JP2011247942A - Toner and method for manufacturing the same, developer, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner which is excellent in releasability even upon low temperature fixing and can suppress scattering of powder dust, a method for producing the same, a developer using the toner, and an image forming method using the developer.SOLUTION: The toner includes base particles which contain a binding resin, a colorant, a paraffin wax, a microcrystalline wax and inorganic particles. A mass ratio of the paraffin wax to the total mass of the paraffin wax and microcrystalline wax is between 5% and 15%.

Description

  The present invention relates to a toner, a toner manufacturing method, a developer, and an image forming method.

  Image formation by electrophotography generally forms an electrostatic latent image on a photoreceptor, develops the electrostatic latent image with a developer to form a toner image, and then transfers the toner image to a recording medium such as paper. Then, the toner image transferred to the recording medium is fixed.

  In recent years, electrophotography is used for printing as pre-production printing, and ultra-high speed machines exceeding 60 sheets / minute are known.

  Since office equipment such as image forming apparatuses are usually installed indoors, the German Blue Angel (RAL-UZ62, 85, 114) defines the dust emitted from office equipment such as image forming apparatuses. Has been.

  On the other hand, a method of adding wax to toner when fixing a toner image using an oilless type heat roll is known.

  However, there has been a problem that the releasability at the time of low-temperature fixing is insufficient.

  Therefore, in Patent Document 1, an organic solvent phase obtained by dissolving or dispersing a binder resin or its precursor polymer, colorant, wax and inorganic fine particles in an organic solvent is emulsified or dispersed in an aqueous medium. Thereafter, a toner obtained through a step of removing the organic solvent is disclosed. At this time, the toner contains inorganic fine particles whose surface is hydrophobized and a wax having a melting point of 50 to 90 ° C. and constituting a molecular chain only by C—H and C—C bonds.

  However, there is a problem that dust is diffused during image formation. At this time, if a wax having a high melting point is used in order to suppress dust dispersion, there is a problem that the releasability at the time of low-temperature fixing becomes insufficient in an ultra-high speed machine.

  SUMMARY OF THE INVENTION In view of the above-described problems of the prior art, the present invention provides a toner that is excellent in releasability during low-temperature fixing and can suppress dust emission, a method for producing the toner, a developer having the toner, and the development. An object of the present invention is to provide an image forming method using an agent.

  The invention described in claim 1 is a toner having base particles including a binder resin, a colorant, paraffin wax, microcrystalline wax and inorganic particles, wherein the paraffin with respect to a total mass of the paraffin wax and the microcrystalline wax. The ratio of the mass of the wax is 5% or more and 15% or less.

  According to a second aspect of the present invention, in the toner according to the first aspect, the paraffin wax has a melting point of 65 ° C. or higher and 85 ° C. or lower.

  According to a third aspect of the present invention, in the toner according to the first or second aspect, the microcrystalline wax has a melting point of 60 ° C. or higher and 90 ° C. or lower.

  According to a fourth aspect of the present invention, in the toner according to any one of the first to third aspects, the microcrystalline wax has a mass loss at 165 ° C. of 10% or less.

  According to a fifth aspect of the present invention, in the toner according to any one of the first to fourth aspects, the total content of the paraffin wax and the microcrystalline wax is 2% by mass or more and 10% by mass or less. Features.

  According to a sixth aspect of the present invention, in the toner according to any one of the first to fifth aspects, the inorganic particles are hydrophobized silica.

  According to a seventh aspect of the present invention, in the toner according to any one of the first to sixth aspects, the average circularity is 0.94 or more and 0.98 or less.

  According to an eighth aspect of the present invention, in the toner according to any one of the first to seventh aspects, the volume average particle size is 3 μm or more and 8 μm or less, and the content of components having a particle size of 25 μm or more is 0.00. It is characterized by being 5% by mass or less.

  According to a ninth aspect of the invention, in the toner according to any one of the first to eighth aspects, the binder resin contains a urea-modified polyester.

  According to a tenth aspect of the present invention, in the toner according to the ninth aspect, the binder resin further includes a polyester.

  According to an eleventh aspect of the present invention, in the toner according to any one of the first to tenth aspects, the binder resin further includes a polyester.

  According to a twelfth aspect of the present invention, in the method for producing a toner, a toner material containing a polyester prepolymer having an isocyanate group, a compound having an amino group, a colorant, paraffin wax, microcrystalline wax and inorganic particles is contained in an organic solvent. A step of preparing a first liquid by dissolving or dispersing; a step of preparing a second liquid by emulsifying or dispersing the first liquid in an aqueous medium containing resin particles; and the second liquid. And the ratio of the mass of the paraffin wax to the total mass of the paraffin wax and the microcrystalline wax is 5% or more and 15% or less.

  According to a thirteenth aspect of the present invention, in the toner manufacturing method according to the twelfth aspect, the toner material further includes polyester.

  According to a fourteenth aspect of the present invention, in the toner manufacturing method according to the thirteenth aspect, the ratio of the mass of the polyester prepolymer to the total mass of the polyester and the polyester prepolymer is 5% or more and 25% or less. It is characterized by.

  According to a fifteenth aspect of the present invention, the developer includes the toner according to any one of the first to eleventh aspects.

  According to a sixteenth aspect of the present invention, in the image forming method, the step of charging the photoconductor, the step of exposing the charged photoconductor to form an electrostatic latent image, and the electrostatic formed on the photoconductor A step of developing a latent image with the developer according to claim 15 to form a toner image, a step of transferring a toner image formed on the photoreceptor to a recording medium, and a toner image transferred to the recording medium It has the process of fixing.

  According to the present invention, there are provided a toner excellent in releasability at low-temperature fixing and capable of suppressing dust dispersion, a method for producing the toner, a developer having the toner, and an image forming method using the developer. Can be provided.

It is a figure which shows the measuring apparatus of a separation resistance force.

  Next, the form for implementing this invention is demonstrated.

  The toner of the present invention has base particles including a binder resin, a colorant, paraffin wax, microcrystalline wax and inorganic particles, and the ratio of the mass of paraffin wax to the total mass of paraffin wax and microcrystalline wax is 5 to 15. %. In the toner of the present invention, since the inorganic particles are contained in the base particles, the inorganic particles are hardly detached and the amount of the fluidity improver added can be reduced. As a result, the toner of the present invention can efficiently bring out the effect of wax and is excellent in releasability at low temperature fixing. In the toner of the present invention, since the ratio of the mass of the paraffin wax to the total mass of the paraffin wax and the microcrystalline wax is 5 to 15%, generation of dust can be suppressed.

  When the ratio of the mass of the paraffin wax to the total mass of the paraffin wax and the microcrystalline wax is less than 5%, the releasability at low temperature fixing is lowered, and when it exceeds 15%, dust is emitted.

  The paraffin wax preferably has a melting point of 65 to 85 ° C. If the melting point of the paraffin wax is less than 65 ° C., the heat-resistant storage stability of the toner may be lowered, and if it exceeds 85 ° C., the low-temperature fixability of the toner may be lowered.

  The microcrystalline wax preferably has a melting point of 60 to 90 ° C. When the melting point of the microcrystalline wax is less than 60 ° C., the blocking resistance of the toner may be lowered, and when it exceeds 90 ° C., the productivity may be lowered.

  The melting point of the wax can be measured using TA-60WS and DSC-60 (manufactured by Shimadzu Corporation).

  The microcrystalline wax preferably has a mass loss at 165 ° C. of 10% or less. When the mass loss of the microcrystalline wax at 165 ° C. exceeds 10%, dust may be emitted.

In addition, the mass reduction | decrease in 165 degreeC of wax can be measured using TA-60WS and DTG-60 (made by Shimadzu Corp.). At this time, the mass decrease at 165 ° C. is expressed by the equation (AB) / A × 100, where A is the mass of the wax when reaching 165 ° C. and B is the weight of the wax when held at 165 ° C. for 60 minutes.
It is represented by

  The total content of paraffin wax and microcrystalline wax in the toner is preferably 2 to 10% by mass. If the total content of paraffin wax and microcrystalline wax in the toner is less than 2% by mass, the releasability of the toner may be reduced, and if it exceeds 10% by mass, the fluidity of the toner may be reduced. is there.

  The inorganic particles are not particularly limited, but silicon dioxide (silica), titanium dioxide (titania), aluminum oxide (alumina), iron oxide, copper oxide, zinc oxide, tin oxide, antimony trioxide, magnesium oxide, zirconium oxide, Metal oxides such as chromium oxide and cerium oxide; metal titanates such as barium titanate, magnesium titanate, calcium titanate and strontium titanate; metal sulfates such as barium sulfate; metal carbonates such as barium carbonate and calcium carbonate Salts: nitrides such as silicon nitride; silica sand, clay, mica, wollastonite, diatomaceous earth and the like may be mentioned, and two or more kinds may be used in combination. Among these, metal oxides are preferable, silicon dioxide (silica), titanium dioxide (titania), and aluminum oxide are more preferable. It is difficult to move from an organic solvent into an aqueous medium, and dispersibility in the organic solvent is good. Silicon dioxide (silica) is particularly preferred.

  The inorganic particles are preferably hydrophobized. Thereby, since the hydrophilic group which exists on the surface of an inorganic particle is substituted by the hydrophobic group (lipophilic group), an inorganic particle becomes hydrophobic (lipophilic).

  The degree of hydrophobicity of the inorganic particles subjected to the hydrophobization treatment is usually 5 to 90% by mass, preferably 10 to 90% by mass, and more preferably 10 to 70% by mass. If the degree of hydrophobicity of the hydrophobized inorganic particles is less than 5%, the hydrophobized inorganic particles may easily move from the organic solvent into the aqueous medium. In some cases, inorganic particles that have been hydrophobized are likely to aggregate.

  At this time, the range of the degree of hydrophobicity of the inorganic particles is included in the base particles and is not easily affected by the environment. Therefore, the range of the degree of hydrophobicity of the inorganic particles when used as a fluidity improver should be wider. Can do.

  In addition, the degree of hydrophobicity of the inorganic particles that have been hydrophobized is confirmed by visual observation when a small amount of inorganic particles that have been hydrophobized is added to an aqueous methanol solution prepared in increments of 2.5% by mass. This is the minimum methanol concentration.

