JP6676290B2 - Manufacturing method of toner - Google Patents

Description

  The present invention relates to a method for producing a toner used in a method such as an electrophotographic method, an electrostatic recording method, and a toner jet recording method.

  2. Description of the Related Art In recent years, lower power consumption has been required for printers and copiers. Regarding the performance of toner, it is required to soften the toner at a lower temperature. To address this problem, a toner to which a crystalline resin is added has been studied. The crystalline resin has a lower viscosity when melted than the amorphous resin, and can soften the toner at a lower temperature.

  Patent Documents 1 to 3 disclose a suspension polymerization toner using a crystalline polyester. It is described that in the above toner, the use of crystalline polyester improves the low-temperature fixability of the toner.

JP 2006-106727 A JP 2009-063969 A JP 2013-80112 A

  However, as a result of the study by the present inventors, when a crystalline resin is simply added in the suspension polymerization method, a problem that a part of the crystalline resin is exposed on the toner surface, and the chargeability and fluidity are reduced. May occur. Examination of the toner disclosed in Patent Document 1 reveals that although crystalline polyester is present in the surface layer and inside, excellent low-temperature fixability can be obtained, but the chargeability and fluidity are liable to decrease. Also in the toners described in Patent Documents 2 and 3, since the presence state of the crystalline polyester in the toner is not controlled, the crystalline polyester is partially exposed on the toner surface, and sufficient chargeability and fluidity are obtained. It was not possible. Therefore, there has not been proposed a toner obtained by controlling the exposure of the crystalline resin on the toner surface and achieving both low-temperature fixability and excellent chargeability and fluidity in the suspension polymerization toner into which the crystalline resin is introduced.

  An object of the present invention is to provide a method for producing a toner which is excellent in low-temperature fixability and further excellent in chargeability and fluidity.

The present invention is a method for producing a toner having toner particles,
The production method
A granulation step of forming particles of a composition containing a polymerizable monomer, an amorphous polyester resin and a crystalline polyester resin in an aqueous medium to obtain a suspension,
Polymerization step of polymerizing the polymerizable monomer contained in the particles of the composition in the suspension, and,
Adjusting the pH of the aqueous medium in the suspension to 6.0 or more and 10.0 or less, and heating the temperature of the aqueous medium to or higher than the glass transition temperature of the amorphous polyester resin;
The includes the step of forming the toner particles through,
The acid value of the non-crystalline polyester resin is a method for producing a toner, wherein the higher than the acid value of the crystalline polyester resin.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the toner which is excellent in low-temperature fixing property, and also excellent in chargeability and fluidity can be provided.

FIG. 2 is a schematic view of an apparatus used for measuring a charge amount of the present invention.

  The method for producing a toner of the present invention has the following two steps as a suspension polymerization method. One is a granulation step in which particles of a composition containing a polymerizable monomer, an amorphous resin, and a crystalline resin are formed in an aqueous medium to obtain a suspension. The other is a polymerization step of polymerizing a polymerizable monomer contained in the particles of the composition in the suspension. In the present invention, the pH of the aqueous medium in the suspension is adjusted to 6.0 or more and 10.0 or less, and the temperature of the aqueous medium is heated to the glass transition temperature or more of the amorphous resin. It is characterized in that the acid value of the resin is higher than the acid value of the crystalline resin. Through these steps, toner particles can be formed.

  The present inventors have focused on a change in hydrophilicity due to dissociation (deprotonation) of a polar group contained in an amorphous resin and a crystalline resin in order to suppress the exposure of the crystalline resin to the toner surface. In the present invention, the acid value of the amorphous resin is higher than the acid value of the crystalline resin. At this time, the polar group that gives the amorphous resin and the crystalline resin an acid value is not particularly limited, but a carboxy group is preferable. In the following description, a case where a carboxy group is used will be described as a specific example.

  In general, a carboxy group dissociates in water to be anionized, thereby increasing hydrophilicity. It is known that the rate at which carboxy groups are dissociated also changes depending on the hydrogen ion concentration index (pH) of the aqueous medium. The lower the pH, the lower the rate at which the carboxy group dissociates, and the higher the pH, the higher the rate at which the carboxy group dissociates. This is the same for the carboxy group contained in the resin.

  The method for producing a toner by the suspension polymerization method in the present invention includes a granulation step and a polymerization step. At this time, the interface between the particles of the composition obtained by the granulation step and the aqueous medium and the interface between the particles obtained by polymerizing the polymerizable monomer contained in the particles and the aqueous medium are partially Are considered to exist.

  Therefore, the present inventors controlled the pH of the aqueous medium, thereby controlling the hydrophilicity of the amorphous resin and the crystalline resin present at the interface of the particles with the aqueous medium, and selectively controlling the amorphous resin. Was transferred to the outermost surface of the toner to suppress the exposure of the crystalline resin. The means is to make the acid value of the amorphous resin higher than the acid value of the crystalline resin and raise the pH of the aqueous medium at the time of toner production (6.0 or more and 10.0 or less). It is believed that this makes it possible to control the transferability of the amorphous resin to the toner surface and to control the exposure of the crystalline resin to the toner surface. This is because by setting the acid value to the above condition, the amorphous resin becomes more hydrophilic than the crystalline resin due to the dissociation of the carboxy group when the pH of the aqueous medium is increased, and the amorphous resin becomes It is presumed that the transfer to the aqueous medium side (the transfer to the toner surface) is promoted.

  Further, by performing a heat treatment at a temperature equal to or higher than the glass transition temperature (Tg) of the amorphous resin in the state where the acid value and the pH are set as described above, the molecular movement of the amorphous resin is promoted, and the amorphous resin is present on the toner surface. The amorphous resin and the crystalline resin can be rearranged. As a result, the amorphous resin having a large influence of the dissociation of the carboxy group is positively segregated on the outermost surface of the toner, and the crystalline resin having a small influence of the dissociation of the carboxy group is moved inward of the toner as compared with the amorphous resin. Can be moved.

  As described above, it is possible to significantly suppress the influence of the surface exposure of the crystalline resin on the toner performance such as chargeability and fluidity while obtaining the low-temperature fixing effect of the crystalline resin.

