JP2023126108A - Resin particle, toner, developer, toner storage unit, image formation device and image formation method - Google Patents

Abstract

To provide resin particles which suppress environmental loads, are excellent in low temperature fixability and charging property even by using a plant-derived resin, and enable formation of an image having excellent image quality.SOLUTION: Resin particles are resin particles containing polyethylene terephthalate or polybutylene terephthalate, wherein concentration of radioactive carbon isotope 14C of the resin particles is 10.8 pMC or more, and 0.05-1 mass% of a divalent metal element which is contained in the resin particles and excludes an external additive is contained.SELECTED DRAWING: None

Description

The present invention relates to resin particles, toner, developer, toner storage unit, image forming apparatus, and image forming method.

Resin particles are widely used as toner for image forming devices such as multifunction peripherals (MFPs) and printers in various places such as offices. In order to reduce the environmental impact of toner, for example, we have improved the toner's low-temperature fixing properties to reduce power consumption, reduced energy consumption during manufacturing, used biomass (plant)-derived resin as a binder, and The use of recycled raw materials for resin is being considered. In particular, there is an increasing demand for the use of recycled raw materials in binder resins, as the need for resource conservation, energy conservation, and resource recycling is becoming more important.

As a toner containing a binder resin produced using recycled raw materials, for example, an amorphous polyester toner resin containing a depolymerized PET polyol and a second toner resin containing a depolymerized recycled PET polyol and a bio-based polyester or polyacid are used. Toner particles containing an amorphous resin and a crystalline resin containing depolymerized recycled PET polyol are disclosed (see Patent Document 1).

However, in the toner particles of Patent Document 1, there is a large difference in composition between bio-based polyester or polyacid and non-biobased polyester or polyacid, so there is a difference in the aggregation state of the toner during aggregation during toner production. There was a problem that the particle size distribution was easily deteriorated.

One aspect of the present invention is to provide resin particles that have a reduced environmental impact, have excellent low-temperature fixing properties and charging properties, and can form images with excellent image quality even when using a plant-derived resin. purpose.

One embodiment of the resin particles according to the present invention is
Resin particles containing polyethylene terephthalate or polybutylene terephthalate,
The radiocarbon isotope ^14C concentration of the resin particles is 10.8 pMC or more,
The resin particles contain 0.05% by mass to 1% by mass of divalent metal elements excluding external additives.

One aspect of the present invention is to provide resin particles that can produce toners that have reduced environmental impact, have excellent low-temperature fixing properties and charging properties, and can form images with excellent image quality even when using plant-derived resins. can be provided.

1 is a schematic configuration diagram showing an example of an image forming apparatus according to an embodiment. FIG. 2 is a schematic configuration diagram showing another example of an image forming apparatus according to an embodiment. 1 is a schematic configuration diagram showing an example of an image forming apparatus according to an embodiment. 4 is a partially enlarged view of the image forming apparatus of FIG. 3. FIG. FIG. 1 is a schematic configuration diagram showing an example of a process cartridge according to an embodiment.

Embodiments of the present invention will be described in detail below. Note that the embodiments are not limited to the following description, and can be modified as appropriate without departing from the gist of the present invention. In addition, in this specification, "~" indicating a numerical range means that the lower limit and upper limit include the numerical values written before and after it, unless otherwise specified.

<Resin particles>
The resin particles according to one embodiment will be explained. The resin particles according to one embodiment include polyethylene terephthalate (PET) or polybutylene terephthalate (PBT). In addition to PET or PBT, the resin particles according to one embodiment preferably contain at least one of an amorphous resin, an amorphous resin, and a crystalline resin, and may optionally contain other additives such as external additives. It may contain ingredients.

(Radioactive carbon isotope ^14C concentration)
The radiocarbon isotope ¹⁴ C concentration (hereinafter sometimes referred to as " ¹⁴ C concentration") of the resin particles according to one embodiment is 10.8 pMC or more, preferably 11 pMC or more, more preferably 20 pMC or more, and 30 pMC or more. The above is more preferable. If the radiocarbon isotope ¹⁴ C concentration of the resin particles is less than 10.8 pMC, the degree of biomass described below is generally perceived to be low, making it impossible to reduce the burden on the environment.

¹⁴ C concentration exists in nature (in the atmosphere), is taken in by photosynthesis while plants are active, and is in equilibrium with the ¹⁴ C concentration present in the atmosphere (107.5 pMC). However, from the stage when organisms cease their life activities, photosynthetic uptake stops, and ^{the 14} C concentration decreases according to the half-life of ¹⁴ C, which is 5,730 years. Since fossil resources derived from living organisms have ceased life activity for tens of thousands to hundreds of millions of years, ¹⁴ C concentrations are hardly detected.

Here, "pMC" is an abbreviation for percent modern carbon, and the ratio of ¹⁴ C to ¹² C ( ¹⁴ C/ ¹² C) in biomass in 1950 was defined as 100 pMC. be. However, since the current concentration of carbon-14 ( ¹⁴ C) in the atmosphere is increasing year by year, it is stipulated that this value be multiplied by a coefficient for correction. The correction coefficient shall be determined according to the year.

The ¹⁴ C concentration can also be expressed as the degree of biomass calculated by the following formula (1).
Biomass degree (%) = ^14C concentration (pMC)/107.5×100... Formula (1)

^{The 14} C concentration of 10.8 pMC or more means that the biomass degree is 10% or more. The biomass degree of 10% or more is a desired concentration from the viewpoint of carbon neutrality.

The method for measuring the ¹⁴ C concentration is not particularly limited and can be appropriately selected depending on the purpose, but radiocarbon dating is particularly preferred.

The measurement procedure for radiocarbon dating is to burn resin particles and reduce carbon dioxide (CO ₂ ) to obtain graphite (C). ^{The 14} C concentration of graphite is measured using an accelerator mass spectrometer (AMS, manufactured by Beta Analytic). This AMS measurement is disclosed in, for example, Japanese Patent No. 4050051.

(Content of divalent metal elements)
The resin particles according to one embodiment contain 0.05% by mass to 1% by mass of a divalent metal element excluding external additives. The content of the divalent metal element is preferably 0.07% by mass to 0.80% by mass, preferably 0.10% by mass to 0.70% by mass, and 0.20% by mass to 0.65% by mass. More preferred.

Divalent metal elements are typical elements belonging to Group 2 of the periodic table, and include beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). include. Divalent metal elements are included when inorganic fine particles and polymeric fine particles are used as external additives, when a metal salt of a divalent metal is used as a flocculant, when a flocculation stopper is used, etc.