  The number average particle diameter of the inorganic particles is usually 5 to 200 nm, preferably 10 to 180 nm. If the number average particle diameter of the inorganic particles is less than 5 nm, the toner may easily aggregate, and if it exceeds 200 nm, the low-temperature fixability may be deteriorated.

  The number average particle size of the inorganic particles can be measured using a particle size distribution measuring device DLS-700 (manufactured by Otsuka Electronics Co., Ltd.), Coulter N4 (manufactured by Coulter Electronics Co., Ltd.) or the like using dynamic light scattering.

  In addition, the number average particle diameter of the inorganic particles subjected to the hydrophobization treatment is obtained by taking a photograph using a scanning electron microscope, a transmission electron microscope, etc., and averaging the long diameters of 100 or more inorganic particles. The average particle size can be measured.

  The ratio of the number average particle diameter of the toner to the number average particle diameter of the inorganic particles is usually from 5 to 2000, and preferably from 20 to 200. This makes it easy to control the particle size of the toner.

  The shape of the inorganic particles is not particularly limited, and examples thereof include a spherical shape, a linear shape, a mesh shape, and an indefinite shape, and two or more kinds of inorganic particles having different shapes may be used in combination.

  When inorganic particles are dispersed in an organic solvent, inorganic particles having different shapes may be obtained depending on the dispersion state.

  The method of hydrophobizing inorganic particles is not particularly limited, but the method of treating inorganic particles with a hydrophobizing agent, the method of treating inorganic particles with a hydrophobizing agent and an amine simultaneously, the inorganic particles with a hydrophobizing agent and an amine. Examples of the method include a stepwise treatment, a method of treating inorganic particles with a hydrophobizing agent, and then a treatment with an amine.

  The hydrophobizing agent is not particularly limited as long as the surface of the inorganic particles can be hydrophobized, but a silane coupling agent, a silylating agent, an organic titanate coupling agent, an aluminum coupling agent, silicone oil. Etc., and two or more of them may be used in combination. Among them, a compound having a silicon atom or a silicone compound is preferable, and a silane coupling agent is particularly preferable from the viewpoint of dispersion stability of inorganic particles in an organic solvent.

Although it does not specifically limit as a silane coupling agent, General formula Si (Q) x (P) y (A) z ... (1)
(In the formula, Q is a halogen group, an amino group or a hydrolyzable group, A is an alkyl group or an aryl group, and P is a general formula —XOOC (R) C═CH _2.
(In the formula, R is an alkyl group, and X is an alkylene group, an oxy group, an imino group, or a carbonylalkylene group.)
A functional group represented by the formula: -XNHR
(In the formula, R is an alkyl group or an aryl group, and X is an alkylene group, an oxy group, an imino group, or a carbonylalkylene group.)
Or a functional group represented by the general formula —XNH ₂
(In the formula, X represents an alkylene group, an oxy group, an imino group, or a carbonylalkylene group.)
X and y are each independently an integer of 1 or more, z is an integer of 0 or more, and the sum of x, y, and z is 4. )
The compound represented by these, the silane coupling agent which has a fluorinated alkyl group, a silazane, etc. are mentioned, You may use 2 or more types together. Among these, a compound represented by the general formula (1) and silazane are preferable.

  In the general formula (1), the hydrolyzable group is not particularly limited, and examples thereof include an alkoxy group. Although it does not specifically limit as a halogen group, A fluoro group, a chloro group, a bromo group, an iodo group etc. are mentioned. Although it does not specifically limit as an alkyl group, A methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, a pentyl group, a hexyl group, a cyclohexyl group etc. are mentioned. Although it does not specifically limit as an alkoxy group, A methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned. The aryl group is not particularly limited, and examples thereof include a benzyl group. Although it does not specifically limit as an alkylene group, A methylene group, ethylene group, a propylene group, etc. are mentioned.

  The alkyl group, alkoxy group, aryl group and alkylene group may be further substituted with a known substituent.

  Specific examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and 3-glycidoxypropyl. Trimethoxysilane (γ-glycidoxypropyltrimethoxysilane), 3-glycidoxypropylmethyldiethoxysilane (γ-glycidoxypropylmethyldimethoxysilane), 3-glycidoxypropyltriethoxysilane, p-styryl Trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane (γ-methacryloxypropyltrimethoxysilane), 3-methacryloxypropylmethyldiethoxysilane, 3- Tacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane (γ- (2-aminoethyl) aminopropylmethyldimethoxysilane), N- (2-aminoethyl) -3-aminopropyltrimethoxysilane (γ- (2-aminoethyl) aminopropyltrimethoxysilane], N- (2-aminoethyl) -3-aminopropyltriethoxysilane, 3-amino Propyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane (γ-anilinopropyl) Trimethoxysilane), N- (vinyl benzine) ) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride (N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane hydrochloride), octadecyldimethyl (3- (trimethoxysilyl) ) Propyl) ammonium chloride, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane (γ-mercaptopropyltrimethoxysilane), bis (tri Ethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, methyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, di Examples thereof include phenyldichlorosilane, trifluoropropyltrichlorosilane, heptadecafluorodecyltrichlorosilane, disilazane, and trisilazane, and two or more of them may be used in combination. Among these, disilazane is preferable, and hexamethyldisilazane is particularly preferable in that halogen atoms do not remain in the inorganic particles that have been subjected to the hydrophobization treatment and the dispersion stability in the organic solvent is excellent.

  The surface of inorganic particles that have been hydrophobized with a hydrophobizing agent is not completely hydrophobized, and some hydrophilic groups remain. Therefore, the inorganic particles hydrophobized with a hydrophobizing agent are further hydrophobized. It may be processed.

  The method for further hydrophobizing inorganic particles that have been hydrophobized with a hydrophobizing agent is not particularly limited, but it is possible to substitute hydroxyl groups present on the surface of the inorganic particles hydrophobized with a hydrophobizing agent. Examples thereof include a method using a possible organometallic compound, a method using an amine in combination, and the like. Among them, a method in which an amine, which is also known as an end capping agent for a silanol group, is used in combination from the viewpoint of good dispersibility of the inorganic particles in the base particles.

  The amine may be any of primary amine, secondary amine, tertiary amine, and quaternary amine, and may be any of monoamine, diamine, and triamine. Good. Of these, tertiary amines and quaternary amines are preferable in that the inorganic particles hydrophobized with amines are unlikely to react.

Specific examples of the amine include the general formula R ¹ R ² R ³ N (2)
(Wherein R ¹ , R ² and R ³ are each independently a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, a phenyl group or a phenoxy group, which may be linked to each other to form a ring. .)
The compound represented by these is mentioned.

  In the general formula (2), the alkyl group is not particularly limited, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, and an isopropyl group. Although it does not specifically limit as an aryl group, A phenyl group etc. are mentioned. Although it does not specifically limit as an alkoxy group, A methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned.

  Specific examples of the amine include triethylamine, isophoronediamine, 1,8-diazabicyclo [5,4,0] undecene-7 (DBU), bis (2-monophorinoethyl) ether, and the like. Good. Of these, bis (2-monomorpholinoethyl) ether is preferred.

  The content of inorganic particles in the toner is usually 0.1 to 20% by mass, and preferably 1 to 10% by mass. If the content of the inorganic particles is less than 0.1% by mass, the toner may easily aggregate, and if it exceeds 20% by mass, the low-temperature fixability may be deteriorated.

  The binder resin is not particularly limited, and may be a resin produced by a pulverization method or a resin produced by a polymerization method, but a urea-modified polyester is preferable. The urea-modified polyester can be synthesized by reacting a polyester prepolymer having an isocyanate group with a compound having an amino group.

  The urea-modified polyester may have a urethane bond. At this time, the ratio of the equivalent of the urethane bond to the total equivalent of the urea bond and the urethane bond is usually 0 to 90%, preferably 20 to 80%, and more preferably 40 to 70%. If the ratio of the equivalents of urethane bonds to the total equivalents of urea bonds and urethane bonds exceeds 90%, the offset resistance of the toner may decrease.

  The polyester prepolymer having an isocyanate group can be synthesized by reacting a polycondensate of a polyol and a polycarboxylic acid with a polyisocyanate.

  The polyol is not particularly limited, but alkylene glycol such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, Alkylene ether glycols such as dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, alicyclic diols such as 1,4-cyclohexanedimethanol, hydrogenated bisphenol A, ethylene oxide and propylene oxide , Alkylene oxide adducts of alicyclic diols to which alkylene oxides such as butylene oxide are added, bisphenol A, bisphenol F, bisphenol Diols such as bisphenols such as diol S, alkylene oxide adducts of bisphenols in which alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide are added to bisphenols; glycerin, trimethylolethane, trimethylolpropane, pentaerythritol , Trihydric or higher polyhydric aliphatic alcohols such as sorbitol, trihydric or higher polyphenols such as trisphenol PA, phenol novolak, cresol novolac, and trihydric or higher polyphenols such as ethylene oxide, propylene oxide, butylene oxide, etc. Examples include trivalent or higher polyols such as alkylene oxide adducts of trivalent or higher polyphenols to which oxide is added. It may be. Among them, a diol or a mixture of a diol and a trihydric or higher polyol is preferable, an alkylene glycol having 2 to 12 carbon atoms, an alkylene oxide adduct of bisphenols is more preferable, an alkylene oxide adduct of bisphenols, an alkylene oxide of bisphenols A mixture of an adduct and an alkylene glycol having 2 to 12 carbon atoms is particularly preferable.

  The mass ratio of the trihydric or higher polyol to the diol in the mixture of the diol and the trihydric or higher polyol is usually 0.01 to 10%, preferably 0.01 to 1%.

  The polycarboxylic acid is not particularly limited, but includes alkylene dicarboxylic acids such as succinic acid, adipic acid and sebacic acid, alkenylene dicarboxylic acids such as maleic acid and fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid and the like. Examples include dicarboxylic acids such as aromatic dicarboxylic acids; trivalent or higher polycarboxylic acids such as aromatic polycarboxylic acids such as trimellitic acid and pyromellitic acid, and two or more of them may be used in combination. Among them, dicarboxylic acid or a mixture of dicarboxylic acid and trivalent or higher polycarboxylic acid is preferable, alkenylene dicarboxylic acid having 4 to 20 carbon atoms, and aromatic dicarboxylic acid having 8 to 20 carbon atoms are more preferable.

