JP6708440B2 - Toner manufacturing method - Google Patents

Description

The present invention relates to a method for producing a toner for visualizing an electrostatic latent image in an image forming method such as an electrophotographic method, an electrostatic recording method, a magnetic recording method and a toner jet method.

Along with the demand for energy saving of image forming apparatuses such as multifunction peripherals and printers, it is required to improve the low temperature fixing property of toner. As a method for improving the low-temperature fixability of the toner, there is a method of improving the low-tone fixability by setting a lower softening point of the toner during fixing using a crystalline resin. This utilizes the sharp melting property of the crystalline resin to set the softening temperature of the toner lower.

However, the crystalline resins do not necessarily all have a crystalline structure with perfect regularity. When a crystalline resin is used as the toner material, it becomes compatible with the amorphous binder resin and the crystallinity is likely to decrease. The crystalline resin compatible with the binder resin lowers the softening point of the binder resin even at room temperature, so that the heat-resistant storage stability of the resin easily deteriorates. Further, the low-crystalline component generated by the compatibility with the binder resin may increase the crystallinity gradually when left standing for a long time, which may cause a change in toner characteristics with time.

In order to solve these problems, a technique for increasing the crystallinity of the crystalline resin contained in the toner is known.

Patent Document 1 discloses a method for producing a toner including a step of storing the toner at a temperature of 45° C. to 65° C. when producing the toner.

Patent Document 2 discloses a manufacturing method in which a toner containing a crystalline resin is exposed to carbon dioxide in a supercritical or subcritical state.

JP, 2006-065015, A JP, 2010-168530, A

However, as a result of the study by the present inventors, the crystallization of a part of the compatible crystalline resin was promoted by the process described in Patent Document 1, but it took a long time for the crystallization. Therefore, it was found that the effect is not always sufficient.

On the other hand, according to the method described in Patent Document 2, it was found that the crystalline resin contained in the toner was crystallized in a short time and a toner excellent in heat resistant storage stability was obtained. However, when performing treatment with carbon dioxide in the supercritical or subcritical state, it is necessary that the binder resin is incompatible with carbon dioxide in the supercritical or subcritical state. Examples of the binder resin satisfying the above conditions include a method of using a binder resin having a high acid value to reduce the solubility in carbon dioxide in a supercritical or subcritical state.

However, when a resin having a high acid value is used as a binder resin, environmental fluctuations due to polar functional groups that increase the acid value become large, and good charging characteristics cannot be obtained, and image adverse effects are likely to occur. It turns out that there are new challenges. Therefore, there is a demand for a toner that has excellent low-temperature fixability and heat-resistant storage stability, and that is capable of forming a stable toner image in any use environment.

An object of the present invention is to provide a toner manufacturing method capable of manufacturing a toner having excellent low-temperature fixability and heat-resistant storage stability, and excellent chargeability.

The present invention is a method for producing a toner having toner particles having a binder resin and a crystalline resin,
The manufacturing method includes the following carbon dioxide exposure treatment step (i) or (ii),
(I) Carbon dioxide having a temperature of 10° C. or higher and 60° C. or lower and a pressure of 1.0 MPa or higher and 3.5 MPa or lower is exposed to the toner particles having a binder resin and a crystalline resin before exposure to carbon dioxide for 5 minutes or longer and 180 minutes or shorter. To obtain toner;
(Ii) Carbon dioxide having a temperature of 10° C. or more and 60° C. or less and a pressure of 1.0 MPa or more and 3.5 MPa or less is added to the toner before the carbon dioxide exposure treatment having the toner particles having the binder resin and the crystalline resin and the external additive. A step of obtaining toner by exposing for 5 minutes or more and 180 minutes or less ;
Acid value before Kiyuigi resin, not more than 15.0 mg KOH / g,
The absolute value (ΔSP value) of the difference between the SP value of the binder resin and the SP value of the crystalline resin is 0.03 or more and 0.20 or less,
The present invention relates to a method for producing a toner, wherein glass transition temperatures (Tg1, Tg2) of the toner in differential scanning calorimetry (DSC) satisfy the following formulas (1) and (2).

Tg1≧50°C (1)
0.60≦Tg2/Tg1≦0.85 (2)
(In formulas (1) and (2),
Tg1 represents the glass transition temperature at the first temperature rise in the DSC measurement of the toner.
Tg2 represents the glass transition temperature at the second temperature rise in the DSC measurement of the toner. )

According to the present invention, it is possible to provide a toner manufacturing method capable of manufacturing a toner having excellent low-temperature fixability and heat-resistant storage stability, and excellent chargeability.

Schematic diagram showing an example of a pressure holding device

The embodiments of the present invention will be specifically described below.

The method for producing a toner of the present invention (hereinafter, also simply referred to as the production method of the present invention) is a method for producing a toner having toner particles having a binder resin and a crystalline resin, and includes the following (i) or (ii) Exposure process.
(I) A step of exposing the untreated toner particles having a binder resin and a crystalline resin to carbon dioxide to obtain toner particles.
(Ii) A step of obtaining a toner by exposing the untreated toner having the toner particles having the binder resin and the crystalline resin and the external additive to carbon dioxide.

In the present invention, the carbon dioxide temperature in the exposure treatment step is 10° C. or higher and 60° C. or lower, and the carbon dioxide pressure is 1.0 MPa or higher and 3.5 MPa or lower.

Further, the acid value of the binder resin is 15.0 mgKOH/g or less, and the glass transition temperatures (Tg1, Tg2) of the toner in differential scanning calorimetry (DSC) satisfy the following formulas (1) and (2). Is characterized by.

Tg1≧50°C (1)
0.60≦Tg2/Tg1≦0.85 (2)
(In the formulas (1) and (2), Tg1 represents the glass transition temperature at the first temperature increase in the toner DSC measurement. Tg2 represents the glass transition temperature at the second temperature increase in the toner DSC measurement. .)

By exposing the toner particles before treatment or the toner before treatment to carbon dioxide under specific conditions, it becomes possible to stably produce a toner excellent in low-temperature fixing property and heat-resistant storage stability and excellent in charging property. I found that.

Specifically, the untreated toner particles or the untreated toner are exposed to carbon dioxide having a temperature of 10° C. to 60° C. and a pressure of 1.0 MPa to 3.5 MPa (hereinafter, also referred to as exposure treatment). This solves the above problem. Specifically, it is considered that the crystallization of the crystalline resin was enhanced by the above-mentioned carbon dioxide exposure treatment. The effect of enhancing the crystallization of this crystalline resin is also called an annealing effect.

