JP6071791B2 - Binder resin composition for polyester toner - Google Patents

Description

  The present invention relates to a binder resin composition for a polyester toner used for developing a latent image formed in an electrophotographic method, a method for producing the binder resin composition, and an electrostatic charge containing the binder resin composition. The present invention relates to an image developing toner.

  In the field of electrophotography, with the development of an electrophotographic system, development of toner for electrophotography corresponding to higher image quality and higher speed is required.

  In response to higher image quality and higher speed, polyester resin, which is easy to adjust the composition, is widely used as a binder resin for toners, especially to improve thermal properties. Attempts have been made to combine them.

  For example, Patent Document 1 contains at least one cyclic compound selected from cyclic oligomers and cyclic polymers having substantially no end groups for the purpose of achieving both chargeability and fixing properties and improving image quality. An electrophotographic toner is disclosed.

  Patent Document 2 discloses a process of melt-kneading a toner material containing a binder resin with a continuous open roll kneader for the purpose of reducing the amount of residual styrene in order to improve problems such as odor. The binder resin is obtained by polymerizing a raw material monomer of a polycondensation resin and a raw material monomer of an addition polymerization resin containing styrene, and has a styrene content of 3 An electrophotographic toner is disclosed, which contains 40 to 100% by weight of a composite resin of -100 ppm in the binder resin.

  Patent Document 3 discloses that the binder resin is continuously used in an electrophotographic toner containing at least a binder resin and a colorant in order to stabilize the charge amount and image quality and to enable fixing at a low temperature. An electron characterized by comprising a polycondensation resin that forms a phase and an addition polymerization resin that forms a dispersed phase, and the dispersed phase having a diameter of 2 μm or less in the resin cross section accounts for 90% or more of the entire cross-sectional area of the dispersed phase A photographic toner is disclosed.

JP 2003-186236 A JP 2007-333802 A JP-A-7-98518

  As disclosed in Patent Documents 2 and 3, a composite resin having a polycondensation resin such as polyester and an addition polymerization resin in one molecule is used in order to achieve both advantages of each resin. . Thus, it is expected that the molecular weight is increased by compounding the resin, and the heat resistant storage stability of the obtained toner is improved. However, the resins disclosed in Patent Documents 2 and 3 are insufficient.

  On the other hand, the addition polymerization resin has a polyethylene main chain, and in particular, when a hydrocarbon monomer such as styrene is used, the polarity becomes low, and this is because the dispersion of the pigment having polarity is adversely affected. There is a problem that the color developability of the toner is inferior and the image quality is lowered.

  In order to improve the affinity with the pigment and increase the dispersibility, it is conceivable to lower the molecular weight. However, in that case, the heat resistant storage stability is further lowered, and it is difficult to achieve both.

  The present inventors have considered that the factors affecting the color developability and heat-resistant storage stability of the resulting toner are due to the structure and composition of the polyester in the binder resin composition. As a result, a binder resin composition for toner containing a cyclic polyester composed of a specific carboxylic acid component and a composite resin composed of a polyester resin portion and a vinyl-based resin portion exhibits good color development and heat-resistant storage stability. As a result, the present invention has been completed.

  The present invention relates to a method for producing a polyester resin binder resin composition excellent in color developability and heat-resistant storage stability of the obtained toner, and to an electrostatic charge image developing toner containing the polyester toner binder resin composition. .

The present invention
[1] A polyester resin binder resin composition comprising a cyclic polyester (A) and a composite resin (B), wherein the cyclic polyester (A) has a carboxylic acid component having 2 to 6 carbon atoms. An aliphatic dicarboxylic acid compound is contained, and the composite resin (B) is composed of a polyester resin portion and a vinyl resin portion, and the mass ratio of the cyclic polyester (A) and the composite resin (B) in the binder resin composition ( A binder resin composition for a polyester toner, wherein the cyclic polyester (A) / composite resin (B)) is 0.01 / 99.99 to 4.0 / 96.0.
[2] A toner for developing an electrostatic image comprising the binder resin composition for a polyester toner according to [1], and [3] a binder resin composition for a polyester toner according to [1]. A manufacturing method of
(i) After the step (A) of performing a polycondensation reaction with a raw material monomer of a polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst, A method of performing the step (B) of performing an addition polymerization reaction with a raw material monomer, or
(ii) After the step (B) of the addition polymerization reaction with the raw material monomer of the vinyl resin portion, the raw material of the polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst A resin having a polycondensation reaction rate of 70% or more and less than 100% is obtained by the method of performing the step (A) of performing a polycondensation reaction with a monomer, and further, a polycondensation reaction is performed at 200 to 250 ° C. in the presence of a rare earth catalyst. The present invention relates to a method for producing a binder resin composition for a polyester toner, wherein step (C) for carrying out a condensation reaction is performed.

  The binder resin composition for a polyester-based toner according to the present invention exhibits an excellent effect that the toner obtained has excellent color developability and heat-resistant storage stability.

  The polyester resin binder resin composition of the present invention is a polyester toner binder resin composition comprising a cyclic polyester (A) and a composite resin (B). The acid component contains an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms, the composite resin (B) is composed of a polyester resin portion and a vinyl resin portion, and the cyclic polyester (A) in the binder resin composition; The mass ratio of the composite resin (B) (cyclic polyester (A) / composite resin (B)) is 0.01 / 99.99 to 4.0 / 96.0.

  The reason why the toner using the binder resin composition for a polyester-based toner of the present invention is excellent in color developability and heat-resistant storage stability is not clear, but is considered as follows.

  The binder resin composition for a polyester toner of the present invention includes a composite resin (B) composed of a cyclic polyester (A), a polyester resin portion, and a vinyl resin portion. Among these, the cyclic polyester is likely to bleed out on the toner surface because of its low molecular weight, but since the molecule does not have a terminal, the mobility of the molecular chain is low, which is considered to contribute to the improvement of heat resistant storage stability.

  Furthermore, the cyclic polyester of the present invention is made from an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms. Polyesters made from aliphatic dicarboxylic acid compounds having 2 to 6 carbon atoms have a high ester moiety ratio, so that the polarity is increased and the affinity with the pigment is high. On the other hand, it has an ester part, but does not have a very high polar substituent such as a carboxy group or a hydroxyl group, so it has a high affinity with a composite resin composed of a polyester resin part and a vinyl resin part. It is considered that the color development can be improved.

  Thus, it is considered that the presence of a small amount of cyclic polyester at the interface between the toner surface and the pigment provides a toner having excellent color developability and heat resistant storage stability.

  Hereafter, each component, process, etc. used for this invention are demonstrated.

[Cyclic polyester (A)]
In the present invention, the cyclic polyester (A) contains an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the carboxylic acid component.

  The carbon number of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is 2 to 6, preferably 2 to 4, and more preferably 2 to 3 from the viewpoint of obtaining a cyclic product with good yield. In addition, carbon number is carbon number of a linear or branched hydrocarbon group except a carboxy group, and does not include carbon number of alkyl ester.

  Examples of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms include succinic acid, fumaric acid, maleic acid, adipic acid, malonic acid, glutaric acid, pimelic acid, glutaric acid, anhydrides of these acids, and 1 to 3 carbon atoms. Of these, succinic acid and fumaric acid are preferable, and fumaric acid is more preferable.

  The content of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is preferably 25 mol% or more, more preferably 30 mol% or more from the viewpoint of improving the color developability of the toner in the carboxylic acid component of the cyclic polyester (A). preferable. Further, from the viewpoint of improving the color developability of the toner, 85 mol% or less is preferable, 70 mol% or less is more preferable, and 50 mol% or less is more preferable.

  The carboxylic acid component of the cyclic polyester (A) preferably further contains an aromatic dicarboxylic acid compound from the viewpoint of improving the heat resistant storage stability and chargeability of the toner.

  Examples of the aromatic dicarboxylic acid compound include terephthalic acid, isophthalic acid, anhydrides of these acids, and alkyl (C1-3) esters thereof.

  Molar ratio of aromatic dicarboxylic acid compound to aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the carboxylic acid component of cyclic polyester (A) (aromatic dicarboxylic acid compound / aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms) Is preferably 75/25 to 15/85, more preferably 70/30 to 50/50.

  Examples of carboxylic acid components other than aliphatic dicarboxylic acid compounds having 2 to 6 carbon atoms and aromatic dicarboxylic acid compounds include trivalent or higher polyvalent carboxylic acid compounds such as aliphatic dicarboxylic acid compounds having more than 7 carbon atoms and trimellitic acid Etc.

