JP6762788B2 - Bound resin composition for toner - Google Patents

Description

The present invention provides, for example, a binder resin composition for toner used for developing a latent image formed by an electrophotographic method, an electrostatic recording method, an electrostatic printing method, etc., a method for producing the same, and the binder resin composition. Regarding the contained electrophotographic toner.

In recent years, as the speed and energy saving of printers and copiers have increased, toner having excellent low-temperature fixability has become increasingly necessary. As a means for improving fixability and durability, a composite resin of a polyester resin obtained by reacting polyethylene terephthalate as a raw material by transesterification and a styrene acrylic resin is known (see Patent Documents 1 and 2).

JP-A-2009-276791 Japanese Unexamined Patent Publication No. 8-239409

However, the composite resins described in Patent Documents 1 and 2 are not satisfactory in terms of low-temperature fixability, image density, toner charge riseability, and charge stability.

The present invention relates to a binder resin composition for toner, which is excellent in low temperature fixability, image density, charge rising property, and charge stability, a method for producing the same, and an electrophotographic toner containing the binder resin composition.

The present invention
[1] A polyester resin obtained by polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component and polyethylene terephthalate, and a vinyl resin obtained by addition polymerization of an addition-polymerizable monomer are said to have polycondensability. The polyethylene terephthalate contains a polyethylene terephthalate having an IV value of 0.40 or more and 0.75 or less, which contains an amorphous composite resin chemically bonded via a bireactive monomer capable of reacting with any of the monomer and the addition polymerizable monomer. , Bundling resin composition for toner,
[2] A step A of addition polymerization of an addition polymerizable monomer and a bireactive monomer, and a step B of polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component with polyethylene terephthalate are included. A method for producing a binder resin composition for toner, wherein step B is carried out in the same reaction vessel, wherein the polyethylene terephthalate contains polyethylene terephthalate having an IV value of 0.40 or more and 0.75 or less. The present invention relates to a manufacturing method and [3] an electrophotographic toner containing the binder resin composition for a toner according to the above [1].

The electrophotographic toner containing the binder resin composition for a toner of the present invention exerts excellent effects in low temperature fixability, image density, charge rising property, and charge stability.

The binder resin composition for toner of the present invention is obtained by addition polymerization of a polyester resin obtained by polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component and polyethylene terephthalate, and an addition-polymerizable monomer. The vinyl resin contains an amorphous composite resin that is chemically bonded via both reactive monomers that can react with both the polycondensable monomer and the addition-polymerizable monomer, and the polyethylene terephthalate has an IV value of 0.40 or more and 0.75. It contains the following polyethylene terephthalates.

The reason why the binder resin composition for toner of the present invention is excellent in low temperature fixability, image density, charge rising property, and charge stability is not necessarily clear, but it is considered as follows.

Polyethylene terephthalate (PET) introduced into a polyester resin usually used as a binder resin for toner has an IV value of about 0.80 to 1.10, and a PET having an IV value of 0.40 or more and 0.75 or less is a conventionally used PET. It has a low IV value, that is, a low molecular weight PET. Therefore, the depolymerization of PET proceeds more uniformly. As a result, since the PET skeleton having high polarity can be uniformly dispersed in the polymer, it is presumed that the dispersibility of the colorant is improved and the image density is increased as compared with the conventional PET-introduced resin. Further, it is presumed that the PET skeleton, which is a flexible skeleton, can be uniformly dispersed in the resin, so that the low temperature fixability is also improved. Further, since the vinyl moiety has a high aromatic ring concentration, it has the effect of increasing the charge stability, but the low vinyl moiety due to its low polarity has low compatibility with the highly polar PET skeleton, which worsens the dispersion of the vinyl moiety. It causes the toner surface to be exposed. In general, the vinyl portion has a lower charge rise than the polyester portion, which causes deterioration of the charge rise of the toner. Therefore, the conventional composite resin cannot achieve both charge stability and charge rise. However, it is presumed that by dispersing the PET skeleton using low IV PET, the dispersibility of the vinyl moiety and the polyester moiety is improved, and as a result, the charge rising property and the charge stability of the toner are improved.

In the amorphous composite resin, the polyester resin is a resin obtained by polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component with polyethylene terephthalate.

In the polycondensable monomer, as the carboxylic acid component, at least one selected from the group consisting of aromatic dicarboxylic acid compounds, aliphatic dicarboxylic acid compounds, and trivalent or higher valent carboxylic acid compounds is preferable, and charging rises. From the viewpoint of sex, it is more preferable to contain an aromatic dicarboxylic acid compound. In the present invention, the carboxylic acid compound includes not only free acids, but also anhydrouss that decompose during the reaction to generate acids, and alkyl esters having 1 or more and 3 or less carbon atoms.

Examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, and terephthalic acid; anhydrides of those acids, alkyl (1 to 3 carbon atoms) esters of those acids, and the like. Among these, terephthalic acid or isophthalic acid is preferable, and terephthalic acid is more preferable, from the viewpoint of low-temperature fixability.

