JP2019095515A - Binder resin composition for toner - Google Patents

Abstract

To provide a binder resin composition for toner excellent in low temperature fixability, durability and charge stability in high temperature and high humidity, a method for producing the same, and an electrophotographic toner containing the binder resin composition.SOLUTION: There are provided a binder resin composition for toner that contains a composite resin in which a polyester-based resin that is a polycondensation product of an alcohol component containing 40 mol% or more and 100 mol% or less of aliphatic diol having two hydroxyl groups bonded to primary hydrogen atoms, a carboxylic acid component and polyethylene terephthalate, and a styrene-based resin that is an addition polymer of a raw material monomer containing a styrene-based compound are chemically bonded through one or two or more bireactive monomers selected from acrylate and methacrylate; a method for producing the same; and an electrophotographic toner containing the binder resin composition.SELECTED DRAWING: None

Description

  The present invention relates to a binder resin composition for toner used for developing a latent image formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method, etc., a method for producing the same, and the binder resin composition. The present invention relates to an electrophotographic toner contained therein.

  In recent years, there has been a demand for a binder resin for toners that can be fixed at a lower temperature, in response to demands for higher speed and smaller size of the apparatus. Styrene resins and polyester resins are generally used as the binder resin for toners, but polyester resins are considered to be preferable from the viewpoint of low-temperature fixability. It is known that lowering the softening point and glass transition temperature of the resin is effective in improving low-temperature fixability, but on the other hand, it is still sufficiently satisfactory in terms of chargeability under high temperature and high humidity. It is not a level.

  Patent Document 1 describes a binder resin composition for toner containing a crystalline polyester and an amorphous composite resin, wherein the crystalline polyester comprises an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms. It is a crystalline polyester obtained by polycondensation of a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 4 to 10 carbon atoms, and the amorphous composite resin is a raw material monomer of the polyester resin portion, and a vinyl resin Obtained by polymerizing a portion of the raw material monomer and a bireactive monomer capable of reacting with either of the raw material monomer of the polyester resin portion and the raw material monomer of the vinyl resin portion, and the raw material monomer of the polyester resin portion is a secondary An alcohol component containing an aliphatic diol having a hydroxyl group bonded to a carbon atom and a carboxylic acid component; Amounts, the alcohol component 100 moles of the polyester resin moiety is a 1-5 moles, for toner binder resin composition is disclosed.

  Patent Document 2 contains a polyester resin which is a polycondensate of polyethylene terephthalate, a carboxylic acid component, and an alcohol component, and the polyethylene terephthalate contains polyethylene terephthalate (PET) having an IV value of 0.40 or more and 0.75 or less. Disclosed is a binder resin composition for toner, wherein the alcohol component contains an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 2 to 4 carbon atoms in an amount of 40 to 100 mol%. Further, as the binder resin composition, a composite resin containing a polyester resin using the above-mentioned PET and a styrene resin is also described.

JP, 2015-169728, A JP 2017-90889 A

  The so-called non-bis-based resins in which the alkylene oxide adduct of bisphenol A is not used as the raw material monomer are so high in hydrophilicity that the charge stability under high temperature and high humidity is low. Therefore, complexation with a hydrophobic styrenic resin has been conventionally studied. However, in the prior art, since the hydrophilicity / hydrophobicity of the non-bis resin and the styrenic resin are different, the complexing reaction is not sufficient. The reason is presumed to be that the complexing of the styrenic resin with the raw material monomer does not proceed sufficiently because the bireactive monomer conventionally used is relatively hydrophilic. Further, further improvement is required for durability.

  The present invention relates to a binder resin composition for toners which is excellent in low temperature fixability, durability, and charge stability under high temperature and high humidity, a method for producing the same, and a toner for electrophotography comprising the binder resin composition. .

The present invention
[1] Polyester-based resin which is a polycondensation reaction product of an alcohol component, a carboxylic acid component and a polyethylene terephthalate containing 40 mol% or more and 100 mol% or less of an aliphatic diol having two hydroxyl groups bonded to primary carbon atoms And a styrenic resin, which is an addition polymer of a raw material monomer containing a styrenic compound, chemically bonded via one or two or more types of both reactive monomers selected from acrylic acid ester and methacrylic acid ester Binder resin composition for toner containing composite resin,
[2] After the step of addition-polymerizing a raw material monomer containing a styrene compound in the presence of one or two or more types of both reactive monomers selected from acrylic acid ester and methacrylic acid ester, to primary carbon atom A method for producing a binder resin composition for toner, comprising the step of polycondensing an alcohol component containing 40 mol% to 100 mol% of an aliphatic diol having two bonded hydroxyl groups, a carboxylic acid component and polyethylene terephthalate, And [3] a toner for electrophotography, which comprises the binder resin composition for toner according to the above [1].

  The toner for electrophotography containing the binder resin composition of the present invention exhibits excellent effects in low-temperature fixability, durability, and charge stability under high temperature and high humidity.

  The toner for electrophotography of the present invention (hereinafter, also simply referred to as toner) contains, as a binder resin, an aliphatic diol having two hydroxyl groups bonded to primary carbon atoms in an amount of 40 to 100 mol%. A polyester resin which is a polycondensation product of an alcohol component, a carboxylic acid component and polyethylene terephthalate and a styrene resin which is an addition polymer of a raw material monomer containing a styrene compound are selected from acrylic esters and methacrylic esters. A resin composition containing a composite resin chemically bonded via one or more bireactive monomers. Here, the dual reactive monomer refers to a compound having an unsaturated double bond which can be copolymerized with an addition polymerization type monomer, and having a functional group capable of reacting with a hydroxyl group or a carboxyl group.

  The reason why the resin composition of the present invention is excellent in low-temperature fixability, durability, and charge stability under high temperature and high humidity is not clear, but is considered as follows.

  Polyester-based resins obtained using aliphatic diols tend to have higher ester values than when aromatic polyhydric alcohols such as alkylene oxides of bisphenol A, which are generally used, are used. It is considered that the low temperature fixability is excellent from the viewpoint of affinity with paper. Further, since the alcohol component contains an aliphatic diol having two hydroxyl groups bonded to a predetermined amount or more of primary carbon atoms, in addition to the high reactivity of the alcohol component, polyethylene terephthalate which is a polymer resin is used as a raw material Since it is used, it is thought that low molecular weight components, such as a monomer and an oligomer, can be reduced, and it is thought that durability is favorable. Furthermore, while hydrophilic acrylic acid has conventionally been used as a dual reactive monomer, in the present invention, both hydrophobic acrylic acid esters and / or methacrylic acid esters are used as a dual reactive monomer. The reaction between the reactive monomer and the raw material monomer of the hydrophobic styrenic resin was good, and the compounding reaction proceeded sufficiently to enable uniform resin synthesis. As a result, it is considered that the hydrophilic polyester-based resin which is not complexed is reduced, and the charging stability under high temperature and high humidity is greatly improved.