  As the alcohol component of the cyclic polyester (A), an aromatic diol and an aliphatic diol are preferable from the viewpoint of efficiently obtaining a cyclic structure, and an aromatic diol is more preferable from the viewpoint of improving the durability of the toner.

  The content of the aromatic diol in the alcohol component is preferably 50 mol% or more, more preferably 70 mol% or more, and further preferably 90 to 100 mol%.

  As the aromatic diol, an alkylene oxide adduct of bisphenol A is preferable. As the alkylene oxide adduct of bisphenol A, the formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is an ethylene and / or propylene group, x and y indicate the number of added moles of alkylene oxide, each being a positive number, and the sum of x and y. 1 to 16 is preferable, 1 to 8 is more preferable, and 1.5 to 4 is more preferable)
An alkylene oxide adduct of bisphenol A represented by the formula: is preferred, and a propylene oxide adduct of bisphenol A in which R is a propylene group is more preferred.

  In the alcohol component, the content of the bisphenol A alkylene oxide adduct is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and further preferably 90 to 100 mol%, from the viewpoint of improving the durability of the toner. preferable.

  Examples of the aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, and the like.

  Other alcohol components include trihydric or higher polyhydric alcohols such as glycerin.

  The alcohol component may contain a monovalent alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound as appropriate.

  Although there is no restriction | limiting in the method of manufacturing cyclic polyester (A), as mentioned later, manufacturing by polycondensing an alcohol component, a carboxylic acid component, and / or polyester at 200-250 degreeC in presence of a rare earth catalyst. Is preferred.

  The number average molecular weight of the cyclic polyester (A) is preferably 250 or more, more preferably 300 or more, and further preferably 400 or more in terms of polystyrene, from the viewpoint of improving the heat resistant storage stability and color developability of the toner. Further, from the viewpoint of improving the heat resistant storage stability and color developability of the toner, it is preferably 1000 or less and more preferably 500 or less in terms of polystyrene. The number average molecular weight is measured by the method described in the examples.

  Since the cyclic polyester (A) does not have a polyester terminal, the cyclic polyester (A) has a remarkably low acid value and hydroxyl value. That is, the acid value is preferably 0.1 mgKOH / g or less, and more preferably 0 mgKOH / g. The hydroxyl value is preferably 0.1 mgKOH / g or less, more preferably 0 mgKOH / g. An acid value and a hydroxyl value are measured by the method as described in an Example.

[Composite resin (B)]
In the present invention, the composite resin (B) is composed of a polyester resin portion and a vinyl resin portion, and is obtained by polymerizing a raw material monomer for the polyester resin portion and a raw material monomer for the vinyl resin portion.

  An alcohol component and a carboxylic acid component are used as raw material monomers for the polyester resin portion.

  As the alcohol component of the polyester resin portion, an aromatic diol and an aliphatic diol are preferable from the viewpoint of improving the durability of the toner, and an aromatic diol is more preferable from the viewpoint of improving the durability of the toner.

  The content of the aromatic diol in the alcohol component is preferably 50 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 90 to 100 mol%.

  As the aromatic diol, an alkylene oxide adduct of bisphenol A is preferable. The alkylene oxide adduct of bisphenol A is preferably an alkylene oxide adduct of bisphenol A represented by the above formula (I), and more preferably a propylene oxide adduct of bisphenol A in which R is a propylene group.

  In the alcohol component, the content of the bisphenol A alkylene oxide adduct is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and further preferably 90 to 100 mol%, from the viewpoint of improving the durability of the toner. preferable.

  Examples of the aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, and the like.

  Other alcohol components include trihydric or higher polyhydric alcohols such as glycerin.

  The carboxylic acid component in the polyester resin portion preferably contains an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms from the viewpoint of improving the heat resistant storage stability and color developability of the toner.

  2-4 are preferable and, as for carbon number of a C2-C6 aliphatic dicarboxylic acid compound, 2-3 are more preferable. In addition, carbon number is carbon number of a linear or branched hydrocarbon group except a carboxy group, and does not include carbon number of alkyl ester.

  Examples of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms include succinic acid, fumaric acid, maleic acid, adipic acid, malonic acid, glutaric acid, pimelic acid, glutaric acid, anhydrides of these acids, and 1 to 3 carbon atoms. Among these, succinic acid and fumaric acid are preferable, and fumaric acid is more preferable.

  The content of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is preferably 25 mol% or more, more preferably 30 mol% or more, from the viewpoint of improving the color developability of the toner in the carboxylic acid component of the polyester resin portion. Further, from the viewpoint of improving the color developability of the toner, 85 mol% or less is preferable, 70 mol% or less is more preferable, and 50 mol% or less is more preferable.

  The carboxylic acid component in the polyester resin portion preferably further contains an aromatic dicarboxylic acid compound from the viewpoint of improving the heat resistant storage stability and chargeability of the toner.

  Examples of the aromatic dicarboxylic acid compound include terephthalic acid, isophthalic acid, anhydrides of these acids, and alkyl (C1-3) esters thereof.

  The content of the aromatic dicarboxylic acid compound is preferably 15 mol% or more, more preferably 30 mol% or more, further preferably 50 mol% or more in the carboxylic acid component. Moreover, 75 mol% or less is preferable, 75 mol% or less is more preferable, and 70 mol% or less is further more preferable.

  The molar ratio of the aromatic dicarboxylic acid compound and the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the carboxylic acid component of the polyester resin portion (aromatic dicarboxylic acid compound / aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms) is: 75 / 25-15 / 85 are preferable, and 70 / 30-50 / 50 are more preferable.

  Examples of carboxylic acid components other than aliphatic dicarboxylic acid compounds having 2 to 6 carbon atoms and aromatic dicarboxylic acid compounds include trivalent or higher polyvalent carboxylic acid compounds such as aliphatic dicarboxylic acid compounds having more than 7 carbon atoms and trimellitic acid Etc.

  The alcohol component may contain a monovalent alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound as appropriate.

  The vinyl resin part preferably contains one or more selected from styrene monomers and (meth) acrylate monomers as structural units.

  Examples of the styrene monomer include styrene derivatives such as styrene and α-methylstyrene.

  Examples of (meth) acrylic acid ester monomers include alkyl (1 to 18 carbon atoms) esters of (meth) acrylic acid, dimethylaminoethyl (meth) acrylate, and the like.

  The content of the styrene monomer or (meth) acrylic acid ester monomer, or the total content of both is preferably 70 to 100% by mass from the viewpoint of improving the heat resistant storage stability of the toner in the raw material monomer of the vinyl resin part. 80-100 mass% is more preferable, and 90-100 mass% is still more preferable.

  Monomers other than styrene monomers and (meth) acrylic acid ester monomers include ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; vinyl acetate and vinyl propionate And vinyl esters.

  From the viewpoint of enhancing the dispersibility of the vinyl resin part to the polyester resin part and expressing the effect of the present invention, the composite resin (B) is added to the raw material monomer of the polyester resin part and the raw material monomer of the vinyl resin part, Furthermore, a resin (hybrid resin) obtained by using both reactive monomers capable of reacting with both the raw material monomer of the polyester resin portion and the raw material monomer of the vinyl resin portion is preferable. Accordingly, when the raw material monomer for the polyester resin portion and the raw material monomer for the vinyl resin portion are polymerized to obtain a composite resin, the polycondensation reaction and / or the addition polymerization reaction are preferably performed in the presence of both reactive monomers. . As a result, the composite resin becomes a resin (hybrid resin) in which the polyester resin portion and the vinyl resin portion are bonded via the structural unit derived from the both reactive monomers, and the polyester resin portion and the vinyl resin portion become finer. And uniformly dispersed.

  That is, the composite resin (B) comprises a polyester resin part raw material monomer, a vinyl resin part raw material monomer, and a polyester resin part raw material monomer and a vinyl resin part raw material monomer capable of reacting with both. It is preferable that it is resin obtained by polymerizing.

  As the both reactive monomers, 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, preferably a hydroxyl group and / or in the molecule. A compound having a carboxyl group, more preferably a carboxyl group, and an ethylenically unsaturated bond is preferred, and by using such a bireactive monomer, the dispersibility of the resin that becomes the dispersed phase can be further improved. Among these, (meth) acrylic acid is preferable from the viewpoint of the reactivity of the polycondensation reaction and the addition polymerization reaction.

