JP2020024320A - toner - Google Patents

Abstract

To provide toner excellent in low-temperature fixability without blocking the low-temperature fixability of a resin composing a core.SOLUTION: In toner containing toner particles of core shell structure, composed of: a core containing binding resin A and a coloring agent; and a shell, the binding resin A and the shell both contain crystalline polyester. The fluidity properties of the binding resin A and the shell are measured for 15 seconds, taken from casting of the sample to the start of the measurement, using a narrow tube type rheometer of constant load push-out system, in which the area of a pressure application surface, with respect to a sample, of a piston that applies pressure on the sample is 1.0 cm, and the diameter of a die hole through which the sample is pushed out is 0.5 mm. In this case, if a pressure of 1.0 MPa is applied to the sample at a constant temperature by the piston, and the binding resin A is tA[sec] and the shell is tS[sec] in terms of time taken for the displacement of the piston to be equal to 1.5 mm from the start of the application of the pressure, the following formulae (1) and (2) are satisfied: 200.0≤tA≤3000.0 (1); 1.0≤tS≤150.0 (2).SELECTED DRAWING: None

Description

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

In recent years, energy saving has been considered as a major technical issue in electrophotographic apparatuses, and significant reduction in the amount of heat applied to a fixing device is being studied. In particular, there is a growing need for so-called "low-temperature fixability" for toner, which enables fixing with lower energy.
In recent years, in order to improve the low-temperature fixability of a toner, a method of including a crystalline resin in a binder resin has been studied. Due to the regular arrangement of molecular chains, the crystalline resin hardly softens at a temperature lower than the melting point, and the crystal rapidly melts at a temperature higher than the melting point, resulting in a sharp decrease in viscosity. For this reason, it has attracted attention as a material having excellent sharp melt properties and exhibiting low-temperature fixability.
In addition, one of the crystalline resins, the block polymer containing a crystalline polyester portion and an amorphous portion is excellent in sharp melt properties, and can maintain elasticity at high temperatures, and thus has excellent fixability. Various studies have been made as materials.
Patent Document 1 proposes a toner containing a block polymer composed of a crystalline polyester part and an amorphous polyurethane part as a core, and a vinyl resin partially containing a crystalline polyester as a shell.
Patent Document 2 proposes a toner containing a crystalline vinyl resin as a shell. This toner is excellent in low-temperature fixability because both the core and the shell use a resin having high crystallinity.

JP 2012-042939 A JP 2014-032242 A

However, in the case of Patent Document 1, it is often observed that the resin constituting the shell impairs the low-temperature fixability of the resin constituting the core and lowers the low-temperature fixability of the toner. It is considered that the reason is that the melting rate of the shell is lower than that of the core because the resin constituting the shell has a comb structure.
Further, in Patent Document 2, it is observed that a fixed image of the obtained toner is very fragile and easily peels off from paper. This is probably because the crystalline vinyl resin used for the shell has low affinity with paper and the core resin, and low adhesion between the toner and the paper and between the toners.
From the above, further improvement has been demanded for realizing a toner having a shell which does not hinder the low-temperature fixability of the resin constituting the core and having excellent low-temperature fixability.
The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide a toner having excellent low-temperature fixability without impairing the low-temperature fixability of a resin constituting a core.

The present invention for solving the above problems is as follows.
A toner containing toner particles having a core-shell structure including a binder resin A, a core containing a colorant, and a shell,
Both the binder resin A and the shell contain crystalline polyester,
The time from the input of a sample to the start of measurement using a constant load extrusion type capillary rheometer with a piston pressurizing the sample with an area of 1.0 cm ^{2 for} the sample and a die hole diameter of 0.5 mm for extruding the sample. In the measurement of the flow characteristics of the binder resin A and the shell, where
When the sample is pressurized at a pressure of 1.0 MPa with a piston at 80 ° C. for the binder resin A and at 85 ° C. for the shell, from the start of pressurization until the displacement of the piston becomes 1.5 mm. When the time is defined as tA [second] for the binder resin A and tS [second] for the shell resin, the following formulas (1) and (2) are satisfied.
200.0 ≦ tA ≦ 3000.0 (1)
1.0 ≦ tS ≦ 150.0 (2)

  ADVANTAGE OF THE INVENTION According to this invention, the toner which is excellent in low-temperature fixability can be provided, without obstructing the low-temperature fixability of the resin which comprises a core.

FIG. 2 is a schematic view illustrating an example of a manufacturing apparatus of the toner of the present invention. FIG. 2 is a schematic view illustrating an example of a charge amount measuring device for the toner of the present invention.

  In a normal electrophotographic fixing process, the toner on the transfer material is fixed to the transfer material by being pressurized and heated. In the process, the time for heating the toner is as short as about 10 milliseconds. Therefore, in order to determine the fixing performance, it is important for the low-temperature fixing that the melting speed is high at a low temperature.

  Means for Solving the ProblemsThe present inventors have used a block polymer containing a crystalline polyester portion and an amorphous portion having an extremely high melting rate in a core, and have intensively studied the requirements for a shell that does not inhibit the low-temperature fixability of the block polymer. .

  As a result, it was found that when the shell contains the crystalline polyester, and more desirably, the block polymer containing the crystalline polyester portion and the organic polysiloxane portion is used for the shell, so that the inhibition to the low-temperature fixing is eliminated. .

  As a result of detailed examination, in order to make the melting rate faster than that of a block polymer containing a crystalline polyester part and an amorphous part, it is necessary to use a crystalline polyester used as a shell with a linear structure, It was found that it was effective to have a phase separation structure between the polyester part and the organic polysiloxane part. In any case, the structure having crystallinity can exist as a minute domain, and the control of the degree of crystallinity and the size of the domain is not a factor that increases the melting rate to an unprecedented level. I guess.

  The toner of the present invention is a toner containing toner particles having a core-shell structure composed of a core containing a binder resin, a colorant, and a shell, wherein both the binder resin A and the shell contain a crystalline polyester. I do. Since the crystalline polyester has an ester bond in addition to the sharp melt property, the crystalline polyester has a high affinity for paper, and the adhesion to a fixed image is improved. Further, since both the binder resin A and the shell have crystalline polyester, the adhesion between toners at the time of fixing is also improved.

The toner of the present invention is obtained by a constant load extrusion type capillary rheometer in which a piston pressurizing the sample has a pressing surface area of 1.0 cm ^{2 with} respect to the sample and a die hole diameter of 0.5 mm through which the sample is extruded. In the measurement of the flow characteristics of the binder resin A and the shell with the time from the start to the measurement being 15.0 seconds, the pressure was applied by a piston at 80 ° C. for the binder resin A and 85 ° C. for the shell. When the sample is pressurized at 1.0 MPa, the time from the start of pressurization until the displacement of the piston becomes 1.5 mm is tA [sec] for the binder resin A and tS [sec] for the shell. Where the following formulas (1) and (2) are satisfied.
200.0 ≦ tA ≦ 3000.0 (1)
1.0 ≦ tS ≦ 150.0 (2)

  tA represents the melting rate of the binder resin A at 80 ° C., and tS represents the melting rate of the shell at 85 ° C. 80 ° C. is close to the temperature applied to the toner during normal low temperature fixing. Further, since the shell exists on the toner surface, heat is applied more than the binder resin A at the time of fixing. Accordingly, by setting the melting rate under the condition that tS is higher than tA by 5 ° C. within the range, it is possible to eliminate fixing inhibition.

  When tA and tS are within the above ranges, the melting speed of the shell becomes higher than the melting speed of the binder resin A, and the low-temperature fixability of the binder resin A can be sufficiently exhibited without impairing the low-temperature fixability of the binder resin A. .

  When tA is smaller than 200.0, the melting rate of the binder resin A becomes too high, and in addition, since the resin contains a crystalline polyester having a high affinity for paper, penetration into the paper at the time of fixing increases. , The gross decreases. When tA is larger than 3000.0, the melting rate of the binder resin A is too low, so that the low-temperature fixability deteriorates. The more preferable range of tA is 500.0 or more and 2000.0 or less. If tS is smaller than 1.0, the wax will not ooze onto the toner surface at the time of fixing, and the offset resistance tends to decrease. However, it is difficult to make tS smaller than 1.0 in a normal configuration. If it is larger than 150.0, the melting of the binder resin A is hindered, and the low-temperature fixability deteriorates. The more preferable range of tS is 10.0 or more and 120.0 or less.

  The shell of the present invention will be described. The shell of the present invention is preferably formed uniformly and densely on the surface of the core containing the binder resin A and the colorant, but this is not limited as long as the configuration of the present invention is used.

  The resin used for the shell of the present invention is preferably of a linear type. Here, the linear type means that the polymer has no branch having a molecular weight of 100 or more from the main chain. By being a straight-chain type, entanglement of molecules during melting is less likely to occur, and the melting speed of the shell can be easily controlled within the range of the above formula (2). Conversely, when the polymer has a large number of branches, entanglement of the molecules tends to occur, and the melting rate tends to be low. For example, a polymer having a comb structure having a high molecular weight component further from the main chain to a side chain of the polymer tends to have a low melting rate.

  The shell of the present invention contains a crystalline polyester. It is preferable that the crystalline polyester uses an aliphatic diol having 2 to 20 carbon atoms and an aliphatic dicarboxylic acid having 2 to 20 carbon atoms as raw materials. Further, the aliphatic diol and the aliphatic dicarboxylic acid are preferably linear.

