resin (resin AL12). The physical properties are shown in Table 5.

[0123]

Table 1

[0124]

Table 2

[0125]

Table 3

[0126]

Table 4

[0127]

Table 5

[0128]

Table 6

[0129] Production Example 10 of Resin The alcohol component and carboxylic acid component shown in Table 7 were placed in a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a downward condenser having a dehydrating tube, and a nitrogen inlet tube, and heated in a mantle heater in a nitrogen atmosphere to 200 °C over 8 hours. Then, the esterification catalyst shown in Table 7 was added, and the reaction was carried out at 8.0 kPa until the softening point shown in Table 7 was reached to obtain a crystalline polyester resin (Resin C1). The physical properties are shown in Table 7.

[0130]

Table 7

[0131] Examples 1 to 6, 8 to 11, 14 to 18, and Comparative Examples 2 and 3 [Melt Kneading Method] 100 parts by mass of the binder resin shown in Table 8, 5 parts by mass of the colorant "Toner Yellow HG" (manufactured by Clariant, C.I. Pigment Yellow 180), 3 parts by mass of the release agent "Carnauba Wax C1" (manufactured by Kato Yoko Co., Ltd., melting point: 83 °C), and 0.5 part by mass of the negative charge control agent "Bontron E-304" (manufactured by Orient Chemical Industries, Ltd.) were mixed with a Henschel mixer.

[0132] The obtained mixture was melt-kneaded using a co-rotating twin-screw extruder with a total length of the kneading section of 1560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm at a screw rotation speed of 200 r / min and a barrel set temperature of 100 °C to obtain a melt-kneaded product. The supply rate of the mixture was 20 kg / h, and the average residence time was about 18 seconds.

[0133] After cooling and coarsely pulverizing the obtained melt-kneaded product, it was pulverized using a jet mill and classified using an air classifier (manufactured by Nippon Pneumatic Mfg. Co., Ltd.) to obtain toner particles with a volume median diameter (D 50 ) of 7.0 μm.

[0134] 100 parts by mass of the obtained toner particles, 1.0 part by mass of hydrophobic silica "R972" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle diameter: 16 nm), and 1.0 part by mass of hydrophobic silica "RY-50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: silicone oil, average particle diameter: 40 nm) as external additives were mixed using a Henschel mixer at a rotation speed of 3000 r / min (peripheral speed 32 m / sec) for 3 minutes to obtain a yellow toner.

[0135] Example 7 In Example 1, a yellow toner was obtained in the same manner as in Example 1, except that "Pario Tol Yellow D1155" (manufactured by Sankyo Chemical Co., Ltd., C.I. Pigment Yellow 185) was used instead of the colorant "Toner Yellow HG" (manufactured by Clariant, C.I. Pigment Yellow 180).

[0136] Comparative Example 1 In Example 1, a yellow toner was obtained in the same manner as in Example 1, except that "Toner Yellow 3GP-CT" (manufactured by Clariant, C.I. Pigment Yellow 155 (total number of -NH- groups and -NH 2 groups in one molecule = 2, molecular weight = 717, NH group amount = 2.8 mmol / g)) was used instead of the colorant "Toner Yellow HG" (manufactured by Clariant, C.I. Pigment Yellow 180).

[0137] Comparative Example 4 In Example 1, instead of the colorant "Toner Yellow HG" (manufactured by Clariant, C.I. Pigment Yellow 180), "HANSA Yellow 5GX01" (manufactured by Clariant, C.I. Pigment Yellow 74 (total number of -NH- groups and -NH 2 groups in one molecule = 1, molecular weight = 386, NH group amount = 2.6 mmol / g)) was used, and a yellow toner was obtained in the same manner as in Example 1.

[0138] Example 12 A yellow toner was obtained in the same manner as in Example 1, except that a continuous two-open-roll kneader "Neutex" (manufactured by Nippon Coke & Engineering Co., Ltd.) was used instead of the co-rotating twin-screw extruder during melt kneading. The continuous two-open-roll kneader had a roll outer diameter of 0.14 m and an effective roll length of 0.8 m. The operating conditions were as follows: the rotational speed of the high-speed roll (front roll) was 75 r / min (peripheral speed 33 m / min), the rotational speed of the low-speed roll (rear roll) was 50 r / min (peripheral speed 22 m / min), and the roll gap was 0.1 mm. The temperature of the heating and cooling medium inside the roll was set such that the temperature at the raw material input side of the high-speed roll was 140°C and the temperature at the kneaded product discharge side was 110°C, and the temperature at the raw material input side of the low-speed roll was 65°C and the temperature at the kneaded product discharge side was 30°C. Also, the supply rate of the raw material mixture was 10 kg / h, and the average residence time was about 5 minutes.