  The amount of both reactive monomers used is to increase the dispersibility of the vinyl-based resin portion in the polyester resin portion and to control the addition polymerization reaction and the polycondensation reaction. 1 to 30 mol is preferable, 2 to 20 mol is more preferable, 5 to 15 mol is more preferable, and the total amount of the raw material monomers of the vinyl-based resin part (not including the polymerization initiator) ) 2 to 30 mol is preferable with respect to 100 mol, and 5 to 20 mol is more preferable.

  In the composite resin, the mass ratio of the polyester resin portion to the vinyl resin portion [polyester resin portion / vinyl resin portion] is such that the continuous phase is a polyester resin and the dispersed phase is a vinyl resin, From the viewpoint of improving the heat resistant storage stability, 50/50 to 95/5 is preferable, 70/30 to 95/5 is more preferable, and 80/20 to 95/5 is more preferable. In the above calculation, the amount of both reactive monomers is included in the polyester resin portion. The amount of the polymerization initiator is not included in the vinyl resin part.

  The softening point of the composite resin (B) is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and further preferably 100 ° C. or higher, from the viewpoint of improving the heat resistant storage stability of the toner. Further, from the viewpoint of improving the color developability and fixability of the toner, 130 ° C. or lower is preferable, 120 ° C. or lower is more preferable, and 115 ° C. or lower is further preferable.

  The glass transition temperature of the composite resin (B) is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 60 ° C. or higher, from the viewpoint of improving the heat resistant storage stability of the toner. Further, from the viewpoint of improving the color developability and fixability of the toner, it is preferably 75 ° C. or lower, more preferably 73 ° C. or lower, and even more preferably 70 ° C. or lower.

  From the viewpoint of improving the charging stability of the toner, the acid value of the composite resin (B) is preferably 10 mgKOH / g or more, more preferably 15 mgKOH / g or more, and further preferably 20 mgKOH / g or more. Further, from the viewpoint of improving the color development property and charging stability of the toner, it is preferably 40 mgKOH / g or less, more preferably 30 mgKOH / g or less, further preferably 25 mgKOH / g or less, and further preferably 22 mgKOH / g or less.

  In addition, the softening point, glass transition temperature, and acid value of the composite resin (B) are obtained by the methods described in the examples.

[Method for producing binder resin composition for toner]
The cyclic polyester (A) is preferably produced by a method including a step of polycondensing an alcohol component and a carboxylic acid component and / or polyester at 200 to 250 ° C. in the presence of a rare earth catalyst. For the production of the cyclic polyester (A), in addition to the alcohol component and the carboxylic acid component, a polyester may be used. From the viewpoint of appropriately adjusting the molecular weight of the obtained cyclic polyester (A), the alcohol component and the carboxylic acid are used. It is preferable to use only the components.

  The rare earth catalyst is preferably an inorganic acid salt or an organic acid salt of a rare earth element from the viewpoint of efficiently obtaining the cyclic polyester (A), more preferably an organic acid salt, and further preferably a sulfonate salt from the viewpoint of reaction efficiency.

  As the rare earth element, lanthanoids such as scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, etc. are preferable, scandium, lanthanum, samarium, europium. Erbium, lutetium and ytterbium are more preferred, and scandium, lanthanum, samarium and ytterbium are more preferred.

  As the sulfonate, triflate (trifluoromethanesulfonate), dodecylbenzenesulfonate and toluenesulfonate are preferable, and triflate is more preferable.

  In view of the above, the rare earth element sulfonate is preferably scandium, lanthanum, samarium, or ytterbium triflate, and more preferably scandium (III) triflate.

  The amount of the rare earth catalyst used is preferably 0.01 to 1 part by mass, more preferably 0.03 to 0.8 part by mass, and still more preferably 0.05 to 0.2 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

  The temperature of the polycondensation reaction in the presence of the rare earth catalyst is 200 ° C. or higher, preferably 210 ° C. or higher, from the viewpoint of efficiently obtaining the cyclic polyester (A). And it is 250 degrees C or less, and 245 degrees C or less is preferable. Moreover, it is 200-250 degreeC, 210-250 degreeC is preferable and 210-245 degreeC is more preferable.

  When the polycondensation temperature is 200 ° C. or higher, it is preferable because the cyclic polyester can be sufficiently produced. When the temperature is 250 ° C. or lower, the monomer and polymer are not decomposed and coloring does not occur.

  When the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms contained in the carboxylic acid component is an unsaturated aliphatic dicarboxylic acid compound, the polycondensation reaction is preferably performed in the presence of a radical polymerization inhibitor.

  Examples of the radical polymerization inhibitor include 4-t-butylcatechol.

  The amount of the radical polymerization inhibitor used is preferably 0.001 to 0.5 parts by mass and more preferably 0.01 to 0.1 parts by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

  The polycondensation reaction may be performed by adding raw material monomers at a time and heating, but when the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms contained in the carboxylic acid component is an unsaturated aliphatic dicarboxylic acid compound The raw material monomer other than the unsaturated aliphatic dicarboxylic acid compound is polycondensed at 200 to 250 ° C. in the presence of a rare earth catalyst, and then cooled to 190 ° C. or lower to inhibit radical polymerization with the unsaturated aliphatic dicarboxylic acid compound. After adding the agent, it is preferable to carry out polycondensation by heating again to 200 to 250 ° C.

  The molar ratio of the alcohol component to the carboxylic acid component of the cyclic polyester (A) to be subjected to the polycondensation reaction (alcohol component / carboxylic acid component) is preferably 1.5 to 2.5, more preferably 1.7 to 2.3.

  In the production of the cyclic polyester (A), in order to control the amount of the cyclic polyester (A) in the binder resin composition for toner obtained by mixing with the composite resin (B), the cyclic polyester (A) is purified. It is preferable to do.

  As a purification method, it is preferable to dissolve the reaction mixture in an organic solvent in which the polyester is dissolved, mix the aqueous medium, separate the layers, and remove the aqueous phase.

  The organic solvent used here is preferably a halogen solvent, an ether solvent, an ester solvent, or the like from the viewpoint of the solubility of the polyester, preferably a halogen solvent, and more preferably dichloromethane.

  As the aqueous medium, water is preferable, an aqueous alkaline solution is preferable, and an aqueous ammonia solution is more preferable.

  It is preferable to obtain the cyclic polyester (A) by removing the organic solvent from the organic solvent solution of the polyester obtained by purification.

  The composite resin (B) is, for example, (1) a method in which a raw material monomer of a polyester resin part is polycondensed in the presence of a vinyl resin having a carboxy group or a hydroxyl group (the carboxy group or hydroxyl group is a bireactive monomer or (2) can be obtained by a method of addition polymerization of a vinyl-based resin raw material monomer in the presence of a polyester resin. A resin obtained by polymerizing the raw material monomer of the vinyl resin portion is preferred.

  The temperature during the polycondensation reaction of the raw material monomer in the polyester resin portion is preferably 200 ° C. or higher, more preferably 225 ° C. or higher, from the viewpoint of reactivity. Further, from the viewpoint of thermal decomposability, 250 ° C. or lower is preferable. The temperature during the polycondensation reaction is preferably 200 to 250 ° C, more preferably 225 to 250 ° C.

  The polycondensation reaction may be performed in the presence of an esterification catalyst, an esterification cocatalyst, a polymerization inhibitor, or the like, if necessary. Examples of esterification catalysts include tin catalysts and titanium catalysts. Examples of the tin catalyst include dibutyltin oxide and tin (II) 2-ethylhexanoate. From the viewpoints of reactivity, molecular weight adjustment and resin physical property adjustment, Sn such as tin (II) 2-ethylhexanoate is used. Tin (II) compounds having no —C bond are preferred. Examples of the titanium catalyst include titanium diisopropylate bistriethanolamate. The amount of the esterification catalyst used is preferably 0.01 to 1.5 parts by mass, more preferably 0.1 to 1.0 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Examples of the esterification promoter include gallic acid. The amount of the esterification cocatalyst used is preferably 0.001 to 0.5 parts by mass, more preferably 0.01 to 0.1 parts by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Examples of the polymerization inhibitor include tert-butylcatechol. The amount of the polymerization inhibitor used is preferably 0.001 to 0.5 parts by mass and more preferably 0.01 to 0.1 parts by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

  The temperature during the addition polymerization reaction is preferably 140 ° C. or higher, and more preferably 150 ° C. or higher, from the viewpoints of reactivity and molecular weight adjustment. From the viewpoint of reactivity and molecular weight adjustment, 200 ° C. or lower is preferable, and 180 ° C. or lower is more preferable.