  The polyester-based resin is a polycondensation reaction product of an alcohol component, a carboxylic acid component and polyethylene terephthalate.

  The alcohol component contains an aliphatic diol having two hydroxyl groups bonded to a primary carbon atom.

  Examples of aliphatic diols having two hydroxyl groups bonded to primary carbon atoms include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6. -Hexanediol etc. are mentioned, Among these, neopentyl glycol or 1,4-butanediol is preferable, and neopentyl glycol is more preferable.

  The content of neopentyl glycol in the aliphatic diol having two hydroxyl groups bonded to primary carbon atoms is preferably 1 mol% or more, more preferably 5 mol from the viewpoint of charge stability under high temperature and high humidity. % Or more, more preferably 30 mol% or more, further preferably 50 mol% or more, further preferably 70 mol% or more.

  The carbon number of the aliphatic diol having two hydroxyl groups bonded to the primary carbon atom is preferably 2 or more, more preferably 3 or more, still more preferably 4 or more, and preferably 8 or less, more preferably 6 or less. The carbon chain of the aliphatic diol may be linear or branched, but is preferably branched from the viewpoint of charge stability under high temperature and high humidity.

  The content of the aliphatic diol having two hydroxyl groups bonded to the primary carbon atom is 40 mol% or more, preferably 50 mol%, from the viewpoint of charge stability under high temperature and high humidity in the alcohol component. The content is more preferably 60 mol% or more and 100 mol% or less, and preferably 90 mol% or less, more preferably 80 mol% or less from the viewpoint of low-temperature fixability.

  Further, the alcohol component has, in addition to an aliphatic diol having two hydroxyl groups bonded to a primary carbon atom, a hydroxyl group bonded to a secondary carbon atom from the viewpoint of charge stability under high temperature and high humidity. It is preferable to contain an aliphatic diol.

  As an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom, 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentane Diol, 1,3-pentanediol, 2,3-pentanediol, 2,4-pentanediol etc. are mentioned, Among these, 1,2-propanediol or 2,3-butanediol is preferable, More preferred is 2-propanediol.

  The carbon number of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferably 3 or more, and preferably 6 or less, more preferably 4 or less.

  The content of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferably 5 mol% or more, more preferably 10 mol% or more in the alcohol component, from the viewpoint of low-temperature fixability. From the viewpoint of charge stability under high humidity, it is 60 mol% or less, preferably 50 mol% or less, more preferably 40 mol% or less.

  In the alcohol component, the molar ratio of an aliphatic diol having two hydroxyl groups bonded to a primary carbon atom and an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom (hydroxyl group bonded to a primary carbon atom) Aliphatic diol having two or aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferably 40/60 or more, more preferably 50/60 from the viewpoint of charge stability under high temperature and high humidity. It is 50 or more, more preferably 60/40 or more, and preferably 95/5 or less, more preferably 90/10 or less from the viewpoint of low-temperature fixability.

  As other alcohol components, aromatic diols such as alkylene oxide adducts of bisphenol A, aliphatic diols other than the above, trivalent or higher alcohols such as glycerin, and the like can be mentioned as long as the effects of the present invention are not impaired.

  On the other hand, as a carboxylic acid component, as a bivalent carboxylic acid type compound, an aromatic dicarboxylic acid type compound is preferred from a durable viewpoint. In addition, from the viewpoint of low temperature fixability, aliphatic dicarboxylic acid compounds are preferable. In the present invention, carboxylic acid compounds include not only free acids but also anhydrides which are decomposed during the reaction to form acids, and alkyl esters having 1 or more and 3 or less carbon atoms.

  Examples of aromatic dicarboxylic acid compounds include phthalic acid, isophthalic acid and terephthalic acid; anhydrides of these acids and alkyl esters of those acids having 1 or more and 3 or less carbon atoms. Terephthalic acid or isophthalic acid is preferred, and terephthalic acid is more preferred.

  The content of the aromatic dicarboxylic acid-based compound is preferably 30 mol% or more, more preferably 40 mol% or more in the carboxylic acid component from the viewpoint of toner durability, and from the viewpoint of low-temperature fixability Preferably it is 80 mol% or less.

  On the other hand, the carbon number of the aliphatic dicarboxylic acid compound is preferably 4 or more, and preferably 14 or less, more preferably 12 or less from the viewpoint of availability. As aliphatic dicarboxylic acid compounds, succinic acid (carbon number: 4), fumaric acid (carbon number: 4), glutaric acid (carbon number: 5), adipic acid (carbon number: 6), suberic acid (carbon number) : 8), azelaic acid (carbon number: 9), sebacic acid (carbon number: 10), dodecane diacid (carbon number: 12), tetradecane diacid (carbon number: 14), alkyl or alkenyl group in side chain Succinic acid, anhydrides of these acids, alkyl esters having 1 to 3 carbon atoms thereof, and the like. In addition, carbon number of the alkyl group of an alkyl ester part is not included in carbon number of an aliphatic dicarboxylic acid type compound.

  The content of the aliphatic dicarboxylic acid-based compound is preferably 5 mol% or more, more preferably 10 mol% or more in the carboxylic acid component from the viewpoint of low-temperature fixability, and preferably from the viewpoint of durability. It is 50 mol% or less, more preferably 40 mol% or less, still more preferably 30 mol% or less.

  Moreover, it is preferable that the carboxylic acid component contains the trivalent or more aromatic carboxylic acid type compound from a durable viewpoint.

  Examples of trivalent or higher aromatic carboxylic acid compounds include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid and their acid anhydrides, carbon number 1 or more and 3 or less alkyl ester etc. are mentioned, Among these, a trimellitic acid type compound is preferable.