  When the pH of the aqueous medium is less than 6.0, the dissociation of the carboxy groups of the amorphous resin and the crystalline resin does not sufficiently occur, so that it is difficult to control the toner surface as described above. If the pH of the aqueous medium is higher than 10.0, the hydrophilicity of not only the amorphous resin but also the crystalline resin may be significantly increased. Is difficult to segregate. In addition, since the heat treatment is performed in a state where the amount of the crystalline resin exposed on the toner surface is large, coalescence of the toner particles occurs during the heat treatment, so that the production stability may be reduced. The pH of the aqueous medium is preferably 6.5 or more and 10.0 or less, more preferably 7.5 or more and 9.0 or less.

  Further, the aqueous medium in the suspension was adjusted to pH 6.0 or more and 10.0 or less, and the temperature of the aqueous medium was heated to Tg or more of the amorphous resin (hereinafter, also referred to as high pH and heat treatment). The effect of the present invention can be obtained even when the pH is lowered to 6.0 or less. This means that even if the pH is lowered to 6.0 or less and the proportion of dissociated carboxy groups is reduced, only the difference in hydrophilicity between the amorphous resin and the crystalline resin is reduced. It is presumed that this is because the permutation of hydrophilicity between the polymer and the crystalline resin is not reversed.

  The pH of the aqueous medium can be controlled by adding a known acid and alkali to the aqueous medium of the suspension. Specific examples include acids such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, citric acid, and phosphoric acid, and alkalis such as sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonia, and amine compounds.

  When the temperature of the aqueous medium is lower than the Tg of the amorphous resin, the amorphous resin hardly moves, and the amorphous resin and the crystalline resin existing on the toner surface are hardly rearranged. As the temperature of the aqueous medium, it is more preferable to heat the amorphous resin to a temperature equal to or higher than Tg of the amorphous resin + 20 ° C. In the present invention, the aqueous medium is preferably water, and the upper limit of the heating temperature is preferably 100 ° C. or lower, which is the boiling point of water.

  The time for performing the high pH and heat treatment is preferably 2 hours or more, and more preferably 3 hours or more. When the time is 3 hours or more, the amorphous resin can be sufficiently moved, and the resin existing on the toner surface can be controlled. The treatment may be performed for any time as long as it is 3 hours or more, but is preferably 20 hours or less from the viewpoint of productivity.

  In the present invention, the acid value of the amorphous resin is higher than the acid value of the crystalline resin. Thereby, the transferability of the amorphous resin to the toner surface can be controlled, and the exposure of the crystalline resin to the toner surface can be suppressed. The acid value of the amorphous resin is preferably from 1.0 mgKOH / g to 20.0 mgKOH / g. When the pH is 1.0 mg KOH or more, the effect of hydrophilization due to acid dissociation when the pH is increased is sufficiently obtained, and the amorphous resin can be segregated by the outermost layer of the toner. Further, since more amorphous resin can be present at the interface between the particles of the composition obtained by the granulation step and the aqueous medium, the pH should be set to 6.0 or more and 10.0 or less. The effect can be increased. Furthermore, since the amorphous resin has high hydrophilicity, the interfacial tension between the particles of the composition and the aqueous medium can be appropriately controlled, and the productivity is good. Further, when the content is 20.0 mgKOH / g or less, the hygroscopicity of the amorphous resin can be suppressed, and when the amorphous resin is segregated on the outermost surface of the toner, excellent charge can be obtained even under high temperature and high humidity. Sex can be obtained. The acid value of the amorphous resin is more preferably from 1.5 mgKOH / g to 15.0 mgKOH / g.

  The acid value of the crystalline resin is preferably 50.0% or less based on the acid value of the amorphous resin. When the content is 50.0% or less, the hydrophilicity of the crystalline resin can be controlled to be lower than that of the amorphous resin. Further, the influence of acid dissociation when the pH is set to 6.0 or more and 10.0 or less on the crystalline resin can be made smaller than that of the amorphous resin. Therefore, exposure of the crystalline resin to the toner surface can be sufficiently suppressed. The acid value of the crystalline resin is more preferably 25.0% or less based on the acid value of the amorphous resin. The specific acid value of the crystalline resin is preferably from 0 mgKOH / g to 6.0 mgKOH / g.

  The method of controlling the acid value of the amorphous resin and the crystalline resin differs depending on the resins constituting the amorphous resin and the crystalline resin. When the amorphous resin and the crystalline resin are polyester resins, for example, they can be controlled by the following method. That is, the ratio of the acid monomer and the alcohol monomer when producing the amorphous resin and the crystalline resin, the molecular weight, the amount of the monovalent acid monomer and / or the alcohol monomer, and the amount of the trivalent acid monomer and / or the alcohol monomer It can be controlled under such conditions. When the amorphous resin and the crystalline resin are styrene-acrylic resins, they can be controlled by conditions such as the amount of a monomer having a carboxyl group such as acrylic acid or methacrylic acid. The method for measuring the acid value of the amorphous resin and the crystalline resin will be described later.

  Further, the content of the amorphous resin in the toner is preferably 0.5% by mass or more and 10.0% by mass or less. When the content of the amorphous resin is 0.5% by mass or more, the surface of the toner can be sufficiently covered with the amorphous resin. As a result, exposure of the crystalline resin can be suppressed, and excellent charging properties can be obtained. Further, since the interfacial tension between the particles of the composition during granulation and the aqueous medium can be controlled, the production stability is good. When the content is 10.0% by mass or less, it is possible to suppress the influence on the fixability caused by coating the toner surface with the amorphous resin, and to obtain the fixing performance sufficiently utilizing the low-temperature fixability of the crystalline resin. be able to. The method for measuring the content of the amorphous resin will be described later.

  Further, the content of the crystalline resin in the toner is preferably 0.5% by mass or more and 20.0% by mass or less. Within this range, charging properties and low-temperature fixability are preferred.

  The composition of the amorphous resin is not particularly limited, and examples thereof include a styrene acrylic resin, a polyester resin, an epoxy resin, and a urethane resin. Similarly, the composition of the crystalline resin is not particularly limited, and examples thereof include crystalline polyester and crystalline acrylic resin.