[Content of divalent metal element in resin particles]
The metal ion of the divalent metal element contained in the resin particles according to one embodiment can be determined by any method, and can be calculated using a fluorescent X-ray apparatus or ICP-AES. For example, quantitative analysis of metal ions was performed using a fluorescent X-ray device (ZSX Primus IV (manufactured by Rigaku Corporation)). The form of the resin particle sample to be measured is not particularly limited, but it is easier to handle if it is molded into a pellet or sheet shape using a general pressure molding machine or the like. For example, a sample was placed in a tablet molding die with a diameter of 15 mm, and the sample was pressed under a load of 6 MPa for 1 minute to obtain a pellet tablet of resin particles with a thickness of about 2 mm. By placing the obtained pellet tablet in a sample holder of a fluorescent X-ray device and performing quantitative analysis measurement, it is possible to detect the metal element contained in the sample. When external additives are added to the resin particles, the amount of metal elements is measured after removing the external additives from the resin particles. Any method can be used to remove the external additive, but for example, 3.75 g of resin particles are added to 50 ml of a surfactant (Noigen ET-165) diluted to 0.5%, and the mixture is stirred in a ball mill. Thereafter, ultrasonic energy (40 W, 5 minutes) is applied using an ultrasonic homogenizer. After centrifuging the ultrasonicated resin dispersion solution, it is filtered to collect the precipitate. At this time, repeat the above steps until the supernatant liquid after centrifugation becomes clear. Thereafter, the amount of metal elements is measured using the sample dried in a constant temperature bath.

The resin particles according to one embodiment may contain external additives as other components, as described below. When the external additive contains a divalent metal element, the content of the divalent metal element contained in the resin particles is the remaining divalent metal element excluding the external additive. That is, the resin particles according to one embodiment preferably contain 0.05% by mass to 1% by mass of the divalent metal element remaining after excluding the external additive.

Among the divalent metal elements, the content of Mg is preferably 0.1% to 0.5% by mass, more preferably 0.15% to 0.45% by mass, and 0.1% to 0.5% by mass, more preferably 0.15% to 0.45% by mass, and More preferably, the amount is from .2% by mass to 0.4% by mass.

When the resin particles contain Na, it is preferable that Mg among the divalent metal elements is contained in a larger amount than Na, and the Na content exceeds 0.05% by mass.

[PET or PBT]
PET or PBT contained in the resin particles according to one embodiment is mainly contained in the resin particles to reduce environmental load.

PET or PBT is not particularly limited and can be selected as appropriate depending on the purpose. For example, recycled products, off-spec textile waste, or pellets can be used, but from the viewpoint of reducing environmental load, It is preferable that a recycled product (hereinafter sometimes referred to as "recycled resin") is processed into flakes.

Note that in this specification, biomass-derived resins and recycled resins may be collectively referred to as "environmentally friendly resins."

There are no particular restrictions on the molecular weight distribution, composition, manufacturing method, form of use, etc. of PET or PBT, and they can be appropriately selected depending on the purpose.

The weight average molecular weight (Mw) of PET or PBT is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 30,000 to 100,000.

The analysis method and calculation method for the content of PET or PBT in the resin particles are not particularly limited, and a general method for calculating the blending amount of PET can be used. As a method for analyzing and calculating the content of PET or PBT, for example, the resin particles are separated by gel permeation chromatography (GPC), etc., and each separated component is analyzed using the analysis method described below. The mass ratio of the constituent components can be calculated.

In addition, the ester bonds in the resin particles were methylated using a gas chromatography mass spectrometry (GC/MS) method at 300°C using a reaction reagent (10% tetramethyl ammonium hydroxide (TMAH)/methanol solution). Quantitative analysis can also be performed by estimating the main components from soft decomposition and drawing a calibration curve of total ion current chromatogram (TICC) intensity.

Separation of each component by GPC can be performed, for example, by the following method.

In GPC measurement using tetrahydrofuran (THF) as a mobile phase, the eluate is fractionated using a fraction collector or the like, and fractions corresponding to a desired molecular weight portion of the total area of the elution curve are collected.

After concentrating and drying the combined eluate using an evaporator or the like, the solid content is dissolved in a heavy solvent such as heavy chloroform or heavy THF, and ¹ H-NMR measurement is performed. From the integral ratio of each element, the resin in the eluted component is determined. Calculate the constituent monomer ratio of.

Another method is to concentrate the eluate, then hydrolyze it with sodium hydroxide, etc., and perform qualitative and quantitative analysis of the decomposition products using high performance liquid chromatography (HPLC), etc. to calculate the constituent monomer ratio. You can also.

The content of PET or PBT is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably 5 parts by mass to 70 parts by mass, and 10 parts by mass to 50 parts by mass, based on 100 parts by mass of resin particles. Parts by mass are more preferred. When the content of PET or PBT is 70 parts by mass or less based on 100 parts by mass of resin particles, low-temperature fixability can be exhibited. When the content of PET or PBT is 5 parts by mass or more based on 100 parts by mass of resin particles, the effect of reducing environmental load can be exhibited, and the resin particles can have an excellent particle size distribution. When the content of PET or PBT is within the above-mentioned more preferable range, it is advantageous in that both a reduction in the environmental load of the resin particles and an improvement in the particle size distribution can be achieved.

An example of a means for separating each component contained in resin particles when analyzing resin particles according to an embodiment will be shown in detail. First, 1 g of resin particles is poured into 100 mL of THF, and the mixture is stirred at 25° C. for 30 minutes to obtain a solution in which soluble components are dissolved. The solution is filtered through a membrane filter with an opening of 0.2 μm to obtain the THF-soluble content in the resin particles. Next, this is dissolved in THF to prepare a sample for GPC measurement, and the sample is injected into the GPC used to measure the molecular weight of each resin described above. On the other hand, place a fraction collector at the eluate outlet of the GPC and separate the eluate at predetermined counts. get. Then, for each elution, 30 mg of sample is dissolved in 1 mL of deuterated chloroform, and 0.05% by volume of tetramethylsilane (TMS) is added as a reference substance. The solution is filled into a glass tube for NMR measurement with a diameter of 5 mm, and using a nuclear magnetic resonance apparatus (JNM-AL400 manufactured by JEOL Ltd.), integration is performed 128 times at a temperature of 23°C to 25°C to obtain a spectrum. . The composition and composition ratio of monomers such as PET resin contained in the resin particles can be determined from the peak integral ratio of the obtained spectrum.

[Biomass-derived resin]
The resin particles according to one embodiment preferably contain biomass-derived resin. The biomass-derived resin may be included in at least one of an amorphous resin, an amorphous resin, and a crystalline resin, which will be described later.

A biomass-derived resin is a resin containing a plant-derived compound as a raw material. The biomass-derived resin may be contained in the crystalline resin described below, may be contained in the amorphous resin, or may be contained in other components such as a mold release agent. By adjusting the ratio of petroleum-derived components and plant-derived components of the alcohol component and acid component that make up the resin particles, the environmentally friendly ratio described below and the toner when the resin particles are applied to the toner. Quality can be adjusted.

In recent years, there has been a strong demand for resins, including biomass-derived resins, to improve their functionality as toners while increasing their environmental friendliness. Many petroleum-based resins have aromatic ring skeletons in their constituent monomers. However, when biomass-derived resins require low-temperature fixability, aliphatic monomers that do not have an aromatic ring skeleton are often used as constituent monomers. Therefore, there is a problem that the structural difference is large and the particle size distribution becomes poor during the production of resin particles.

