JP7651602B2 - Polyester resin for toner and toner - Google Patents

Description

The present invention relates to a polyester resin for toner and a toner.

In recent years, with the trend toward higher speeds and energy saving in printers and copiers, there has been an increasing need for toners with excellent low-temperature fixability. However, when the molecular weight of the binder resin in a toner is reduced in order to melt it at a low temperature, the glass transition point of the resin is lowered, and the heat-resistant storage stability is reduced.
In order to solve this problem, polyesters obtained using carboxylic acids having aromatic rings, such as terephthalic acid and isophthalic acid, or alcohols having a bisphenol A structure as raw material monomers have been widely used as binder resins for toners that have a high glass transition point even though they have a low molecular weight (Patent Document 1).
On the other hand, since aromatic rings have higher polarity than aliphatic structures, the moisture absorption of the binder resin increases, resulting in a problem of deterioration of the moist and heat resistant storage stability of the toner.

JP 2009-251248 A

The objective of the present invention is to provide a toner with excellent humidity and heat resistance storage stability and low-temperature fixability by using the polyester resin for toner.

As a result of extensive research, the inventors have arrived at the present invention. That is, the present invention is a polyester resin for toner that is characterized by having a 1,3-dioxolane structure.

By using the polyester resin for toner of the present invention, it is possible to provide a toner with excellent humidity and heat resistance storage stability and low-temperature fixability.

The polyester resin for toner of the present invention is a polyester resin characterized by having a 1,3-dioxolane structure. By having the polyester resin have a 1,3-dioxolane structure, it is possible to obtain a toner having excellent moist heat resistant storage properties and low temperature fixing properties. The reason for this is thought to be that by using a compound having a 1,3-dioxolane structure as a raw material monomer for the polyester resin, a resin having a low melt viscosity can be obtained even if the glass transition point is high, resulting in excellent heat resistant storage properties and low temperature fixing properties for the toner, and the hydrophobicity of the 1,3-dioxolane structure reduces the moisture absorption of the resin, resulting in excellent moist heat resistant storage properties.

In the present invention, the polyester resin for toner is preferably a resin obtained by polycondensing a carboxylic acid component containing a carboxylic acid compound having at least a 1,3-dioxolane structure and/or an alcohol component containing an alcohol having a 1,3-dioxolane structure as a raw material monomer, and the carboxylic acid component and the alcohol component are polycondensed. The 1,3-dioxolane structure is preferably a structure represented by general formula (1), and more preferably 2,2-dimethyl-1,3-dioxolane.

In general formula (1), R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group.
Examples of the alkyl group include linear or branched alkyl groups having 1 to 18 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, and a decyl group.

Carboxylic acid compounds and alcohols having a 1,3-dioxolane structure can be obtained, for example, by subjecting a compound having an α,β-diol structure to an acetalization reaction with at least one compound selected from the group consisting of aldehyde compounds, ketone compounds, and acetal compounds, followed by isolation and purification as necessary.

The compound having an α,β-diol structure must have a hydroxyl group and/or a carboxyl group after acetalization, and therefore must be a compound having a hydroxyl group and/or a carboxyl group in addition to the α,β-diol structure, and examples thereof include glycerol, tartaric acid, arabinitol, xylitol, xylonic acid, glucaric acid, gluconic acid, glucitol, mannitol, fructose, and galactose. Among these, tartaric acid, glucaric acid, gluconic acid, glucitol, and mannitol are particularly preferred, and glucitol is the most preferred, from the viewpoint that it is easy to control the molecular weight during esterification when there are two hydroxyl groups and/or carboxyl groups remaining after acetalization.

Examples of aldehyde compounds include formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, butanal, pentanal, hexanal, heptanal, octanal, nonanal, decanal, acrolein, furfural, benzaldehyde, and cinnamaldehyde. From the viewpoint of ease of acetalization reaction, formaldehyde, acetaldehyde, and furfural are preferred.

Examples of ketone compounds include acetone, methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, cyclohexanone, isophorone, acetophenone, benzophenone, etc., and acetone and methyl ethyl ketone are preferred due to the ease of the acetalization reaction.

Examples of acetal compounds include 2,2-dimethoxypropane, 2,2-diethoxypropane, 3,3-dimethoxypentane, dimethyl acetal, etc., with 2,2-dimethoxypropane being preferred due to the ease of the acetalization reaction.

Among at least one compound selected from the group consisting of aldehyde compounds, ketone compounds, and acetal compounds, acetone and 2,2-dimethoxypropane are most preferred from the viewpoints of ease of the acetalization reaction and the hygroscopicity of the resulting polyester resin.

The aldehyde compounds, ketone compounds, and acetal compounds may each be used alone or in combination of two or more.

An example of a carboxylic acid compound having a 1,3-dioxolane structure is a compound represented by the general formula (2).

In the general formula (2), R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group.
Examples of the alkyl group include linear or branched alkyl groups having 1 to 18 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, and a decyl group.

Specific examples of the carboxylic acid compound having a 1,3-dioxolane structure include 1,3-dioxolane-4,5-dicarboxylic acid, 2-methyl-1,3-dioxolane-4,5-dicarboxylic acid, 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid, 2-methyl-2-ethyl-1,3-dioxolane-4,5-dicarboxylic acid, 2,2-diethyl-1,3-dioxolane-4,5-dicarboxylic acid, 2-methyl-2-isobutyl-1,3-dioxolane-4,5-dicarboxylic acid, 2,2-dipropyl-1,3-dioxolane-4,5-dicarboxylic acid, 2,2-dibutyl-1,3-dioxolane-4,5-dicarboxylic acid and 2,2-diheptadecyl-1,3-dioxolane-4,5-dicarboxylic acid. One type may be used alone, or two or more types may be used in combination. The carboxylic acid compound having a 1,3-dioxolane structure may be a carboxylic acid anhydride or a lower alkyl (having 1 to 4 carbon atoms) ester (such as a methyl ester, an ethyl ester, or an isopropyl ester).
From the viewpoint of controlling the glass transition temperature of the resulting polyester, among the carboxylic acid compounds having a 1,3-dioxolane structure, a compound in which R ₁ and R ₂ in general formula (2) are linear alkyl groups having 1 to 18 carbon atoms is preferred, and 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid is more preferred.

Examples of the alcohol having a 1,3-dioxolane structure include 2,3-O-isopropylidene-L-threitol, 1,2-O-isopropylidene-L-threitol, 1,2:3,4-di-O-isopropylidene glucitol, 3,4:5,6-di-O-isopropylidene glucitol, 1,2:5,6-di-O-isopropylidene glucitol, 1,2:3,4-di-O-isopropylidene mannitol, and 1,2:5,6-di-O-isopropylidene mannitol. One type may be used alone, or two or more types may be used in combination.
Among the alcohols having a 1,3-dioxolane structure, from the viewpoint of controlling the glass transition temperature of the resulting polyester, at least one selected from the group consisting of 3,4:5,6-di-O-isopropylidene glucitol, 1,2:5,6-di-O-isopropylidene glucitol, 1,2:3,4-di-O-isopropylidenemannitol, and 1,2:5,6-di-O-isopropylidenemannitol is preferred, and 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol are more preferred.

From the viewpoint of the moist heat resistance storage property and low temperature fixability of the toner, the total amount of the carboxylic acid compound having a 1,3-dioxolane structure and the alcohol having a 1,3-dioxolane structure is preferably 10 to 100 mol % of the total amount of the carboxylic acid component and the alcohol component.

Furthermore, the content of the carboxylic acid compound having a 1,3-dioxolane structure is preferably 10 to 100 mol % in the carboxylic acid component from the viewpoint of the low-temperature fixability and moist heat resistance storage property of the toner.

The content of the alcohol having a 1,3-dioxolane structure in the alcohol component is preferably 10 to 100 mol % from the viewpoint of the low-temperature fixability and humidity and heat resistance storage properties of the toner.

The polyester resin for toner of the present invention may contain, as a raw material monomer, a carboxylic acid compound having at least a 1,3-dioxolane structure and/or an alcohol having a 1,3-dioxolane structure, and may also contain a conventionally known alcohol component and/or carboxylic acid component.
The alcohol component includes a diol (g) and a trihydric or higher polyol (h).