  Examples of the linear aliphatic diol suitably used in the present invention include the following, but are not limited thereto. In some cases, they can be used in combination. Ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonane Diol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eico Sundiol.

  Examples of the linear aliphatic dicarboxylic acid preferably used in the present invention include the following, but are not limited thereto. In some cases, they can be used in combination. Oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid. Or its lower alkyl ester or acid anhydride.

  Also, an aromatic carboxylic acid can be used as long as the crystallinity is not impaired. Examples of the aromatic dicarboxylic acid include the following compounds. Terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and 4,4'-biphenyldicarboxylic acid.

  Among these, terephthalic acid is preferable in that it is easily available and easily forms a polymer having a low melting point.

  The method for producing the crystalline polyester is not particularly limited, and the crystalline polyester can be produced by a general polyester polymerization method in which the diol monomer and the dicarboxylic acid monomer are reacted. For example, direct polycondensation and transesterification are used depending on the type of monomer.

  The production of the crystalline polyester is preferably carried out at a polymerization temperature of 180 ° C. or higher and 230 ° C. or lower, and if necessary, reducing the pressure in the reaction system and performing the reaction while removing water or alcohol generated during condensation. preferable. When the monomer is not dissolved or compatible at the reaction temperature, it is preferable to dissolve the monomer by adding a high boiling point solvent as a solubilizing agent. In the polycondensation reaction, the reaction is performed while distilling off the solubilizing aid. When a monomer having poor compatibility is present in the copolymerization reaction, it is preferable that the monomer having poor compatibility and the monomer or acid or alcohol to be polycondensed are condensed in advance, and then polycondensed together with the main component.

  Examples of the catalyst that can be used in the production of the crystalline polyester include the following. A titanium catalyst of titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide. Tin catalysts of dibutyltin dichloride, dibutyltin oxide and diphenyltin oxide.

  Further, the crystalline polyester also includes a crystalline polyester obtained by ring-opening polymerization of an aliphatic lactone. As the aliphatic lactone suitably used in the present invention, for example, δ-hexalanolactone, δ-octanolactone, ε-caprolactone, δ-dodecanolactone, α-methyl-γ-butyrolactone, β-methyl -Δ-valerolactone, ω-pentadecanolactone, glycolide, lactide and the like. Among these, the combination of ε-caprolactone and ω-pentadecanolactone facilitates adjustment of the melting point, and is preferably used.

  Examples of the initiator that can be used for the ring-opening polymerization include a linear aliphatic alcohol. Examples of the linear aliphatic monol include the following. Methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-decanol, lauryl alcohol, myristyl alcohol, cetanol, stearyl alcohol, behenyl alcohol. Among them, stearyl alcohol and behenyl alcohol are preferred from the viewpoint of easy control of molecular weight. As the straight-chain aliphatic diol, the straight-chain aliphatic diol usable for the above-mentioned crystalline polyester is used.

  The ring-opening polymerization is preferably performed at a polymerization temperature of 120 ° C. or higher and 200 ° C. or lower, and if necessary, the pressure in the reaction system is preferably reduced. It is also preferable to add a solvent having a high boiling point as a solubilizer.

  As a catalyst that can be used for the ring-opening polymerization, a catalyst that can be used in the production of the crystalline polyester can also be used.

  The melting point of the crystalline polyester is preferably from 45 ° C. to 120 ° C., and more preferably from 50 ° C. to 90 ° C. in consideration of melting at the fixing temperature.

  The shell of the present invention preferably contains a block polymer C containing two different types of crystalline polyester moieties. The block polymer C containing two different types of crystalline polyester sites has two melting points. It is considered that the presence of the block polymer C facilitates the miniaturization of domains having crystallinity, and facilitates controlling the melting rate of the shell within the range of the formula (2).

  As the crystalline polyester usable for the crystalline polyester portion of the block polymer C, the crystalline polyester usable for the shell described above is used.

  The melting point of the crystalline polyester portion of the block polymer C is preferably 50 ° C. or more and less than 70 ° C., and the other is 70 ° C. or more and 90 ° C. or less.

  Examples of the block polymer C include XY-type block polymers, XYX-type block polymers, XYXY... Type-type block polymers of a crystalline polyester portion (X) and a different type of crystalline polyester portion (Y). Can also be used. Further, an XYZ-type block polymer or an XYZ-type block polymer into which an amorphous portion (Z) is introduced can also be used. These can be designed to satisfy the above equation (2).

  The amorphous portion (Z) is not particularly limited as long as it is an amorphous resin, but amorphous polyester and amorphous polyurethane are preferably used.

  Hereinafter, the amorphous polyester will be described. Examples of monomers that can be used for producing the amorphous polyester include a conventionally known divalent or trivalent or higher carboxylic acid and a divalent or trivalent or higher alcohol. Specific examples of these monomers include the following.

  The following compounds can be mentioned as the divalent carboxylic acid. Dibasic acids such as succinic acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, malonic acid, dodecenylsuccinic acid, and their anhydrides or lower alkyl esters thereof; and maleic acid, fumaric acid, Aliphatic unsaturated dicarboxylic acids such as itaconic acid and citraconic acid.

  Further, examples of the trivalent or higher carboxylic acid include the following compounds. 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and anhydrides or lower alkyl esters thereof. These may be used alone or in combination of two or more.

  The following compounds can be mentioned as dihydric alcohols. Alkylene glycols (ethylene glycol, 1,2-propylene glycol and 1,3-propylene glycol); alkylene ether glycols (polyethylene glycol and polypropylene glycol); alicyclic diols (1,4-cyclohexanedimethanol); bisphenols (bisphenol A): Alkylene oxide (ethylene oxide and propylene oxide) adducts of alicyclic diols.

  The alkyl portion of the alkylene glycol and the alkylene ether glycol may be linear or branched. In the present invention, a branched alkylene glycol can also be preferably used.

  Further, examples of the trivalent or higher alcohol include the following compounds. Glycerin, trimethylolethane, trimethylolpropane and pentaerythritol. These may be used alone or in combination of two or more.

  For the purpose of adjusting the acid value and the hydroxyl value, monovalent acids such as acetic acid and benzoic acid, and monohydric alcohols such as cyclohexanol and benzyl alcohol can be used as necessary.

  The method for synthesizing the amorphous polyester is not particularly limited. For example, a transesterification method or a direct polycondensation method can be used alone or in combination.

  Next, the amorphous polyurethane will be described. Polyurethane is a reaction product of a diol and a substance containing a diisocyanate group, and a resin having various functions can be obtained by adjusting the diol and the diisocyanate.

  The following are mentioned as a diisocyanate component. Aromatic diisocyanate having 6 to 20 carbon atoms (excluding carbon in the NCO group, the same applies hereinafter), aliphatic diisocyanate having 2 to 18 carbon atoms, alicyclic diisocyanate having 4 to 15 carbon atoms, and these diisocyanates (Modified products containing a urethane group, carbodiimide group, allophanate group, urea group, buret group, uretdione group, uretoimine group, isocyanurate group or oxazolidone group; hereinafter also referred to as "modified diisocyanate"); A mixture of two or more of the above.

  The following are mentioned as an aromatic diisocyanate. m- and / or p-xylylene diisocyanate (XDI) and α, α, α ′, α′-tetramethylxylylene diisocyanate.

  The following are examples of the aliphatic diisocyanate. Ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI) and dodecamethylene diisocyanate.

  In addition, examples of the alicyclic diisocyanate include the following. Isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate, cyclohexylene diisocyanate, and methylcyclohexylene diisocyanate.

  Among these, preferred are aromatic diisocyanates having 6 to 15 carbon atoms, aliphatic diisocyanates having 4 to 12 carbon atoms, and alicyclic diisocyanates having 4 to 15 carbon atoms, and particularly preferred are XDI , IPDI and HDI.

  In addition to the diisocyanate component, a tri- or higher functional isocyanate compound can be used.

  As the diol component that can be used for the amorphous polyurethane, the same diol component as the dihydric alcohol that can be used for the above-described amorphous polyester can be used.

  The block polymer C in the present invention can be prepared by selecting from various methods in consideration of the reactivity of each terminal functional group.

  In the case of a block polymer having a crystalline polyester site (X) and a different type of crystalline polyester site (Y), it can be prepared by separately preparing each component and then bonding it with a binder as necessary. it can.

  In particular, when one polyester has a high acid value and the other polyester has a high hydroxyl value, the binding can be performed without using a binder. At this time, the reaction is preferably performed at around 200 ° C.

  When a binder is used, the following binders may be used. Polycarboxylic acids, polyhydric alcohols, polyhydric isocyanates, polyfunctional epoxies, polyhydric anhydrides. It can be synthesized by a dehydration reaction or an addition reaction using these binders. In particular, it is preferable to use a polyvalent isocyanate.

  When the block polymer C in the present invention is a block polymer having a crystalline polyester site (X) and a different type of crystalline polyester site (Y), and an amorphous site (Z), the block polymer C is different from the crystalline polyester site (X). Can be prepared in the same manner as in the case of the block polymer with the crystalline polyester moiety (Y). That is, the components can be prepared by separately preparing the components and then binding them with a binder as necessary. In particular, when the amorphous portion (Z) is amorphous polyurethane, it can be prepared by subjecting an alcohol terminal of the crystalline polyester to an isocyanate terminal of the amorphous polyurethane to a urethanization reaction. The synthesis can also be performed by mixing a crystalline polyester having an alcohol terminal, a diol and a diisocyanate constituting an amorphous polyurethane, and heating the mixture. In the early stage of the reaction in which the diol and diisocyanate concentrations are high, the diol and diisocyanate selectively react to form an amorphous polyurethane, and after the molecular weight increases to some extent, a urethanization reaction occurs between the isocyanate end of the polyurethane and the alcohol end of the crystalline polyester. , Block polymer C.

