JP6676987B2 - toner - Google Patents

Description

  The present invention relates to a toner for developing an electrostatic latent image.

  Electrostatic image developing toner used for electrophotographic image formation (hereinafter simply referred to as “toner”) includes, for example, a toner for fixing at the time of fixing in order to increase the printing speed and save energy of the image forming apparatus. There is a demand for reducing the thermal energy of such materials. For this reason, there has been a demand for a toner having even better low-temperature fixability. As such a toner, there is known a toner having a crystalline polyester having a sharp melt property as a binder resin, which is designed so that the glass transition point and the melt viscosity of the binder resin are reduced. (For example, see Patent Document 1).

  Further, a technique for realizing both low-temperature fixability and toner storage stability is known. As the technology, for example, in a toner before fixing, the crystalline polyester is present in a crystalline state to satisfy the storage stability of the toner, and in fixing, the amorphous resin is compatible with the crystalline polyester and softens. It is known that the toner can be fixed at a low temperature (for example, see Patent Document 2).

JP 2007-33773 A JP 2014-153638 A

  However, the toner containing the crystalline polyester may be insufficiently adapted to further increase the fixing speed. That is, in the above-mentioned toner, when the fixing speed is further increased, sufficient thermal energy and sufficient time for the crystal structure to change at the time of fixing cannot be ensured, and the effect of improving the fixing property cannot be sufficiently obtained. In some cases, it may not be obtained, or the fixability may be deteriorated.

  In addition, even if the toner has a fixing property required for high-speed fixing, the toner particles in the toner particles may have a large decrease in the temperature of the fixing unit immediately after printing is started and a case in which the temperature of the fixing unit is in an equilibrium state and is stable. The degree of change in the crystal structure of the crystalline component may vary greatly, and in particular, when printing at high speed on paper having a large basis weight, the stability of glossiness may be insufficient.

  Further, if the crystalline polyester is excessively compatible with the binder resin, the discharge temperature is high in a high-speed machine for forming an image at a high speed. For this reason, the stability of the fixed image of the print image becomes insufficient, and a problem such as tacking may occur.

  The present invention has a sufficient low-temperature fixability even in high-speed image formation by an electrophotographic method, has a high glossiness stability even in a paper type having a large basis weight, and has both a toner particle and a fixed image. It is an object to provide a toner having thermal stability.

The present invention relates to a toner for developing an electrostatic latent image containing toner base particles containing at least a binder resin, wherein the binder resin is a toner containing a crystalline polyester, and the following formulas (1) and ( A toner that satisfies both the relations of 2) and (3) is provided.
Formula (1) 0.01 ≦ ΔH1 / ΔHth <0.20
Formula (2) 0.06 ≦ ΔH2 / ΔHth <0.25
Formula (3) 55 <Tm <90

  In the above formula, ΔHth represents the enthalpy of fusion (J / g) calculated by the atomic group contribution method from the weight ratio of the molecular structure derived from the linear aliphatic monomer contained in the toner, and ΔH1 is the differential of the toner. Represents the endothermic amount (J / g) of the endothermic peak of the crystalline polyester in the first heating step in the scanning calorimetry, and ΔH2 is the crystalline polyester in the second heating step in the differential scanning calorimetry of the toner. Represents the endothermic amount (J / g) of the endothermic peak, and Tm represents the melting point (° C.) of the crystalline polyester.

  ADVANTAGE OF THE INVENTION According to the present invention, it has sufficient low-temperature fixability even in high-speed image formation by an electrophotographic method, has high glossiness stability even on a paper type having a large basis weight, and has a high toner particle and fixed image quality. A toner having thermal stability in both can be provided.

FIG. 1 is a diagram schematically illustrating a configuration of an example of an image forming apparatus using a toner according to an embodiment of the present disclosure.

The toner in one embodiment of the present invention is a toner for developing an electrostatic latent image. The toner satisfies any of the following expressions (1), (2), and (3).
Formula (1) 0.01 ≦ ΔH1 / ΔHth <0.20
Formula (2) 0.06 ≦ ΔH2 / ΔHth <0.25
Formula (3) 55 <Tm <90

[ΔHth]
ΔHth represents the enthalpy of fusion (J / g) calculated by the atomic group contribution method from the weight ratio of the molecular structure derived from the linear aliphatic monomer contained in the toner. More specifically, the crystalline polyester contained in the binder resin described below is limited to a structural unit derived from a linear aliphatic monomer (hereinafter, also referred to as “binder resin-containing linear aliphatic monomer”). On the other hand, the value of the enthalpy of fusion calculated from the mass ratio by the atomic group contribution method is defined as ΔHth. The number of moles of the ester group used in the calculation of ΔHth is the smaller number of moles of the total of the carboxylic acid residues and the total of the alcohol residues of the structural units derived from the binder resin-containing linear aliphatic monomer. is there.

  The binder resin-containing linear aliphatic monomer refers to a linear aliphatic polycarboxylic acid, a linear aliphatic polyhydric alcohol, and a linear aliphatic hydroxycarboxylic acid. The binder resin-containing linear aliphatic monomer may be included in a crystalline polyester monomer described below, or may be included in an amorphous resin monomer described below, or may be included in both. Is also good.

  Decrease in crystallinity of the crystalline polyester alone due to the monomer or molecular weight used in combination with the production of the crystalline polyester, decrease in crystallinity due to compatibilization with the activator when the crystalline polyester is made into fine particles by emulsification, dissolution, etc., Due to a change in crystallinity due to compatibilization with another binder resin or wax (release agent) due to heat history at the time of toner formation, etc., ΔH described later measured by DSC in the toner is generally larger than ΔHth. Lower.

  ΔHth, specifically, Properties of Polymers: Their Correlation with Chemical Structure; Their Numerical Estimation and Prediction from Additive Group Contributions (by D.W. van Krevelen and Klaas te Nijenhuis, ISBN: 9780080548197) group contribution as set forth in Calculated using the method parameters.

[ΔH1 and ΔH2]
The above ΔH1 is the endothermic amount (J / g) of the endothermic peak of the crystalline polyester in the first heating process in the differential scanning calorimetry (DSC) of the toner, and the above ΔH2 is the second endothermic DSC in the toner. This is the endothermic amount (J / g) of the endothermic peak of the crystalline polyester during the temperature raising process.

  Using the toner particles as a sample, the mixture is heated from room temperature to 150 ° C. at a heating rate of 10 ° C./min by DSC (first heating process) to determine the relationship between the temperature and the calorific value. The sample is cooled to 0 ° C. at a temperature lowering rate of 1 minute, and heated again to 150 ° C. at a rate of 10 ° C./minute (second temperature raising process) to collect data. Maintain at 0 ° C. and 150 ° C. for 5 minutes each. The amount of heat absorbed by the crystalline polyester in the first heating process can be ΔH1, and the amount of heat absorbed in the second heating process can be ΔH2.

  In the DSC curve obtained by the DSC, the melting peaks related to ΔH1 and ΔH2 overlap with peaks derived from other toner constituent materials such as a release agent described later, and are obtained as overlapping peaks having two or more peak tops. The method of obtaining ΔH1 and ΔH2 in this case will be described below using ΔH1 as an example. ΔH2 is obtained in the same manner as ΔH1.

  First, the endothermic amount ΔH (J / g) from the start point to the end point of the overlapping peak with respect to the baseline is determined, and the partial area of the melting peak derived from the crystalline polyester when the peak area of the overlapping peak is 100%. The rate S1 (%) is obtained, and ΔH1 (J / g) can be calculated by ΔH (J / g) × S1 (%).

  First, the partial area ratio S1 divides the peak plane by a perpendicular line lowered from the minimum point between the plurality of peak tops in the overlapping peak to the temperature axis, and is closest to the melting point of the crystalline polyester alone in the overlapping peak. The peak having the peak top temperature is obtained as a melting peak derived from the crystalline polyester, and its partial area ratio is determined.

  When the DSC curve does not have a local minimum value due to the shape of the overlapping peak being broad, the partial area ratio S1 is determined by the slope of the DSC curve between the peaks, that is, the absolute value of the first derivative. The peak area is obtained by dividing the peak plane by a perpendicular line lowered from the minimum point to the temperature axis and calculating the partial area ratio.

  When the absolute value of the difference between the peak temperatures of the overlapping peaks is 5 ° C. or less, even if the peaks are sharp, the overlapping of the peaks becomes larger, and it is difficult to obtain the partial area ratio. In this case, the amount of heat absorbed in the second heating process when the other material constituting the toner particles, such as the release agent, is measured alone is multiplied by the content in the toner, and is multiplied by the first time. ΔH1 can be calculated by subtracting from the entire heat absorption amount, and ΔH2 can be calculated by subtracting from the entire second heat absorption amount.

  The toner satisfies ΔH1 / ΔHth <0.20. In such a toner, a part of the crystalline polyester contributing to the fixing property is in a state of being compatible with the amorphous resin, and the crystal structure can be easily melted at the time of fixing. As a result, low-temperature fixing can be realized even in a high-speed machine. Further, in the initial stage of continuous printing, the crystalline polyester crystals are reliably dissolved even when the temperature at the time of fixing is lowered. Therefore, a change in glossiness due to a difference in fixing temperature history can be reduced. Further, when the binder resin further contains an amorphous resin, for example, an amorphous polyester, the interface between the crystalline polyester and the amorphous polyester becomes compatible. Therefore, the crushing resistance of the toner can be further improved, and the crushing of the toner particles can be suppressed even in the developing machine of the high-speed machine subjected to strong physical stress.

  The toner satisfies 0.01 ≦ ΔH1 / ΔHth. In such a toner, a part of the molecular chain of the crystalline polyester is crystallized, and the bleed out of the low softening point component is suppressed, and the storage stability of the toner is improved.

  The toner satisfies ΔH2 / ΔHth <0.25. Such a toner can suppress a change in the state of crystallization due to a difference in the history of the fixing temperature in the image after fixing (such as a change in the temperature due to the operating condition). Further, a change in glossiness can be reduced by a combination with the condition of ΔH1 / ΔHth <0.20.

  The toner satisfies 0.06 ≦ ΔH2 / ΔHth. In such a toner, since the crystalline polyester exists in a crystallized state, the thermal stability of the fixed image is improved even in a high-speed machine having a high sheet discharge temperature. Therefore, tacking can be suppressed.

  The toner satisfies the above expression (3). The Tm is the melting point (° C.) of the crystalline polyester. In such a toner described above, even when the temperature inside the toner or the temperature near the interface between the toner particles and the paper does not rise sufficiently during fixing by a high-speed machine, low-temperature fixability can be ensured, and the low-temperature fixability can be ensured. It is possible to achieve both high-temperature storage stability.

  As described above, the toner satisfying the above expressions (1) to (3) has a flexible structure capable of lowering the fixing temperature. Therefore, even in a toner containing a crystalline polyester composed of a linear aliphatic monomer having a relatively low melting point, the heat of fusion derived from the crystalline polyester is designed to be at an appropriate level both before and after heating and melting. In addition, the energy required for melting the crystals is kept low, and low-temperature fixing is achieved by compatibilization with the amorphous resin. Furthermore, stability such as tacking resistance of printed images and gloss stability during continuous printing are achieved. To be satisfied.

The toner preferably further satisfies the following formula (4), and more preferably satisfies the following formula (5).
Formula (4) 0.10 ≦ ΔH2 / ΔHth ≦ 0.20
Formula (5): 0.12 ≦ ΔH2 / ΔHth ≦ 0.16

  By making ΔH2 / ΔHth smaller, the crystalline polyester can be more sufficiently melted even in a high-speed machine having a short fixing time in an image after fixing. As a result, the influence of the fixing temperature on the crystalline state of the crystalline polyester can be further reduced. ΔH2 / ΔHth is preferably 0.10 or more, and more preferably 0.12 or more, from the viewpoint of suppressing a decrease in storage stability of an image.

It is preferable that the toner further satisfies the following expression (6).
Equation (6) 0.05 ≦ ΔH1 / ΔHth ≦ 0.15

  ΔH1 / ΔHth ≧ 0.05 indicates that a sufficient amount of crystalline substance exists in a crystalline state. Therefore, it is preferable from the viewpoint of more surely suppressing a decrease in heat resistance. ΔH1 / ΔHth ≦ 0.15 is preferable from the viewpoint of melting the crystal structure more quickly during fixing.

  The ΔH1 is preferably 2 J / g or more and less than 10 J / g, and the ΔH1 is more preferably 3 J / g or more and less than 7 J / g. From the viewpoint of more reliably dissolving the crystalline polyester at the time of fixing, ΔH1 is preferably less than 10 J / g, and more preferably ΔH1 is less than 7 J / g. Further, from the viewpoint of further improving the thermal stability during storage of the toner, ΔH1 is preferably 2 J / g or more, more preferably 3 J / g or more.

It is preferable that ΔHth is 25 J / g or more from the viewpoint of low-temperature fixability. The Tm preferably satisfies the following expression (7) from the viewpoint of suppressing tacking at the time of fixing and exhibiting sufficient low-temperature fixing properties even in a high-speed machine.
Formula (7): 65 <Tm <80

  The toner contains toner base particles containing at least a binder resin. The binder resin contains a crystalline polyester.

[Crystalline polyester]
The crystalline polyester has not a stepwise endothermic change but a distinct endothermic peak in the differential scanning calorimetry (DSC) of the toner. Specifically, a clear endothermic peak means that the half-width of the endothermic peak is within 15 ° C. when measured at a heating rate of 10 ° C./min in differential scanning calorimetry (DSC) described in Examples. It means a peak. The crystalline polyester may be one kind or more.

  The content of the crystalline polyester in the binder resin is preferably 2 to 30% by mass, and more preferably 10 to 20% by mass. If it is less than 2% by mass, both the plasticizing effect and the low-temperature fixability may be insufficient. If the amount is 30% by mass or more, the thermal stability as a toner and the stability against physical stress may be insufficient. When the content is in the more preferable range, it is easy to control the melting enthalpy to a preferable range by appropriately selecting the configuration and the production method of the amorphous resin described later.

  The melting point Tm of the crystalline polyester is preferably 55 to 90 ° C. from the viewpoint of achieving both fixing property and thermal stability. Further, the glass transition temperature Tg of the crystalline polyester is determined from the viewpoints of improving the fluidity when melted in the toner and the fixability due to the plasticizing effect when compatibilized, and the partially compatible crystalline polyester during storage of the toner. From the viewpoint of suppressing a decrease in thermal stability due to the above, the temperature is preferably from -50C to 20C, more preferably from -30C to 15C, and even more preferably from -20C to 10C. preferable.

  The weight average molecular weight Mw of the crystalline polyester is preferably 5,000 to 50,000, more preferably 10,000 to 35,000, and more preferably 13,000 to 25,000, from the viewpoint of appropriate control of crystallinity and low-temperature fixability by plasticization. Is more preferable. Further, the number average molecular weight Mn of the crystalline polyester is preferably from 1500 to 15000, and more preferably from 2500 to 10000, from the viewpoint of suppressing migration of the crystalline polyester and achieving low-temperature fixability by compatibilization during fixing. More preferably, it is more preferably 3,000 to 6,000. Further, the molecular weight distribution Mw / Mn of the crystalline polyester is preferably from 2.0 to 20, more preferably from 3.0 to 10, from the viewpoint of improving sharp meltability and low-temperature fixability. More preferably, it is 3.5 to 7.0.

  Further, the acid value of the crystalline polyester is from 3 to 3 from the viewpoint of stability of emulsification at the time of preparing an aqueous dispersion of the crystalline polyester resin, and from the viewpoint of facilitating obtaining the preferred molecular weight and molecular weight distribution described above. It is preferably 50, more preferably 8 to 30, and still more preferably 15 to 25.

  The Tm, Tg, Mw, Mn, and acid value of the crystalline polyester can be appropriately adjusted depending on the type of the monomer of the crystalline polyester, polymerization conditions, and the like.

The crystalline polyester has a structure of a polycondensation product of a divalent or higher carboxylic acid (polyhydric carboxylic acid) and a divalent or higher valent alcohol (polyhydric alcohol). The polyhydric carboxylic acid and the polyhydric alcohol may be either one kind or more. The crystalline polyester is formed from a polycarboxylic acid component and a polyhydric alcohol. It is preferable that the polyvalent carboxylic acid constituting the crystalline polyester has a carbon number C (acid) of 6 or more, and the polyhydric alcohol has a carbon number C (alcohol) of 2 or more and satisfies the following relationship.
C (acid) -C (alcohol) ≧ 3

  When two or more polyvalent carboxylic acids are present, C (acid) is the carbon number of the polyvalent carboxylic acid having the largest content. In the case of the same amount, the carbon number of the polyvalent carboxylic acid having the largest carbon number is used. Similarly, when two or more polyhydric alcohols are present, C (alcohol) is the carbon number of the polyhydric alcohol having the highest content. In the case of the same amount, the carbon number of the polyvalent carboxylic acid having the largest carbon number is used.

  An increase in C (acid) and C (alcohol) increases the interaction between crystalline polyesters between different molecules, and thus the crystalline polyester is appropriately incompatible with the amorphous resin. Is preferred. Further, satisfying the above formula is preferable from the viewpoint that the crystallinity of the crystalline polyester can be controlled to an appropriate range since the regularity of the molecular chain of the crystalline polyester is weakened.