Examples of the diol (g) include alkylene glycols having 2 to 36 carbon atoms, alkylene ether glycols having 4 to 36 carbon atoms, alicyclic diols having 4 to 36 carbon atoms, alkylene oxide adducts of alkylene glycols or alicyclic diols, alkylene oxide adducts of bisphenols, polylactone diols, and polybutadiene diols.
Specific examples of alkylene glycols having 2 to 36 carbon atoms include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, octanediol, decanediol, dodecanediol, tetradecanediol, neopentyl glycol, and 2,2-diethyl-1,3-propanediol.
Specific examples of alkylene ether glycols having 4 to 36 carbon atoms include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol.
Specific examples of the alicyclic diol having 4 to 36 carbon atoms include 1,4-cyclohexanedimethanol and hydrogenated bisphenol A.
In the alkylene oxide adduct of an alkylene glycol or an alicyclic diol, examples of the alkylene glycol or alicyclic diol include those mentioned above, and examples of the alkylene oxide (hereinafter abbreviated as AO) adduct include an ethylene oxide (hereinafter abbreviated as EO), a propylene oxide (hereinafter abbreviated as PO) adduct, and a butylene oxide (hereinafter abbreviated as BO) adduct, etc.
Examples of the AO adducts of bisphenol include AO (EO, PO, BO, etc.) adducts (molar number of addition: 2 to 30) of bisphenol A, bisphenol F, bisphenol S, etc.
The polylactone diol includes poly-ε-caprolactone diol.

As the diol (g), in addition to the above diols having no functional groups other than hydroxyl groups, diols (g1) having other functional groups may be used.
Examples of (g1) include diols having a carboxyl group, diols having a sulfonic acid group or a sulfamic acid group, and salts thereof.
The diol having a carboxyl group may be a dialkylolalkanoic acid having 6 to 24 carbon atoms, specifically 2,2-dimethylolpropionic acid (DMPA), 2,2-dimethylolbutanoic acid, 2,2-dimethylolheptanoic acid, 2,2-dimethyloloctanoic acid, etc.
Examples of diols having a sulfonic acid group or a sulfamic acid group include 3-(2,3-dihydroxypropoxy)-1-propanesulfonic acid, sulfoisophthalic acid di(ethylene glycol) ester, sulfamic acid diol, and bis(2-hydroxyethyl)phosphate.

Preferred diols (g) are alkylene glycols having 2 to 12 carbon atoms, diols having a carboxyl group, AO adducts of bisphenols, and combinations of these.

Examples of the tri- or higher hydric polyol (h) include tri- or higher hydric polyhydric aliphatic alcohols having 3 to 36 carbon atoms, AO adducts of polyhydric aliphatic alcohols (number of moles added: 2 to 120), AO adducts of trisphenols (e.g., trisphenol PA) (number of moles added: 2 to 30), AO adducts of novolak resins (e.g., phenol novolak, cresol novolak) (number of moles added: 2 to 30), and acrylic polyols [e.g., copolymers of hydroxyethyl (meth)acrylate and other vinyl monomers].
Examples of the polyhydric aliphatic alcohol having 3 to 36 carbon atoms and having a valence of 3 or more include alkane polyols and their intramolecular or intermolecular dehydration products, as well as sugars (such as sucrose) and their methyl glucosides.
Specific examples of alkane polyols and their intramolecular or intermolecular dehydration products include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, sorbitan, and polyglycerin.

Preferred as the trihydric or higher polyol (h) are trihydric or higher polyhydric aliphatic alcohols and AO adducts of novolac resins, and more preferred are AO adducts of novolac resins.

Examples of the carboxylic acid component include dicarboxylic acids (i), trivalent or higher polycarboxylic acids (j), and their acid anhydrides or lower alkyl esters.

Examples of the dicarboxylic acid (i) include alkane dicarboxylic acids having 4 to 36 carbon atoms, alkenyl succinic acids, alicyclic dicarboxylic acids having 6 to 40 carbon atoms, alkene dicarboxylic acids having 4 to 36 carbon atoms, and aromatic dicarboxylic acids having 8 to 36 carbon atoms.
Examples of the alkanedicarboxylic acid having 4 to 36 carbon atoms include succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, and decylsuccinic acid.
Examples of the alkenylsuccinic acid include dodecenylsuccinic acid, pentadecenylsuccinic acid, and octadecenylsuccinic acid.
Examples of the alicyclic dicarboxylic acid having 6 to 40 carbon atoms include dimer acid (dimerized linoleic acid).
Examples of the alkene dicarboxylic acid having 4 to 36 carbon atoms include maleic acid, fumaric acid, and citraconic acid.
Examples of the aromatic dicarboxylic acid having 8 to 36 carbon atoms include phthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid.
Of these dicarboxylic acids (i), preferred are alkanedicarboxylic acids having 4 to 36 carbon atoms and aromatic dicarboxylic acids having 8 to 36 carbon atoms, and more preferred are alkanedicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms.

Examples of trivalent or higher polycarboxylic acids (j) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (e.g., trimellitic acid, pyromellitic acid) and aliphatic (including alicyclic) tricarboxylic acids having 6 to 36 carbon atoms (e.g., hexanetricarboxylic acid, decanetricarboxylic acid, etc.).

Among these trivalent or higher polycarboxylic acids (j), preferred are aromatic polycarboxylic acids having 9 to 20 carbon atoms, and more preferred are trimellitic acid and pyromellitic acid.

As the dicarboxylic acid (i) or the trivalent or higher polycarboxylic acid (j), the above-mentioned acid anhydrides or lower alkyl esters having 1 to 4 carbon atoms (methyl esters, ethyl esters, isopropyl esters, etc.) may be used.

The reaction ratio of the alcohol component and the carboxylic acid component, expressed as the molar ratio [OH]/[COOH] of the hydroxyl group [OH] to the carboxyl group [COOH], is preferably 1/5 to 2/1, more preferably 1/4 to 1.5/1, and particularly preferably 1/3 to 1/1.3.
In order to bring the carboxyl group content into the above-mentioned preferred range, a polyester having an excess of hydroxyl groups may be treated with a polycarboxylic acid.

The polyester resin can be produced by a known production method.
For example, a method can be mentioned in which a carboxylic acid component containing a carboxylic acid compound having at least a 1,3-dioxolane structure and/or an alcohol component containing an alcohol having a 1,3-dioxolane structure is used as raw material monomers, and the carboxylic acid component and the alcohol component are subjected to a polycondensation reaction in an inert gas (such as nitrogen gas) atmosphere at a reaction temperature of preferably 150 to 280° C. for a reaction time of preferably 30 minutes or longer.

In addition, when terephthalic acid is used as the carboxylic acid component in this reaction, a terephthalic acid component derived from PET (polyethylene terephthalate) may be used in place of terephthalic acid or may be mixed together with terephthalic acid. Similarly, when ethylene glycol is used as the alcohol component, an ethylene glycol component derived from PET (polyethylene terephthalate) may be used in place of ethylene glycol or may be mixed together with ethylene glycol.

In this case, an esterification catalyst can be used as necessary.
Esterification catalysts include tin-containing catalysts, antimony trioxide, titanium-containing catalysts, zirconium-containing catalysts, zinc acetate, and the like.
Specifically, the tin-containing catalyst may be dibutyltin oxide.
Examples of the titanium-containing catalyst include titanium alkoxides, potassium oxalate titanate, titanium terephthalate, the catalysts described in JP-A-2006-243715 (titanium dihydroxybis(triethanolaminate), titanium monohydroxytris(triethanolaminate), and intramolecular polycondensates thereof, etc.), and the catalysts described in JP-A-2007-11307 (titanium tributoxyterephthalate, titanium triisopropoxyterephthalate, titanium diisopropoxyditerephthalate, etc.).
Zirconium-containing catalysts include zirconyl acetate.

Among the esterification catalysts, titanium-containing catalysts are preferred from the viewpoint of the electrostatic properties of the polyester resin, and more preferred are the catalysts described in JP-A-2006-243715 and JP-A-2007-11307.

When the polyester resin contains a constituent unit of an organic acid metal salt, this resin can be obtained, for example, by synthesizing a polyester having a COOH group (an acid value of preferably 1 to 100 mgKOH/g, more preferably 5 to 50 mgKOH/g) and converting at least a part of the COOH groups into a salt of at least one metal selected from Al, Ti, Cr, Mn, Fe, Zn, Ba, and Zr.
The metal salt can be obtained, for example, by reacting a polyester having a COOH group with a hydroxide of the corresponding metal.

