JP4758855B2 - Toner for electrophotography - Google Patents

Description

  The present invention relates to a binder resin for an electrophotographic toner used as a binder resin for a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, and the like, and the binder resin. The present invention relates to a toner for electrophotography.

In the electrophotographic field, a toner that satisfies the demand for higher speed and higher image quality is desired. On the other hand, by using a tin (II) compound having no Sn-C bond as a catalyst or using a silicon compound having a quaternary ammonium salt structure as a carrier coating agent, the rising property of charging can be improved. Techniques for improving and reducing background fogging and toner scattering are known (see Patent Documents 1 and 2).
JP 2003-231744 A JP 2006-38915 A

  However, conventional toners are insufficient for the recent demand for higher image quality. In other words, although the start-up property of charging can be secured as the speed increases, the image density necessary for high image quality, that is, the charge level is insufficient, and further development of a toner capable of supplying a high image density is desired. The

  An object of the present invention is to provide a binder resin for an electrophotographic toner that has a good charge amount level that provides a high image density with excellent charge rising property, and an electrophotographic toner containing the binder resin. is there.

The present invention
[1] Binder resin for electrophotographic toner containing a condensation polymerization resin obtained by condensation polymerization of raw material monomers in the presence of a tin (II) compound having no Sn-C bond and a sulfonic acid group-containing compound And [2] The present invention relates to an electrophotographic toner comprising the electrophotographic toner binder resin according to [1].

  The binder resin for electrophotographic toner of the present invention is excellent in charge rising property and has a good charge amount level that provides a high image density, and the electrophotographic toner containing such a binder resin provides a high-quality image. There is an excellent effect of being able to.

  The binder resin for an electrophotographic toner of the present invention is obtained by compressing a raw material monomer containing an alcohol component and a carboxylic acid component in the presence of a tin (II) compound having no Sn—C bond and a sulfonic acid group-containing compound. It has one feature in that it contains a condensation polymerization resin obtained by polymerization, and has the effect of being able to have a good charge amount level that is excellent in charge rise and that can realize a high image density. . Although the details of the reason why the charge characteristics such as the charge rising property and the charge amount level are excellent due to the condensation polymerization resin are unclear, the combined use of the tin (II) compound and the sulfonic acid group-containing compound increases the reaction rate, It is speculated that this may be due to the fact that a resin with a low history can be obtained and that the tin (II) compound exists in a stable state due to the presence of the sulfonic acid group-containing compound, and the charge is easily retained. .

  Examples of the condensation polymerization resin contained in the binder resin of the present invention include polyester, polyester / polyamide, polyamide, and the like. Among these, polyester is preferable from the viewpoint of durability and chargeability.

  As the polyester raw material monomer, an alcohol component and a carboxylic acid component are used.

  As alcohol components, 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, 1,4-butenediol, 1,2-propanediol, 1,3-butanediol, neopentyl glycol, 2-butyl-2-ethyl-1,3 -Aliphatic diols such as propanediol; polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, etc. Formula (I):

(In the formula, RO is an alkylene oxide, R is an alkylene group having 2 or 3 carbon atoms, x and y are positive numbers indicating the average number of moles added of alkylene oxide, and the sum of x and y is 1-16. ,
(Preferably 1-8, more preferably 1.5-5)
And aromatic diols such as alkylene oxide adducts of bisphenol A represented by the formula: trihydric or higher polyhydric alcohols such as glycerin and pentaerythritol.

  Examples of carboxylic acid components include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, etc. An aliphatic dicarboxylic acid such as cyclohexanedicarboxylic acid; an aromatic dicarboxylic acid such as phthalic acid, isophthalic acid or terephthalic acid; a trivalent or higher polyvalent carboxylic acid such as trimellitic acid or pyrrolemetic acid; and These acid anhydrides, alkyl (C1-3) esters and the like can be mentioned. Such acids, anhydrides of these acids, and alkyl esters of these acids are collectively referred to herein as carboxylic acid compounds.

  In the present invention, polyester includes not only polyester but also polyester modified to such an extent that its properties are not substantially impaired. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. Polyester.

  As the tin (II) compound having no Sn—C bond in the present invention, a tin (II) compound having an Sn—O bond, Sn—X (X represents a halogen atom) from the standpoint of charge rising property. ) A tin (II) compound having a bond is preferable, and a tin (II) compound having a Sn-O bond is more preferable.