  Moreover, you may perform addition polymerization reaction in presence of a polymerization initiator etc. as needed. Examples of the polymerization initiator include peroxides such as dibutyl peroxide and dicumyl peroxide. As for the usage-amount of a polymerization initiator, 3-12 mass parts is preferable with respect to 100 mass parts of raw material monomers of a vinyl-type resin part.

  The composite resin (B) is specifically obtained by the following method. In the case of using the bireactive monomer, it is preferable to use it for the addition polymerization reaction together with the raw material monomer of the vinyl resin portion from the viewpoint of expressing the effect of the present invention by controlling the addition polymerization reaction and the polycondensation reaction.

(i) A method of performing a step (B) of an addition polymerization reaction with a raw material monomer (and a bireactive monomer) of a vinyl resin portion after the step (A) of the polycondensation reaction with the raw material monomer of the polyester resin portion. The step (A) is carried out under reaction temperature conditions suitable for the polycondensation reaction, the reaction temperature is lowered, and the step (B) is carried out under temperature conditions suitable for the addition polymerization reaction. When using both reactive monomers, it is preferable to add it to the reaction system together with the raw material monomer of the vinyl resin portion at a temperature suitable for the addition polymerization reaction. Both reactive monomers undergo an addition polymerization reaction and also react with the polyester resin portion.
When using a raw material monomer of a trivalent or higher valent polyester resin as a crosslinking agent, the reaction temperature is increased again after the step (B), and the trivalent or higher raw material monomer is converted into an esterification catalyst, if necessary. It is preferable to add to the polymerization system together with an esterification cocatalyst and the like to further advance the polycondensation reaction in step (A) and the reaction with both reactive monomers.

(ii) Method of performing the step (A) of the polycondensation reaction with the raw material monomer of the polyester resin portion after the step (B) of the addition polymerization reaction with the raw material monomer (and both reactive monomers) of the vinyl resin portion. The step (B) is carried out under reaction temperature conditions suitable for the addition polymerization reaction, the reaction temperature is raised, and the polycondensation reaction in step (A) is carried out under temperature conditions suitable for the polycondensation reaction. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.
The raw material monomer for the polyester resin portion may be present in the reaction system during the addition polymerization reaction, or may be added to the reaction system under temperature conditions suitable for the polycondensation reaction. In the former case, the progress of the polycondensation reaction can be controlled by adding an esterification catalyst at a temperature suitable for the polycondensation reaction.

(iii) A method in which the step (A) of the polycondensation reaction with the raw material monomer in the polyester resin portion and the step (B) of the addition polymerization reaction with the raw material monomer (and both reactive monomers) in the vinyl resin portion are performed in parallel. In the method, step (A) and step (B) are performed under reaction temperature conditions suitable for the addition polymerization reaction. In the case of using a raw material monomer of a trivalent or higher polyester resin part as a crosslinking agent, after the completion of the step (B), the reaction temperature is increased and the trivalent or higher valence is increased under a temperature condition suitable for the polycondensation reaction. It is preferable that the raw material monomer is added to the polymerization system together with an esterification catalyst, an esterification cocatalyst, and the like, if necessary, and the polycondensation reaction in the step (A) is further performed. At that time, under a temperature condition suitable for the polycondensation reaction, a radical polymerization inhibitor can be added to advance only the polycondensation reaction. Both reactive monomers are involved in the polycondensation reaction as well as the addition polymerization reaction.

  In the method (i), a prepolymerized polycondensation resin may be used in place of the step (A) for performing the polycondensation reaction. In the method (iii), when the step (A) and the step (B) are performed in parallel, the mixture containing the raw material monomer for the vinyl resin part in the mixture containing the raw material monomer for the polyester resin part. It can also be made to react by dripping.

  The methods (i) to (iii) are preferably performed in the same container.

  In the present invention, the method (i) is preferable from the viewpoint of improving the heat resistant storage stability of the toner. When the carboxylic acid component contains an unsaturated aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms, the raw material monomer of the polyester resin other than the unsaturated aliphatic dicarboxylic acid compound is subjected to step (A), and after step (B), The reaction temperature is raised again to a temperature suitable for the polycondensation reaction, and then cooled to 190 ° C. or less. After adding the unsaturated aliphatic dicarboxylic acid compound and the radical polymerization inhibitor, the reaction temperature is raised again, and the step ( It is preferable to further advance the polycondensation reaction of A) and the reaction with both reactive monomers.

  The molar ratio (alcohol component / carboxylic acid component) of the alcohol component and the carboxylic acid component of the polyester resin portion used for the polycondensation reaction is preferably 0.8 to 1.5, more preferably 1.0 to 1.3.

  The binder resin composition of the present invention can be obtained by mixing the cyclic polyester (A) obtained by the above method and the composite resin (B). It is preferable that the cyclic polyester (A) and the composite resin (B) are mixed and melted to make them uniform, and more preferably melt-kneaded.

  For example, the cyclic polyester (A) and the composite resin (B) are uniformly mixed with a mixer such as a Henschel mixer, and then melt-kneaded with a closed kneader, a single or twin screw extruder, an open roll kneader, or the like. It is preferable to cool.

  The mixing of the cyclic polyester (A) and the composite resin (B) may be performed in a step of mixing raw materials other than the resin when the toner is manufactured. Depending on the type of toner, the cyclic polyester (A) and the composite resin (B) Since the ratio of the resin (B) can be easily changed, it is preferably performed when the toner is produced.

As described above, the binder resin composition of the present invention can be obtained by mixing the cyclic polyester (A) and the composite resin (B).
(i) After the step (A) of performing a polycondensation reaction with a raw material monomer of a polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst, A method of performing the step (B) of performing an addition polymerization reaction with a raw material monomer, or
(ii) After the step (B) of the addition polymerization reaction with the raw material monomer of the vinyl resin portion, the raw material of the polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst A resin having a polycondensation reaction rate of 70% or more and less than 100% is obtained by the method of performing the step (A) of performing a polycondensation reaction with a monomer, and further, a polycondensation reaction is performed at 200 to 250 ° C. in the presence of a rare earth catalyst. The binder resin composition for toner can also be obtained by the method of performing the step (C) of performing the condensation reaction. This is because when the composite resin is produced, the obtained composite resin is further subjected to a polycondensation reaction in the presence of a rare earth catalyst to produce the cyclic polyester (A), thereby producing the cyclic polyester (A). And a composite resin (B). This method is preferable from the viewpoint of obtaining a binder resin composition excellent in color developability and heat-resistant storage stability of the obtained toner, and the color developability and heat-resistant storage stability of the obtained toner can be easily adjusted to a necessary range. From the viewpoint, a method of mixing the previously obtained cyclic polyester (A) and the composite resin (B) is preferable. This method is more preferable from the viewpoint of achieving both color developability, heat-resistant storage stability and production efficiency of the obtained toner.

  The raw material monomer is as described in the composite resin (B) except that an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is used for the carboxylic acid component of the polyester resin component. The content of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is preferably 25 mol% or more, more preferably 30 mol% or more from the viewpoint of improving the color developability of the toner in the carboxylic acid component. Further, from the viewpoint of improving the color developability of the toner, 85 mol% or less is preferable, 70 mol% or less is more preferable, and 50 mol% or less is more preferable.

  When using both reactive monomers, it is preferable to add together with the raw material monomer of the vinyl resin in the step (B).

  The conditions for the polycondensation reaction in step (A) and the addition polymerization reaction in step (B) are the same as described for composite resin (B) unless otherwise specified.

  The titanium catalyst or tin catalyst used as the esterification catalyst in the step (A) is preferably a tin catalyst from the viewpoint of promptly reaching the target reaction rate and suppressing coloring.

  As the titanium catalyst, a titanium compound having a Ti-O bond is preferable, and a compound having an alkoxy group having 1 to 28 carbon atoms, an alkenyloxy group having 2 to 28 carbon atoms, or an acyloxy group having 1 to 28 carbon atoms in total. More preferred is titanium diisopropylate bistriethanolamate.