In the exposure treatment with carbon dioxide, the solubility of carbon dioxide changes depending on the exposure temperature and pressure. Therefore, when the temperature of carbon dioxide is lower than 10° C. or when the pressure is lower than 1.0 MPa, the solubility of carbon dioxide is too low and the swelling of the binder resin is unlikely to occur, resulting in crystallization of the crystalline resin. It becomes difficult to proceed. On the contrary, when the temperature of carbon dioxide is higher than 60° C. or when the pressure is higher than 3.5 MPa, the solubility of carbon dioxide becomes too high and the toner particles are fused and coalesced to generate coarse particles. I will end up.

In the present invention, the acid value of the binder resin is 15.0 mgKOH/g or less. When the acid value of the binder resin is 15.0 mgKOH/g or less, charging failure due to polar functional groups is less likely to occur, and stable charging properties can be obtained even in environments such as low temperature and low humidity environments and high temperature and high humidity environments. A good image can be obtained. Further, when the acid value of the binder resin is larger than 15.0 mgKOH/g, the carbon dioxide does not sufficiently penetrate into the binder resin in the exposure treatment of the present invention because the solubility of the binder resin in carbon dioxide is low. The effect of promoting crystallization cannot be obtained.

A carbon dioxide having a temperature of 10° C. or higher and 60° C. or lower and a pressure of 1.0 MPa or higher and 3.5 MPa or lower is exposed to a toner containing a binder resin having the above-mentioned specific acid value, and thus a low amount compatible with the binder resin is obtained. The crystallization of the crystal component can be promoted in a short time. It is considered that this makes it possible to obtain a toner having excellent heat-resistant storage stability and excellent chargeability.

Further, when the glass transition temperature at the first temperature rise in differential scanning calorimetry (DSC) of the toner is Tg1, and the glass transition temperature at the second temperature rise is Tg2, Tg1 and Tg2 are expressed by the following formula (1). And it is necessary to satisfy (2).

Tg1≧50°C (1)
0.60≦Tg2/Tg1≦0.85 (2)

By satisfying the above formulas (1) and (2), it is possible to achieve both heat-resistant storage stability before fixing and low-temperature fixability due to plasticity during fixing. When Tg1 is less than 50° C., heat-resistant storage stability before fixing tends to be poor. Further, when Tg2/Tg1 is larger than 0.85, when trying to obtain a sufficient fixing property, the blocking property is lowered, and it becomes difficult to achieve both the fixing property and the blocking property. When Tg2/Tg1 is less than 0.60, the compatibility of the crystalline resin with the binder resin is too high. Therefore, it is difficult to increase the crystallinity of the crystalline resin even by using the toner production method of the present invention. This is a difficult area.

In the present invention, the exposure time of carbon dioxide is preferably 5 minutes or more and 180 minutes or less. If it is 5 minutes or more, crystallization of the crystalline resin can be sufficiently promoted. From the viewpoint of promoting crystallization of the crystalline resin, the upper limit time is not particularly limited as long as it is 5 minutes or more, but it is preferably 180 minutes or less from the viewpoint of productivity. It is more preferably 120 minutes or less, still more preferably 60 minutes or less.

Further, it is preferable that the toner production method of the present invention satisfies the following formula (4).

Tg1-Tg3≧2° C. (4)
(In Formula (4), Tg3 is the glass transition temperature at the first temperature rise in the differential scanning calorimetry (DSC) of the toner particles before the treatment in (i) or the toner particles in (ii)). Show.)

When Tg1 to Tg3 is 2° C. or higher, it means that the crystalline resin compatible with the binder resin is sufficiently phase-separated, and the heat resistance is further improved.

Known materials can be used for the crystalline resin, and examples thereof include crystalline polyester, crystalline vinyl, and crystalline urethane. Among these, a crystalline polyester is preferable, and a crystalline polyester having a unit represented by the following formula (3) is more preferable.

(In the formula (3), m and n each independently represent an integer of 4 or more and 16 or less (preferably 6 or more and 12 or less).)

If the crystalline polyester has a unit represented by the above formula (3), the effect of the present invention can be easily obtained. The crystalline polyester may be a modified polymer such as block-modified or graft-modified. As the modified polymer, a polystyrene-modified crystalline polyester is particularly preferable.

The crystalline polyester represented by the above formula (3) is, for example, a condensate of a dicarboxylic acid represented by the following formula (A), its alkyl ester compound or acid anhydride, and a diol represented by the following formula (B). is there.
HOOC- _{(CH 2)} m -COOH formula (A)
(In the formula (A), m represents an integer of 4 or more and 16 or less (preferably 6 or more and 12 or less))
HO- _{(CH 2)} n -OH Formula (B)
(In the formula (B), n represents an integer of 4 or more and 16 or less (preferably 6 or more and 12 or less))

As the dicarboxylic acid, a compound in which a carboxyl group is alkyl esterified (preferably having 1 to 4 carbon atoms), an acid anhydride compound, or the like may be used as long as it forms the same partial skeleton in the polyester portion.

As the dicarboxylic acid represented by the above formula (A), suberic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid and the like are preferable.

Examples of the diol represented by the above formula (B) include 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,9-nonanediol, 1,10-decanediol and 1,12. -Dodecanediol and the like are preferred.

The content of the crystalline resin is preferably 2.0 parts by mass or more and 25.0 parts by mass or less, and 3.0 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin. Is more preferable. When the amount is 2.0 parts by mass (more preferably 3.0 parts by mass) or more, the low-temperature fixability is further improved due to the plasticizing effect during melting. When the amount is 25.0 parts by mass (more preferably 20.0 parts by mass) or less, the charging property is less likely to decrease and fogging is less likely to occur. Moreover, since the stress resistance does not easily decrease, the durability is excellent. Further, since the solubility in carbon dioxide is also maintained, the heat resistance can be easily improved by the crystallization of the crystalline resin.

As the binder resin, any type of resin can be used as long as it has an acid value of 15.0 mgKOH/g or less. A polyester resin or a styrene acrylic resin is preferable.

As the polyester-based resin, a resin obtained by condensation-polymerizing a carboxylic acid component monomer and an alcohol component monomer listed below can be used. Carboxylic acid component monomers include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and shono acid. Examples include carboxylic acid, cyclohexanedicarboxylic acid, and trimellitic acid.

As the alcohol component monomer, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-bis(hydroxymethyl) ) Alkylene glycols and polyalkylene glycols of cyclohexane, bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

As the styrene acrylic resin, resins obtained by radically polymerizing the following polymerizable monomers can be used.

As the polymerizable monomer, styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, and p -Styrene derivatives such as phenylstyrene;
Methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate , N-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and acrylic polymerizable monomers such as 2-benzoyloxyethyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate , N-nonyl methacrylate, diethyl phosphate ethyl methacrylate, and methacrylic polymerizable monomers such as dibutyl phosphate ethyl methacrylate.