Examples of tin (II) compounds having a Sn-O bond include tin (II) oxalate, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, tin (II) distearate, diolein Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms, such as tin (II) oxide and tin (II) di-2-ethylhexanoate; dioctyloxy tin (II), dilauroxy tin (II), distearoxy tin Dialkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms such as (II) and dioleoxytin (II); tin oxide (II); tin (II) sulfate, Sn—X (X is a halogen atom) Examples of the compound having a bond) include tin (II) chloride and tin (II) halides such as tin (II) bromide, among these, from the standpoint of charge rising effect and catalytic ability, ^(R 1 COO) ₂ Sn (wherein ^{R 1} represents an alkyl or alkenyl group having 5 to 19 carbon atoms) fatty acid and tin represented by ^{(II), (R 2 O} ) 2 Sn ( wherein ² dialkoxy tin (II) and tin oxide represented by SnO represented by an alkyl group or alkenyl group having 6 to 20 carbon atoms) (II) is preferably represented by (R ¹ COO) ₂ Sn Fatty acid tin (II) and tin oxide (II) are more preferable, and tin (II) dioctanoate, tin (II) distearate, tin (II) di-2-ethylhexanoate and tin (II) oxide are more preferable.

  The abundance of the tin (II) compound having no Sn—C bond is preferably 0.01 to 2.0 parts by weight with respect to 100 parts by weight of the total amount of raw material monomers of the polycondensation resin, from the standpoint of charge rise. 0.1-1.5 weight part is more preferable, 0.1-1.0 weight part is further more preferable, 0.1-0.8 weight part is further more preferable.

  Examples of the sulfonic acid group-containing compound in the present invention include aromatic sulfonic acid group-containing compounds, aliphatic sulfonic acid group-containing compounds, and the like. Among these, dispersibility in a resin, phase with polyester, and the like. An aromatic sulfonic acid group-containing compound is preferred from the viewpoint of solubility and charging characteristics.

  Examples of the aromatic sulfonic acid group-containing compound include p-toluenesulfonic acid, isotoluenesulfonic acid, metatoluenesulfonic acid, benzenesulfonic acid, p-xylene-2-sulfonic acid, naphthalene-1-sulfonic acid, naphthalene-2- Sulfonic acid, aminobenzenesulfonic acid, 2-aminotoluene-5-sulfonic acid, 8-amino-2-naphthalenesulfonic acid, 4-biphenylsulfonic acid, benzene-1,3-sulfonic acid, para-toluenesulfonic acid-2 butynyl , P-toluenesulfonic acid-3butynyl, p-toluenesulfonic acid-2chloroethyl, p-toluenesulfonic acid cyclohexyl, 2,5-dimethylbenzenesulfonic acid, ethyl benzenesulfonate, ethyl p-toluenesulfonate, bis-p-toluenesulfone Ethylene glycol, isobutyl p-toluenesulfonate, methyl benzenesulfonate, 1, Examples include 3,6-naphthalene trisulfonic acid, 1-naphthol-2-sulfonic acid, and salts (sodium salt, potassium salt and the like), hydrates, and methyl ester compounds of these compounds. Among the aromatic compounds, the substituent of the benzene ring is preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, and further preferably 1 to 4 carbon atoms from the viewpoint of chargeability.

  Aliphatic sulfonic acid group-containing compounds include ethanesulfonic acid, 1,2-ethanedisulfonic acid, hydroxyamine-O-sulfonic acid, methanesulfonic acid, ethyl methanesulfonate, trifluoromethanesulfonic acid, 1-butanesulfonic acid 1-decanesulfonic acid, 1-heptanesulfonic acid, 1-hexanesulfonic acid, 3-hydroxypropanesulfonic acid, 1-nonanesulfonic acid, 1-octanesulfonic acid, 1-pentanesulfonic acid, 1,3-propanedisulfone Examples include acids, 1-dodecanesulfonic acid, 1-hexadecanesulfonic acid, 1-propanesulfonic acid, vinylsulfonic acid and salts and hydrates thereof.

  The amount of the sulfonic acid group-containing compound is preferably from 0.001 to 1.0 part by weight, more preferably from 0.005 to 0.5 part by weight, based on 100 parts by weight of the total amount of raw material monomers of the condensation polymerization resin, from the viewpoint of increasing the saturated charge amount. 0.005-0.3 weight part is further more preferable.