  Among them, from the viewpoint of controlling segregation on the outermost surface of the toner due to pH, a polyester resin having an ester bond, which is a hydrophilic functional group, in the main chain is preferable for both the amorphous resin and the crystalline resin. By being a polyester resin, more amorphous resin can be present at the interface of the particles of the composition obtained by the granulation step with the aqueous medium, so that the pH is 6.0 or more and 10.0 or more. The effect of the following is greater. Further, a part of the polyester resin may be modified with another resin, and a block polymer or a graft polymer may be used.

  In the present invention, the crystalline resin refers to a resin having a clear endothermic peak (melting point) in a reversible specific heat change curve of a specific heat change measurement by a differential scanning calorimeter described later. On the other hand, a resin having no clear endothermic peak is an amorphous resin. In addition, the crystalline resin may be a block polymer in which a portion having a crystalline structure and a portion having an amorphous structure are bonded.

  In addition, a general definition of a block polymer is a polymer composed of a plurality of blocks connected in a line (a term used in the basic terminology of polymer science by the Society of Polymer Science, International Union of Pure and Applied Chemistry, Polymer Nomenclature Committee). ), And the present invention follows that definition.

  It is preferable that the amorphous resin and the crystalline resin have a functional group having an acid dissociation constant (pKa) in water of 4.0 or more and 9.0 or less as a functional group that imparts an acid value. When the pKa is 4.0 or more and 9.0 or less, it becomes easy to control the dissociation state of the acid depending on the pH of the suspension. Further, when the content is within the above range, the hygroscopicity of the amorphous resin and the crystalline resin can be suppressed, so that more excellent charging properties can be obtained even under high temperature and high humidity as a toner. The range of pKa can be controlled by the type of monomer used for producing the amorphous resin and the crystalline resin, and physical properties such as the molecular weight of the amorphous resin and the crystalline resin. The method for measuring pKa will be described later.

  The amorphous resin preferably has a Tg of 55 ° C. or more and 80 ° C. or less. This is because, in the present invention, the aqueous medium is preferably water, and the upper limit of the heat treatment temperature is 100 ° C., which is the boiling point of water. The Tg of the amorphous resin can be controlled by the type of the monomer constituting the amorphous resin. The method for measuring the Tg of the amorphous resin will be described later.

  The weight average molecular weight (Mw) of the amorphous resin is preferably from 9000 to 18,000. When the content is in the above range, sufficient hardness can be obtained, so that excellent fluidity as a toner can be obtained. Further, since the viscosity at the time of melting is low, the amorphous resin can be positively segregated on the toner surface when the pH is changed and heat treatment is performed.

  The weight average molecular weight (Mw) of the crystalline resin is preferably 10,000 or more and 35,000 or less. Within the above range, the crystalline resin can be positively moved inward of the toner when the pH is changed and the heat treatment is performed, while the viscosity is sufficiently reduced during melting. More preferably, the Mw of the crystalline resin is from 15,000 to 30,000.

  The weight average molecular weight (Mw) of the amorphous resin and the crystalline resin can be controlled by conditions such as a polymerization temperature and a polymerization time when producing the amorphous resin and the crystalline resin. The method for measuring the weight average molecular weight (Mw) of the amorphous resin and the crystalline resin will be described later.

  When the amorphous resin is a polyester resin, the polyester resin is obtained by polymerization of an alcohol monomer and a carboxylic acid monomer. Specific examples of the alcohol monomer include the following. Alcohol monomers such as ethylene glycol, diethylene glycol and 1,2-propylene glycol; dihydric alcohols such as polyoxyethylenated bisphenol A; aromatic alcohols such as 1,3,5-trihydroxymethylbenzene, and pentaerythritol Trihydric alcohol. As specific carboxylic acid monomers, for example, the following can be used. Dicarboxylic acids such as oxalic acid, sebacic acid, terephthalic acid, isophthalic acid and anhydrides or lower alkyl esters of these acids; trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid Trivalent or higher polyvalent carboxylic acids such as, for example, pyromellitic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, and 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane Acid components and their derivatives such as acid anhydrides or lower alkyl esters.

  For the purpose of controlling the terminal acid value and hydroxyl value so as not to impair the properties of the polyester resin, a monovalent carboxylic acid component or a monovalent alcohol component may be used. For example, benzoic acid, naphthalenecarboxylic acid, salicylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, phenoxyacetic acid, biphenylcarboxylic acid, acetic acid, propionic acid, butyric acid, octanoic acid, decanoic acid, dodecanoic acid, stearic acid, etc. Monocarboxylic acid. Also, n-butanol, isobutanol, sec-butanol, n-hexanol, n-octanol, lauryl alcohol, 2-ethylhexanol, decanol, cyclohexanol, benzyl alcohol, dodecyl alcohol.

  When the crystalline resin is a polyester resin, it is preferably obtained by reacting an aliphatic diol having 4 to 20 carbon atoms with an aliphatic dicarboxylic acid. Specifically, for example, the following can be used as the aliphatic diol. 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, , 11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol. Further, an aliphatic diol having a double bond can also be used. Specific examples of the aliphatic diol having a double bond include the following. 2-butene-1,4-diol, 3-hexene-1,6-diol, 4-octene-1,8-diol.

  Specific examples of the aliphatic dicarboxylic acid include the following. Oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid. Or its lower alkyl ester or acid anhydride. A dicarboxylic acid having a double bond can also be used. Specifically, for example, fumaric acid, maleic acid, 3-hexenedioic acid, and 3-octenedioic acid. In addition, these lower alkyl esters and acid anhydrides are also included.

  Next, the method for producing the toner of the present invention will be specifically described by exemplifying procedures and materials that may be used, but is not limited thereto.

  A polymerizable monomer, an amorphous resin, a crystalline resin, and a colorant are added, and the mixture is melted, dissolved or dispersed using a disperser such as a homogenizer, a ball mill, a colloid mill, or an ultrasonic disperser. A monomer composition is prepared. At this time, in the polymerizable monomer composition, if necessary, a release agent and a polyfunctional monomer, a pigment dispersant, a charge control agent, a solvent for adjusting viscosity, and other additives (For example, a chain transfer agent) may be appropriately added.