  By using a polycarboxylic acid and a polyhydric alcohol satisfying the above, it becomes easy to adjust ΔH1, ΔH2, and Tm that satisfy the above-described formulas (1) to (3). The upper limits of C (acid) and C (alcohol) are not particularly limited, but it is preferable that C (acid) is 20 or less and that C (alcohol) is 20 or less.

  From the viewpoint of maintaining the crystallinity of the crystalline polyester in the toner, the content of the structural unit derived from the linear aliphatic monomer among the monomer-derived structural units in the crystalline polyester is preferably 50% by mass or more. Preferably, it is 80% by mass or more from the above viewpoint. When the crystalline polyester contains a structural unit derived from an aromatic monomer, the melting point of the crystalline polyester is generally high, and when the crystalline polyester contains a structural unit derived from a branched aliphatic monomer, the crystallinity of the crystalline polyester is increased. Generally lower. In many cases, it is preferable to use a linear aliphatic monomer.

  The valences of the polycarboxylic acid and the polyhydric alcohol are each preferably 2 to 3, and particularly preferably 2 respectively. Therefore, a case where the valence is 2 (that is, dicarboxylic acid or diol) will be described as a particularly preferred embodiment.

  The dicarboxylic acid is preferably an aliphatic dicarboxylic acid, and an aromatic dicarboxylic acid may be used in combination. As described above, the aliphatic dicarboxylic acid is preferably a linear type from the viewpoint of improving the crystallinity.

  Examples of the aliphatic dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, and 1,10-decane Dicarboxylic acid, 1,11-undecane dicarboxylic acid, 1,12-dodecane dicarboxylic acid (dodecane diacid), 1,13-tridecane dicarboxylic acid, 1,14-tetradecane dicarboxylic acid, 1,16-hexadecane dicarboxylic acid, , 18-octadecanedicarboxylic acids, their lower alkyl esters, and their acid anhydrides.

  Among the aliphatic dicarboxylic acids, the polyvalent carboxylic acid is preferably an aliphatic dicarboxylic acid having 6 to 12 carbon atoms because the above-described effects are easily obtained.

  Examples of the aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, t-butyl isophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4'-biphenyldicarboxylic acid. Among them, terephthalic acid, isophthalic acid or t-butyl isophthalic acid is preferred from the viewpoint of availability and emulsification.

  From the viewpoint of ensuring sufficient crystallinity of the crystalline polyester unit, the content of the aliphatic dicarboxylic acid in the dicarboxylic acid is preferably 50 mol% or more, more preferably 70 mol% or more, It is more preferably at least 80 mol%, particularly preferably at least 100 mol%.

  The diol is preferably an aliphatic diol, and may further contain a diol other than the aliphatic diol, if necessary. It is preferable that the aliphatic diol is a linear type from the viewpoint of improving the crystallinity.

  Examples of the aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8 -Octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18 -Octadecanediol and 1,20-eicosanediol.

  Among the aliphatic diols, an aliphatic diol having 2 to 12 carbon atoms is preferable, and an aliphatic diol having 3 to 10 carbon atoms is more preferable, from the viewpoint of easily obtaining the above-described effects.

  Examples of the diol other than the aliphatic diol include a diol having a double bond and a diol having a sulfonic acid group. Specifically, examples of the diol having a double bond include 2-butene-1,4-diol, 3-butene-1,6-diol and 4-butene-1,8-diol.

  The content of the aliphatic diol in the diol is preferably 50 mol% or more, more preferably 70 mol%, from the viewpoint of securing the crystallinity and the compatibility between low-temperature fixability and gloss stability. It is at least 80% by mole, more preferably at least 80% by mole, particularly preferably at least 100% by mole.

  The ratio of the diol to the dicarboxylic acid may be adjusted from the viewpoint of more easily adjusting the formulas ΔH1, ΔH2 and Tm satisfying the above-mentioned formulas (1) to (3) from the hydroxyl of the diol to the carboxyl group [COOH] of the dicarboxylic acid. The equivalent ratio [OH] / [COOH] with the group [OH] is preferably 2.0 / 1.0 to 1.0 / 2.0, and 1.5 / 1.0 to 1.0 / 2.0. It is more preferably 1.5, and particularly preferably 1.3 / 1.0 to 1.0 / 1.3.

  The crystalline polyester can be synthesized by polycondensing (esterifying) the polycarboxylic acid and the polyhydric alcohol using a known esterification catalyst. The above catalyst may be one kind or more.

  Examples of the catalyst include alkali metal compounds such as sodium and lithium; compounds containing Group 2 elements such as magnesium and calcium; metal compounds such as aluminum, zinc, manganese, antimony, titanium, tin, zirconium, and germanium; A phosphoric acid compound; a phosphoric acid compound; and an amine compound.

  Examples of tin metal compounds include dibutyltin oxide, tin octylate, tin dioctylate, and salts thereof. Examples of metal compounds of titanium include titanium alkoxides such as tetranormal butyl titanate, tetraisopropyl titanate, tetramethyl titanate, and tetrastearyl titanate; titanium acylates such as polyhydroxytitanium stearate; titanium tetraacetylacetonate, titanium lactate; Titanium chelates, such as titanium triethanol aminate; Examples of the metal compound of germanium include germanium dioxide. Examples of metal compounds of aluminum include oxides such as polyaluminum hydroxide, aluminum alkoxides and tributyl aluminate.

  The polymerization temperature in the polycondensation is not limited, but is preferably 150 to 250 ° C., and the polymerization time in the polycondensation is not limited, but is preferably 0.5 to 10 hours. During the polymerization, the pressure inside the reaction system may be reduced if necessary.

[Amorphous resin]
The binder resin preferably further contains an amorphous resin. An amorphous resin is a resin that does not have the above-mentioned crystallinity, that is, does not show a clear endothermic peak in DSC under the above-mentioned conditions. The amorphous resin may be one kind or more. Examples of the amorphous resin include vinyl resins such as styrene resin, acrylic resin, and styrene-acryl resin; and amorphous polyester. Among them, from the viewpoint of low-temperature fixability, a styrene-acrylic resin and an amorphous polyester resin are preferable, and an amorphous polyester resin is particularly preferable.

  Examples of the polymerizable monomer for forming the vinyl-based resin include a monomer having an ethylenically unsaturated bond capable of performing radical polymerization, specifically, a styrene-based monomer and (Meth) acrylate monomers are included.

  Examples of the styrene monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, and p-methylstyrene. n-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4 -Dimethylstyrene, 3,4-dichlorostyrene and derivatives thereof.

  Examples of the (meth) acrylate monomer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, Included are butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate.

  The polymerizable monomer for forming the vinyl-based resin may further include a third vinyl-based monomer. Examples of the third vinyl monomer include acid monomers such as maleic anhydride and vinyl acetic acid, and acrylamide, methacrylamide, acrylonitrile, ethylene, propylene, butylene vinyl chloride, N-vinylpyrrolidone and butadiene. It is.

  The polymerizable monomer may further include a polyfunctional vinyl monomer. Examples of polyfunctional vinyl monomers include tertiary or higher alcohols such as ethylene glycol, propylene glycol, butylene glycol, and hexylene glycol, dimethacrylates such as diacrylate, divinylbenzene, pentaerythritol, and trimethylolpropane; Methacrylate.

  The copolymerization ratio of the polyfunctional vinyl monomer to the entire polymerizable monomer is usually 0.001 to 5% by mass, preferably 0.003 to 2% by mass, more preferably 0.01 to 5% by mass. 1% by mass. The content of the gel component insoluble in tetrahydrofuran with respect to the entire polymerizable monomer, which is accompanied by the use of the polyfunctional vinyl monomer, is usually 40% by mass or less, preferably 20% by mass or less.

  The amorphous polyester is a polyester having no crystallinity, and can be synthesized in the same manner as the crystalline polyester described above except that it does not have the crystallinity.

  Examples of polycarboxylic acids for forming the amorphous polyester include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonane Dicarboxylic 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 Acids, aliphatic saturated dicarboxylic acids such as 1,18-octadecanedicarboxylic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid; maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid , Isododecenyl succinic acid, n-dodecenyl succinic acid, n-octenyl succinic acid Unsaturated aliphatic dicarboxylic acids such as citric acid; divalent or higher carboxylic acids such as trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid and pyrenetetracarboxylic acid; anhydrides thereof Or acid chlorides.

  Examples of polyhydric alcohols for forming amorphous polyesters include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, Aliphatic diols such as 14-tetradecanediol, 1,18-octadecanediol, and 1,20-eicosanediol; bisphenols such as bisphenol A and bisphenol F, and bisphenols such as ethylene oxide adduct and propylene oxide adduct thereof Alkylene oxide adducts; glyce Include; down, pentaerythritol, hexamethylol melamine, hexa ethylene melamine, tetramethylol benzoguanamine, trihydric or higher polyols, such as tetra-ethyl benzoguanamine.

  The amorphous resin has a structure derived from a linear aliphatic polycarboxylic acid, a linear aliphatic polyhydric alcohol, and a linear aliphatic hydroxycarboxylic acid, that is, forms the amorphous resin. Having a structure of a linear aliphatic polycarboxylic acid, a linear aliphatic polyhydric alcohol, and a compound formed by intramolecular dehydration condensation of a linear aliphatic hydroxycarboxylic acid or a hydroxycarboxylic acid. Including one or more selected from the group consisting of derivatives, while improving the fixability by introducing a flexible structure into the amorphous resin, and at the same time, the thermal properties as a toner even in a state where the crystalline polyester has low crystallinity It is preferable because excellent stability can be maintained.

  The linear aliphatic polycarboxylic acid, the linear aliphatic polyhydric alcohol, and the structure derived from the linear aliphatic hydroxycarboxylic acid may be contained in the side chain of the amorphous resin, It may be contained in a chain. Examples of the amorphous resin having the above structure include an amorphous resin having the above structure introduced into the side chain of a vinyl resin, and the above structure in the main chain or side chain of the amorphous polyester resin, or both. Is introduced.

  Examples of the method of introducing the above structure into the side chain of the vinyl resin include a vinyl resin having a functional group such as a hydroxyl group, a carboxyl group, an amino group and an ester group in the side chain by a polymerization reaction. It is formed by intramolecular dehydration condensation of a functional group and a precursor of the above structure, i.e., the aforementioned linear aliphatic polycarboxylic acid, linear aliphatic polyhydric alcohol, and linear aliphatic hydroxycarboxylic acid or hydroxycarboxylic acid. A method of reacting at least one selected from the group consisting of lactone derivatives having a compound structure by a known method such as a condensation reaction or transesterification.

  Alternatively, an amorphous resin having the above structure in the side chain of the vinyl-based resin may be a straight-chain aliphatic polycarboxylic acid, a straight-chain aliphatic polyhydric alcohol, and a straight-chain aliphatic hydroxycarboxylic acid in the side chain. It can also be obtained by a method of copolymerizing a vinyl monomer having a structure derived from it with other monomers constituting the amorphous resin. This method is preferable from the viewpoint of reactivity and from the viewpoint of suppressing a cross-linking reaction due to a covalent bond of a polymer chain.

  Amorphous resin having the above structure introduced into the main chain or side chain of the amorphous polyester resin, or both, for example, linear aliphatic polycarboxylic acid, linear aliphatic polyhydric alcohol, And a monomer for forming an amorphous polyester resin containing at least one selected from the group consisting of lactone derivatives having a structure of a linear aliphatic hydroxycarboxylic acid or a compound formed by intramolecular dehydration condensation of hydroxycarboxylic acid. It is obtained by a method of copolymerization. The introduction position of the structure of the linear aliphatic polycarboxylic acid, the linear aliphatic polyhydric alcohol, and the linear aliphatic hydroxycarboxylic acid or the hydroxycarboxylic acid in the amorphous resin may be a trivalent or higher hydroxyl group. It can be controlled by a known method such as a method of controlling the amount and timing of charging of one or both of the monomer having the carboxylic acid group and the monomer having a trivalent or higher carboxyl group.

  Examples of the linear aliphatic polycarboxylic acid include aliphatic saturated dicarboxylic acids, and examples thereof include glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, and 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-hexadecane Includes dicarboxylic acids and 1,18-octadecanedicarboxylic acid.

  Examples of the linear aliphatic polyhydric alcohol include an aliphatic diol, and examples thereof include 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-pentanediol. Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tride Includes candiol, 1,14-tetradecanediol, 1,18-octadecanediol and 1,20-eicosanediol.

  Examples of the straight-chain aliphatic hydroxycarboxylic acids include 3-hydroxypropionic acid, 4-hydroxybutyric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid, 7-hydroxyheptanoic acid, and 12-hydroxydodecanoic acid. It is.

  Examples of the lactone derivative of the linear aliphatic hydroxycarboxylic acid include β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, 8-hydroxyoctanoic lactone, 12-hydroxydodecanoic lactone, 13 Lactone-hydroxytridecanoate, lactone 14-hydroxytetradecanoate and lactone 15-hydroxypentadecanoate.

  The content of the structural unit derived from the linear aliphatic polycarboxylic acid, the linear aliphatic polyhydric alcohol or the linear aliphatic hydroxycarboxylic acid in the amorphous resin is 0.5% from the above viewpoint. It is preferable that it is 15 mass%, it is more preferable that it is 1-10 mass%, and it is more preferable that it is 2-5 mass%.

  It is preferable that the amorphous resin is an amorphous polyester having a linear aliphatic structure because the introduction position of the linear aliphatic structure in the amorphous resin can be easily controlled. The linear aliphatic structure may be contained in any of the main chain and the side chains of the amorphous polyester, but the fact that it is contained in the main chain is due to the introduction of a flexible structure into the main chain. The effect on the low-temperature fixability is increased, and the effect of plasticization by melting of the crystalline polyester is more likely to act on the main chain structure of the amorphous resin, thereby increasing the change in the viscoelasticity of the toner. It is preferable from the point that it becomes possible. Examples of the straight-chain aliphatic structure include a straight-chain aliphatic polycarboxylic acid, a straight-chain aliphatic polyhydric alcohol, and a straight-chain aliphatic hydroxycarboxylic acid. From the above viewpoint, the content of the linear aliphatic structure in the amorphous polyester is preferably 0.5 to 15% by mass, more preferably 1 to 8% by mass, and 1.5 to 15% by mass. More preferably, it is 5% by mass.

  The amorphous resin preferably has a number average molecular weight (Mn) of 1500 to 25000, and a weight average molecular weight (Mw) of 10,000 to 80000. It is preferable that the molecular weight of the amorphous resin be in the above range from the viewpoint of achieving both a sufficient low-temperature fixing property and excellent high-temperature storage property. The molecular weight of the amorphous resin is measured by gel permeation chromatography (GPC) described below.

  The glass transition point of the amorphous resin is preferably from 35 to 70C, more preferably from 50 to 60C. It is preferable that the glass transition point of the amorphous resin is 35 ° C. or higher from the viewpoints of sufficient thermal strength and sufficient high-temperature storage stability in the toner. Further, it is preferable that the glass transition point of the amorphous resin is 70 ° C. or lower from the viewpoint of sufficient low-temperature fixability.

  The glass transition point of the amorphous resin was obtained by obtaining a DSC curve using a non-crystalline resin as a measurement sample in DSC, analyzing the data in the second heating process, and measuring the data before the rise of the first endothermic peak. By drawing an extension of the base line and a tangent showing the maximum slope from the rising portion of the first peak to the peak apex, the temperature is determined as the temperature at the intersection of the extension and the tangent.

  The acid value of the amorphous resin is selected from the viewpoints of emulsification stability at the time of preparing an aqueous dispersion of the amorphous polyester resin, the viewpoint of facilitating obtaining the preferable molecular weight and the molecular weight distribution, and the production of toner. An appropriate amount of a crosslinked structure is formed between the divalent or higher valent ion sometimes added and the carboxy group of the amorphous polyester, so that the thermal stability and fixability at low temperature and the separability by maintaining elasticity at high temperature. It is preferable that it is 3-50, and it is more preferable that it is 8-30 from a viewpoint that improvement of can be expected.

  The content of the amorphous resin in the binder resin is preferably from 70 to 95% by mass, and more preferably from 80 to 90% by mass. When the content of the amorphous resin is within the above range, the viewpoint of compatibility between the low-temperature fixing property and the high-temperature offset resistance, the viewpoint of uniform dispersion of the colorant described below in the toner base particles, and the favorable image density From the viewpoint of ensuring uniformity of image density.

  The amorphous resin can be synthesized by a known method. For example, the vinyl resin is preferably produced by an emulsion polymerization method.

  The emulsion polymerization method is a method in which a polymerizable monomer such as styrene or acrylate is dispersed in an aqueous medium and polymerized. In order to disperse the polymerizable monomer in the aqueous medium, a surfactant is preferably used, and a polymerization initiator and a chain transfer agent can be used for the polymerization.