  The content of the trivalent or higher aromatic carboxylic acid compound is preferably 5 mol or more, more preferably 10 mol or more, and still more preferably 15 mol or more from the viewpoint of improving the softening point with respect to 100 mol of the alcohol component. And from the viewpoint of lowering the softening point and low temperature fixability, it is preferably 30 mol or less, more preferably 25 mol or less, and still more preferably 20 mol or less.

  A monohydric alcohol may be suitably contained in the alcohol component, and a monobasic carboxylic acid compound may be suitably contained in the carboxylic acid component from the viewpoint of molecular weight adjustment and the like.

  The equivalent molar ratio (COOH group / OH group) of the carboxylic acid component to the alcohol component in the polyester resin is preferably 0.7 or more, more preferably 0.8 or more, from the viewpoint of adjusting the softening point of the resin, and preferably Is 1.5 or less, more preferably 1.1 or less.

  As polyethylene terephthalate (PET), one produced according to a conventional method by polycondensation of ethylene glycol with terephthalic acid, dimethyl terephthalate or the like can be used.

The PET reacts with the alcohol component and the carboxylic acid component in the polycondensation reaction and is incorporated into the structure of the resin, which may be accompanied by the depolymerization of the PET.
Therefore, in the present invention, PET is preferably a PET having a relatively low IV value, that is, a low molecular weight, as compared with conventionally used PET. In the present invention, the depolymerization of PET proceeds more uniformly by introducing a low IV (low molecular weight) PET into the polyester resin. As a result, since it can disperse | distribute uniformly, leaving a PET frame with high polarity in a polymer, it is guessed that durability of a toner improves more than the conventional PET introduce | transducing resin.

  From the above point of view, the IV value of PET is preferably 0.40 or more, more preferably 0.45 or more, still more preferably 0.50 or more, still more preferably 0.55 or more, and from the viewpoint of low temperature fixing and uniformization of depolymerization. Preferably it is 0.80 or less, More preferably, it is 0.75 or less, More preferably, it is 0.70 or less, More preferably, it is 0.65 or less, More preferably, it is 0.60 or less. The IV value is an intrinsic viscosity and is an index of molecular weight. The IV value of PET can be adjusted by the polycondensation time or the like.

  Commercial products of PET having an IV value of 0.40 or more and 0.80 or less include RAMAPET L1 (manufactured by Indorama Ventures, IV value: 0.60), RAMAPET N2G (manufactured by Indorama Ventures, IV value: 0.75), TRN-NTJ (Teijin (stock IV): 0.53), TRN-RTJC (manufactured by Teijin Limited, IV: 0.64), and the like.

  PET is preferably a terephthalic acid-ethylene glycol unit (Mw: 192) from the viewpoint of durability and charge stability under high temperature and high humidity with respect to a total of 100 moles of a carboxylic acid component and an alcohol component. Is preferably 5 moles or more, more preferably 10 moles or more, and still more preferably 20 moles or more, and preferably 90 moles or less, more preferably 80 moles or less from the viewpoint of low temperature fixability and charge stability under high temperature and high humidity. It is preferable to polycondense with the carboxylic acid component and the alcohol component in an amount of not more than mol, more preferably not more than 70 mol, further preferably not more than 60 mol.

  The polycondensation reaction of the alcohol component, the carboxylic acid component and the PET is carried out, for example, in an inert gas atmosphere, preferably in the presence of an esterification catalyst, and, if necessary, an esterification cocatalyst, a polymerization inhibitor, etc. It can be carried out in the presence, preferably at a temperature of about 180 ° C. to 250 ° C. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropylate bis triethanolaminate. Among these, tin compounds such as tin (II) 2-ethylhexanoate are preferred. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1.5 parts by mass, based on 100 parts by mass of the total of the alcohol component, the carboxylic acid component, and PET. It is preferably at most 1.0 part by mass, and more preferably at most 1.0 part by mass. Examples of the esterification promoter include gallic acid and the like. The amount of the esterification promoter used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass with respect to 100 parts by mass of the total amount of the alcohol component, the carboxylic acid component, and PET. It is not more than mass part, more preferably not more than 0.1 mass part. Examples of the polymerization inhibitor include tert-butyl catechol and the like. The amount of the polymerization inhibitor used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass, based on 100 parts by mass of the total amount of the alcohol component, the carboxylic acid component, and PET. It is not more than part, preferably not more than 0.1 part by weight.

  The raw material monomer of the styrenic resin contains at least a styrene compound. As a styrene compound, styrene derivatives, such as alpha methyl styrene and vinyl toluene other than styrene, etc. are mentioned, and styrene is preferred.

  The content of the styrene compound is preferably 70% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more in the raw material monomer of the styrene resin from the viewpoint of charge stability under high temperature and high humidity. More preferably, it is 100 mass%.

  Ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; halovinyls such as vinyl acetate; and the like Vinyl esters; ethylenic monocarboxylic acid esters such as dimethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone etc. It can be mentioned.

  The addition polymerization reaction of a raw material monomer of a styrenic resin can be carried out by a conventional method, for example, in the presence of a polymerization initiator such as dicumyl peroxide, a crosslinking agent, etc. in the presence or absence of an organic solvent. The temperature condition is preferably 110 ° C. or more, more preferably 140 ° C. or more, and preferably 200 ° C. or less, more preferably 170 ° C. or less.

  When an organic solvent is used in the addition polymerization reaction, xylene, toluene, methyl ethyl ketone, acetone or the like can be used. The amount of the organic solvent used is preferably 10 parts by mass to 50 parts by mass with respect to 100 parts by mass of the raw material monomer of the addition polymerization resin component.

  The bireactive monomer used in the present invention is one or more selected from acrylic acid esters and methacrylic acid esters.

  The (meth) acrylic acid ester is preferably a (meth) acrylic acid alkyl ester from the viewpoint of reactivity to transesterification, and the carbon number of the alkyl group is preferably 2 or more, more preferably 3 or more. And preferably 6 or less, more preferably 4 or less. In addition, even if the number of carbon atoms of the alkyl group is 7 or more, the alcohol residue is bulky and transesterification like an alkyl ester having a branched chain or an ester having a cyclic hydrocarbon group even if it is not an alkyl ester. If it is an ester which has a structure which is easy to detach | desorb, it can be used as a bi-reactive monomer.

  Specific examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate ( Examples thereof include: (meth) acrylic acid (iso or tertiary) butyl, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic acid (iso) octyl and the like. In the present specification, “(meth) acrylic acid” indicates acrylic acid, methacrylic acid, or both of them. Also, “(iso or tertiary)”, “(iso)” are meant to include both the case where these groups exist and the case where they do not exist, and when these groups do not exist, Indicates that it is normal.