  Next, the polymerizable monomer composition is charged into an aqueous medium containing a dispersion stabilizer prepared in advance, and the polymerizable monomer is added using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser. A suspension is obtained by forming particles of the body composition (granulation step).

  The polymerization initiator may be mixed with other additives when preparing the polymerizable monomer composition, or may be mixed into the polymerizable monomer composition immediately before being suspended in the aqueous medium. Good. Also, during or after granulation, that is, immediately before the start of the polymerization reaction, it can be added in a state of being dissolved in a polymerizable monomer or another solvent, if necessary.

  The suspension after granulation is heated, and the particles of the monomer composition in the suspension maintain the particle state, and the polymerizable monomer is stirred while stirring so that the particles do not float or settle. A polymerization reaction is performed (polymerization step). Thereafter, an aqueous dispersion of toner particles is formed by performing a solvent removal treatment as necessary. In addition, a binder resin is obtained by polymerizing a polymerizable monomer.

  The high pH and heat treatment of the present invention may be performed at any stage after the above-mentioned granulation step. Thereafter, the toner is washed as required, and dried, classified, and externally added by various methods to obtain a toner.

  As the polymerizable monomer used in the present invention, a vinyl monomer capable of radical polymerization can be used. As the vinyl monomer, a monofunctional monomer or a polyfunctional monomer can be used.

Monofunctional monomers include styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-methylstyrene tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, and p-phenyl Styrene derivatives such as styrene;
Methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate Acrylic monomers such as n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and 2-benzoyloxyethyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate Methacrylic monomers such as n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate;
Polyfunctional monomers include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, and polypropylene. Glycol diacrylate, 2,2′-bis (4- (acryloxydiethoxy) phenyl) propane, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, Tetraethylene glycol dimethacrylate, polyethylene glycol dimethate Acrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2′-bis (4- (methacryloxydiethoxy) phenyl) propane, 2,2′-bis (4- (methacryloxypolyethoxy) phenyl) propane, trimethylolpropane trimethacrylate, tetramethylolmethanetetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether are exemplified.

  With respect to the above monomers, a monofunctional monomer alone or in combination of two or more, or a monofunctional monomer and a polyfunctional monomer in combination, or a polyfunctional monomer alone, or two or more Can be used in combination.

  In the toner of the present invention, known colorants such as various dyes and pigments conventionally known as colorants can be used.

  As the black colorant, a carbon black, a magnetic substance, or a substance toned to black using a yellow / magenta / cyan colorant shown below is used. As a colorant for cyan toner, magenta toner, and yellow toner, for example, the following colorants can be used.

  Examples of the yellow colorant include pigments such as monoazo compounds, disazo compounds, condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complex methine compounds, and allylamide compounds. Specifically, C.I. I. Pigment Yellow 74, 93, 95, 109, 111, 128, 155, 174, 180, and 185.

  As the magenta coloring agent, a monoazo compound, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound, and a perylene compound are used. Specifically, C.I. I. Pigment Red 2,3,5,6,7,23,48: 2,48: 3,48: 4,57: 1,81: 1,122,144,146,150,166,169,177,184. 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. Pigment Bio Red 19 and the like.

  As the cyan coloring agent, a copper phthalocyanine compound and its derivative, an anthraquinone compound, and a basic dye lake compound can be used. Specifically, C.I. I. Pigment Blue 1,7,15,15: 1,15: 2,15: 3,15: 4,60,62,66.

  The colorant is preferably contained in the toner in an amount of 1.0% by mass to 20.0% by mass.

  When the toner of the present invention is used as a magnetic toner, a magnetic material may be contained in the toner particles. In this case, the magnetic material can also serve as a colorant. In the present invention, examples of the magnetic substance include iron oxides such as magnetite, hematite and ferrite; and metals such as iron, cobalt and nickel. Or alloys of these metals with metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium and mixtures thereof. .

  The release agent that can be used in the present invention is not particularly limited, and a known release agent can be used. For example, the following compounds may be mentioned. Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, paraffin wax, Fischer-Tropsch wax; aliphatic hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof; carnauba Wax containing fatty acid ester as a main component such as wax, sasol wax, ester wax, montanic acid ester wax; Deoxidized partially or entirely of fatty acid ester such as deoxidized carnauba wax; Aliphatic hydrocarbon wax Waxes grafted with vinyl monomers such as styrene and acrylic acid; partially esterified products of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; obtained by hydrogenation of vegetable fats and oils And methyl ester compounds having a Dorokishiru group. The release agent is preferably contained in the toner in an amount of 1.0% by mass to 20.0% by mass.

  Further, the toner particles of the present invention may use a charge control agent. Among them, it is preferable to use a charge control agent that controls the toner particles to be negatively charged. Examples of the charge control agent include the following.

  Organometallic compounds, chelate compounds, monoazo metal compounds, acetylacetone metal compounds, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, quaternary ammonium salts, calixarenes, silicon compounds, nonmetal carboxylic acid compounds and derivatives thereof Is mentioned. Further, a sulfonic acid resin having a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group can be preferably used.

  The added amount of the charge control agent is preferably 0.01% by mass to 20.0% by mass in the toner.

  Further, as a dispersion stabilizer to be added to the aqueous medium, an inorganic dispersant can be suitably used because it is difficult to generate an ultrafine powder, is easy to wash, and hardly affects the toner. The following are mentioned as an inorganic dispersing agent. Polyvalent metal phosphates such as tricalcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; inorganic salts such as calcium metasilicate, calcium sulfate and barium sulfate; Inorganic oxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite, and alumina. Among these inorganic dispersants, calcium phosphate, aluminum phosphate, magnesium phosphate, and aluminum hydroxide, which can be stably present in the range of pH 6.0 to pH 10.0, are particularly preferable. These dispersion stabilizers can be almost completely removed by adding and dissolving an acid or alkali after completion of the polymerization.