[0139] Example 13 [Emulsion Aggregation Method] <Preparation of Aqueous Dispersion of Core Resin Particles> 600 g of methyl ethyl ketone was charged into a 5-liter container equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube. 129 g of resin AH1 and 21 g of resin C1 were added and dissolved at 60°C. To the resulting solution, a 5% by mass aqueous sodium hydroxide solution was added to a neutralization degree of 60 mol% with respect to the acid value of the resin, and the mixture was stirred for 30 minutes to obtain a mixture. Subsequently, 675 g of deionized water was added over 77 minutes. Then, while stirring at 250 r / min, methyl ethyl ketone was distilled off under reduced pressure at a temperature of 50°C or lower, and the solid content concentration of the aqueous dispersion was measured. The solid content concentration of the aqueous dispersion was adjusted to 20% by mass with deionized water to obtain a core resin dispersion. The volume median diameter (D 50 ) of the resin particles in the dispersion was 200 nm, and the CV value was 24%.

[0140] <Preparation of Aqueous Dispersion of Shell Resin Particles> 600 g of methyl ethyl ketone was charged into a 5-liter container equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube. 150 g of resin AL1 was added and dissolved at 60°C. To the resulting solution, a 5% by mass aqueous sodium hydroxide solution was added to a neutralization degree of 60 mol% with respect to the acid value of the resin, and the mixture was stirred for 30 minutes to obtain a mixture. Subsequently, 675 g of deionized water was added over 77 minutes. Then, while stirring at 250 r / min, methyl ethyl ketone and a part of water were distilled off under reduced pressure at a temperature of 50°C or lower, and the solid content concentration of the aqueous dispersion was measured. The solid content concentration of the aqueous dispersion was adjusted to 20% by mass with deionized water to obtain a shell resin dispersion. The volume median diameter (D 50 ) of the resin particles in the dispersion was 130 nm, and the CV value was 22%.

[0141] <Preparation of Colorant Dispersion> In a 1-liter beaker, 116.2 g of the colorant "Toner Yellow HG" (manufactured by Clariant, C.I. Pigment Yellow 180), 154.9 g of the anionic surfactant "Neoperex (registered trademark) G-15" (manufactured by Kao Corporation, 15% by mass aqueous solution of sodium dodecylbenzenesulfonate), and 260 g of deionized water were mixed and dispersed at room temperature for 3 hours using a homogenizer. Then, deionized water was added so that the solid content concentration became 24% by mass, thereby obtaining a colorant dispersion. The volume median particle size (D 50 ) of the colorant particles in the dispersion was 140 nm, and the CV value was 28%.

[0142] <Preparation of release agent dispersion> 50 g of Fischer-Tropsch wax (manufactured by Nippon Seiro Co., Ltd., trade name: FNP0090, melting point: 90°C), 5 g of a cationic surfactant (manufactured by Kao Corporation, trade name: Sanisol B50), and 200 g of deionized water were heated to 95°C, and the wax was dispersed using a homogenizer. Then, it was subjected to a dispersion treatment with a pressure discharge type homogenizer to obtain a release agent dispersion with a solid content concentration of 20% by mass. The volume median particle size (D 50 ) of the release agent particles in the dispersion was 550 nm, and the CV value was 26%.

[0143] <Preparation of toner particles> In a 3-liter four-necked flask equipped with a reflux condenser, a stirring device, and a thermocouple, 500 g of the core resin dispersion, 36 g of the colorant dispersion, 33 g of the release agent dispersion, and 3.3 g of a 15% by mass aqueous solution of sodium dodecylbenzenesulfonate "Neoperex G-15" (manufactured by Kao Corporation, anionic surfactant) were mixed at a temperature of 25°C. Next, while stirring the obtained mixture, an aqueous solution prepared by dissolving 40 g of ammonium sulfate in 570 g of deionized water and adding a 4.8% by mass aqueous solution of potassium hydroxide to adjust the pH to 8.2 was added dropwise over 10 minutes at 25°C. Then, the temperature was raised to 62°C over 2 hours, and the mixture was held at 62°C until the volume median particle size (D 50 ) of the aggregated particles reached 7.1 μm, thereby obtaining a dispersion of aggregated particles (I).

[0144] While maintaining the temperature of the dispersion of the obtained aggregated particles (I) at 62°C, 215 g of the resin dispersion for the shell was dropped at a rate of 0.6 mL / min (0.6 g / min) to obtain a dispersion of aggregated particles (II). The volume median diameter (D 50 ) of the aggregated particles (II) was 7.0 μm.

[0145] To the obtained dispersion of aggregated particles (II), an aqueous solution obtained by mixing 20 g of sodium polyoxyethylene lauryl ether sulfate "Emal E-27C" (manufactured by Kao Corporation, anionic surfactant, effective concentration 27% by mass), 280 g of deionized water, and 40 g of a 0.1 mol / L sulfuric acid aqueous solution was added. Then, the temperature was raised to 80°C over 1 hour, held at 80°C for 30 minutes, 10 g of a 0.1 mol / L sulfuric acid aqueous solution was added, and it was further held at 80°C for 15 minutes. Then, 15 g of a 0.1 mol / L sulfuric acid aqueous solution was added again, and by holding at 80°C until the circularity reached 0.970, a dispersion of fused particles (core-shell particles) in which the aggregated particles were fused was obtained.