  In the present invention, the acrylic acid ester is preferably an acrylic acid alkyl ester having 2 to 6 carbon atoms in the alkyl group, more preferably butyl acrylate, and the methacrylic acid ester preferably has a carbon number of the alkyl group It is a methacrylic acid alkyl ester which is 2 or more and 6 or less, more preferably butyl methacrylate.

  The mass ratio of the bireactive monomer to the raw material monomer of the styrenic resin (bireactive monomer / raw material monomer of styrenic resin) is preferably 5/95 or more, more preferably from the viewpoint of charge stability under high temperature and high humidity. The ratio is preferably 10/90 or more, more preferably 20/80 or more, still more preferably 25/75 or more, still more preferably 30/70 or more, and from the viewpoint of low-temperature fixability, preferably 95/5 or less, more preferably It is preferably 70/30 or less, more preferably 60/40 or less, further preferably 50/50 or less, and further preferably 40/60 or less.

In the present invention, the composite resin is
Step (A) of obtaining a polyester resin by polycondensing an alcohol component containing an aliphatic diol having two hydroxyl groups bonded to primary carbon atoms with a carboxylic acid component and PET, and styrene containing a styrene compound Step (B) of obtaining a styrene resin by addition polymerization of a raw material monomer of the resin based resin
It is preferable to obtain by a method including The polycondensation reaction of the alcohol component, the carboxylic acid component, and the PET of the polyester resin and the addition polymerization reaction of the raw material monomer of the styrene resin may be performed sequentially or simultaneously, but in the present invention, the low temperature fixability From the viewpoint of the step (A), the step (A) is preferably performed after the step (B) rather than the method of performing the step (B).

  That is, in the resin composition of the present invention, after the step of addition-polymerizing a raw material monomer containing a styrene compound in the presence of one or two or more bireactive monomers selected from acrylic acid ester and methacrylic acid ester Preferably obtained by a method comprising the step of polycondensing PET with an alcohol component containing an aliphatic diol having two hydroxyl groups bonded to primary carbon atoms and a carboxylic acid component, and a raw material monomer containing a styrene compound 1 or 2 selected from an alcohol component containing an aliphatic diol having two hydroxyl groups bonded to a primary carbon atom, a carboxylic acid component, PET, and an acrylic ester and a methacrylic ester in the step of addition polymerization It is more preferred to carry out in the presence of species or more of both reactive monomers. Thus, in the method in which the polycondensation reaction of the alcohol component, the carboxylic acid component and the PET is carried out before the addition polymerization reaction, the amount of alcohol component used for the transesterification reaction decreases, while the bireactive monomer and the aliphatic diol are reduced. It is believed that the terminal hydroxyl group of the is more efficiently transesterified to form a crosslinked structure.

  In addition, when using an unsaturated alcohol or an unsaturated carboxylic acid compound as a raw material monomer of polyester-based resin when performing a process (B) after a process (A), unsaturated alcohol or unsaturatedity is added to an addition polymerization reaction material. It is preferable from the viewpoint of low-temperature fixability to add a carboxylic acid compound and further cause a polycondensation reaction.

  Further, in the production of the composite resin, it is preferable to use the bireactive monomer together with the raw material monomer of the styrenic resin.

  The polycondensation reaction and the addition polymerization reaction are preferably carried out in the same reaction vessel, and the polycondensation reaction is carried out in the presence of the raw material monomer for the addition polymerization resin, and the addition polymerization reaction is carried out for the raw material monomer of the polycondensation resin In the presence of

  The mass ratio of polyester resin to styrene resin in the composite resin (polyester resin / styrene resin) is preferably 95/5 or less, more preferably 90/10, from the viewpoint of charging stability under high temperature and high humidity. Or less, more preferably 85/15 or less, and from the viewpoint of low-temperature fixability, preferably 50/50 or more, more preferably 55/45 or more, still more preferably 60/40 or more, further preferably 65/35 The above, more preferably 70/30 or more. In the above calculation, the mass of the polyester resin is an amount obtained by removing the amount (calculated value) of the reaction water to be dehydrated by the polycondensation reaction from the mass of the raw material monomer of the polyester resin to be used. The amount of styrenic resin is the amount of raw material monomer of styrenic resin and does not include the amount of polymerization initiator. The amount of the bireactive monomer is included in the amount of the raw material monomer of the styrenic resin.

  The softening point of the composite resin is preferably 100 ° C. or more, more preferably 105 ° C. or more, still more preferably 110 ° C. or more, still more preferably 115 ° C. or more, from the viewpoint of durability. Preferably it is 150 degrees C or less, More preferably, it is 145 degrees C or less, More preferably, it is 140 degrees C or less, More preferably, it is 135 degrees C or less.

  The crystallinity of the resin is represented by the ratio of the softening point to the highest peak temperature of endotherm by differential scanning calorimeter, that is, the crystallinity index defined by the value of [softening point / highest peak temperature of endotherm]. The crystalline resin is a resin having a crystallinity index of 0.6 or more, preferably 0.7 or more, more preferably 0.9 or more, and 1.4 or less, preferably 1.2 or less, more preferably 1.1 or less. Is a resin having a crystallinity index of more than 1.4, preferably more than 1.5, more preferably more than 1.6, or a resin less than 0.6, preferably less than 0.5. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers, and the production conditions (eg, reaction temperature, reaction time, cooling rate) and the like. The highest endothermic peak temperature refers to the temperature of the highest end of the observed endothermic peaks. In a crystalline resin, the highest peak temperature of the endotherm is taken as the melting point.

  The glass transition temperature of the composite resin is preferably 50 ° C. or higher from the viewpoint of improving the durability of the toner, and is preferably 80 ° C. or less, more preferably 75 ° C. from the viewpoint of improving the low temperature fixability of the toner. The temperature is more preferably 70 ° C. or less. The glass transition temperature is a physical property unique to the amorphous phase.

  The acid value of the composite resin is preferably 40 mg KOH / g or less, more preferably 30 mg KOH / g or less, still more preferably 25 mg KOH / g or less, still more preferably 20 mg KOH / g or less from the viewpoint of charge stability under high temperature and high humidity. And preferably 1 mg KOH / g or more, more preferably 2 mg KOH / g or more, still more preferably 5 mg KOH / g or more.