Examples of the polyfunctional polymerizable monomer include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol. Diacrylate, polypropylene glycol diacrylate, 2,2'-bis(4-(acryloxydiethoxy)phenyl)propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene Glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4-(methacryloxydiethoxy)phenyl)propane, 2,2′-bis(4-(methacryloxypolyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, And divinyl ether.

It is preferable to use two or more kinds of polymerizable monomers in combination, from the viewpoint of developing characteristics and durability of the toner.

The weight average molecular weight (Mw) of the binder resin is preferably 10,000 or more and 50,000 or less. Within this range, the balance between developability and fixability becomes better.

The absolute value (ΔSP value) of the difference in SP value (solvability parameter) between the binder resin and the crystalline resin is preferably 0.03 or more and 0.20 or less. Within this range, the phase separation of the binder resin and the crystalline resin in the toner and the compatibility of the binder resin and the crystalline resin at the time of melting can be easily controlled, and both low temperature fixing and heat resistance can be easily achieved. Moreover, the SP value of the crystalline resin is preferably 9.50 or more and 9.85 or less, and the SP value of the binder resin is preferably 9.50 or more and 9.85 or less.

The manufacturing method for manufacturing the toner according to the present invention may be any manufacturing method, but for toner in an aqueous medium such as suspension polymerization method, emulsion polymerization method and suspension granulation method. It is preferably obtained by a method for producing a toner in which the composition is granulated.

Hereinafter, the method for producing a toner will be described using the most preferable suspension polymerization method among the methods for producing a toner used in the present invention.

A polymerizable monomer capable of forming a binder resin, a crystalline resin, and, if necessary, other additives such as a colorant and a wax are uniformly dissolved or dispersed in a disperser, and a polymerization initiator is added thereto. Are dissolved to prepare a polymerizable monomer composition. Next, the polymerizable monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer to form droplets of the polymerized monomer composition. Polymerization produces toner particles (toner particles before exposure to carbon dioxide). Examples of the disperser include a homogenizer, a ball mill, a colloid mill, and an ultrasonic disperser.

The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. A polymerization initiator dissolved in a polymerizable monomer or a solvent may be added immediately after granulation and before the polymerization reaction is started.

In the case of a polymerization method using an aqueous medium such as a suspension polymerization method, it is preferable to add a polar resin to the above mixed solution. By adding the polar resin, the inclusion of the crystalline resin or wax can be promoted.

When the polar resin is present in the colorant dispersion liquid suspended in the aqueous medium, the polar resin easily migrates to the vicinity of the interface between the aqueous medium and the colorant dispersion liquid due to the difference in affinity for water. The polar resin is unevenly distributed on the surface. As a result, the toner particles have a core-shell structure.

If a polar resin having a high melting temperature is selected as the shell-constituting polar resin, blocking may occur during storage of the toner even if the binder resin is designed to be melted at a lower temperature for the purpose of low-temperature fixing. Can be suppressed.

The polar resin is preferably a polyester resin or a carboxyl-containing styrene resin. By using a polyester resin or a carboxyl-containing styrene resin as the polar resin, when the resin is unevenly distributed on the surface of the toner particles to form a shell, the lubricity of the resin itself can be expected.

As the polyester-based resin, a resin obtained by condensation-polymerizing a carboxylic acid component monomer and an alcohol component monomer listed below can be used. Acid component monomers include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, camphor Acids, cyclohexanedicarboxylic acid, and trimellitic acid.

As the alcohol component monomer, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-bis(hydroxymethyl) ) Alkylene glycols and polyalkylene glycols of cyclohexane, bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

The carboxyl group-containing styrene-based resin is preferably a styrene-based acrylic acid copolymer, a styrene-based methacrylic acid copolymer, a styrene-based maleic acid copolymer, or the like. Particularly, a styrene-acrylic acid ester-acrylic acid type copolymer is preferable because the charge amount can be easily controlled. Further, the carboxyl group-containing styrene-based resin more preferably contains a unit derived from a monomer having a primary or secondary hydroxyl group. Specific polymer compositions include styrene-2-hydroxyethyl methacrylate-methacrylic acid-methyl methacrylate copolymer, styrene-n-butyl acrylate-2-hydroxyethyl methacrylate-methacrylic acid-methyl methacrylate copolymer. , Styrene-α-methylstyrene-2-hydroxyethyl methacrylate-methacrylic acid-methyl methacrylate copolymer and the like. A resin containing a unit derived from a monomer having a primary or secondary hydroxyl group has a large polarity, and the long-term storage stability becomes better.

The content of the polar resin is 1.0 part by mass or more and 20.0 parts by mass with respect to 100.0 parts by mass of the binder resin (styrene acrylic resin (or a polymerizable monomer that produces styrene acrylic resin) and crystalline resin). It is preferably less than or equal to parts by mass. More preferably, it is 2.0 parts by mass or more and 10.0 parts by mass or less.

In the present invention, a known wax may be used as the wax. Specifically, paraffin wax, microcrystalline wax, petroleum wax of petrolactam and its derivatives, montan wax and its derivatives, hydrocarbon wax and its derivatives by the Fischer-Tropsch method, polyolefin wax represented by polyethylene and its derivatives, Examples thereof include natural waxes of carnauba wax and candelilla wax and their derivatives, and the derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. In addition, alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid or compounds thereof; acid amides, esters, ketones, hydrogenated castor oil and its derivatives, vegetable wax, animal wax. These can be used alone or in combination.

Among these, when a polyolefin, a hydrocarbon wax produced by the Fischer-Tropsch method, or a petroleum wax is used, the effect of improving the developability and transferability is further enhanced. An antioxidant may be added to these wax components within a range that does not affect the charging property of the toner. Further, these wax components are preferably used in an amount of 1.0 part by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

The melting point of the wax used in the present invention is preferably in the range of 30°C to 120°C, more preferably 60°C to 100°C. By using the wax having the above melting point, not only the good fixing property of the obtained toner but also the releasing effect of the wax is efficiently exhibited, and a sufficient fixing area is secured.

In the present invention, the following organic pigments, organic dyes, and inorganic pigments may be used as the colorant.

Examples of cyan colorants include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specifically, the following are mentioned. C. I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

Examples of magenta colorants include the following. Condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, the following are mentioned. C. I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254, C.I. I. Pigment Violet 19.

Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, the following are mentioned. C. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185, 191, and 194.

Examples of the black colorant include carbon black and those toned in black using the yellow colorant, the magenta colorant, and the cyan colorant.

These colorants can be used alone or in combination, and can be used in the state of solid solution. The colorant used in the present invention is selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in toner particles.