  The polymerization initiator is not limited, and examples thereof include hydrogen peroxide, acetyl peroxide, cumyl peroxide, tert-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, and dichloroperoxide. Benzoyl, bromomethylbenzoyl peroxide, lauroyl peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyl peroxycarbonate, tetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, pertriphenylacetic acid tert-hydroperoxide, tert-butyl formate, tert-butyl peracetate, tert-butyl perbenzoate, tert-butyl perphenylacetate, tert-butyl permethoxyacetate, per-N- (3-toluyl ) Palmitic acid-tert-butyl And the like; 2,2′-azobis (2-aminodipropane) hydrochloride, 2,2′-azobis- (2-aminodipropane) nitrate, 1,1′-azobis (1-methyl) Azo compounds such as butyronitrile-3-sulfonate), 4,4′-azobis-4-cyanovaleric acid, and poly (tetraethylene glycol-2,2′-azobisisobutyrate).

  The amount of the polymerization initiator to be added varies depending on the desired molecular weight and molecular weight distribution of the amorphous resin, but specifically, it is preferably in the range of 0.1 to 5% by mass based on the polymerizable monomer. .

  The chain transfer agent is preferable from the viewpoint of controlling the molecular weight of the polymer. The chain transfer agent is not limited and examples include alkyl mercaptans and mercapto fatty acid esters. The amount of the chain transfer agent to be added varies depending on the desired molecular weight and molecular weight distribution of the amorphous resin, but is specifically preferably in the range of 0.1 to 5% by mass based on the polymerizable monomer. .

  The surfactant is preferable from the viewpoint of preventing aggregation of droplets dispersed in the aqueous medium. Examples of the surfactant include a cationic surfactant, an anionic surfactant, and a nonionic surfactant. In addition, the said surfactant can be used for the same purpose also in dispersion liquids, such as a coloring agent and a release agent.

  Examples of the cationic surfactant include dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide and hexadecyl trimethyl ammonium bromide.

  Examples of the nonionic surfactant include dodecyl polyoxyethylene ether, hexadecyl polyoxyethylene ether, norylphenyl polyoxoethylene ether, lauryl polyoxyethylene ether, sorbitan monooleate polyoxyethylene ether, and styrylphenyl poly. Oxyethylene ether and monodecanoyl sucrose are included.

  Examples of the anionic surfactant include aliphatic soaps such as sodium stearate and sodium laurate, sodium lauryl sulfate, sodium dodecylbenzenesulfonate and sodium polyoxyethylene (2) lauryl ether sulfate.

[Hybrid crystalline polyester (hybrid resin)]
The crystalline polyester may include a hybrid crystalline polyester (also simply referred to as “hybrid resin”). The hybrid crystalline polyester is a resin in which a crystalline polyester unit and an amorphous resin unit are chemically bonded.

  The crystalline polyester unit is a portion derived from the crystalline polyester in the hybrid resin, and has a molecular chain having the same chemical structure as that of the crystalline polyester. This crystalline polyester is the same as the crystalline polyester described above. Further, the amorphous resin unit is a portion derived from the amorphous resin in the hybrid resin, and has a molecular chain having the same chemical structure as that of the amorphous resin. This amorphous resin is the same as the above-mentioned amorphous resin. The amorphous resin in the amorphous resin unit is preferably other than polyester. The inclusion of the above units in the hybrid resin (in the toner base particles or the toner particles) means that the chemical structure is specified using a known instrumental analysis method such as NMR or methylation P-GC / MS. Can be confirmed by

  The hybrid resin may be in any form such as a block copolymer or a graft copolymer, but is preferably a graft copolymer. The graft copolymer is preferable from the viewpoint that the thermal stability of the toner can be increased by suppressing the crystalline polyester having an excessively low molecular weight from being detached from the toner base particles.

  Further, from the above viewpoint, the crystalline polyester unit is preferably grafted using an amorphous resin unit other than the crystalline polyester as a main chain. That is, the hybrid crystalline polyester is preferably a graft copolymer having a main chain of an amorphous resin unit and side chains of a crystalline polyester unit. Such a graft copolymer is preferable in that even a side chain of a crystalline polyester having insufficient crystallinity can interact with a crystallized polyester crystallized by a plurality of side chains. As a result, the elimination of low-molecular-weight components was suppressed, and at the same time, even domains of crystalline polyester having a small domain diameter were stabilized and partially compatibilized near the domain interface. A large amount of polyester can be present. As a result, it is easy to obtain a hybrid resin having ΔH1 and ΔH2 satisfying the above formula (1).

  Note that the hybrid resin may further have a functional group such as a sulfonic acid group, a carboxyl group, and a urethane group. The functional group may be in a crystalline polyester unit or in an amorphous resin unit.

  In addition, the above-mentioned hybrid resin is preferably a resin in which a crystalline polyester unit and an amorphous resin unit are bonded without interposing a nitrogen atom from the viewpoint of preventing ΔH1 / ΔHth from being too high.

  The Mw of the hybrid resin is preferably from 5,000 to 100,000, more preferably from 7000 to 50,000, more preferably from 8,000 to 50,000, from the viewpoint of ensuring both sufficient low-temperature fixability and excellent long-term storage stability. It is particularly preferably 20,000. It is preferable that the hybrid resin has an Mw of 100,000 or less from the viewpoint of sufficient low-temperature fixability. When the Mw of the hybrid resin is 5000 or more, the viewpoint of suppressing the excessive progress of the compatibility between the hybrid resin and the amorphous resin during the storage of the toner, and reducing the image defect due to fusion between the toners. It is preferable from the viewpoint of suppressing it effectively.

  The content of the crystalline polyester unit in the hybrid resin is preferably more than 75% by mass and 97% by mass or less. Further, the content is more preferably more than 78% by mass and 95% by mass or less, further preferably more than 85% by mass and 92% by mass or less. The above content range is preferable from the viewpoint of imparting sufficient crystallinity to the hybrid resin.

  Further, the crystalline polyester unit preferably further includes a structural unit derived from a compound for chemically bonding with the amorphous resin unit, in addition to the structural unit derived from the polyvalent carboxylic acid and the polyhydric alcohol. . The compound is preferably capable of polycondensation with respect to the polycarboxylic acid and the polyhydric alcohol, and has an unsaturated bond (preferably a double bond).

  Examples of the compound include polycarboxylic acids having a double bond such as methylene succinic acid, fumaric acid, maleic acid, 3-hexenedioic acid, and 3-octenedioic acid; 2-butene-1,4- Polyhydric alcohols having a double bond such as diol, 3-butene-1,6-diol and 4-butene-1,8 diol; The content of the structural unit derived from the above compound in the crystalline polyester unit is preferably 0.5 to 20% by mass.

  The amorphous resin unit increases the affinity between the amorphous resin and the hybrid resin when the binder resin contains the amorphous resin, and from the viewpoint of facilitating the incorporation of the hybrid resin into the amorphous resin. It is preferable from the viewpoint of improving charging uniformity.

  The amorphous resin unit is made of the same kind of resin as the amorphous resin contained in the binder resin, from the viewpoint of the improvement of the affinity and the improvement of the charging uniformity. It is more preferable from the viewpoint of easy control of the value of ΔH2.

  Here, “the same type of resin” means that a characteristic chemical bond is commonly contained in the repeating unit. Here, the “characteristic chemical bond” is described in the National Institute for Materials Science (NIMS) substance / material database (http://polymer.nims.go.jp/PoLyInfo/guide/jp/term_polymer.html). "Polymer classification". That is, polyacryl, polyamide, polyanhydride, polycarbonate, polydiene, polyester, polyhaloolefin, polyimide, polyimine, polyketone, polyolefin, polyether, polyphenylene, polyphosphazene, polysiloxane, polystyrene, polysulfide, polysulfone, polyurethane, polyurea , Polyvinyl and other polymers are referred to as “characteristic chemical bonds”.

  Further, `` the same type of resin '' in the case where the resin is a copolymer, in the chemical structure of a plurality of monomer types constituting the copolymer, when the monomer type having the chemical bond is a structural unit, a characteristic Resins having common chemical bonds. Therefore, even when the properties of the resin itself are different from each other, or even when the molar component ratios of the monomer species constituting the copolymer are different from each other, the same type of the same type has a characteristic chemical bond in common. It can be regarded as a resin.

  For example, a resin (or resin unit) formed by styrene, butyl acrylate and acrylic acid and a resin (or resin unit) formed by styrene, butyl acrylate and methacrylic acid form at least a chemical bond constituting polyacryl. Have. Therefore, they are the same type of resin. To further illustrate, a resin (or resin unit) formed by styrene, butyl acrylate and acrylic acid and a resin (or resin unit) formed by styrene, butyl acrylate, acrylic acid, terephthalic acid and fumaric acid mutually As a common chemical bond, it has at least a chemical bond constituting polyacryl. Therefore, they are the same type of resin.

  Examples of the amorphous resin unit include a vinyl resin unit, a urethane resin unit, and a urea resin unit. Among them, a vinyl resin unit is preferable from the viewpoint of easily controlling thermoplasticity. The vinyl resin unit only needs to have a polymer structure of a vinyl compound, and examples thereof include an acrylate resin unit, a styrene-acrylate resin unit, and an ethylene-vinyl acetate resin unit. Above all, a styrene-acrylate resin unit (styrene-acryl resin unit) is preferred from the viewpoint of plasticity during heat fixing.

  Further, the amorphous resin unit is preferably obtained by addition-polymerizing a compound for chemically bonding to the crystalline polyester unit in addition to the styrene monomer and the (meth) acrylate monomer. . Specifically, it is preferable to use a compound which is included in the crystalline polyester unit and has an ester bond with a hydroxyl group (—OH) derived from a polyhydric alcohol or a carboxyl group (—COOH) derived from a polycarboxylic acid. For example, in the above compound, the amorphous resin unit is preferably capable of addition polymerization with respect to the styrene monomer and the (meth) acrylate monomer, and preferably has a carboxyl group or a hydroxyl group.

  Examples of the above compounds include compounds having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, monoalkyl maleate and monoalkyl itaconate; 2-hydroxyethyl ( (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene Compounds having a hydroxyl group, such as glycol mono (meth) acrylate; The content of the structural unit derived from the compound in the amorphous resin unit is preferably 0.5 to 20% by mass.

  The content of the amorphous resin unit is preferably 3% by mass or more and less than 25% by mass with respect to the total amount of the hybrid resin. Further, the content is more preferably 5% by mass or more and less than 22% by mass, and further preferably 8% by mass or more and less than 15% by mass. It is preferable that the content is in the above range from the viewpoint of imparting sufficient crystallinity to the hybrid resin and from the viewpoint of easily obtaining a binder resin for satisfying the relationship of the above formula (1).

  Note that ΔH1 and ΔH2 are the content ratio of the crystalline polyester (unit) and the amorphous resin (unit) in the binder resin, the chemical structure of the crystalline polyester (unit) and the amorphous resin (unit), and the like. Depends on. It is particularly preferred that the content of the amorphous resin unit in the hybrid resin be within the above range from the viewpoint of easily obtaining a binder resin satisfying the above formula (1).

  The hybrid resin can be manufactured by, for example, first to third manufacturing methods described below.

  The first production method is a method of producing a hybrid resin by performing a polymerization reaction for synthesizing a crystalline polyester unit in the presence of a previously synthesized amorphous resin unit.

  In this method, first, a monomer (preferably, a vinyl monomer such as a styrene monomer or a (meth) acrylate monomer) constituting the above-described amorphous resin unit is subjected to an addition reaction to form an amorphous resin unit. A crystalline resin unit is synthesized. Next, in the presence of the amorphous resin unit, a polyvalent carboxylic acid and a polyhydric alcohol are polymerized to synthesize a crystalline polyester unit. At this time, a polyhydric carboxylic acid and a polyhydric alcohol are subjected to a condensation reaction and a polyhydric carboxylic acid or a polyhydric alcohol is added to the amorphous resin unit to synthesize a hybrid resin.

  In the above-mentioned first production method, it is preferable to incorporate a site where these units can react with each other in the crystalline polyester unit or the amorphous resin unit. Specifically, at the time of synthesizing the amorphous resin unit, the above-mentioned compound is used in addition to the monomers constituting the amorphous resin unit. When the compound reacts with a carboxy group or a hydroxy group in the crystalline polyester unit, the crystalline polyester unit chemically and quantitatively binds to the amorphous resin unit. When the crystalline polyester unit is synthesized, the above-mentioned compound having an unsaturated bond may be further contained in the monomer.

  According to the first production method, a hybrid resin having a structure (graft structure) in which a crystalline polyester unit is molecularly bonded to an amorphous resin unit can be synthesized.

  The second production method is a method of producing a hybrid resin by forming a crystalline polyester unit and an amorphous resin unit, respectively, and combining them.

  In this method, first, a polyvalent carboxylic acid and a polyhydric alcohol are subjected to a condensation reaction to synthesize a crystalline polyester unit. In addition to the reaction system for synthesizing the crystalline polyester unit, the above-mentioned monomer constituting the amorphous resin unit is subjected to addition polymerization to synthesize the amorphous resin unit. At this time, it is preferable to incorporate a site where the crystalline polyester unit and the amorphous resin unit can react with each other in one or both of the crystalline polyester unit and the amorphous resin unit as described above.

  Next, by reacting the synthesized crystalline polyester unit and the amorphous resin unit, a hybrid resin having a structure in which the crystalline polyester unit and the amorphous resin unit are molecularly bonded can be synthesized.

  Further, when the reactive site is not incorporated into any of the crystalline polyester unit and the amorphous resin unit, the crystalline polyester unit and the amorphous resin unit in a coexisting system, the crystalline polyester unit Alternatively, a method may be employed in which a compound having a site capable of binding to both the amorphous resin unit and the amorphous resin unit is introduced. Thereby, a hybrid resin having a structure in which the crystalline polyester unit and the amorphous resin unit are molecularly bonded via the compound can be synthesized.

  The third production method is a method of producing a hybrid resin by performing a polymerization reaction for synthesizing an amorphous resin unit in the presence of a crystalline polyester unit.

  In this method, first, a polyvalent carboxylic acid and a polyhydric alcohol are subjected to a condensation reaction to carry out polymerization to synthesize a crystalline polyester unit. Next, in the presence of the crystalline polyester unit, a monomer constituting the amorphous resin unit is subjected to a polymerization reaction to synthesize an amorphous resin unit. At this time, similarly to the above-mentioned first production method, it is preferable to incorporate a site where these units can react with each other in the crystalline polyester unit or the amorphous resin unit.

  According to the third manufacturing method, a hybrid resin having a structure (graft structure) in which an amorphous resin unit is molecularly bonded to a crystalline polyester unit can be synthesized.

  Among the first to third production methods, the first production method can easily synthesize a hybrid resin having a structure in which a crystalline polyester resin chain is grafted to an amorphous resin chain, and can simplify the production process. Therefore, it is preferable. In the first manufacturing method, since the amorphous polyester unit is formed beforehand and the crystalline polyester unit is bonded, the orientation of the crystalline polyester unit tends to be uniform. Therefore, it is preferable from the viewpoint of surely synthesizing a hybrid resin suitable for each color toner.

[Measuring method of Mw and Mn]
Mw and Mn of the resin are determined by the following method. Using an apparatus “HLC-8120GPC” (manufactured by Tosoh Corporation) and a column “TSKguardcolumn + TSKgelSuperHZ-M3” (manufactured by Tosoh Corporation), tetrahydrofuran (THF) was used as a carrier solvent at a flow rate of 0.2 mL / while maintaining the column temperature at 40 ° C. And the measurement sample (amorphous resin (A)) is dissolved in THF so as to have a concentration of 1 mg / mL under a dissolution condition in which the sample is treated with an ultrasonic disperser at room temperature for 5 minutes. A sample solution was obtained by treating with a 0.2 μm membrane filter, and 10 μL of the sample solution was injected into the apparatus together with the above-mentioned carrier solvent, and detected using a refractive index detector (RI detector). The molecular weight distribution of the measurement sample is calculated using a calibration curve measured using 10 monodisperse polystyrene standard particles.

[Method for measuring Tg]
The glass transition point of the resin is measured by a method (DSC method) specified in ASTM (American Society for Testing and Materials) D3418-82. That is, 4.5 mg of a measurement sample (amorphous resin) is precisely weighed to two decimal places, sealed in an aluminum pan, and set in a sample holder of a differential scanning calorimeter “DSC8500” (manufactured by PerkinElmer). . The reference uses an empty aluminum pan and performs temperature control of temperature rise-fall-temperature rise at a measurement temperature of −10 to 120 ° C., a temperature rise rate of 10 ° C./min, and a temperature decrease rate of 10 ° C./min, An analysis is performed based on the data at the second heating. The value of the intersection of the extension line of the baseline before the rise of the first endothermic peak and the tangent line indicating the maximum slope from the rising portion of the first endothermic peak to the peak apex is defined as the glass transition temperature.

[Method of measuring acid value]
The acid value represents the mass of potassium hydroxide (KOH) required for neutralizing the acid contained in 1 g of a sample in mg. The acid value of the resin is measured by the following procedure according to JIS K0070-1992.

(Preparation of reagents)
Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add ion-exchanged water to make 100 mL, and prepare a phenolphthalein solution. 7 g of JIS special grade potassium hydroxide is dissolved in 5 mL of ion-exchanged water, and ethyl alcohol (95% by volume) is added to make 1 liter. After leaving the container in an alkali-resistant container for 3 days so as not to be exposed to carbon dioxide, the mixture is filtered to prepare a potassium hydroxide solution. Orientation follows the description of JIS K0070-1992.