In the present invention, the number average molecular weight (Mn) and the weight average molecular weight (Mw) can be measured by gel permeation chromatography (GPC) under the following conditions.
Apparatus: "HLC-8120" [manufactured by Tosoh Corporation]
Column: 2 "TSK GEL GMH6" [manufactured by Tosoh Corporation] Measurement temperature: 40°C
Sample solution: 0.25% by weight tetrahydrofuran solution (undissolved matter was removed by filtration using a glass filter)
Solution injection volume: 100μl
Detector: Refractive index detector Reference material: 12 types of standard polystyrene (TSKstandard POLYSTYRENE) (molecular weight: 500, 1,050, 2,800, 5,970, 9,100, 18,100, 37,900, 96,400, 190,000, 355,000, 1,090,000, 2,890,000) [manufactured by Tosoh Corporation]

From the viewpoint of low-temperature fixability and humidity and heat resistance storage stability, the number average molecular weight (Mn) of the polyester resin is preferably 1,000 to 10,000, and more preferably 1,500 to 8,000.

The weight average molecular weight (Mw) of the polyester resin is preferably 2,000 to 50,000, and more preferably 3,000 to 30,000, from the viewpoints of low-temperature fixability and humidity and heat resistance storage stability.

The acid value of the polyester resin is preferably 0 to 40 mgKOH/g from the viewpoint of resistance to moist heat storage. The acid value can be measured by the method specified in JIS K0070.

The hydroxyl value of the polyester resin is preferably 20 to 80 mgKOH/g from the viewpoint of humidity and heat resistance storage. The hydroxyl value can be measured by the method specified in JIS K0070.

The glass transition temperature (Tg) of the polyester resin is preferably from 40 to 120°C, and more preferably from 50 to 80°C.
In the present invention, Tg can be measured by the method (DSC) specified in ASTM D3418-82 using "DSC20, SSC/580" [manufactured by Seiko Denshi Kogyo Co., Ltd.].

The toner of the present invention is a toner containing the above-mentioned polyester resin for toner.
By using a binder resin containing the polyester resin for toner of the present invention, a toner having excellent low-temperature fixing property and humidity and heat storage resistance can be obtained.

The toner of the present invention may contain other resins in addition to the polyester resins described above. Any known resins may be used as the other resins, and specific examples of such resins include polyester resins other than the polyester resins described above, vinyl resins, polyurethane resins, epoxy resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins.
Preferable examples of the other resins include polyester resins other than the above polyester resins, vinyl resins, polyurethane resins, epoxy resins, and combinations of these resins, and more preferably, combinations of polyester resins other than the above polyester resins and vinyl resins.

When the other resin is a polyester resin other than the polyester resin of the present invention, the polyester resin may be a crystalline polyester resin or an amorphous polyester resin, and the same conventionally known alcohol components and/or carboxylic acid components as exemplified for the polyester resin of the present invention can be used. Preferred alcohol components and carboxylic acid components are the same as those for the polyester resin of the present invention described above, and the polyester resin can be produced in the same manner, except that an alcohol and a carboxylic acid compound having a 1,3-dioxolane structure are not used.
In the present invention, "crystalline" refers to a state in which a differential scanning calorimetry (DSC) curve has a maximum and an endothermic peak during the temperature rise process of the differential scanning calorimetry curve obtained by DSC measurement, whereas "amorphous" refers to a state in which the DSC curve does not have an endothermic peak.

When the other resin is a vinyl resin, the vinyl resin is a polymer obtained by homopolymerizing or copolymerizing a vinyl monomer. Examples of the vinyl monomer include the following (1) to (10).
(1) Vinyl Hydrocarbons Examples of the vinyl hydrocarbons include (1-1) aliphatic vinyl hydrocarbons, (1-2) alicyclic vinyl hydrocarbons, and (1-3) aromatic vinyl hydrocarbons.
(1-1) Aliphatic Vinyl Hydrocarbons Examples of the aliphatic vinyl hydrocarbons include alkenes and alkadienes.
Specific examples of alkenes include ethylene, propylene, and α-olefins.
Specific examples of alkadienes include butadiene, isoprene, 1,4-pentadiene, 1,6-heptadiene, and 1,7-octadiene.
(1-2) Alicyclic Vinyl Hydrocarbons Examples of alicyclic vinyl hydrocarbons include mono- or di-cycloalkenes and alkadienes, and specific examples thereof include (di)cyclopentadiene and terpene.
(1-3) Aromatic Vinyl Hydrocarbons Examples of aromatic vinyl hydrocarbons include styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and/or alkenyl) substituted derivatives, and specific examples thereof include α-methylstyrene, 2,4-dimethylstyrene, and vinylnaphthalene.

(2) Carboxylic Group-Containing Vinyl Monomer and Salts Thereof Examples of the carboxyl group-containing vinyl monomer and salts thereof include unsaturated monocarboxylic acids (salts), unsaturated dicarboxylic acids (salts), and anhydrides (salts), and monoalkyl (C1-24) esters or salts thereof, each having 3 to 30 carbon atoms.
Specific examples thereof include carboxyl group-containing vinyl monomers such as (meth)acrylic acid, (anhydride) maleic acid, maleic acid monoalkyl esters, fumaric acid, fumaric acid monoalkyl esters, crotonic acid, itaconic acid, itaconic acid monoalkyl esters, itaconic acid glycol monoether, citraconic acid, citraconic acid monoalkyl esters, and cinnamic acid, and metal salts thereof.

In the present invention, the term "(salt)" refers to a salt of a compound.
For example, an unsaturated monocarboxylic acid (salt) means an unsaturated monocarboxylic acid or a salt thereof.

In the present invention, "(meth)acrylic" means methacryl or acrylic.
In the present invention, "(meth)acryloyl" means methacryloyl or acryloyl.
In the present invention, "(meth)acrylate" means methacrylate or acrylate.

(3) Sulfone Group-Containing Vinyl Monomers, Vinyl Sulfate Monoesters, and Salts Thereof Examples of the sulfone group-containing vinyl monomers, vinyl sulfate monoesters, and salts thereof include alkene sulfonic acids (salts) having 2 to 14 carbon atoms, alkyl sulfonic acids (salts) having 2 to 24 carbon atoms, sulfo(hydroxy)alkyl-(meth)acrylates (salts), sulfo(hydroxy)alkyl-(meth)acrylamides (salts), and alkylaryl sulfosuccinic acids (salts).
Specifically, an example of an alkene sulfonic acid having 2 to 14 carbon atoms is vinyl sulfonic acid (salt), etc., an example of an alkyl sulfonic acid (salt) having 2 to 24 carbon atoms is α-methylstyrene sulfonic acid (salt), etc., and an example of a sulfo(hydroxy)alkyl-(meth)acrylate (salt) or (meth)acrylamide (salt) is sulfopropyl(meth)acrylate (salt), sulfuric acid ester (salt), or a sulfonic acid group-containing vinyl monomer (salt), etc.

(4) Phosphate-containing vinyl monomers and their salts:
Examples of the phosphoric acid group-containing vinyl monomer and its salt include (meth)acryloyloxyalkyl (C1-24) phosphoric acid monoester (salt) and (meth)acryloyloxyalkyl (C1-24) phosphonic acid (salt).
Specific examples of the (meth)acryloyloxyalkyl (having 1 to 24 carbon atoms) phosphate monoester (salt) include 2-hydroxyethyl (meth)acryloyl phosphate (salt) and phenyl-2-acryloyloxyethyl phosphate (salt).
Specific examples of the (meth)acryloyloxyalkyl (C1 to C24)phosphonic acid (salt) include 2-acryloyloxyethylphosphonic acid (salt).

Examples of the salts of (2) to (4) above include alkali metal salts (sodium salts, potassium salts, etc.), alkaline earth metal salts (calcium salts, magnesium salts, etc.), ammonium salts, amine salts, and quaternary ammonium salts.

(5) Hydroxyl Group-Containing Vinyl Monomers Examples of hydroxyl group-containing vinyl monomers include hydroxystyrene, N-methylol (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, (meth)allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl alcohol, 2-hydroxyethyl propenyl ether, and sucrose allyl ether.