  In the mixture of the dicarboxylic acid and the trivalent or higher polycarboxylic acid, the trivalent or higher polycarboxylic acid and the mass ratio with respect to the dicarboxylic acid are usually 0.01 to 10%, preferably 0.01 to 1%.

  The polycarboxylic acid may be an acid anhydride or a lower alkyl ester such as methyl ester, ethyl ester or isopropyl ester.

  The equivalent ratio of the hydroxyl group of the polyol to the carboxyl group of the polycarboxylic acid in the polycondensation of the polyol and the polycarboxylic acid is usually 1 to 2, preferably 1 to 1.5, and preferably 1.02 to 1.3. Further preferred. When this equivalent ratio exceeds 2, polycondensation does not proceed sufficiently, and when it is less than 1, the yield of the polyester prepolymer having an isocyanate group decreases.

  Polyisocyanate is not particularly limited, but tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethyl caproate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, Aliphatic polyisocyanates such as tetramethylhexane diisocyanate; cycloaliphatic polyisocyanates such as isophorone diisocyanate and cyclohexylmethane diisocyanate; tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, diphenylene-4,4′-diisocyanate, 4 , 4'-Diisocyanato-3,3'-dimethyldipheny , Aromatic diisocyanates such as 3-methyldiphenylmethane-4,4′-diisocyanate, diphenyl ether-4,4′-diisocyanate; araliphatic diisocyanates such as α, α, α ′, α′-tetramethylxylylene diisocyanate; Isocyanurates such as (isocyanatoalkyl) isocyanurate and tris (isocyanatocycloalkyl) isocyanurate are listed, and two or more may be used in combination. Among these, a diisocyanate derivative of a polycondensation product of a polyol and a polycarboxylic acid is preferable.

  The polyisocyanate may have its isocyanate group blocked with a phenol derivative, oxime, caprolactam or the like.

  The equivalent ratio of the isocyanate group of the polyisocyanate to the hydroxyl group of the polycondensation product when the polyisocyanate of the polyol and polycarboxylic acid is reacted is usually 1 to 5, preferably 1.2 to 1. 5 to 2.5 is more preferable. When the equivalent ratio is less than 1 or exceeds 5, the toner fixability may be lowered.

  The content of the polyisocyanate in the polyester prepolymer having an isocyanate group is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. When the content is less than 0.5% by mass, the offset resistance of the toner is lowered, and it may be difficult to achieve both the heat resistant storage stability and the low-temperature fixability of the toner, and exceeds 40% by mass. In this case, the low-temperature fixability may be lowered.

  The content of the polyol in the polyester prepolymer having an isocyanate group is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. When the content is less than 0.5% by mass, the offset resistance of the toner is lowered, and it may be difficult to achieve both the heat resistant storage stability and the low-temperature fixability of the toner. If it exceeds, the low-temperature fixability may deteriorate.

  The content of isocyanate groups per molecule of the polyester prepolymer having an isocyanate group is usually 1 or more, preferably 1.5 to 3, more preferably 1.8 to 2.5. When the content is less than 1, the molecular weight of the urea-modified polyester is decreased, and the offset resistance of the toner may be lowered.

  In addition, instead of the isocyanate group of the polyester prepolymer having an isocyanate group, a polyol resin having a functional group capable of reacting with an active hydrogen group such as an isocyanate group, an epoxy group, a carboxyl group, or a chlorocarbonyl group, an acrylic resin, Resins such as polyester and epoxy resin can be used.

  Although it does not specifically limit as a compound which has an amino group, Aromatic diamine, such as phenylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylmethane, diamino Cyclohexane, isophorone diamine and other alicyclic diamines, ethylene diamine, tetramethylene diamine, hexamethylene diamine, and other aliphatic diamines, etc .; diethylene triamine, triethylene tetramine, and other polyamines; ethanolamine, hydroxyethyl aniline, etc. Examples include amino alcohols; amino mercaptans such as aminoethyl mercaptan and aminopropyl mercaptan; amino acids such as aminopropionic acid and aminocaproic acid, and the like. Of these, diamine, a mixture of diamine and trivalent or higher polyamine is preferable.

  The compound having an amino group may be ketimine whose amino group is blocked with a ketone such as acetone, methyl ethyl ketone, or methyl isobutyl ketone, or oxazolidine whose amino group is blocked with an aldehyde.

  When the polyester prepolymer having an isocyanate group and the compound having an amino group are reacted, the equivalent ratio of the isocyanate group of the polyester prepolymer having an isocyanate group to the amino group of the compound having an amino group is usually 0.5 to 2. Yes, 2/3 to 1.5 are preferable, and 5/6 to 1.2 are more preferable. When this equivalence ratio is less than 0.5 or exceeds 2, the molecular weight of the urea-modified polyester becomes small, and the offset resistance of the toner may be lowered.

  In order to stop the reaction between the polyester prepolymer having an isocyanate group and the compound having an amino group, a reaction terminator can be used. Thereby, the molecular weight of the urea-modified polyester can be controlled within a desired range.

  The reaction terminator is not particularly limited, and examples thereof include monoamines such as diethylamine, dibutylamine, butylamine, and laurylamine.

  The monoamine may be ketimine whose amino group is blocked with a ketone such as acetone, methyl ethyl ketone, or methyl isobutyl ketone, or oxazolidine whose amino group is blocked with an aldehyde.

  Instead of the compound having an amino group, a compound having an active hydrogen group such as a hydroxyl group (alcoholic hydroxyl group or phenolic hydroxyl group), an amino group, a carboxyl group, or a mercapto group can be used.

  At this time, urea-modified polyester and polyester may be used in combination in order to improve low-temperature fixability and glossiness. Although it does not specifically limit as polyester, The polycondensate of a polyol and polycarboxylic acid etc. are mentioned.

  The polyester preferably has a similar structure in which a part thereof can be compatible with the urea-modified polyester, that is, it can be compatible with the urea-modified polyester, in terms of low-temperature fixability and offset resistance.

The weight average molecular weight of the polyester is usually 1 × 10 ^{3 to} 3 × 10 ⁴ , preferably 1.5 × 10 ³ to 1 × 10 ^{4, and} more preferably 2 × 10 ³ to 8 × 10 ³ . If the weight average molecular weight of the polyester is less than 1 × 10 ³ , the heat-resistant storage stability of the toner may be lowered, and if it exceeds 1 × 10 ⁴ , the low-temperature fixability of the toner may be lowered.

  The hydroxyl value of the polyester is usually 5 mgKOH / g or more, preferably 10 to 120 mgKOH / g, more preferably 20 to 80 mgKOH / g. If the hydroxyl value of the polyester is less than 5 mgKOH / g, it may be difficult to achieve both heat-resistant storage stability and low-temperature fixability of the toner.

  The acid value of the polyester is usually 1 to 30 mgKOH / g, preferably 5 to 20 mgKOH / g. As a result, the toner tends to be negatively charged.

Specific examples of the binder resin include the following combinations (1) to (10).
(1) A urea-modified polyester produced by reacting a polyester prepolymer produced by reacting an isophorone diisocyanate with a polycondensate of ethylene oxide 2 mol adduct of bisphenol A and isophthalic acid, and bisphenol (2) Polyester prepolymer produced by reacting bisphenol A ethylene oxide 2-mole adduct and isophthalic acid polycondensate with isophorone diisocyanate. Mixture of urea-modified polyester produced by reacting polymer with isophoronediamine, bisphenol A ethylene oxide 2-mol adduct and terephthalic acid polycondensate (3) bisphenol Produced by reacting isophorone diamine with a polyester prepolymer produced by reacting a polycondensate of ethylene oxide 2 mol adduct of olephenol A, propylene oxide 2 mol adduct of bisphenol A and polycondensate of terephthalic acid. (4) Bisphenol A ethylene oxide 2-mole adduct, Bisphenol A ethylene oxide 2-mole adduct, Bisphenol A propylene oxide 2-mole adduct and terephthalic acid polycondensate (4) A polyester prepolymer formed by reacting a 2-condensate of propylene oxide of A and a polycondensate of terephthalic acid with isophorone diisocyanate can react with isophorone diamine. (5) Bisphenol A ethylene oxide 2-mole adduct and terephthalic acid polycondensate and isophorone diisocyanate (6) A mixture of a polyester prepolymer produced by reacting urea and a urea-modified polyester produced by reacting hexamethylenediamine with a 2-mol adduct of bisphenol A and a polycondensate of terephthalic acid By reacting hexamethylenediamine with a polyester prepolymer formed by reacting a bicondensate of bisphenol A with ethylene oxide and a polycondensate of terephthalic acid with isophorone diisocyanate. (7) Bisphenol A ethylene oxide 2-mole adduct: Bisphenol A ethylene oxide 2-mole adduct, bisphenol A propylene oxide 2-mole adduct and terephthalic acid polycondensate And a polyester prepolymer produced by reacting a polycondensate of terephthalic acid with isophorone diisocyanate, and a urea-modified polyester produced by reacting ethylenediamine with an ethylene oxide 2-mole adduct of bisphenol A and a polymer of terephthalic acid. Mixture with condensate (8) Polyester prepolymer produced by reacting diphenylmethane diisocyanate with polycondensate of ethylene oxide 2 mol adduct of bisphenol A and isophthalic acid (9) Bisphenol A ethylene oxide 2-mole adduct, bisphenol A mixture of urea-modified polyester formed by reacting hexamethylenediamine with bisphenol A ethylene oxide 2-mole adduct and isophthalic acid polycondensate A urea-modified polyester formed by reacting hexamethylenediamine with a polyester prepolymer formed by reacting a polycondensate of propylene oxide 2 mol adduct of A, a polycondensate of terephthalic acid and dodecenyl succinic anhydride with diphenylmethane diisocyanate; , A mixture of bisphenol A ethylene oxide 2 mol adduct, bisphenol A propylene oxide 2 mol adduct and polycondensate of terephthalic acid (10) Ethylene of bisphenol A Polyester prepolymer produced by reacting 2-condensate of oxide and polycondensate of isophthalic acid with toluene diisocyanate, urea-modified polyester produced by reacting hexamethylenediamine, and 2 mol of ethylene oxide of bisphenol A Mixture with adduct and polycondensate of isophthalic acid The binder resin usually has a weight average molecular weight of 1 × 10 ⁴ or more, preferably 2 × 10 ⁴ to 1 × 10 ⁷ , and 3 × 10 ⁴ to 1 ×. 10 ⁶ is more preferable. When the weight average molecular weight of the binder resin is less than 1 × 10 ⁴ , the hot offset resistance of the toner may be lowered.