In response to the above problem, the resin particles according to one embodiment contain PET or PBT having an aromatic ring skeleton, thereby making it possible to reduce structural differences between biomass-derived resins while increasing environmental friendliness. Furthermore, when a metal salt is used to agglomerate resin fine particles during the production of resin particles, if a trivalent or higher valent metal salt with a high degree of crosslinking is used, the aggregation property tends to vary and the particle size distribution deteriorates. By mild aggregation using a divalent metal salt, resin particles with a good particle size distribution can be obtained.

Therefore, the resin particles according to one embodiment can reduce environmental impact and have an excellent particle size distribution.

As described above, the resin particles according to one embodiment preferably contain at least one of an amorphous resin, an amorphous resin, and a crystalline resin in addition to PET or PBT; It is more preferable that the resin contains a synthetic resin and a crystalline resin.

The total content of the biomass-derived resin and PET or PBT relative to the total mass of the resin particles is preferably 50% by mass or more, more preferably 60% by mass or more, and 80% by mass or more. is even more preferable.

As described above, the resin particles according to one embodiment contain PET or PBT and a biomass-derived resin, but it is preferable that PET or PBT is contained in a larger amount than the biomass-derived resin.

[Amorphous resin]
It is preferable that the resin particles according to one embodiment include an amorphous resin.

The amorphous resin is preferably a terpene resin or an amorphous (non-crystalline) polyester resin (hereinafter also referred to as "amorphous polyester resin B"), especially a linear polyester resin, and an unmodified polyester resin. Resins are preferred. Furthermore, environmentally friendly resins are preferred. In this embodiment, the amorphous resin refers to anything other than PET or PBT.

An unmodified polyester resin is a polyester resin obtained using a polyhydric alcohol and a polyhydric carboxylic acid such as a polyhydric carboxylic acid, a polycarboxylic acid anhydride, a polyhydric carboxylic acid ester, or a derivative thereof, It is a polyester resin that has not been modified with isocyanate compounds or the like.

The amorphous polyester resin preferably does not have urethane bonds or urea bonds.

The amorphous polyester resin preferably contains a dicarboxylic acid component as a constituent, and the dicarboxylic acid component preferably contains 50 mol% or more of terephthalic acid. This is advantageous in terms of heat-resistant storage stability.

Examples of polyhydric alcohols include diols and the like.

Examples of the diol include polyoxypropylene (2.2)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene (2.2)-2,2-bis(4-hydroxyphenyl)propane, etc. Alkylene (carbon number 2-3) oxide (average number of added moles 1-10) adduct of bisphenol A; ethylene glycol, neopentyl glycol, propylene glycol; Hydrogenated bisphenol A, alkylene (carbon number 2) of hydrogenated bisphenol A ~3) Oxide (average number of moles added 1 to 10) adducts, etc.

These may be used alone or in combination of two or more.

Among these, it is preferable to include plant-derived ethylene glycol and propylene glycol.

Examples of polyhydric carboxylic acids include dicarboxylic acids.

Examples of dicarboxylic acids include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, maleic acid; alkyl groups having 1 to 20 carbon atoms or alkenyl groups having 2 to 20 carbon atoms, such as dodecenylsuccinic acid and octylsuccinic acid; Examples include succinic acid substituted with , modified purified rosin, and the like. As the modified purified rosin, those modified with acrylic acid, fumaric acid, and maleic acid are preferred.

Among these, it is preferable to include saturated aliphatic succinic acid derived from plants and modified purified rosin. By being derived from plants, carbon neutrality can be enhanced. Saturated aliphatics have the effect of increasing the recrystallization property of the crystalline polyester resin, and can increase the aspect ratio of the crystalline polyester resin and improve the low-temperature fixability.

These may be used alone or in combination of two or more.

Further, for the purpose of adjusting the acid value and hydroxyl value, the amorphous polyester resin may contain at least one of a trivalent or higher carboxylic acid and a trivalent or higher alcohol at the end of the resin chain.

Examples of trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, and acid anhydrides thereof.

Examples of trihydric or higher alcohols include glycerin, pentaerythritol, trimethylolpropane, and the like.

The molecular weight of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose. In gel permeation chromatography (GPC) measurement, the weight average molecular weight (Mw) is preferably 3,000 to 10,000. The number average molecular weight (Mn) is preferably 1,000 to 4,000. The ratio Mw/Mn of weight average molecular weight (Mw) to number average molecular weight (Mn) is preferably 1.0 to 4.0.

When the molecular weight is at least the above lower limit, it is possible to prevent the resin particles from deteriorating in their heat-resistant storage stability and durability against stress such as stirring in a developing machine. When the molecular weight is less than or equal to the above upper limit, it is possible to prevent the viscoelasticity of the resin particles from increasing when melted and to prevent the low-temperature fixability from decreasing.

The weight average molecular weight (Mw) is more preferably 4,000 to 7,000. The number average molecular weight (Mn) is more preferably 1,500 to 3,000. The ratio Mw/Mn of weight average molecular weight (Mw) to number average molecular weight (Mn) is more preferably 1.0 to 3.5.

The acid value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose. 1 mgKOH/g to 50 mgKOH/g is preferable, and 5 mgKOH/g to 30 mgKOH/g is more preferable. When the acid value is 1 mgKOH/g or more, the resin particles tend to be negatively charged, and furthermore, when fixing to paper, the affinity between the paper and the resin particles improves, and low-temperature fixing properties can be improved. can. When the acid value is 50 mgKOH/g or less, charging stability, particularly charging stability against environmental changes, can be prevented from deteriorating.

The hydroxyl value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 mgKOH/g or more.

The glass transition temperature (Tg) of the amorphous polyester resin is preferably 40°C to 80°C, more preferably 50°C to 70°C. By having a glass transition temperature (Tg) of 40°C or higher, the resin particles have sufficient heat-resistant storage stability and durability against stress such as stirring in a developing machine, and also have good filming resistance. . When the glass transition temperature (Tg) is 80° C. or less, the resin particles are sufficiently deformed by heating and pressure during fixing, and low-temperature fixability is improved.

The molecular structure of the amorphous polyester resin can be confirmed by X-ray diffraction, GC/MS, LC/MS, IR measurement, etc. in addition to NMR measurement using a solution or solid. A simple method is to detect amorphous polyester resin that does not have absorption based on δ _CH (out-of-plane bending vibration) of olefin at 965 ± 10 cm ^-1 and 990 ± 10 cm ^-1 in an infrared absorption spectrum. It will be done.

The content of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably 50 parts by mass to 90 parts by mass, and 60 parts by mass to 100 parts by mass of the resin particles. 80 parts by mass is more preferred. When the content is 50 parts by mass or more, it is possible to suppress deterioration of the dispersibility of the pigment and the release agent in the resin particles, and it is possible to suppress the occurrence of fogging and disturbance of images. When the content is 90 parts by mass or less, it is possible to prevent the contents of the crystalline polyester resin C and the amorphous polyester resin B from decreasing, thereby suppressing a decrease in low-temperature fixability. When the content is within the more preferred range, it is advantageous in that both high image quality and low-temperature fixability are excellent.

[Amorphous resin (prepolymer)]
The resin particles according to one embodiment may include an amorphous resin (prepolymer) to improve low-temperature fixability.