(6) Nitrogen-Containing Vinyl Monomers Examples of the nitrogen-containing vinyl monomers include (6-1) amino group-containing vinyl monomers, (6-2) amide group-containing vinyl monomers, (6-3) nitrile group-containing vinyl monomers, (6-4) quaternary ammonium cation group-containing vinyl monomers, and (6-5) nitro group-containing vinyl monomers.
(6-1) Examples of amino group-containing vinyl monomers include aminoethyl (meth)acrylate.
(6-2) Examples of the amide group-containing vinyl monomer include (meth)acrylamide and N-methyl(meth)acrylamide.
(6-3) Examples of nitrile group-containing vinyl monomers include (meth)acrylonitrile, cyanostyrene, and cyanoacrylate.
(6-4) Examples of the quaternary ammonium cation group-containing vinyl monomer include quaternized products of tertiary amine group-containing vinyl monomers such as dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylamide, diethylaminoethyl (meth)acrylamide, and diallylamine (which are quaternized with a quaternizing agent such as methyl chloride, dimethyl sulfate, benzyl chloride, or dimethyl carbonate).
(6-5) Nitro group-containing vinyl monomers include nitrostyrene and the like.

(7) Epoxy Group-Containing Vinyl Monomers Examples of epoxy group-containing vinyl monomers include glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and p-vinylphenylpropylene oxide.

(8) Halogen-Containing Vinyl Monomers Examples of halogen-containing vinyl monomers include vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluoroethylene, fluoroacrylate, tetrafluorostyrene, and chloroprene.

(9) Alkyl esters of (meth)acrylic acid, vinyl esters, vinyl (thio) ethers, vinyl ketones (9-1) Examples of alkyl esters of (meth)acrylic acid include (meth)acrylic acid esters having an alkyl group having 1 to 50 carbon atoms [methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, eicosyl (meth)acrylate, behenyl (meth)acrylate, etc.)].
(9-2) Examples of vinyl esters include vinyl acetate, vinyl butyrate, vinyl propionate, and vinyl butyrate.
(9-3) Examples of vinyl (thio)ethers include vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, vinyl butyl ether, vinyl 2-ethylhexyl ether, vinyl phenyl ether, vinyl 2-methoxyethyl ether, methoxybutadiene, vinyl 2-butoxyethyl ether, 3,4-dihydro-1,2-pyran, 2-butoxy-2'-vinyloxydiethyl ether, vinyl 2-ethylmercaptoethyl ether, acetoxystyrene, and phenoxystyrene.
(9-4) Examples of vinyl ketones include vinyl methyl ketone, vinyl ethyl ketone, and vinyl phenyl ketone.

(10) Other Vinyl Monomers Examples of other vinyl monomers include tetrafluoroethylene, fluoroacrylate, isocyanatoethyl (meth)acrylate, and m-isopropenyl-α,α-dimethylbenzyl isocyanate.

In the synthesis of the vinyl resin, the above vinyl monomers (1) to (10) may be used alone or in combination of two or more.
As the vinyl resin, from the viewpoints of particle size distribution and electrostatic chargeability, styrene-(meth)acrylic acid ester copolymers and (meth)acrylic acid ester copolymers are preferred, and styrene-(meth)acrylic acid ester copolymers are more preferred.

The toner of the present invention may contain various known additives such as colorants, release agents, charge control agents, and flow agents, if necessary.

The colorant preferably contains at least one selected from the group consisting of a black colorant, a blue colorant, a red colorant and a yellow colorant. As the colorant, any dye, pigment or the like that is used as a toner colorant can be used.
Specific examples thereof include carbon black, iron black, Sudan Black SM, Fast Yellow G, Benzidine Yellow, Solvent Yellow (21, 77, 114, etc.), Pigment Yellow (12, 14, 17, 83, etc.), India Fast Orange, Irgasin Red, Paranitoaniline Red, Toluidine Red, Solvent Red (17, 49, 128, 5, 13, 22, 48.2, etc.), Disperse Red, Carmine FB, Pigment Orange R, Lake Red 2G, Rhodamine FB, Rhodamine B Lake, Methyl Violet B Lake, Phthalocyanine Blue, Solvent Blue (25, 94, 60, 15.3, etc.), Pigment Blue, Brilliant Green, Phthalocyanine Green, Oil Yellow GG, Kayaset YG, Orasol Brown B, and Oil Pink OP. If necessary, magnetic powder (powders of ferromagnetic metals such as iron, cobalt and nickel, and compounds such as magnetite, hematite and ferrite) may be contained to function as a colorant.
The content of the colorant is preferably 1 to 40 parts by weight, more preferably 2 to 15 parts by weight, based on 100 parts by weight of the total of the polyester resin of the present invention and the other resins. When a magnetic powder is used, the content of the magnetic powder is preferably 20 to 150 parts by weight, more preferably 30 to 120 parts by weight, based on 100 parts by weight of the total of the polyester resin of the present invention and the other resins.

Examples of release agents include natural waxes (beeswax, carnauba wax, montan wax, etc.), petroleum waxes (paraffin wax, microcrystalline wax, petrolatum, etc.), synthetic waxes (Fischer-Tropsch wax, polyethylene wax, polypropylene wax, oxidized polyethylene wax, oxidized polypropylene wax, etc.), and synthetic ester waxes (fatty acid esters synthesized from fatty acids having 10 to 30 carbon atoms and alcohols having 10 to 30 carbon atoms, etc.), and it is preferable to contain one or more types selected from the group consisting of these release agents. The content of the release agent is preferably 0 to 30% by weight, more preferably 0.5 to 20% by weight, and even more preferably 1 to 10% by weight, based on 100 parts by weight of the total of the polyester resin of the present invention and other resins.

When using the above-mentioned release agent, modified wax may be used in combination if necessary. The modified wax is a release agent to which a vinyl polymer chain has been grafted. The release agents used in the modified wax include the same as those described above, and the preferred ones are also the same. Examples of the vinyl monomers constituting the vinyl polymer chain of the modified wax include styrene and methacrylic acid esters. The vinyl polymer chain may be a homopolymer or copolymer of a vinyl monomer. The content of the modified wax is preferably 0 to 15% by weight, more preferably 0.5 to 10% by weight, and even more preferably 1 to 5% by weight, based on 100 parts by weight of the total of the polyester resin of the present invention and other resins.

The charge control agent may be either a positively charged charge control agent or a negatively charged charge control agent, and examples thereof include nigrosine dyes, triphenylmethane dyes containing a tertiary amine as a side chain, quaternary ammonium salts, polyamine resins, imidazole derivatives, polymers containing a quaternary ammonium base, metal-containing azo dyes, copper phthalocyanine dyes, metal salicylic acid salts, boron complexes of benzilic acid, polymers containing sulfonic acid groups, fluorine-containing polymers, and halogen-substituted aromatic ring-containing polymers. The content of the charge control agent may be 0 to 20% by weight, preferably 0.1 to 10% by weight, and more preferably 0.5 to 7.5% by weight, based on 100 parts by weight of the total of the polyester resin of the present invention and other resins.

Examples of the fluidizing agent include silica, titania, alumina, fatty acid metal salts, silicone resin particles, and fluororesin particles, and two or more of them may be used in combination. From the viewpoint of the chargeability of the toner, silica is preferred. From the viewpoint of the transferability of the toner, the silica is preferably hydrophobic. The content of the fluidizing agent may be 0 to 10% by weight, preferably 0 to 5% by weight, and more preferably 0.1 to 4% by weight, based on 100 parts by weight of the toner of the present invention.

The total weight of additives such as colorants, release agents, charge control agents, and flow agents may be 3 to 70% by weight, preferably 4 to 58% by weight, and more preferably 5 to 50% by weight, based on the weight of the toner.