The content of the aromatic dicarboxylic acid compound is preferably 20 mol% or more, more preferably 40 mol% or more, and preferably 95 mol% or less, more preferably, from the viewpoint of low-temperature fixability in the carboxylic acid component. It is preferably 90 mol% or less, more preferably 80 mol% or less, still more preferably 70 mol% or less.

Aliphatic dicarboxylic acid compounds include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, alkyl groups having 1 to 20 carbon atoms or alkenyl groups having 2 to 20 carbon atoms. Aliphatic dicarboxylic acids such as succinic acid and adipic acid which may be substituted; anhydrides of those acids or alkyl (carbons 1 to 3) esters of those acids can be mentioned, and the number of carbon atoms is 1 or more and 20 or less. It is preferable to contain succinic acid substituted with an alkyl group or an alkenyl group having 2 or more and 20 or less carbon atoms. The succinic acid is preferably succinic acid substituted with an alkyl group or alkenyl group having 6 to 14 carbon atoms, and more preferably succinic acid substituted with an alkyl group or alkenyl group having 8 to 12 carbon atoms. Is. Specific examples thereof include octyl succinic acid and dodecenyl succinic acid (tetrapropenyl succinic acid).

The content of the aliphatic dicarboxylic acid compound is preferably 2 mol% or more, more preferably 5 mol% or more, and preferably from the viewpoint of storage stability, in the carboxylic acid component from the viewpoint of low temperature fixability. It is 50 mol% or less, more preferably 40 mol% or less, still more preferably 30 mol% or less.

Examples of trivalent or higher carboxylic acid compounds include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, acid anhydrides thereof, and lower alkyl (lower alkyl). Examples thereof include esters having 1 to 3 carbon atoms, and among these, trimellitic acid-based compounds, for example, trimellitic acid or an acid anhydride thereof are preferable.

The content of the trivalent or higher carboxylic acid compound is preferably 10 mol% or more, more preferably 15 mol% or more from the viewpoint of low-temperature fixability in the carboxylic acid component, and from the viewpoint of storage stability. It is preferably 50 mol% or less, more preferably 40 mol% or less, still more preferably 35 mol% or less.

As the alcohol component, from the viewpoint of low temperature fixability, formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is ethylene and / or propylene group, x and y indicate the average number of moles of alkylene oxide added, which are positive numbers, respectively, of x and y. The value of the sum is 1 or more, preferably 1.5 or more, 16 or less, preferably 8 or less, and more preferably 4 or less).
It is preferable to contain an alkylene oxide adduct of bisphenol A represented by. Examples of the alkylene oxide adduct of bisphenol A represented by the formula (I) include a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane and 2,2-bis (4-hydroxyphenyl) propane. Examples thereof include polyoxyethylene adducts. It is preferable to use one or more of these.

The content of the alkylene oxide adduct of bisphenol A represented by the formula (I) is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, still more preferably 95 mol% or more in the alcohol component. It is 100 mol%.

Other alcohol components include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,4-butane. Examples thereof include aliphatic diols such as diol, 1,3-butanediol and neopentyl glycol, and trihydric or higher alcohols such as glycerin.

A monohydric alcohol may be appropriately contained in the alcohol component, and a monovalent carboxylic acid compound may be appropriately contained in the carboxylic acid component.

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

As the polyethylene terephthalate (PET), those produced according to a conventional method by polycondensation of ethylene glycol with terephthalic acid, dimethyl terephthalate and the like can be used. In the present invention, PET is partially converted into oligomers, ethylene glycol or terephthalic acid by depolymerization reaction under polycondensation reaction conditions, and the depolymerization component thereof or the alcohol component which is a polycondensation monomer with PET. It is finally incorporated into the polyester resin by the polycondensation reaction with the carboxylic acid component.

In the present invention, the PET subjected to polycondensation contains polyethylene terephthalate having a low IV value.

The IV value of PET with a low IV value is 0.40 or more, preferably 0.50 or more, more preferably 0.55 or more from the viewpoint of image density, and 0.75 or less, preferably 0.68 or less from the viewpoint of homogenization of depolymerization. , More preferably 0.65 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 and the like. Further, PET having a high IV value may be decomposed by depolymerization to adjust to a low IV value.

Commercially available low IV PET products preferably used in the present invention include RAMAPET L1 (Indorama Ventures, IV value: 0.6), RAMAPET N2G (Indorama Ventures, IV value: 0.75), TRN-NTJ ( Teijin Limited, IV value: 0.53), TRN-RTJC (Teijin Co., Ltd., IV value: 0.64) and the like.

The content of PET having a low IV value is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, still more preferably 100% by mass, based on the total amount of PET subjected to polycondensation. Is. PETs having an IV value outside the above range may be contained within a range that does not impair the effects of the present invention, but the content of these PETs is preferably 10% by mass or less, more preferably 5% by mass or less. , More preferably 2% by mass or less, still more preferably 0% by mass.