  Examples of the tin catalyst include dibutyltin oxide, but a tin (II) compound having no Sn—C bond is preferable, and tin (II) 2-ethylhexanoate is more preferable.

  The amount of the esterification catalyst used is preferably 0.01 to 2.0 parts by mass, more preferably 0.1 to 1.5 parts by mass, and still more preferably 0.2 to 1.0 parts by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

  In the step (A), the use of a compound having a benzene ring in which hydrogen atoms bonded to three adjacent carbon atoms are substituted with a hydroxyl group as a co-catalyst together with the esterification catalyst is a viewpoint of improving the reactivity. To preferred.

  Examples of the compound having a benzene ring in which hydrogen atoms bonded to three carbon atoms adjacent to each other are substituted with a hydroxyl group include pyrogallol compounds. Examples of pyrogallol compounds include pyrogallol, gallic acid, gallic acid esters, benzophenone derivatives such as 2,3,4-trihydroxybenzophenone, 2,2 ', 3,4-tetrahydroxybenzophenone, and the like from the viewpoint of reactivity. , Pyrogallol, gallic acid, alkyl esters having an alkyl group having 1 to 12 carbon atoms of gallic acid, and the like, and alkyl esters having an alkyl group having 1 to 12 carbon atoms of gallic acid and gallic acid are preferable.

  From the viewpoint of reactivity, the mass ratio of the cocatalyst to the catalyst (cocatalyst / catalyst) is preferably 0.01 or more, more preferably 0.02 or more, and further preferably 0.03 or more. And 0.5 or less is preferable, 0.3 or less is more preferable, 0.2 or less is further more preferable.

  The polycondensation reaction in the step (A) is performed until the reaction rate becomes 70% or more and less than 100%, and from the viewpoint of adjusting the abundance ratio, molecular weight, etc. of the cyclic polyester (A), until the reaction rate becomes 80% or more and less than 100%. Preferably it is done. The reaction rate in the present invention refers to a value of product reaction water amount (mol) / theoretical product water amount (mol) × 100.

  After step (A) and step (B), a part of the polyester resin part polycondensed in step (A) is cyclized by polycondensation in the presence of a rare earth catalyst at 200 to 250 ° C. Generate.

  The rare earth catalyst used in the step (C) is preferably an inorganic acid salt or an organic acid salt of a rare earth element from the viewpoint of efficiently obtaining the cyclic polyester (A), and more preferably an organic acid salt from the viewpoint of reaction efficiency. Acid salts are more preferred.

  As the rare earth element, lanthanoids such as scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, etc. are preferable, scandium, lanthanum, samarium, europium. Erbium, lutetium and ytterbium are more preferred, and scandium, lanthanum, samarium and ytterbium are more preferred.

  As the sulfonate, triflate (trifluoromethanesulfonate), dodecylbenzenesulfonate and toluenesulfonate are preferable, and triflate is more preferable.

  In view of the above, the rare earth element sulfonate is preferably scandium, lanthanum, samarium, or ytterbium triflate, and more preferably scandium (III) triflate.

  The amount of the rare earth catalyst used is preferably 0.01 to 1 part by mass, more preferably 0.03 to 0.8 part by mass, and still more preferably 0.05 to 0.2 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component.

  In the step (C), from the viewpoint of efficiently obtaining the cyclic polyester (A), the polycondensation temperature in the presence of the rare earth catalyst is 200 ° C. or higher, and preferably 210 ° C. or higher. And it is 250 degrees C or less, and 245 degrees C or less is preferable. Moreover, it is 200-250 degreeC, 210-250 degreeC is preferable and 210-245 degreeC is more preferable.

  When the polycondensation temperature is 200 ° C. or higher, it is preferable because the cyclic polyester can be sufficiently produced. When the temperature is 250 ° C. or lower, the monomer and polymer are not decomposed and coloring does not occur.

  The amount of cyclic polyester produced can be confirmed by liquid chromatography-mass spectrometry (LC-MS) or the like, and can be appropriately adjusted depending on the reaction temperature and reaction time.

[Binder resin composition for toner]
The mass ratio of the cyclic polyester (A) and the composite resin (B) in the binder resin composition (cyclic polyester (A) / composite resin (B)) is 0.01 / 99.99 to 4.0 / 96.0. From the viewpoint of improving the low-temperature fixability, 0.05 / 99.95 to 3.0 / 97.0 is preferable, 0.1 / 99.9 to 1.0 / 99.0 is more preferable, and 0.2 / 99.8 to 0.7 / 99.3 is further preferable. Further, from the viewpoint of improving the heat resistant storage stability of the obtained toner, 0.3 / 99.7 to 4.0 / 96.0 is preferable, 0.5 / 99.5 to 4.0 / 96.0 is more preferable, 0.6 / 99.4 to 4.0 / 96.0 is further preferable, and 0.7 / 99.3 -4.0 / 96.0 is even more preferable.

  The softening point of the binder resin composition for toner is preferably 90 ° C. or higher, and more preferably 100 ° C. or higher, from the viewpoint of improving the heat resistant storage stability of the obtained toner. From the viewpoint of improving the low-temperature fixability of the obtained toner, it is preferably 130 ° C. or lower, more preferably 110 ° C. or lower. Moreover, 90-130 degreeC is preferable and 100-110 degreeC is more preferable.

  The glass transition temperature of the binder resin composition for toner of the present invention is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, and further preferably 58 ° C. or higher, from the viewpoint of improving the heat-resistant storage stability of the obtained toner. From the viewpoint of improving the low-temperature fixability of the obtained toner, it is preferably 100 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 70 ° C. or lower. Moreover, 50-100 degreeC is preferable, 55-80 degreeC is more preferable, and 58-70 degreeC is further more preferable.

  The acid value of the binder resin composition for toner is preferably 3 mgKOH / g or more, more preferably 10 mgKOH / g or more, from the viewpoint of improving the heat-resistant storage stability of the obtained toner. And 35 mgKOH / g or less is preferable and 25 mgKOH / g or less is more preferable. 3 to 35 mgKOH / g is preferable, and 10 to 25 mgKOH / g is more preferable.

[Toner for electrostatic image development]
The toner for developing an electrostatic charge image of the present invention can achieve both color developability and heat-resistant storage stability by containing the binder resin composition for toner.

  In the toner of the present invention, known resins other than the binder resin composition for toner may be used in combination as long as the effects of the present invention are not impaired. The content is preferably 70 to 100% by mass, more preferably 80 to 100% by mass, still more preferably 90 to 100% by mass, and even more preferably 100% by mass in the total binder resin composition in the toner. preferable.

  The toner of the present invention includes a colorant, a release agent, a charge control agent, a charge control resin, magnetic powder, a fluidity improver, a conductivity modifier, a reinforcing filler such as a fibrous substance, an antioxidant, and a cleaning property. Additives such as improvers may be contained, and it is preferred that a colorant, a release agent and a charge control agent are contained.

  As the colorant, all of dyes and pigments used as toner colorants can be used, such as carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow and the like can be used, and the toner of the present invention may be either a black toner or a color toner. The content of the colorant is preferably 1 part by mass or more and more preferably 2 parts by mass or more with respect to 100 parts by mass of the binder resin from the viewpoint of improving the toner image density and low-temperature fixability. Moreover, 40 mass parts or less are preferable, and 10 mass parts or less are more preferable.

  As the release agent, low molecular weight polypropylene, low molecular weight polyethylene, low molecular weight polypropylene polyethylene copolymer, aliphatic hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax and oxides thereof, carnauba wax, Examples include ester waxes such as montan wax, sazol wax and their deoxidized wax, fatty acid ester wax, fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts, and the like. It can be used by mixing.

  The melting point of the release agent is preferably 60 to 160 ° C., more preferably 60 to 150 ° C., from the viewpoints of low-temperature fixability and offset resistance of the toner.

  The content of the release agent is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the binder resin from the viewpoint of low-temperature fixability and offset resistance of the toner and dispersibility in the binder resin. More preferably, it is more preferably 1.5 parts by mass or more. Moreover, 10 mass parts or less are preferable, 8 mass parts or less are more preferable, and 7 mass parts or less are further more preferable.

  The charge control agent is not particularly limited, and may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent.