  In addition, the weight ratio of the sulfonic acid group-containing compound and the tin (II) compound having no Sn—C bond [the sulfonic acid group-containing compound / the tin (II) compound having no Sn—C bond] is saturated. From the viewpoint of charge amount and reaction activity, 0.0005 to 10 is preferable, and from the viewpoint of saturation charge amount and reaction activity, 0.001 to 10 is more preferable, 0.005 to 1 is further preferable, and 0.01 to 0.5 is particularly preferable.

  In the polycondensation reaction in the present invention, an esterification catalyst other than a tin (II) compound having no Sn—C bond can be used as long as the effects of the present invention are not impaired. Examples of esterification catalysts other than tin (II) compounds having no Sn-C bond include dibutyltin oxide, titanium compounds, etc., and the total amount thereof is 100 parts by weight of the total amount of raw material monomers for the condensation polymerization resin. Is preferably 0.01 to 2.0 parts by weight, more preferably 0.05 to 1.0 parts by weight.

  The polycondensation of the alcohol component and the carboxylic acid component is carried out in the presence of a tin (II) compound having no Sn—C bond and a sulfonic acid group-containing compound, for example, at 180 to 250 ° C. in an inert gas atmosphere. Can be done at temperature.

  The tin (II) compound having no Sn-C bond and the sulfonic acid group-containing compound are present from the beginning of the polycondensation reaction even if they are added to the reaction system in the middle of the polycondensation reaction of raw material monomers such as alcohol components. Both compounds may be added simultaneously or separately, but from the viewpoint of catalytic activity, the sulfonic acid group-containing compound is tin (II) having no Sn—C bond. ) It is preferable to add at the same time as the compound or after the addition, and it is more preferable to add the sulfonic acid group-containing compound after the addition of the tin (II) compound having no Sn-C bond.

  The softening point of the condensation polymerization resin obtained in the presence of the tin (II) compound having no Sn-C bond and the sulfonic acid group-containing compound is preferably 90 to 160 ° C, and the glass transition point is 50 to 70. ° C is preferred.

  The content of the condensation polymerization resin in the binder resin of the present invention is preferably 50% by weight or more, and more preferably 70% by weight or more in the binder resin of the present invention.

  Examples of the binder resin other than the condensation polymerization resin include vinyl resins such as styrene-acrylic resins, epoxy resins, polycarbonates, polyurethanes, and the like. A composite resin having two or more kinds of resin components including the condensation polymerization resin component may be used.

  The composite resin has a condensation polymerization resin component and an addition polymerization resin component, and is preferably a resin obtained using a condensation polymerization resin raw material monomer and an addition polymerization resin raw material monomer.

  The polycondensation resin component includes the polycondensation resin, and polyester is preferable, and the addition polymerization resin component is preferably a vinyl resin.

  Examples of the raw material monomer for the polyester include the same components as mentioned above.

  As a raw material monomer for the vinyl resin, at least styrene is preferably used. The content of styrene is preferably 30 to 95% by weight, more preferably 60 to 90% by weight in the raw material monomer of the addition polymerization resin, from the viewpoint of the storage stability of the toner.

  As raw material monomers for addition polymerization resins other than styrene, styrene derivatives such as α-methylstyrene; ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; acetic acid Vinyl esters such as vinyl and vinyl propionate; alkyl (1 to 18 carbon atoms) esters of (meth) acrylic acid, esters of ethylenic monocarboxylic acids such as dimethylaminoethyl (meth) acrylate; vinyl methyl ether, etc. Vinyl ethers; vinylidene halides such as vinylidene chloride; and vinyl resin monomers such as N-vinyl compounds such as N-vinylpyrrolidone. Among these, ease of control of the polymerization reaction and safety From the standpoint of safety, alkyl ester of ethylenic monocarboxylic acid copolymerizable with styrene Preferably, (meth) alkyl acrylate (having 1 to 18 carbon atoms) ester is more preferred.

  The content of the alkyl ester of ethylenic monocarboxylic acid is preferably 5 to 70% by weight, more preferably 10 to 40% by weight, in the raw material monomer of the addition polymerization resin.

  Furthermore, the total content of alkyl esters of styrene and ethylenic monocarboxylic acid is preferably 70% by weight or more, more preferably 80% by weight or more, and still more preferably 90% by weight or more in the raw material monomer of the addition polymerization resin.