  It is preferable that a fluidity improver is externally added to the toner of the present invention in order to improve image quality. As the fluidity improver, inorganic fine powder such as silicic acid fine powder, titanium oxide, and aluminum oxide are preferably used. These inorganic fine powders are preferably subjected to a hydrophobizing treatment with a hydrophobizing agent such as a silane coupling agent, silicone oil or a mixture thereof. Further, in the toner of the present invention, an external additive other than the fluidity improver may be mixed with the toner particles as needed.

  The total amount of the inorganic fine particles is preferably from 1.0 to 5.0 parts by mass based on 100 parts by mass of the toner particles.

  The toner of the present invention can be used as it is as a one-component developer or as a two-component developer by mixing with a magnetic carrier.

  Hereinafter, a method for measuring each physical property value specified in the present invention will be described.

<Method for measuring acid value of amorphous resin and crystalline resin>
The acid value of each resin is measured according to JIS K1557-1970. A specific measuring method will be described below. In the present invention, the sample is an amorphous resin or a crystalline resin.

  2 g of a crushed sample is precisely weighed (W (g)). A sample is placed in a 200 ml Erlenmeyer flask, 100 ml of a mixed solution of toluene / ethanol (2: 1) is added, and the mixture is dissolved for 5 hours. At this time, you may heat as needed. Add phenolphthalein solution as indicator. The above solution is also titrated with a burette using a 0.1 mol / L KOH alcohol solution. The amount of the KOH solution at this time is defined as S (ml). A blank test is performed, and the amount of the KOH solution at this time is defined as B (ml).

Calculate the acid value by the following formula. Here, “f” in the equation is a factor of the KOH solution.
Acid value (mgKOH / g) = [(S−B) × f × 5.61] / W

<Method for measuring content of amorphous resin>
In order to measure the content of the amorphous resin, first, the amorphous resin is isolated from the toner, the NMR spectrum of the amorphous resin alone, and the binder resin component obtained by polymerization of the polymerizable monomer. Is measured.

(Isolation of amorphous resin)
5 g of the toner is dissolved in 100 g of toluene to prepare a toluene solution of the toner. Then, hexane is added to the toluene solution until a resin precipitate is obtained. When the resin precipitate is obtained, the addition of hexane is stopped, and the toluene solution is centrifuged. The precipitate obtained by centrifugation is collected and dried to obtain a solid content. The solid content obtained at this point is an amorphous resin and insolubles such as pigments and external additives.

  Further, the supernatant toluene solution obtained by the centrifugation was also collected, and toluene and hexane were evaporated to obtain a binder resin component.

  Next, the solid content is dissolved in 3 g of THF to prepare a THF solution of the precipitate. The THF solution was centrifuged to remove insoluble components such as pigments and external additives, the supernatant THF solution was collected, and THF was evaporated to obtain an amorphous resin.

(Measurement of NMR spectra of amorphous resin and binder resin component)
The NMR spectra of the amorphous resin and the binder resin component were measured using nuclear magnetic resonance spectroscopy (1H-NMR) [400 MHz, CDCl 3, room temperature (25 ° C.)].
Measurement device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0 μs
Frequency range: 10500Hz
Integration frequency: 64 times From the NMR spectrum measured by the method described above, a peak specific to the amorphous resin in the toner was identified.

(Measurement of content of amorphous resin)
The content of the amorphous resin was measured using nuclear magnetic resonance spectroscopy (1H-NMR) [400 MHz, CDCl3, room temperature (25 ° C.)].
Measurement device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0 μs
Frequency range: 10500Hz
Number of integration: 64 times The content of the amorphous resin was calculated from the integrated value of the spectrum of the toner obtained under the above conditions and the peak intensity unique to the amorphous resin described above.

<Method of measuring pKa of amorphous resin and crystalline resin>
0.100 g of the measurement sample is precisely weighed in a 250 ml tall beaker, 150 ml of THF is added, and dissolved for 30 minutes. A pH electrode is put in this solution, and the pH of the THF solution of the sample is read. Thereafter, 0.1 mol / l potassium hydroxide ethyl alcohol solution (manufactured by Kishida Chemical Co., Ltd.) is added in 10 μl portions, and the pH is read and titrated each time. A 0.1 mol / l potassium hydroxide ethyl alcohol solution is added until the pH becomes 10 or more and the pH does not change even if 30 μl is added. From the results obtained, the pH against the amount of the 0.1 mol / l potassium hydroxide ethyl alcohol solution added is plotted to obtain a titration curve. The point where the slope of the pH change is the largest from the obtained titration curve is defined as the neutralization point. Since the pKa is the same as the pH at half the amount of the 0.1 mol / l potassium hydroxide ethyl alcohol solution required until the neutralization point, the pH at the half amount is read from the titration curve.

<Method for measuring weight average molecular weight (Mw) of amorphous resin and crystalline resin>
The weight average molecular weight (Mw) of the amorphous resin and the crystalline resin is measured by gel permeation chromatography (GPC) as follows.

First, various resins are dissolved in tetrahydrofuran (THF). At this time, heating may be performed if necessary. Thereafter, the obtained solution is filtered through a solvent-resistant membrane filter “Maisho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: High-speed GPC apparatus "HLC-8220GPC" [Tosoh Corporation]
Column: LF-604 duplex [Showa Denko KK]
Eluent: THF
Flow rate: 0.6 ml / min
Oven temperature: 40 ° C
Sample injection volume: 0.020 ml
When calculating the molecular weight of the sample, a standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-20, 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation).

<Method of measuring glass transition temperature Tg (° C.) of amorphous resin and melting point Tm (° C.) of crystalline resin>
The glass transition temperature Tg (° C.) of the amorphous resin is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q1000” (manufactured by TA Instruments). The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat quantity correction uses the heat of fusion of indium. Specifically, 2 mg of the measurement sample was precisely weighed and placed in an aluminum pan, and an empty aluminum pan was used as a reference. Heat at a rate of minutes. Hold at 100 ° C. for 15 minutes, then cool at a rate of 10 ° C./min between 100 ° C. and 0 ° C. Hold at 0 ° C. for 10 minutes, then measure between 0 ° C. and 100 ° C. at a rate of 10 ° C./min. The peak value in the endothermic curve in the second heating process is defined as a melting point Tm (° C.). The intersection of the line at the middle point of the baseline and the differential heat curve before and after the specific heat change of the specific heat change curve in the second heating process is Tg (° C.).