  Examples of positively chargeable charge control agents include nigrosine dyes such as “Nigrosine Base EX”, “Oil Black BS”, “Oil Black SO”, “Bontron N-01”, “Bontron N-04”, “Bontron N-07 ”,“ Bontron N-09 ”,“ Bontron N-11 ”(manufactured by Orient Chemical Co., Ltd.), etc .; triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as“ Bontron ” P-51 "(manufactured by Orient Chemical Industries), cetyltrimethylammonium bromide," COPY CHARGE PX VP435 "(manufactured by Clariant), etc .; polyamine resins such as" AFP-B "(manufactured by Orient Chemical Industries); imidazole derivatives Examples thereof include “PLZ-2001”, “PLZ-8001” (manufactured by Shikoku Kasei Co., Ltd.) and the like; styrene-acrylic resins such as “FCA-701PT” (manufactured by Fujikura Kasei Co., Ltd.) and the like.

  In addition, as a negatively chargeable charge control agent, metal-containing azo dyes such as “Varifirst Black 3804”, “Bontron S-31” (above, manufactured by Orient Chemical Industries), “T-77” (Hodogaya Chemical) Manufactured by Kogyo Co., Ltd.), Bontron S-32, Bontron S-34, Bontron S-36 (above, Orient Chemical Co., Ltd.), Eisenspiron Black TRH (Hodogaya Chemical Co., Ltd.) A metal compound of a benzylic acid compound, such as “LR-147”, “LR-297” (manufactured by Nippon Carlit Co., Ltd.); a metal compound of a salicylic acid compound, such as “Bontron E-81”, “Bontron E- 84, “Bontron E-88”, “E-304” (manufactured by Orient Chemical Co., Ltd.), “TN-105” (manufactured by Hodogaya Chemical Co., Ltd.); copper phthalocyanine dye; quaternary ammonium salt such as “ COPY CHARGE NX VP434 "(manufactured by Clariant), nitroimidazole derivative; organometallic Compounds, for example "TN105" (Hodogaya Chemical Co., Ltd.).

  The content of the charge control agent is preferably 0.01 parts by mass or more, more preferably 0.3 parts by mass or more, further preferably 0.5 parts by mass or more, with respect to 100 parts by mass of the binder resin, from the viewpoint of charging stability of the toner. 1 part by mass or more is more preferable, 10 parts by mass or less is preferable, 5 parts by mass or less is more preferable, 3 parts by mass or less is further preferable, and 2 parts by mass or less is further preferable.

  The toner of the present invention may be a toner obtained by any conventionally known method such as a melt-kneading method, an emulsion phase inversion method, or a polymerization method, but from the viewpoint of productivity and dispersibility of the colorant, A pulverized toner obtained by a melt kneading method is preferred. In the case of pulverized toner by the melt-kneading 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 Henschel mixer, and then a hermetically sealed kneader, a single or twin screw extruder It can be produced by melt-kneading with an open roll kneader or the like, cooling, pulverizing and classifying.

  In the toner of the present invention, an external additive is preferably used in order to improve transferability, and inorganic fine particles are preferably used as the external additive. Examples of the inorganic fine particles include silica, alumina, titania, zirconia, tin oxide and zinc oxide, and silica is preferable.

  Silica is preferably hydrophobic silica that has been subjected to a hydrophobic treatment, from the viewpoint of toner transferability.

  Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. Of these, hexamethyldisilazane is preferred.

  The average particle diameter of the external additive is preferably 10 nm or more, and more preferably 15 nm or more, from the viewpoint of the chargeability, fluidity, and transferability of the toner. Further, it is preferably 250 nm or less, more preferably 200 nm or less, and further preferably 90 nm or less.

  The content of the external additive is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and further preferably 0.3 parts by mass or more with respect to 100 parts by mass of the toner before being processed with the external additive. Moreover, 5 mass parts or less are preferable, and 3 mass parts or less are more preferable.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably 3 to 15 μm, more preferably 3 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. When the toner is treated with an external additive, the volume median particle size of the toner particles before being treated with the external additive is defined as the volume median particle size of the toner.

  The toner of the present invention can be used as a one-component developing toner or as a two-component developer mixed with a carrier.

  In relation to the above-described embodiment, the present invention further discloses the following binder resin composition for a polyester toner, a method for producing the same, and a toner for developing an electrostatic image containing the binder resin composition.

<1> A binder resin composition for a polyester toner containing a cyclic polyester (A) and a composite resin (B), wherein the carboxylic acid component of the cyclic polyester (A) has 2 to 6 carbon atoms. An aliphatic dicarboxylic acid compound is contained, and the composite resin (B) is composed of a polyester resin portion and a vinyl resin portion, and the mass ratio of the cyclic polyester (A) and the composite resin (B) in the binder resin composition ( A binder resin composition for a polyester toner, wherein the cyclic polyester (A) / composite resin (B)) is 0.01 / 99.99 to 4.0 / 96.0.

<2> The binder for a polyester-based toner according to <1>, wherein the content of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is 25 to 85 mol% in the carboxylic acid component of the cyclic polyester (A). Resin composition.
<3> The binder resin composition for a polyester toner according to <1> or <2>, wherein the carboxylic acid component of the cyclic polyester (A) further contains an aromatic dicarboxylic acid compound.
<4> The molar ratio of the aromatic dicarboxylic acid compound to the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the carboxylic acid component of the cyclic polyester (A) (aromatic dicarboxylic acid compound / aliphatic dicarboxylic acid having 2 to 6 carbon atoms) <3> The binder resin composition for a polyester toner according to <3>, wherein the acid compound) is 75/25 to 15/85.
<5> The binder resin composition for a polyester toner according to any one of <1> to <4>, wherein the cyclic polyester (A) has a number average molecular weight of 1000 or less.
<6> Bireactivity in which the composite resin (B) can react with the raw material monomer of the polyester resin portion, the raw material monomer of the vinyl resin portion, and the raw material monomer of the polyester resin portion and the raw material monomer of the vinyl resin portion The binder resin composition for a polyester-based toner according to any one of <1> to <5>, which is a resin obtained by polymerizing a monomer.
<7> The binder for a polyester-based toner according to any one of <1> to <6>, wherein the carboxylic acid component, which is a raw material monomer of the polyester resin portion of the composite resin, contains 15 mol% or more of an aromatic dicarboxylic acid compound. Resin composition.
<8> Any one of <1> to <7>, wherein a mass ratio of the polyester resin portion to the vinyl resin portion (polyester resin portion / vinyl resin portion) in the composite resin is 50/50 to 95/5. Binder resin composition for polyester toner.
<9> The binder for a polyester toner according to any one of <1> to <8>, wherein the vinyl resin portion includes one or more selected from a styrene monomer and a (meth) acrylate monomer as a constituent unit. Resin composition.
<10> The binder resin composition for a polyester toner according to any one of <6> to <9>, wherein the both reactive monomers are (meth) acrylic acid.
<11> The binder resin for a polyester toner according to any one of <1> to <10>, wherein the cyclic polyester (A) has an acid value of 0.1 mgKOH / g or less and a hydroxyl value of 0.1 mgKOH / g or less. Composition.
<12> An electrostatic charge image developing toner comprising the polyester resin binder resin composition according to any one of <1> to <11>.
<13> A method for producing a binder resin composition for a polyester toner according to any one of <1> to <11>,
(i) After the step (A) of performing a polycondensation reaction with a raw material monomer of a polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst, A method of performing the step (B) of performing an addition polymerization reaction with a raw material monomer, or
(ii) After the step (B) of the addition polymerization reaction with the raw material monomer of the vinyl resin portion, the raw material of the polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst A resin having a polycondensation reaction rate of 70% or more and less than 100% is obtained by the method of performing the step (A) of performing a polycondensation reaction with a monomer, and further, a polycondensation reaction is performed at 200 to 250 ° C. in the presence of a rare earth catalyst. A method for producing a binder resin composition for a polyester-based toner, wherein the step (C) of performing a condensation reaction is performed.
<14> In the step (B), both the reactive monomer capable of reacting with the raw material monomer of the polyester resin portion and the raw material monomer of the vinyl resin portion together with the raw material monomer of the vinyl resin are subjected to an addition polymerization reaction. > The production method described.
<15> The method for producing a binder resin composition for toner according to <13> or <14>, wherein the tin catalyst is a tin (II) compound having no Sn-C bond.
<16> The method for producing a binder resin composition for toner according to any one of <13> to <15>, wherein the rare earth catalyst is a sulfonate of a rare earth element.