  The addition polymerization reaction can be carried out by a conventional method, for example, in the presence of a polymerization initiator, a crosslinking agent or the like, in an organic solvent or in the absence of a solvent, but the temperature condition is preferably 110 to 200 ° C., 140 to 170 ° C. Is more preferable.

  The weight ratio of the raw material monomer of the condensation polymerization resin and the raw material monomer of the addition polymerization resin used as the raw material monomer of the composite resin (the raw material monomer of the condensation polymerization resin / the raw material monomer of the addition polymerization resin) is the condensation polymerization resin component. From the viewpoint of forming a continuous phase, 55/45 to 95/5 is preferable, 60/40 to 95/5 is more preferable, and 70/30 to 90/10 is more preferable.

  In the present invention, as a raw material monomer for a composite resin, a hybrid obtained by using a compound that can further react with either a raw material monomer for a condensation polymerization resin or a raw material monomer for an addition polymerization resin (hereinafter referred to as a bireactive monomer) A resin is preferred. Therefore, in the present invention, the condensation polymerization reaction and the addition polymerization reaction are preferably performed in the presence of a bireactive monomer, whereby the condensation polymerization resin component and the addition polymerization resin component are partially partially reactive. A resin in which the addition polymerization resin component is finely and uniformly dispersed in the condensation polymerization resin component can be obtained by bonding via monomers.

  Both reactive monomers have at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, an epoxy group, a primary amino group and a secondary amino group in the molecule, preferably a hydroxyl group and / or carboxyl. It is preferably a compound having a group, more preferably a carboxyl group and an ethylenically unsaturated bond. Specific examples of the both reactive monomers include, for example, acrylic acid, methacrylic acid, fumaric acid, maleic acid and the like, and these hydroxyalkyl (1 to 3 carbon atoms) esters may be used. In view of the above, acrylic acid, methacrylic acid and fumaric acid are preferable.

  In the present invention, among both reactive monomers, a monomer having two or more functional groups (polycarboxylic acid or the like) and a derivative thereof are monomers having a single functional group (monocarboxylic acid or the like) as a raw material monomer for the condensation polymerization resin. ) And its derivatives are treated as raw material monomers for addition polymerization resins. The amount of both reactive monomers used is that of monomers having two or more functional groups and derivatives thereof in the raw material monomers of condensation polymerization resins, and monomers having one functional group and derivatives thereof are raw materials monomers of addition polymerization resins. Among them, 1 to 10 mol% is preferable, and 4 to 8 mol% is more preferable.

  In producing the composite resin in the present invention, the condensation polymerization reaction and the addition polymerization reaction are preferably performed in the same reaction vessel. In addition, the progress and completion of each polymerization reaction do not need to be simultaneous in time, and the reaction temperature and time may be appropriately selected according to each reaction mechanism to advance and complete the reaction.

That is, as a specific manufacturing method of the composite resin,
i) a method of performing an addition polymerization reaction before the condensation polymerization reaction;
ii) The polycondensation reaction is started prior to the addition polymerization reaction, and after the addition polymerization reaction, a raw material monomer of a trivalent or higher polycondensation resin serving as a crosslinking agent is added to the reaction system as necessary, and the condensation polymerization is performed. A method of further proceeding the condensation polymerization reaction under temperature conditions suitable for the reaction,
iii) Performing addition polymerization reaction and condensation polymerization reaction in parallel under the temperature conditions suitable for addition polymerization reaction, and after completion of the addition polymerization reaction, if necessary, a trivalent or higher condensation polymerization resin that serves as a crosslinking agent Examples thereof include a method in which a monomer is added to the reaction system and the polycondensation reaction further proceeds under temperature conditions suitable for the polycondensation reaction.

  Moreover, in the hybrid resin obtained by using the bireactive monomer as the composite resin, it is preferable that the condensation polymerization resin component and the addition polymerization resin component are partially chemically bonded. As an example, a bifunctional monomer is used together with a raw material monomer of a condensation polymerization resin and / or a raw material monomer of an addition polymerization resin, and preferably used together with a raw material monomer of an addition polymerization resin to add the raw material monomer of the addition polymerization resin. A method in which the condensation polymerization reaction is performed by causing the raw material monomer of the condensation polymerization resin to be present in the addition polymerization reaction system at least at any time before, during and after the polymerization step is preferable.