The number average molecular weight of the binder resin is usually 2 × 10 ⁴ or less, preferably 1 × 10 ³ to 1 × 10 ^4, more preferably 2 × 10 ³ to 8 × 10 ³ . When the number average molecular weight of the binder resin exceeds 2 × 10 ⁴ , the low-temperature fixability and glossiness of the toner may be deteriorated.

  The molecular weight of the binder resin can be measured using GPC.

  The glass transition point of the binder resin is usually 40 to 70 ° C, preferably 55 to 65 ° C. When the glass transition point of the binder resin is less than 40 ° C., the heat-resistant storage stability of the toner may be lowered, and when it exceeds 70 ° C., the low-temperature fixability may be lowered.

  The glass transition point of the binder resin can be measured using a TG-DSC system TAS-100 (manufactured by Rigaku Corporation).

The storage elastic modulus temperature of the binder resin, that is, the temperature at which the storage elastic modulus of the binder resin becomes 10,000 dyne / cm ^{2 at} a measurement frequency of 20 Hz is usually 100 ° C. or higher, and preferably 110 to 200 ° C. When the storage elastic modulus temperature of the binder resin is less than 100 ° C., the offset resistance of the toner may be lowered.

  The viscosity temperature of the binder resin, that is, the temperature at which the viscosity of the binder resin becomes 1000 poise at a measurement frequency of 20 Hz is usually 180 ° C. or less, preferably 90 to 160 ° C. When the viscosity temperature of the binder resin exceeds 180 ° C., the low-temperature fixability of the toner may be deteriorated.

  Further, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability, the storage elastic modulus temperature of the binder resin is preferably equal to or higher than the viscosity temperature of the binder resin. At this time, the difference between the storage elastic modulus temperature of the binder resin and the viscosity temperature of the binder resin is usually 0 to 100 ° C, preferably 10 to 90 ° C, and more preferably 20 to 80 ° C.

  The colorant is not particularly limited as long as it is a dye or a pigment, but carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow Lead, Titanium Yellow, Polyazo Yellow, Oil Yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R) , Tartrazine rake, quinoline yellow rake, anthrazan yellow BGL, isoindolinone yellow, bengara, red lead, lead vermilion, cadmium red, cadmium mercurial red, antimon vermilion, permanent red 4R, para red, phise red, parachloro ortho Nitroani Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Poly Zored, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyani N, Green, Anthraquinone Green, Titanium Oxide, Zinc Hana, Litobon, etc., may be used in combination.

  The content of the colorant in the toner is usually 1 to 15% by mass, and preferably 3 to 10% by mass. When the content of the colorant in the toner is less than 1% by mass, the coloring power may be insufficient, and when it exceeds 15% by mass, the fixing of the toner may be inhibited.

  The colorant may be used as a master batch that is combined with the resin.

  The resin is not particularly limited, but a polymer of styrene or its substitute, a styrene copolymer, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin , Epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin, alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. And two or more of them may be used in combination.

  Examples of the styrene or substituted polymer thereof include polystyrene, poly (p-chlorostyrene), and polyvinyl toluene.

  As the styrene copolymer, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, Styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate Copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Indene copolymer, styrene-mer Ynoic acid copolymer, styrene - maleic acid ester copolymers and the like.

  Although it does not specifically limit as a method of manufacturing a masterbatch, The method of mixing or knead | mixing resin and a coloring agent is mentioned. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. In addition, it is preferable to use a flushing method as a method for producing a masterbatch because a wet cake of a colorant can be used as it is and does not need to be dried. The flushing method is a method in which an aqueous paste of a colorant, a resin, and an organic solvent are mixed or kneaded, and after the colorant is transferred to the resin side, moisture and the organic solvent are removed.

  The apparatus used for mixing or kneading is not particularly limited, and examples thereof include a high shear dispersion apparatus such as a three roll mill.

  Content of the coloring agent in a masterbatch is 80 mass% or less normally, and 30-60 mass% is preferable.

  The toner of the present invention may further contain a charge control agent.

  The charge control agent is not particularly limited, but triphenylmethane dye, molybdate chelate pigment, rhodamine dye, alkoxy amine, quaternary ammonium salt including fluorine-modified quaternary ammonium salt, alkylamide, phosphorus alone or Compound, simple substance or compound of tungsten, fluorine-based surfactant, salicylic acid metal salt, salicylic acid derivative metal salt, quinacridone, azo pigment, sulfonic acid group, carboxyl group, quaternary ammonium salt, etc. A compound etc. are mentioned and you may use 2 or more types together. At this time, if a colored material is used as the charge control agent, the color tone may change. Therefore, it is preferable to use a colorless or white material.

  Commercially available charge control agents include quaternary ammonium salt Bontron P-51, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E-84, phenolic condensate E-89 (above, Orient Chemical Co., Ltd.) quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR Quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, boron complex LR-147 (manufactured by Nippon Carlit), and the like.

  The charge control agent may be mixed or kneaded with the colorant when the master batch is produced, or may be fixed to the surface of the base particles.

  The content of the charge control agent in the toner is usually from 0.1 to 10% by weight, preferably from 0.2 to 5% by weight, based on the binder resin. When the content of the charge control agent in the toner is less than 0.1% by mass with respect to the binder resin, the toner may have insufficient chargeability. When the content exceeds 10% by mass, the developing roller Electrostatic attraction force may increase, and the fluidity of the toner may decrease or the image density may decrease.

  In the toner of the present invention, a cleaning property improving agent may be fixed to the surface of the base particle.

  The cleaning property improver is not particularly limited, and examples thereof include fatty acid metal salts such as zinc stearate and calcium stearate; resin particles produced by soap-free emulsion polymerization such as polymethyl methacrylate particles and polystyrene particles.

  The resin particles usually have a volume average particle size of 0.01 to 1 μm.

  The content of the resin component not dissolved in tetrahydrofuran in the toner of the present invention is usually 1 to 15% by mass. When the content of the resin component that does not dissolve in tetrahydrofuran in the toner of the present invention is less than 1% by mass, the hot-off resistance may be deteriorated, and when it exceeds 15% by mass, the glossiness and transparency are deteriorated. Sometimes.

  The content of the resin component not dissolved in tetrahydrofuran in the toner can be measured as follows. First, the content A [mass%] of a component not dissolved in tetrahydrofuran other than the resin component in the toner is measured by measuring the heat loss of the toner by the TG method. Next, about 50 g of tetrahydrofuran is added to about 1.0 g of the toner and left to stand at 20 ° C. for 24 hours, followed by centrifugation. Furthermore, after filtering using 5 types C quantitative filter paper prescribed | regulated by JISP3801, the filtrate is vacuum-dried and content B [mass%] of the resin component melt | dissolved in tetrahydrofuran is measured. At this time, the content of the resin component not dissolved in tetrahydrofuran in the toner is 100-A-B [mass%].

  The glass transition point of the toner of the present invention is usually from 40 to 70 ° C, preferably from 55 to 65 ° C. When the glass transition point of the toner of the present invention is less than 40 ° C., the heat-resistant storage stability may be lowered, and when it exceeds 70 ° C., the low-temperature fixability may be lowered.

  The glass transition point of the toner can be measured using a TG-DSC system TAS-100 (manufactured by Rigaku Corporation).

  The softening temperature of the toner of the present invention is usually 50 ° C. or higher, and preferably 80 to 120 ° C. When the softening temperature of the toner of the present invention is less than 50 ° C., heat-resistant storage stability and / or low-temperature storage stability may be deteriorated.

  The outflow start temperature of the toner of the present invention is usually 80 to 170 ° C., preferably 100 to 150 ° C. When the outflow start temperature of the toner of the present invention is less than 80 ° C., heat-resistant storage stability and / or low-temperature storage stability may be deteriorated, and when it exceeds 170 ° C., low-temperature fixability may be deteriorated.

  The half-method softening point of the toner of the present invention is usually 60 ° C. or higher, and preferably 80 to 170 ° C. When the 1/2 method softening point of the toner of the present invention is less than 60 ° C., the heat-resistant storage property and / or the low-temperature storage property may deteriorate.

  The softening temperature, outflow start temperature, and 1/2 method softening point of the toner can be measured using an elevated flow tester CFT500 type (manufactured by Shimadzu Corporation).

  The average circularity of the toner of the present invention is preferably 0.94 to 0.98. When the average circularity of the toner of the present invention is less than 0.94, the transferability may be lowered, and a high-quality image free from dust may not be formed.

  The average circularity of the toner can be measured using a flow type particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation).

  The volume average particle size of the toner of the present invention is preferably 3 to 8 μm. When the volume average particle size of the toner of the present invention is less than 3 μm, the toner may be easily fused, and when it exceeds 8 μm, it may be difficult to form a high-quality image.

  In the toner of the present invention, the content of components having a particle size of 25 μm or more is preferably 0.5% by mass or less. When the content of a component having a particle diameter of 25 μm or more of the toner of the present invention exceeds 0.5% by mass, it may be difficult to form a high-quality image.

  The ratio of the volume average particle diameter to the number average particle diameter of the toner of the present invention is usually 1.00 to 1.25, preferably 1.05 to 1.20. When the ratio of the volume average particle diameter to the number average particle diameter of the toner of the present invention exceeds 1.25, it may be difficult to form a high quality image.

  The particle size distribution of the toner can be measured using a particle size measuring device Coulter Counter TAII (manufactured by Coulter Electronics).