[0146] The obtained core-shell particle dispersion was cooled to 30°C, the dispersion was suction filtered to separate the solid content, then washed with deionized water at 25°C, and suction filtered at 25°C for 2 hours. Then, using a vacuum isothermal dryer "DRV622DA" (manufactured by ADVANTEC), vacuum drying was performed at 33°C for 24 hours to obtain toner particles. The volume median diameter (D 50 ) of the obtained toner particles was 7.0 μm, and the circularity was 0.970. The composition ratio (mass ratio) of the binder resin of the obtained toner particles was resin AH1 / resin AL1 / resin C1 = 60 / 30 / 10.

[0147] 100 parts by mass of the obtained toner particles and, as an external additive, 1.0 part by mass of hydrophobic silica "R972" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle diameter: 16 nm) and 1.0 part by mass of hydrophobic silica "RY-50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: silicone oil, average particle diameter: 40 nm) were mixed in a Henschel mixer at a rotational speed of 3000 r / min (peripheral speed 32 m / sec) for 3 minutes to obtain a yellow toner.

[0148] Test Example [Smear Property of Printed Matter] Toner was installed in a copying machine "AR-505" (trade name, manufactured by Sharp Corporation), and a solid image was taken out before passing through the fixing unit to obtain a printed matter in an unfixed state (print area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm 2 ). Further, the unfixed image was printed twice on the same paper, and the adhesion amount was 1.5 mg / cm 2 . The unfixed image thus obtained was fixed at 150 °C and 300 mm / s to obtain a printed matter.

[0149] A stainless-steel weight with a length of 3 cm, a width of 3 cm, a height of 6.5 cm, and a weight of 500 g was placed on the obtained printed matter, and it was reciprocated on the printed area at a speed of 0.5 m / s. One reciprocation was regarded as one time, and the upper limit was 50 times. The number of times the black band-shaped toner deposits appeared in the non-printing area was visually confirmed to evaluate the smear property. The results are shown in Table 8. The larger the number of times, the better the smear property. In the table, ">50" indicates that toner deposits could not be confirmed even after 50 times.

[0150]

Table 8

[0151] From the above results, it can be seen that the toners of Examples 1 to 18 have good smear properties compared with the toners of Comparative Examples 1 and 4 containing organic yellow pigments with a small amount of NH groups, and the toners of Comparative Examples 2 and 3 that do not use PET. In particular, it can be seen from Comparative Example 2 that using ethylene glycol and terephthalic acid, which are monomer components of PET, has no effect, and it is important to use PET.

Industrial Applicability

[0152] The toner for electrostatic charge image development of the present invention is suitably used for developing latent images formed in electrophotography, electrostatic recording, electrostatic printing, etc.

Claims

1. A toner for developing an electrostatic image, comprising a binder resin and a colorant, the binder resin comprising an amorphous polyester resin A which is a polycondensation product of polyethylene terephthalate, an alcohol component and a carboxylic acid component, the colorant comprising an -NH- group and an -NH ２ The toner for developing electrostatic images contains an organic yellow pigment having an NH group amount of 4.0 mmol / g or more and 15.0 mmol / g or less, where the NH group amount is the total number of groups divided by the molecular weight.

2. 2. The toner for developing electrostatic images according to claim 1, wherein the content of polyethylene terephthalate is 5 mol % or more and 75 mol % or less of the total amount of the alcohol component, the carboxylic acid component and the polyethylene terephthalate, assuming that a terephthalic acid-ethylene glycol unit is 1 mol.

3. 2. The toner for developing electrostatic images according to claim 1, wherein the content of polyethylene terephthalate is 10 mol % or more and 50 mol % or less of the total amount of the alcohol component, the carboxylic acid component and the polyethylene terephthalate, assuming that a terephthalic acid-ethylene glycol unit is 1 mol.

4. 4. The toner for developing electrostatic images according to claim 1, wherein the IV value of the polyethylene terephthalate is from 0.40 to 0.

85.

5. 4. The toner for developing electrostatic images according to claim 1, wherein the organic yellow pigment is at least one selected from the group consisting of benzimidazolone pigments, isoindoline pigments, and condensed disazo pigments.

6. The toner for developing electrostatic images according to any one of claims 1 to 3, wherein the organic yellow pigment is at least one selected from the group consisting of C. I. Pigment Yellow 180 and C. I. Pigment Yellow 185.

7. 4. The toner for developing electrostatic images according to claim 1, wherein the amorphous polyester resin A has an ester group concentration of 3.5 mmol / g or more and 12.0 mmol / g or less.

8. 4. The toner for developing electrostatic images according to claim 1, wherein the content of the organic yellow pigment is from 1 part by mass to 20 parts by mass based on 100 parts by mass of the amorphous polyester resin A.

9. 4. The toner for developing electrostatic images according to claim 1, wherein the binder resin further contains a crystalline polyester resin C.

10. 4. The toner for developing electrostatic images according to claim 1, wherein the amorphous polyester resin A contains resins having different softening points with a difference of 10° C. or more.

11. 4. The method for producing a toner for developing an electrostatic image according to claim 1, further comprising the steps of melting and kneading at least the binder resin and the colorant, and pulverizing the resulting kneaded mixture.