  The hydroxyl value of the composite resin is preferably 80 mg KOH / g or less, more preferably 70 mg KOH / g or less, still more preferably 60 mg KOH / g or less, still more preferably 50 mg KOH / g or less, from the viewpoint of charge stability under high temperature and high humidity. More preferably, it is 40 mg KOH / g or less, and preferably 5 mg KOH / g or more, more preferably 10 mg KOH / g or more, and still more preferably 15 mg KOH / g or more.

  The content of the composite resin using PET is preferably 40% by mass or more, more preferably 60% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more in the binder resin composition. More preferably, it is 95 mass% or more, More preferably, it is 100 mass%.

  The resin composition of the present invention may contain a resin other than the composite resin using the PET.

  Examples of the binder resin other than polyester resin using PET include crystalline polyester resin and the like. As a crystalline polyester resin, for example, a polycondensation product of an alcohol component containing an aliphatic diol having 2 to 16 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 4 to 14 carbon atoms preferable.

  Examples of the aliphatic diol having 2 to 16 carbon atoms contained in the alcohol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and the like. , 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, neopentyl glycol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecane A diol etc. are mentioned and even if it is 1 type, 2 or more types may be used together.

  The aliphatic diol having 2 to 16 carbon atoms is preferably an α, ω-aliphatic diol having a hydroxyl group at the end of the carbon chain from the viewpoint of low-temperature fixability, and an α, ω-linear alkane More preferably, it is a diol.

  The carbon number of the aliphatic diol is 2 or more, preferably 4 or more, more preferably 6 or more from the viewpoint of low-temperature fixability, and 16 or less, preferably 14 or less, more preferably from the viewpoint of durability. It is 12 or less, more preferably 8 or less.

  The content of the aliphatic diol having 2 to 16 carbon atoms is 95 mol% or more, preferably 98 mol% or more, and more preferably 100 mol% in the alcohol component of the crystalline polyester resin from the viewpoint of low-temperature fixability. is there.

  Other alcohol components include aliphatic diols having 17 or more carbon atoms, aromatic diols such as alkylene oxide adducts of bisphenol A, and alcohols having a trivalent or higher such as sorbitol, pentaerythritol, glycerin and trimethylolpropane. .

  The aliphatic dicarboxylic acid compound having 4 to 14 carbon atoms contained in the carboxylic acid component includes succinic acid (4 carbon atoms), fumaric acid (4 carbon atoms), adipic acid (6 carbon atoms), and suberin Acid (carbon number: 8), azelaic acid (carbon number: 9), sebacic acid (carbon number: 10), dodecanedioic acid (carbon number: 12), tetradecanedioic acid (carbon number: 14), alkyl on side chain The succinic acid which has a group or an alkenyl group, the anhydride of these acids, C1-C3 alkyl ester of these acids, etc. are mentioned.

  The carbon number of the aliphatic dicarboxylic acid-based compound is 4 or more, preferably 6 or more, more preferably 8 or more from the viewpoint of low-temperature fixability, and 14 or less, preferably 12 or less from the viewpoint of durability. is there.

  The content of the aliphatic dicarboxylic acid compound having 4 to 14 carbon atoms is 95 mol% or more, preferably 98 mol% or more, more preferably from the viewpoint of low-temperature fixability in the carboxylic acid component of the crystalline polyester resin. It is 100 mol%.

  Other carboxylic acid components include aromatic dicarboxylic acid compounds such as phthalic acid, isophthalic acid and terephthalic acid, aliphatic dicarboxylic acid compounds having 15 or more carbon atoms, and trivalent or more compounds such as trimellitic acid and pyromellitic acid Examples thereof include carboxylic acid compounds, anhydrides of these acids, and alkyl esters having 1 or more and 3 or less carbon atoms.

  From the viewpoint of durability, the equivalent molar ratio (COOH group / OH group) of the carboxylic acid component and the alcohol component of the crystalline polyester resin is preferably 0.8 or more, more preferably 0.9 or more, and the low temperature fixability viewpoint Preferably, it is 1.2 or less, more preferably 1.1 or less.

  The polycondensation reaction conditions of the alcohol component, the carboxylic acid component and the PET are the same as the reaction conditions of the above-mentioned polyester resin except that the polycondensation reaction conditions are performed at a temperature of about 140 ° C. or more and 250 ° C. or less.

  The softening point of the crystalline polyester resin is preferably 50 ° C. or more, more preferably 65 ° C. or more from the viewpoint of durability, and preferably 120 ° C. or less, more preferably 110 ° C. from the viewpoint of low temperature fixability. The temperature is more preferably 100 ° C. or less, further preferably 85 ° C. or less.

  The melting point of the crystalline polyester resin is preferably 40 ° C. or more, more preferably 60 ° C. or more from the viewpoint of durability, and preferably 110 ° C. or less, more preferably 100 ° C. or less from the viewpoint of low temperature fixability. More preferably, the temperature is 80 ° C. or less.

  The acid value of the crystalline polyester resin is preferably 5 mg KOH / g or more, more preferably 8 mg KOH / g or more from the viewpoint of low-temperature fixability, and preferably from the viewpoint of charge stability under high temperature and high humidity. It is 30 mg KOH / g or less, more preferably 20 mg KOH / g or less.

  The hydroxyl value of the crystalline polyester resin is preferably 5 mg KOH / g or more, more preferably 10 mg KOH / g or more from the viewpoint of low-temperature fixability, and preferably from the viewpoint of charge stability under high temperature and high humidity. It is 40 mg KOH / g or less, more preferably 30 mg KOH / g or less.

  The mass ratio of the composite resin using PET to the crystalline polyester resin (polyester resin using PET / crystalline polyester resin) is preferably 75/25 or more, more preferably 80/20 or more from the viewpoint of durability. And more preferably 85/15 or more, and from the viewpoint of low-temperature fixability, preferably 99/1 or less, more preferably 95/5 or less.

  When the binder resin composition of the present invention contains two or more resins, a mixture of those resins may be used as a binder resin, and when producing a toner, those resins are directly used as raw materials. You may use for mixing.

  In the toner of the present invention, in addition to the binder resin (the binder resin composition of the present invention), a colorant, a release agent, a charge control agent, a magnetic powder, a flowability improver, a conductivity regulator, a fibrous substance Additives such as reinforcing fillers, antioxidants, cleanability improvers, etc. may be contained.