In the PET to be subjected to polycondensation, the terephthalate-ethylene glycol unit (Mw: 192) is preferably 5 mol or more, more preferably 5 mol or more, based on a total of 100 mol of the alcohol component and PET. It is preferably used in an amount of 10 mol or more, more preferably 20 mol or more, and from the viewpoint of charge stability, preferably 80 mol or less, more preferably 70 mol or less, still more preferably 60 mol or less. ..

The polycondensation reaction between a polycondensable monomer containing a carboxylic acid component and an alcohol component and PET (including the depolymerization component of PET as described above) is carried out, for example, in an inert gas atmosphere, preferably an esterification catalyst. It can be carried out at a temperature of 180 ° C. or higher and 250 ° C. or lower in the presence of an esterification co-catalyst, a polymerization inhibitor and the like, if necessary. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin (II) 2-ethylhexanoate, and titanium compounds such as titanium diisopropyrate bistriethanolamate. Examples of the esterification co-catalyst that can be used together with the esterification catalyst include gallic acid and the like. The amount of the esterification catalyst used is preferably 0.01 part by mass or more, more preferably 0.1 part by mass or more, and preferably 1 part by mass with respect to 100 parts by mass of the total amount of PET, alcohol component, and carboxylic acid component. Hereinafter, it is more preferably 0.6 parts by mass or less. The amount of the esterification cocatalyst used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and preferably 0.5 part by mass with respect to 100 parts by mass of the total amount of PET, alcohol component, and carboxylic acid component. Parts or less, more preferably 0.1 parts by mass or less.

The vinyl resin is a resin obtained by addition polymerization of an addition-polymerizable monomer.

The addition-polymerizable monomer preferably contains styrene or a styrene derivative such as α-methylstyrene or vinyltoluene (hereinafter, styrene and the styrene derivative are collectively referred to as “styrene compound”).

The content of the styrene compound in the addition-polymerizable monomer is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 90% by mass or more from the viewpoint of charge stability.

Other addition-polymerizable monomers include ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; (meth). ) Ethylene monocarboxylic acid esters such as dimethylaminoethyl acrylate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone and the like. The addition-polymerizable monomer does not contain a polymerization initiator.

The addition polymerization reaction of the addition-polymerizable monomer can be carried out by a conventional method in the presence of a polymerization initiator such as dicumyl peroxide, a cross-linking agent or the like, in the presence of an organic solvent or in the absence of a solvent. The temperature conditions are preferably 110 ° C. or higher, more preferably 140 ° C. or higher, and preferably 200 ° C. or lower, more preferably 170 ° C. or lower.

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

The bireactive monomer that binds the polyester resin and the vinyl resin is a monomer that can react with both the polycondensable monomer and the addition-polymerizable monomer. In the present invention, the bireactive monomer has low temperature fixability and charge rising property. , And, from the viewpoint of image density, it is preferable to contain a (meth) acrylic acid alkyl ester having 2 or more and 6 or less carbon atoms in the alkyl group. In addition, in this specification, "(meth) acrylic acid" means acrylic acid, methacrylic acid, or both.

Specific examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, (iso) propyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and ( Examples thereof include butyl (iso or tertiary) acrylate (meth) acrylate, (iso) hexyl (meth) acrylate, and butyl (meth) acrylate is preferable. The alkyl group may have a substituent such as a hydroxyl group, and "(iso or tertiary)" and "(iso)" include both the case where these groups are present and the case where they are not present. This means that if these groups do not exist, it indicates that they are normal.

The alkyl group of the (meth) acrylic acid alkyl ester has 2 or more carbon atoms, preferably 3 or more carbon atoms, more preferably 4 carbon atoms, and 6 or less, preferably 4 or less carbon atoms.

The content of the (meth) acrylic acid alkyl ester having 2 or more and 6 or less carbon atoms in the alkyl group is preferably 85 mol% or more, more preferably 90 mol% or more, and further preferably 95 mol% in both reactive monomers. Above, it is more preferably 100 mol%.

Examples of the other bireactive monomer include at least one functional group, preferably a hydroxyl group, selected from the group consisting of a hydroxyl group, a carboxy group, an epoxy group, a primary amino group and a secondary amino group in the molecule. / Or a compound having a carboxy group, more preferably a carboxy group and an ethylenically unsaturated bond, such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride and the like. However, when used together with a polymerization inhibitor, a polyvalent carboxylic acid compound having an ethylenically unsaturated bond such as fumaric acid functions as a polycondensable monomer. In this case, fumaric acid and the like are not bireactive monomers but polycondensable monomers.

The amount of the bireactive monomer having a carboxy group and an ethylenically unsaturated bond is preferably not used or is small, and even if it is used, the content thereof is the content of all the bireactive monomers. Medium, preferably 5% by mass or less, more preferably 3% by mass or less.