[Softening point of resin and resin composition (Tm)]
Using a flow tester “CFT-500D” (Shimadzu Corporation), a 1 g sample is heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa is applied by a plunger and extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. . The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening point.

[Glass transition temperature (Tg) of resin and resin composition]
Using a differential scanning calorimeter “DSC210” (manufactured by Seiko Denshi Kogyo Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, heated up to 200 ° C., and from that temperature to 0 ° C. at a rate of 10 ° C./min Cooling. Next, the sample is heated at a heating rate of 10 ° C / min, and the temperature at the intersection of the base line extension below the maximum temperature of the endothermic peak and the tangent indicating the maximum slope from the peak rise to the peak apex is obtained. The glass transition temperature is assumed.

(Acid value (AV) of resin and resin composition)
Measured according to the method of JIS K0070. However, only the measurement solvent is changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Hydroxyl value of the resin]
Measured according to the method of JIS K0070.

[Number average molecular weight of resin]
The molecular weight distribution is measured by the gel permeation chromatography (GPC) method according to the following method to determine the number average molecular weight.
(1) Preparation of sample solution Dissolve the sample in tetrahydrofuran at 25 ° C so that the concentration is 0.5 g / 100 ml. Next, this solution is filtered using a fluororesin filter “DISMIC-25JP” (manufactured by ADVANTEC) having a pore size of 0.2 μm to remove insoluble components to obtain a sample solution.
(2) Molecular weight measurement Using the following measuring device and analytical column, tetrahydrofuran is flowed as an eluent at a flow rate of 1 ml / min, and the column is stabilized in a constant temperature bath at 40 ° C. Measurement is performed by injecting 100 μl of the sample solution. The molecular weight of the sample is calculated based on a calibration curve prepared in advance. At this time, several types of monodisperse polystyrene (A-500 (5.0 × 10 ² ), A-1000 (1.01 × 10 ³ ), A-2500 (2.63 × 10 ³ ), A- 5000 (5.97 × 10 ³ ), F-1 (1.02 × 10 ⁴ ), F-2 (1.81 × 10 ⁴ ), F-4 (3.97 × 10 ⁴ ), F-10 (9.64 × 10 ⁴ ), F- 20 (1.90 × 10 ⁵ ), F-40 (4.27 × 10 ⁵ ), F-80 (7.06 × 10 ⁵ ), F-128 (1.09 × 10 ⁶ )) prepared as standard samples are used.
Measuring device: HLC-8220GPC (manufactured by Tosoh Corporation)
Analytical column: GMHXL + G3000HXL (manufactured by Tosoh Corporation)

[Melting point of release agent]
Using a differential scanning calorimeter “DSC210” (manufactured by Seiko Denshi Kogyo Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, heated up to 200 ° C., and from that temperature to 0 ° C. at a rate of 10 ° C./min Cooling. Next, the sample is heated at a heating rate of 10 ° C./min, and the maximum peak temperature of the heat of fusion is taken as the melting point.

[Volume average particle diameter of external additive]
The average particle diameter refers to the number average particle diameter and refers to the average value of the particle diameters of 500 particles measured from a scanning electron microscope (SEM) photograph of the external additive. When there is a major axis and a minor axis, the major axis is indicated.

[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) 5% electrolyte dispersion condition: 10 mg of measurement sample is added to 5 ml of dispersion, and dispersed for 1 minute with an ultrasonic disperser. Then, 25 ml of the electrolytic solution is added, and further dispersed with an ultrasonic disperser for 1 minute.
Measurement conditions: Add 100 ml of electrolyte and dispersion in a beaker, measure 30,000 particles at a concentration that can measure the particle size of 30,000 particles in 20 seconds, and determine the volume-median particle size ( determine the D _50).

[Production of cyclic polyester (A)]
Production Example 1 (Production of cyclic polyesters A-1 to A-4)
The raw material monomers and esterification catalyst excluding fumaric acid shown in Table 1 were put into a 10 liter four-necked flask equipped with a thermometer, a stainless steel stirring bar, a flow-down condenser and a nitrogen inlet tube, and a mantle heater in a nitrogen atmosphere In this, after raising the temperature to 235 ° C., the reaction was carried out at 235 ° C. for 10 hours. Thereafter, the mixture was cooled to 180 ° C., and a radical polymerization inhibitor and fumaric acid were mixed. Thereafter, the temperature was raised to 245 ° C. over 6 hours, and the reaction was carried out at 245 ° C. for 5 hours. Thereafter, the reaction mixture was cooled to 25 ° C. to obtain a reaction mixture. Thereafter, 20 g of the reaction mixture was dissolved in 50 g of dichloromethane, and 100 g of a 0.6N aqueous ammonia solution was added and shaken, followed by liquid separation to extract unreacted monomers and the like in the aqueous phase. After repeating this operation three times, ion-exchanged water was added and shaken to obtain a dichloromethane solution. Thereafter, the dichloromethane solution was condensed and dried by a rotary evaporator to obtain a powdered polyester. The acid value and hydroxyl value of this polyester are both 0, indicating that it is a cyclic compound having no end group.

Production Example 2 (Production of cyclic polyesters A-5 and A-6)
The raw material monomer and esterification catalyst shown in Table 1 were put into a 10-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen introduction tube, and 235 in a mantle heater in a nitrogen atmosphere. After raising the temperature to ° C, the reaction was carried out at 235 ° C for 10 hours. Thereafter, the temperature was raised to 245 ° C. over 2 hours, and the reaction was carried out at 245 ° C. for 5 hours. Thereafter, the reaction mixture was cooled to 25 ° C. to obtain a reaction mixture. Thereafter, 20 g of the reaction mixture was dissolved in 50 g of dichloromethane, and 100 g of a 0.6N aqueous ammonia solution was added and shaken, followed by liquid separation to extract unreacted monomers and the like in the aqueous phase. After repeating this operation three times, ion-exchanged water was added and shaken to obtain a dichloromethane solution. Thereafter, the dichloromethane solution was condensed and dried by a rotary evaporator to obtain a powdered polyester. The acid value and hydroxyl value of this polyester are both 0, indicating that it is a cyclic compound having no end group.

[Production of composite resin (B)]
Production Example 3 (Production of composite resins B-1 to B-4 and B-6 to B-9)
The raw material monomer of the polyester resin other than fumaric acid shown in Tables 2 and 3, esterification catalyst and pyrogallol compound were added to a 10 liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen inlet tube. The mixture was heated in a mantle heater in a nitrogen atmosphere to 235 ° C. over 2 hours. After confirming that the reaction rate reached 95% or higher at 235 ° C, it was cooled to 160 ° C, and the mixed solution of vinyl resin raw material monomers, both reactive monomers and radical polymerization initiator shown in Tables 2 and 3 Was added dropwise over 1 hour. Then, after maintaining at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C., further reacted for 1 hour under a reduced pressure of 8 kPa, and then cooled to 180 ° C. Thereafter, a radical polymerization inhibitor and fumaric acid were added, and the temperature was raised to 210 ° C. over 2 hours. Then, after reacting at 210 ° C. for 1 hour, the reaction was conducted at 40 kPa until the softening points shown in Tables 2 and 3 were reached, and composite resins B-1 to B-4 and B-6 to B-9 were obtained. It was. The reaction rate in the present invention refers to a value of product reaction water amount (mol) / theoretical product water amount (mol) × 100.

Production Example 10 (Production of composite resin B-5)
Place in a 10-liter four-necked flask equipped with BPA-PO, thermometer, stainless stir bar, flow-down condenser and nitrogen inlet tube shown in Table 2 and heat up to 160 ° C. Vinyl resin shown in Table 2 A mixed solution of the raw material monomer, amphoteric monomer and radical polymerization initiator was added dropwise over 1 hour. Thereafter, after maintaining at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C. and further reacted for 1 hour under reduced pressure of 8 kPa, and then terephthalic acid, esterification catalyst and esterification cocatalyst were added at 200 ° C., 235 The temperature was raised to 1 ° C. over 1 hour. Then, after reacting at 235 ° C. for 5 hours, the reaction was performed at 40 kPa until the softening point shown in Table 2 was reached, to obtain composite resin B-5.