  As the colorant, dyes, pigments and the like used as colorants for toners can be used. For example, 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, isoindoline, disazo aero etc. may be mentioned. . In the present invention, the toner particles may be either black toner or color toner.

  The content of the colorant is preferably 1 part by mass or more, 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 image density and low temperature fixability of the toner. Preferably it is 40 parts by mass or less, more preferably 10 parts by mass or less.

  Examples of mold release agents include hydrocarbon waxes such as polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, Sazol wax, and oxides thereof; carnauba wax, montan Waxes and ester-based waxes such as deacidified waxes and fatty acid ester waxes; fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts and the like can be mentioned, and these can be used alone or in combination of two or more.

  The melting point of the releasing agent is preferably 60 ° C. or more, more preferably 70 ° C. or more from the viewpoint of transferability of the toner, and preferably 160 ° C. or less, more preferably 140 ° C. from the viewpoint of low temperature fixability. The temperature is further preferably 120 ° C. or less, more preferably 110 ° C. or less.

  The content of the releasing agent is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the binder resin from the viewpoints of low-temperature fixability and offset resistance of the toner and the dispersibility in the binder resin. The amount is preferably 1.0 part by mass or more, more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass or less, still more preferably 7 parts by mass or less.

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

  As positively chargeable charge control agents, 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” (all, manufactured by Orient Chemical Industries Ltd.), etc .; Triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds, eg, "Bontron P-51" (manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethyl ammonium bromide, "COPY CHARGE PX VP 435" (manufactured by Clariant Co., Ltd.), etc .; Polyamine resin, such as "AFP-B" (Orient Chemical Industry Co., Ltd.) Imidazole derivatives, such as “PLZ-2001”, “PLZ-8001” (above, made by Shikoku Kasei Kogyo Co., Ltd.), etc .; styrene-acrylic resins, such as “FCA-701PT” (Fujikura Kasei Co., Ltd.) ), And the like.

  In addition, as a negatively chargeable charge control agent, metal-containing azo dyes such as "VALIFAST BLACK 3804", "BONTRON S-31", "BONTRON S-32", "BONTRON S-34", "BONTRON S-36" (Above, made by Orient Chemical Industry Co., Ltd.), “Eisen spirone black TRH”, “T-77” (made by Hodogaya Chemical Industry Co., Ltd.), etc .; metal compounds of benzyl acid compounds, for example, “LR- 147 "," LR-297 "(above, manufactured by Nippon Carlit Co., Ltd., etc.); metal compounds of salicylic acid compounds, for example," Bontron E-81 "," Bontron E-84 "," Bontron E-88 "," Bontron E-304 "(above, made by Orient Chemical Industry Co., Ltd.)," TN-105 "(made by Hodogaya Chemical Co., Ltd.), etc .; copper phthalocyanine dye; quaternary ammonium salt, eg," COPY CHARGE NX VP434 " (Manufactured by Clariant), nitroimidazole derivatives, etc .; organic gold And compounds of the genus.

  The content of the charge control agent is preferably 0.01 parts by mass or more, more preferably 0.2 parts by mass or more, and preferably 10 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of charge stability of the toner. It is preferably at most 5 parts by mass, more preferably at most 3 parts by mass, further preferably at most 2 parts by mass.

  The toner of the present invention may be a toner obtained by any of conventionally known methods such as a melt-kneading method, an emulsion phase inversion method, a polymerization method, etc., but from the viewpoint of productivity and dispersibility of colorants, A pulverized toner by a melt-kneading method is preferred. In the case of a pulverized toner by the melt-kneading method, for example, after uniformly mixing raw materials such as a binder resin, a colorant, a release agent, a charge control agent and the like with a mixer such as a Henschel mixer, a closed kneader, uniaxial or 2 It can be produced by melt-kneading with a shaft extruder, an open roll kneader, etc., followed by cooling, crushing and classification.

  In the toner of the present invention, an external additive is preferably used in order to improve the transferability. Examples of the external additive include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide and zinc oxide, and organic fine particles such as resin particles such as melamine resin fine particles and polytetrafluoroethylene resin fine particles, and the like. The above may be used in combination. Among these, silica is preferable, and from the viewpoint of the transferability of the toner, hydrophobic silica treated with hydrophobic treatment is more preferable.

  Examples of hydrophobizing agents for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), methyltriethoxysilane, etc. Be

  The average particle size of the external additive is preferably 10 nm or more, more preferably 15 nm or more, and preferably 250 nm or less, more preferably 200 nm or less, from the viewpoint of chargeability, flowability and transferability of the toner. Preferably it is 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 with respect to 100 parts by mass of the toner before being treated with the external additive, from the viewpoints of chargeability, fluidity, and transferability of the toner. The amount is preferably at least 0.3 parts by mass, and more preferably at most 5 parts by mass, more preferably at most 3 parts by mass.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably 3 μm or more, more preferably 4 μm or more, and preferably 15 μm or less, more preferably 10 μm or less. In the present specification, the volume median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by volume fraction is 50% as 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 taken as the volume median particle size of the toner.

  The toner of the present invention can be used as an one-component developing toner as it is or as a two-component developing toner to be used by mixing with a carrier, in an image forming apparatus of a one-component developing system or a two-component developing system.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by these examples. Physical properties of the resin and the like were measured by the following methods.

[IV value of PET]
The sample can be dissolved in a mixed solvent of phenol / tetrachloroethane (mass ratio) 60/40 at a concentration of 4 g / L, measured with a Ubbelohde viscometer, and calculated according to the following formula .
IV = (-1 + ((1 + 4 k))) / (2 kC)
[Wherein, k = 0.33, C = 0.004 g / mL, and η = (t1 / t0) -1 (t0: number of seconds dropped by solvent only, t1: number of seconds dropped by sample solution)]. ]

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

[Maximum peak temperature of endotherm of resin]
0.01 to 0.02 g of a sample is weighed in an aluminum pan using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), and a temperature decrease rate of 10 ° C. from room temperature (25 ° C.) Cool to 0 ° C./min and maintain at 0 ° C. for 1 minute. Thereafter, measurement is performed at a temperature rising rate of 10 ° C./min. Of the observed endothermic peaks, the temperature of the peak located on the highest temperature side is taken as the highest endothermic peak temperature.