There are no particular limitations on the method of producing the toner, and it may be obtained by a known kneading and grinding method, a suspension polymerization method described in JP-B-36-10231, JP-A-59-53856, and JP-A-59-61842, an emulsion polymerization method represented by a soap-free polymerization method in which a toner is produced by directly polymerizing a monomer in the presence of a water-soluble polymerization initiator that is soluble in the monomer, an interfacial polymerization method such as a microcapsule manufacturing method, an in-site polymerization method, a coacervation method in which at least one type of fine particles are aggregated to obtain a toner of a desired particle size as disclosed in JP-A-62-106473 and JP-A-63-186253, a dispersion polymerization method characterized by monodispersion, a dissolution suspension method in which necessary resins are dissolved in a non-water-soluble organic solvent and then resin particles are formed in an aqueous medium, or an ester elongation polymerization method, or it may be produced by a method of dispersing in carbon dioxide in a supercritical state.

As the aqueous medium in the present invention, any liquid containing water as an essential component can be used without limitation, and examples of the aqueous medium that can be used include water, an aqueous solution of an organic solvent, an aqueous solution of a surfactant (s), an aqueous solution of a water-soluble polymer (t), and mixtures thereof, as described below.
As a method for stably forming a dispersion containing the polyester resin of the present invention in an aqueous medium, there may be mentioned a method in which the polyester resin is added to an aqueous medium and dispersed by shear force.
When the other resin is used, the polyester resin or the like and the other resin may be mixed in advance and dispersed in the aqueous medium.
When other resins are used as fine particles, the fine particles of the resin are not particularly limited as long as they can form fine particles in an aqueous medium and can be adsorbed to the polyester resin of the present invention.

The method for producing resin fine particles is not particularly limited, but includes the following methods [1] and [2].
[1] In the case of vinyl resins, a method of directly producing a dispersion of fine resin particles by a polymerization reaction such as suspension polymerization, emulsion polymerization, seed polymerization or dispersion polymerization using a monomer as a starting material.
[2] In the case of polyaddition or condensation resins such as polyester resins, polyurethane resins, and epoxy resins, a precursor (monomer, oligomer, etc.) or a solvent solution thereof is dispersed in a medium in the presence of a suitable dispersant, and then heated or a curing agent is added to harden the precursor, thereby producing a fine particle dispersion of the resin.

In the above method [1] or [2], the emulsifier or dispersant used in combination may be a known surfactant (s) or a water-soluble polymer (t) as described below. In addition, an organic solvent or the like as described below may be used in combination as an emulsifying or dispersing aid.

In the present invention, other raw materials such as colorants, release agents, modified waxes, and charge control agents do not necessarily need to be mixed in the aqueous medium when forming particles, but may be added after the particles are formed. For example, after forming particles that do not contain colorants, colorants can be added using a known dyeing method.

The dispersion method is not particularly limited, but known equipment such as low-speed shear type, high-speed shear type, friction type, high-pressure jet type, and ultrasonic type can be applied. A high-speed shear type is preferred in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shear type disperser is used, the rotation speed is not particularly limited, but is generally 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is generally 0.1 to 5 minutes.
Examples of the dispersion device include batch-type emulsifiers such as Homogenizer (manufactured by IKA Corporation), Polytron (manufactured by Kinematica Corporation), and TK Auto Homo Mixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), Ebara Milder (manufactured by Ebara Corporation), TK Filmix, TK Pipeline Homo Mixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), Colloid Mill (manufactured by Kobelco Pantech Co., Ltd.), Ultra Visco Mill (manufactured by Imex), Slasher, and Trigonal Wet Fine Grinding Mill (manufactured by Mitsui Miike Kakoki Co., Ltd.), etc. Examples of such emulsifiers include continuous emulsifiers such as Ebara Microfluidizer (manufactured by Ebara Microfluidizer Co., Ltd.), Capitron (manufactured by Eurotech Co., Ltd.), Fine Flow Mill (manufactured by Pacific Machinery Co., Ltd.), high pressure emulsifiers such as Microfluidizer (manufactured by Mizuho Kogyo Co., Ltd.), Nanomizer (manufactured by Nanomizer Co., Ltd.), APV Gaulin (manufactured by Gaulin Co., Ltd.), membrane emulsifiers such as Membrane Emulsifier (manufactured by Reika Kogyo Co., Ltd.), vibration type emulsifiers such as Vibro Mixer (manufactured by Reika Kogyo Co., Ltd.), ultrasonic emulsifiers such as Ultrasonic Homogenizer (manufactured by Branson Co., Ltd.), etc. Among these, from the viewpoint of particle size uniformity, APV Gaulin, homogenizer, TK Auto Homo Mixer, Ebara Milder, TK Filmix and TK Pipeline Homo Mixer are preferred.

When dispersing the polyester resin of the present invention in an aqueous medium, the polyester resin is preferably liquid. If the polyester resin is solid at room temperature, it may be dispersed in a liquid state at a high temperature equal to or higher than the melting point, or an organic solvent solution of the polyester resin may be used. Using an organic solvent is preferable in that the particle size distribution is sharper.

Examples of the organic solvent include aromatic hydrocarbon solvents, aliphatic or alicyclic hydrocarbon solvents, halogenated solvents, ester or ester ether solvents, ether solvents, ketone solvents, alcohol solvents, amide solvents, sulfoxide solvents, heterocyclic compound solvents, and mixed solvents of two or more of these.
Specific examples of organic solvents include aromatic hydrocarbon solvents (toluene, xylene, ethylbenzene, tetralin, etc.); aliphatic or alicyclic hydrocarbon solvents (n-hexane, n-heptane, mineral spirits, cyclohexane, etc.); halogenated solvents such as methyl chloride, methyl bromide, methyl iodide, methylene dichloride, carbon tetrachloride, trichloroethylene, and perchloroethylene; ester or ester ether solvents such as ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, and ethyl cellosolve acetate; diethyl ether, tetrahydrofuran, dioxane, ethyl cellosolve, butyl ether ... Examples of the organic solvent include ether solvents such as Rosolve and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone and cyclohexanone; alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2-ethylhexyl alcohol and benzyl alcohol; amide solvents such as dimethylformamide and dimethylacetamide; sulfoxide solvents such as dimethylsulfoxide, heterocyclic compound solvents such as N-methylpyrrolidone, and mixed solvents of two or more of these. Among the above organic solvents, volatile ones having a boiling point of less than 100° C. are preferred. Preferred organic solvents include ethyl acetate, acetone, methyl ethyl ketone, and the like.

When dispersing the polyester resin of the present invention in an aqueous medium, a known surfactant (s) can be used as an emulsifier or dispersant to be used in combination. The use of surfactant (s) is preferred in that it makes it easier to reduce the volume average particle size of the toner.

The surfactant (s) is not particularly limited, and examples thereof include anionic surfactants (s-1), cationic surfactants (s-2), amphoteric surfactants (s-3), and nonionic surfactants (s-4). The surfactant (s) may be a combination of two or more surfactants.

Examples of the anionic surfactant (s-1) include carboxylic acids or their salts, sulfate salts, salts of carboxymethyl compounds, sulfonates, and phosphate salts.
Examples of the cationic surfactant (s-2) include quaternary ammonium salt type surfactants and amine salt type surfactants.
Examples of the amphoteric surfactant (s-3) include carboxylate-type amphoteric surfactants, sulfate-type amphoteric surfactants, sulfonate-type amphoteric surfactants, and phosphate-type amphoteric surfactants.
Examples of the nonionic surfactant (s-4) include AO-addition type nonionic surfactants and polyhydric alcohol type nonionic surfactants.
Specific examples of these surfactants (s) include those described in JP-A No. 2002-284881.

The amount of surfactant (s) used per 100 parts by weight of water as the aqueous medium is preferably 0 to 300 parts by weight, more preferably 0.001 to 10 parts by weight, and particularly preferably 0.01 to 5 parts by weight.

When dispersing the polyester resin of the present invention in an aqueous medium, a known water-soluble polymer (t) can be used as an emulsifier or dispersant to be used in combination. The use of a water-soluble polymer (t) is preferable in that the volume average particle size of the toner is smaller and the particle size distribution (volume average particle size/number average particle size) is likely to be smaller.

Examples of the water-soluble polymer (t) include cellulose compounds (e.g., methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, ethylhydroxyethyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, and saponified products thereof, etc.), gelatin, starch, dextrin, gum arabic, chitin, chitosan, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, polyethyleneimine, polyacrylamide, acrylic acid (salt)-containing polymers (sodium polyacrylate, potassium polyacrylate, ammonium polyacrylate, partially neutralized polyacrylic acid with sodium hydroxide, and sodium acrylate-acrylic acid ester copolymers, etc.), sodium hydroxide (partially) neutralized styrene-maleic anhydride copolymers, and water-soluble polyurethanes (polyethylene glycol, and reaction products of polycaprolactone diol, etc., with polyisocyanates, etc.).