  The softening point of the composite resin is preferably 90 to 160 ° C, and the glass transition point is preferably 50 to 70 ° C.

  In addition to the binder resin of the present invention, the toner of the present invention includes a colorant, a release agent, a charge control agent, a conductivity regulator, extender pigments, reinforcing fillers such as fibrous substances, antioxidants, and anti-aging agents. An additive such as an agent may be appropriately contained.

  There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is mentioned, According to the objective, it can select suitably. Specifically, carbon black, chrome yellow, hansa yellow, benzidine yellow, selenium yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, balkan orange, watch young red, permanent red, brilliantamine 3B, brilliantamine 6B, dupont oil Various pigments and acridines such as red, pyrazolone red, resol red, rhodamine B lake, lake red C, Bengal, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxalate Xanthene, azo, benzoquinone, azine, anthraquinone, indico, thioindico, phthalocyanine, Phosphorus black dyes, polymethine dyes, triphenylmethane dyes, diphenylmethane dyes, thiazine, various dyes thiazole, etc. may be used in conjunction with one or more kinds.

  As release agents, low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicones; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide and stearic acid amide; carnauba wax, rice wax, candelilla Plant waxes such as wax, tree wax and jojoba oil; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin lux, microcrystalline wax, and Fischer-Tropsch wax. These release agents may be used alone or in combination of two or more.

The toner of the present invention can be produced by a known method such as a kneading and pulverizing method, an emulsion aggregation method, a spray drying method, or a polymerization method. As a general method for producing a pulverized toner by a kneading pulverization method, for example, a raw material such as a binder resin, a colorant, and a charge control agent is uniformly mixed with a mixer such as a ball mill, and then a sealed kneader or a single screw Or the method of melt-kneading with a biaxial extruder etc., cooling, grind | pulverizing, and classifying etc. is mentioned. Furthermore, a fluidity improver such as hydrophobic silica may be added to the coarsely pulverized product in the production process or the surface of the obtained toner, if necessary. The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably from 3 to 15 μm, more preferably from 4 to 10 μm. In the present specification, the volume-median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size.

  The toner of the present invention can be used as a one-component developing toner as it is, or as a two-component developer mixed with a carrier, and can be used in either a one-component developing method or a two-component developing method.

[Softening point of resin]
Using a flow tester (Shimadzu Corporation, CFT-500D), a 1 g sample is heated at a heating rate of 6 ° C / min. While applying a load of 1.96 MPa with a plunger and extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. . Plot the plunger drop amount of the flow tester against the temperature, and let the softening point be the temperature at which half of the sample flows out.

[Glass transition point of resin]
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), the temperature was increased to 200 ° C, and the sample was cooled to 0 ° C at a temperature decrease rate of 10 ° C / min. The temperature at the intersection of the extended line of the baseline below the maximum peak temperature of endotherm and the tangent line indicating the maximum slope from the peak rising portion to the peak apex.

[Volume-median particle diameter of toner (D ₅₀ )]
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 50μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) is dissolved in the electrolytic solution to a concentration of 5% by weight to obtain a dispersion.
Dispersion conditions: 10 mg of a measurement sample is added to 5 mL of the above dispersion, and dispersed for 1 minute with an ultrasonic disperser, then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. Prepare a dispersion.
Measurement conditions: By adding the sample dispersion to 100 mL of the electrolytic solution, the particle size of 30,000 particles is adjusted to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured, Determine the volume median particle size (D ₅₀ ).

Examples 1-10
The raw material monomer of the polycondensation resin of resin composition A shown in Table 1 and the catalyst and sulfonic acid group-containing compound shown in Table 2 are divided into four 5-liter volumes equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple. The reaction mixture was put into a neck flask and subjected to a condensation polymerization reaction at 230 ° C. in a nitrogen atmosphere until the reaction rate reached 90%, and further reacted at 8 kPa until a desired softening point was reached to obtain a binder resin. In the present specification, the reaction rate means the reaction rate between a carboxylic acid component other than fumaric acid and trimellitic anhydride and an alcohol component, and the amount of reaction water produced (mol) / theoretical product water production (mol) × 100. Means a value defined by value.