  In the block polymer C of the present invention, the terminal of the molecular chain may be modified with an acidic functional group. Examples of the acidic functional group include a carboxy group, a sulfone group, and a phosphate group. Among them, a carboxy group is preferably used from the viewpoint of chargeability.

  As an example of the modification of the acidic functional group to the block polymer C, a method of urethanizing a compound having an acidic functional group and an alcohol and a block polymer C precursor having an alcohol at a terminal with isocyanate is used.

  The block polymer C of the present invention is preferably of a linear type. By being a linear type, the entanglement of the polymer during melting is easily reduced, and the melting rate is easily increased.

  The block polymer C of the present invention has a number-average molecular weight (Mn) of 4,000 or more and 15,000 or less and a weight-average molecular weight (Mw) of 6,000 or more and 25,000 or less in THF-soluble GPC measurement. Is preferred.

  The shell of the present invention preferably has an organic polysiloxane structure represented by the following formula (3).

（式（３）中、Ｒ¹及びＲ²は、それぞれ独立に、炭素数１以上３以下のアルキル基を表す。ｎは２以上１５０以下である。）

(In the formula (3), R ¹ and R ² each independently represent an alkyl group having 1 to 3 carbon atoms. N is 2 to 150.)

  The organic polysiloxane structure has low interfacial tension and excellent environmental stability. Therefore, by using the shell having the organic polysiloxane structure, environmental stability of the toner, in particular, a decrease in the charge amount in a high-temperature and high-humidity environment is easily suppressed. In addition, since the organic polysiloxane has a glass transition temperature (Tg) lower than room temperature, by having the organic polysiloxane structure, the melting rate of the shell can be easily increased, and the formula (2) can be easily satisfied. .

  In the toner of the present invention, the ratio of the organic polysiloxane structure in the shell is preferably 10.0% by mass or more and 30.0% by mass or less with respect to the shell. Within this range, the charge retention of the toner in a high-temperature, high-humidity environment is easily improved.

  The shell of the present invention preferably contains a block polymer D containing a crystalline polyester moiety and the aforementioned organic polysiloxane structure. By using the block polymer D, the organic polysiloxane structure can be easily uniformly present in the shell, and excellent environmental stability can be easily exhibited. In addition, the crystalline polyester portion easily forms minute domains, and the melting rate is easily increased.

  As the crystalline polyester moiety usable for the block polymer D, the crystalline polyester moiety usable for the shell can be similarly used.

  In the block polymer D, a UV type block polymer, a UVU type block polymer, a VUV type block polymer, a UVUV... Type block of a crystalline polyester site (U) and a site (V) containing an organic polysiloxane structure Any form can be used, including polymers. In addition, a UVZ type block polymer, a UZV type block polymer, or the like into which the amorphous portion (Z) is introduced can also be used. These can be designed to satisfy the above equation (2). Preferably, it is a UV type block polymer.

  The block polymer D of the present invention can be prepared by selecting from various methods in consideration of the reactivity of each terminal functional group, as in the method of preparing the block polymer C.

  In the block polymer D of the present invention, the ratio of the organic polysiloxane structure is preferably 20.0% by mass to 80.0% by mass with respect to the block polymer D.

  The block polymer D of the present invention is preferably of a linear type. By being a linear type, the entanglement of the polymer during melting is easily reduced, and the melting rate is easily increased.

  The block polymer D of the present invention has a number-average molecular weight (Mn) of 4,000 or more and 15,000 or less and a weight-average molecular weight (Mw) of 6,000 or more and 25,000 or less in THF-soluble GPC measurement. Is preferred.

  In the toner of the present invention, the ratio of the total crystalline polyester in the shell is preferably 50.0% by mass or more and 85.0% by mass or less with respect to the shell. By being in this range, it is easy to achieve the expression (2). Here, when a block polymer containing an amorphous portion is used for the shell, the amorphous portion in the block polymer is not regarded as a crystalline polyester. For example, when the block polymer D is used for the shell, the site containing the organic polysiloxane structure in the block polymer D is not regarded as the crystalline polyester, and only the crystalline polyester site is regarded as the crystalline polyester. .

  In the toner of the present invention, the content of the shell is preferably from 3.0% by mass to 15.0% by mass, and more preferably from 3.0% by mass to 12.0% by mass with respect to the toner particles. More preferably, there is. Within this range, the fixability of the binder resin is less likely to be impaired, and the environmental stability under high temperature and high humidity is easily maintained.

  The binder resin A of the present invention will be described. The binder resin A of the present invention contains a crystalline polyester. As the crystalline polyester usable for the binder resin A, the crystalline polyester usable for the shell can be used similarly.

  In the toner of the present invention, it is preferable that the binder resin A contains a block polymer B containing a crystalline polyester portion and an amorphous portion. By containing the block polymer B, the formula (1) can be easily achieved.

  The amorphous portion that can be used for the block polymer B is not particularly limited, but an amorphous polyester or an amorphous polyurethane as the amorphous portion (Z) that can be used for the block polymer C is preferable. Used. In particular, it is more preferable to contain an amorphous polyurethane component. By containing the amorphous polyurethane component, the high temperature elasticity of the block polymer B can be easily maintained.

  The ratio of the crystalline polyester site in the block polymer B is preferably from 50.0% by mass to 90.0% by mass with respect to the block polymer B.

  Further, the toner may contain an amorphous resin in addition to the binder resin A. As the amorphous resin, in addition to the amorphous polyester and the amorphous polyurethane as the amorphous portion (Z) described above, an amorphous vinyl resin can also be used.

  The monomers usable for the amorphous vinyl resin are listed below, but are not limited thereto.

  Aliphatic vinyl hydrocarbons: alkenes such as ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, and other α-olefins; alkadienes such as butadiene, isoprene, 1,4- Pentadiene, 1,6-hexadiene and 1,7-octadiene.

  Alicyclic vinyl hydrocarbons: mono- or di-cycloalkenes and alkadienes such as cyclohexene, cyclopentadiene, vinylcyclohexene, ethylidene bicycloheptene; terpenes such as pinene, limonene, indene.

  Aromatic vinyl hydrocarbon: Styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and / or alkenyl) substituted products, for example, α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butyl Styrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, crotylbenzene, divinylbenzene, divinyltoluene, divinylxylene, trivinylbenzene; and vinylnaphthalene.

  Carboxyl group-containing vinyl monomers and metal salts thereof: unsaturated monocarboxylic acids having 3 to 30 carbon atoms, unsaturated dicarboxylic acids and anhydrides thereof and monoalkyl (1 to 27 carbon atoms) esters thereof, for example, acrylic acid, Methacrylic acid, maleic acid, maleic anhydride, monoalkyl maleate, fumaric acid, monoalkyl fumarate, crotonic acid, itaconic acid, monoalkyl itaconate, glycol monoether itaconate, citraconic acid, monoalkyl citraconic acid Esters and carboxyl group-containing vinyl monomers of cinnamic acid.

  Vinyl esters, for example, vinyl acetate, vinyl butyrate, vinyl propionate, vinyl butyrate, diallyl phthalate, diallyl adipate, isopropenyl acetate, vinyl methacrylate, methyl 4-vinyl benzoate, cyclohexyl methacrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, vinyl Methoxy acetate, vinyl benzoate, ethyl α-ethoxy acrylate, alkyl acrylate and alkyl methacrylate having an alkyl group having 1 to 11 carbon atoms (linear or branched) (methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, Propyl methacrylate, butyl acrylate, butyl methacrylate, 2-d Lehexyl acrylate, 2-ethylhexyl methacrylate, dialkyl fumarate (dialkyl fumarate) (two alkyl groups are linear or branched or alicyclic groups having 2 to 8 carbon atoms), dialkyl Maleate (maleic acid dialkyl ester) (the two alkyl groups are straight-chain, branched or alicyclic groups having 2 to 8 carbon atoms), polyallyloxyalkanes (diallyloxyethane , Triaryloxyethane, tetraallyloxyethane, tetraallyloxypropane, tetraallyloxybutane, tetramethallyloxyethane), vinyl monomers having a polyalkylene glycol chain (polyethylene glycol (molecular weight 300) monoacrylate, polyethylene glycol ( Molecular weight 300) monomethacrylate, Polypropylene glycol (molecular weight 500) monoacrylate, polypropylene glycol (molecular weight 500) monomethacrylate, methyl alcohol ethylene oxide (ethylene oxide is abbreviated as EO hereinafter), 10 mol adduct acrylate, methyl alcohol ethylene oxide (ethylene oxide is abbreviated as EO) Methacrylate, 10 mol adduct methacrylate, 30 mol adduct of lauryl alcohol EO, acrylate 30 mol adduct of lauryl alcohol EO), polyacrylates and polymethacrylates (polyacrylates and polymethacrylates of polyhydric alcohols).

  Especially, it is preferable to copolymerize styrene and methacrylic acid.

  In the toner of the present invention, the ratio of the binder resin A in the binder resin is preferably 50.0% by mass or more, more preferably 80.0% by mass or more based on the binder resin. preferable. Further, it is particularly preferable to use only the binder resin A as the binder resin.