The amount of water-soluble polymer (t) used per 100 parts by weight of water as the aqueous medium is preferably 0 to 5 parts by weight.

The polyester resin of the present invention is a toner raw material that is fixed to a support (paper, polyester film, etc.) by a copier, printer, etc. to become a recording material. As a method for fixing to a support, a known hot roll fixing method, flash fixing method, etc. can be applied.

The toner of the present invention is used for developing electrostatic images or magnetic latent images in electrophotography, electrostatic recording, electrostatic printing, etc. More specifically, the present invention relates to a toner used for developing electrostatic images or magnetic latent images that is particularly suitable for full color.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. In the following, "parts" refers to parts by weight unless otherwise specified.

The physical properties of the polyester resin and toner were measured using the following methods.

[Measurement method]
<Acid value and hydroxyl value>
The measurement was performed according to the method specified in JIS K0070, except that the measurement solvent for the acid value was a mixed solvent of acetone, methanol, and toluene (weight ratio of acetone:methanol:toluene=12.5:12.5:75), and the measurement solvent for the hydroxyl value was THF.

<Number average molecular weight (Mn) and weight average molecular weight (Mw)>
The resin was dissolved in tetrahydrofuran (THF), and the resulting solution was used as a sample solution for measurement by gel permeation chromatography (GPC) under the following conditions.
Apparatus: HLC-8120 (manufactured by Tosoh Corporation)
Column: 2 TSK GEL GMH6 columns (manufactured by Tosoh Corporation)
Measurement temperature: 40°C
Sample solution: 0.25% by weight THF solution (undissolved matter was removed by filtration using a glass filter)
Solution injection volume: 100μL
Detector: Refractive index detector Reference material: Standard polystyrene (TSKstandard POLYSTYRENE)

<Solid content and volatile content of dispersion>
Taking care not to cause precipitation of toner or resin fine particles, 2.00 g of the sample before drying was weighed out and dried at 120° C. for 1 hour. The dried sample was removed and its weight was measured to two decimal places. The solid content concentration (wt %) was calculated from (weight of sample after drying/weight of sample before drying) x 100, and the volatile content (wt %) was calculated from {(weight of sample before drying-weight of sample after drying)/weight of sample before drying} x 100.

<Volume-based median diameter of crystalline polyester dispersion, colorant dispersion, etc.>
The volume-based median diameters of the crystalline polyester dispersion and the colorant dispersion were measured using a laser diffraction particle size distribution measuring device "LA-920" (manufactured by Horiba, Ltd.).
The resin particle dispersion was diluted with ethyl acetate so that the diffracted light intensity was within the measurement range, and the volume-based median diameter was measured at 25°C.

<Volume-Based Median Diameter of Resin Particle Dispersion>
The volume-based median diameter of the resin fine particles was measured using a dynamic light scattering particle size distribution measuring device "SZ-100" (manufactured by Horiba, Ltd.).
The resin fine particle dispersion was diluted 100-fold with ion-exchanged water, and the temperature was adjusted to 25° C., and then the diluted solution was filled into a disposable cell (transparent on all four sides). Next, the measurement mode was changed to a particle size measurement mode, and the volume-based median diameter was measured.

<Volume average particle diameter (D50) (μm), number average particle diameter (μm), particle size distribution (volume average particle diameter/number average particle diameter) of toner>
The measurement was carried out using a Coulter counter [product name: Multisizer III (manufactured by Beckman Coulter, Inc.)].
First, 0.1 to 5 mL of a surfactant (alkylbenzene sulfonate) was added as a dispersant to 100 to 150 mL of an electrolyte solution of ISOTON-II (manufactured by Beckman Coulter, Inc.). 2 to 20 mg of a measurement sample was then added, and the electrolyte solution in which the sample was suspended was subjected to a dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser. The toner volume and number were measured using a 50 μm aperture as an aperture using the measurement device, and the volume distribution and number distribution were calculated. From the distribution obtained, the volume average particle diameter (D50) (μm), number average particle diameter (μm), and particle size distribution (volume average particle diameter/number average particle diameter) of the toner were obtained.

<Production Example 1> [Synthesis of 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid]
In a 2 L reaction vessel equipped with a stirrer, 1000 parts of methanol, 150 parts of tartaric acid, and 104 parts of 2,2-dimethoxypropane were charged and reacted for 24 hours with stirring at 25° C. After the reaction, methanol was distilled off with an evaporator to obtain 190 parts of 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid.

<Production Example 2> [Synthesis of a mixture of 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol]
A 1 L reaction vessel equipped with a stirrer was charged with 290 parts of acetone, 182 parts of sorbitol, and 6 parts of 35 wt % hydrochloric acid, and reacted with stirring for 24 hours at 25° C. After the reaction, the mixture was neutralized to pH 7.5 with a 10 wt % aqueous sodium hydrogen carbonate solution, and the precipitated sodium chloride and molecular sieves were filtered off. The acetone was then distilled off with an evaporator, yielding 270 parts of a viscous liquid containing a mixture of 3,4:5,6-di-O-isopropylidene glucitol, 1,2:5,6-di-O-isopropylidene glucitol, and 1,2:3,4:5,6-tri-O-isopropylidene glucitol. The resulting viscous liquid was then distilled under reduced pressure to obtain 75 parts of a mixture of 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol as an effluent at 2 mmHg and 130 to 140° C.

<Production Example 3> [Synthesis of a mixture of 1,2:3,4-di-O-isopropylidenemannitol and 1,2:5,6-di-O-isopropylidenemannitol]
In a 1L reaction vessel equipped with a stirrer, 290 parts of acetone, 182 parts of mannitol, and 3 parts of 96 wt% sulfuric acid were charged and reacted at 40 ° C. for 2 hours while stirring. Then, 350 parts of molecular sieves 3A (pore size 3 Å) were added, and dehydration reaction was carried out at 40 ° C. for 12 hours while stirring. After the reaction, the mixture was neutralized to pH 7.5 with a 10 wt% aqueous ammonium hydrogen carbonate solution, and acetone was distilled off with an evaporator to obtain 301 parts of a viscous liquid containing 1,2:3,4-di-O-isopropylidenemannitol, 1,2:5,6-di-O-isopropylidenemannitol, and 1,2:3,4:5,6-tri-O-isopropylidenemannitol. Subsequently, 600 parts of water was added to the obtained viscous liquid, and the mixture was allowed to stand after mixing to separate into two layers. The upper layer of the two layers was collected and water was removed using an evaporator to obtain 76 parts of a mixture of 1,2:3,4-di-O-isopropylidenemannitol and 1,2:5,6-di-O-isopropylidenemannitol.

Example 1 Synthesis of amorphous polyester (L-1)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen inlet tube, 415 parts of propylene glycol, 605 parts of 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid obtained in Production Example 1, 71 parts of succinic acid and 2.5 parts of titanium dihydroxybis (triethanol aminate) as a condensation catalyst were added, and the temperature was raised to 200 ° C. under a reduced pressure of 0.5 to 2.5 kPa, while the water and propylene glycol produced were distilled off to react, and when the acid value became less than 2 mg KOH / g, 29 parts of trimellitic anhydride were added, and further, the reaction was carried out at 180 ° C. under normal pressure, and when the acid value became 18 mg KOH / g, the product was taken out to obtain amorphous polyester (L-1). The amount of propylene glycol distilled off was 120 parts.

Example 2 Synthesis of amorphous polyester (L-2)
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, 605 parts of a mixture of 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol, 367 parts of terephthalic acid, and 2.5 parts of titanium dihydroxybis(triethanolamine) as a condensation catalyst were placed, and the mixture was reacted while distilling off the generated water while heating to 220° C. under a reduced pressure of 0.5 to 2.5 kPa. When the acid value became less than 2 mgKOH/g, 29 parts of trimellitic anhydride was added, and the mixture was further reacted at 180° C. under normal pressure. When the acid value became 18 mgKOH/g, the mixture was taken out, and amorphous polyester (L-2) was obtained.