[Production of binder resin composition for toner]
Example 1 (Production of binder resin 1)
A 10-liter four-necked flask equipped with a raw material monomer of a polyester resin other than fumaric acid shown in Table 4, an esterification catalyst 1 and an esterification cocatalyst, equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser, and a nitrogen introduction tube And heated up to 235 ° C. over 2 hours in a mantle heater in a nitrogen atmosphere. Thereafter, it was confirmed that the reaction rate reached 95% or more at 235 ° C., cooled to 160 ° C., and a mixed solution of the raw material monomer of vinyl resin, the bireactive monomer and the radical polymerization initiator shown in Table 4 was 1 It was added dropwise over time. Then, after maintaining at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C., further reacted for 1 hour under a reduced pressure of 8 kPa, and then cooled to 180 ° C. Thereafter, a radical polymerization inhibitor and fumaric acid were added, and the temperature was raised to 210 ° C. over 2 hours. Thereafter, the reaction was carried out at 210 ° C. and 40 kPa for 1 hour, and it was confirmed that the reaction rate reached 90%. Then, after returning to normal pressure with nitrogen, the esterification catalyst 2 was added at 210 ° C. Thereafter, the reaction was carried out at normal pressure and 235 ° C. for 3 hours. The obtained resin was confirmed to contain 0.5% by mass of cyclic polyester by LC-MS. Table 4 shows the physical properties. The reaction rate in the present invention refers to a value of product reaction water amount (mol) / theoretical product water amount (mol) × 100.

[Manufacture of toner for developing electrostatic image]
Examples 2 to 15 and Comparative Examples 1 to 3
20 parts by mass of the composite resin (B) and cyclic polyester (A) shown in Table 5 in the mass ratio shown in Table 5 and 0.2 parts by mass of the negatively chargeable charge control agent “Bontron E-81” (manufactured by Orient Chemical Co., Ltd.) , 1 part by weight of coloring agent “Regal 330R” (Cabot, carbon black), 0.4 part by weight of release agent “Mitsui High Wax NP055” (manufactured by Mitsui Chemicals, polypropylene wax, melting point: 125 ° C.) After sufficiently mixing with a mixer, the mixture was melt-kneaded at a roll rotation speed of 200 r / min and a heating temperature in the roll of 80 ° C. using a co-rotating twin screw extruder. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized with a jet mill and classified to obtain toner particles having a volume median particle size (D ₅₀ ) of 8 μm.

  To 100 parts by mass of the toner particles obtained, 1.0 part by mass of hydrophobic silica “NAX-50” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: HMDS, average particle size: 30 nm) is added and mixed with a Henschel mixer. Thus, a toner was obtained.

Example 16
20 parts by weight of binder resin 1, 0.2 parts by weight of negatively chargeable charge control agent “Bontron E-81” (manufactured by Orient Chemical Co., Ltd.), 1 part by weight of colorant “Regal 330R” (manufactured by Cabot, carbon black), And 0.4 part by weight of release agent “Mitsui High Wax NP055” (manufactured by Mitsui Chemicals, polypropylene wax, melting point: 125 ° C.) was thoroughly mixed with a Henschel mixer, and then the rotational speed of the roll using a co-rotating twin screw extruder It was melt-kneaded at a heating temperature of 80 ° C. in a roll at 200 r / min. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized with a jet mill and classified to obtain toner particles having a volume median particle size (D ₅₀ ) of 8 μm.

  To 100 parts by mass of the toner particles obtained, 1.0 part by mass of hydrophobic silica “NAX-50” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: HMDS, average particle size: 30 nm) is added and mixed with a Henschel mixer. Thus, a toner was obtained.

Test Example 1 [Heat resistant storage stability of toner]
4 g of toner was placed in a 20 mL container (diameter of about 3 cm) and left for 72 hours in an environment of 55 ° C. and 50% humidity. The degree of toner aggregation was visually observed every 12 hours, and the heat resistant storage stability was evaluated according to the following evaluation criteria. The results are shown in Table 5.

〔Evaluation criteria〕
A: No aggregation is observed even after 72 hours.
B: Aggregation is not observed after 60 hours, but aggregation is observed after 72 hours.
C: Aggregation is not observed after 48 hours, but aggregation is observed after 60 hours.
D: Aggregation is not observed after 36 hours, but aggregation is observed after 48 hours.
E: Aggregation is not observed after 24 hours, but aggregation is observed after 36 hours.
F: Aggregation is observed within 24 hours.

Test Example 2 [Colorability of toner]
A toner was mounted on a copying machine “AR-505” (trade name, manufactured by Sharp Corporation), and an image was printed without fixing (printing area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm ² ). The unfixed image was fixed at 200 ° C. and 50 mm / sec using a fixing machine which was removed from the copier “CX7700” (trade name, manufactured by Sharp Corporation) and temperature and speed could be controlled. As the fixing paper, “CopyBondSF-70NA” (trade name, manufactured by Sharp Corporation, 75 g / m ² ) was used. The obtained image is placed on 20 sheets of A4 copy paper (RPCA4R), and L ^* a ^* b ^* is measured with a color difference meter (manufactured by Gretag), and √ ((a ^* ) ² + ( b ^* ) The value of ² ) was calculated to evaluate the color reproducibility. The results are shown in Table 5. A larger color reproducibility value indicates better color developability.

  From the above results, it can be seen that the toners of the examples are all excellent in color developability and heat resistant storage stability as compared with the toner of the comparative example.

  The binder resin composition for a polyester-based toner of the present invention is suitably used for a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.

Claims (10)

  A binder resin composition for a polyester toner comprising a cyclic polyester (A) and a composite resin (B), wherein the carboxylic acid component of the cyclic polyester (A) is an aliphatic dicarboxylic acid having 2 to 6 carbon atoms. An acid compound is contained, and the composite resin (B) is composed of a polyester resin portion and a vinyl resin portion, and the mass ratio of the cyclic polyester (A) and the composite resin (B) in the binder resin composition (cyclic polyester ( A binder resin composition for a polyester-based toner, wherein A) / composite resin (B)) is 0.01 / 99.99 to 4.0 / 96.0.   The binder resin composition for a polyester-based toner according to claim 1, wherein the content of the aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms is 25 to 85 mol% in the carboxylic acid component of the cyclic polyester (A).   The binder resin composition for a polyester-based toner according to claim 1 or 2, wherein the carboxylic acid component of the cyclic polyester (A) further contains an aromatic dicarboxylic acid compound.   Molar ratio of aromatic dicarboxylic acid compound to aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the carboxylic acid component of cyclic polyester (A) (aromatic dicarboxylic acid compound / aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms) The binder resin composition for a polyester-based toner according to claim 3, wherein is from 75/25 to 15/85.   The composite resin (B) includes a raw material monomer for the polyester resin part, a raw material monomer for the vinyl resin part, and a bireactive monomer that can react with both the raw material monomer for the polyester resin part and the raw material monomer for the vinyl resin part. The binder resin composition for a polyester toner according to any one of claims 1 to 4, which is a resin obtained by polymerization.   The polyester toner binder according to claim 1, wherein a mass ratio of the polyester resin portion to the vinyl resin portion (polyester resin portion / vinyl resin portion) in the composite resin is 50/50 to 95/5. Resin composition.   The binder resin composition for a polyester-based toner according to any one of claims 1 to 6, wherein the cyclic polyester (A) has an acid value of 0.1 mgKOH / g or less and a hydroxyl value of 0.1 mgKOH / g or less.   An electrostatic image developing toner comprising the polyester resin binder resin composition according to claim 1. It is a manufacturing method of the binder resin composition for polyester toners in any one of Claims 1-7,
(i) After the step (A) of performing a polycondensation reaction with a raw material monomer of a polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst, A method of performing the step (B) of performing an addition polymerization reaction with a raw material monomer, or
(ii) After the step (B) of the addition polymerization reaction with the raw material monomer of the vinyl resin portion, the raw material of the polyester resin portion containing an aliphatic dicarboxylic acid compound having 2 to 6 carbon atoms in the presence of a titanium catalyst or a tin catalyst A resin having a polycondensation reaction rate of 70% or more and less than 100% is obtained by the method of performing the step (A) of performing a polycondensation reaction with a monomer, and further, a polycondensation reaction is performed at 200 to 250 ° C. in the presence of a rare earth catalyst. A method for producing a binder resin composition for a polyester-based toner, wherein the step (C) of performing a condensation reaction is performed.   The production according to claim 9, wherein in the step (B), both the reactive monomer capable of reacting with the raw material monomer of the polyester resin portion and the raw material monomer of the vinyl resin portion together with the raw material monomer of the vinyl resin are subjected to an addition polymerization reaction. Method.