  The toner of the present invention may have a number-average molecular weight (Mn) of 4,000 or more and 30,000 or less and a weight-average molecular weight (Mw) of 15,000 or more and 60,000 or less in THF-soluble polymer GPC measurement. preferable. A more preferred range of Mn is 6,000 or more and 20,000 or less, and a more preferred range of Mw is 20,000 or more and 50,000 or less. Further, Mw / Mn is preferably 6 or less.

  The toner particles used in the toner of the present invention may preferably contain a wax. The wax is not particularly limited, and examples thereof include the following.

  Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymer, microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax A wax mainly composed of a fatty acid ester such as an aliphatic hydrocarbon ester wax; and a partially or totally deoxidized fatty acid ester such as a deoxidized carnauba wax; a fatty acid such as a behenic acid monoglyceride; A partially esterified product of a polyhydric alcohol; a methyl ester compound having a hydroxyl group obtained by hydrogenating a vegetable oil or fat.

  Particularly preferred waxes used in the toner of the present invention are aliphatic hydrocarbon waxes and ester waxes. Further, the ester wax used in the present invention is preferably a trifunctional or higher functional ester wax, more preferably a tetrafunctional or higher functional ester wax, particularly preferably a hexafunctional or higher functional ester wax.

  The trifunctional or higher functional ester wax is obtained by, for example, condensation of a trifunctional or higher functional acid and a long-chain linear saturated alcohol, or synthesis of a trifunctional or higher functional alcohol and a long-chain linear saturated fatty acid.

  Examples of the trifunctional or higher functional alcohol that can be used in the wax include, but are not limited to, the following. In some cases, they can be used in combination. Glycerin, trimethylolpropane, erythritol, pentaerythritol, sorbitol. Further, as these condensates, so-called polyglycerin such as diglycerin condensed with glycerin, triglycerin, tetraglycerin, hexaglycerin and decaglycerin, ditrimethylolpropane condensed with trimethylolpropane, tristrimethylolpropane and pentaerythritol Examples thereof include condensed dipentaerythritol and trispentaerythritol. Among these, a structure having a branched structure is preferable, pentaerthritol or dipentaerythritol is more preferable, and dipentaerythritol is particularly preferable.

Long, straight-chain saturated fatty acid usable in the present invention are represented by the general formula _{C n H 2n + 1 COOH,} n is having 5 or more 28 or less is preferably used.

  For example, the following may be mentioned, but the present invention is not limited thereto. In some cases, they can be used in combination. Caproic acid, caprylic acid, octylic acid, nonylic acid, decanoic acid, dodecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Myristic acid, palmitic acid, stearic acid and behenic acid are preferred from the viewpoint of the melting point of the wax.

  Examples of the trifunctional or higher functional acid usable in the present invention include, but are not limited to, the following. In some cases, they can be used in combination. Trimellitic acid, butanetetracarboxylic acid.

The long-chain straight-chain saturated alcohol usable in the present invention is represented by C _n H _{2n + 1} OH, and those having n of 5 or more and 28 or less are preferably used.

  For example, the following may be mentioned, but the present invention is not limited thereto. In some cases, they can be used in combination. Examples include caprylic alcohol, lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, and behenyl alcohol. From the viewpoint of the melting point of the wax, myristyl alcohol, palmityl alcohol, stearyl alcohol, and behenyl alcohol are preferred.

  In the toner of the present invention, the content of the wax in the toner particles is preferably from 1.0% by mass to 20.0% by mass, and more preferably from 2.0% by mass to 15.0% by mass. When the content is 1.0% by mass or more, the releasability of the toner is exhibited, and even when the temperature of the fixing body becomes low, the winding of the transfer paper hardly occurs. When the content is 20.0% by mass or less, exposure of the wax to the toner surface hardly occurs, and heat resistance storage stability is not impaired.

  The wax preferably has a maximum endothermic peak at 60 ° C. or more and 120 ° C. or less as measured by a differential scanning calorimeter (DSC). More preferably, it is 60 ° C or more and 90 ° C or less. When the maximum endothermic peak is 60 ° C. or higher, exposure of the wax to the toner surface is less likely to occur, and heat resistance storage stability is high. On the other hand, when the maximum endothermic peak is 120 ° C. or less, the wax is appropriately melted at the time of fixing, and the low-temperature fixing property and the offset resistance are maintained.

  In the toner of the present invention, the toner may contain a colorant. Colorants preferably used in the present invention include organic pigments, organic dyes, inorganic pigments, carbon black as a black colorant, and magnetic particles, and other colorants conventionally used in toners can be used. .

  Examples of the colorant for yellow include the following. Condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, allylamide compounds. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, 180 are preferably used.

  Examples of the magenta colorant include the following. Condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254 are preferably used.

  Examples of the cyan colorant include the following. Copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 are preferably used.

  The colorant used in the toner of the present invention is selected from the viewpoints of hue angle, saturation, lightness, light fastness, OHP transparency, and dispersibility in the toner.

  The colorant is preferably used by adding 1.0 to 20.0 parts by mass to 100.0 parts by mass of the binder resin. When magnetic particles are used as the colorant, the amount added is preferably from 40.0 parts by mass to 150.0 parts by mass with respect to 100.0 parts by mass of the binder resin.

  In the toner of the present invention, a charge control agent may be contained in the toner particles as needed. Further, it may be externally added to the toner particles. By blending the charge control agent, the charge characteristics can be stabilized and the optimal amount of triboelectric charge can be controlled according to the development system.

  As the charge control agent, known charge control agents can be used. In particular, a charge control agent having a high charging speed and capable of stably maintaining a constant charge amount is preferable.

  Examples of the charge control agent that controls the toner to be negatively charged include the following. Organic metal compounds and chelate compounds are effective, and examples thereof include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. The following are examples of devices that control the toner to be positively charged. Nigrosine, quaternary ammonium salts, metal salts of higher fatty acids, diorganotin borates, guanidine compounds, imidazole compounds.

  A preferable compounding amount of the charge control agent is 0.01 to 20.0 parts by mass, more preferably 0.5 to 10.0 parts by mass, based on 100.0 parts by mass of the toner particles. .

  In the toner of the present invention, any method may be used for producing the toner particles. However, since the toner particles have a core-shell structure, various methods for forming a core-shell structure are preferable. The formation of the shell phase may be performed simultaneously with the step of forming the core, or may be performed after the formation of the core. From the viewpoint of simplicity, it is preferable to simultaneously perform the core manufacturing step and the shell phase forming step.

  The method for forming the shell phase is not limited at all. For example, when the shell phase is provided after the core is formed, there is a method of dispersing the resin fine particles forming the core and the shell phase in an aqueous medium, and then aggregating and adsorbing the resin fine particles on the core surface. . In the case where the shell phase is formed simultaneously with the step of forming the core, the binder resin forming the core is dissolved in an organic medium in a dispersion medium in which resin fine particles forming the shell phase are dispersed. Disperse the resin composition. Thereafter, a dissolution suspension method in which the organic medium is removed to obtain toner particles is preferably used.

  It is particularly preferable that the toner particles used in the toner of the present invention are produced in a non-aqueous medium. Therefore, in the production of the toner particles of the present invention, a solution suspension method using carbon dioxide in a high-pressure state as a dispersion medium is particularly suitable.

  That is, in the toner of the present invention, the toner particles are preferably toner particles manufactured by the following manufacturing method. First, a resin composition is prepared by dissolving or dispersing a binder resin, a colorant and, if necessary, a wax in a medium containing an organic solvent. Next, in the presence of the shell fine particles, the resin composition is dispersed in a dispersion medium containing carbon dioxide in a high-pressure state as a main component. Then, toner particles are manufactured by removing the organic solvent from the obtained dispersion.

  Here, the high-pressure carbon dioxide is preferably carbon dioxide having a pressure of 1.5 MPa or more. Further, liquid or carbon dioxide in a supercritical state may be used alone as a dispersion medium, and may contain an organic solvent as another component. In this case, it is preferable that carbon dioxide in a high pressure state and the organic solvent form a homogeneous phase.

  Hereinafter, a method for producing toner particles using a dispersion medium containing carbon dioxide in a high-pressure state, which is suitable for obtaining the toner particles used in the toner of the present invention, will be described by way of example.

  First, in the resin solution preparation step, a coloring agent, and if necessary, a wax and other additives are added to an organic solvent capable of dissolving the binder resin, and a homogenizer, a ball mill, a colloid mill, an ultrasonic disperser Is uniformly dissolved or dispersed by a dispersing machine such as

  Next, in the granulation step, the resin solution thus obtained and carbon dioxide in a high pressure state are mixed to form droplets of the resin solution.

  At this time, it is necessary to disperse the dispersant in carbon dioxide in a high pressure state as a dispersion medium. Examples of the dispersant include resin fine particles for forming a shell phase, and other components may be mixed as a dispersant. For example, any of an inorganic fine particle dispersant, an organic fine particle dispersant, and a mixture thereof may be used, and two or more kinds may be used in combination depending on the purpose.

  Further, a dispersion stabilizer in a liquid state may be added. Examples of the dispersion stabilizer include compounds having a high affinity for carbon dioxide, such as the organic polysiloxane structure and the compound containing fluorine, and various surfactants such as a nonionic surfactant, an anionic surfactant, and a cationic surfactant. Can be These dispersion stabilizers are discharged out of the system together with carbon dioxide in a solvent removal step described later. Therefore, the amount remaining in the toner particles after the preparation of the toner particles is extremely small.