The colorant is preferably used in an amount of 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

When toner particles are obtained using the suspension polymerization method, it is preferable to use a colorant that has been subjected to a hydrophobic treatment with a substance that does not inhibit polymerization, in consideration of the polymerization inhibitory property and the water phase transfer property of the colorant. .. As a preferred method of hydrophobizing a dye, a method of polymerizing a polymerizable monomer in the presence of these dyes in advance to obtain a colored polymer can be mentioned. The obtained colored polymer is a polymerizable monomer. There is a method of adding to the composition.

Further, carbon black may be treated with a substance (polyorganosiloxane) that reacts with the surface functional groups of carbon black, in addition to the same hydrophobic treatment as the above dye.

Moreover, you may use a charge control agent as needed. As the charge control agent, known charge control agents can be used, and in particular, a charge control agent that has a high triboelectrification speed and can stably maintain a constant triboelectrification amount is preferable. Further, when the toner particles are produced by the suspension polymerization method, a charge control agent having a low polymerization inhibitory property and substantially no solubilized product in an aqueous medium is particularly preferable.

Charge control agents include those that control the toner to be negatively charged and those that control it to be positively charged. The following are examples of controlling the toner to be negatively charged. Monoazo metal compound, acetylacetone metal compound, aromatic oxycarboxylic acid, aromatic dicarboxylic acid, oxycarboxylic acid and dicarboxylic acid type metal compound, aromatic oxycarboxylic acid, aromatic mono- and polycarboxylic acid and metal salt thereof, Examples thereof include anhydrides, esters, phenol derivatives such as bisphenol, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, and charge control resins.

On the other hand, examples of the charge control agent that controls the toner to be positively charged include the following. Guanidine compounds; imidazole compounds; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and onium salts such as phosphonium salts which are analogs thereof. And these lake pigments; triphenylmethane dyes and these lake pigments (as the laking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, and Ferrocyanide); metal salt of higher fatty acid; charge control resin.

You may add these charge control agents individually or in combination of 2 or more types.

Among these charge control agents, metal-containing salicylic acid compounds are preferable, and those whose metal is aluminum or zirconium are particularly preferable.

The addition amount of the charge control agent is preferably 0.01 parts by mass or more and 20.0 parts by mass or less, more preferably 0.5 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the binder resin. Is.

In addition, as the charge control resin, it is preferable to use a polymer or copolymer having a sulfonic acid group, a sulfonate group, or a sulfonate ester group. As the polymer having a sulfonic acid group, a sulfonic acid group or a sulfonic acid ester group, it is particularly preferable to contain a sulfonic acid group-containing acrylamide monomer or a sulfonic acid group-containing methacrylamide monomer in a copolymerization ratio of 2% by mass or more. .. More preferably, the content is 5% by mass or more. The charge control resin has a glass transition temperature (Tg) of 35° C. or more and 90° C. or less, a peak molecular weight (Mp) of 10,000 or more and 30,000 or less, and a weight average molecular weight (Mn) of 25,000 or more and 50,000 or less. Some are preferred. When this is used, preferable triboelectrification characteristics can be imparted without affecting the thermal characteristics required for the toner. Furthermore, since the charge control resin contains a sulfonic acid group, the dispersibility of the charge control resin itself in the dispersion liquid of the colorant, and the dispersibility of the colorant are improved, and the coloring power, transparency, and, The triboelectric charging property can be further improved.

A polymerization initiator may be used to polymerize the polymerizable monomer. Examples of the polymerization initiator that can be used in the present invention include organic peroxide type initiators and azo type polymerization initiators. Examples of the organic peroxide-based initiator include the following. Benzoyl peroxide, lauroyl peroxide, di-α-cumyl peroxide, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, bis(4-t-butylcyclohexyl)peroxydicarbonate, 1, 1-bis(t-butylperoxy)cyclododecane, t-butylperoxymaleic acid, bis(t-butylperoxy)isophthalate, methylethylketone peroxide, tert-butylperoxy-2-ethylhexanoate, diisopropyl Peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and tert-butyl-peroxypivalate.

As the azo polymerization initiator, 2,2′-azobis-(2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis(cyclohexane-1-carbonitrile) ), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobismethylbutyronitrile.

Further, as the polymerization initiator, a redox type initiator in which an oxidizing substance and a reducing substance are combined can be used. Examples of the oxidizing substances include hydrogen peroxide, inorganic peroxides of persulfates (sodium salt, potassium salt, and ammonium salt), and oxidizing metal salts of tetravalent cerium salt. Examples of the reducing substance include reducing metal salts (divalent iron salt, monovalent copper salt, and trivalent chromium salt), ammonia, lower amines (methylamine and ethylamine, such as C1-6). Amine), amino compounds such as hydroxylamine, sodium thiosulfate, sodium hydrosulfite, sodium bisulfite, sodium sulfite, and reducing sulfur compounds of sodium formaldehyde sulfoxylate, lower alcohols (having 1 to 6 carbon atoms). ), ascorbic acid or a salt thereof, and a lower aldehyde (having 1 to 6 carbon atoms).

The polymerization initiator is selected with reference to the 10-hour half-life temperature, and is used alone or in combination of two or more. The amount of the polymerization initiator added varies depending on the intended degree of polymerization, but it is preferable to add 0.5 parts by mass or more and 20.0 parts by mass or less to 100 parts by mass of the polymerizable monomer.

Further, a known chain transfer agent for controlling the degree of polymerization and a polymerization inhibitor may be further added and used.

Various crosslinking agents can also be used when polymerizing the polymerizable monomer. As the cross-linking agent, divinylbenzene, 4,4'-divinylbiphenyl, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, glycidyl acrylate, glycidyl methacrylate, trimethylolpropane triacrylate, and trimethylol Mention may be made of polyfunctional compounds such as propane trimethacrylate.

As the dispersion stabilizer used when preparing the aqueous medium, known inorganic compound dispersion stabilizers and organic compound dispersion stabilizers can be used. Examples of dispersion stabilizers for inorganic compounds include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate. , Barium sulfate, bentonite, silica, and alumina. On the other hand, examples of the dispersion stabilizer for organic compounds include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, and starch. The amount of these dispersion stabilizers used is preferably 0.2 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer.

When using a dispersion stabilizer of an inorganic compound among these dispersion stabilizers, a commercially available product may be used as it is, but in order to obtain a dispersion stabilizer having a finer particle diameter, the inorganic compound is formed in an aqueous medium. You may let me. For example, tricalcium phosphate can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high stirring.