(Main test)
2.0 g of the pulverized sample is precisely weighed in a 200 mL Erlenmeyer flask, and 100 mL of a mixed solution of toluene / ethanol (toluene: ethanol at a volume ratio of 2: 1) is added and dissolved for 5 hours. Next, several drops of a phenolphthalein solution prepared as an indicator are added, and titration is performed using the prepared potassium hydroxide solution. The end point of the titration is the time when the light red color of the indicator continues for about 30 seconds.

(Blank test)
Except that no sample is used (that is, only a mixed solution of toluene / ethanol (toluene: ethanol at a volume ratio of 2: 1) is used), the same operation as in the above-mentioned test is performed.

The acid value is calculated by substituting the titration results of this test and blank test into the following equation (1).
Equation (1) A = [(B−C) × f × 5.6] / S
A: Acid value (mgKOH / g)
B: Amount of potassium hydroxide solution added during blank test (mL)
C: Addition amount of potassium hydroxide solution at the time of this test (mL)
f: Factor of 0.1 mol / L potassium hydroxide ethanol solution S: Mass of sample (g)

[Method of measuring Tm]
The melting point (Tm) of the crystalline polyester resin is the peak temperature of the endothermic peak and can be measured by DSC using diamond DSC (manufactured by PerkinElmer).

  Specifically, a sample was prepared using an aluminum pan KITNO. B0143013, set in a sample holder of a thermal analyzer Diamond DSC (manufactured by PerkinElmer), and change the temperature in the order of heating, cooling and heating. During the first heating, the temperature is raised from room temperature (25 ° C.) to 0 ° C. during the second heating, to 150 ° C. at a heating rate of 10 ° C./min, and kept at 150 ° C. for 5 minutes. The temperature is decreased from 150 ° C. to 0 ° C. at a temperature decreasing rate of 0 ° C./min, and the temperature of 0 ° C. is maintained for 5 minutes. The temperature at the peak top of the endothermic peak in the endothermic curve obtained at the time of the second heating is measured as the melting point.

  The toner base particles may further contain components other than the binder resin as long as the effects according to the present embodiment can be obtained. Examples of such other components include colorants, release agents, and charge control agents. The above-mentioned other components may be one kind or more independently.

  As the colorant, various known colorants such as carbon black, black iron oxide, dyes, and pigments can be used.

  Examples of the carbon black include channel black, furnace black, acetylene black, thermal black, and lamp black. Examples of the above black iron oxide include magnetite, hematite, and titanium iron trioxide.

  Examples of the dye include C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, and 95.

  Examples of the pigment include C.I. I. Pigment Red 5, 48: 1, 48: 3, 53: 1, 57: 1, 81: 4, 122, 139, 144, 149, 150, 166, 177, 178, 222, 238, 269, C.I. I. Pigment Orange 31, 43 and C.I. I. Pigment Yellow 14, 17, 17, 74, 93, 94, 138, 155, 156, 158, 180, 185, C.I. I. Pigment Green 7, C.I. I. Pigment Blue 15: 3 and 60.

  The content of the colorant in the toner base particles is preferably 1 to 10% by mass, and more preferably 2 to 8% by mass.

  Various known waxes can be used as the release agent. Examples of the wax include polyolefin waxes such as low molecular weight polypropylene, polyethylene, oxidized polypropylene and polyethylene; and ester waxes such as behenate behenate. Specifically, polyolefin waxes such as polyethylene wax and polypropylene wax; branched hydrocarbon waxes such as microcrystalline wax; long-chain hydrocarbon waxes such as paraffin wax and sasol wax; dialkyl ketones such as distearyl ketone System wax: carnauba wax, montan wax, behenate behenate, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecanediol distea Ester waxes, such as ethylene glycol, tristearyl trimellitate, and distearyl maleate; alcohols such as ethylenediamine behenylamide and trimellitate tristearylamide Such as de-based wax is included.

  It is preferred that the release agent has no interaction with the crystalline polyester. The interaction is, for example, compatibility.

  The release agent preferably has a low melting point, specifically, a melting point of 60 to 100 ° C., from the viewpoint of releasability during low-temperature fixing. Further, the release agent preferably has a melting point of about (Tm−10) ° C. to (Tm + 20) ° C. with respect to the melting point Tm of the crystalline polyester.

  The content of the release agent in the toner base particles is preferably from 1 to 20% by mass, and more preferably from 5 to 20% by mass. It is preferable that the content ratio of the release agent in the toner particles is in the above range from the viewpoint of compatibility between the separating property and the fixing property.

  As a method of introducing the release agent into the toner particles, in the aggregation and fusing steps of the toner production method described below, fine particles consisting of the release agent alone are mixed with the amorphous resin fine particles, the crystalline polyester fine particles, and the like in an aqueous medium. For agglomeration and fusion. The release agent fine particles can be obtained as a dispersion in which the release agent is dispersed in an aqueous medium. The dispersion liquid of the release agent fine particles is prepared by heating an aqueous medium containing a surfactant to a temperature higher than the melting point of the release agent, adding the molten release agent solution, and applying mechanical energy such as mechanical stirring or ultrasonic waves. After finely dispersing by applying energy or the like, it can be prepared by cooling.

  When the amorphous resin is, for example, a styrene acrylic resin, a release agent is previously compounded with the amorphous resin fine particles (styrene acrylic resin fine particles) to be subjected to the aggregation and fusion steps. Alternatively, the release agent can be introduced into the toner particles. Specifically, a release agent is dissolved in a solution of a polymerizable monomer for forming a styrene acrylic resin, and the obtained solution is added to an aqueous medium containing a surfactant, and the same as above. After finely dispersing the above solution by applying mechanical energy such as mechanical stirring or ultrasonic energy, and then polymerizing at a desired polymerization temperature by adding a polymerization initiator, a so-called miniemulsion polymerization method, a release agent Can be prepared.

  As the charge control agent, various compounds known as charge control agents can be used. The content of the charge control agent in the toner particles is preferably from 0.1 to 10% by mass, more preferably from 1 to 5% by mass.

  The toner base particles preferably have a core-shell structure including core particles containing a binder resin and a colorant and a resin shell layer covering the surface thereof. In the shell layer, the surface of the core particle may be completely covered with the shell layer, or a part of the surface may be exposed. It is preferable that the toner base particles have a core-shell structure from the viewpoint of high-temperature storability. The resin constituting the shell layer is not limited, but is preferably an amorphous polyester or a vinyl resin.

  The toner may have an external additive attached to the surface thereof in addition to the toner base particles. The external additive is externally added to the toner base particles in order to improve the fluidity, chargeability, cleaning property, and the like of the toner. Examples of the external additive include a fluidizing agent and a cleaning aid. One or more external additives may be used. The toner base particles (toner particles) to which the external additive has adhered can form a one-component developer.

  The content of the external additive in the toner particles is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass with respect to 100 parts by mass of the toner particles.

  Examples of the external additive include particles of an inorganic compound such as silica, titania, alumina, and strontium titanate; organic fine particles of a homopolymer such as styrene and methyl methacrylate and a copolymer thereof; and a metal salt of a higher fatty acid A lubricant such as particles of The external additive may be subjected to a hydrophobic treatment with a known surface treatment agent such as a silane coupling agent or silicone oil as needed.

  The volume average particle diameter (volume-based median diameter) of the toner particles is preferably 3 to 8 μm, and more preferably 5 to 8 μm. The volume average particle diameter is controlled by, for example, the concentration of a coagulant to be used or the amount of an organic solvent added, the fusing time, the composition of the polymer, etc. it can. It is preferable that the volume average particle diameter is in the above range from the viewpoints of improving transfer efficiency, improving halftone image quality, and improving image quality of fine lines and dots.

  The volume average particle size of the toner particles is measured and calculated by using a measuring device in which a computer system equipped with data processing software “Software V3.51” is connected to “Multisizer 3” (manufactured by Beckman Coulter). You. Specifically, 0.02 g of a measurement sample (toner particles) was added to 20 mL of a surfactant solution (for the purpose of dispersing toner particles, for example, a surfactant was prepared by diluting a neutral detergent containing a surfactant component 10 times with pure water. The mixture is then added to the toner solution, and then subjected to ultrasonic dispersion for 1 minute to prepare a toner dispersion. This toner dispersion is pipetted into a beaker containing “ISOTON II” (manufactured by Beckman Coulter, Inc.) in a sample stand until the indicated concentration of the measuring device becomes 8%. Here, by setting the concentration within this range, a reproducible measured value can be obtained. Then, in the measurement device, the measurement particle count number is set to 25,000, the aperture diameter is set to 100 μm, and the frequency value obtained by dividing the measurement range of 2 to 60 μm into 256 is calculated. % Particle size is determined as the above volume average particle size.

  The average circularity of the toner particles is preferably from 0.930 to 1.000, and more preferably from 0.950 to 0.995, from the viewpoint of stability of charging characteristics and low-temperature fixability. It is preferable that the average circularity is in the above range from the viewpoints of improving the crushing resistance of the toner particles, thereby suppressing the contamination of the frictional charging member, stabilizing the chargeability of the toner, and improving the image quality.

The average circularity is measured using “FPIA-2100” (manufactured by Sysmex Corporation). Specifically, the sample (toner particles) was soaked in an aqueous solution containing a surfactant, subjected to ultrasonic dispersion treatment for 1 minute to disperse the sample, and then subjected to measurement conditions using “FPIA-2100” (manufactured by Sysmex Corporation). In the HPF (high-magnification imaging) mode, photographing is performed at an appropriate density of 3,000 to 10,000 HPFs detected, and the circularity of each toner particle is calculated according to the following formula, and the circularity of each toner particle is calculated. It is calculated by adding and dividing by the total number of toner particles. In the following formula, L0 represents the peripheral length of the particle projected image, and L1 represents the peripheral length of a circle having the same projected area as the particle image.
Formula: circularity = L1 / L0

The softening point of the toner particles is preferably from 80 to 120 ° C, more preferably from 90 to 110 ° C, from the viewpoint of low-temperature fixability. The softening point is measured by a flow tester shown below. Specifically, first, in an environment of 20 ° C. and 50% RH, 1.1 g of a sample (toner particles) is placed in a petri dish, flattened and left for 12 hours or more, and then a molding machine “SSP-10A” ( (Shimadzu Corporation) with a pressure of 3820 kg / cm ² (3.75 MPa) for 30 seconds to produce a cylindrical molded sample having a diameter of 1 cm. Next, the molded sample was heated at a load of 196 N (20 kgf), a starting temperature of 60 ° C. and a preheating time of 300 seconds by a flow tester “CFT-500D” (manufactured by Shimadzu Corporation) in an environment of 24 ° C. and 50% RH. At a heating rate of 6 ° C./min, it is extruded from the end of preheating using a 1 cm diameter piston through a hole (1 mm diameter × 1 mm) of a cylindrical die, and an offset value of 5 mm is set by a melting temperature measuring method of a heating method. The offset method temperature Toffset measured in the above is defined as the softening point.

  Each of the above color toners may further contain carrier particles. Each of the color toners having carrier particles in addition to the toner particles constitutes a two-component developer.

  The carrier particles include magnetic particles. Examples of the magnetic material in the magnetic particles include conventionally known materials such as metals such as iron, ferrite, and magnetite; alloys of these metals with metals such as aluminum and lead. Among them, the magnetic particles are preferably ferrite particles.

  The carrier particles may be resin-coated carrier particles having the above-described magnetic particles and a resin layer covering the surface, or magnetic-particle-dispersed carrier particles in which fine particles of the above-described magnetic material are dispersed in resin particles. It may be. Examples of the resin for coating in the resin-coated carrier particles include olefin resin, cyclohexyl methacrylate-methyl methacrylate copolymer, styrene resin, styrene-acryl resin, silicone resin, ester resin, and fluororesin. Examples of the resin for constituting the resin particles of the magnetic material-dispersed carrier particles include an acrylic resin, a styrene-acrylic resin, a polyester resin, a fluororesin, and a phenol resin.

  The size of the carrier particles is preferably in the range of 15 to 100 μm in terms of volume average particle size, more preferably in the range of 25 to 60 μm. The content of the carrier particles in each color toner is, for example, such that the toner particle concentration becomes 3 to 9% by mass. The volume average particle size of the carrier particles can be measured by, for example, a laser diffraction particle size distribution analyzer HELOS (manufactured by SYMPATEC) equipped with a wet disperser.

  Each of the above color toners can be manufactured by a known method. For example, the first step of mixing each of the above color toners in an aqueous medium by mixing an amorphous resin fine particle dispersion containing amorphous resin fine particles as a binder resin and a colorant fine particle dispersion containing colorant fine particles. A second step of adding a coagulant to the mixture prepared in the first step, a third step of raising the temperature of the mixture prepared in the second step, and a crystalline resin A fourth step of adding a crystalline resin fine particle dispersion liquid containing fine particles, and a fifth step of aggregating and fusing amorphous resin fine particles, crystalline resin fine particles and colorant fine particles to form aggregated particles, Including.

  The amorphous resin fine particles and the crystalline resin fine particles can be adjusted by a known method such as an emulsion polymerization method, a miniemulsion polymerization method, a phase inversion emulsification method, or a combination thereof. In addition, the amorphous resin fine particles may contain an internal additive such as a release agent. In this case, it is more preferable to use a mini-emulsion polymerization method.

  When an internal additive such as a release agent is contained in the toner particles, the internal additive may be added to the amorphous resin fine particles as described above, or a separately prepared dispersion liquid of the internal additive fine particles. May be added in the first step, or after the addition of the coagulant in the second step and before the addition of the crystalline resin fine particle dispersion in the fourth step.

  The above manufacturing method may further include, after the fifth step, a shelling step for forming a shell layer on the aggregated particles generated in the fifth step. By the manufacturing method including the shelling step, toner particles having a core-shell structure can be manufactured. Specifically, first, the above aggregated particles are used as core particles, and amorphous resin fine particles for forming a shell layer are added to a dispersion of the core particles, and the amorphous resin for forming a shell layer is formed on the surface of the core particles. The fine particles are further aggregated and fused to form a shell layer covering the surface of the core particles.

  In the first step, an amorphous resin particle dispersion containing amorphous resin particles and a colorant particle dispersion containing colorant particles are mixed in an aqueous medium. In the case where a release agent is contained in the toner particles and the amorphous resin fine particles do not contain a release agent, it is preferable to further mix a release agent fine particle dispersion in the first step. .

  An amorphous resin fine particle dispersion, a colorant fine particle dispersion, and a release agent fine particle dispersion are prepared as follows.

  The amorphous resin fine particle dispersion is prepared, for example, by synthesizing an amorphous resin constituting toner particles, and dispersing the amorphous resin into fine particles in an aqueous medium. Examples of the method of dispersing an amorphous resin in an aqueous medium include forming amorphous resin fine particles from a monomer for obtaining an amorphous resin, and preparing an aqueous dispersion of the amorphous resin fine particles. (I), and an amorphous resin is dissolved or dispersed in an organic solvent (solvent) to prepare an oil phase liquid, and the oil phase liquid is dispersed in an aqueous medium by phase inversion emulsification or the like. A method (II) of removing an organic solvent (solvent) after forming an oil droplet in a controlled state to a desired particle size is included.

  The aqueous medium refers to a liquid containing at least 50% by mass of water, and the aqueous medium is, for example, preferably only water. Examples of components other than water include organic solvents that dissolve in water, and examples include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, dimethylformamide, methylcellosolve and tetrahydrofuran. Among these, the organic solvent is preferably an organic solvent that does not dissolve the resin, such as methanol, ethanol, isopropanol, and butanol.

  In the method (I), first, a monomer for obtaining an amorphous resin is added to an aqueous medium together with a polymerization initiator and polymerized to obtain basic particles. Next, preferably, a radical polymerizable monomer and a polymerization initiator for obtaining an amorphous resin are added to the dispersion in which the basic particles are dispersed, and a radical polymerizable monomer is added to the basic particles. The body is seed polymerized.

  As the above-mentioned polymerization initiator, a water-soluble polymerization initiator can be used. Suitable examples of the water-soluble polymerization initiator include a water-soluble radical polymerization initiator such as potassium persulfate and ammonium persulfate.

  In the seed polymerization reaction system for obtaining the amorphous resin fine particles, a general chain transfer agent can be used for the purpose of adjusting the molecular weight of the amorphous resin. The chain transfer agent may be one or more, and examples thereof include mercaptans such as octyl mercaptan, dodecyl mercaptan, t-dodecyl mercaptan; n-octyl-3-mercaptopropionate, stearyl-3-mercaptopropionate. Mercaptopropionic acid; and styrene dimer.

  In the method (II), the organic solvent (solvent) used for preparing the oil phase liquid has a low boiling point and low solubility in water from the viewpoint of facilitating the removal treatment after the formation of the oil droplets. Those which are preferred include methyl acetate, ethyl acetate, methyl ethyl ketone, isopropyl alcohol, methyl isobutyl ketone, toluene and xylene. The solvent may be one kind or more.