  The method for producing a toner of the present invention comprises dissolving or dispersing a toner material containing a polyester prepolymer having an isocyanate group, a compound having an amino group, a colorant, paraffin wax, microcrystalline wax and inorganic particles in an organic solvent. A step of preparing one liquid, a step of preparing a second liquid by emulsifying or dispersing the first liquid in an aqueous medium containing resin particles, and a step of removing an organic solvent from the second liquid. . At this time, the ratio of the mass of the paraffin wax to the total mass of the paraffin wax and the microcrystalline wax is 5 to 15%.

  The toner material may further contain polyester.

  The ratio of the mass of the polyester prepolymer having an isocyanate group to the total mass of the polyester prepolymer having a polyester and an isocyanate group is preferably 5 to 25%, more preferably 8 to 25%, and particularly preferably 8 to 22%. preferable. When this ratio is less than 5%, the offset resistance of the toner is lowered, and it may be difficult to achieve both the heat-resistant storage stability and the low-temperature fixability of the toner. Fixability may be reduced.

  The toner material may be added before emulsifying or dispersing the first liquid in the aqueous medium, except for the component containing a resin such as a polyester prepolymer having an isocyanate group, or in the aqueous medium. It may be added when emulsifying or dispersing the first liquid, or may be added after emulsifying or dispersing the first liquid in the aqueous medium. At this time, the inorganic particles may be added as they are, or may be added as a dispersion of inorganic particles.

  The volume average particle size of the paraffin wax and microcrystalline wax in the first liquid is usually 0.1 to 2 μm, preferably 0.1 to 1 μm. If the volume average particle diameter of the paraffin wax and microcrystalline wax is less than 0.1 μm, the releasability of the toner during low-temperature fixing may deteriorate. If it exceeds 2 μm, the paraffin wax and microcrystalline wax are contained in the toner. May be dispersed unevenly.

  The organic solvent is not particularly limited as long as it can dissolve or disperse the toner material, but toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane. , Trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, and the like. Among these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable because they can be easily removed.

  The amount of the organic solvent used is usually 40 to 300 parts by weight, preferably 60 to 140 parts by weight, and more preferably 80 to 120 parts by weight with respect to 100 parts by weight of the toner material.

  The disperser used when emulsifying or dispersing the first liquid in the aqueous medium is not particularly limited, but a low speed shear disperser, a high speed shear disperser, a friction disperser, a high pressure jet disperser, an ultra Examples thereof include a sonic disperser. Among these, a high-speed shearing disperser is preferable in that the particle size of the first liquid dispersion can be controlled to 2 to 20 μm.

When using a high-speed shearing disperser, the number of rotations is usually 1 × 10 ^{3 to} 3 × 10 ⁴ rpm, preferably 5 × 10 ³ to 2 × 10 ⁴ rpm. The dispersion time is usually 0.1 to 5 minutes in the case of a batch method. Further, the dispersion temperature is usually 0 to 150 ° C., preferably 40 to 98 ° C. under pressure.

  The amount of the aqueous medium used is usually 50 to 2000 parts by mass, preferably 100 to 1000 parts by mass with respect to 100 parts by mass of the toner material. When the amount of the aqueous medium used is less than 50 parts by mass with respect to 100 parts by mass of the toner material, base particles having a predetermined particle diameter may not be obtained. May be.

  In the aqueous medium, resin particles are dispersed in water. At this time, a solvent miscible with water can be used in combination with water. Solvents miscible with water include alcohols such as methanol, isopropanol and ethylene glycol, cellosolves such as dimethylformamide, tetrahydrofuran and methyl cellosolve, and lower ketones such as acetone and methyl ethyl ketone. Also good. Among these, the organic solvent contained in the first liquid is preferable. At this time, the water is preferably saturated with the first liquid.

  The content of the resin particles in the aqueous medium is usually 0.5 to 10% by mass.

  The resin particles may be contained in the base particles, but are preferably fixed to the surface of the base particles. In this case, the resin particles can control the toner offset resistance, heat resistant storage stability, and low temperature fixability.

The weight average molecular weight of the resin particles is usually 9 × 10 ³ to 2 × 10 ⁵ , and preferably 1 × 10 ^{4 to} 5 × 10 ⁴ . When the weight average molecular weight of the resin particles is less than 9 × 10 ³ , the heat resistant storage stability of the toner may be lowered, and when it exceeds 2 × 10 ⁵ , the low temperature fixability may be lowered.

  The weight average molecular weight of the resin particles can be measured using GPC.

  The volume average particle diameter of the resin particles is usually 20 to 400 nm, preferably 30 to 200 nm, and more preferably 40 to 120 nm. When the volume average particle diameter of the resin particles is less than 20 nm, the resin particles may inhibit the adhesion between the binder resin and the recording medium, and the low-temperature fixability may be deteriorated. Resin particles may be detached from the toner due to agitation stress.

  The volume average particle size of the resin particles can be measured using a particle size distribution measuring device nanotrac UPA-150EX (manufactured by Nikkiso Co., Ltd.).

  The glass transition point of the resin particles is usually 40 to 150 ° C, preferably 45 to 80 ° C. If the glass transition point of the resin particles is less than 40 ° C., the heat-resistant storage stability of the toner may be lowered, and if it exceeds 150 ° C., the low-temperature fixability may be lowered.

  The glass transition point of the resin particles can be measured using a differential scanning calorimeter DSC-60 (manufactured by Shimadzu Corporation).

  The content of the resin particles in the toner is usually 0.2 to 6.0% by mass. When the content of the resin particles in the toner is less than 0.2% by mass, the heat-resistant storage stability of the toner may be lowered. Particles may be detached.

  The content of the resin particles in the toner can be calculated from the area of the peak due to only the resin particles using a pyrolysis gas chromatograph mass spectrometer.

  The resin constituting the resin particle is not particularly limited as long as it can be dispersed in water, but vinyl resin, urethane resin, epoxy resin, polyester, polyamide, polyimide, silicon resin, phenol resin, melamine resin, urea Resins, aniline resins, ionomer resins, polycarbonates and the like may be mentioned, and two or more of them may be used in combination. Among these, vinyl resin, urethane resin, epoxy resin, and polyester resin are preferable, and vinyl resin is more preferable because an aqueous dispersion of fine spherical resin particles is easily obtained.

  Vinyl resins include styrene- (meth) acrylic acid ester copolymer, styrene-butadiene copolymer, (meth) acrylic acid-acrylic acid ester copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer. Examples thereof include a polymer and a styrene- (meth) acrylic acid copolymer.

  The resin particles are usually obtained as a dispersion of resin particles, but the dispersion of resin particles may be used as it is in the production of toner, or only the resin particles contained in the dispersion of resin particles are produced in the toner. You may use for. When only the resin particles contained in the resin particle dispersion are used for toner production, the resin particles are obtained by washing the resin particle dispersion with, for example, water and then vacuum drying.

  The resin particles are preferably synthesized using a monomer having a plurality of unsaturated groups.

  The addition amount of the monomer having a plurality of unsaturated groups is usually 0.3 to 20% by mass, preferably 0.5 to 5% by mass, based on the total amount of the monomer. When the addition amount of the monomer having a plurality of unsaturated groups is less than 0.3% by mass relative to the total amount of the monomer, the crosslinking density of the resin particles may be insufficient, and 20% by mass. Exceeding may cause the adhesion of the resin particles to the toner surface to decrease.

  Although it does not specifically limit as a monomer which has two or more unsaturated groups, Sodium salt Eleminol RS-30 (made by Sanyo Kasei Kogyo Co., Ltd.) of the sulfate ester of the ethylene oxide addition product of methacrylic acid etc. are mentioned.

  The method for synthesizing the resin particles is not particularly limited, and examples include a soap-free emulsion polymerization method, a suspension polymerization method, and a dispersion polymerization method.

  The aqueous medium preferably further contains a dispersant from the viewpoint of narrowing the particle size distribution of the toner.

  Although it does not specifically limit as a dispersing agent, Surfactant, a slightly water-soluble inorganic compound, a polymeric protective colloid, etc. are mentioned, You may use 2 or more types together. Of these, surfactants are preferred.

  Examples of the surfactant include an anionic surfactant, a cationic surfactant, a nonionic surfactant, and an amphoteric surfactant.

  Examples of the anionic surfactant include alkylbenzene sulfonate, α-olefin sulfonate, phosphate ester, and the like, and an anionic surfactant having a fluoroalkyl group is preferable.

  Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkyl carboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-11) oxy. ] -1-alkyl (C3-4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-20) carboxylic acid or Its metal salt, perfluoroalkyl carboxylic acid (C7-13) or its metal salt, perfluoroalkyl (C4-12) sulfonic acid or its metal salt, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- (2 -Hydroxyethyl) perfluorooctanesulfonami And perfluoroalkyl (C6-10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-16) ethyl phosphate, and the like.

  Commercially available anionic surfactants having a fluoroalkyl group include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.); Fluorard FC-93, FC-95, FC-98, FC-129 (Manufactured by Sumitomo 3M); Unidyne DS-101, DS-102 (manufactured by Daikin Industries); Megafac F-110, F-120, F-113, F-191, F-812, F-833 (DIC Corporation) Xttop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products); Footent F-100, F-150 (manufactured by Neos) Etc.

  As cationic surfactants, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt type surfactants such as imidazoline; alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridiniums Quaternary ammonium salt type surfactants such as salts, alkylisoquinolinium salts, benzethonium chloride and the like can be mentioned, and cationic surfactants having a fluoroalkyl group are preferred.

  Examples of the cationic surfactant having a fluoroalkyl group include aliphatic primary, secondary, or tertiary amine acids having a fluoroalkyl group, and aliphatic 4 such as perfluoroalkyl (C6-10) sulfonamidopropyltrimethylammonium salt. Examples include quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like.

  Commercially available cationic surfactants having a fluoroalkyl group include Surflon S-121 (manufactured by Asahi Glass Co., Ltd.); Florard FC-135 (manufactured by Sumitomo 3M Co.); Unidyne DS-202 (manufactured by Daikin Industries), MegaFuck F-150, F-824 (manufactured by DIC); X-top EF-132 (manufactured by Tochem Products); and footent F-300 (manufactured by Neos).