  In the method for producing the toner particles used in the toner of the present invention, any method may be used for dispersing the dispersant in a dispersion medium containing carbon dioxide in a high pressure state. As a specific example, there is a method in which a dispersion medium containing the dispersant and carbon dioxide in a high-pressure state is charged in a container and directly dispersed by stirring or ultrasonic irradiation. Further, there is a method in which a dispersion in which the dispersant is dispersed in an organic solvent is introduced into a container charged with a dispersion medium containing carbon dioxide in a high-pressure state using a high-pressure pump.

  In the present invention, any method may be used for dispersing the resin composition in a dispersion medium containing carbon dioxide in a high-pressure state. As a specific example, there is a method in which the resin composition is introduced into a container containing a dispersion medium containing carbon dioxide in a high-pressure state in which the dispersant is dispersed using a high-pressure pump. Further, a dispersion medium containing carbon dioxide in a high pressure state in which the dispersant is dispersed may be introduced into a container charged with the resin composition.

  In the present invention, the dispersion medium containing carbon dioxide in a high-pressure state is preferably a single phase. When granulation is performed by dispersing the resin composition in carbon dioxide in a high-pressure state, a part of the organic solvent in the liquid droplets moves into the dispersion. At this time, it is not preferable that the phase of carbon dioxide and the phase of the organic solvent exist in a separated state because the stability of droplets is impaired. Therefore, it is preferable that the amount of the resin composition with respect to the temperature and pressure of the dispersion medium and the carbon dioxide in a high-pressure state be adjusted within a range in which the carbon dioxide and the organic solvent can form a uniform phase.

  With regard to the temperature and pressure of the dispersion medium, attention must also be paid to the granulation properties (easiness of forming droplets) and the solubility of the components in the resin composition in the dispersion medium. For example, the binder resin and wax in the resin composition may be dissolved in the dispersion medium depending on the temperature and pressure conditions. Usually, the lower the temperature and the pressure, the more the solubility of the above components in the dispersion medium is suppressed, but the formed droplets are liable to aggregate and coalesce, and the granulation property is reduced. On the other hand, the higher the temperature and pressure, the better the granulation properties, but the tendency is that the components are more easily dissolved in the dispersion medium. Therefore, in the production of the toner particles of the present invention, it is preferable that the temperature of the dispersion medium is in a temperature range of 10 ° C. to 50 ° C.

  Further, the pressure in the container forming the dispersion medium is preferably 1.5 MPa or more and 20.0 MPa or less, more preferably 2.0 MPa or more and 15.0 MPa or less. In addition, when the component other than carbon dioxide is contained in the dispersion medium, the pressure in the present invention indicates the total pressure thereof.

  After the completion of the granulation in this way, in the solvent removal step, the organic solvent remaining in the droplets is removed via a carbon dioxide dispersion medium in a high pressure state. Specifically, carbon dioxide in a high-pressure state is further mixed with the dispersion medium in which the droplets are dispersed, and the remaining organic solvent is extracted into a carbon dioxide phase. It is performed by replacing with carbon dioxide in a state.

  The mixing of the dispersion medium and the carbon dioxide in the high pressure state may be performed by adding carbon dioxide at a higher pressure to the dispersion medium, or by adding the dispersion medium to carbon dioxide at a lower pressure. Is also good.

  As a method of replacing carbon dioxide containing an organic solvent with carbon dioxide in a higher pressure state, a method of flowing carbon dioxide in a high pressure state while keeping the pressure in a container constant may be mentioned. At this time, the toner particles are formed while being captured by a filter.

  When the replacement with the carbon dioxide in the high-pressure state is not sufficient and the organic solvent remains in the dispersion medium, when the pressure in the container is reduced to collect the obtained toner particles, the solvent is dissolved in the dispersion medium. The organic solvent may condense and the toner particles may be redissolved. Further, there may be a problem that toner particles are united with each other. Therefore, it is necessary to perform the replacement with carbon dioxide in the high-pressure state until the organic solvent is completely removed. The amount of carbon dioxide in the high-pressure state to be circulated is preferably 1 to 100 times, more preferably 1 to 50 times, more preferably 1 to 30 times the volume of the dispersion medium. is there.

  When the container is depressurized and the toner particles are taken out from the dispersion containing the carbon dioxide in a high pressure state in which the toner particles are dispersed, the temperature may be reduced to normal temperature and normal pressure at once, but the pressure-controlled containers are independently multi-staged. The pressure may be reduced stepwise by providing. The decompression speed is preferably set within a range where the toner particles do not foam.

  The organic solvent and carbon dioxide used in the present invention can be recycled.

  In the toner of the present invention, it is preferable to add inorganic fine particles to the toner particles as a fluidity improver. Examples of the inorganic fine particles to be added to the toner particles include fine particles such as silica fine particles, titanium oxide fine particles, alumina fine particles, and double oxide fine particles thereof. Among the inorganic fine particles, silica fine particles and titanium oxide fine particles are preferable.

Examples of the silica fine particles include dry silica or fumed silica produced by vapor phase oxidation of a silicon halide, and wet silica produced from water glass. Among them, dry silica having less silanol groups on the surface and inside the silica fine particles and having less Na ₂ O and SO ₃ ²⁻ is more preferable. Further, the fumed silica may be composite fine particles of silica and another metal oxide produced by using a metal halide compound such as aluminum chloride or titanium chloride together with a silicon halide compound in the production process.

  It is preferable that the inorganic fine particles are externally added to the toner particles in order to improve the fluidity of the toner and to make the charge of the toner uniform. Further, by performing the hydrophobic treatment on the inorganic fine particles, the charge amount of the toner can be adjusted, the environmental stability can be improved, and the characteristics can be improved under a high humidity environment. It is more preferable to use When the inorganic fine particles added to the toner absorb moisture, the charge amount of the toner tends to decrease, and developability and transferability tend to decrease.

  Examples of the treating agent for the hydrophobic treatment of the inorganic fine particles include unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organosilicon compounds, and organotitanium. Compounds. These treating agents may be used alone or in combination.

  Among them, inorganic fine particles treated with silicone oil are preferred. More preferably, at the same time as or after the hydrophobic treatment of the inorganic fine particles with the coupling agent, the hydrophobic treated inorganic fine particles treated with silicone oil treated with silicone oil maintain the charge amount of the toner particles high even in a high humidity environment. However, it is preferable from the viewpoint of reducing the selective developability.

  The amount of the inorganic fine particles to be added is preferably 0.1 parts by mass or more and 4.0 parts by mass or less based on 100.0 parts by mass of the toner particles. More preferably, it is not less than 0.2 parts by mass and not more than 3.5 parts by mass.

  An example of a method for measuring various physical properties of the toner and the toner material of the present invention is described below.

<Measurement method of tA and tS in constant load extrusion type capillary rheometer>
The measurement of tA and tS is performed according to a manual attached to the apparatus using a constant load extrusion type capillary rheometer “Flow tester CFT-500D” (manufactured by Shimadzu Corporation). In this device, while applying a constant load with the piston from the top of the measurement sample filled in the cylinder, the inside of the cylinder is heated to melt the measurement sample, and the melted measurement sample is pushed out from the die at the bottom of the cylinder. A flow curve showing the relationship between the amount of displacement (displacement) and time can be obtained.

As a measurement sample, about 0.22 g of the sample (the binder resin A and the resin forming the shell) was used in a 25 ° C. environment using a tablet molding compressor (for example, NT-100H, manufactured by NPA System Co., Ltd.). Compression molding at about 12 MPa for about 60 seconds to form a column having a bottom area of 1.0 cm ² (diameter of about 11.3 mm) and a thickness of about 2.2 mm.

The measurement conditions of CFT-500D when measuring tA and tS are as follows.
Test mode: constant temperature method Measurement temperature: 80 ° C for tA, 85 ° C for tS
Piston bottom area (area of measurement pressurized surface): 1.0 cm ²
Test load (piston load): 5.0 MPa
Preheating time: 0 seconds Die hole diameter: 0.5 mm
Die length: 1.0mm
Measurement start: The measurement sample is put into a cylinder, and measurement (pressurization) is started 15 seconds after the piston is set.

  From the flow curve produced by the measurement, the time [sec] at which the displacement reaches 1.5 mm is read, and these are defined as tA and tS.

  In addition, when the measurement sample is a plurality of resins, for example, when the shell is a mixture of the block polymer C and the block polymer D, the sample is melt-mixed in advance, and the sample after freeze-pulverization is used.

<Measurement method of melting point>
The melting point of the crystalline material used in the toner of the present invention is measured using DSC Q1000 (manufactured by TA Instruments) under the following conditions.
Heating rate: 10 ° C / min
Measurement start temperature: 20 ° C
Measurement end temperature: 180 ° C

  The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat quantity correction uses the heat of fusion of indium.

  Specifically, about 5 mg of a sample is precisely weighed, placed in an aluminum pan, and subjected to differential scanning calorimetry. An empty silver pan is used as a reference.

  The peak temperature of the maximum endothermic peak in the first heating process is defined as the melting point.

  Note that the maximum endothermic peak is the peak at which the amount of endotherm becomes maximum when there are a plurality of peaks.

<Method for Mn and Mw Measurement>
The molecular weight (Mn, Mw) of the THF-soluble component of the toner and the material used in the present invention is measured by gel permeation chromatography (GPC) as follows.

First, the sample is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. Then, the obtained solution is filtered through a solvent-resistant membrane filter “Maisho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven columns of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml

  When calculating the molecular weight of the sample, a standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-20, 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation).