  The amount of the solvent used (when two or more types are used, the total amount used) is usually in the range of 10 to 500 parts by mass, preferably 100 to 450 parts by mass, per 100 parts by mass of the amorphous resin. Within the range, more preferably within the range of 200 to 400 parts by mass. From the viewpoint of emulsifying and dispersing the oil phase liquid to a desired particle size in the aqueous medium, the amount of the aqueous medium is preferably in the range of 50 to 2,000 parts by mass with respect to 100 parts by mass of the oil phase liquid. , 100 to 1000 parts by mass.

  In the aqueous medium, a dispersion stabilizer may be dissolved, and for the purpose of improving the dispersion stability of oil droplets, a surfactant or resin fine particles may be added. Known dispersion stabilizers can be used, and the dispersion stabilizer is preferably soluble in an acid or alkali such as, for example, tricalcium phosphate, or from an environmental point of view, Preferably, it can be degraded by an enzyme.

  Examples of the surfactant include known anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants. Examples of the resin fine particles include polymethyl methacrylate resin fine particles, polystyrene resin fine particles, and polystyrene-acrylonitrile resin fine particles.

  The emulsification and dispersion of the oil phase liquid can be performed using mechanical energy. Examples of dispersers for emulsifying and dispersing include homogenizers, low-speed shear dispersers, high-speed shear dispersers, friction dispersers, high-pressure jet dispersers, ultrasonic dispersers, and high-pressure impact dispersers. Ultimateizer, included.

  The removal of the organic solvent after the formation of the oil droplets is performed, for example, by gradually increasing the temperature while stirring the entire dispersion liquid in which the amorphous resin fine particles are dispersed in the aqueous medium, and strongly stirring in a certain temperature range. You can do it later. Alternatively, the organic solvent can be removed while reducing the pressure using a reduced-pressure concentrator such as an evaporator.

  The particle diameter of the amorphous resin fine particles (oil droplets) in the amorphous resin fine particle dispersion prepared by the above method (I) or (II) is 60 to 60 in terms of volume-based median diameter (volume average particle diameter). It is preferably in the range of 1000 nm, more preferably in the range of 80 to 500 nm. The volume average particle diameter can be measured by a known method, and can be controlled by the magnitude of mechanical energy at the time of emulsification and dispersion.

  The content of the amorphous resin fine particles in the amorphous resin fine particle dispersion is in the range of 5 to 50% by mass from the viewpoint of suppressing the spread of the particle size distribution of the generated amorphous resin fine particles and improving the toner characteristics. It is preferably within the range, more preferably within the range of 10 to 30% by mass.

  The colorant fine particle dispersion is prepared by dispersing the colorant in the form of fine particles in an aqueous medium. The aqueous medium may be the same as that in the preparation of the above-mentioned amorphous resin fine particle dispersion, and in this aqueous medium, for the purpose of improving the dispersion stability of the colorant, the surfactant or the resin fine particles described above. Etc. may be added. The dispersion of the colorant can be performed in the same manner as in the preparation of the above-mentioned amorphous resin fine particle dispersion.

  From the viewpoint of color reproducibility, the content of the colorant in the colorant fine particle dispersion is preferably in the range of 5 to 50% by mass, and more preferably in the range of 10 to 40% by mass.

  The release agent fine particle dispersion can be prepared in the same manner as the preparation of the colorant fine particles, except that the release agent is used instead of the colorant. The content of the release agent in the release agent fine particle dispersion is in the range of 10 to 50% by mass from the viewpoint of suppressing the occurrence of hot offset and enhancing the separability of the recording medium during fixing. Is preferably, and more preferably in the range of 15 to 40% by mass.

  In the second step, a coagulant is added to the mixture prepared in the first step.

  As the coagulant, a coagulant of a metal salt is preferably used. The coagulant may be one kind or more, and examples thereof include salts of monovalent metals such as salts of alkali metals such as sodium, potassium and lithium; divalent metals such as calcium, magnesium, manganese and copper. And salts of trivalent metals such as iron and aluminum. More specifically, it includes sodium chloride, potassium chloride, lithium chloride, calcium chloride, magnesium chloride, zinc chloride, copper sulfate, magnesium sulfate and manganese sulfate. Among these, salts of divalent or higher valent metals are particularly preferred from the viewpoint that aggregation can be promoted with a small amount.

  In the third step, the temperature of the mixture prepared in the second step is raised.

  The rate of temperature rise of the mixed solution in the third step is preferably 0.8 ° C./min or more. The upper limit of the heating rate is not particularly limited, but is preferably 15 ° C./min or less from the viewpoint of suppressing generation of coarse particles due to rapid fusion. In the third step, the mixture is heated until the temperature of the mixture reaches, for example, the aggregation temperature. The aggregation temperature is preferably equal to or higher than the glass transition temperature of the amorphous resin, and more preferably within a temperature range of −10 to + 10 ° C. with respect to the melting point of the crystalline resin. In the third step, the amorphous resin fine particles and the colorant fine particles aggregate with the increase in temperature to form an aggregate.

  In the case where the release agent is contained in the toner base particles and the amorphous resin fine particles do not contain the release agent, after the coagulant is added in the second step, It is preferable to add the above-mentioned release agent fine particle dispersion before adding the crystalline resin fine particle dispersion.

  In the fourth step, a crystalline resin fine particle dispersion containing at least one kind of crystalline resin fine particles is added to the mixed liquid by the completion of the temperature increase in the third step.

  From the viewpoint of improving low-temperature fixability, color characteristics, chargeability, and high-temperature preservability, the volume average particle size (volume-based median) of the aggregate when the crystalline resin fine particle dispersion is added to the mixture in the fourth step (Diameter) is preferably in the range of 0.2 to 2.5 μm. When the crystalline resin fine particles are added to the mixed solution when the particle size of the aggregate is 2.5 μm or less, the crystalline resin fine particles aggregate on the outside of the aggregate whose particle size has increased to some extent due to the progress of aggregation. This is preferable from the viewpoint of suppressing charging and improving the chargeability and the high-temperature storage property. Further, when the particle diameter of the aggregate is 0.2 μm or more, by adding the crystalline resin fine particles to the mixture, the crystalline resin fine particles do not inhibit the aggregation of the amorphous resin fine particles and the colorant fine particles. From the viewpoint of enhancing the chargeability. The volume-based median diameter of the aggregate can be obtained by measuring the volume average particle diameter with UPA-150 (manufactured by Microtrac Bell Inc.).

  In addition, the temperature of the mixed liquid when adding the crystalline resin fine particle dispersion to the mixed liquid in the fourth step is preferably in the range of -40 to + 10 ° C with respect to the melting point of the crystalline resin fine particles. , -20 to + 5 ° C. Further, in the fourth step, the temperature of the mixed liquid when the crystalline resin fine particle dispersion is added to the mixed liquid may be equal to or higher than the glass transition temperature of the amorphous resin and equal to or lower than the melting point of the crystalline resin. preferable.

  The crystalline resin fine particle dispersion is prepared by synthesizing a crystalline resin and dispersing the crystalline resin in the form of fine particles in an aqueous medium. The crystalline resin fine particle dispersion is, for example, a method of performing a dispersion treatment in an aqueous medium without using a solvent, or dissolving the crystalline resin in a solvent such as methyl ethyl ketone to form a solution, and using a disperser to obtain the solution. Can be prepared by emulsifying and dispersing the compound in an aqueous medium mechanically or by phase inversion emulsification, and then subjecting it to a solvent removal treatment.

  Crystalline resins may contain carboxy groups. In such a case, a basic compound such as ammonia or sodium hydroxide may be added to the aqueous medium in order to ion-dissociate the carboxy group and stably and smoothly emulsify the aqueous phase. In the aqueous medium, a dispersion stabilizer may be dissolved in the same manner as in the preparation of the amorphous resin fine particle dispersion, and in order to improve the dispersion stability of the oil droplets, a surfactant or resin fine particles may be used. May be added. The dispersion treatment of the crystalline resin fine particles can be performed in the same manner as the preparation of the amorphous resin fine particle dispersion.

  The particle size of the crystalline resin fine particles (oil droplets) in the crystalline resin fine particles is preferably 50 to 1000 nm, more preferably 50 to 500 nm, as a volume-based median diameter (volume average particle size). And more preferably within the range of 80 to 500 nm. The volume average particle size can be controlled by the magnitude of mechanical energy during emulsification and dispersion. Further, the content of the crystalline resin fine particles in the crystalline resin fine particle dispersion is from 10 to 50 mass% with respect to 100 mass% of the dispersion from the viewpoint of suppressing the spread of the particle size distribution of the aggregate and improving the toner characteristics. %, More preferably 15 to 40% by mass.

  In the fifth step, the amorphous resin fine particles, the crystalline resin fine particles, and the colorant fine particles are aggregated and fused to form aggregated particles.

  Specifically, when the temperature rise of the mixed liquid of the crystalline resin fine particle dispersion, the amorphous resin fine particle dispersion, and the colorant fine particle dispersion in the third step is completed, stirring is performed while maintaining the temperature of the mixed liquid. Decrease speed. In the fifth step, the aggregation speed of the particles can be advanced by reducing the stirring speed of the mixed liquid to suppress the re-dispersion of the aggregate due to the collision between the aggregates.

  The temperature of the mixed solution in the fifth step is preferably higher than the melting point of the crystalline resin. By lowering the stirring speed while maintaining the temperature of the mixture, the aggregation and fusion of the crystalline resin fine particles, the amorphous resin fine particles, and the colorant fine particles are advanced, and the particle size of the aggregated particles reaches a desired value. Upon reaching, aggregation is stopped by adding a salt such as an aqueous solution of sodium chloride as an aggregation stopping agent to the mixed solution. The particle diameter of the aggregated particles at this time is preferably in the range of 4.5 to 7.0 μm in terms of volume-based median diameter. The volume-based median diameter of the agglomerated particles can be obtained by measuring the volume average particle size using “Coulter Multisizer 3” (manufactured by Beckman Coulter, Inc.).

  In the fifth step, after the aggregation of the particles is stopped by adding one or both of an aggregating terminator and increasing the stirring speed, the temperature is maintained or adjusted while stirring the mixture, and the mixing is performed. It is preferred that melting and fusing of the toner base particles proceed until the average circularity of the particles in the liquid reaches a desired value. At this time, the average circularity of the toner base particles in the mixed liquid is preferably in the range of 0.920 to 1.000, and more preferably in the range of 0.940 to 0.995. The average circularity can be measured by the method described above.

  By the above-described method, effects of particle growth (aggregation of crystalline resin fine particles, amorphous resin fine particles and colorant particles, and release agent fine particles if necessary) and fusion (loss of interface between particles) are effective. And toner particles having more excellent durability can be obtained.

  The method for producing each color toner may further include other steps than the first to fifth steps as long as the effects of the present embodiment can be obtained. Examples of the other steps include a shelling step, a cooling step, a filtration, a washing, a drying step, an external additive treatment step, and a carrier particle mixing step.

  When a toner resin having a core-shell structure is obtained, it is preferable to further perform a shelling step. In the shelling step, an aqueous dispersion of a shell layer forming resin (preferably the amorphous resin) constituting the shell layer is further added to the dispersion containing the aggregated particles generated in the fifth step, and The resin for forming the shell layer is aggregated and fused to the surface of the aggregated particles (core particles). As a result, toner particles having a core-shell structure are obtained.

  At this time, it is preferable to further heat-treat the reaction system until coagulation and fusion of the shell layer forming resin to the surface of the core particle are further strengthened and the particle shape becomes a desired shape. This heat treatment may be performed until the average circularity of the toner particles having the core-shell structure falls within the range of the average circularity.

  In the cooling step, the dispersion of the toner particles is cooled. The cooling rate in the cooling treatment is not limited, but is preferably in the range of 0.2 to 20 ° C./min. The cooling method is not limited, and may be, for example, a method of introducing a refrigerant to the outside of the reaction vessel to cool the dispersion together with the reaction vessel, or a method of cooling by directly supplying cold water to the reaction system. Alternatively, a method in which a reaction system dispersion is charged into cold water may be used.

  In the filtration step, toner base particles are filtered from the dispersion. Examples of the filtration method include a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, and a filtration method using a filter press.

  In the above-mentioned washing step, extraneous substances such as a surfactant and an aggregating agent are removed from the toner base particles (cake-like aggregate) that have been filtered out by washing. The washing process is, for example, a water washing process, and is performed until the electric conductivity of the filtrate falls within a range of, for example, 5 to 10 μS / cm.

  In the drying step, a drying process is performed on the washed toner base particles. Examples of the dryer used in the drying step include known dryers such as a spray dryer, a vacuum freeze dryer, and a reduced pressure dryer, and additionally include a stationary shelf dryer, a movable shelf dryer, and a fluidized shelf dryer. Also included are layer dryers, tumble dryers and stirred dryers. The amount of water contained in the dried toner base particles is preferably 5% by mass or less, more preferably 2% by mass or less.

  Further, in the case where the mother particles of the dried toner particles are agglomerated by weak attraction between particles, a crushing process may be further performed. Examples of the crushing processing device include a mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill, and a food processor.

  In the external additive treatment step, an external additive is added to the dried toner base particles as necessary, mixed, and adhered to the surface of the toner base particles. The addition of the external additive improves the fluidity and chargeability of the toner, and also improves the cleaning properties. The resulting toner particles can be used as a one-component developer.

  In the above carrier particle mixing step, the carrier particles are mixed with the obtained toner particles in such an amount that the concentration of the toner particles becomes 3 to 9% by mass. The obtained mixed powder can be used as a two-component developer.

  The toner is applied to a normal electrophotographic image forming method, and is used for developing an electrostatic latent image. The toner is accommodated in, for example, the image forming apparatus shown in FIG. 1 and is used for forming a toner image on a recording medium.

  The image forming apparatus 100 illustrated in FIG. 1 includes an image reading unit 110, an image processing unit 30, an image forming unit 40, a sheet conveying unit 50, and a fixing device 60.

  The image forming unit 40 includes image forming units 41Y, 41M, 41C, and 41K that form images using toners of Y (yellow), M (magenta), C (cyan), and K (black). Since these have the same configuration except for the contained toner, the symbols representing the colors may be omitted hereafter. The image forming unit 40 further has an intermediate transfer unit 42 and a secondary transfer unit 43. These correspond to a transfer device.

  The image forming unit 41 includes an exposure device 411, a developing device 412, a photosensitive drum 413, a charging device 414, and a drum cleaning device 415. The photoconductor drum 413 is, for example, a negatively charged organic photoconductor. The surface of the photoconductor drum 413 has photoconductivity. The photoconductor drum 413 corresponds to a photoconductor.

  The charging device 414 is, for example, a corona charger. The charging device 414 may be a contact charging device that charges a contact charging member such as a charging roller, a charging brush, or a charging blade by bringing the charging member into contact with the photosensitive drum 413.

  The exposure device 411 includes, for example, a semiconductor laser as a light source, and a light deflecting device (polygon motor) for irradiating the photosensitive drum 413 with laser light corresponding to an image to be formed.

  The developing device 412 is a two-component developing type developing device. The developing device 412 includes, for example, a developing container that stores a two-component developer, a developing roller (magnetic roller) rotatably disposed at an opening of the developing container, and a developing container that allows the two-component developer to communicate with the developing container. A partition wall for partitioning the inside, a transport roller for transporting the two-component developer on the opening side of the developing container toward the developing roller, and a stirring roller for stirring the two-component developer in the developing container. . The developing container contains the toner as a two-component developer.

  The intermediate transfer unit 42 includes an intermediate transfer belt 421, a primary transfer roller 422 that presses the intermediate transfer belt 421 against the photosensitive drum 413, a plurality of support rollers 423 including a backup roller 423A, and a belt cleaning device 426. The intermediate transfer belt 421 is stretched around the plurality of support rollers 423 in a loop. As at least one of the plurality of support rollers 423 rotates, the intermediate transfer belt 421 runs at a constant speed in the direction of arrow A.

  The secondary transfer unit 43 has an endless secondary transfer belt 432 and a plurality of support rollers 431 including a secondary transfer roller 431A. The secondary transfer belt 432 is stretched in a loop by the secondary transfer roller 431A and the support roller 431.

  The fixing device 60 includes, for example, a fixing roller 62, an endless heating belt 10 that covers an outer peripheral surface of the fixing roller 62, and heats and fuses a toner that forms a toner image on the sheet S, and fixes the sheet S. A pressure roller 63 for pressing the roller 62 and the heating belt 10. The paper S corresponds to a recording medium.

  The image forming apparatus 100 further includes an image reading unit 110, an image processing unit 30, and a sheet conveying unit 50. The image reading unit 110 has a paper feeding device 111 and a scanner 112. The paper transport unit 50 includes a paper feed unit 51, a paper discharge unit 52, and a transport path unit 53. In the three paper feed tray units 51a to 51c constituting the paper feed unit 51, paper S (standard paper, special paper) identified based on the basis weight, size, or the like is stored for each type set in advance. . The transport path unit 53 has a plurality of transport roller pairs such as a pair of registration rollers 53a.

The formation of an image by the image forming apparatus 100 will be described.
The scanner 112 optically scans and reads the document D on the contact glass. The reflected light from the document D is read by the CCD sensor 112a and becomes input image data. The input image data is subjected to predetermined image processing in the image processing unit 30 and sent to the exposure device 411.