  Examples of nonionic surfactants include fatty acid amide derivatives and polyhydric alcohol derivatives.

  Examples of the amphoteric surfactant include alanine, dodecyl bis (aminoethyl) glycine, bis (octylaminoethyl) glycine, N-alkyl-N, N-dimethylammonium betaine and the like.

  Examples of the poorly water-soluble inorganic compound include tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite.

  If the aqueous medium contains a compound that can be dissolved in an acid or alkali such as tricalcium phosphate, the tricalcium phosphate is dissolved with an acid such as hydrochloric acid and then washed with water, or decomposed with an enzyme. The tricalcium phosphate can be removed from the base particles by a method or the like.

  Polymeric protective colloids include monomers having a carboxyl group such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, etc. ; Β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2 acrylate -Hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, etc. (Meth) acrylic monomers; vinyl alkyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether; vinyl carboxylates such as vinyl acetate, vinyl propionate, vinyl butyrate; acrylamide, methacrylamide, diacetone acrylamide, etc. (Meth) acrylic monomers having an amide group; methylolated products of (meth) acrylic monomers having an amide group such as N-methylolacrylamide, N-methylolmethacrylamide; acrylic acid chloride, methacrylic acid chloride, etc. A chloride of a (meth) acrylic monomer having a carboxyl group: a homopolymer or copolymer such as a monomer having a nitrogen atom such as vinylpyridine, vinylpyrrolidone, vinylimidazole or ethyleneimine or a heterocyclic ring thereof; Cited . Polymer protective colloids other than these include polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, Examples include polyoxyethylene resins such as polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, and polyoxyethylene nonyl phenyl ester; and celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

  The aqueous medium may further contain a catalyst for promoting the reaction between the polyester prepolymer having an isocyanate group and the compound having an amino group.

  Although it does not specifically limit as a catalyst, Dibutyltin laurate, dioctyltin laurate, etc. are mentioned.

  The reaction time for reacting the polyester prepolymer having an isocyanate group and the compound having an amino group contained in the second liquid is usually 10 minutes to 40 hours, and preferably 2 to 24 hours. Moreover, reaction temperature is 0-150 degreeC normally, and 40-98 degreeC is preferable.

  As a method for removing the organic solvent from the second liquid, a method of gradually elevating the temperature of the second liquid to evaporate the organic solvent, spraying the second liquid into a dry atmosphere, and removing the organic solvent and water. The method of evaporating etc. is mentioned.

  Although it does not specifically limit as dry atmosphere, Heating atmosphere, such as air, nitrogen, a carbon dioxide gas, combustion gas, is mentioned. At this time, the temperature of the heating atmosphere is preferably equal to or higher than the boiling points of the organic solvent and water.

  The device for spraying the second liquid in a dry atmosphere to evaporate the organic solvent and water is not particularly limited, and examples thereof include a spray dryer, a belt dryer, and a rotary kiln.

  When the organic solvent is removed from the second liquid, a dispersion liquid or base particles in which the base particles are dispersed in an aqueous medium is obtained.

  The dispersion liquid or the base particles in which the base particles are dispersed in the aqueous medium is preferably washed with water and then vacuum-dried. Thereby, a dispersing agent can be removed.

  At this time, the base particles may be classified as necessary.

  The method of classifying the base particles is not particularly limited, and examples thereof include a method of removing fine particles by a cyclone, a decanter, and centrifugation, a method of removing coarse particles by a mesh, and the like.

  The method for producing the toner of the present invention is not limited to the above method, and may be a polymerization method such as a suspension polymerization method or an emulsion polymerization method; a pulverization method. At this time, the inorganic particles may be added before the base particles are formed. Moreover, when using the polymerization method, resin particles may be added before the base particles are formed.

  When adding resin particles to the base particles, Henschel mixer (Mitsui Miike Co., Ltd.), super mixer (Kawada Seisakusho Co., Ltd.), Q mixer (Mitsui Mining Co., Ltd.), mechano-fusion system (Hosokawa Micron Co., Ltd.), mechano mill ( A mixing / stirring apparatus such as Okada Seiko Co., Ltd. can be used.

  The developer of the present invention may be a one-component developer including the toner of the present invention, and may be a two-component developer including a toner and a carrier.

  The content of the carrier in the two-component developer is usually 90 to 98% by mass, preferably 93 to 97% by mass.

  The carrier preferably has a core material coated with a resin layer.

  Although it does not specifically limit as a material which comprises a core material, 50-90 emu / g manganese-strontium type material, manganese-magnesium type material, etc. are mentioned, You may use 2 or more types together. Among these, from the viewpoint of securing the image density, highly magnetized materials such as iron of 100 emu / g or more and magnetite of 75 to 120 emu / g are preferable. Further, a weakly magnetized material such as a copper-zinc-based material of 30 to 80 emu / g is preferable in that it can weaken the hitting of the photoconductor in which the toner is in a spiked state and is advantageous for improving the image quality.

  The volume average particle diameter of the core is usually 10 to 200 μm, preferably 20 to 150 μm, and more preferably 40 to 100 μm. When the volume average particle diameter of the core material is less than 10 μm, the magnetization per particle may be small and the carrier may be scattered, and when it exceeds 200 μm, the specific surface area may be small and the toner may be scattered. is there.

  The material constituting the resin layer is not particularly limited, but amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin; polyamide; epoxy resin; acrylic resin, polymethyl methacrylate, polyacrylonitrile, polyacetic acid Vinyl resins such as vinyl, polyvinyl alcohol and polyvinyl butyral; Styrene resins such as polystyrene and styrene-acrylic copolymers; Halogenated olefin resins such as polyvinyl chloride; Polyesters such as polyethylene terephthalate and polybutylene terephthalate; Polycarbonates; Polyethylenes; Vinyl fluoride, polyvinylidene fluoride, polytrifluoroethylene, polyhexafluoropropylene, vinylidene fluoride-acrylic copolymer, vinylidene fluoride-vinylidene fluoride Copolymer, fluorocarbon resins such as terpolymers of tetrafluoroethylene, vinylidene fluoride and non-fluorinated monomer; silicone resin and the like, may be used in combination.

  The resin layer may contain conductive powder.

  Although it does not specifically limit as a material which comprises electroconductive powder, A metal, carbon black, a titanium oxide, a tin oxide, a zinc oxide etc. are mentioned.

  The average particle size of the conductive powder is usually 1 μm or less. If the average particle size of the conductive powder exceeds 1 μm, it may be difficult to control the electrical resistance of the resin layer.

  The resin layer can be formed by applying a coating solution in which a resin is dissolved in a solvent to the surface of the core, then drying and baking.

  Although it does not specifically limit as a coating method, A dipping method, a spray method, a brush coating method, etc. are mentioned.

  Although it does not specifically limit as a solvent, Toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cellosolve, butyl acetate, etc. are mentioned.

  The baking method is not particularly limited, and examples thereof include an external heating method using a fixed electric furnace, a fluid electric furnace, a rotary electric furnace, a burner furnace, etc .; an internal heating method using microwaves, and the like.

  The content of the resin layer in the carrier is usually 0.01 to 5.0% by mass. When the content of the resin layer in the carrier is less than 0.01% by mass, it may be difficult to form a uniform resin layer on the surface of the core material. When the content exceeds 5.0% by mass, the carrier They may aggregate together.

  The developer of the present invention can be applied to image formation by various electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method.

  The image forming method of the present invention includes a step of charging a photoconductor, a step of exposing the charged photoconductor to form an electrostatic latent image, and an electrostatic latent image formed on the photoconductor as a developer of the present invention. Developing the toner image to form a toner image, transferring the toner image formed on the photosensitive member to a recording medium, and fixing the toner image transferred to the recording medium.

  The shape of the photoreceptor is not particularly limited, and examples thereof include a drum shape.

  The material constituting the photoreceptor is not particularly limited, and examples thereof include inorganic compounds such as amorphous silicon and selenium; organic compounds such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferable in terms of long life.

  Examples of the method for charging the photoconductor include a method in which a voltage is applied to the surface of the photoconductor using a charging device.

  The charging device is not particularly limited, but includes a contact charging device having a conductive or semiconductive roll, brush, film, rubber blade, etc .; a non-contact charging device using corona discharge such as corotron, scorotron, etc. .

  Examples of the method for exposing the charged photosensitive member include a method of exposing the surface of the photosensitive member using an exposure device. At this time, an optical back surface method in which the back surface of the photoreceptor is exposed may be applied.

  Examples of the exposure apparatus include, but are not limited to, various exposure apparatuses such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system.

  As a method of developing the electrostatic latent image formed on the photosensitive member with the developer of the present invention, for example, using the developing device, the toner of the present invention is applied to the electrostatic latent image formed on the surface of the photosensitive member. The method of doing is mentioned.

  The developing device is not particularly limited as long as it contains the developer of the present invention and can apply the toner of the present invention to the electrostatic latent image formed on the photoreceptor in a contact or non-contact manner. Examples of the developing device include a stirrer that stirs and charges the two-component developer as the developer of the present invention and a rotatable magnet roller. At this time, the developer of the present invention charged by friction when the toner of the present invention and the carrier are stirred in the stirrer is held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. The Since the magnet roller is disposed in the vicinity of the photosensitive member, a part of the toner of the present invention constituting the magnetic brush formed on the surface of the magnetic roller is formed on the surface of the photosensitive member by electrostatic attraction. Applied to the electrostatic latent image. As a result, the electrostatic latent image formed on the surface of the photoreceptor is developed with the developer of the present invention to form a toner image.

  The developer of the present invention accommodated in the developing device may be a one-component developer.

  Examples of a method for transferring the toner image formed on the photoconductor to the recording medium include a method for transferring the toner image formed on the surface of the photoconductor to the surface of the recording medium using a transfer device.

  The transfer device is not particularly limited, and examples include an intermediate transfer method.

  Examples of a method for fixing the toner image transferred to the recording medium include a method for fixing the toner image transferred to the surface of the recording medium using a fixing device.

  The fixing device is not particularly limited, and examples thereof include a belt fixing method and a roller fixing method.

  Examples of the present invention will be described below, but the present invention is not limited to the examples. In addition, a part means a mass part.