An external additive may be externally added to the toner particles (toner particles before or after exposure treatment with carbon dioxide) in order to impart various properties to the toner. Examples of the external additive for improving the fluidity of the toner include silica fine particles, titanium oxide fine particles, and inorganic fine particles such as double oxide fine particles thereof. Among the inorganic fine particles, silica fine particles and titanium oxide fine particles are preferable. For example, the toner of the present invention can be obtained by externally adding inorganic fine particles to the toner particles and adhering them to the surface of the toner particles. As a method for externally adding the inorganic fine particles, a known method may be adopted. For example, a method of performing a mixing treatment using a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) can be mentioned.

Examples of the silica fine particles include dry silica or fumed silica produced by vapor phase oxidation of a silicon halide, and wet silica produced from water glass. As the inorganic fine particles, dry silica having less silanol groups on the surface and inside the silica fine particles and having less Na ₂ O and SO ₃ ²⁻ is preferable. Further, the dry silica may be composite fine particles of silica and another metal oxide by using a metal halogen compound such as aluminum chloride and titanium chloride together with a silicon halogen compound in the manufacturing process.

Since the surface of the inorganic fine particles is subjected to a hydrophobic treatment with a treating agent, the triboelectric charge amount of the toner can be adjusted, the environmental stability can be improved, and the fluidity under high temperature and high humidity can be improved. It is preferable to use inorganic fine particles that have been subjected to hydrophobic treatment. When the inorganic fine particles externally added to the toner absorb moisture, the triboelectric charge amount and the fluidity of the toner are reduced, and the developability and transferability are likely to be reduced.

As a treatment agent for hydrophobizing the inorganic fine particles, unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, and , And organic titanium compounds. Among them, silicone oil is preferable. These treating agents may be used alone or in combination.

The total addition amount of the inorganic fine particles is preferably 1.0 part by mass or more and 5.0 parts by mass or less, more preferably 1.0 part by mass or more and 2.5 parts by mass or less with respect to 100 parts by mass of the toner particles. is there. The external additive preferably has a particle size of 1/10 or less of the average particle size of the toner particles from the viewpoint of durability when added to the toner particles.

The exposure process using carbon dioxide may be performed either on the toner particles before the external addition of the inorganic fine particles or on the toner after the external addition of the inorganic fine particles. Specifically, in the exposure treatment step (i), carbon dioxide is exposed to the toner particles before treatment to obtain toner particles, and an external additive is added to the toner particles to obtain a toner. On the other hand, in the exposure treatment step (ii), an external additive is externally added to the toner particles to obtain a toner before treatment, and carbon dioxide is exposed to the toner before treatment to obtain a toner. The pressure holding device used for the exposure treatment with carbon dioxide is not particularly limited as long as it can be adjusted to a predetermined pressure and temperature, but description will be given based on an example of the pressure holding device shown in FIG.

In FIG. 1, a filter is provided in the pressure holding tank Ta1 so that the toner after the exposure process of carbon dioxide does not flow out of the tank Ta1 together with carbon dioxide when the medium is discharged to the outside through the pressure control valve V2. Is equipped with. Further, it has a stirring device for stirring for mixing.

In the carbon dioxide exposure process, first, the unprocessed toner particles or the unprocessed toner is put into a tank Ta1 whose temperature is adjusted to T1 (° C.) and stirred. Next, the valve V1 is opened, and the compressed carbon dioxide is introduced into the Ta1 from the container B1 in which the carbon dioxide is stored by using the compression pump P1, and the pressure in the Ta1 is increased to a predetermined pressure. When the predetermined pressure is reached, the pump is stopped, the valve V1 is closed, and the pressure is maintained. When a predetermined holding time has elapsed, the valve V2 is opened, carbon dioxide is discharged to the outside of Ta1, and the pressure in the tank Ta1 is reduced to atmospheric pressure. By passing through these steps, toner particles or toner that has been exposed to carbon dioxide is obtained.

Hereinafter, methods for measuring various physical properties according to the present invention will be described.

<SP value calculation method>
The SP value in the present invention was obtained using the Fedors equation (3). The values of Δei and Δvi are written in “Basic Science of Coating”, pp. 54-57, 1986 (Maki Shoten), Tables 3-9, Evaporation Energy and Molar Volume of Atoms and Atomic Groups (25° C.). Was referred to.
δi=[Ev/V] ^1/2 =[Δei/Δvi] ^1/2 Formula (3)
Ev: Evaporation energy V: Molar volume Δei: Evaporation energy of atom or atomic group of i component Δvi: Molar volume of atom or atomic group of i component For example, hexanediol is atomic group (—OH)×2+(—CH ₂ )×6, and the calculated SP value is calculated by the following formula.
δi=[Δei/Δvi] ^1/2 =[{(5220)×2+(1180)×6}/{(13)×2+(16.1)×6}] ^1/2
The SP value (δi) is 11.95.

<Measurement method of molecular weight of binder resin>
The weight average molecular weight (Mw) of the binder resin is measured by gel permeation chromatography (GPC) as follows.

First, the binder resin is dissolved in tetrahydrofuran (THF) at room temperature. Then, the obtained solution is filtered through a solvent-resistant membrane filter “Maeshoridisc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the THF-soluble component is 0.8% by mass. This sample solution is used for measurement under the following conditions.
Device: High-speed GPC device "HLC-8220GPC" [manufactured by Tosoh Corporation]
Column: LF-604 double eluent: THF
Flow rate: 0.6 ml/min
Oven temperature: 40°C
Sample injection volume: 0.020 ml
In calculating the molecular weight of the sample, a standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F- 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used.

<Measurement of acid value of binder resin>
The acid value is the number of mg of potassium hydroxide required to neutralize the acid contained in 1 g of the sample. The acid value of the binder resin is measured according to JIS K 0070-1992, and specifically, it is measured according to the following procedure.

(1) Preparation of reagent 1.0 g of phenolphthalein is dissolved in 90 ml of ethyl alcohol (95 vol%), and ion-exchanged water is added to 100 ml to obtain a phenolphthalein solution.

7 g of special grade potassium hydroxide is dissolved in 5 ml of water, and ethyl alcohol (95 vol%) is added to make 1 liter. It is placed in an alkali resistant container for 3 days so as not to come into contact with carbon dioxide gas and left for 3 days and then filtered to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali resistant container. Regarding the factor of the potassium hydroxide solution, 25 ml of 0.1 mol/l hydrochloric acid was placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution was added, and titration was performed with the potassium hydroxide solution to determine the potassium hydroxide solution required for neutralization. Calculate from the amount. As the 0.1 mol/l hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test 2.0 g of a crushed binder resin sample is precisely weighed in a 200 ml Erlenmeyer flask, 100 ml of a mixed solution of toluene/ethanol (2:1) is added, and the mixture is dissolved for 5 hours. .. Next, a few drops of a phenolphthalein solution is added as an indicator, and titration is performed using a potassium hydroxide solution. The end point of titration is when the light red color of the indicator continues for 30 seconds.