The content of the bireactive monomer in the total amount of the addition polymerizable monomer and the bireactive monomer is preferably 30% by mass or more, more preferably 40% by mass or more, and from the viewpoint of gloss and storage stability. It is preferably 80% by mass or less, more preferably 70% by mass or less, and further preferably 60% by mass or less.

The amorphous composite resin contained in the binder resin composition in the present invention is subjected to a step A of addition polymerization of an addition polymerizable monomer and a bireactive monomer and a step B of polycondensing a polycondensable monomer and PET. Including, those obtained by a method in which the step A and the step B are carried out in the same reaction vessel are preferable.

Step A and step B may be carried out sequentially or simultaneously, but in the present invention, it is preferable to carry out step B after performing step A. As a result, in the method in which the polycondensation reaction is carried out before the addition polymerization reaction, the amount of the alcohol component used in the transesterification reaction is reduced, whereas the bireactive monomer and the terminal hydroxyl group of the alcohol component are efficiently transesterified. It is considered that a crosslinked structure is formed.

The polycondensation reaction may be carried out in the presence of an addition-polymerizable monomer and / or a bireactive monomer, and the addition polymerization reaction may be carried out in the presence of a polycondensation monomer and / or PET. In the method in which step B is performed later, from the viewpoint of making the molecular weight distribution of the produced vinyl resin uniform, it is preferably in the presence of PET, more preferably in the presence of PET and a polycondensable monomer other than the trivalent or higher valent monomer. , It is desirable to carry out step A. A trivalent or higher monomer such as a trivalent or higher carboxylic acid compound or a trivalent or higher alcohol increases the viscosity of the polyester and the molecular weight distribution of the produced vinyl resin becomes non-uniform, so that the reaction occurs after the step A. It is preferable to add it to the system.

The mass ratio of the total amount of the polyester resin, the vinyl resin, and the bireactive monomer in the amorphous composite resin (the total amount of the polyester resin / vinyl resin and the bireactive monomer) is the low temperature fixability, the charge rise property, and the image. From the viewpoint of concentration, it is preferably 60/40 or more, more preferably 65/35 or more, and from the viewpoint of charge stability, it is preferably 95/5 or less, more preferably 90/10 or less, still more preferably 85. It is less than / 15. In the above calculation, the mass of the polyester resin is an amount obtained by subtracting the amount of reaction water (calculated value) dehydrated by the polycondensation reaction from the total amount of the polycondensable monomer and PET used. The mass of the vinyl resin is the mass of the addition-polymerizable monomer, and does not include the amount of the polymerization initiator.

The softening point of the amorphous composite resin is preferably 80 ° C. or higher, more preferably 85 ° C. or higher from the viewpoint of storage stability, and preferably 170 ° C. or lower, more preferably 170 ° C. or lower from the viewpoint of low temperature fixability. It is below 150 ° C.

The crystallinity of the resin is represented by the crystallinity index defined by the ratio of the softening point to the maximum endothermic temperature measured by the differential scanning calorimeter, that is, the value of [softening point / maximum endothermic temperature]. The amorphous resin is a resin having a crystallinity index of more than 1.4, preferably more than 1.5, more preferably 1.6 or more, or less than 0.6, preferably 0.5 or less. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers, the production conditions (for example, reaction temperature, reaction time, cooling rate) and the like. The maximum endothermic peak temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks.

The glass transition temperature of the amorphous composite resin is preferably 40 ° C. or higher, more preferably 50 ° C. or higher from the viewpoint of storage stability, and preferably 80 ° C. or lower, more preferably from the viewpoint of low temperature fixability. Is 70 ° C. or lower, more preferably 60 ° C. or lower.

The acid value of the amorphous composite resin is preferably 10 mgKOH / g or more, more preferably 15 mgKOH / g or more from the viewpoint of charge rising property, and preferably 40 mgKOH / g or less from the viewpoint of hygroscopicity. It is preferably 30 mgKOH / g or less.

When the binder resin composition of the present invention is composed of two or more kinds of resins, it is preferable that their weighted average values are within the above range.

From the viewpoint of low temperature fixability and hot offset resistance, the binder resin composition of the present invention preferably contains two types of resins having different softening points of 15 ° C. or more, and one of them uses the PET. A resin other than the amorphous composite resin may be used, but it is more preferable that at least one of them is an amorphous composite resin using the PET, and all of them are the amorphous composite resin using the PET. Is even more preferable.

The softening point of the resin H having the higher softening point is preferably 110 ° C. or higher, more preferably 130 ° C. or higher from the viewpoint of hot offset resistance, and preferably 170 ° C. or lower from the viewpoint of low temperature fixability. , More preferably 150 ° C. or lower.

The softening point of the resin L having the lower softening point is preferably 80 ° C. or higher, more preferably 90 ° C. or higher from the viewpoint of hot offset resistance, and preferably 120 ° C. or lower from the viewpoint of low temperature fixability. , More preferably 110 ° C. or lower.

The difference between the softening points of the resin H and the resin L is preferably 15 ° C. or higher, more preferably 20 ° C. or higher, and preferably 60 ° C. or lower, more preferably 60 ° C. or lower, from the viewpoint of low temperature fixability and hot offset resistance. It is below 50 ° C.