  The photoconductor drum 413 rotates at a constant peripheral speed. The charging device 414 uniformly charges the surface of the photosensitive drum 413 to a negative polarity. In the exposure device 411, the polygon mirror of the polygon motor rotates at a high speed, and the laser light corresponding to the input image data of each color component is developed along the axial direction of the photosensitive drum 413, and the photosensitive member along the axial direction. The light is irradiated on the outer peripheral surface of the drum 413. Thus, an electrostatic latent image is formed on the surface of the photosensitive drum 413.

  In the developing device 412, the toner particles are charged by stirring and transporting the two-component developer in the developing container, and the two-component developer is transported to the developing roller to form a magnetic brush on the surface of the developing roller. The charged toner particles electrostatically adhere to the portion of the electrostatic latent image on the photosensitive drum 413 from the magnetic brush. Thus, the electrostatic latent image on the surface of the photosensitive drum 413 is visualized, and a toner image corresponding to the electrostatic latent image is formed on the surface of the photosensitive drum 413. The toner in the developing container is agitated by the transport, and receives the stress caused by the agitation. However, the toner has excellent crush resistance, so that the toner is not crushed by the transport.

  The toner image on the surface of the photosensitive drum 413 is transferred to the intermediate transfer belt 421 by the intermediate transfer unit 42. The transfer residual toner remaining on the surface of the photosensitive drum 413 after the transfer is removed by a drum cleaning device 415 having a drum cleaning blade slidably contacting the surface of the photosensitive drum 413.

  When the intermediate transfer belt 421 is pressed against the photosensitive drum 413 by the primary transfer roller 422, a primary transfer nip is formed for each photosensitive drum by the photosensitive drum 413 and the intermediate transfer belt 421. In the primary transfer nip, the toner images of each color are sequentially transferred onto the intermediate transfer belt 421 so as to overlap each other.

  On the other hand, the secondary transfer roller 431A is pressed against the backup roller 423A via the intermediate transfer belt 421 and the secondary transfer belt 432. Thereby, a secondary transfer nip is formed by the intermediate transfer belt 421 and the secondary transfer belt 432. The paper S is transported to the secondary transfer nip by the paper transport unit 50, and the paper S passes through the secondary transfer nip. The correction of the inclination of the sheet S and the adjustment of the conveyance timing are performed by a registration roller unit provided with a registration roller pair 53a.

  When the sheet S is transported to the secondary transfer nip, a transfer bias is applied to the secondary transfer roller 431A. By applying the transfer bias, the toner image carried on the intermediate transfer belt 421 is transferred to the sheet S. The sheet S on which the toner image has been transferred is conveyed toward the fixing device 60 by the secondary transfer belt 432.

  The fixing device 60 forms a fixing nip by the heating belt 10 and the pressure roller 63, and heats and presses the conveyed sheet S in the fixing nip portion. The toner particles constituting the toner image on the sheet S are heated, and the hybrid crystalline resin is quickly melted therein, as a result, the entire toner particles are quickly melted with a relatively small amount of heat, and the toner component Adheres to In the adhered molten toner component, the polyester polymerization segment in the hybrid crystalline resin is rapidly crystallized, and the entire molten toner component is quickly solidified. Thus, the toner image is quickly fixed on the sheet S with a relatively small amount of heat. The sheet S on which the toner image has been fixed is discharged out of the apparatus by a sheet discharging unit 52 provided with a sheet discharging roller 52a. Thus, a high-quality image is formed.

  The transfer residual toner remaining on the surface of the intermediate transfer belt 421 after the secondary transfer is removed by a belt cleaning device 426 having a belt cleaning blade slidably contacting the surface of the intermediate transfer belt 421.

As is clear from the above description, the toner contains at least toner base particles containing a binder resin containing a crystalline polyester, and as described above, the following formulas (1), (2) and (3). Satisfies both relationships. Therefore, the toner has a sufficient low-temperature fixability even in high-speed image formation by an electrophotographic method, has a high glossiness even in a paper type having a large basis weight, and has a toner particle and a fixed image. Both have thermal stability.
Formula (1) 0.01 ≦ ΔH1 / ΔHth <0.20
Formula (2) 0.06 ≦ ΔH2 / ΔHth <0.25
Formula (3) 55 <Tm <90

The fact that the toner further satisfies the following formula (4) is considered to be more effective from the viewpoint of suppressing the fluctuation of the image quality due to the fluctuation of the fixing temperature and the viewpoint of enhancing the storage stability of the image. It is considered that further satisfying the above condition) is more effective from the above viewpoint.
Formula (4) 0.10 ≦ ΔH2 / ΔHth ≦ 0.20
Formula (5): 0.12 ≦ ΔH2 / ΔHth ≦ 0.16

Further, it is considered that the toner further satisfies the following formula (6) from the viewpoint of suppressing a decrease in heat resistance and from the viewpoint of prompt melting of toner particles during fixing.
Equation (6) 0.05 ≦ ΔH1 / ΔHth ≦ 0.15

  Further, it is considered that ΔH1 of 2 J / g or more and less than 10 J / g is more effective from the viewpoint of compatibility between the melting property at the time of fixing the toner and the thermal stability at the time of storage of the toner. Is more than 3 J / g and less than 7 J / g is considered to be even more effective from the above viewpoint.

  Further, it is considered that the ΔHth of 25 J / g or more is more effective from the viewpoint of improving the low-temperature fixability. This is presumably because the presence of a sufficient amount of the linear aliphatic monomer plasticizes the amorphous resin even during fixing in a high-speed machine.

  Further, the binder resin further includes an amorphous resin, the amorphous resin is derived from a linear aliphatic polycarboxylic acid, a linear aliphatic polyhydric alcohol, and a linear aliphatic hydroxycarboxylic acid. Having a structure that is considered to be more effective from the viewpoint of thermal stability of the toner, and that the amorphous resin is an amorphous polyester having a linear aliphatic structure, It is considered more effective. This is presumed to be due to the effect of structural similarity, which cannot be explained solely from the SP value and polarity.For example, by using a linear aliphatic monomer as a monomer of the amorphous resin, the detailed mechanism is not clear. It is considered that the thermal stability as a toner can be maintained even in a state where the crystalline polyester has low crystallinity, that is, in a state where ΔH1 is small.

  Further, it is considered that the crystalline polyester is a hybrid crystalline polyester in which a crystalline polyester unit and an amorphous resin unit are chemically bonded to each other, from the viewpoint of low-temperature fixability. This is because even when ΔH1 / ΔHth is low, that is, the compatibility is high and the compatibility has advanced after heating, the crystalline polyester exists with some domains, and as a result, the crystallization during cooling This is considered to be advantageous for promotion.

  Further, it is considered that the above-mentioned hybrid crystalline polyester is a resin in which a crystalline polyester unit and an amorphous resin unit are bonded without via a nitrogen atom, which is more effective from the viewpoint of low-temperature fixability. Although the detailed mechanism is not clear, when the crystalline polyester unit and the amorphous resin unit are bonded via a nitrogen atom, the cohesive force is increased by hydrogen bonding and the like, and the crystallinity is increased. Incompatibility and crystallization of the polyester proceed, for example, when a urethane bond or a urea bond is mediated, the hydrogen bond is further strengthened, and packing tends to occur due to the planarity of the bond, resulting in excessive crystallization. It is considered that ΔH1 / ΔHth tends to be larger than a preferable range.

  Further, it is considered that the above-mentioned hybrid crystalline polyester is a resin in which a crystalline polyester unit and an amorphous vinyl-based resin unit are chemically bonded, which is more effective from the viewpoint of appropriately adjusting the crystallinity of the crystalline polyester. Can be This is presumably because the vinyl resin unit has a wide range of monomer choices and its thermal properties and molecular structure can be controlled.

Further, the toner satisfies the relationship of the following expression (7) further from the viewpoint of suppressing tacking due to a rise in toner temperature on the image surface immediately after discharging due to a high fixing temperature, and a high fixing linear velocity. In a high-speed machine, even when it is difficult to sufficiently increase the temperature of the toner inside the toner or in the vicinity of the interface with the paper, it is considered more effective because the crystalline resin can be more reliably melted.
Formula (7): 65 <Tm <80

  In the toner described above, the ratio (ΔH1 / ΔHth) of the crystalline polyester existing as the crystal domain in the toner particles and the ratio (ΔH2 / ΔHth) of the crystalline polyester existing as the crystal domain in the fixed image after heat fixing are respectively determined. By being in a specific range and the melting point of the crystalline polyester being specified in an appropriate range, sufficient high-temperature preservability and low-temperature fixability can be obtained, and crushing resistance can be obtained over a long period of time, and excellent. A fixed image having improved image storability can be formed.

  The present invention will be described more specifically with reference to the following Examples and Comparative Examples. Note that the present invention is not limited to the following examples.

[Synthesis of amorphous resin A1] (First-stage polymerization)
A solution prepared by dissolving 8 g of sodium dodecyl sulfate in 3 L of ion-exchanged water was charged into a 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction device, and stirred at a stirring speed of 230 rpm under a nitrogen stream. After raising the internal temperature to 80 ° C., a solution in which 10 g of potassium persulfate was dissolved in 200 g of ion-exchanged water was added, and the liquid temperature was again set to 80 ° C.

To the obtained solution, a monomer mixture obtained by mixing the following components in the following amounts was added dropwise over 1 hour, and thereafter, polymerization was carried out by heating and stirring at 80 ° C. for 2 hours to obtain resin fine particles x1. Was dispersed to prepare a resin fine particle dispersion X1.
480 g of styrene
250 g of n-butyl acrylate
Methacrylic acid 68g

(Second stage polymerization)
A solution prepared by dissolving 7 g of polyoxyethylene (2) sodium dodecyl ether sulfate in 1460 mL of ion-exchanged water was charged into a 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device, and heated to 98 ° C. .

To the obtained solution, the resin fine particle dispersion liquid X1 was added in an amount of 260 g based on the resin fine particle x1, and a monomer solution at 80 ° C. containing the following components in the following amount was added to the above solution, followed by circulation. A mechanical dispersing machine “CREAMIX” having a path (“MREAK”, manufactured by M Technic Co., Ltd., “CREAMIX” is a registered trademark of the company) was mixed and dispersed for one hour to prepare a dispersion liquid containing emulsified particles (oil droplets).
245 g of styrene
95 g of n-butyl acrylate
Methacrylic acid 35g
n-octyl-3-mercaptopropionate 4.0 g

  Next, to the obtained dispersion, an initiator solution obtained by dissolving 6 g of potassium persulfate in 200 mL of ion-exchanged water was added, and the system was heated and stirred at 82 ° C. for 1 hour to carry out polymerization. Was dispersed to prepare a resin fine particle dispersion X2.

(3rd stage polymerization)
To the resin fine particle dispersion X2, a solution prepared by dissolving 11 g of potassium persulfate in 400 mL of ion-exchanged water was added, and a monomer composition containing the following components in the following amounts at a temperature of 82 ° C. The solution was added dropwise over 1 hour, and after the addition, the mixture was heated and stirred for 2 hours to perform polymerization. Thereafter, the obtained dispersion was cooled to 28 ° C. Thus, an amorphous resin A1, which is an amorphous vinyl resin, was prepared.
Styrene 405g
160 g of n-butyl acrylate
33 g of methacrylic acid
n-octyl-3-mercaptopropionate 10 g

  Further, the above dispersion was designated as an aqueous dispersion B1 of the amorphous resin A1. The volume-based median diameter D50z of the resin fine particles in the aqueous dispersion B1 was measured and found to be 220 nm. The weight-average molecular weight Mw of the amorphous resin A1 was 32500.

[Synthesis of amorphous polyester A2]
The following components were charged in the following amounts into a reaction vessel equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a rectification column. “BPA-PO” represents 2,2-bis (4-hydroxyphenyl) propane propylene oxide 2 mol adduct, and “BPO-EO” represents 2,2-bis (4-hydroxyphenyl) propane ethylene oxide 2 Represents a molar adduct. Further, fumaric acid and terephthalic acid correspond to polyhydric carboxylic acids, and BPA-PO and BPO-EO correspond to polyhydric alcohols.
1.8 parts by mass of fumaric acid (FA) 29.2 parts by mass of terephthalic acid (TA) 58.2 parts by mass of BPA-PO 6.7 parts by mass of BPO-EO

  After raising the temperature of the obtained mixture to 190 ° C. over 1 hour and confirming that the mixture is uniformly stirred, the amount of the catalyst becomes 0.006% by mass based on the total amount of the polycarboxylic acid. The temperature of the mixture was raised from the same temperature to 240 ° C. over 6 hours while distilling off generated water, and when the temperature reached 240 ° C., trimellitic acid 1 was added to the mixture. After adding 0.6 parts by mass, the dehydration condensation reaction was continued until the acid value of the product reached 21 mgKOH / g while maintaining the temperature at 240 ° C. to carry out the polymerization reaction, whereby the non-crystalline polyester non-crystalline polyester was obtained. A crystalline resin A2 was obtained. The obtained amorphous polyester A2 had a number average molecular weight (Mn) of 3,600 and a glass transition point (Tg) of 62 ° C. The acid value, Mn and Tg of the amorphous resin A2 were measured as described above.

[Synthesis of Amorphous Polyesters A3 to A6]
The amount of fumaric acid to 3.4 parts by mass, the amount of terephthalic acid to 27.2 parts by mass, the amount of trimellitic acid to 0.9 parts by mass, the amount of BPA-PO to 56.8 parts by mass, Then, an amorphous resin A3 as an amorphous polyester was obtained in the same manner as in the synthesis of the amorphous polyester A2 except that the amount of BPO-EO was changed to 5.1 parts by mass. The Mn of the amorphous polyester A3 was 4900, and the Tg was 63 ° C.

  Further, in addition to fumaric acid and terephthalic acid, 7.2 parts by weight of adipic acid (AA) were added, and the amount of fumaric acid was reduced to 3.4 parts by weight, and the amount of terephthalic acid was reduced to 20.0 parts by weight. Synthesis of the amorphous polyester A2 except that the amount of the acid was changed to 1.2 parts by mass, the amount of BPA-PO was changed to 58.1 parts by mass, and the amount of BPO-EO was changed to 6.1 parts by mass. Similarly, amorphous resin A4, which is an amorphous polyester, was obtained. The Mn of the amorphous polyester A4 was 4,700, and the Tg was 57 ° C.

  Further, in addition to BPA-PO and BPO-EO, 4.8 parts by mass of 1,9-nonanediol (1,9-DN) was added, and the amount of fumaric acid was changed to 2.4 parts by mass, and the amount of terephthalic acid was changed to 2.4 parts by mass. To 30.2 parts by mass, the amount of BPA-PO to 50.9 parts by mass, and the amount of BPO-EO to 6.1 parts by mass, respectively, in the same manner as in the synthesis of the amorphous polyester A2. Thus, an amorphous resin A5 as an amorphous polyester was obtained. The Mn of the amorphous polyester A5 was 4,200, and the Tg was 58 ° C.

  Also, without adding fumaric acid, the amount of terephthalic acid to 21.1 parts by mass, the amount of trimellitic acid to 11.4 parts by mass, the amount of BPA-PO to 31.1 parts by mass, and BPO-EO Was changed to 28.6 parts by mass, and an amorphous resin A6 was obtained in the same manner as in the synthesis of the amorphous polyester A2. The Mn of the amorphous polyester A6 was 3,900, and the Tg was 59 ° C.

[Synthesis of amorphous resin A7]
In a 5 L four-necked flask equipped with a nitrogen introducing tube, a dehydrating tube, a stirrer, and a thermocouple, a molar ratio of L-lactide to D-lactide (L-lactide: D-lactide) is 90:10. 100 parts by mass, 0.5 parts by mass of ethylene glycol, and a reaction with tin 2-ethylhexanoate (200 mass ppm with respect to the resin component) as a catalyst at 190 ° C. for 4 hours, followed by cooling to 175 ° C. The mixture was reacted at a pressure of 0.3 kPa for 2 hours to obtain an amorphous resin A7. The Mw of the amorphous resin A7 was 28,000, the Mw / Mn was 2.4, and the glass transition temperature Tg was 54 ° C. In addition, the amorphousness of the amorphous resin A7 is confirmed by a broad peak in a diffraction spectrum by an X-ray diffraction method that spreads widely over a measurement region.

  Table 1 shows the types and amounts of the monomers of the amorphous polyesters A2 to A7.

[Preparation of Aqueous Dispersion B2 of Amorphous Polyester Fine Particles]
240 parts by mass of methyl ethyl ketone and 60 parts by mass of isopropyl alcohol (IPA) were added to a reaction vessel equipped with an anchor blade for providing stirring power, and nitrogen was sent into the reaction vessel to replace air in the reaction vessel with nitrogen. Subsequently, 300 parts by mass of the amorphous polyester A2 was slowly added to the mixture while the mixture in the reaction vessel was heated to 60 ° C. with an oil bath apparatus, and dissolved with stirring. Next, after adding 20 parts by mass of 10% ammonia water to the obtained mixture, 1500 parts by mass of deionized water was added to the obtained mixture while stirring using a metering pump. It was confirmed that emulsification was carried out by the obtained liquid mixture exhibiting a milky white color and having reduced stirring viscosity.