<Method for Measuring Particle Size of Resin Fine Particle for Shell, Wax Fine Particle, and Colorant Fine Particle>
In the present invention, the particle diameter of each fine particle is measured using a Microtrac particle size distribution analyzer HRA (X-100) (manufactured by Nikkiso Co., Ltd.) in the range of 0.001 μm to 10 μm, and the volume average particle diameter (μm Or nm). Note that acetone or hexane is selected as the diluting organic solvent.

  Hereinafter, the present invention will be described specifically with reference to Production Examples and Examples, but this does not limit the present invention in any way.

<Synthesis of crystalline polyester 1>
The following raw materials were charged into a heated and dried two-necked flask while introducing nitrogen.
· 81.0 parts by mass of 1,6-hexanediol · 131.0 parts by mass of sebacic acid · 0.1 parts by mass of dibutyltin oxide After the inside of the system was purged with nitrogen by a reduced pressure operation, the mixture was stirred at 180 ° C for 6 hours. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure while continuing the stirring, and further maintained for 2 hours. When the mixture became viscous, the mixture was air-cooled to stop the reaction, thereby synthesizing crystalline polyester 1. Table 1 shows the physical properties of the crystalline polyester 1.

<Synthesis of crystalline polyesters 2 and 3>
In the synthesis of crystalline polyester 1, crystalline polyesters 2 and 3 were synthesized in the same manner except that the amounts of raw materials used were changed as shown in Table 1. Table 1 shows the physical properties of crystalline polyesters 2 and 3.

<Synthesis of crystalline polyester 4>
The following raw materials were charged into a heated and dried two-necked flask while introducing nitrogen.
• 6.0 parts by mass of ε-caprolactone • 25.3 parts by mass of ω-pentadecanolactone • 3.2 parts by mass of stearyl alcohol • 0.1 part by mass of dibutyltin oxide For 3 hours. Thereafter, the mixture was air-cooled and the reaction was stopped, whereby a crystalline polyester 4 was synthesized. Table 2 shows the physical properties of the crystalline polyester 4.

<Synthesis of crystalline polyesters 5 to 7>
In the synthesis of crystalline polyester 4, crystalline polyesters 4 to 7 were synthesized in the same manner except that the amounts of raw materials used were changed as shown in Table 2. Table 2 shows the physical properties of the crystalline polyesters 4 to 7.

<Synthesis of binder resin A1>
-240.0 parts by mass of crystalline polyester 1-20.8 parts by mass of xylylene diisocyanate (XDI)-39.2 parts by mass of cyclohexane dimethanol (CHDM)-300.0 parts by mass of tetrahydrofuran (THF) A stirrer and a thermometer were used. The above reactor was charged into a equipped reaction vessel while purging with nitrogen. The mixture was heated to 50 ° C. and subjected to a urethanization reaction for 15 hours. The solvent, THF, was distilled off to obtain a binder resin A1. Table 3 shows the physical properties of the binder resin A1.

<Synthesis of binder resins A2 to A9>
In the synthesis of binder resin A1, binder resins A2 to A9 were synthesized in the same manner except that the amounts of the raw materials used were changed as shown in Table 3. Table 3 shows the physical properties of binder resins A2 to A9.

<Synthesis of amorphous resin 1>
The following raw materials were charged into a heated and dried two-necked flask while introducing nitrogen.
・ Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane
30.0 parts by mass polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane
33.0 parts by mass, 21.0 parts by mass of terephthalic acid, 15.0 parts by mass of dodecenylsuccinic acid, 0.1 part by mass of dibutyltin oxide After the inside of the system was replaced with nitrogen by a reduced pressure operation, the mixture was stirred at 215 ° C. for 5 hours. . Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure while continuing the stirring, and further maintained for 2 hours. When it became a viscous state, it was air-cooled to stop the reaction, thereby synthesizing the amorphous resin 1 as an amorphous polyester. Mn of the amorphous resin 1 was 5,200, Mw was 23,000, and Tg was 55 ° C.

<Synthesis of binder resin A10>
・ 240.0 parts by mass of crystalline polyester 1 ・ 60.0 parts by mass of amorphous resin 1 ・ 5.0 parts by mass of xylylene diisocyanate (XDI) ・ 300.0 parts by mass of tetrahydrofuran (THF) equipped with a stirrer and a thermometer The above reactor was charged into a reaction vessel while replacing with nitrogen. The mixture was heated to 50 ° C. and subjected to a urethanization reaction for 15 hours. The solvent, THF, was distilled off to obtain a binder resin A10. The Mn of the binder resin A10 was 15,820, the Mw was 43,280, and the melting point was 63 ° C.

<Preparation of binder resin solutions A1 to A10>
500.0 parts by mass of acetone and 500.0 parts by mass of binder resins A1 to A10 were put into a beaker equipped with a stirrer, and stirring was continued at 40 ° C. until the solution was completely dissolved. Was prepared.

<Synthesis of resin 1 for shell>
-54.4 parts by mass of crystalline polyester 1-51.9 parts by mass of crystalline polyester 4-2.0 parts by mass of xylylene diisocyanate (XDI)-400.0 parts by mass of toluene In a reaction vessel equipped with a stirrer and a thermometer The above was charged while purging with nitrogen. The mixture was heated to 80 ° C. and subjected to a urethanization reaction for 5 hours to obtain a block polymer composed of crystalline polyester 1 and crystalline polyester 4.

3.4 parts by mass of 1,4-dihydroxybenzoic acid4.1 parts by mass of xylylene diisocyanate (XDI) The above materials were further added and reacted at 80 ° C. for 2 hours. The solvent, toluene, was distilled off to obtain Shell Resin 1. Table 5 shows the physical properties of Resin 1 for shell.

<Synthesis of Shell Resins 2 to 4>
In the synthesis of the shell resin 1, shell resins 2 to 4 were synthesized in the same manner as above except that the kind of raw materials to be used and the charged amount were changed as shown in Table 4. Table 5 shows the physical properties of Shell Resins 2 to 4.

<Synthesis of resin 5 for shell>
-48.2 parts by mass of crystalline polyester 4-45.5 parts by mass of X-22-170DX (single-terminal carbinol-modified silicone, Mn4600: manufactured by Shin-Etsu Silicone)-1.8 parts by mass of xylylene diisocyanate (XDI)-Toluene 400 0.0 parts by mass The above components were charged into a reaction vessel equipped with a stirrer and a thermometer while purging with nitrogen. The mixture was heated to 80 ° C. and subjected to a urethanization reaction for 5 hours. The toluene as a solvent was distilled off to obtain a shell resin 5 comprising a crystalline polyester 4 and an organic polysiloxane moiety (R ¹ and R ² in the formula (3) are CH ₃ ). Table 5 shows the physical properties of the shell resin 5.

<Synthesis of resin 6 for shell>
In the synthesis of the shell resin 1, a shell resin 6 was synthesized in the same manner except that the amounts of the raw materials used were changed as shown in Table 6. Table 5 shows the physical properties of the shell resin 6.

<Preparation of resin fine particle dispersion 1 for shell>
The following materials were charged into a sample bottle and dissolved to obtain a resin solution.
-Shell resin 1 15.0 parts by mass-Shell resin 5 15.0 parts by mass-Toluene 150.0 parts by mass

The following materials were charged into the flask to obtain an aqueous phase.
-570.0 parts by mass of ion-exchanged water-3.0 parts by mass of sodium dodecyl sulfate While stirring the aqueous phase, the resin solution was dropped into the aqueous phase. Thereafter, the mixture was treated with an ultrasonic homogenizer (UH-300, manufactured by SMT Corporation) for 5 minutes to form submicrometer-sized droplets of the resin solution in an aqueous phase. Thereafter, toluene contained in the droplets was removed by an evaporator to obtain an aqueous dispersion of the resin particles 1 for a shell. Ultrafiltration was performed to remove excess sodium dodecyl sulfate in the aqueous dispersion, and moisture was removed by freeze-drying to obtain resin fine particles 1 for shell.

  20.0 parts by mass of the resin particles for shell 1 was added to 80.0 parts by mass of acetone, and the mixture was treated with an ultrasonic homogenizer for 5 minutes to prepare a resin particle dispersion 1 for shell. Table 7 shows the physical properties of the resin particle dispersion 1 for shell.

<Preparation of resin fine particle dispersions 2 to 8 for shell>
Shell fine resin particle dispersions 2 to 8 were prepared in the same manner as in preparation of shell fine resin particle dispersion 1, except that the kinds and amounts of various materials were changed as shown in Table 7. Table 7 shows the physical properties of the resin fine particle dispersions 2 to 8 for shells.

<Preparation of resin fine particle dispersion liquid 9 for shell>
870.0 parts by mass of normal hexane was charged into a two-necked flask equipped with a dropping funnel and dried by heating. In a separate beaker, 42.0 parts by mass of normal hexane, 52.0 parts by mass of behenyl acrylate (an acrylate of an alcohol having a straight-chain alkyl group having 22 carbon atoms), and 0.3 parts by mass of azobismethoxydimethylvaleronitrile were charged. The mixture was stirred and mixed at 20 ° C. to prepare a monomer solution, which was introduced into a dropping funnel. After purging the reaction vessel with nitrogen, the monomer solution was added dropwise at 40 ° C. over 1 hour in a sealed state. Stirring was continued for 3 hours from the end of the dropping, and a mixture of 0.3 parts by mass of azobismethoxydimethylvaleronitrile and 42.0 parts by mass of normal hexane was dropped again, followed by stirring at 40 ° C. for 3 hours. Thereafter, the mixture was cooled to room temperature to obtain a resin fine particle dispersion 9 for shell having a volume average particle diameter of 250 nm, a solid content of 20.0% by mass, Mn of 12,340 and Mw of 28,600.