[Glass transition temperature of resin]
Using a differential scanning calorimeter “DSC Q20” (manufactured by TA Instruments Japan), measure 0.01 to 0.02 g of a sample on an aluminum pan, raise the temperature to 200 ° C. Cool down to 0 ° C./min. Next, the sample is heated at a temperature rising rate of 10 ° C./min to measure an endothermic peak. The temperature at the intersection of the extension of the baseline below the highest endothermic peak temperature and the tangent showing the maximum slope from the rising portion of the peak to the peak of the peak is taken as the glass transition temperature.

[Acid value and hydroxyl value of resin]
It measures based on the method of JISK0070. However, only the measurement solvent is changed to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)) from a mixed solvent of ethanol and ether defined in JIS K0070.

Melting point of mold release agent
Using a differential scanning calorimeter “DSC Q20” (manufactured by TA Instruments Japan Co., Ltd.), measure 0.01 to 0.02 g of a sample on an aluminum pan, and heat up to 200 ° C. at a heating rate of 10 ° C./min. The temperature is raised and cooled to -10 ° C. at a temperature decrease rate of 5 ° C./min. Next, the sample is heated to 180 ° C. at a heating rate of 10 ° C./min and measured. The highest endothermic peak temperature observed from the melting endothermic curve obtained there is taken as the melting point of the release agent.

[Average particle size of external additive]
The average particle size refers to a number average particle size, and the particle size (average value of the major axis and the minor axis) of 500 particles is measured from a scanning electron microscope (SEM) photograph, and the number average value is taken.

[Toner volume median particle size]
Measuring machine: Coulter Multisizer II (manufactured by Beckman Coulter Co., Ltd.)
Aperture diameter: 100 μm
Analysis software: Coulter multisizer Accucomp version 1.19 (manufactured by Beckman Coulter Co., Ltd.)
Electrolyte: Isoton II (manufactured by Beckman Coulter Co., Ltd.)
Dispersion solution: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB (glyphin): 13.6) dissolved in electrolyte to adjust to 5% by mass Dispersion conditions: 10 mg of measurement sample in 5 mL of the dispersion Is added, and dispersed for 1 minute with an ultrasonic disperser (machine name: US-1, manufactured by SND Co., Ltd., output: 80 W), and then 25 mL of the electrolyte is added, and further, to the ultrasonic disperser Disperse for 1 minute to prepare a sample dispersion.
Measurement conditions: The sample dispersion is added to 100 mL of the electrolyte so that the particle size of 30,000 particles can be measured in 20 seconds, 30,000 particles are measured, and the volume is determined from the particle size distribution. Determine the median particle size (D ₅₀ ).

Resin Production Example 1 (Resins 1 to 17)
The raw material monomers of polyester resins other than trimellitic anhydride shown in Tables 1 to 3 are put into a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a downflow condenser and a nitrogen inlet tube, The temperature was raised to 160 ° C. in a mantle heater in an atmosphere. A mixture of a raw material monomer of a styrenic resin shown in Tables 1 to 3, a bireactive monomer, and a polymerization initiator shown in Tables 1 to 3 was dropped to perform polymerization. Thereafter, an esterification catalyst was added, and the temperature was raised to 210 ° C. over 5 hours. Thereafter, trimellitic anhydride was added, the temperature was raised to 220 ° C., and the reaction was carried out until the softening point shown in Tables 1 to 3 was reached at 8.0 kPa to obtain an amorphous composite resin.

Resin Production Example 2 (Resin 18)
Raw material monomers and reactive monomers of polyester resins other than trimellitic anhydride shown in Table 3 in a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a downflow condenser, and a nitrogen inlet tube Then, the temperature was raised to 160 ° C. in a mantle heater in a nitrogen atmosphere. The mixture of the raw material monomer of a styrene resin and a polymerization initiator was dripped there, and it superposed | polymerized. Thereafter, an esterification catalyst was added, and the temperature was raised to 210 ° C. over 5 hours. Thereafter, trimellitic anhydride was added, the temperature was raised to 220 ° C., and the reaction was carried out until the softening point shown in Table 3 was reached at 8.0 kPa to obtain an amorphous composite resin.

Resin Production Example 3 (Resin 19)
Raw material monomers and esterification catalyst of polyester resin other than trimellitic anhydride shown in Table 3 are put into a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a downflow condenser and a nitrogen introducing pipe. The temperature was raised to 210 ° C. over 5 hours in a mantle heater in a nitrogen atmosphere. Thereafter, trimellitic anhydride was added, the temperature was raised to 220 ° C., and the reaction was carried out until the softening point shown in Table 3 was reached at 8.0 kPa to obtain an amorphous composite resin.

Resin Production Example 4 (Resins C1, C2)
The alcohol component and the carboxylic acid component shown in Table 4 are placed in a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a downflow condenser and a nitrogen inlet tube, and in a mantle heater in a nitrogen atmosphere The temperature was raised to 200 ° C. over 8 hours. Thereafter, an esterification catalyst was added, and the reaction was carried out until the softening point shown in Table 4 was reached at 8.0 kPa to obtain a crystalline polyester resin.

Examples 1 to 16 and Comparative Examples 1 to 5
100 parts by mass of binder resin shown in Table 5, 5 parts by mass of coloring agent "ECB-301" (manufactured by Dainichi Seika Kogyo Co., Ltd.), 1 mass of charge control agent "LR-147" (manufactured by Nippon Carlit Co., Ltd.) Part and mold release agent "Carnauba wax C 1" (product of Kato Yoko Co., melting point: 80 ° C) after thoroughly stirring with a Henschel mixer, the total length of the kneading part 1560 mm, screw diameter 42 mm, barrel inner diameter The mixture was melt-kneaded using a 43 mm co-rotating twin-screw extruder. The rotation speed of the roll was 200 r / min, the heating set temperature in the roll was 90 ° C., the temperature of the kneaded product was 140 ° C., the feed rate of the kneaded product was 10 kg / h, and the average residence time was about 18 seconds. The resulting kneaded product is cooled from 140 ° C. to 50 ° C. for 1.5 hours, rolled and cooled at 50 ° C. with a cooling roller, allowed to stand at 45 ° C. for 4 hours, pulverized by a jet mill, and classified. Toner particles having a particle diameter (D ₅₀ ) of 5.5 μm were obtained.