(B) Blank test The same titration as the above operation is performed except that the sample is not used (that is, only the mixed solution of toluene/ethanol (2:1) is used).

(3) The acid value is calculated by substituting the obtained result into the following formula.

A=[(CB)×f×5.61]/S
Here, A: acid value (mgKOH/g), B: amount of potassium hydroxide solution added in blank test (ml), C: amount of potassium hydroxide solution added in main test (ml), f: potassium hydroxide Solution factor, S: sample (g).

<Measurement of glass transition temperature of toner>
The glass transition temperature (Tg) of the toner is measured according to ASTM D3418-82 using a differential scanning calorimeter "Q1000" (manufactured by TA Instruments). The melting point of indium and zinc is used to correct the temperature of the position detector, and the heat of fusion of indium is used to correct the amount of heat.

Specifically, 5 mg of toner is precisely weighed and placed in an aluminum pan, and an empty aluminum pan is used as a reference. Modulation measurement is carried out in the measurement range of 20° C. to 140° C. at a temperature rising rate of 1° C./min and an amplitude temperature range of ±0.318° C./min. In this temperature rising process, a specific heat change is obtained in the temperature range of 20°C to 140°C.

The glass transition temperature (Tg) of the binder resin is the stairs of the glass transition and the straight line that is equidistant from the extended straight line of each baseline in the vertical axis before and after the specific heat change of the reversible specific heat change curve appears. It is the temperature at the point where the curves of the shape change portion intersect.

The glass transition temperature at the time of the first temperature rise was set to Tg1, the glass transition temperature at the time of the second temperature rise was Tg2, and the glass transition temperature before the exposure treatment with carbon dioxide was performed after cooling at a temperature decrease rate of 10°C/min after the temperature rise The glass transition temperature of the toner of No. 1 at the first temperature rise was set to Tg3.

<Specification of Binder Resin and Crystalline Resin Structure>
The structures of the binder resin and the crystalline resin were identified by using nuclear magnetic resonance spectroscopy ( ¹ H-NMR) [400 MHz, CDCl ₃ , room temperature (25° C.)]. Measuring device: FT NMR device JNM-EX400 (made by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0 μs
Frequency range: 10500Hz
Total number of times: 64 times

<Measurement of Content of Crystalline Resin in Binder Resin from Toner>
The content of the crystalline resin, the binder resin and a crystalline resin each nuclear magnetic resonance spectroscopy ^{(1 H-NMR)} groups nuclear magnetic resonance spectroscopy of the toner in the spectrum ^{(1 H-NMR)} the integral value of the spectrum Calculated.
Measuring device: FT NMR device JNM-EX400 (made by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0 μs
Frequency range: 10500Hz
Total number of times: 64 times

Hereinafter, the present invention will be described more specifically by way of examples. The present invention is not limited to the examples below. Note that Examples 25 and 27 are reference examples. Further , all the parts and% in Examples and Comparative Examples are based on mass unless otherwise specified. First, the crystalline resin used in the examples will be described.

<Production of crystalline resin 1>
While stirring and adding 100.0 parts of sebacic acid and 93.5 parts of 1,10-decanediol to a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction tube, a dehydration tube, and a decompression device. Heated to a temperature of 130°C. After adding 0.7 parts of titanium (IV) isopropoxide as an esterification catalyst, the temperature is raised to 160° C. and polycondensation is carried out for 5 hours. Then, the temperature was raised to 180° C., and the reaction was performed under reduced pressure until the desired molecular weight was obtained to obtain polyester (1).

Next, 100.0 parts of polyester (1) and 440.0 parts of dehydrated chloroform were added to a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introducing tube and completely dissolved. Then, 5.0 parts of triethylamine was added, and 15.0 parts of 2-bromoisobutyryl bromide was gradually added while cooling with ice. Then, the mixture was stirred at room temperature (25°C) for a whole day and night. The resin solution was gradually dropped into a container containing 550.0 parts of methanol to reprecipitate the resin component, followed by filtration, purification and drying to obtain polyester (2).

Then, in a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 100.0 parts of the polyester (2) obtained above, 300.0 parts of styrene, 3.5 parts of copper(I) bromide, Then, 8.5 parts of pentamethyldiethylenetriamine was added and the polymerization reaction was carried out at a temperature of 110° C. with stirring. When the desired molecular weight was reached, the reaction was stopped, and 250.0 parts of methanol was used for reprecipitation, filtration and purification to remove unreacted styrene and the catalyst. Then, it was dried by a vacuum dryer set at 50° C. to obtain a crystalline resin 1 which was a styrene block modified polyester. Table 1 shows the physical properties of the crystalline resin 1 thus obtained.

<Production of crystalline resin 2>
100.0 parts of sebacic acid and 93.5 parts of 1,9 nonanediol were added to a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction tube, a dehydration tube, and a decompression device, and the temperature was changed while stirring. Heated to 130°C. After adding 0.7 part of titanium (IV) isopropoxide, the temperature is raised to 160° C. and polycondensation is carried out for 5 hours. Then, the temperature was raised to 210° C., and the reaction was carried out until the desired molecular weight was obtained to obtain crystalline resin 2. Table 1 shows the physical properties of the crystalline resin 2 thus obtained.

<Production of Crystalline Resin 3, 5-8>
Crystalline resins 3 and 5 to 8 were obtained in the same manner as in the production method of the crystalline resin 1 except that the raw materials and the production conditions shown in Table 1 were changed. Table 1 shows the physical properties of the obtained crystalline resins 3 and 5-8.

<Production of crystalline resin 4>
100.0 parts of sebacic acid and 93.5 parts of 1,9-nonanediol were added to a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction tube, a dehydration tube, and a decompression device while stirring. Heated to a temperature of 130°C. After adding 0.7 part of titanium (IV) isopropoxide, the temperature is raised to 160° C. and polycondensation is carried out for 5 hours. 15.0 parts of acrylic acid and 140.0 parts of styrene were added dropwise over 1 hour. After maintaining stirring at 160° C. for 1 hour, the monomer of the styrene resin component was removed at 8.3 kPa for 1 hour. Then, the temperature was raised to 210° C., and the reaction was carried out until the desired molecular weight was obtained to obtain crystalline resin 4. Table 1 shows the physical properties of the crystalline resin 4 thus obtained.

<Production of Toner 1>
To 1300.0 parts of ion-exchanged water heated to a temperature of 60° C., 9.0 parts of tricalcium phosphate was added, and T.I. K. Using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the mixture was stirred at a stirring speed of 15,000 rpm to prepare an aqueous medium.