Examples of the reactive precursor include polyesters having groups capable of reacting with active hydrogen groups.

Examples of groups capable of reacting with active hydrogen groups include isocyanate groups, epoxy groups, carboxylic acids, and acid chloride groups. Among these, isocyanate groups are preferred since they can introduce urethane bonds or urea bonds into the amorphous polyester resin.

The reactive precursor may have a branched structure provided by at least one of a trihydric or higher alcohol and a trivalent or higher carboxylic acid.

Examples of polyester resins containing isocyanate groups include reaction products between polyester resins containing active hydrogen groups and polyisocyanates.

A polyester resin having an active hydrogen group can be obtained, for example, by polycondensing a diol, a dicarboxylic acid, and at least one of a trihydric or higher alcohol and a trivalent or higher carboxylic acid. The trihydric or higher alcohol and the trivalent or higher carboxylic acid impart a branched structure to the polyester resin containing an isocyanate group.

Examples of the diol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 3- Aliphatic diols such as methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol; diethylene glycol, triethylene glycol, dipropylene Diols with oxyalkylene groups such as glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; Alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; Alicyclic diols with ethylene oxide and propylene oxide , butylene oxide and other alkylene oxides; bisphenols such as bisphenol A, bisphenol F, and bisphenol S; bisphenols with alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide added to bisphenols; Examples include oxide adducts. Among these, from the viewpoint of controlling the glass transition temperature (Tg) of the amorphous polyester resin A to 20°C or less, for example, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, It is preferable to use aliphatic diols having 3 to 10 carbon atoms, such as 2-methyl-1,3-propanediol, 1,5-pentanediol, and 3-methyl-1,5-pentanediol. It is more preferable to use 50 mol% or more of the alcohol component. These diols may be used alone or in combination of two or more.

Since the amorphous polyester resin A has steric hindrance in its resin chain, the melt viscosity at the time of fixing is lowered, and low-temperature fixability is more easily exhibited. Therefore, it is preferable that the main chain of the aliphatic diol has a structure represented by the following general formula (1).
HO-(CR ¹ R ² ) _n -OH...General formula (1)
However, in the general formula (1), R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. n represents an odd number from 3 to 9. In the n repeating units, R ¹ and R ² may be the same or different.

Here, the main chain of an aliphatic diol is a carbon chain connected by the shortest number between two hydroxyl groups of the aliphatic diol. It is preferable that the number of carbon atoms in the main chain is odd, since crystallinity decreases due to even-oddness. Further, it is more preferable to have at least one alkyl group having 1 to 3 carbon atoms in the side chain, since the interaction energy between main chain molecules is lowered due to stericity.

Examples of dicarboxylic acids include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, dodecanedioic acid, maleic acid, and fumaric acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalene dicarboxylic acid. etc. Further, anhydrides, lower alkyl esters (having 1 to 3 carbon atoms), and halides of these may also be used. Among these, from the viewpoint of controlling the glass transition temperature (Tg) of the amorphous polyester resin A to 20°C or less, aliphatic dicarboxylic acids having 4 to 12 carbon atoms are preferred, and 50% by mass of the carboxylic acid component in the resin It is more preferable to use % or more. These dicarboxylic acids may be used alone or in combination of two or more.

Examples of trivalent or higher alcohols include trivalent or higher aliphatic alcohols such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol; trivalent or higher polyphenols such as trisphenol PA, phenol novolac, and cresol novolac. Types include alkylene oxide adducts of trivalent or higher polyphenols, such as those obtained by adding alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, etc. to trivalent or higher polyphenols.

Examples of trivalent or higher carboxylic acids include trivalent or higher aromatic carboxylic acids, particularly trivalent or higher aromatic carboxylic acids having 9 to 20 carbon atoms such as trimellitic acid and pyromellitic acid. is preferred. Further, anhydrides, lower alkyl esters (having 1 to 3 carbon atoms), and halides of these may also be used.

Examples of the polyisocyanate include diisocyanate, trivalent or higher valent isocyanate, and the like.

The polyisocyanate is not particularly limited and can be selected as appropriate depending on the purpose, for example, 1,3- and/or 1,4-phenylene diisocyanate, 2,4- and/or 2,6-tolylene diisocyanate. Isocyanate (TDI), crude TDI, 2,4'- and/or 4,4'-diphenylmethane diisocyanate (MDI), crude MDI [crude diaminophenylmethane] condensation product of formaldehyde and aromatic amines (aniline) or mixtures thereof A mixture of diaminodiphenylmethane and a small amount (for example, 5 to 20% by mass) of a trifunctional or higher functional polyamine]], phosgenated product: polyallyl polyisocyanate (PAPI)], 1,5-naphthylene diisocyanate, 4,4', Aromatic diisocyanates such as 4"-triphenylmethane triisocyanate, m- and p-isocyanatophenylsulfonyl isocyanate; ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane Triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis(2-isocyanatoethyl) fumarate, bis(2-isocyanatoethyl) carbonate, 2- Aliphatic diisocyanates such as isocyanatoethyl-2,6-diisocyanatohexanoate; isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate ( alicyclic diisocyanates such as hydrogenated TDI), bis(2-isocyanatoethyl)-4-cyclohexene-1,2-dicarboxylate, 2,5- and 2,6-norbornane diisocyanate; Aroaliphatic diisocyanates such as diisocyanate (XDI) and α, α, α', α'-tetramethylxylylene diisocyanate (TMXDI); Polyisocyanate: Examples include modified products of these isocyanates, and mixtures of two or more of these may be used. Examples of modified products of the isocyanate include urethane groups, carbodiimide groups, allophanate groups, urea groups, biuret groups, etc. Examples include modified products containing a group, a uretdione group, a uretimine group, an isocyanurate group, and an oxazolidone group.

[Crystalline resin]
It is preferable that a crystalline resin is added to the resin particles according to one embodiment in order to improve low-temperature fixability.

The crystalline resin is not particularly limited as long as it has crystallinity, and can be appropriately selected depending on the purpose. Examples include polyester resin, polyurethane resin, polyurea resin, polyamide resin, polyether resin, vinyl resin, modified crystalline resin, and the like. These may be used alone or in combination of two or more.

The polyester resin used as the crystalline resin is a crystalline polyester resin (hereinafter sometimes referred to as "crystalline polyester resin C"). The crystalline polyester resin C will be explained below.

Since the crystalline polyester resin C has high crystallinity, it exhibits heat-melting characteristics that exhibit a rapid viscosity change near the fixing start temperature.

By using the crystalline polyester resin C having such characteristics together with the amorphous polyester resin B, resin particles having both good heat-resistant storage stability and low-temperature fixability can be obtained. For example, when used together, the heat-resistant storage property due to crystallinity is good until just before the melting start temperature, but at the melting start temperature, a rapid viscosity decrease (sharp melt property) occurs due to the melting of the crystalline polyester resin C, and as a result, the above-mentioned It is compatible with the amorphous polyester resin B, and the viscosity of both resins decreases rapidly, so that good fixing can be achieved.