<Measurement method of charge amount>
In the apparatus shown in FIG. 1, 0.5 g of the toner whose charge amount is to be measured is placed in a metal measuring container 2 having a 500-mesh screen 3 at the bottom, and a metal lid is placed. At this time, the mass of the entire measurement container 2 is weighed to be W1 (g). Next, in a suction machine (at least a portion in contact with the measurement container 2 is an insulator), the air is suctioned from the suction port 7 and the air volume control valve 6 is adjusted to adjust the pressure of the vacuum gauge 5 to 250 mmAq. In this state, suction is performed sufficiently, preferably for 2 minutes, to remove the toner by suction. The potential of the electrometer 9 at this time is set to V (volt). Here, reference numeral 8 denotes a capacitor whose capacity is C (mCF). The mass of the entire measurement container after the suction is weighed and defined as W2 (g). The charge amount (mC / kg) of this toner is calculated as in the following equation.
Charge amount (mC / kg) = (C × V) / (W1-W2)

<Method of measuring weight average particle diameter (D4)>
The weight average particle diameter (D4) of the toner is calculated as follows. As a measuring device, a precise particle size distribution measuring device “Coulter Counter Multisizer 3” (trade name, manufactured by Beckman Coulter, Inc.) equipped with a 100 μm aperture tube by a pore electric resistance method is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter) is used. The measurement is performed with 25,000 effective measurement channels. As the electrolytic aqueous solution used for the measurement, one prepared by dissolving a special grade sodium chloride in ion-exchanged water so as to have a concentration of 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter) can be used. Before performing the measurement and analysis, the dedicated software is set as follows.

  On the “Change Standard Measurement Method (SOM)” screen of the dedicated software, set the total count number in the control mode to 50,000 particles, set the number of measurements to 1, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter Set the value obtained by using the following method. By pressing the “threshold / noise level measurement button”, the threshold and the noise level are automatically set. Also, the current is set to 1600 μA, the gain is set to 2, and the electrolytic solution is set to ISOTON II, and a check is made in “Flush aperture tube after measurement”.

On the “pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set from 2 μm to 60 μm.
The specific measuring method is as follows.
(1) 200 mL of the electrolytic aqueous solution is placed in a glass 250 mL round bottom beaker for Multisizer 3 and set on a sample stand, and the stirrer rod is agitated counterclockwise at 24 revolutions / second. Then, the dirt and air bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) 30 mL of the electrolytic aqueous solution is put into a glass 100 mL flat bottom beaker. A 10% by mass aqueous solution of a neutral detergent for cleaning a precision measuring instrument having a pH of 7 comprising a nonionic surfactant, an anionic surfactant, and an organic builder as a dispersant is used as a dispersant therein, manufactured by Wako Pure Chemical Industries, Ltd. ) Is diluted by 3 times with ion-exchanged water, and 0.3 mL of a diluent is added.
(3) An ultrasonic disperser “Ultrasonic Dispersion System Tetora 150” (manufactured by Nikkaki Bios Co., Ltd.) having two oscillators having an oscillation frequency of 50 kHz and having a phase shifted by 180 degrees and having an electrical output of 120 W is prepared. 3.3 L of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and 2 mL of contaminone N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the aqueous electrolytic solution in the beaker becomes maximum.
(5) 10 mg of toner is added little by little to the electrolytic aqueous solution in the beaker of (4) in a state where the electrolytic aqueous solution is irradiated with ultrasonic waves, and dispersed. Then, the ultrasonic dispersion processing is continued for another 60 seconds. The ultrasonic dispersion is appropriately adjusted so that the water temperature of the water tank is 10 ° C. or more and 40 ° C. or less.
(6) The aqueous electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette into the round bottom beaker of (1) installed in the sample stand, and the measurement concentration is adjusted to 5%. . Then, measurement is performed until the number of particles to be measured reaches 50,000.
(7) Analyze the measured data with the dedicated software attached to the device, and calculate the weight average particle size (D4). The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4).

  Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples. All parts used in the examples are parts by mass. The toners 1 to 20 were manufactured as examples, and the toners 21 to 28 were manufactured as comparative examples.

<Production of amorphous resin 1>
To a reaction vessel equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dehydration tube, and a decompression device, was added 100.0 parts of a mixture in which raw material monomers other than trimellitic acid were mixed at the mol ratio shown in Table 1. The mixture was heated to a temperature of 130 ° C. while stirring. Thereafter, 0.52 parts of di (2-ethylhexanoic acid) tin is added as an esterification catalyst, the temperature is raised to 200 ° C., and polycondensation is performed until a desired molecular weight is reached. Further, trimellitic anhydride was added at a molar ratio shown in Table 1, and the resulting mixture was placed in a polymerization tank equipped with a nitrogen introduction line, a dehydration line, and a stirrer, and subjected to a condensation reaction under a reduced pressure of 40 kPa to obtain an amorphous resin 1. Obtained. The weight average molecular weight (Mw) of the amorphous resin 1 measured according to the method described above was 12000, the glass transition temperature (Tg) was 70 ° C., and the pKa was 6.0.

<Production of amorphous resins 2 to 8>
The same operation as in the case of the amorphous resin 1 was performed under the raw material monomer charge amounts and the temperature conditions of the polycondensation reaction shown in Table 1 to produce amorphous resins 2 to 8. Table 1 shows the physical properties of the obtained amorphous resins 2 to 8.

  In the table, TPA indicates terephthalic acid, TMA indicates trimellitic acid, and BPA-PO 2 mol adduct indicates bisphenol A propylene oxide 2 mol adduct.

<Production of crystalline resin 1>
To a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction tube, a dehydration tube, and a decompression device, was added 100.0 parts of a mixture obtained by mixing raw material monomers other than stearyl alcohol at a mol ratio shown in Table 2. Heated to a temperature of 130 ° C. with stirring. After adding 0.7 part of titanium (IV) isopropoxide as an esterification catalyst, the temperature was raised to 180 ° C., and the mixture was reacted under reduced pressure until a desired molecular weight was reached. Further, stearyl alcohol was added at a molar ratio shown in Table 2, and the mixture was placed in a polymerization tank equipped with a nitrogen introduction line, a dehydration line, and a stirrer, and reacted under reduced pressure of 40 kPa to obtain a crystalline resin 1. The weight average molecular weight (Mw) of the crystalline resin 1 measured according to the method described above was 20,000, and the melting point (Tm) was 74 ° C.