Further, the following binder resin materials were mixed with a propeller stirrer at a stirring speed of 100 rpm to mix them to prepare a mixed solution.
-Styrene 75.0 parts-n-butyl acrylate 25.0 parts-Crystalline resin 1 5.0 parts Next, in the above solution,
-Cyan colorant (CI Pigment Blue 15:3) 6.5 parts-Negative charge control agent (Bontron E-88, manufactured by Orient Chemical Co.) 0.5 part-Hydrocarbon wax (Tm=78°C) 9 0.0 parts/polar resin 5.0 parts (styrene-2-hydroxyethyl methacrylate-methacrylic acid-methyl methacrylate copolymer, acid value 10 mg KOH/g, Tg=80° C., Mw=15,000)
And then the mixture was warmed to a temperature of 65° C. before T. K. A polymerizable monomer composition was prepared by stirring with a homomixer (made by Tokushu Kika Kogyo Co., Ltd.) at a stirring speed of 10,000 rpm to dissolve and disperse.

Subsequently, the polymerizable monomer composition was charged into the aqueous medium, and 8.0 parts of perbutyl PV (10-hour half-life temperature 54.6° C. (manufactured by NOF Corporation)) was added as a polymerization initiator. T. at a temperature of 70°C. K. Using a homomixer, the mixture was stirred at a stirring speed of 15,000 rpm for 20 minutes and granulated.

The toner is transferred to a propeller-type stirrer and stirred at a stirring speed of 200 rpm for 5 hours at a temperature of 85° C. to polymerize styrene and n-butyl acrylate, which are polymerizable monomers in the polymerizable monomer composition, to give a toner. A slurry containing particles was produced. After the completion of the polymerization reaction, the slurry was cooled. Hydrochloric acid was added to the cooled slurry to adjust the pH to 1.4, and the calcium phosphate salt was dissolved by stirring for 1 hour. Thereafter, the slurry was washed with 10 times the amount of water, filtered and dried, and then the particle size was adjusted by classification to obtain toner particles. In the toner particles, 65.0 parts of styrene-acrylic resin, 35.0 parts of block polymer, 6.5 parts of cyan colorant, 9.0 parts of wax, 0.5 part of negative charge control agent. The negative charge control resin 1 was 0.7 parts and the polar resin was 5.0 parts.

Hydrophobic silica fine particles (primary particle diameter: 7 nm, BET specific surface area: 130 m ²⁾ treated with 20% by mass of dimethyl silicone oil as an external additive to 100.0 parts of the toner particles as an external additive. /G) 1.5 parts by mass was mixed with a Mitsui Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) for 15 minutes to obtain a toner before exposure to carbon dioxide. The stirring speed of the Mitsui Henschel mixer was 3000 rpm. The obtained toner before treatment was put into an apparatus as shown in FIG. 1 and held for 60 minutes in carbon dioxide at a temperature of 25° C. and a pressure of 2.5 MPa to perform an exposure treatment with carbon dioxide. Thereafter, the pressure control valve was opened and the pressure was reduced to atmospheric pressure, whereby Toner 1 was obtained. Table 2 shows the physical properties of Toner 1 thus obtained.

<Production of Toners 2 to 28 and Toners 30 to 35>
Toners 2 to 28 and Toners 30 to 35 were obtained by the same manufacturing method as that of Toner 1, except that the raw materials and the number of parts added were changed as shown in Tables 2 and 3.

<Production of Toner 29>
Styrene-acrylic resin 100.0 parts (styrene:n-butyl acrylate=75:25 (mass ratio) copolymer) (Mw=15,000)
-Crystalline resin 2 5.0 parts-Methyl ethyl ketone 100.0 parts-Ethyl acetate 100.0 parts-Hydrocarbon wax (Tm=78°C) 9.0 parts-Cyan colorant (CI Pigment Blue 15:3) ) 6.5 parts/negative-charge control resin 1 1.0 part The above materials were dispersed for 3 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.) to obtain a colorant dispersion liquid.

On the other hand, 27.0 parts of calcium phosphate was added to 3000.0 parts of ion-exchanged water heated to a temperature of 60° C., and stirred at a stirring speed of 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). , An aqueous medium was prepared. Was charged with the colorant dispersion into the aqueous medium, temperature 65 ° C., under N ₂ atmosphere, T. K. The colorant particles were granulated by stirring with a homomixer at a stirring speed of 12,000 rpm for 15 minutes. After that, T. K. The homomixer was changed to a normal propeller stirrer, the stirring speed of the stirrer was maintained at 150 rpm, the internal temperature was raised to 95°C and the temperature was maintained for 3 hours to remove the solvent from the dispersion liquid and disperse the toner particles. A liquid was prepared.

Hydrochloric acid was added to the obtained dispersion liquid of the toner particles to adjust the pH to 1.4, and the calcium phosphate salt was dissolved by stirring for 1 hour. The dispersion was filtered and washed with a pressure filter to obtain a toner aggregate. Then, the toner aggregates were crushed and dried to obtain toner particles. The toner particles contained 65.0 parts of styrene-acrylic resin, 35.0 parts of block polymer, 6.5 parts of cyan colorant, 9.0 parts of wax, 1.0 part of negative charge control resin 1. Was included. With respect to 100.0 parts of the obtained toner particles, hydrophobic silica fine particles (primary particle diameter: 7 nm, BET specific surface area: 130 m ^{2 /} g) of 1.5 parts was mixed with a Mitsui Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at a stirring speed of 3000 rpm for 15 minutes to obtain an unprocessed toner. The obtained toner before treatment was put into an apparatus as shown in FIG. 2 and exposed to carbon dioxide at a temperature of 15° C. and a pressure of 2.5 MPa for 180 minutes for exposure treatment. Thereafter, the pressure adjusting valve was opened and the pressure was reduced to atmospheric pressure, whereby Toner 29 was obtained. Table 3 shows the physical properties of Toner 29 thus obtained.

St: styrene, n-BA: butyl acrylate, MMA: methyl methacrylate, MAA: methacrylic acid, EHA: 2-ethylhexyl acrylate.

<Image evaluation>
The image evaluation was performed by partially modifying a color laser printer (Color LaserJet 3525dn) manufactured by HP. The modification was made to work even if only one color process cartridge was installed. In addition, the fixing device was modified so that it could be changed to any temperature. The toner inside was extracted from the process cartridge for black toner mounted on this color laser printer, and the inside was cleaned by air blow. Then, each toner (300 g) was introduced into the process cartridge, the process cartridge in which the toner was refilled was mounted in the color laser printer, and the following image evaluation was performed. The specific image evaluation items are as follows.