(Crystalline polyester resin)
The crystalline polyester resin is obtained from a polyhydric alcohol and a polyhydric carboxylic acid such as a polyhydric carboxylic acid, a polycarboxylic anhydride, a polycarboxylic acid ester, or a derivative thereof.

In addition, as mentioned above, the crystalline polyester resin in this embodiment includes a polyhydric alcohol, a polyhydric carboxylic acid such as a polyhydric carboxylic acid, a polycarboxylic acid anhydride, a polyhydric carboxylic acid ester, or a derivative thereof. Modified polyester resins, such as prepolymers, and resins obtained by subjecting the prepolymers to crosslinking and/or elongation reactions do not belong to the crystalline polyester resins.

((Polyhydric alcohol))
The polyhydric alcohol is not particularly limited and can be appropriately selected depending on the purpose, and includes, for example, diols and trihydric or higher alcohols.

Examples of diols include saturated aliphatic diols. Examples of the saturated aliphatic diol include straight chain saturated aliphatic diols and branched saturated aliphatic diols. Among these, straight chain saturated aliphatic diols are preferred, and straight chain saturated aliphatic diols having 2 to 12 carbon atoms are preferred. Diols are more preferred. If the saturated aliphatic diol is a branched type, the crystallinity of the crystalline polyester resin may decrease and the melting point may decrease. Moreover, when the carbon number of the saturated aliphatic diol exceeds 12, it becomes difficult to obtain a material for practical use.

Examples of the saturated aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1, 8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1, Examples include 18-octadecanediol and 1,14-eicosandecanediol. Among these, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9 -nonanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred.

Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and the like. These may be used alone or in combination of two or more.

((polyhydric carboxylic acid))
The polyvalent carboxylic acid is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include divalent carboxylic acids and trivalent or higher carboxylic acids.

Examples of divalent carboxylic acids include oxalic acid, succinic acid, glutaric acid, adipic acid, superric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 - Saturated aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconine aromatic dicarboxylic acids such as acids; and the like. Further, anhydrides thereof and lower alkyl esters (having 1 to 3 carbon atoms) thereof may also be mentioned. Among these, from the viewpoint of carbon neutrality, saturated aliphatic compounds having 12 or less carbon atoms derived from plants are preferred.

Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and their anhydrides and Examples include lower (1 to 3 carbon atoms) alkyl esters.

These may be used alone or in combination of two or more.

The crystalline polyester resin is preferably composed of a linear saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a linear saturated aliphatic diol having 2 to 12 carbon atoms. As a result, the toner has high crystallinity and excellent sharp melting properties, so it can exhibit excellent low-temperature fixing properties. In addition, as a method for controlling the crystallinity and softening point of crystalline polyester resins, we have added trivalent or higher polyhydric alcohols such as glycerin to the alcohol component during polyester synthesis, and trivalent or higher polyhydric alcohols such as trimellitic anhydride to the acid component. Examples include designing and using a non-linear polyester obtained by adding a carboxylic acid and performing condensation polymerization.

The molecular structure of crystalline polyester resin can be confirmed by X-ray diffraction, GC/MS, LC/MS, IR measurement, etc. in addition to NMR measurement using solutions and solids. Examples include those having absorption based on δ _CH (out-of-plane bending vibration) of an olefin at ±10 cm ⁻¹ or 990 ±10 cm ⁻¹ .

Regarding the molecular weight, those with a sharp molecular weight distribution and low molecular weight have excellent low-temperature fixing properties, and if there are many components with low molecular weight, heat-resistant storage stability will deteriorate. From this point of view, in the molecular weight distribution of the soluble portion of o-dichlorobenzene determined by GPC, the peak position of the molecular weight distribution map with log(M) on the horizontal axis and mass% on the vertical axis is 3.5 to 4.0. range, the half width of the peak is 1.5 or less, the weight average molecular weight (Mw) is 3,000 to 30,000, the number average molecular weight (Mn) is 1,000 to 10,000, and the weight average molecular weight ( The ratio Mw/Mn of Mw) to the number average molecular weight (Mn) is preferably 1 to 10. More preferably, the weight average molecular weight (Mw) is 5,000 to 15,000, the number average molecular weight (Mn) is 2,000 to 10,000, and the Mw/Mn is 1 to 5.

The acid value of the crystalline polyester resin is preferably 5 mgKOH/g or more in order to achieve the desired low-temperature fixability from the viewpoint of affinity between the paper and the resin. For the production of fine particles by phase inversion emulsification, the acid value of the crystalline polyester resin is more preferably 7 mgKOH/g or more. On the other hand, in order to improve hot offset properties, the acid value of the crystalline polyester resin is preferably 45 mgKOH/g or less.

Further, the hydroxyl value of the crystalline polyester resin is preferably 0 to 50 mgKOH/g, more preferably 5 to 50 mgKOH/g, in order to achieve a predetermined low-temperature fixability and good charging characteristics.

[Other ingredients]
The resin particles according to one embodiment may contain other components. Examples of other components include wax, external additives, colorants, charge control agents, cleaning performance improvers, and magnetic materials.

(wax)
The wax is not particularly limited and can be appropriately selected depending on the purpose, but a release agent with a low melting point of 50° C. to 120° C. is preferable. By being dispersed with the resin, the low melting point mold release agent effectively acts as a mold release agent between the interface between the fixing roller and the resin particles, thereby creating an oil-less (oil-like release process for the fixing roller). Good hot offset properties can be obtained even when no molding agent is applied.

Suitable examples of the mold release agent include waxes, waxes, and the like. Waxes and waxes include, for example, vegetable waxes such as carnauba wax, cotton wax, wood wax, and rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin and microcrystalline. Natural waxes such as petroleum waxes such as , and petrolatum; In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax; synthetic waxes such as esters, ketones, and ethers; and the like. Furthermore, fatty acid amides such as 12-hydroxystearamide, stearamide, phthalic anhydride, and chlorinated hydrocarbons; low molecular weight crystalline polymer resins such as poly-n-stearyl methacrylate and poly-n-lauryl; Homopolymers or copolymers of polyacrylate such as methacrylate (for example, n-stearylacrylate-ethyl methacrylate copolymers, etc.); crystalline polymers having long alkyl groups in side chains, etc. may also be used. These may be used alone or in combination of two or more.

From the viewpoint of reducing environmental impact, vegetable waxes are preferred.

The melting point of the wax is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 50°C to 120°C, more preferably 60°C to 90°C. When the melting point is 50° C. or higher, it is possible to prevent the wax from adversely affecting heat-resistant storage stability, and when it is 120° C. or lower, the problem of cold offset occurring during fixing at low temperatures can be effectively prevented. The melt viscosity of the wax is preferably 5 cps to 1,000 cps, more preferably 10 cps to 100 cps, as measured at a temperature 20° C. higher than the melting point of the wax. If the melt viscosity is 5 cps or more, deterioration in mold releasability can be prevented, and if it is 1,000 cps or less, the effects of hot offset resistance and low temperature fixing properties can be sufficiently exhibited. The content of wax in the resin particles is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0% by mass to 40% by mass, more preferably 3% by mass to 30% by mass.

(external additive)
Inorganic fine particles, polymeric fine particles, and the like can be used as external additives.