The softening point of the resin can be adjusted by the degree of cross-linking or the like. From this point of view, the resin H preferably contains a trimellitic acid-based compound, and the content of the trimellitic acid-based compound in the carboxylic acid component is preferably 5 mol% or more, more preferably 10 mol% or more. And, from the viewpoint of low temperature fixability, it is preferably 35 mol% or less. Further, the resin H preferably contains an aliphatic dicarboxylic acid compound from the viewpoint of low temperature fixability. The content of the aliphatic dicarboxylic acid compound is preferably 1 mol% or more, more preferably 2 mol% or more, and preferably from the viewpoint of charge rising property in the carboxylic acid component from the viewpoint of low temperature fixability. Is 40 mol% or less, more preferably 30 mol% or less.

On the other hand, the resin L preferably contains a trimellitic acid-based compound from the viewpoint of hot offset resistance, and the content of the trimellitic acid-based compound in the carboxylic acid component is preferably 20 mol% or less. is there.

The mass ratio of resin H to resin L (resin H / resin L) is preferably 20/80 or more, more preferably 40/60 or more, still more preferably 55/45 or more, and from the viewpoint of low temperature fixability. From the viewpoint of low temperature fixability and image density, it is preferably 90/10 or less, more preferably 80/20 or less, and further preferably 70/30 or less.

The electrophotographic toner of the present invention may contain a binder resin other than the resin composition of the present invention, for example, a polyester resin, a vinyl resin, an epoxy resin, a polycarbonate resin, a polyurethane resin, or the like. The content of the resin composition of the present invention is preferably 50% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass, from the viewpoint of improving the low-temperature fixability and durability of the toner in the binder resin. % Or more, more preferably 95% by mass or more, still more preferably 100% by mass.

The toner of the present invention includes colorants, mold release agents, charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, cleanability improvers and the like. Additives may be included.

As the colorant, dyes, pigments and the like used as colorants for toner 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, carmin 6B, isoindoline, disazoero, etc. .. 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, and more preferably 2 parts by mass or more, based on 100 parts by mass of the binder resin, from the viewpoint of improving the image concentration and low temperature fixability of the toner. It is preferably 40 parts by mass or less, more preferably 20 parts by mass or less, and further preferably 10 parts by mass or less.

As the release agent, hydrocarbon waxes such as polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystallin wax, paraffin wax, Fishertropch wax, and sazole wax and their oxides; carnauba wax, montane. Waxes and ester-based waxes such as deoxidized 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 release agent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher from the viewpoint of toner transferability, and preferably 160 ° C. or lower, more preferably 140 ° C. or higher from the viewpoint of low temperature fixability. Below, it is more preferably 120 ° C. or lower, still more preferably 110 ° C. or lower.

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. It is preferably 1 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 either a positive charge control agent or a negative charge control agent.

Positive charge control agents include niglosin dyes such as "niglosin base EX", "oil black BS", "oil black SO", "bontron N-01", "bontron N-04", and "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, for example. "Bontron P-51" (manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant), etc .; Polyamine resin, for example, "AFP-B" (manufactured by Orient Chemical Industry Co., Ltd.) (Manufactured), etc .; imidazole derivatives such as "PLZ-2001", "PLZ-8001" (all manufactured by Shikoku Kasei Kogyo Co., Ltd.), etc .; styrene-acrylic resin, for example "FCA-701PT" (Fujikura Kasei Co., Ltd.) Made) and the like.

As the negative charge control agent, metal-containing azo dyes such as "Varifast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", and "Bontron S-36" (Above, manufactured by Orient Chemical Industry Co., Ltd.), "Eisenspiron Black TRH", "T-77" (manufactured by Hodoya Chemical Industry Co., Ltd.), etc .; Metal compounds of benzylic acid compounds, for example, "LR- 147 ”,“ LR-297 ”(above, manufactured by Nippon Carlit Co., Ltd.); metal compounds of salicylic acid compounds, for example,“ Bontron E-81 ”,“ Bontron E-84 ”,“ Bontron E-88 ”,“ Bontron E-304 "(above, manufactured by Orient Chemical Industry Co., Ltd.)," TN-105 "(manufactured by Hodoya Chemical Industry Co., Ltd.), etc .; copper phthalocyanine dye; quaternary ammonium salt, for example," COPY CHARGE NX VP434 " (Manufactured by Clariant), nitroimidazole derivatives and the like; organic metal compounds and the like can be mentioned.

The content of the charge control agent is preferably 0.01 part by mass or more, more preferably 0.2 part 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. Parts or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, still more preferably 2 parts by mass or less.