[Low temperature fixability]
A solid image (toner application amount: 0.9 mg/cm ² ) was printed on the transfer material while changing the fixing temperature, and evaluated according to the following criteria. The fixing temperature is a value measured on the surface of the fixing roller using a non-contact thermometer. As the transfer material, LETTER size plain paper (XEROX 4200, manufactured by XEROX, 75 g/m ² ) was used.

(Evaluation criteria)
A: No offset at 100°C B: Offset at 100°C C: Offset at 110°C D: Offset at 120°C

[Defective overcharge image (defective regulation)]
Under a low temperature and normal humidity environment (temperature 10° C./humidity 10% RH), 35,000 sheets of images with a print rate of 1% along horizontal lines were printed out. After the test, a halftone (toner application amount: 0.6 mg/cm ² ) image was printed out on a LETTER size XEROX 4200 paper (manufactured by XEROX, 75 g/m ² ). The presence or absence of lumpy toner on the developing blade due to spot-like streaks appearing on the image printed out and defective regulation of toner was evaluated.

(Evaluation criteria)
A: Not generated B: No spot-like streaks, but there are a few small toner clusters C: There are a few spot-like streaks at the edges, or there are 4, 5 small toner clusters D: Entire surface There are speckled streaks, or small toner clusters or more than 5 spots or clear toner clusters.

[Effect of electrostatic charge leakage image (fogging)]
Under a high-temperature and high-humidity environment (temperature: 33° C./humidity: 85% RH), a printout test was performed on 35,000 sheets of images with a horizontal line of 1% print ratio. After the test was completed, the sample was left for 48 hours, and then the reflectance (%) of the non-image portion of the image printed out was measured by "REFLECTOMETER MODEL TC-6DS" (manufactured by Tokyo Denshoku Co., Ltd.). The obtained reflectance was evaluated using a numerical value (%) subtracted from the reflectance (%) of an unused printout paper (standard paper) measured in the same manner. The smaller the value, the more the image fogging is suppressed. The evaluation was carried out in plain paper mode (HP Brochure Paper 200 g, Glossy, manufactured by HP, 200 g/m ² ) in gloss paper mode.

(Evaluation criteria)
A: less than 0.5% B: 0.5% or more and less than 1.5% C: 1.5% or more and less than 3.0% D: 3.0% or more

〔blocking〕
5 g of each toner was placed in a 50 cc resin cup and left standing for 3 days at a temperature of 60° C. and a humidity of 10% RH, and the presence or absence of aggregates was examined and evaluated according to the following criteria.

(Evaluation criteria)
A: No agglomerates were generated B: Minor agglomerates were generated and collapsed when pressed lightly with a finger C: Agglomerates were generated, did not collapse even when lightly pressed with a finger D: Completely agglomerated

<Measurement of coarse particles in toner>
The coarse particles in the toner were measured as follows. By suctioning 0.5 g of the toner particles with a vacuum cleaner, the toner particles are passed through a metal mesh (400 mesh) having a diameter of 10 mm. At this time, the toner particles remaining on the mesh are made into coarse particles, which is taped, and what is attached to the paper is enlarged with a KEYENCE microscope to count the coarse particles.

The number (j) of coarse particles was measured and judged according to the following criteria.
(Evaluation criteria)
A: 0≦j<50
B: 50≦j<100
C: 100≦j<150
D:150≦j

[Examples 1 to 29]
In Examples 1 to 29, the above evaluations were performed using Toners 1 to 29, respectively. The evaluation results are shown in Table 4.

[Comparative Examples 1 to 5]
In Comparative Examples 1 to 5, the above evaluations were performed using Toners 30 to 34, respectively. The evaluation results are shown in Table 4. In the toner 32 of Comparative Example 3, toner particles were melted and coalesced to generate coarse particles, and therefore low-temperature fixability, defective overcharged image (defective regulation), fog and blocking were not evaluated.

[Reference example]
As a reference example, the above evaluation was performed using Toner 35. The evaluation results are shown in Table 4.

Claims (6)

A method for producing a toner having toner particles having a binder resin and a crystalline resin, comprising:
The manufacturing method includes the following carbon dioxide exposure treatment step (i) or (ii),
(I) Carbon dioxide having a temperature of 10° C. or higher and 60° C. or lower and a pressure of 1.0 MPa or higher and 3.5 MPa or lower is exposed to the toner particles having a binder resin and a crystalline resin before exposure to carbon dioxide for 5 minutes or longer and 180 minutes or shorter. To obtain toner;
(Ii) Carbon dioxide having a temperature of 10° C. or more and 60° C. or less and a pressure of 1.0 MPa or more and 3.5 MPa or less is added to the toner before the carbon dioxide exposure treatment having the toner particles having the binder resin and the crystalline resin and the external additive. A step of obtaining toner by exposing for 5 minutes or more and 180 minutes or less ;
Acid value before Kiyuigi resin, not more than 15.0 mg KOH / g,
The absolute value (ΔSP value) of the difference between the SP value of the binder resin and the SP value of the crystalline resin is 0.03 or more and 0.20 or less,
A method for producing a toner, wherein the glass transition temperatures (Tg1, Tg2) of the toner in differential scanning calorimetry (DSC) satisfy the following formulas (1) and (2).
Tg1≧50°C (1)
0.60≦Tg2/Tg1≦0.85 (2)
(In formulas (1) and (2),
Tg1 represents the glass transition temperature at the first temperature rise in the DSC measurement of the toner.
Tg2 represents the glass transition temperature at the second temperature rise in the DSC measurement of the toner. ) The method for producing a toner according to claim 1, wherein the toner particles before the carbon dioxide exposure treatment in (i) or the toner particles in (ii) satisfy the following expression (4).
Tg1-Tg3≧2° C. (4)
(In the formula (3), Tg3 is the toner particle before the carbon dioxide exposure treatment in the above (i) or the toner particle in the above (ii) during the first temperature rise in the differential scanning calorimetry (DSC)). Indicates the glass transition temperature.) The weight average molecular weight of the binder resin (Mw) The method for producing a toner according to claim 1 or 2 is 10000 50,000. The content of the crystalline resin, method for producing a toner according to any one of the binder resin 100 parts by mass with respect to 2.0 part by mass 25.0 parts by mass or less is claims 1-3. The crystalline resin, method for producing a toner according to any one of claims 1 to 4 having a unit represented by the following formula (3).

(In the formula (3), m and n each independently represent an integer of 4 or more and 16 or less.) The toner particles before the carbon dioxide exposure process in (i) or the toner particles in the (ii),, the following processes (a) and (b):
(A) Granulation step of dispersing a polymerizable monomer composition having a polymerizable monomer and the crystalline resin in an aqueous medium to form droplets of the polymerizable monomer composition (b) ) the toner manufacturing method according to any one of the droplets in the polymerizable monomer claim body obtained Ru by polymerization step of polymerizing the 1-5.

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