Inorganic fine particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, silica sand, clay, mica, and wollastonite. , diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, and the like. Among these, silica, alumina, and titanium oxide are preferred.

Further, the inorganic fine particles may be surface-treated with a hydrophobizing agent to increase hydrophobicity and suppress deterioration of flow characteristics and charging characteristics even under high humidity. Examples of hydrophobizing agents include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oil, modified silicone oil, etc. are mentioned as preferred hydrophobizing agents.

Examples of polymeric fine particles include polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, methacrylic ester and acrylic ester copolymers, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins. Examples include polymer particles according to.

Further, the average particle diameter of the primary particles of the inorganic fine particles is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 nm to 2 μm, more preferably 10 nm to 500 nm. When the average particle diameter is 5 nm or more, aggregation of the inorganic fine particles can be suppressed and the inorganic fine particles can be uniformly dispersed in the resin particles. When the average particle diameter is 2 μm or less, heat-resistant storage stability can be improved due to the filler effect.

Note that the average particle diameter is a value obtained by directly determining the particle diameter from a photograph obtained by a transmission electron microscope, and it is preferable to observe at least 100 particles and use the average value of their major diameters.

The specific surface area of the inorganic fine particles measured by the BET method is preferably 20 to 500 m ² /g.

The content of the inorganic fine particles is preferably 0.01% by mass to 5% by mass of the resin particles.

(colorant)
As the colorant, known dyes and pigments can be used, such as carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, loess, Yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R) ), tartrazine lake, quinoline yellow lake, anthrazan yellow BGL, isoindolinone yellow, red red red, lead red, lead vermilion, cadmium red, cadmium mercury red, antimony vermilion, permanent red 4R, para red, physe Red, parachlororthonitroaniline red, Lysole Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Lysol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pogment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazole Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock blue lake, Victoria blue lake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, indanthrene blue (RS, BC), indigo, ultramarine, navy blue, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, Manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green gold, acid green lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide , zinc white, litobone and mixtures thereof can be used.

(Charge control agent)
As the charge control agent, a general charge control agent can be used. Examples of the charge control agent include nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, and alkoxy dyes. Amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus elements or compounds, tungsten elements or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives, etc. . Specifically, Bontron 03 is a nigrosine-based dye, Bontron P-51 is a quaternary ammonium salt, Bontron S-34 is a metal-containing azo dye, E-82 is an oxynaphthoic acid-based metal complex, and E- is a salicylic acid-based metal complex. 84, phenolic condensate E-89 (manufactured by Orient Chemical Industry Co., Ltd.), quaternary ammonium salt molybdenum complexes TP-302 and TP-415 (manufactured by Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, boron complex LR-147 (manufactured by Nippon Carlit Co., Ltd.), copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymeric compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts. The charge control agent may be used in an amount within a range that exhibits performance and does not interfere with fixing properties, etc., and is 0.5% to 5% by mass, preferably 0.8% to 3% by mass in the resin particles. Good to be included.

(Cleanability improver)
The cleaning performance improver is not particularly limited as long as it is added to the resin particles in order to remove the developer remaining on the photoreceptor or primary transfer medium after transfer, and it can be selected as appropriate depending on the purpose. can. Examples of the cleaning performance improver include zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, polymer particles produced by soap-free emulsion polymerization such as polymethyl methacrylate particles, and polystyrene particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and preferably have a volume average particle diameter of 0.01 μm to 1 μm.

(Magnetic material)
The magnetic material is not particularly limited and can be appropriately selected from known materials depending on the purpose, such as iron powder, magnetite, ferrite, etc. Among these, white ones are preferred in terms of color tone.

<Characteristics of resin particles>
[Particle diameter of resin particles]
The particle diameter of the resin particles according to one embodiment is measured using Coulter Multisizer III (manufactured by Coulter Inc.). The particle diameter of the resin particles is determined as follows. First, 2 mL of a surfactant (sodium dodecylbenzenesulfonate, manufactured by Tokyo Kasei Co., Ltd.) is added as a dispersant to 100 mL of the electrolytic solution. The electrolytic solution is an approximately 1% NaCl aqueous solution prepared using primary sodium chloride, and ISOTON-II (manufactured by Coulter) can be used. A solid content of 10 mg of the sample to be measured is further added to a mixture of electrolyte and surfactant to obtain an electrolyte in which the sample is suspended. The electrolytic solution in which the sample was suspended was dispersed for about 1 to 3 minutes using an ultrasonic disperser, and the volume and number of resin particles were measured using a Coulter Multisizer III using a 100 μm aperture. Calculate distribution and number distribution. From the obtained distribution, the volume average particle diameter (Dv) of the resin particles is determined.

[Method for measuring melting point and glass transition temperature (Tg)]
The melting point and glass transition temperature (Tg) of the resin particles according to one embodiment can be measured using, for example, a DSC system (differential scanning calorimeter) (“Q-200”, manufactured by TA Instruments). . Specifically, the melting point and glass transition temperature of the target sample can be measured by the following procedure. First, about 5.0 mg of a target sample is placed in an aluminum sample container, and the sample container is placed on a holder unit and set in an electric furnace. Next, under a nitrogen atmosphere, it is heated from -80°C to 150°C at a temperature increase rate of 10°C/min (first temperature increase). Thereafter, it is cooled from 150° C. to −80° C. at a temperature decreasing rate of 10° C./min, and further heated to 150° C. at a temperature increasing rate of 10° C./min (second temperature raising). During each of the first and second temperature increases, a DSC curve is measured using a differential scanning calorimeter ("Q-200", manufactured by TA Instruments). From the obtained DSC curve, the DSC curve at the first temperature increase can be selected using the analysis program in the Q-200 system, and the glass transition temperature (Tg) of the target sample at the first temperature increase can be determined. . Similarly, by selecting the DSC curve during the second temperature rise, the glass transition temperature (Tg) of the target sample during the second temperature rise can be determined.

Also, from the obtained DSC curve, use the analysis program in the Q-200 system to select the DSC curve at the first temperature increase, and determine the endothermic peak top temperature at the first temperature increase of the target sample as the melting point. I can do it. Similarly, by selecting the DSC curve during the second temperature rise, the endothermic peak top temperature of the target sample during the second temperature rise can be determined as the melting point.

In addition, in this specification, the glass transition temperature (Tg) and melting point of the amorphous polyester resin A, the amorphous polyester resin B, the crystalline polyester resin C, and other constituent components such as a mold release agent are particularly described. Unless otherwise specified, the endothermic peak top temperature and glass transition temperature (Tg) during the second temperature rise are taken as the melting point and glass transition temperature (Tg) of each target sample.