<Production of crystalline resins 2 to 5>
Crystalline resins 2 to 5 were obtained in the same manner as in the method for producing crystalline resin 1 except that the raw materials were changed to those shown in Table 2.

  Table 2 shows the physical properties of the obtained crystalline resins 1 to 5. It was confirmed that the crystalline resins 1 to 5 had a clear endothermic peak (melting point) in a reversible specific heat change curve of a specific heat change measurement by a differential scanning calorimeter.

<Production of Toner 1>
<Production process of aqueous dispersion medium>
To 1000 parts of ion-exchanged water in a reaction vessel, 14 parts of sodium phosphate (manufactured by Lhasa Industry Co., Ltd.) was charged, and the temperature was maintained at 65 ° C. for 60 minutes while purging with N 2. T. K. Using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), while stirring at 12000 rpm, an aqueous solution of calcium chloride in which 7.8 parts of calcium chloride is dissolved is added to 10 parts of ion-exchanged water at a time, and a dispersion stabilizer is contained. An aqueous medium was prepared. At this time, the pH of the aqueous medium was confirmed to be 10.8. Further, 4.5 parts of 10% hydrochloric acid was added to the aqueous medium to adjust the pH to 5.8.

<Manufacturing process of polymerizable monomer composition>
The following materials were put into a beaker, and mixed by stirring with a propeller type stirring device at a stirring speed of 100 rpm to prepare a mixed solution.
-67.5 parts of styrene-22.5 parts of n-butyl acrylate-6.0 parts of Pigment Blue 15: 3-1.0 part of aluminum salicylate compound (Bontron E-88: manufactured by Orient Chemical Co., Ltd.)
・ Release agent Paraffin wax 7.0 parts (HNP-9: Nippon Seiro, melting point 75 ° C)
-Amorphous resin 1 6.5 parts-Crystalline resin 1 10.0 parts Then, the mixture was heated to 65 ° C to obtain a polymerizable monomer composition.

<Suspension manufacturing process>
While maintaining the temperature of the aqueous medium at 70 ° C. and the rotation speed of the stirrer at 15,000 rpm, the polymerizable monomer composition was charged into the aqueous medium, and t-butyl peroxypivalate 9 as a polymerization initiator was added. 0.0 parts were added. The mixture was granulated at pH 5.8 for 10 minutes while maintaining 15,000 rotations / minute with a stirring device (granulation step).

<Production process of resin particle slurry>
The polymerization reaction is performed by maintaining the temperature at 70 ° C. for 5.0 hours while stirring at 150 rpm, replacing the stirrer with a propeller stirring blade from the high-speed stirring device, and then heating to 85 ° C. and heating for 2 hours. Was carried out to obtain a resin particle slurry (polymerization step).

<Heat treatment step>
An aqueous solution of sodium carbonate was added to the resin particle slurry obtained in the above step, and the pH of the resin particle slurry was adjusted to 8.0. Thereafter, the temperature of the resin particle slurry was raised to 98 ° C., and a heat treatment was performed for 3 hours.

<Washing, drying, classification, external addition process>
After the heat treatment, the slurry was cooled, hydrochloric acid was added to the cooled slurry to adjust the pH to 1.4, and the mixture was stirred for 1 hour to dissolve the calcium phosphate salt. Thereafter, the slurry was washed with 10 times the amount of water of the slurry, filtered and dried, and the particle size was adjusted by classification to obtain toner particles.

  Hydrophobic silica fine powder (primary particle diameter: 7 nm, BET specific surface area: 130 m 2 /) treated with 20% by mass of dimethyl silicone oil based on silica fine powder as an external additive to 100 parts of the toner particles g) 1.5 parts were mixed with a Mitsui Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at a stirring speed of 3000 rpm for 15 minutes to obtain Toner 1. The weight average molecular weight (Mw) of the toner 1 measured according to the method described above was 35,000, and the glass transition temperature (Tg) was 55 ° C.

<Production of Toners 2 to 28>
As shown in Table 3, in the same manner as in the manufacturing method of the toner 1, except that the type and the number of the amorphous resin, the type and the number of the crystalline resin, the pH, the temperature, and the heat treatment time of the heat treatment process were changed. Thus, toners 2 to 28 were obtained.

<Examples 1 to 20, Comparative Examples 1 to 8>
The performance of each of the obtained toners was evaluated according to the following method.

(Chargeability, environmental stability of chargeability)
The two-component developer is allowed to stand for 24 hours in an environment of normal temperature and normal humidity (23 ° C./60%), and then placed in a 50 cc plastic container and shaken 200 times for 1 minute. Next, the triboelectric charge was measured by the above-described means, and the obtained charge was defined as the charge N (mC / kg).
The chargeability was evaluated from the obtained absolute value of the charge amount N.

(Evaluation criteria)
A: The absolute value of the charge amount is 70 (mC / kg) or more. (Especially excellent chargeability)
B: The absolute value of the charge amount is 60 (mC / kg) or more and less than 70 (mC / kg). (Excellent chargeability)
C: Absolute value of the charge amount is 50 (mC / kg) or more and less than 60 (mC / kg). (Good chargeability)
D: The absolute value of the charge amount is 40 (mC / kg) or more and less than 50 (mC / kg). (Slightly inferior in chargeability)
E: Absolute value of the charge amount is less than 40 (mC / kg). (Poor in chargeability)

  Further, the two-component developer was left in a high-temperature and high-humidity environment (30 ° C./80%) for 24 hours, and then placed in a 50 cc plastic container and shaken 200 times for 1 minute. The measured charge amount was defined as a charge amount H (mC / kg).

From the obtained charge amount N and charge amount H, charge retention (%) = 100 × charge amount H (mC / kg) / charge amount N (mC / kg)
The charge retention rate (%) in a high temperature environment was calculated, and the environmental stability of the chargeability was evaluated based on the following criteria.