  Thereafter, the obtained emulsion is pumped up by a differential pressure based on centrifugal force, and transferred to a separable flask equipped with a stirring blade that forms a wetted wall on a wall in the reaction tank, a reflux device, and a decompression device using a vacuum pump. The solvent and the dispersion medium in the emulsion were distilled off while keeping the temperature of the wall in the reaction vessel at 58 ° C. and stirring under reduced pressure, and the obtained dispersion reached 1,000 parts by mass. Was used as the end point of the distillation, the internal pressure of the reaction vessel was set to normal pressure, and the dispersion was cooled to room temperature while stirring to obtain an aqueous dispersion B2 of fine particles of amorphous polyester A2 having a solid content of 30% by mass. .

  The volume-based median diameter (D50v) of the resin fine particles dispersed in the aqueous dispersion B2 was 162 nm.

[Preparation of Aqueous Dispersions B3 to B7 of Amorphous Polyester Fine Particles]
An aqueous dispersion in which fine particles of each of the amorphous polyesters A3 to A7 are dispersed in the same manner as in the preparation of the aqueous dispersion B2 except that each of the amorphous polyesters A3 to A7 is used instead of the amorphous polyester A2. B3 to B7 were prepared respectively. D50v of the resin fine particles in the aqueous dispersions B3 to B7 was all within the range of 150 to 350 nm.

[Synthesis of crystalline polyester C1]
The following components were charged in the following amounts into a reaction vessel equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a rectification column. Sebacic acid corresponds to a polycarboxylic acid.
Sebacic acid (SA) 205 parts by mass Ethylene glycol 61 parts by mass

After raising the temperature of the mixture to 190 ° C. over 1 hour and confirming that the mixture is uniformly stirred, the amount of the catalyst becomes 0.006% by mass based on the total amount of the polycarboxylic acid. Of Ti (OBu) ₄ was charged into the reaction vessel, and the temperature of the mixture was raised from the same temperature to 240 ° C. over 6 hours while distilling off generated water, and further maintained at 240 ° C. The dehydration-condensation reaction was continued until the acid value of the product reached 20 mgKOH / g, and the polymerization reaction was carried out to obtain a crystalline polyester C1.

  The number average molecular weight (Mn) of the obtained crystalline polyester C1 was 3100, and the melting point (Tm) was 75 ° C. The acid value, number average molecular weight and melting point of the crystalline polyester C1 were measured as described above.

[Synthesis of crystalline polyesters C2 to C5, C8 and C12]
Synthesis of crystalline polyester C1 except that 177 parts by mass of dodecanedioic acid (DDA) was used as polyhydric carboxylic acid and 89 parts by mass of 1,6-hexanediol (1,6-DH) was used as polyhydric alcohol. In the same manner as in the above, a crystalline polyester C2 was obtained. Mn of the crystalline polyester C2 was 3,600, and Tm was 69 ° C.

  In addition, a crystalline polyester C1 was used except that 158 parts by mass of dodecane diacid (DDA) was used as the polyhydric carboxylic acid and 108 parts by mass of 1,9-nonanediol (1,9-DN) was used as the polyhydric alcohol. Crystalline polyester C3 was obtained in the same manner as in the synthesis of. Mn of the crystalline polyester C3 was 3900, and Tm was 68 ° C.

  A crystalline polyester C4 was obtained in the same manner as in the synthesis of the crystalline polyester C1, except that the amount of sebacic acid was changed to 169 parts by mass and 97 parts by mass of 1,6-hexanediol was used as the polyhydric alcohol. Was. Mn of the crystalline polyester C4 was 3,800, and Tm was 61 ° C.

  Further, a crystalline polyester C1 was obtained except that 153 parts by mass of dodecane diacid (DDA) was used as the polyhydric carboxylic acid and 113 parts by mass of 1,10-decanediol (1,10-DD) was used as the polyhydric alcohol. Crystalline polyester C5 was obtained in the same manner as in the synthesis of. Mn of the crystalline polyester C5 was 3,300, and Tm was 82 ° C.

  Further, 87 parts by mass of fumaric acid and 36.5 parts by mass of adipic acid are used as the polycarboxylic acid, and 81 parts by mass of 1,4-butanediol (1,4-DB) and 11.8 parts are used as the polyhydric alcohol. A crystalline polyester C8 was obtained in the same manner as in the synthesis of the crystalline polyester C1, except that 1,6-hexanediol in parts by mass was used. Mn of the crystalline polyester C8 was 3,400, and Tm was 115 ° C.

  Further, a crystalline polyester C12 was obtained in the same manner as in the synthesis of the crystalline polyester C1, except that 210 parts by mass of dodecanedioic acid was used instead of sebacic acid and the amount of ethylene glycol was changed to 56 parts by mass. Mn of the crystalline polyester C12 was 4100, and Tm was 84 ° C.

[Synthesis of crystalline polyester C6]
In a 10-liter four-necked flask equipped with a nitrogen introducing tube, a dehydrating tube, a stirrer, and a thermocouple, 142 parts by mass of dodecandioic acid and 97 parts by mass of 1,9-nonanediol were put, and heated to 160 ° C. Was dissolved.

To the resulting solution, a mixed solution containing the following components in the following amounts was dropped by a dropping funnel over 1 hour, and after the dropping, the mixture was kept at 170 ° C. and stirred for 1 hour to remove the vinyl monomer. Polymerized.
Styrene 21.5 parts by mass 2-Ethylhexyl acrylate 5.2 parts by mass Acrylic acid 0.3 parts by mass Dicumyl peroxide 0.6 parts by mass

Next, Ti (OBu) ₄ was added to the resulting mixed solution in an amount of 0.006% by mass based on the total amount of the polyvalent carboxylic acid (dodecane diacid), and the mixture was heated to 210 ° C. and reacted for 8 hours. Was done. The reaction was further performed at 8.3 kPa for 1 hour to obtain a crystalline polyester C6 which is a vinyl-modified crystalline polyester. Mn of the crystalline polyester C6 was 4,200, and Tm was 67 ° C.

[Synthesis of crystalline polyester C7]
The amount of dodecanedioic acid to 126 parts by mass, the amount of 1,9-nonanediol to 86 parts by mass, the amount of styrene to 42.9 parts by mass, the amount of 2-ethylhexyl acrylate to 10.7 parts by mass, Crystalline polyester C7 was synthesized in the same manner as in the synthesis of crystalline polyester C6, except that the amount of acrylic acid was changed to 0.4 part by mass and the amount of dicumyl peroxide was changed to 1.0 part by mass. Mn of the crystalline polyester C7 was 4,400, and Tm was 67 ° C.

[Synthesis of crystalline polyester C9]
In a 5 L four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple, sebacic acid and 1,4-butanediol were placed in a molar ratio of hydroxyl group to carboxyl group (OH / COOH). ) Was set to 1.2, and reacted with titanium tetraisopropoxide (500 mass ppm with respect to the resin component) at 190 ° C. for 12 hours, and then heated to 200 ° C. and reacted for 3 hours. The mixture was further reacted at a pressure of 7.5 kPa for 2 hours to obtain a crystalline polyester C9. Mw of the crystalline polyester C9 was 12000, Mw / Mn was 3.0, and Tm was 62 ° C.

[Synthesis of crystalline polyester C10]
In a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, the crystalline polyester C9 and the amorphous resin A7 were mixed at a ratio of the mass of the crystalline polyester C9 to the mass of the amorphous resin A7 of 30 / 70. Further, isophorone diisocyanate (IPDI) was added to the reaction tank so that the molar ratio of the isocyanate groups became 0.65, and the mixture was diluted with ethyl acetate so that the concentration of the above additive became 50% by mass. Then, the reaction was carried out at 80 ° C. for 5 hours under a nitrogen stream. Then, ethyl acetate was distilled off under reduced pressure. Thus, a crystalline polyester C10 was obtained. The Mw of the crystalline polyester C10 was 35,000, the Mw / Mn was 2.2, the glass transition temperature Tg was 34 ° C., and Tm was 60 ° C.

  The “molar ratio of the isocyanate groups” is defined as OHa (mol) which is the sum of the number of moles of a carboxyl group and a hydroxyl group obtained from the hydroxyl value of the crystalline polyester C9, and the hydroxyl value of the amorphous resin A7. It is a ratio (NCO / (OHa + OHb)) of the number of moles (mol) of the isocyanate group of the IPDI to OHb (mol), which is the sum of the number of moles of the carboxy group and the number of moles of the hydroxyl group.

[Synthesis of crystalline polyester C11]
In the same manner as in the synthesis of the crystalline polyester C7, except that 135 parts by mass of sebacic acid is used in place of dodecanediacid and 77 parts by mass of 1,6-hexanediol in place of 1,9-nonanediol, respectively. A crystalline polyester C11 was synthesized. Mn of the crystalline polyester C11 was 4,500, and Tm was 57 ° C.

  Table 2 shows the types, amounts, and melting points of the monomers in the crystalline polyesters C1 to C12.

[Preparation of aqueous dispersion D1 of crystalline polyester fine particles]
300 parts by mass of the crystalline polyester C1 was melted and transferred in a molten state to an emulsifying and dispersing machine “Cavitron CD1010” (manufactured by Eurotech Co., Ltd.) at a transfer rate of 15 parts per minute. Simultaneously with the transfer of the crystalline polyester C1 in the molten state, 700 parts by mass of dilute ammonia water having a concentration of 0.37% by mass was heated to 100 ° C. by a heat exchanger at a rate of 35 parts by mass per minute. At a transfer speed of. The diluted ammonia water was obtained by diluting the reagent ammonia water with ion-exchanged water in an aqueous solvent tank.

By operating this emulsifying and dispersing machine under the conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² (490.35 kPa), the volume-based median diameter D50v is 200 nm, and the solid content is 30 mass%. % Of a crystalline polyester C1 dispersed therein.

[Preparation of aqueous dispersions D2 to D12 of crystalline polyester fine particles]
Each of the aqueous dispersions D2 to D12 in which the fine particles of the crystalline polyesters C2 to C12 are dispersed in the same manner as in the preparation of the aqueous dispersion D1 except that each of the crystalline polyesters C2 to C12 is used instead of the crystalline polyester C1. Was prepared. D50v of each of the aqueous dispersions D2 to D12 was in the range of 180 to 380 nm.

[Preparation Example of Aqueous Dispersion Bk of Colorant Fine Particles]
90 parts by mass of sodium polyoxyethylene-2-dodecyl ether sulfate was added to and dissolved in 1510 parts by mass of ion-exchanged water. While stirring this solution, 400 parts by mass of carbon black "REGAL 330" (manufactured by Cabot) is gradually added, and then, a stirrer "CLEARMIX" (manufactured by M Technic Co., Ltd., "CLEARMIX" is manufactured by (Registered trademark) to prepare an aqueous dispersion Bk, which is an aqueous dispersion of colorant fine particles having a solid content of 20% by mass. The average particle diameter (volume-based median diameter D50v) of the colorant fine particles in the aqueous dispersion Bk was measured using "Microtrac UPA-150" (manufactured by Nikkiso Co., Ltd.) and found to be 110 nm.

[Preparation of aqueous dispersion liquids W1 to W3 of release agent fine particles]
50 parts by mass of "Nissan Elektor WEP-3" (manufactured by NOF CORPORATION, melting point (Tm): 73C, "Nissan Elektor" and "WEP" are registered trademarks of the same company), polyoxyethylene-2- 5 parts by mass of sodium dodecyl ether sulfate and 195 parts by mass of ion-exchanged water are mixed, heated to 90 ° C., sufficiently dispersed with a homogenizer “Ultra Turrax T50” (manufactured by IKA), and a pressure discharge type Gaulin homogenizer is added. By performing a dispersion treatment using the same, an aqueous dispersion W1 which is an aqueous dispersion of the release agent fine particles was prepared. The volume-based median diameter D50v of the release agent fine particles in the aqueous dispersion W1 was 170 nm. "Nissan Elektor WEP-3" is a purified product containing behenyl behenate (BB) as a main component.

  Preparation of an aqueous dispersion W1 except that carnauba wax (CW, “Purified Carnauba Wax No. 1” (manufactured by Cera Rica NODA), Tm: 83 ° C.) was used instead of “Nissan Elektor WEP-3”. Similarly, an aqueous dispersion W2 was prepared. D50v of the release agent fine particles in the aqueous dispersion W2 was 193 nm.

  An aqueous dispersion was used except that paraffin wax ("NNP-9" manufactured by Nippon Seiro Co., Ltd., Tm: 75 ° C, "HNP" is a registered trademark of the company) was used instead of "Nissan Elektor WEP-3". An aqueous dispersion W3 was prepared in the same manner as in the preparation of the liquid W1.The D50v of the release agent fine particles in the aqueous dispersion W3 was 168 nm.

Example 1 Production of Toner Particle 1
In a reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device, 1667 parts by mass of an aqueous dispersion B1 of amorphous resin fine particles (500 parts by mass in solid content) and 667 parts by mass of an amorphous resin Aqueous dispersion B2 of fine particles (200 parts by mass in solid content), 350 parts by mass of aqueous dispersion Bk of colorant particles (70 parts by mass in solid content), 400 parts by mass of aqueous dispersion of release agent particles in W1 ( A solid content of 80 parts by mass) and 3500 parts by mass of ion-exchanged water were added, and while stirring, a 5 mol / L aqueous sodium hydroxide solution was added to the obtained mixture to adjust the pH of the mixture to 11 ( 20 ° C).

  Next, an aqueous solution obtained by dissolving 160 parts by mass of magnesium chloride in 160 parts by mass of ion-exchanged water was added to the mixture at a rate of 10 parts by mass / minute. After standing for 5 minutes, 500 parts by weight of an aqueous dispersion D2 of crystalline polyester fine particles (150 parts by weight in terms of solid content) was added to the obtained mixture at a rate of 25 parts by weight / minute. After standing for 5 minutes, the temperature of the obtained mixed liquid was started, and the temperature was raised to 70 ° C. over 60 minutes to start an aggregation reaction. After the start of the agglutination reaction, sampling is performed periodically, and a volume-based median diameter D50v of the generated agglomerated particles is measured using a particle size distribution analyzer “Coulter Multisizer 3” (manufactured by Beckman Coulter, Inc.). While lowering the stirring speed as necessary, stirring was continued until D50v became 6.3 μm, and the agglutination reaction was continued.

  When the D50v became 6.3 μm, the stirring speed was increased again, and an aqueous solution in which 300 parts by mass of sodium chloride was dissolved in 1200 parts by mass of ion-exchanged water was added to the mixture, and the temperature of the mixture was lowered. Stirring was continued at 80 ° C., and the average circularity of the particles in the mixture was measured by a flow-type particle image analyzer “FPIA-2100” (manufactured by Sysmex Corporation, “FPIA” is a registered trademark of the company). When the temperature reached 0.946, the mixture was cooled to 30 ° C. at a rate of 6 ° C./min to stop the agglutination reaction, and a dispersion of colored particles was obtained. The particle size (D50v) of the colored particles after cooling was 6.1 μm, and the average circularity was 0.946.

  The dispersion liquid of the obtained colored particles was subjected to solid-liquid separation using a basket-type centrifugal separator “MARK III Model No. 60 × 40” (manufactured by Matsumoto Machine Co., Ltd.) to obtain a wet cake. The obtained wet cake is repeatedly washed and solid-liquid separated by the basket type centrifuge until the electric conductivity of the filtrate becomes 15 μS / cm, and the washed cake is subjected to “flash jet dryer” (Seishin Co., Ltd.). Was dried little by little by blowing an air current at a temperature of 40 ° C. and a humidity of 20% RH until the water content became about 2.0% by mass, and then cooled to 24 ° C. Thereafter, the cake was transferred to a “vibrating fluidized bed apparatus” (manufactured by Chuo Kakoki Co., Ltd.), and the cake was dried at a temperature at which the temperature of the cake became 40 ° C. for 2 hours, so that the water content was 0.5%. The following toner base particles 1X were obtained.

  To the obtained toner base particles 1X, 1% by mass of hydrophobic silica and 1.2% by mass of hydrophobic titanium oxide were added, and the peripheral speed of the rotor was set to 24 mm / h using a "Henschel mixer" (manufactured by Nippon Coke Industries, Ltd.). For 20 minutes, and then subjected to an external additive treatment for removing coarse particles using a 400-mesh sieve, whereby toner particles 1 were produced.

  To the toner particles 1, a ferrite carrier coated with a silicone resin and having a volume average particle diameter of 60 μm was added and mixed so that the toner particle concentration became 6% by mass. Thus, Toner 1 as a two-component developer was manufactured.

Examples 2 and 3: Production of Toners 2 and 3
Toner 2 was produced in the same manner as in the production of Toner 1, except that the aqueous dispersion B3 was used instead of the aqueous dispersion B2. Further, a toner 3 was produced in the same manner as in the production of the toner 1, except that the aqueous dispersion B4 was used instead of the aqueous dispersion B2.

Example 4 Production of Toner 4
Toner 4 was produced in the same manner as in the production of Toner 1, except that the aqueous dispersion B1 having a solid content of 700 parts by mass was used instead of the aqueous dispersion B1 and the aqueous dispersion B2.