[Average particle diameter, average circularity]
For example, a flow type particle image analyzer (FPIA-3000, manufactured by Sysmex Corporation) can be used to measure the average particle diameter and average circularity. A specific measurement method is to add 0.1 ml to 0.5 ml of a surfactant as a dispersant, preferably an alkylbenzene sulfonate, to 100 ml to 150 ml of water from which impure solids have been removed in advance in a container, and then add the measurement sample. Add about 0.1g to 0.5g of. The suspension containing the sample is dispersed for about 1 to 3 minutes using an ultrasonic disperser, and the average particle size is determined using a flow-type particle image analyzer at a dispersion concentration of 3000 particles/μl to 10,000 particles/μl. and measure the average circularity. However, the particle diameter is determined by the equivalent circle diameter, and the average particle diameter is determined by the equivalent circle diameter (number based). The analysis conditions of the flow type particle image analyzer are as follows.
・Particle size limitation: 0.5μm≦circle-equivalent diameter (number of particles)≦200.0μm
・Particle shape limitation: 0.93<circularity≦1.00
Note that the average circularity is defined as follows.
(Average circularity) = (perimeter of a circle equal to the projected area) / (perimeter of the projected image)

[Measurement of molecular weight]
The molecular weight of each component of the resin particles can be measured, for example, by the following method.
・Gel permeation chromatography (GPC) measuring device: GPC-8220GPC (manufactured by Tosoh Corporation)
・Column: TSKgel SuperHZM-H 15cm 3 rows (manufactured by Tosoh Corporation)
・Temperature: 40℃
・Solvent: THF
・Flow rate: 0.35mL/min
・Sample: Inject 100 μL of 0.15% by mass sample ・Sample pretreatment: After dissolving resin particles at 0.15% by mass in tetrahydrofuran THF (containing stabilizer, manufactured by Wako Pure Chemical Industries, Ltd.), it was filtered with a 0.2 μm filter. Filter and use the filtrate as a sample. Inject 100 μL of the THF sample solution and perform measurement.

When measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithm value and the count number of a calibration curve prepared using several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for creating a calibration curve, ShowdexSTANDARD Std. No. S-7300, S-210, S-390, S-875, S-1980, S-10.9, S-629, S-3.0, S-0.580 are used. An RI (refractive index) detector is used as a detector.

<Method for manufacturing resin particles>
A method for manufacturing resin particles according to one embodiment will be described. The method for producing resin particles according to one embodiment includes an oil phase production process, an aqueous phase production process, a phase inversion emulsification process, a solvent removal process, an aggregation process, and a fusion process, and further includes a shelling process, as necessary. It includes other processes such as a cleaning process, a drying process, an annealing process, and an external addition process.

(Oil phase preparation process)
In the oil phase preparation step, first, in an organic solvent, resin (amorphous resin, non-crystalline resin, crystalline resin, etc.), which is a raw material for the resin particles, and PET or PBT, and if necessary, The oil phase is prepared by dissolving or dispersing materials such as a colorant, prepolymer (precursor of amorphous polyester resin A), and wax. In addition, a part of the said material may be added in the aggregation process mentioned later.

The method for preparing the oil phase is not particularly limited and can be selected as appropriate depending on the purpose. For example, a method of gradually adding raw materials such as a resin to an organic solvent with stirring and dissolving or dispersing it. etc.

For dispersion, a known dispersion machine can be used, for example, a dispersion machine such as a bead mill or a disc mill can be used.

As each raw material used in the oil phase preparation step, those explained in the section of <Resin particles> above can be used. These may be used alone or in combination of two or more. It is preferable that at least one of the resins (amorphous resin, amorphous resin, and crystalline resin) is a biomass-derived resin.

The organic solvent is not particularly limited and can be appropriately selected depending on the purpose, but a volatile solvent with a boiling point of less than 100° C. is preferred from the standpoint of facilitating subsequent removal of the organic solvent.

Examples of such organic solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, Mention may be made of ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol and isopropyl alcohol. These may be used alone or in combination of two or more.

When the resin to be dissolved or dispersed in an organic solvent is a resin having a polyester skeleton, the organic solvent may be an ester solvent such as methyl acetate, ethyl acetate, butyl acetate, or a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone. , preferred in terms of high solubility. Among these, as the organic solvent, methyl acetate, ethyl acetate, or methyl ethyl ketone is preferable because of its high solvent removability.

The amount of the organic solvent to be used is not particularly limited and can be selected appropriately depending on the purpose, but it is preferably 40 parts by mass to 300 parts by mass, and 60 parts by mass to 140 parts by mass, based on 100 parts by mass of the raw material for the resin particles. Parts by weight are more preferable, and even more preferably 80 parts by weight to 120 parts by weight.

(Aqueous phase preparation process)
In the aqueous phase preparation step, an aqueous phase (aqueous medium) is prepared.

The aqueous medium is not particularly limited and can be appropriately selected from known ones, including water, water-miscible solvents, and mixtures thereof. From the viewpoint of granulation properties, the concentration of the water-miscible solvent is preferably equal to or lower than the saturation concentration of the ion-exchanged water used in the phase inversion emulsification step.

The water-miscible solvent is not particularly limited and can be appropriately selected from known solvents, such as alcohol, dimethylformamide, tetrahydrofuran, cellosolves, lower ketones, and esters.

Examples of the alcohol include methanol, isopropanol, and ethylene glycol.

Examples of lower ketones include acetone and methyl ethyl ketone.

Examples of esters include ethyl acetate.

These may be used alone or in combination of two or more.

(Phase inversion emulsification process)
In the phase inversion emulsification step, the oil phase obtained in the oil phase preparation step is made into fine particles.

After neutralizing the oil phase, ion-exchanged water is added to the neutralized oil phase, and a fine particle dispersion is obtained by phase inversion emulsification in which a water-in-oil dispersion is inverted to an oil-in-water dispersion.

Phase inversion emulsification is performed by stirring.

This is done while uniformly mixing and dispersing using an ordinary stirrer or dispersion device.

There are no particular restrictions on the stirring blade, and it can be appropriately selected depending on the viscosity of the solution. Examples include low-viscosity stirring impellers such as paddles and propellers, medium-viscosity stirring impellers such as anchors and Maxblend, and high-viscosity stirring impellers such as helical ribbons.

Dispersion equipment is not particularly limited, and includes ultrasonic dispersion machines, bead mills, ball mills, roll mills, homomixers, ultra mixers, disper mixers, penetrating high pressure dispersion equipment, collision type high pressure dispersion equipment, porous high pressure dispersion equipment, and ultrahigh pressure dispersion equipment. Examples include a homogenizer and an ultrasonic homogenizer. A conventional stirrer and dispersion device may be used in combination.

Among these, paddles and anchors are preferred in that the volume average particle size of the dispersion (oil droplets) can be controlled within the preferred range.

As the base for neutralizing the oil phase, either a basic inorganic compound or a basic organic compound may be used. Examples of the basic inorganic compound include sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonia, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, ammonia, and the like. Basic organic compounds include N,N-dimethylethanolamine, N,N-diethylethanolamine, triethanolamine, tripropanolamine, tributanolamine, triethylamine, n-propylamine, n-butylamine, isopropylamine, mono Examples include methanolamine, morpholine, methoxypropylamine, pyridine, vinylpyridine, isophoronediamine, and the like.

When a stirring blade is used, there are no particular restrictions on the conditions such as rotation speed, stirring time, stirring temperature, etc., and they can be appropriately selected depending on the purpose.

The rotation speed is not particularly limited, and is preferably 1,00 rpm to 1,000 rpm, more preferably 200 rpm to 600 rpm.