Example 3 Synthesis of amorphous polyester (L-3)
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, 605 parts of a mixture of 1,2:3,4-di-O-isopropylidenemannitol and 1,2:5,6-di-O-isopropylidenemannitol, 367 parts of terephthalic acid, and 2.5 parts of titanium dihydroxybis(triethanolaminate) as a condensation catalyst were placed, and the mixture was reacted while distilling off the generated water while heating to 220° C. under a reduced pressure of 0.5 to 2.5 kPa. When the acid value became less than 2 mgKOH/g, 29 parts of trimellitic anhydride was added, and the mixture was further reacted at 180° C. under normal pressure. When the acid value became 18 mgKOH/g, the mixture was taken out, and amorphous polyester (L-3) was obtained.

Example 4 Synthesis of amorphous polyester (L-4)
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, 574 parts of a mixture of 1,2:3,4-di-O-isopropylidenemannitol and 1,2:5,6-di-O-isopropylidenemannitol, 396 parts of 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid, and 2.5 parts of titanium dihydroxybis(triethanolaminate) as a condensation catalyst were placed, and the mixture was reacted while distilling off the generated water while heating to 220° C. under a reduced pressure of 0.5 to 2.5 kPa. When the acid value became less than 2 mgKOH/g, 30 parts of trimellitic anhydride was added, and the mixture was further reacted at 180° C. under normal pressure. When the acid value became 18 mgKOH/g, the mixture was taken out, and amorphous polyester (L-4) was obtained.

Example 5 Synthesis of amorphous polyester (L-5)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen inlet tube, 399 parts of recovered PET (polyethylene terephthalate), 573 parts of a mixture of 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol, and 2.5 parts of titanium dihydroxybis(triethanolamine) as a condensation catalyst were placed, depolymerized at 220°C under normal pressure for 3 hours, and then reacted while distilling off ethylene glycol at 220°C under a reduced pressure of 0.5 to 2.5 kPa, and when the acid value became less than 2 mgKOH/g, 27 parts of trimellitic anhydride were added, and further reacted at 180°C under normal pressure, and when the acid value became 18 mgKOH/g, the mixture was taken out to obtain amorphous polyester (L-5). The amount of ethylene glycol distilled off from the recovered PET was 118 parts.

Example 6 Synthesis of amorphous polyester (L-6)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen inlet tube, 758 parts of recovered PET (polyethylene terephthalate), 221 parts of a mixture of 3,4:5,6-di-O-isopropylidene glucitol and 1,2:5,6-di-O-isopropylidene glucitol, 548 parts of propylene glycol and 2.5 parts of titanium dihydroxybis(triethanolamine) as a condensation catalyst were added, and the mixture was depolymerized at 220°C under normal pressure for 3 hours, and then reacted while distilling off ethylene glycol and propylene glycol at 220°C under a reduced pressure of 0.5 to 2.5 kPa, and when the acid value became less than 2 mgKOH/g, 31 parts of trimellitic anhydride were added, and further reacted at 180°C under normal pressure, and when the acid value became 18 mgKOH/g, the mixture was taken out to obtain amorphous polyester (L-6). The amounts of ethylene glycol and propylene glycol distilled off from the recovered PET were 133 parts and 424 parts, respectively.

Comparative Example 1 Synthesis of Comparative Amorphous Polyester (LR-1)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen inlet tube, 476 parts of propylene glycol, 534 parts of terephthalic acid, 61 parts of succinic acid and 2.5 parts of titanium dihydroxybis(triethanolamine) as a condensation catalyst were added, and the mixture was reacted while distilling off the water and propylene glycol produced while heating to 230 ° C. under a reduced pressure of 0.5 to 2.5 kPa, and when the acid value became less than 2 mgKOH / g, 25 parts of trimellitic anhydride were added, and the mixture was further reacted at 180 ° C. under normal pressure, and when the acid value became 18 mgKOH / g, it was taken out to obtain amorphous polyester (LR-1). The amount of propylene glycol distilled off was 95 parts.

Comparative Example 2 Synthesis of Comparative Amorphous Polyester (LR-2)
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, 677 parts of bisphenol A·EO 2-mol adduct, 294 parts of terephthalic acid, and 2.5 parts of titanium dihydroxybis(triethanolamine) as a condensation catalyst were placed, and the mixture was reacted while distilling off the generated water while heating to 230°C under a reduced pressure of 0.5 to 2.5 kPa. When the acid value became less than 2 mgKOH/g, 29 parts of trimellitic anhydride were added, and the mixture was further reacted at 180°C under normal pressure. When the acid value became 18 mgKOH/g, the mixture was taken out, and an amorphous polyester (LR-2) was obtained.

The compositions and physical properties of the amorphous polyesters (L-1) to (L-6) obtained in Examples 1 to 6 and the comparative amorphous polyesters (LR-1) to (LR-2) obtained in Comparative Examples 1 and 2 are shown in Table 1.

<Production Example 4> [Synthesis of crystalline polyester (C-1)]
434 parts of 1,6-hexanediol, 686 parts of sebacic acid, and 1.5 parts of titanium diisopropoxy bistriethanolamine as a condensation catalyst were placed in a reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, a cooling tube, and a nitrogen inlet tube, and reacted for 8 hours under a nitrogen stream at 220°C while distilling off the water generated. Thereafter, the reaction was continued under a reduced pressure of 0.001 to 0.026 MPa while removing water, to obtain a crystalline polyester (C-1). The resin had an Mn of 4500, an Mw of 15000, a melting point (Tm) of 68°C, an acid value of 1 mgKOH/g, and a hydroxyl value of 21 mgKOH/g.

<Production Example 5> [Production of Crystalline Polyester Dispersion (CDO-1)]
In a reaction vessel equipped with a cooling tube, a stirrer, a heating/cooling device, and a thermometer, 10 parts of crystalline polyester (C-1) and 90 parts of ethyl acetate were added, heated to 78°C, stirred at the same temperature for 3 hours, and then cooled to 30°C over 1 hour to crystallize the crystalline polyester (C-1) into fine particles, which were then wet-pulverized using an Ultraviscomill (manufactured by Imex) to obtain a crystalline polyester dispersion (CDO-1). The volume-based median diameter of the crystalline polyester dispersion (CDO-1) measured using "LA-920" was 0.25 μm.

Production Example 6 Production of Aqueous Dispersion of Resin Fine Particles (OW-1)
In a reaction vessel equipped with a stirrer, a heating/cooling device, and a thermometer, 790 parts of water and 5 parts of sodium alkylarylsulfosuccinate (Eleminol JS-20, manufactured by Sanyo Chemical Industries) were charged, and the mixture was homogenized by stirring at 200 rpm. This was heated to raise the temperature in the system to 75 ° C., and then 5 parts of a 10 wt % aqueous ammonium persulfate solution was added, followed by dropping a monomer mixture consisting of 89.6 parts of styrene, 49.0 parts of butyl acrylate, and 61.4 parts of methacrylic acid over 2 hours. After dropping, the mixture was aged at 75 ° C. for 10 hours to obtain 1000 parts of a microparticle dispersion (OW-1) containing oil microparticles. The volume-based median diameter of the microparticles contained in the microparticle dispersion was 0.047 μm. A part of the microparticle dispersion was dried to isolate the resin. The resin fraction had an Mn of 30,900, an Mw of 321,000, a Tg of 60° C. and an acid value of 200 mg KOH/g.

<Production Example 7> [Production of modified wax (WD-1)]
In a pressure-resistant reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, and a dropping cylinder, 454 parts of xylene and 150 parts of low molecular weight polyethylene "Sanwax LEL-400" [softening point: 128 ° C., manufactured by Sanyo Chemical Industries, Ltd.] were charged, and after nitrogen replacement, the temperature was raised to 170 ° C. with stirring, and a mixed solution of 595 parts of styrene, 255 parts of methyl methacrylate, 34 parts of di-t-butyl peroxyhexahydroterephthalate, and 119 parts of xylene was dropped at the same temperature over 3 hours, and the mixture was maintained at the same temperature for 30 minutes. Next, xylene was distilled off under a reduced pressure of 0.039 MPa to obtain a modified wax. The Mn of the modified wax was 1,900, the Mw was 5,200, and the Tg was 56.9 ° C.