Example 11
5 liters equipped with a raw material monomer of a condensation polymerization resin other than fumaric acid of resin composition B shown in Table 1, a catalyst and a sulfonic acid group-containing compound shown in Table 2 equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple The resultant was put into a four-necked flask and subjected to a condensation polymerization reaction at 230 ° C. in a nitrogen atmosphere until the reaction rate reached 90%, and further reacted at 8 kPa for 1 hour. Thereafter, the mixture was cooled to 180 ° C., and 2.4 g of fumaric acid and tertiary butyl catechol shown in Table 1 (0.05 parts by weight with respect to 100 parts by weight of the total amount of raw material monomers of the condensation polymerization resin) were added, and the temperature was raised to 210 ° C. for 4 hours The mixture was heated up and reacted at 8 kPa to the desired softening point to obtain a binder resin.

Example 12
The raw material monomer of the condensation polymerization resin other than trimellitic anhydride of the resin composition C shown in Table 1, the catalyst and the sulfonic acid group-containing compound shown in Table 2 were equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. The reaction mixture was placed in a 5-liter four-necked flask and subjected to condensation polymerization under a nitrogen atmosphere at 230 ° C. until the reaction rate reached 90%, and then reacted at 8 kPa for 1 hour. Then, it is cooled to 210 ° C, trimellitic anhydride shown in Table 1 is added, reacted at normal pressure (101.3 kPa) for 1 hour, then reacted to the desired softening point at 8 kPa, and the binder resin Got.

Comparative Example 1
A binder resin was obtained in the same manner as in Example 1 except that the sulfonic acid group-containing compound was not used.

Comparative Example 2
Production of the binder resin was attempted in the same manner as in Example 1 except that no catalyst was used. However, the catalyst activity was low and the binder resin could not be obtained.

Moreover, the symbol in Table 2 means the following.
S1: Tin (II) di-2-ethylhexanoate
S2: Tin distearate (II)
S3: stannous oxide P1: paratoluenesulfonic acid P2: naphthalene-2-sulfonic acid P3: paratoluenesulfonic acid sodium salt

[Reaction activity of binder resin]
In the condensation polymerization reaction, the reaction rate with respect to time (= reaction product water amount / theoretical product water amount × 100) was calculated and plotted from the reaction product water amount. At each time point when the reaction rate reached 30% and 70%, the difference in the reaction rate before and after 30 minutes was calculated, the reaction rate was V30 and V70, and this ratio (V30 / V70) was taken as the reaction activity index. The results are shown in Table 2. A higher reaction activity index indicates that the progress of the reaction is promoted and the reaction time is shortened.

[Evaluation criteria for reaction activity]
◎: 0.40 or more ○: 0.35 or more, less than 0.40 △: 0.25 or more, less than 0.35 ×: Less than 0.25

Toner Production Examples 1 to 13 (Examples 13 to 24 and Comparative Example 3)
100 parts by weight of binder resin shown in Table 3, 4 parts by weight of carbon black “MOGUL L” (Cabot), 1 part by weight of negative charge control agent “Bontron S-34” (Orient Chemical Industries) and polypropylene After thoroughly mixing the wax “NP-105” (Mitsui Chemicals, melting point 140 ° C.) with a Henschel mixer, using a co-rotating twin screw extruder, the roll rotation speed is 200 r / min and the heating temperature in the roll is 80 ° C. Melt kneaded. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized with a jet mill and classified to obtain a powder having a volume median particle size (D ₅₀ ) of 8.0 μm.

  To 100 parts by weight of the obtained powder, 1.0 part by weight of “Aerosil R-972” (manufactured by Nippon Aerosil Co., Ltd.) as an external additive was added and mixed with a Henschel mixer to obtain a toner.

Toner Production Example 14 (Example 25)
The volume-median particle size (D ₅₀ ) was the same as in Toner Production Example 1 except that 100 parts by weight of the binder resin shown in Table 3 was used and 4 parts by weight of a cyan pigment (phthalocyanine copper) was used instead of carbon black. ) To obtain a 8.3 μm cyan toner.