<Synthesis of vinyl-modified polyester monomer>
-100.0 parts by mass of crystalline polyester 2-100.0 parts by mass of tetrahydrofuran (THF) The above materials were charged into a reaction vessel equipped with a stirrer and a thermometer while replacing with nitrogen, and dissolved at 40 ° C.

  6.2 parts by mass of 2-isocyanatoethyl methacrylate (Karenz MOI manufactured by Showa Denko KK) was added dropwise and reacted at 40 ° C. for 2 hours to obtain a vinyl-modified polyester monomer solution. Subsequently, THF was removed under reduced pressure at 40 ° C. for 5 hours by a rotary evaporator to obtain a vinyl-modified polyester monomer.

<Preparation of resin fine particle dispersion liquid 10 for shell>
-15.0 parts by mass of vinyl-modified organic polysiloxane (X-22-2475: n = 3, manufactured by Shin-Etsu Chemical Co., Ltd.)
51.0 parts by mass of a vinyl-modified polyester monomer 26.5 parts by mass of styrene (St) 7.5 parts by mass of methacrylic acid (MAA) 0.3 parts by mass of azobismethoxydimethylvaleronitrile 30 parts by mass of normal hexane 0 parts by mass The above was charged into a beaker, stirred and mixed at 20 ° C. to prepare a monomer solution, and introduced into a dropping funnel that had been heated and dried in advance. Separately, 300.0 parts by mass of normal hexane was charged into a heated and dried two-necked flask. After purging with nitrogen, a dropping funnel was attached, and the monomer solution was added dropwise at 40 ° C. for 1 hour in a sealed state. Stirring was continued for 3 hours from the end of the dropwise addition, and a mixture of 0.3 parts by mass of azobismethoxydimethylvaleronitrile and 20.0 parts by mass of normal hexane was again added dropwise, followed by stirring at 40 ° C. for 3 hours. Thereafter, by cooling to room temperature, a resin fine particle dispersion 10 for shell having a volume average particle diameter of 180 nm, a solid content of 20.0% by mass, an Mn of 32,500 and an Mw of 78,910 was obtained.

<Preparation of resin fine particle dispersion liquid 11 for shell>
428 parts by mass of 2-hydroxyethyl methacrylate was dropped into 572.0 parts by mass of TDI (tolylene diisocyanate) and reacted at 55 ° C. for 4 hours to obtain a vinyl monomer intermediate.

  480.0 parts by weight of HS2H-500S (1,6-hexanediol / sebacic acid-based crystalline polyester resin, manufactured by Toyokuni Oil Co., Ltd.) is dissolved in 500.0 parts of THF at 70 ° C., and 20.0 parts of a vinyl monomer intermediate is dissolved. The mixture was dropped and reacted at 70 ° C. for 4 hours to obtain a vinyl monomer solution.

  A reaction vessel was charged with 560.0 parts by mass of a vinyl monomer solution, and 316.0 parts by mass of THF, 120.0 parts by mass of maleic acid, 2,2′-azobis (2,4-dimethylvaleronitrile) were placed in another glass beaker. ) 4.0 parts by mass was charged, stirred and mixed at 20 ° C to prepare a monomer solution, and charged into a dropping funnel. After replacing the gas phase of the reaction vessel with nitrogen, the monomer solution is added dropwise at 70 ° C. over a period of time in a sealed state, and the mixture is aged at 70 ° C. for 2 hours from the end of the dropwise addition. Removal under reduced pressure for 3 hours gave a vinyl resin. This resin had a melting point of 65 ° C., Mn of 7,500, and Mw of 35,820.

  After mixing 800.0 parts by mass of normal hexane and 200.0 parts by mass of the vinyl resin, pulverization was carried out using a zirconia bead having a particle diameter of 0.3 mm in a bead mill (Dynomill Multilab: manufactured by Shinmaru Enterprises). A resin fine particle dispersion 11 for shell having a volume average particle diameter of 290 nm and a solid content of 20.0% by mass was obtained. .

<Preparation of colorant dispersion>
・ C. I. Pigment Blue 15: 3 100.0 parts by mass, acetone 150.0 parts by mass, glass beads (10.0 mm, 300.0 parts by mass) The above-mentioned materials are put into a heat-resistant glass container, and dispersed for 5 hours using a paint shaker (manufactured by Toyo Seiki). Then, the glass beads were removed with a nylon mesh to obtain a colorant dispersion having a volume average particle size of 200 nm and a solid content of 40.0% by mass.

<Preparation of wax dispersion>
16.0 parts by mass of dipentaerythritol palmitate wax Wax dispersant (50.0 parts by mass of styrene, 25.0 parts by mass of n-butyl acrylate, 10.0 parts by mass of acrylonitrile in the presence of 15.0 parts by mass of polyethylene) A copolymer having a peak molecular weight of 8,500 obtained by graft copolymerization of the above-mentioned parts) 8.0 parts by mass and 76.0 parts by mass of acetone The above was charged into a glass beaker (manufactured by IWAKI glass) equipped with stirring blades, and the system was heated to 50 parts by mass. The wax was dissolved in acetone by heating to ° C.

  Next, the inside of the system was gradually cooled with gentle stirring under the condition of 50 rpm, and cooled to 25 ° C. over 3 hours to obtain a milky white liquid.

  This solution was put into a heat-resistant container together with 20 parts by mass of 1 mm glass beads, and dispersed for 3 hours with a paint shaker. Then, the glass beads were removed with a nylon mesh, the volume average particle diameter was 270 nm, and the solid content was A wax dispersion of 24% by mass was obtained.

[Example 1]
(Production of toner particles 1)
In a beaker,
-200.0 parts by mass of binder resin solution A1-50.0 parts by mass of resin fine particle dispersion 1 for shell-20.0 parts by mass of wax dispersion-12.0 parts by mass of colorant dispersion were added, and 40.0 parts by mass was added. After the temperature was adjusted to ℃, the resin composition 1 was obtained by stirring for 1 minute at 3000 rpm using a disper (manufactured by Tokushu Kika Co., Ltd.).

  In the apparatus shown in FIG. 1, the resin composition 1 is charged into a granulation tank t1 whose internal temperature has been previously adjusted to 35.0 ° C., the valve V1 and the pressure adjustment valve V2 are closed, and the inside of the granulation tank t1 is rotated at a rotational speed. While stirring at 300 rpm, the temperature of Resin Composition 1 was adjusted to 35.0 ° C. The valve V1 was opened, carbon dioxide (purity: 99.99%) was introduced into the granulation tank t1 from the cylinder B1, and the valve V1 was closed when the internal pressure reached 2.0 MPa.

  The mass of the introduced carbon dioxide was 270.0 parts by mass as measured with a mass flow meter.

  After confirming that the temperature in the container was 35.0 ° C., the mixture was stirred at a rotation speed of 1000 rpm for 10 minutes to perform granulation, thereby preparing a dispersion.

  Next, the rotation speed was reduced to 300 rpm, and the inside of the vessel was cooled to 25.0 ° C. at a rate of 0.5 ° C./min.

  Next, the valve V1 was opened, and carbon dioxide was introduced into the granulation tank t1 from the cylinder B1 using the pump P1. At this time, the pressure adjustment valve V2 was set at 8.0 MPa, and carbon dioxide was further allowed to flow while the internal pressure of the granulation tank t1 was maintained at 8.0 MPa. By this operation, carbon dioxide containing the organic solvent (mainly acetone) extracted from the granulated droplets was discharged to the solvent recovery tank t2, and the organic solvent and carbon dioxide were separated.

  One hour later, the pump P1 is stopped, the valve V1 is closed, the pressure regulating valve V2 is gradually opened, and the internal pressure of the granulation tank t1 is reduced to the atmospheric pressure, thereby collecting the toner particles 1 captured by the filter. did.

(Preparation Step of Toner 1)
1.8 parts by mass of hydrophobic silica fine powder treated with hexamethyldisilazane (number-average primary particle diameter: 7 nm), 0.15 parts by mass of rutile-type titanium oxide fine powder with respect to 100 parts by mass of toner particles 1 (Number average primary particle diameter: 30 nm) was dry-mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) for 5 minutes to obtain Toner 1 of the present invention. Table 8 shows the physical properties of the obtained toner.

<Evaluation method of toner>
<1> Low-temperature fixability Using a commercially available Canon printer LBP5300, low-temperature fixability was evaluated. The LBP 5300 employs one-component contact development, and regulates the amount of toner on the developer carrier by a toner regulating member. The evaluation cartridge used was one in which the toner contained in a commercially available cartridge was extracted, the inside of the cartridge was cleaned with an air blow, and the obtained toner was filled. The cartridge was allowed to stand in a normal temperature and normal humidity environment (23 ° C./60%) for 24 hours, and then mounted on the LBP5300 cyan station, and a dummy cartridge was mounted on the other parts. Next, an unfixed toner image (toner application amount per unit area: 0.4 mg / cm ² , upper margin: 30 mm, lower margin: 15 mm, left and right margin: 10 mm) was placed on plain paper for copying machines (81.4 g / m ² ). Formed.