(Evaluation criteria)
A: The charge retention (%) is 70% or more. (Especially excellent environmental stability of chargeability)
B: The charge retention (%) is 60% or more and less than 70%. (Excellent environmental stability for charging)
C: Charge retention (%) is 50% or more and less than 60%. (Good environmental stability of chargeability)
D: Charge retention (%) is 40% or more and less than 50%. (Slightly inferior in environmental stability of chargeability)
E: Charge retention (%) is less than 40%. (Inferior in environmental stability of chargeability)

(Developability)
A commercially available color laser printer (HP Color LaserJet 3525dn, manufactured by HP) was modified to operate even with only one color process cartridge, and evaluated. The toner contained therein was removed from the cyan cartridge mounted on the color laser printer, and the inside was cleaned with an air blow. Then, the toner (200 g) to be evaluated was filled in instead. Under normal temperature and normal humidity (23 ° C., 60% RH), using a Canon office planner (64 g / m ² ) as an image receiving paper, 20,000 sheets of a 1% print rate chart were continuously output as images. After outputting the image, a halftone image was further output, and the presence or absence of image streaks in the developing roller and the halftone image was observed, and the developability was evaluated as follows.

(Evaluation criteria)
A: No vertical streak in the sheet discharge direction, which is regarded as a development streak, is seen on the developing roller and the image of the halftone portion. (Especially excellent in developability)
B: Although there are one to three thin streaks on the developing roller, no vertical streaks in the sheet discharge direction which are regarded as developing streaks are seen on the image of the halftone portion. (Excellent developability)
C: Although there are 4 to 6 fine streaks on the developing roller, vertical streaks in the sheet discharge direction which are regarded as developing streaks are not seen on the image of the halftone portion. (Good developability)
D: Seven to nine fine streaks are present on the developing roller, and visible developing streaks are seen on the image of the halftone portion. (Slightly inferior in developability)
E: Ten or more remarkable development stripes are seen on the development roller and the image of the halftone portion. (Poor in developability)

(Fixing)
A color laser printer (HP Color LaserJet 3525dn, manufactured by HP) from which the fixing unit was removed was prepared, and the toner was taken out of the cyan cartridge and filled with the toner to be evaluated instead. Next, an unfixed toner image (0.9 mg / cm ² ) having a length of 2.0 cm and a width of 15.0 cm was passed on a receiving paper (Canon office planner 64 g / m ² ) using the filled toner. It was formed in a portion 1.0 cm from the upper end in the direction. Next, the removed fixing unit was modified so that the fixing temperature and the process speed could be adjusted, and a fixing test of an unfixed image was performed using the modified unit.

  First, in a normal temperature and normal humidity environment (23 ° C., 60% RH), the process speed is set to 230 mm / s, the initial temperature is set to 130 ° C., and the set temperature is sequentially increased by 5 ° C., and the above-mentioned unfixed state is set at each temperature. The image was fixed.

The evaluation criteria for the low-temperature fixability are as follows. The low-temperature-side fixing start point is defined as when the surface of the image is rubbed five times at a speed of 0.2 m / sec with silbon paper (Daspar K-3) under a load of 4.9 kPa (50 g / cm ² ). , The minimum temperature at which peeling of images having a diameter of 150 μm or more is less than 3 pieces. If the fixation is not performed properly, the image peeling tends to increase.

(Evaluation criteria)
A: Low-temperature-side fixing start point is 125 ° C. or less (low-temperature fixability is particularly excellent)
B: low-temperature side fixing start point is 130 ° C. or 135 ° C. (excellent in low-temperature fixing property)
C: low-temperature-side fixing start point is 140 ° C. or 145 ° C. (good low-temperature fixability)
D: Low-temperature side fixing start point is 150 ° C. or 155 ° C. (slightly inferior in low-temperature fixability)
E: Low-temperature-side fixing start point is 160 ° C. or more (inferior in low-temperature fixing property)
(Manufacturing stability)
The production stability of each toner was evaluated according to the following criteria.

(Evaluation criteria)
A: The weight average particle diameter of the toner is less than 6.5 μm (excellent in production stability)
B: The toner has a weight average particle diameter of 6.5 μm or more and less than 7.0 μm (excellent in production stability).
C: The toner has a weight average particle diameter of 7.0 μm or more and less than 8.0 μm (good production stability)
D: The toner has a weight average particle diameter of 8.0 μm or more and less than 9.0 μm (slightly inferior in production stability).
E: The toner has a weight average particle diameter of 9.0 μm or more (inferior in production stability)
The results are shown in Table 4.

Claims (6)

A method for producing a toner having toner particles,
The production method
Polymerizable monomer, a granulation step in which particles of a composition containing an amorphous polyester resin and crystalline polyester resin to obtain a suspension is formed in an aqueous medium,
Polymerization step of polymerizing the polymerizable monomer contained in the particles of the composition in the suspension, and,
Adjusting the pH of the aqueous medium in the suspension to 6.0 or more and 10.0 or less, and heating the temperature of the aqueous medium to or higher than the glass transition temperature of the amorphous polyester resin;
The includes the step of forming the toner particles through,
The acid value of the non-crystalline polyester resin The method for producing a toner, wherein the higher than the acid value of the crystalline polyester resin. The method according to claim 1, wherein the amorphous polyester resin has an acid value of 1.0 mgKOH / g to 20.0 mgKOH / g. The acid value of the crystalline polyester resin The method for producing a toner according to claim 1 or 2 or less 50.0% relative to the acid value of the amorphous polyester resin. 4. The method according to claim 1, wherein a content of the amorphous polyester resin in the toner is 0.5% by mass or more and 10.0% by mass or less. 5. The pH of the aqueous medium in the step of heating the temperature of the aqueous medium above the glass transition temperature of the amorphous polyester resin 6. The method for producing a toner according to any one of claims 1 to 4, wherein the toner content is 5 or more and 10.0 or less. The time for heating the temperature of the aqueous medium above the glass transition temperature of the amorphous polyester resin is, the toner manufacturing method according to any one of claims 1 to 5 is at least 2 hours.

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