Toner Production Example 15 (Example 26)
100 parts by weight of the binder resin shown in Table 3, 67 parts by weight of magnetic powder “MTS106HD” (manufactured by Toda Kogyo Co., Ltd.), 0.5 part by weight of negative charge control agent “T-77” (manufactured by Hodogaya Chemical Co., Ltd.), polyethylene After thoroughly mixing 2 parts by weight of wax “C-80” (manufactured by Sasol, melting point: 82 ° C.) and 2 parts by weight of polypropylene wax “NP-105” (melting point: 140 ° C.) with a Henschel mixer The kneaded portion was melt kneaded using a co-rotating twin screw extruder having a total length of 1560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm. The heating temperature in the roll was 140 ° C., and the roll rotation speed was 150 r / min. The obtained kneaded material was rolled with a cooling roll, mechanically pulverized, and classified to obtain a magnetic toner having a volume-median particle size (D ₅₀ ) of 9.0 μm.

Test example 1 [saturated charge amount]
0.6g of toner and 19.4g of silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size 90μm) are placed in a 50mL plastic bottle, mixed at 250r / min using a ball mill, and the charge amount is q / m meter ( EPPING). After a mixing time of 600 seconds, a specified amount of developer was put into a cell attached to the q / m meter, and only the toner was sucked through a sieve having a mesh size of 32 μm (stainless steel, twill, wire diameter: 0.0035 mm) for 90 seconds. The voltage change on the carrier generated at that time was monitored, and the saturated charge amount level was evaluated with the charge amount after the mixing time of 600 seconds as the saturated charge amount according to the following evaluation criteria. The results are shown in Table 3.

[Evaluation criteria for saturation charge]
◎: Absolute value of saturation charge is 30μC / g or more ○: Absolute value of saturation charge is 20μC / g or more, less than 30μC / g △: Absolute value of saturation charge is 15μC / g or more, less than 20μC / g × : Absolute value of saturation charge is 10μC / g or more and less than 15μC / g XX: Absolute value of saturation charge is less than 10μC / g

Test Example 2 [Charging Rise]
0.6g of toner and 19.4g of silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size 90μm) are placed in a 50mL plastic bottle, mixed at 250r / min using a ball mill, and the charge amount is q / m meter ( EPPING). After a predetermined mixing time, a specified amount of developer was put into a cell attached to the q / m meter, and only the toner was sucked through a sieve having a mesh size of 32 μm (stainless steel, twill, wire diameter: 0.0035 mm) for 90 seconds. The voltage change on the carrier generated at that time was monitored, and the rising property of charging was evaluated according to the following evaluation criteria. The ratio of the charge amount after 15 seconds of mixing time and the maximum charge amount during mixing time of 600 seconds (charge amount after mixing time of 15 seconds / maximum charge amount after mixing time of 600 seconds) was calculated as the charge rising property. . The results are shown in Table 3.

[Evaluation criteria for charging rise]
◎: 0.6 or more ○: 0.5 or more, less than 0.6 △: 0.4 or more, less than 0.5 ×: Less than 0.4

  From the above results, the toner containing the binder resin of the example having a high reaction activity index and a small thermal history as compared with the toner containing the binder resin of the comparative example has a charge rising property and a saturated charge amount. It turns out that both are excellent. From the results of the toners of Examples 25 and 26, it can be seen that the binder resin of the present invention exhibits good chargeability even in color toners and magnetic toners.

  The binder resin of the present invention is suitably used as a binder resin for toner used for developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (5)

The presence of tin having no Sn-C bond (II) compound and a sulfonic acid group-containing compound, an electron comprising a polycondensation resin obtained by the raw material monomers by polycondensing contain including forming Chakujushi A photographic toner, wherein the weight ratio of the sulfonic acid group-containing compound and the tin (II) compound having no Sn—C bond [the sulfonic acid group-containing compound / tin having no Sn—C bond ( II) Toner for electrophotography wherein compound] is 0.0005-10 . Sn-C bonds and has no tin (II) tin compounds having Sn-O bonds (II) compounds that claim 1 electrophotographic toner chromatography according. The amount of tin (II) compound having no Sn-C bond is 0.01 to 2.0 parts by weight and the amount of sulfonic acid group-containing compound is 0.001 to 100 parts by weight of the total amount of raw material monomers of the condensation polymerization resin. 1.0 parts by weight claim 1 or 2 for electrophotography toner chromatography according. The tin (II) compound having a Sn-O bond is a tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms or a dialkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms. The toner for electrophotography according to 2 or 3. Claim 1 or electrophotographic toner over according sulfonic acid group-containing compound is an aromatic sulfonic acid group-containing compound.