[Synthesis of polyester]
In a reaction vessel equipped with a condenser, a stirrer, and a nitrogen inlet tube, 229 parts of a 2-mole adduct of bisphenol A, 529 parts of a propion oxide 3-mole adduct of bisphenol A, 208 parts of terephthalic acid, 46 parts of adipic acid, and 2 parts of dibutyltin oxide was added and reacted at 230 ° C. for 8 hours under normal pressure, and then reacted for 5 hours under reduced pressure of 10 to 15 mmHg. Next, 44 parts of trimellitic anhydride was added and reacted at 180 ° C. for 2 hours under normal pressure to obtain polyester 1. The obtained polyester 1 had a number average molecular weight of 2500, a weight average molecular weight of 6700, a glass transition point of 43 ° C., and an acid value of 25 mgKOH / g.

[Synthesis of polyester prepolymer]
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 parts of acid and 2 parts of dibutyltin oxide were added, reacted at 230 ° C. under normal pressure for 7 hours, and then reacted under reduced pressure of 10 to 15 mmHg for 5 hours to obtain an intermediate polyester. The obtained intermediate polyester had a number average molecular weight of 2200, a weight average molecular weight of 9700, a peak molecular weight of 3000, a glass transition point of 54 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 52 mgKOH / g. .

  In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 410 parts of the intermediate polyester, 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate were allowed to react at 100 ° C. for 5 hours to obtain a polyester prepolymer 1. . The obtained polyester prepolymer 1 had a free isocyanate content of 1.53% by mass.

[Production of master batch]
1200 parts of water, 540 parts of carbon black Printex 35 (manufactured by Degussa) having a DBP oil absorption of 42 ml / 100 g and a pH of 9.5 and 1200 parts of polyester 1 were mixed using a Henschel mixer (manufactured by Mitsui Mining). The obtained mixture was kneaded at 150 ° C. for 30 minutes using a two-roll, and then cooled by rolling. Furthermore, it grind | pulverized using the pulperizer (made by Hosokawa Micron Corporation), and obtained the masterbatch.

[Preparation of aqueous medium]
In a reaction vessel equipped with a stirrer and a thermometer, 683 parts of water, 20 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Kasei Kogyo) of sulfuric acid ester of methacrylic acid ethylene oxide adduct, 78 parts of styrene, methacrylic acid 78 parts, 120 parts of butyl acrylate and 1 part of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes to obtain a white emulsion. The obtained emulsion was heated to 75 ° C. and reacted at 75 ° C. for 5 hours. Next, after adding 30 parts of a 1% by mass aqueous ammonium persulfate solution, the mixture was aged at 75 ° C. for 5 hours to obtain a dispersion of resin particles. The obtained dispersion of resin particles had a volume average particle size of 55 nm. Further, when a part of the dispersion of resin particles was dried to isolate the resin particles, the resin particles had a glass transition point of 48 ° C. and a weight average molecular weight of 4.5 × 10 ⁵ .

  990 parts of water, 37 parts of a 48.5% by weight aqueous solution of dodecyl diphenyl ether disulfonate, 37 parts of Eleminol MON-7 (manufactured by Sanyo Chemical Industries), 15 parts of a dispersion of resin particles and 90 parts of ethyl acetate were mixed and stirred to give a milky white aqueous system A medium was obtained.

[Molecular weight of polyester]
The molecular weight of the polyester was measured using a high-speed GPC apparatus HLC-8220 GPC (manufactured by Tosoh Corporation). Specifically, first, the polyester was dissolved in tetrahydrofuran and then filtered through a 0.2 μm filter to obtain a 0.15 mass% sample solution. Next, tetrahydrofuran was allowed to flow through the column at 0.35 ml / min in a 40 ° C. heat chamber to stabilize the column, and then 100 μl of the sample solution was injected.

  The molecular weight of the polyester was calculated from the relationship between the logarithmic value of a calibration curve prepared using a monodisperse polystyrene standard sample and the retention time. At this time, as a monodisperse polystyrene standard sample, Stowd STANDARD Std. No S-7300, S-210, S-390, S-875, S-1980, S-10.9, S-629, S-3.0, S-0.580 (made by Showa Denko KK) are used. It was. In addition, a refractive index (RI) detector was used as a detector, and a TSKgel SuperHZM-H 15 cm triple (manufactured by Tosoh Corporation) was used as a column.

[Glass transition point of polyester]
The glass transition point of polyester was measured using TG-DSC system TAS-100 (manufactured by Rigaku Corporation). Specifically, about 10 mg of polyester was packed in an aluminum sample pan, and the melting point was measured under the following temperature conditions in a nitrogen atmosphere.

Start temperature: room temperature Temperature increase rate: 10 ° C / min End temperature: 150 ° C
Holding time: 10 minutes Temperature drop: 10 ° C / min Finishing temperature: room temperature Holding time: 10 minutes Heating rate: 10 ° C / min Finishing temperature: 150 ° C
As a reference, an aluminum sample pan was used. Moreover, the measurement result was analyzed using the analysis system in TG-DSC system TAS-100 system.

[Particle size distribution of resin particle dispersion]
The particle size distribution of the dispersion of resin particles was measured using a particle size distribution measuring device nanotrac UPA-150EX (manufactured by Nikkiso Co., Ltd.).

[Glass transition point of resin particles]
The glass transition point of the resin particles was measured using a differential scanning calorimeter DSC-60 (manufactured by Shimadzu Corporation). Specifically, about 10 mg of resin particles were packed in an aluminum sample pan, and the melting point was measured under the following temperature conditions in a nitrogen atmosphere.

Start temperature: room temperature Temperature increase rate: 10 ° C / min End temperature: 200 ° C
Holding time: 10 minutes Temperature drop: 10 ° C / min Finishing temperature: Room temperature Holding time: 10 minutes Heating rate: 10 ° C / min Finishing temperature: 200 ° C
As a reference, an aluminum sample pan was used. Moreover, the measurement result was analyzed using the analysis system in TG-DSC system TAS-100 system.

[Weight average molecular weight of resin particles]
The weight average molecular weight of the resin particles was measured in the same manner as the molecular weight of the polyester.

[Example 1]
In a reaction vessel equipped with a stirrer and a thermometer, 378 parts of polyester, a melting point of 82 ° C., a paraffin wax having a weight loss of 12% at 165 ° C., a melting point of 85 ° C., and a mass loss of 165 ° C. of 1.3% A mixture of 110 parts of a microcrystalline wax having a mass ratio of 5:95 and 947 parts of ethyl acetate was added, and while stirring, the temperature was raised to 80 ° C., held at 80 ° C. for 5 hours, and then lowered to 30 ° C. over 1 hour. A wax dispersion was obtained.

  Into 1435 parts of the wax dispersion liquid, 500 parts of master batch, 12 parts of hydrophobized silica R-972 (manufactured by Aerosil) and 500 parts of ethyl acetate were charged and mixed for 1 hour to obtain a raw material mixture.

  1324 parts of the raw material mixture was transferred to a reaction vessel, filled with 80% by volume of 0.5 mm zirconia beads in a bead mill, Ultra Visco Mill (manufactured by Imex), a liquid feed speed of 1 kg / hour, and a disk peripheral speed of 6 m. 3 passes per second. Next, after adding 1324 parts of a 65 mass% ethyl acetate solution of polyester, one pass was performed under the same conditions to obtain a raw material dispersion. The obtained raw material dispersion had a solid content concentration of 50% by mass by heating at 130 ° C. for 30 minutes.

  In a reaction vessel, 749 parts of a raw material dispersion, 115 parts of a polyester prepolymer and 1.45 parts of isophorone diamine are charged, and using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) for 1 minute at 7.5 m / second. The toner material liquid was obtained by mixing.

  To the obtained toner material liquid, 1200 parts of an aqueous medium was added and mixed for 20 minutes at a peripheral speed of 15 m / sec using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain an emulsified slurry.

  The emulsified slurry was charged into a reaction vessel equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, the mixture was aged at 45 ° C. for 4 hours to obtain a dispersed slurry.

  100 parts of the dispersion slurry was filtered under reduced pressure. 100 parts of ion-exchanged water was added to the obtained filter cake, and the mixture was mixed for 10 minutes at 10.0 m / sec using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), followed by filtration. After adding 100 parts of ion-exchanged water to the obtained filter cake, the mixture was mixed at 10.0 m / sec for 10 minutes using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) and then filtered under reduced pressure. After adding 100 parts of 10 mass% sodium hydroxide aqueous solution to the obtained filter cake, it was mixed for 10 minutes at 10.0 m / sec using a TK type homomixer (manufactured by Koki Kogyo Co., Ltd.) and then filtered. . After adding 300 parts of ion-exchanged water to the obtained filter cake, using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), mixing at 10.0 m / second for 10 minutes, and then filtering twice. And a filter cake was obtained. The obtained filter cake was dried for 48 hours at 45 ° C. using a circulating dryer, and then sieved with a mesh of 75 μm to obtain a toner (matrix particles). The obtained toner had an average circularity of 0.97, a volume average particle diameter of 6 μm, and a content of components having a particle diameter of 25 μm or more was 0.4% by mass.

[Example 2]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of paraffin wax and microcrystalline wax was changed to 7:93. The obtained toner had an average circularity of 0.96, a volume average particle diameter of 5 μm, and a content of components having a particle diameter of 25 μm or more was 0.5% by mass.

[Example 3]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of paraffin wax and microcrystalline wax was changed to 10:90. The obtained toner had an average circularity of 0.97, a volume average particle size of 6 μm, and a content of components having a particle size of 25 μm or more was 0.1% by mass.

[Example 4]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of the paraffin wax and the microcrystalline wax was changed to 12:88. The obtained toner had an average circularity of 0.97, a volume average particle size of 6 μm, and a content of components having a particle size of 25 μm or more was 0.3% by mass.

[Example 5]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of the paraffin wax and the microcrystalline wax was changed to 15:85. The obtained toner had an average circularity of 0.96, a volume average particle size of 5 μm, and a content of components having a particle size of 25 μm or more was 0.2% by mass.