<Production Example 8> [Production of release agent dispersion (WO-1)]
Into a reaction vessel equipped with a cooling tube, a stirrer, a heating/cooling device, and a thermometer, 10 parts of paraffin wax "HNP-9" [melting point: 73°C, manufactured by Nippon Seiro Co., Ltd.], 5 parts of the modified wax (WD-1) obtained in Production Example 7, and 85 parts of ethyl acetate were added, and the mixture was heated to 78°C and stirred at the same temperature for 3 hours. The mixture was then cooled to 30°C over 1 hour to crystallize the release agent into fine particles, which were then wet-pulverized with an Ultraviscomill (manufactured by Imex) to obtain a release agent dispersion (WO-1). The volume-based median diameter of the release agent dispersion (WO-1) measured with an "LA-920" was 0.25 μm.

<Production Example 9> [Production of Colorant Dispersion (PO-1)]
20 parts of carbon black "MA100" [manufactured by Mitsubishi Chemical Corporation], 4 parts of colorant dispersant "Solsperse 28000" [manufactured by Avecia Corporation], and 56 parts of ethyl acetate were added to a reaction vessel equipped with a stirrer, a heating/cooling device, a cooling tube, and a thermometer, and the mixture was stirred to uniformly disperse, after which the pigment was finely dispersed using a beads mill to obtain a colorant dispersion liquid (PO-1). The volume-based median diameter of the colorant dispersion liquid (PO-1) measured with "LA-920" was 0.2 μm.

Example 7 Preparation of Toner (T-1)
A toner was obtained by the following method (dissolution suspension method) using the aqueous dispersion (OW-1) obtained in Production Example 6, the amorphous polyester (L-1) obtained in Example 1, the colorant dispersion (PO-1) obtained in Production Example 9, the release agent dispersion (WO-1) obtained in Production Example 8, and the crystalline polyester dispersion (CDO-1) obtained in Production Example 5.
In a beaker, 330 parts of ion-exchanged water, 30 parts of an aqueous dispersion of resin fine particles (OW-1), 2 parts of sodium carboxymethylcellulose, 52 parts of sodium dodecyl diphenyl ether disulfonate "Eleminol Mon-7" [manufactured by Sanyo Chemical Industries], and 28 parts of ethyl acetate were added, and an aqueous solution was obtained by uniformly mixing. Next, in another beaker, 90 parts of amorphous polyester (L-1), 32 parts of a colorant dispersion (PO-1), 40 parts of a release agent dispersion (WO-1), and 100 parts of a crystalline polyester dispersion (CDO-1) were mixed to prepare a resin dispersion in which the amorphous polyester was dissolved. The entire amount of this dispersion was added to the aqueous solution previously prepared and stirred for 2 minutes with a TK auto homomixer to obtain a mixed solution. Next, this mixed solution was transferred to a reactor equipped with a stirrer and a thermometer, and the ethyl acetate was distilled off at 50 ° C. until the concentration became 0.5 wt % or less, and a composite process was performed to obtain an aqueous resin dispersion of resin particles. The resin particles were then filtered and washed with water three times, filtered, and dried for 18 hours in a 40° C. air circulation dryer to obtain resin particles containing the polyester resin (L-1) for toner of the present invention with a volatile content of 0.5% by weight or less. Next, 100 parts of the resin particles and 1 part of hydrophobic silica "Aerosil R-972" [manufactured by Nippon Aerosil] were mixed in a sample mill to obtain the toner (T-1) of the present invention.

Example 8: Production of toner (T-2)
The same production method as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (L-2) obtained in Example 2, and a toner (T-2) containing the polyester resin for toner (L-2) of the present invention was obtained.

Example 9: Production of toner (T-3)
The same production method as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (L-3) obtained in Example 3, and a toner (T-3) containing the polyester resin for toner (L-3) of the present invention was obtained.

Example 10: Production of toner (T-4)
The same production method as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (L-4) obtained in Example 4, and a toner (T-4) containing the polyester resin for toner (L-4) of the present invention was obtained.

Example 11: Production of toner (T-5)
The same production method as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (L-5) obtained in Example 5, and a toner (T-5) containing the polyester resin for toner (L-5) of the present invention was obtained.

Example 12: Production of toner (T-6)
The same production method as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (L-6) obtained in Example 6, and a toner (T-6) containing the polyester resin for toner (L-6) of the present invention was obtained.

Comparative Example 3: Production of Toner (TR-1)
The same production as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (LR-1) obtained in Comparative Example 1, and a toner (TR-1) containing a polyester resin for toner (LR-1) was obtained.

Comparative Example 4: Production of Toner (TR-2)
The same production as in Example 7 was carried out except that the amorphous polyester was changed to the amorphous polyester (LR-2) obtained in Comparative Example 2, and a toner (TR-2) containing the toner polyester resin (LR-2) was obtained.

The low-temperature fixing property and heat-resistant storage property of the toners (T-1) to (T-6) and (TR-1) to (TR-2) of the examples and comparative examples were evaluated by the following methods. The physical properties and evaluation results of each toner are shown in Table 2.

<Low temperature fixability>
The toner is uniformly placed on the paper surface to a ^density of 0.8 mg/cm2. The method for placing the powder on the paper surface at this time is to use a printer without a thermal fixing unit. Other methods may be used as long as the powder can be uniformly placed at the above weight density.
The paper was passed through a pressure roller at a fixing speed (heat roller peripheral speed) of 213 mm/sec and a fixing pressure (pressure roller pressure) of 10 kg/cm ² , and the temperature at which cold offset occurred (MFT) was measured.
The lower the temperature at which cold offset occurs, the better the low-temperature fixing property.
In this evaluation condition for low-temperature fixability, a temperature of 125° C. or lower is considered to be preferable.
◎: 105℃ or less ○: 106～115℃
△: 116-125℃
×: 126°C or higher

<Heat and humidity resistance storage>
The toners (T-1) to (T-6) and (TR-1) to (TR-2) were allowed to stand for 20 hours in an atmosphere of 40° C. and 80% relative humidity, and the humidity and heat resistance storage stability was evaluated according to the degree of blocking according to the following criteria.
[Evaluation Criteria]
◯: No blocking occurs.
△: Blocking occurs, but it disperses easily when force is applied.
×: Blocking occurs and the particles do not disperse even when force is applied.

The toners (T-1) to (T-6) containing the polyester resins (L-1) to (L-6) of the present invention exhibited excellent performance in both low-temperature fixing property and heat and humidity resistant storage property.
On the other hand, the toners (TR-1) and (TR-2) using the polyester resins (LR-1) and (LR-2) were poor in low temperature fixability and humidity and heat resistance storage stability.

The polyester resin for toner of the present invention can achieve both low-temperature fixing property and moist heat resistance storage stability at high levels, and is extremely useful as a resin for use in toner for developing electrostatic images used in electrophotography, electrostatic recording, electrostatic printing, etc.

Claims (6)

A polyester resin for a toner, characterized by having a 1,3-dioxolane structure , the polyester resin being a resin obtained by using, as raw material monomers, a carboxylic acid component containing at least a carboxylic acid compound having a 1,3-dioxolane structure and/or an alcohol component containing an alcohol having a 1,3-dioxolane structure, and subjecting the carboxylic acid component and the alcohol component to condensation polymerization, the total amount of the carboxylic acid compound having a 1,3-dioxolane structure and the alcohol having a 1,3-dioxolane structure being 10 to 100 mol % of the total amount of the carboxylic acid component and the alcohol component . The polyester resin for toner according to claim 1, which has a glass transition temperature of 40 to 120°C. The polyester resin for toner according to claim 1, wherein the 1,3-dioxolane structure is 2,2-dimethyl-1,3-dioxolane. 2. The polyester resin for toner according to claim 1 , wherein the carboxylic acid compound having a 1,3-dioxolane structure is 2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylic acid. 2. The polyester resin for toner according to claim 1, wherein the alcohol having a 1,3-dioxolane structure is at least one selected from the group consisting of 3,4:5,6-di-O-isopropylidene glucitol, 1,2:5,6-di-O-isopropylidene glucitol, 1,2:3,4-di-O-isopropylidene mannitol, and 1,2:5,6 -di-O-isopropylidene mannitol. A toner comprising the polyester resin for toners according to any one of claims 1 to 5 .