  The fixing device of a commercially available Canon printer LBP5900 was modified so that the fixing temperature could be manually set, the rotation speed of the fixing device was changed to 300 mm / s, and the pressure in the nip was changed to 98 kPa. Using the modified fixing device, a fixed image at each temperature of the unfixed image was obtained while increasing the fixing temperature in a range of 95 ° C. to 150 ° C. by 5 ° C. in a normal temperature and normal humidity environment.

  A polyester tape was attached to the image area of the obtained fixed image, and rubbing was performed five times while applying a load of 4.9 kPa from above. Thereafter, the tape was peeled off, and the temperature at which the reduction rate (%) of the image density before and after the tape was peeled was less than 5% was defined as the fixing start temperature, which was used as an index of the low-temperature fixability. The image density was measured by a color reflection densitometer X-Rite 404A (manufactured by X-Rite).

[Evaluation criteria]
A: Fixing start temperature is less than 100 ° C B: Fixing start temperature is 100 ° C or more and less than 110 ° C C: Fixing start temperature is 110 ° C or more and less than 120 ° C D: Fixing start temperature is 120 ° C or more

<2> Fixing Inhibition In a sample bottle, 100.0 parts by mass of binder resin A1, 4.8 parts by mass of dipentaerythritol palmitate ester wax, and C.I. I. Pigment Blue 15: 3 was added in an amount of 4.8 parts by mass. The above was heated on a hot plate at 140 ° C. to melt the binder resin A1 and dipentaerythritol palmitate wax, and then mixed well. After that, the particles pulverized by the freeze pulverizer were used as the toner particles 1 ′ having the binder resin A1 as a core and no shell.

  1.8 parts by mass of hydrophobic silica fine powder treated with hexamethyldisilazane (number-average primary particle diameter: 7 nm), 0.15 part by mass of rutile-type titanium oxide fine powder with respect to 100 parts by mass of the toner particles 1 ' Parts (number average primary particle size: 30 nm) was dry-mixed for 5 minutes using a Henschel mixer (Mitsui Mining Co., Ltd.) to obtain toner 1 ′.

  The toner 1 'was evaluated for <1> to measure the fixing start temperature of the toner 1', and the difference from the fixing start temperature of the toner 1 was used as an index of the fixing inhibition by the shell. . Table 9 shows the evaluation results.

[Evaluation criteria]
A: Difference in fixing start temperature is 0 ° C.
B: Difference in fixing start temperature is more than 0 ° C. and 5 ° C. or less C: Difference in fixing start temperature is more than 5 ° C. and 10 ° C. or less D: Difference in fixing start temperature is more than 10 ° C.

<Permeation into paper>
For the image fixed at a temperature 30 ° C. higher than the fixing start temperature measured in the test of <1>, an incident angle of light of 75 was measured using a gloss meter PG-3D (manufactured by Nippon Denshoku Industries). The average value of three arbitrary points on each image under the condition of ° was defined as a gloss value, which was used as an index of permeation into paper. Table 9 shows the evaluation results.

[Evaluation criteria]
A: Gloss value is 25 or more B: Gloss value is 20 or more and less than 25 C: Gloss value is 15 or more and less than 20 D: Gloss value is less than 15

<4> Cold offset resistance For the same fixed image as in <1>, the cold offset was visually evaluated, and the cold offset resistance was evaluated. Table 9 shows the evaluation results.

[Evaluation criteria]
A: The temperature at which a cold offset occurs with respect to the fixing start temperature is 5 ° C. or less. B: The temperature at which the cold offset occurs with respect to the fixing start temperature is greater than 5 ° C. and 10 ° C. or less. C: The cold offset occurs with respect to the fixing start temperature. The temperature is higher than 10 ° C. and equal to or lower than 15 ° C. D: The temperature at which the cold offset occurs relative to the fixing start temperature is higher than 15 ° C.

<5> Environmental Stability The difference in charge amount between a low temperature and low humidity (LL) environment and a high temperature and high humidity (HH) environment was evaluated by the following method.

  1.0 g and 19.0 g of a toner and a predetermined carrier (standard carrier of the Imaging Society of Japan: spherical carrier N-01 having a ferrite core surface-treated) are respectively placed in a plastic bottle with a lid, at a temperature of 15 ° C. and a relative humidity of 10% In an LL environment and an HH environment with a temperature of 32.0 ° C. and a relative humidity of 85% for 5 days.

The lid of the plastic bottle containing the carrier and the toner is closed, and shaken at a speed of four reciprocations per second for 1 minute with a shaking machine (YS-LD, manufactured by Yayoi Co., Ltd.), and the toner and the carrier are formed. Charge the developer. Next, the amount of triboelectric charge is measured by the device for measuring triboelectric charge shown in FIG. In FIG. 2, 0.5 g or more and 1.5 g or less of the developer are placed in a metal measurement container 2 having a screen 3 having an opening of 20 μm at the bottom, and a metal lid 4 is provided. At this time, the mass of the entire measurement container 2 is precisely weighed and is defined as W1 (g). Next, in the suction device 1 (at least the portion in contact with the measurement container 2 is at least an insulator), the pressure of the vacuum gauge 5 is adjusted to 2.5 kPa by adjusting the air volume control valve 6 by suctioning from the suction port 7. In this state, suction is performed for 2 minutes to remove the toner by suction. The potential of the electrometer 9 at this time is set to V (V). Here, 8 is a capacitor whose capacity is C (mF). In addition, the mass of the entire measurement container after the suction is precisely weighed and set as W2 (g). The triboelectric charge Q (mC / kg) of this sample is calculated as in the following equation.
Amount of triboelectric charge of sample Q (mC / kg) = C × V / (W1−W2)

  When the triboelectric charge of the sample immediately after shaking in the LL environment was Ql (mC / kg) and the triboelectric charge in the HH environment was Qh (mC / kg), Qh / Ql was used as an index of environmental stability.

  Table 9 shows the evaluation results.

[Evaluation criteria]
A: Qh / Ql is 0.85 or more B: Qh / Ql is 0.80 or more and less than 0.85 C: Qh / Ql is 0.75 or more and less than 0.80 D: Qh / Ql is less than 0.75

[Examples 2 to 15]
Toner particles 2 to 15 were obtained in the same manner as in Example 1, except that the type of resin used was changed as shown in Table 8. Further, in the same manner as in Example 1, toners 2 to 15 were obtained. Table 8 shows the physical properties of the obtained toner. Table 9 shows the results of the same evaluation as in Example 1. The evaluation of (2) was performed using the binder resin A used in each example.

[Comparative Examples 1 to 6]
Comparative toner particles 1 to 6 were obtained in the same manner as in Example 1 except that the type of resin used was changed as shown in Table 8. Further, comparative toners 1 to 6 were obtained in the same manner as in Example 1. Table 8 shows the physical properties of the obtained comparative toner. Table 9 shows the results of the same evaluation as in Example 1. The evaluation of (2) was performed using the binder resin A used in each comparative example.

  t1: granulation tank, t2: solvent recovery tank, B1: cylinder, P1 pump, V1: valve, V2: pressure regulating valve

Claims (10)

A toner containing toner particles having a core-shell structure comprising a binder resin A, a core containing a colorant, and a shell,
Both the binder resin A and the shell contain crystalline polyester,
The time from the input of the sample to the start of measurement by a constant load extrusion type capillary rheometer in which the area of the pressing surface of the piston for pressing the sample against the sample is 1.0 cm ² and the diameter of the die hole through which the sample is extruded is 0.5 mm. In the measurement of the flow characteristics of the binder resin A and the shell with a time of 15 seconds, the sample was applied at a pressure of 1.0 MPa with a piston at 80 ° C. for the binder resin A and 85 ° C. for the shell. At the time of pressurization, when the time from the start of pressurization until the displacement of the piston becomes 1.5 mm is tA [sec] for the binder resin A and tS [sec] for the shell, the following formula (1) ) And (2).
200.0 ≦ tA ≦ 3000.0 (1)
1.0 ≦ tS ≦ 150.0 (2) The toner according to claim 1, wherein the shell has an organic polysiloxane structure represented by the following formula (3).

(In the formula (3), R ¹ and R ² each independently represent an alkyl group having 1 to 3 carbon atoms. N is 2 to 150.)   The toner according to claim 2, wherein the shell contains a block polymer C containing two different types of crystalline polyester sites and a block polymer D containing a crystalline polyester site and the organic polysiloxane site.   4. The toner according to claim 2, wherein a ratio of the organic polysiloxane structure in the shell is 10.0% by mass or more and 30.0% by mass or less with respect to the shell.   5. The toner according to claim 1, wherein a ratio of the total crystalline polyester in the shell is 50.0% by mass or more and 85.0% by mass or less with respect to the shell.   The toner according to claim 1, wherein the binder resin A contains a block polymer B containing a crystalline polyester part and an amorphous part.   The toner according to claim 6, wherein a ratio of the crystalline polyester site in the block polymer B is 50.0% by mass or more and 90.0% by mass or less with respect to the block polymer B.   The toner according to claim 6, wherein the amorphous portion in the block polymer B contains a polyurethane component.   The binder resin A contains a block polymer B containing a crystalline polyester part and an amorphous part, and the shell contains a block polymer D containing a crystalline polyester part and an organic polysiloxane part. Item 10. The toner according to any one of Items 1 to 8.   The toner according to claim 9, wherein the shell contains, in addition to the block polymer D, a block polymer C containing two different types of crystalline polyester moieties.

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