The toner of the present invention may be a toner obtained by any conventionally known method such as a melt-kneading method, an emulsification phase inversion method, a polymerization method, etc., but from the viewpoint of productivity and dispersibility of the colorant, the toner may be obtained. Crushed toner by the melt-kneading method is preferable. In the case of crushed toner by the melt-kneading method, for example, raw materials such as a binder resin, a colorant, a mold release agent, and a charge control agent are uniformly mixed with a mixer such as a Henschel mixer, and then a closed kneader, 1 shaft or 2 It can be manufactured by melt-kneading with a shaft extruder, an open roll type kneader, etc., cooling, crushing, and classifying.

It is preferable to use an external additive for the toner of the present invention in order to improve 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-based resin fine particles and polytetrafluoroethylene resin fine particles. The above may be used together. Among these, silica is preferable, and from the viewpoint of toner transferability, hydrophobized silica is more preferable.

Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octylliethoxysilane (OTES), and methyltriethoxysilane. Be done.

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, and further, from the viewpoint of toner chargeability, fluidity, and transferability. It is preferably 90 nm or less.

From the viewpoint of the chargeability, fluidity, and transferability of the toner, the content of the external additive is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass, based on 100 parts by mass of the toner before being treated with the external additive. More than parts, more preferably 0.3 parts by mass or more, and preferably 5 parts by mass or less, more preferably 3 parts by mass or less.

The volume median particle diameter (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 in which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size. When the toner is treated with an external additive, the volume median particle diameter of the toner particles before the toner is treated with the external additive is defined as the volume median particle diameter of the toner.

The toner of the present invention can be used as it is as a toner for one-component development or as a toner for two-component development used by mixing with a carrier, respectively, in a one-component development method or a two-component development method image forming apparatus.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. The physical properties of the resin and the like were measured by the following methods.
[IV value of PET]
It can be obtained by dissolving in a mixed solvent having a phenol / tetrachloroethane (mass ratio) of 60/40 at a concentration of 4 g / L, measuring with an Ubbelohde viscometer, and calculating according to the following formula.

IV = (-1 + √ (1 + 4kη)) / (2kC)
[In the formula, k = 0.33, C = 0.004 g / mL, and η = (t1 / t0) -1 (t0: number of seconds of solvent only falling, t1: number of seconds of sample solution falling). ]
[Resin softening point]
Using the 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 was applied by a plunger, and the diameter was 1 mm and the length was 1 mm. Push out from the nozzle. 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 used as the softening point.
[Maximum peak temperature of endothermic reaction of resin]
Using the differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample in an aluminum pan, and cool down from room temperature (25 ° C) to 10 ° C. Cool to 0 ° C at / min and maintain at 0 ° C for 1 minute. Then, the temperature is measured at a heating rate of 10 ° C./min. Among the observed endothermic peaks, the temperature of the peak on the highest temperature side is defined as the maximum endothermic temperature.
[Resin glass transition temperature]
Using the differential scanning calorimeter "DSC Q20" (manufactured by TA Instruments Japan), weigh 0.01 to 0.02 g of the sample in an aluminum pan, raise the temperature to 200 ° C, and then lower the temperature from that temperature to 10 Cool to 0 ° C at ° C / min. Next, the sample is heated at a heating rate of 10 ° C./min, and the endothermic peak is measured. The temperature at the intersection of the extension of the baseline below the maximum peak temperature of endothermic reaction and the tangent line indicating the maximum inclination from the rising portion of the peak to the peak of the peak is defined as the glass transition temperature.
[Acid value of resin]
Measure based on 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)).
[Melting point of mold release agent]
Using the differential scanning calorimeter "DSC Q20" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample in an aluminum pan, and heat up to 200 ° C at a temperature rise rate of 10 ° C / min. The temperature is raised and cooled from that temperature to -10 ° C at a temperature lowering rate of 5 ° C / min. Next, the sample is heated to 180 ° C. at a heating rate of 10 ° C./min and measured. The maximum peak temperature of heat absorption observed from the melt 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 the number average particle size, and the particle size (average value of major axis and minor axis) of 500 particles is measured from a scanning electron microscope (SEM) photograph and used as the number average value thereof.
[Medium particle size of toner]
Measuring machine: Coulter Multi-Sizar II (manufactured by Beckman Coulter Co., Ltd.)
Aperture diameter: 100 μm
Analysis software: Coulter Multi-Sizar AccuComp version 1.19 (manufactured by Beckman Coulter Co., Ltd.)
Electrolyte: Isoton II (manufactured by Beckman Coulter Co., Ltd.)
Dispersion: Emulgen 109P (manufactured by Kao Co., Ltd., polyoxyethylene lauryl ether, HLB (griffin): 13.6) was dissolved in an electrolytic solution to adjust the content to 5% by mass. Was added and dispersed with an ultrasonic disperser (machine name: US-1, manufactured by SND Co., Ltd., output: 80 W) for 1 minute, then 25 mL of the electrolytic solution was added, and the mixture was further added to the ultrasonic disperser. Disperse for 1 minute to prepare a sample dispersion.
Measurement conditions: Add the sample dispersion to 100 mL of the electrolytic solution so that the particle size of 30,000 particles can be measured in 20 seconds, measure 30,000 particles, and measure the volume from the particle size distribution. Determine the medium particle size (D ₅₀ ).
Resin Production Example 1 [Resin H1 to H10, L1 to L4]
Polycondensable monomers and PET other than trimellitic anhydride shown in Tables 1 to 3 are placed in a 10-liter four-necked flask equipped with a thermometer, a stainless stir bar, a flow-down condenser and a nitrogen introduction tube, and nitrogen is placed. The temperature was raised to 165 ° C in the mantle heater in the atmosphere. A mixture of an addition-polymerizable monomer, a bireactive monomer, and a polymerization initiator was added dropwise thereto to carry out polymerization.