[Examples 5 to 7: Production of Toners 5 to 7]
Toner 5 was produced in the same manner as in the production of Toner 2, except that the aqueous dispersion B2 was used instead of the aqueous dispersion B1. Further, a toner 6 was produced in the same manner as in the production of the toner 5, except that the aqueous dispersion B4 was used instead of the aqueous dispersion B3. Further, a toner 7 was produced in the same manner as in the production of the toner 5 except that the aqueous dispersion B5 was used instead of the aqueous dispersion B3.

[Examples 8 and 9: Production of Toners 8 and 9]
A toner 8 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D6 was used instead of the aqueous dispersion D2. Further, a toner 9 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D7 was used instead of the aqueous dispersion D2.

[Examples 10 to 12: Production of Toners 10 to 12]
Same as in the production of toner 1 except that the aqueous dispersion B1 and the aqueous dispersion B2 were replaced with 600 parts by weight of the aqueous dispersion B2 in terms of solid content, and the amount of the aqueous dispersion D2 was changed to 250 parts by weight in terms of the solid content. Thus, a toner 10 was manufactured. Further, the toner 11 was manufactured in the same manner as the toner 10 except that the amount of the aqueous dispersion B2 was changed to 750 parts by mass on a solid basis and the amount of the aqueous dispersion D2 was changed to 100 parts by mass on a solid basis. did. Further, the toner 12 was produced in the same manner as the production of the toner 10 except that the amount of the aqueous dispersion B2 was changed to 800 parts by mass on a solid basis and the amount of the aqueous dispersion D2 was changed to 50 parts by mass on a solid basis. did.

[Examples 13 to 16: Production of toners 13 to 16]
A toner 13 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D1 was used instead of the aqueous dispersion D2. Further, a toner 14 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D3 was used instead of the aqueous dispersion D2. Further, a toner 15 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D4 was used instead of the aqueous dispersion D2. Further, a toner 16 was produced in the same manner as in the production of the toner 7, except that the aqueous dispersion D5 was used instead of the aqueous dispersion D2.

[Examples 17 to 20: Production of Toners 17 to 20]
A toner 17 was produced in the same manner as in the production of the toner 15, except that the amount of the aqueous dispersion B2 was changed to 550 parts by mass in terms of solid content, and the amount of the aqueous dispersion D4 was changed to 100 parts by mass. Toners 18 and 20 were produced in the same manner as in the production of the toner 15, except that the aqueous dispersions D11 and D12 were used instead of the aqueous dispersion D4. Further, a toner 19 was produced in the same manner as the production of the toner 18 except that the cooling rate of the mixture after the average circularity of the aggregated particles reached 0.946 was changed from 6 ° C./min to 30 ° C./min. .

[Examples 21 to 23: Production of Toners 21 to 23]
Toner 21 was produced in the same manner as in the production of toner 15, except that the cooling rate of the mixture after the average circularity of the aggregated particles reached 0.946 was changed from 6 ° C./min to 30 ° C./min. Further, a toner 22 was produced in the same manner as in the production of the toner 13 except that the cooling rate was changed from 6 ° C./min to 15 ° C./min. Further, a toner 23 was produced in the same manner as in the production of the toner 13 except that the cooling rate was changed from 6 ° C./min to 30 ° C./min.

[Examples 24 and 25: Production of Toners 24 and 25]
A toner 24 was produced in the same manner as in the production of the toner 13 except that the amount of the aqueous dispersion B2 was changed to 550 parts by mass in terms of solid content, and the amount of the aqueous dispersion D1 was changed to 100 parts by mass. Further, a toner 25 was produced in the same manner as in the production of the toner 4, except that the amount of the aqueous dispersion B2 was changed to 717 parts by mass in terms of solid content and the amount of the aqueous dispersion D2 was changed to 133 parts by mass.

[Comparative Example 1: Production of Toner 26]
Toner 26 was produced in the same manner as in the production of toner 1, except that the aqueous dispersion B1 having a solid content of 700 parts by mass was used instead of the aqueous dispersion B1 and the aqueous dispersion B2.

[Comparative Example 2: Production of Toner 27]
Toner 27 was produced in the same manner as in the production of toner 15, except that the amounts of the aqueous dispersion B2 and the aqueous dispersion B5 were both changed to 350 parts by mass in terms of solid content.

[Comparative Example 3: Production of Toner 28]
740 parts by mass of the aqueous dispersion B6 in solid content was used in place of the aqueous dispersions B1 and B2, and 130 parts by mass of the aqueous dispersion D8 in solid content was used in place of the aqueous dispersion D2. Toner 28 was produced in the same manner as in the production of Toner 1 except that the amount of Bk was changed to 87 parts by mass in terms of solid content, and an aqueous dispersion W2 having a solid content of 43 parts by mass was used instead of the aqueous dispersion W1. .

[Comparative Example 4: Production of Toner 29]
Instead of the aqueous dispersion B1 and the aqueous dispersion B2, an aqueous dispersion B7 having a solid content of 50 parts by mass was used. Instead of the aqueous dispersion D2, an aqueous dispersion D9 having a solid content of 100 parts by mass and a solid content of 750 masses were used. Part of the aqueous dispersion D10, the amount of the aqueous dispersion Bk was changed to 50 parts by mass in terms of solid content, and the aqueous dispersion W3 was replaced with 50 parts by mass in terms of solids in place of the aqueous dispersion W1. In the same manner as in the production of No. 1, a toner 29 was produced.

  Tables 3 and 4 show the material compositions of the toner base particles in Toners 1 to 29.

[Evaluation]
(1) Calculation of ΔH1, ΔH2, and ΔHth For each of the toner particles 1 to 29, differential scanning calorimetry was performed as described above using “Diamond DSC” (manufactured by PerkinElmer), and ΔH1 was determined based on the measurement results. And ΔH2 were calculated. The enthalpy of fusion ΔHth (J / g) of each of the toner particles 1 to 29 was calculated by the atomic group contribution method as described above.

(2) Low-temperature fixability “bizhub PRESS 1250” (manufactured by Konica Minolta Co., Ltd., “bizhub” is a registered trademark of the company) can be used to measure the temperature of the heating belt 10 immediately after the fixing nip when passing paper, and Using a remodeling machine in which the fixing linear speed can be adjusted regardless of the basis weight, the paper passing speed of each of the toners 1 to 29 under the environment of normal temperature and normal humidity (temperature 20 ° C., humidity 50% RH) A4 size coated paper with a basis weight of 350 g is conveyed vertically at a speed of 570 mm / sec, and 100 continuous A4 images having a 10 mm wide solid black band image perpendicular to the conveyance direction are printed on the coated paper. A fixing experiment was performed in which the fixing temperature was set to 100 ° C., 105 ° C.,.

  In the fixing experiment at each fixing temperature, the fixing performance was evaluated with the image printed at the lowest fixing temperature when the temperature decrease at the start occurred, and the lowest temperature was set as the fixing temperature at the set temperature. . Among the above images in which the image stain due to the fixing offset was not visually confirmed, the fixing temperature of the image having the lowest fixing temperature was defined as the lowest fixing temperature. When the minimum fixing temperature is less than 135 ° C., the toner is excellent in low-temperature fixability. When the minimum fixing temperature is 135 ° C. or more and less than 150 ° C., there is no practical problem. If the temperature is 150 ° C. or higher and lower than 155 ° C., the toner can be used under the control of the fixing process, so that the toner is acceptable. There is a certain level.

(3) Gloss stability For each of the toners 1 to 29, the set value of the fixing temperature + 10 ° C. when the image stain due to the fixing offset is not visually observed in the low-temperature fixing property test using the above-described modified machine is shown. An image is taken as the set fixing temperature, the glossiness between the image at the lowest temperature at the set fixing temperature and the 100th image is measured, the absolute value (GU) of the difference is obtained, and based on the absolute value, The gloss stability was evaluated according to the following criteria.
A: Difference in glossiness is less than 5. Visually acceptable level (pass).
：: Difference in glossiness is 5 or more and less than 10. Level that has no practical problem (passed).
Δ: Difference in glossiness is 10 or more and less than 13. Depending on the type of the original image, the gloss difference can be confirmed by comparing the images side by side, but the level is acceptable (pass).
X: The difference in glossiness is 13 or more. Level with practical problems (fail).

(4) Image preservability (resistance to document offset)
For each of the toners 1 to 29, the set value + 15 ° C. when the image stain due to the fixing offset is not visually observed in the low-temperature fixing property test using the above-described modified machine is set as the set temperature of the fixing temperature. 100 double-sided prints of transfer paper were continuously output at a linear speed of 570 mm / sec. In the double-sided printing, a solid image with a toner adhesion amount of 5 mg / cm ² is fixed on one side of the transfer paper, and a character image in which the upper half of the line is printed with 36 lines of an alphabet of 6.0 points is fixed on another side. In addition to fixing, a solid image having a toner adhesion amount of 5 mg / cm ² was fixed on the lower half thereof.

Then, the output 100 printed materials were arranged on a marble table as they were, and a weight was placed on the overlapped portion so as to apply a pressure equivalent to 19.6 kPa (200 g / cm ² ). In this state, after leaving for 3 days in an environment of a temperature of 30 ° C. and a humidity of 60% RH, the superposed fixed images were peeled off, and the degree of image defects on the superposed fixed images was evaluated according to the following evaluation criteria. If the result is “◎”, “○”, or “△”, the test is passed.
A: Image defect due to toner transfer and slight sticking between fixed images were not observed, and there was no problem of image loss (excellent).
：: A crisp sound was made when the two prints in the stacked state were separated, but there was no image defect and there was no problem of image loss (good).
Δ: Slight gross unevenness was observed on the fixed image when the two prints in the superposed state were separated, but there was no image defect and there was almost no image loss (practicable ).
×: Image migration was observed on the background area of the character image, or the character image also migrated to the background part in contact with the character image, and loss of the character image and occurrence of convex parts in the background part were confirmed. Level (bad).

(5) Crush resistance For each of the toners 1 to 29, the above-mentioned modified machine was used in an L / L environment (temperature of 10 ° C., humidity of 15% RH) and an H / H environment (temperature of 30 ° C., humidity of 85% RH). After printing 100,000 sheets of a character image with a printing rate of 10% continuously, print one halftone image, and observe the fog of a white background portion and the image roughness of the image portion of the halftone image visually and with a 20 × magnifier. And evaluated according to the following evaluation criteria.
A: Neither image roughness nor fogging was confirmed by observation with a 20 × loupe (pass).
：: Image roughness and / or fogging were slightly observed with a 20-fold loupe, but at a level having no practical problem (pass).
Δ: Image roughness and / or fog were visually observed when carefully observed, but at an acceptable level (pass).
X: Image roughness and fog were sufficiently confirmed visually, and there was a practical problem (fail).

(6) High Temperature Storage Property For each of the toners 1 to 29, 0.5 g of the toner is placed in a 10 mL glass bottle having an inner diameter of 21 mm, the lid is closed, and a shaking machine “Tap Denser KYT-2000” (manufactured by Seishin Enterprise Co., Ltd.) is used. After shaking 600 times at room temperature, the sample was left for 2 hours in an environment of a temperature of 55 ° C. and a humidity of 35% RH with the lid open. Next, the entire amount of the toner in the glass bottle is placed on a 48-mesh (350 μm mesh) sieve, taking care not to break up the aggregates of the toner, and set in a “powder tester” (manufactured by Hosokawa Micron Corporation). Then, the sieve was fixed with a holding bar and a knob nut, and was vibrated for 10 seconds at a vibration intensity of a feed width of 1 mm, and the ratio (mass%) of the amount of toner passing through the sieve was measured. Was calculated. The high-temperature preservability of the toner was evaluated based on the obtained sieve passing rate. Those having a sieve passing rate of 80% or more were judged to be acceptable. In the following formula, W0 represents the mass (g) of the toner measured on the sieve, and W1 represents the mass (g) of the toner remaining on the sieve.
Formula: Sieve passing rate (%) = {(W0−W1) / W0} × 100

  Tables 5 and 6 show the evaluation results of the toners 1 to 29, respectively.

  As is clear from Tables 5 and 6, Toners 1 to 25 have sufficient performance in all of low-temperature fixing property, gloss stability, image storage property, crush resistance and high-temperature storage property.

  On the other hand, the toner 26 had insufficient crush resistance and low-temperature fixability. This is because ΔH1 / ΔHth is too high, there are many interfaces between the amorphous resin and the crystalline polyester, the toner is crushed by stress in the developing machine, and the melting of the crystalline polyester is insufficient at the time of fixing. ,it is conceivable that.

  Further, the toner 27 had insufficient image storability and high-temperature storability. This is probably because ΔH2 / ΔHth was too low, the crystalline polyester in the fixed image was insufficiently crystallized, and the fixed image was in a plasticized state. Further, it is considered that because ΔH2 / ΔHth was too low, a part of the crystalline polyester having a low melting point became compatible during the above-mentioned test, and as a result, the high-temperature preservability was reduced.

  Further, the toner 28 had insufficient low-temperature fixability. This is probably because both ΔH1 / ΔHth and Tm were too high, and the melting of the crystalline polyester was insufficient, so that sufficient fixability was not exhibited.

  Further, the toner 29 had insufficient gloss stability and low-temperature fixability. This is because the ΔH1 / ΔHth is too high, the melting of the crystalline polyester is insufficient, and the absolute amount of the crystalline polyester is large. It is considered that the change in glossiness caused by scattering near the crystalline polyester remaining without melting became more remarkable.

  ADVANTAGE OF THE INVENTION According to this invention, the low-temperature fixing property and the crush resistance of the toner are exhibited, and the fluctuation of gloss due to the fluctuation of the temperature condition during fixing is suppressed. According to the present invention, higher quality, higher speed, and energy saving in electrophotographic image forming technology are expected, and further spread of the image forming technology is expected.

DESCRIPTION OF SYMBOLS 10 Heating belt 30 Image processing part 40 Image formation part 41Y, 41M, 41C, 41K Image formation unit 42 Intermediate transfer unit 43 Secondary transfer unit 50 Paper conveyance part 51 Paper supply part 51a, 51b, 51c Paper supply tray unit 52 Paper discharge Unit 52a Discharge roller 53 Transport path unit 53a Registration roller pair 60 Fixing device 62 Fixing roller 63 Pressure roller 100 Image forming device 110 Image reading unit 111 Paper feeding device 112 Scanner 112a CCD sensor 411 Exposure device 412 Developing device 413 Photoconductor drum 414 Charging device 415 Drum cleaning device 421 Intermediate transfer belt 422 Primary transfer roller 423, 431 Support roller 423A Backup roller 426 Belt cleaning device 431A Secondary transfer roller 432 Secondary transfer belt D Document S Paper

Claims (12)

In a toner for developing an electrostatic latent image containing toner base particles containing at least a binder resin,
The binder resin includes a crystalline polyester,
The binder resin further includes an amorphous resin,
The amorphous resin has a structure derived from a linear aliphatic polycarboxylic acid, a linear aliphatic polyhydric alcohol, and a linear aliphatic hydroxycarboxylic acid,
However, the amorphous resin does not include an amorphous polyester resin containing a polyhydroxycarboxylic acid skeleton in part of the main chain,
Which satisfies any of the following equations (1), (2) and (3):
toner.
Formula (1) 0.01 ≦ ΔH1 / ΔHth <0.20
Formula (2) 0.06 ≦ ΔH2 / ΔHth <0.25
Formula (3) 55 <Tm <90
(In the above formula, ΔHth represents a melting enthalpy (J / g) calculated by an atomic group contribution method from a weight ratio of a molecular structure derived from a linear aliphatic monomer contained in the toner, and ΔH1 is a Represents the endothermic amount (J / g) of the endothermic peak of the crystalline polyester in the first heating step in the differential scanning calorimetry, and ΔH2 is the second heating step in the differential scanning calorimetry of the toner. (It represents the endothermic amount (J / g) of the endothermic peak of the crystalline polyester, and Tm represents the melting point (° C.) of the crystalline polyester.) The toner according to claim 1, further satisfying the following expression (4).
Formula (4) 0.10 ≦ ΔH2 / ΔHth ≦ 0.20 The toner according to claim 1, further satisfying the following formula (5).
Formula (5): 0.12 ≦ ΔH2 / ΔHth ≦ 0.16 The toner according to any one of claims 1 to 3, further satisfying the following formula (6).
Equation (6) 0.05 ≦ ΔH1 / ΔHth ≦ 0.15   The toner according to any one of claims 1 to 4, wherein ΔH1 is 2 J / g or more and less than 10 J / g.   The toner according to any one of claims 1 to 5, wherein ΔH1 is 3 J / g or more and less than 7 J / g.   The toner according to any one of claims 1 to 6, wherein ΔHth is 25 J / g or more. The toner according to any one of claims 1 to 7 , wherein the amorphous resin is an amorphous polyester having a linear aliphatic structure. The toner according to any one of claims 1 to 8, wherein the crystalline polyester is a hybrid crystalline polyester in which a crystalline polyester unit and an amorphous resin unit are chemically bonded. The toner according to claim 9 , wherein the hybrid crystalline polyester is a resin in which a crystalline polyester unit and an amorphous resin unit are bonded without using a nitrogen atom. The toner according to claim 9 , wherein the hybrid crystalline polyester is a resin in which a crystalline polyester unit and an amorphous vinyl resin unit are chemically bonded. The toner according to claim 1 , further satisfying a relationship represented by the following formula (7).
Formula (7): 65 <Tm <80

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