[Comparative Example 1]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of the paraffin wax and the microcrystalline wax was changed to 100: 0. The obtained toner had an average circularity of 0.97, a volume average particle size of 6 μm, and a content of components having a particle size of 25 μm or more was 0.6% by mass.

[Comparative Example 2]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of the paraffin wax and the microcrystalline wax was changed to 0: 100. The obtained toner had an average circularity of 0.97, a volume average particle diameter of 6 μm, and a content of components having a particle diameter of 25 μm or more was 0.4% by mass.

[Comparative Example 3]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of the paraffin wax and the microcrystalline wax was changed to 40:60. The obtained toner had an average circularity of 0.97, a volume average particle size of 5 μm, and a content of components having a particle size of 25 μm or more was 0.1% by mass.

[Comparative Example 4]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of paraffin wax and microcrystalline wax was changed to 20:80. The obtained toner had an average circularity of 0.97, a volume average particle size of 6 μm, and a content of components having a particle size of 25 μm or more was 0.3% by mass.

[Comparative Example 5]
A toner was obtained in the same manner as in Example 1 except that the mass ratio of paraffin wax and microcrystalline wax was changed to 3:97. The obtained toner had an average circularity of 0.96, a volume average particle size of 5 μm, and a content of components having a particle size of 25 μm or more was 0.2% by mass.

[Comparative Example 6]
A toner was obtained in the same manner as in Comparative Example 1 except that Barico BW3250 (manufactured by Toyo Adre) having a melting point of 76 ° C. was used as the paraffin wax. The obtained toner had an average circularity of 0.96, a volume average particle size of 5 μm, and a content of components having a particle size of 25 μm or more was 0.3% by mass.

[Comparative Example 7]
A toner was obtained in the same manner as in Comparative Example 2 except that Victory Amber (manufactured by Toyo Adre) having a melting point of 79 ° C. and a mass reduction of 2.1% at 165 ° C. was used as the microcrystalline wax.

  Using each developer thus obtained, (a) dust generation and (b) releasability during fixing were measured as follows. The obtained toner had an average circularity of 0.96, a volume average particle size of 5 μm, and a content of components having a particle size of 25 μm or more was 0.4% by mass.

[Melting point of wax]
The melting point of the wax was measured using TA-60WS and DSC-60 (manufactured by Shimadzu Corporation). Specifically, 5 mg of wax was packed in an aluminum sample pan, and the melting point was measured under the following temperature conditions under a nitrogen atmosphere with a nitrogen flow rate of 50 ml / min.

Starting temperature: 20 ° C
Rate of temperature increase: 10 ° C / min End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min End temperature: 20 ° C
Holding time: None Temperature increase rate: 10 ° C / min Ending temperature: 150 ° C
As a reference, an aluminum sample pan was used. The measurement results were analyzed using data analysis software TA-60, version 1.52 (manufactured by Shimadzu Corporation).

[Weight loss of wax at 165 ° C.]
The mass reduction | decrease in 165 degreeC of wax was measured using TA-60WS and DTG-60 (made by Shimadzu Corp.). Specifically, 5 mg of wax was packed in an aluminum sample pan, and the melting point was measured under the following temperature conditions under a nitrogen atmosphere with a nitrogen flow rate of 50 ml / min.

Starting temperature: 20 ° C
Rate of temperature increase: 10 ° C / min End temperature: 165 ° C
Holding time: 60 minutes In addition, the sample pan made from aluminum was used as a reference. The measurement results were analyzed using data analysis software TA-60, version 1.52 (manufactured by Shimadzu Corporation).

[Average circularity of toner]
The average circularity of the toner was measured using a flow type particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation). Specifically, after adding 100 to 150 ml of water from which impure solids have been removed in advance and 0.1 to 0.5 ml of a surfactant alkylbenzene sulfonate, about 0.1 to 0.5 g of toner is added. did. Next, after dispersing for about 1 to 3 minutes using an ultrasonic disperser, the toner density was adjusted to 3000 to 10,000 / μl, and the average circularity of the toner was measured.

[Toner particle size distribution]
The particle size distribution of the toner was measured using a particle size measuring device Coulter Counter TAII (manufactured by Coulter Electronics). Specifically, first, 0.1 to 5 ml of a surfactant alkylbenzene sulfonate was added to 100 to 150 ml of about 1% by mass aqueous sodium chloride solution, and then 2 to 20 mg of toner was added. Next, after dispersing for about 1 to 3 minutes using an ultrasonic disperser, the particle size distribution of the toner was measured using a 100 μm aperture.

  The channel is 2.00 μm or more and less than 2.52 μm, 2.52 μm or more and less than 3.17 μm, 3.17 μm or more and less than 4.00 μm, 4.00 μm or more and less than 5.04 μm, 5.04 μm or more and less than 6.35 μm. 6.35 μm to less than 8.00 μm, 8.00 μm to less than 10.08 μm, 10.08 μm to less than 12.70 μm, 12.70 μm to less than 16.00 μm, 16.00 μm to less than 20.20 μm, 20.20 μm or more 13 channels of less than 25.40 μm, 25.40 μm or more and less than 32.00 μm and 32.00 μm or more and less than 40.30 μm were used, and particles having a particle size of 2.00 μm or more and less than 40.30 μm were measured.

[Dispersion of dust]
The toner of the example or the comparative example is accommodated in the developing device of the color electrophotographic apparatus RICOH Pro C900 (manufactured by Ricoh), and the dust is measured using the measurement method described in Blue Angel (RAL-UZ62, 85, 114). The emission rate of was measured. It should be noted that the case where the dust release rate is 4 mg / hour or more is 1, 3 mg / hour or more and less than 4 mg / hour, 2, the case where it is 2 mg / hour or more and less than 3 mg / hour is 3, 3 mg / hour or more and 2 mg or more. The case of less than 4 hours / hour was determined as 4, and the case of less than 1 mg / hour was determined as 5.

[Releasability at low temperature fixing (separation resistance)]
The separation resistance was measured using the measuring apparatus 10 (see FIG. 1). Specifically, a fixing roller R1 immediately after the fixing nip N formed between the fixing roller R1 and the heating and pressure roller R2 of the fixing device of the color electrophotographic apparatus RICOH Pro C900 (manufactured by Ricoh) is provided. The detection claw 11 was installed on the side, the temperature of the fixing roller R1 was set to 160 ° C., the paper S on which the toner of the example or comparative example was adhered was fixed, and the separation resistance was measured. At this time, the sheet S that has passed through the fixing nip N is conveyed while being wound around the fixing roller R1, and is thus pressed against the detection claw 11. The force F pressed against the detection claw 11 is read by the load cell 12 provided at the other end of the detection claw 11. This value is a force necessary to separate the paper S from the fixing roller R1, and is defined as a separation resistance force.

  The evaluation results are shown in Table 1.

表１より、実施例１〜５のトナーを用いると、粉塵の放散速度が小さく、低温定着時の離型性が優れることがわかる。一方、比較例１、３、４のトナーを用いると、粉塵の放散速度が大きくなる。また、比較例２、５のトナーを用いると、低温定着時の離型性が劣る。さらに、比較例６、７から、高融点のパラフィンワックス又は低融点のマイクロクリスタリンワックスを用いても、比較例１、２と同様の問題があることがわかる。

From Table 1, it can be seen that when the toners of Examples 1 to 5 are used, the dust diffusion rate is small and the releasability at low temperature fixing is excellent. On the other hand, when the toners of Comparative Examples 1, 3, and 4 are used, the dust diffusion rate increases. Further, when the toners of Comparative Examples 2 and 5 are used, the releasability at low temperature fixing is poor. Furthermore, it can be seen from Comparative Examples 6 and 7 that the same problems as in Comparative Examples 1 and 2 occur even when a high melting point paraffin wax or a low melting point microcrystalline wax is used.

JP 2007-241092 A

Claims (16)

A toner having base particles including a binder resin, a colorant, paraffin wax, microcrystalline wax and inorganic particles,
A toner, wherein a ratio of a mass of the paraffin wax to a total mass of the paraffin wax and the microcrystalline wax is 5% or more and 15% or less.   The toner according to claim 1, wherein the paraffin wax has a melting point of 65 ° C. or higher and 85 ° C. or lower.   The toner according to claim 1, wherein the microcrystalline wax has a melting point of 60 ° C. or higher and 90 ° C. or lower.   The toner according to claim 1, wherein the microcrystalline wax has a mass loss at 165 ° C. of 10% or less.   The toner according to claim 1, wherein the total content of the paraffin wax and the microcrystalline wax is 2% by mass or more and 10% by mass or less.   The toner according to claim 1, wherein the inorganic particles are silica that has been subjected to a hydrophobic treatment.   The toner according to claim 1, wherein the average circularity is 0.94 or more and 0.98 or less. The volume average particle size is 3 μm or more and 8 μm or less,
The toner according to claim 1, wherein the content of a component having a particle diameter of 25 μm or more is 0.5% by mass or less.   The toner according to claim 1, wherein the binder resin includes urea-modified polyester.   The toner according to claim 9, wherein the binder resin further includes polyester.   The toner according to claim 1, wherein the base particles further include resin particles. A step of preparing a first liquid by dissolving or dispersing a toner material containing a polyester prepolymer having an isocyanate group, a compound having an amino group, a colorant, paraffin wax, microcrystalline wax and inorganic particles in an organic solvent;
A step of preparing a second liquid by emulsifying or dispersing the first liquid in an aqueous medium containing resin particles;
Removing the organic solvent from the second liquid,
A toner production method, wherein a ratio of a mass of the paraffin wax to a total mass of the paraffin wax and the microcrystalline wax is 5% or more and 15% or less.   The method of manufacturing a toner according to claim 12, wherein the toner material further includes polyester.   The toner production method according to claim 13, wherein a ratio of a mass of the polyester prepolymer to a total mass of the polyester and the polyester prepolymer is 5% or more and 25% or less.   A developer comprising the toner according to claim 1. Charging the photoreceptor,
Exposing the charged photoreceptor to form an electrostatic latent image;
Developing the electrostatic latent image formed on the photoreceptor with the developer according to claim 15 to form a toner image;
Transferring the toner image formed on the photoreceptor to a recording medium;
An image forming method comprising a step of fixing a toner image transferred to the recording medium.

Images