Then, an esterification catalyst was added, the temperature was raised to 235 ° C over 3 hours, and the temperature was maintained for 7 hours after reaching 235 ° C. Then, after cooling to 210 ° C., trimellitic anhydride was added, the mixture was kept at 210 ° C. for 1 hour, a reduced pressure reaction was carried out at 8.0 kPa, and then the reaction was carried out until the softening point shown in Tables 1 to 3 was reached. , Amorphous composite resin was obtained.
Resin Production Example 2 [Resin H11, L5]
Raw material monomers other than trimellitic anhydride shown in Table 4 are placed in a 10-liter four-necked flask equipped with a thermometer, a stainless stir bar, a flow-down condenser, and a nitrogen introduction tube, and an esterification catalyst is placed in a nitrogen atmosphere. Was added, the temperature was raised to 235 ° C over 3 hours in a mantle heater, and the temperature was maintained for 7 hours after reaching 235 ° C. Then, after cooling to 210 ° C., trimellitic anhydride was added, the mixture was kept at 210 ° C. for 1 hour, a reduced pressure reaction was carried out at 8.0 kPa, and then the reaction was carried out until the softening point shown in Table 4 was reached, and amorphous. Quality polyester resin was obtained.

The PET used in the resin production example is as follows.
PET1: RAMAPET L1 (manufactured by Indorama Ventures), IV value: 0.6
PET2: RAMAPET N2G (manufactured by Indorama Ventures), IV value: 0.75
PET3: RAMAPET S1 (manufactured by Indorama Ventures), IV value: 0.84

Examples 1 to 14 and Comparative Examples 1 and 2 (Examples 2 and 13 are reference examples)
100 parts by mass of the binder resin shown in Table 5, 1 part by mass of the negative charge control agent "Bontron E-81" (manufactured by Orient Chemical Industry Co., Ltd.), and the colorant "Pigment blue 15: 3" (Dainichisei). After thoroughly mixing 5 parts by mass of Kagyo Kogyo Co., Ltd. and 2 parts by mass of the release agent "HNP-9" (manufactured by Nippon Seiwa Co., Ltd., paraffin wax, melting point: 80 ° C) with a Henschel mixer, knead. Using a biaxially rotating twin-screw extruder with a total length of 1560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm, the parts were melt-kneaded at a roll rotation speed of 200 r / min and a heating temperature of 100 ° C in the roll. The supply rate of the mixture was 20 kg / h and the average residence time was about 18 seconds. The obtained melt-kneaded product was cooled and roughly pulverized, then pulverized by a jet mill and classified to obtain toner particles having a volume medium particle size (D ₅₀ ) of 8 μm.

To 100 parts by mass of the obtained toner particles, 1.0 part by mass of hydrophobic silica "AEROSIL NAX 50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: HMDS, average particle size: about 30 nm) was added. , Toner was obtained by mixing with a Henschel mixer.
Test Example 1 [Low temperature fixability]
Toner is mounted on the non-magnetic one-component developing device "OKI MICROLINE 5400" (manufactured by Oki Data Co., Ltd.), and the amount of toner adhered is adjusted to 0.45 ± 0.03 mg / cm ² to produce a solid image of 4.1 cm x 13.0 cm. Printed on "J Paper" (manufactured by Fuji Xerox Office Supply Co., Ltd.). A solid image was taken out before passing through the fixing machine to obtain an unfixed image. The obtained unfixed image was fixed at a fixing speed of 240 mm / sec by setting the temperature of the fixing roll to 100 ° C with an external fixing machine modified from the fixing machine of "Microline 3010" (manufactured by Oki Data Corporation). It was. After that, the fixing roll temperature was set to 105 ° C., and the same operation was performed. While raising this to 200 ° C. by 5 ° C., the unfixed image was fixed at each temperature to obtain a fixed image. After attaching a mending tape (manufactured by 3M Japan Ltd.) to the image fixed at each temperature, a heavy stone on a cylinder of 500 g was placed on the image to sufficiently attach the tape to the fixed image. Then, the mending tape was slowly peeled off from the fixed image, and the optical reflection density of the image after the tape peeling was measured using a reflection densitometer "RD-915" (manufactured by Macbeth). The optical reflection density is also measured for the image before the tape is applied in advance, and the ratio to that value ([reflection density after tape peeling / reflection density before tape application] x 100) first exceeds 90%. The temperature of the roll was set as the minimum fixing temperature, and the low temperature fixing property was evaluated. The results are shown in Table 5. The lower the minimum fixing temperature, the better the low temperature fixing property.
Test Example 2 [Image density]
Using a commercially available printer (manufactured by Oki Data Co., Ltd., trade name: ML5400) on high-quality paper (manufactured by Fuji Xerox Office Supply Co., Ltd., J paper A4 size), the amount of toner adhered to the paper is 0.42 to 0.48 mg / A solid image of cm ² was output and a printed matter was obtained.