  “Aerosil R-972” (hydrophobic silica, manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle diameter: 16 nm) 1.5 parts by mass as an external additive with respect to 100 parts by mass of the obtained toner particles And “RY-50” (hydrophobic silica, manufactured by Nippon Aerosil Co., Ltd., hydrophobization treatment agent: silicone oil, average particle diameter: 40 nm) 1.0 part by mass is added, and mixed for 5 minutes at 3600 r / min with a Henschel mixer Thus, the external additive treatment was performed to obtain a toner.

Test Example 1 [Low-Temperature Fixing Property]
The toner was mounted on an apparatus improved from the fixing apparatus of the copying machine "AR-505" (manufactured by Sharp Corporation) so as to be able to fix the apparatus outside the apparatus, and an unfixed image was obtained.
After that, the fixing test of the unfixed image is performed at each temperature while sequentially raising the temperature from 100 ° C. to 240 ° C. by 5 ° C. in a fixing device (fixing speed 480 mm / sec) adjusted so that the total fixing pressure is 40 kgf. The A “UNICEF Cellophane” (Mitsubishi Pencil Co., Ltd., width: 18 mm, JIS Z-1522) was attached to the fixed image, and after passing through a fixing roller set at 30 ° C., the tape was peeled off. The optical reflection density before and after sticking the tape is measured using a reflection densitometer “RD-915” (manufactured by Macbeth), and the ratio of both (after peeling / before sticking) is first fixed at over 90%. The temperature of the roller was taken as the minimum fixing temperature. The results are shown in Table 5. The paper used for the fixing test is Copy Bond SF-70NA (75 g / m ² ) manufactured by Sharp Corporation.

Test Example 2 (Durability)
A toner is mounted on a printing machine “Page Press N-N” (made by Casio Computer Co., Ltd., fixing: contact fixing method, development: non-magnetic one-component development method, developing roll diameter: 2.3 cm), temperature 32 ° C., relative A pattern of diagonal stripes having a blackening rate of 5.5% was continuously printed under an environment of 85% humidity. On the way, a black solid image was printed every 500 sheets, and the presence or absence of streaks on the image was confirmed. Printing was stopped when streaks occurred on the image, and printing was performed up to 9000 sheets. The number of printed sheets up to the point when streaks were visually observed on the image was regarded as the number of sheets where streaks occurred due to the toner being fused and fixed to the developing roll, and the durability was evaluated. That is, it can be judged that the durability of the toner is higher as the number of sheets in which streaks do not occur is larger. The results are shown in Table 5.

Test Example 3 [Charge stability under high temperature and high humidity]
0.6 g of toner and 19.4 g of silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle diameter 90 μm) under high temperature and high humidity conditions of a temperature of 32 ° C. and a relative humidity of 85% are put in a 50 mL poly bottle The charge amount of the toner was measured using a Q / M meter (manufactured by EPPING) according to the following method.
After the specified mixing time, charge the specified amount of toner and carrier mixture into the cell attached to the Q / M meter, and suction only the toner for 90 seconds through a 32 μm mesh sieve (stainless, twill, wire diameter: 0.0035 mm) did. The voltage change on the carrier generated at that time was monitored, and the value of [total electric quantity (μC) after 90 seconds / suctioned toner quantity (g)] was taken as the charge quantity (μC / g). The charge stability was evaluated by calculating the ratio of the charge amount after 60 seconds of mixing time and the charge amount after 600 seconds of mixing time (charge amount after 60 seconds of mixing time / charge amount after 600 seconds of mixing time). The larger the value, the better the charging stability under high temperature and high humidity. The results are shown in Table 5.

From the above results, it can be seen that the toners of Examples 1 to 16 are all good in low-temperature fixability, durability, and charge stability under high temperature and high humidity.
On the other hand, Comparative Example 1 in which the amount of use of aliphatic diol having two hydroxyl groups bonded to primary carbon atoms is too small and Comparative Example 2 in which ethylene glycol is used without using PET is durability and charging It turns out that the stability is insufficient. Further, Comparative Examples 3 and 4 in which acrylic acid or fumaric acid was used as a bireactive monomer, were all insufficient in low-temperature fixability, durability and charge stability, and contained polyester resin instead of composite resin. It is understood that the toner of Comparative Example 5 has insufficient durability and charging stability.

  The binder resin composition for toner according to the present invention is, for example, a binder resin of an electrophotographic toner used for developing a latent image formed in an electrostatic charge image developing method, electrostatic recording method, electrostatic printing method or the like. Are preferably used.

Claims (8)

  Polyester resin which is a polycondensation reaction product of an alcohol component containing 40 mol% to 100 mol% of an aliphatic diol having two hydroxyl groups bonded to primary carbon atoms and a carboxylic acid component and polyethylene terephthalate, styrene A composite resin in which a styrenic resin, which is an addition polymer of a raw material monomer containing a compound, is chemically bonded via one or two or more types of dual reactive monomers selected from acrylic acid ester and methacrylic acid ester Binder resin composition for toners contained.   The binder resin composition for toner according to claim 1, wherein a mass ratio of the bireactive monomer to the raw material monomer of the styrene resin (bireactive monomer / raw material monomer of the styrene resin) is 5/95 or more and 50/50 or less. object.   The binder resin composition for toner according to claim 1 or 2, wherein a mass ratio of the polyester resin to the styrene resin (polyester resin / styrene resin) is 60/40 or more and 95/5 or less.   The toner binder resin composition according to any one of claims 1 to 3, wherein the IV value of polyethylene terephthalate is 0.40 or more and 0.80 or less.   The binder resin composition for toner according to any one of claims 1 to 4, wherein the acrylic acid ester or methacrylic acid ester is an acrylic acid alkyl ester or a methacrylic acid alkyl ester having 2 to 6 carbon atoms in the alkyl group. .   The binder resin composition for toner according to any one of claims 1 to 5, wherein the aliphatic diol having two hydroxyl groups bonded to a primary carbon atom contains at least neopentyl glycol.   A hydroxyl group bonded to a primary carbon atom after the step of addition polymerizing a raw material monomer containing a styrene compound in the presence of one or more kinds of both reactive monomers selected from acrylic acid ester and methacrylic acid ester A method for producing a binder resin composition for toner, comprising the step of polycondensing an alcohol component containing 40 mol% to 100 mol% of an aliphatic diol having two, a carboxylic acid component and a polyethylene terephthalate.   An electrophotographic toner comprising the binder resin composition for toner according to any one of claims 1 to 6.