The reflected image density of the fixed image part of the printed matter is measured using a colorimeter (trade name: SpectroEye, manufactured by GretagMacbeth, light irradiation conditions; standard light source D ₅₀ , observation field of view 2 °, density standard DINNB, absolute white standard). The dispersibility of the colorant was evaluated. The results are shown in Table 5. The larger the value of the reflected image density, the higher the image density and the better the dispersibility of the colorant.
Test Example 3 [Chargeability]
After the specified mixing time, put the specified amount of toner and carrier mixture into the cell attached to the Q / M meter, and suck only the toner for 90 seconds through a sieve with a mesh opening of 32 μm (stainless steel, twill weave, wire diameter: 0.0035 mm). did. The voltage change on the carrier generated at that time was monitored, and the value of [total electricity amount (μC) after 90 seconds / suctioned toner amount (g)] was defined as the charge amount (μC / g).

The charge rising property and charge stability were evaluated from the ratio of the charge amount of the toner after each mixing time shown below. The results are shown in Table 5.
[Electrification rise]
The ratio of the charge amount after 30 seconds of mixing time to the charge amount after 60 seconds of mixing time (charge amount after 30 seconds of mixing time / charge amount after 60 seconds of mixing time) was calculated. The closer the ratio of the amount of charge is to 1, the better the charge rise property, and the ratio is preferably 0.75 or more, more preferably 0.85 or more, and even more preferably 0.95 or more.
[Charging stability]
The ratio of the charge amount after the mixing time of 60 seconds to the charge amount after the mixing time of 3600 seconds (charge amount after the mixing time of 3600 seconds / charge amount after the mixing time of 60 seconds) was calculated. The closer the ratio of the amount of charge is to 1, the better the charge stability, and the ratio is preferably 0.80 or more, more preferably 0.90 or more, and even more preferably 0.95 or more.

From the above results, it can be seen that the toners of Examples 1 to 14 are all good in low temperature fixability, image density, charge rising property, and charge stability.

On the other hand, the toner of Comparative Example 1 containing a binder resin using PET having a high IV value lacks low-temperature fixability and image density, and instead of PET, a binder resin using ethylene glycol is used. The toner of Comparative Example 2 contained is lacking in charge stability and image density.

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

Claims (6)

A polyester resin obtained by polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component and polyethylene terephthalate, and a vinyl resin obtained by addition polymerization of an addition polymerizable monomer are the polycondensable monomer and the polycondensable monomer. 90% by mass or more of polyethylene terephthalate having an IV value of 0.40 or more and 0.68 or less, containing an amorphous composite resin chemically bonded via a bireactive monomer capable of reacting with any of the addition polymerizable monomers. A binder resin composition for toner , wherein the bireactive monomer contains a (meth) acrylic acid alkyl ester having an alkyl group having 2 or more and 6 or less carbon atoms . The alcohol component is the formula (I):

(In the formula, RO and OR are oxyalkylene groups, R is ethylene and / or propylene group, x and y indicate the average number of moles of alkylene oxide added, which are positive numbers, respectively, of x and y. The value of the sum is 1 or more and 16 or less)
In formula comprising an alkylene oxide adduct of bisphenol A are, claim 1 Symbol placement toner binder resin composition. It contains two kinds of resins having different softening points of 15 ° C. or more, and the two kinds of resins are resin H having a softening point of 110 ° C. or higher and 170 ° C. or lower and resin L having a softening point of 80 ° C. or higher and 120 ° C. or lower. The binder resin composition for toner according to claim 1 or 2 , wherein at least one is the amorphous composite resin according to claim 1 or 2 . A step A of addition polymerization of an addition polymerizable monomer and a bireactive monomer, and a step B of polycondensing a polycondensable monomer containing a carboxylic acid component and an alcohol component with polyethylene terephthalate are included, and the steps A and B are included. is carried out in the same reaction vessel, a method for producing a binder resin for toner composition, wherein the polyethylene terephthalate is IV values observed including polyethylene terephthalate 0.40 0.68 or less 90% by mass or more, the dually reactive monomer A method for producing a binder resin composition for a toner, which contains a (meth) acrylic acid alkyl ester having an alkyl group having 2 or more and 6 or less carbon atoms . The manufacturing method according to claim 4 , wherein the step B is performed after the step A is performed. An electrophotographic toner containing the binder resin composition for toner according to any one of claims 1 to 3 .