The stirring time and stirring temperature are not particularly limited and may be appropriately selected depending on the purpose.

Further, a dispersant may be used if necessary. The dispersant is not particularly limited and can be appropriately selected depending on the purpose, and examples include surfactants, poorly water-soluble inorganic compound dispersants, and polymeric protective colloids. These may be used alone or in combination of two or more. Among these, surfactants are preferred.

The surfactant is not particularly limited and can be appropriately selected depending on the purpose; for example, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc. may be used. Can be done.

The anionic surfactant is not particularly limited and can be appropriately selected depending on the purpose, and includes, for example, alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, and the like. Among these, those having a fluoroalkyl group are preferred.

(Desolvation step)
In the solvent removal step, the organic solvent is removed from the obtained fine particle dispersion.

In order to remove the organic solvent from the obtained fine particle dispersion, a method can be adopted in which the temperature of the entire system is gradually raised while stirring, and the organic solvent in the droplets is completely evaporated and removed.

Alternatively, the organic solvent in the droplets can be completely removed by spraying the resulting fine particle dispersion into a dry atmosphere while stirring. Furthermore, the organic solvent may be removed by evaporation by reducing the pressure while stirring the fine particle dispersion. Alternatively, the organic solvent may be removed by evaporation by spraying gas while stirring the fine particle dispersion.

These means may be used alone or in combination.

The drying atmosphere in which the fine particle dispersion is sprayed is generally a heated gas such as air, nitrogen, carbon dioxide, combustion gas, etc., and in particular, various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling point solvent used. A spray dryer, belt dryer, rotary kiln, etc. can be used in a short time to achieve the desired quality.

By removing the organic solvent from the fine particle dispersion obtained by the above method, a fine particle dispersion can be obtained.

(Agglomeration process)
In the aggregation step, the resulting fine particle dispersion is agglomerated while stirring until it reaches a desired particle size to obtain agglomerated particles.

For flocculation, existing methods such as adding a flocculant and adjusting pH can be used. When adding a flocculant, it may be added as is, but it is preferable to use an aqueous solution of the flocculant because it can avoid local increases in concentration. Further, it is preferable to add the flocculant gradually while checking the particle size of the fine particles.

The temperature of the dispersion during aggregation is preferably around the glass transition temperature Tg of the resin used. If the temperature of the fine particle dispersion liquid is too low, aggregation will not proceed much, resulting in poor efficiency. If the temperature of the fine particle dispersion liquid is too high, the aggregation rate will increase, coarse particles will be generated, and the particle size distribution will deteriorate.

Once the target particle size is reached, agglomeration is stopped. Methods for stopping aggregation include adding a salt or chelating agent with a low ionic valence, adjusting the pH, lowering the temperature of the dispersion, and diluting the concentration by adding a large amount of an aqueous medium. can be used.

By the above method, a dispersion of resin particles can be obtained.

In the aggregation step, a colorant, a crystalline resin, and a mold release agent may be added. In that case, by mixing the material with a dispersion liquid in an aqueous medium or the above-mentioned fine particle dispersion liquid and then agglomerating it, agglomerated particles in which the colorant, crystalline resin, and mold release agent are uniformly dispersed can be obtained. be able to.

In this embodiment, it is preferable to use a metal salt of Na having a low ionic valence. By replacing Na with the metal used as a flocculant, aggregation can be efficiently stopped.

((flocculant))
As the flocculant, a general flocculant can be used. The flocculants may be used alone or in combination of two or more.

The metal ion functions as a crosslinking agent that crosslinks the ends of the resin.

For example, metal salts of monovalent metals such as sodium and potassium, metal salts of divalent metals such as calcium and magnesium, metal salts of trivalent metals such as iron and aluminum, etc. can be used.

In this embodiment, divalent metal salts are preferred in order to obtain resin particles with a good particle size distribution.

When monovalent, the crosslinking effect is low. In addition, when using a biobath resin, an amorphous resin with many aromatic ring skeletons, and a PET or PBT resin, if a trivalent or higher valent metal salt with a large structural difference and a fast crosslinking reaction rate is used, The particle size distribution of the resin particles becomes poor. Among the divalent metals, the cohesiveness of Mg was particularly good. If the metal used as a flocculant or the like remains in the resin particles, it will deteriorate the charging property, so the amount of divalent metal elements in the resin particles is set to 0.05% by mass to 1% by mass. When the amount of elements in the resin particles is 0.05% by mass or more, the amount of metal used during aggregation is sufficient and the cohesive force is sufficient, so that deterioration of particle size distribution can be suppressed. If the amount of elements in the resin particles is 1% by mass or less, the particles can have chargeability. The type and amount of metal in the resin particles can be adjusted by the type and amount of the flocculant and stopper, and the cleaning conditions in the cleaning step.

(fusion process)
In the fusing step, the obtained agglomerated particles are fused by heat treatment to reduce irregularities and to make them spherical. Fusion may be achieved by heating the dispersion of aggregated particles while stirring. The temperature of the liquid is preferably around a temperature exceeding the glass transition temperature Tg of the resin used.

(shelling process)
Further, shelling may be performed as necessary (shelling step). In the shelling step, a shell layer is formed on the spherical particles obtained in the fusion step.

The method for forming the shell layer is not particularly limited and can be appropriately selected depending on the purpose. As a method for forming the shell layer, for example, after producing spherical particles with the desired particle size in the fusion process, adding an amorphous resin and repeating the aggregation process and the fusion process, the shell layer is formed. Examples include a method of forming a layer.

(Washing/drying process)
In the washing/drying step, only the resin particles are taken out from the resin particle dispersion obtained by the above method, washed, and dried.

Since the resin particle dispersion obtained by the above method contains auxiliary materials such as aggregation salts in addition to the resin particles, washing is performed to remove only the resin particles from the dispersion. Methods for cleaning the resin particles include, but are not particularly limited to, centrifugation, vacuum filtration, and filter press methods. A cake of resin particles can be obtained by any of the methods, but if the cake cannot be washed sufficiently in one operation, the cake obtained is dispersed in an aqueous solvent again to form a slurry, and then the resin particles can be prepared by any of the methods described above. The process of taking out the cake may be repeated, or if cleaning is carried out by vacuum filtration or filter press, an aqueous solvent may be passed through the cake to wash away the sub-materials entrapped by the colored resin particles. . The aqueous solvent used for this cleaning is water or a mixed solvent of water and an alcohol such as methanol or ethanol, but water is preferably used from the viewpoint of cost and environmental burden due to wastewater treatment.

Since the washed resin particles contain a large amount of aqueous medium, only the resin particles can be obtained by drying and removing the aqueous medium.

As a drying method, use dryers such as a spray dryer, vacuum freeze dryer, vacuum dryer, stationary shelf dryer, mobile shelf dryer, fluidized bath dryer, rotary dryer, stirring dryer, etc. be able to. The dried resin particles are preferably dried until the moisture content is finally less than 1%. In addition, if the colored resin particles after drying are soft and agglomerated, and if there is any inconvenience during use, use equipment such as a jet mill, Henschel mixer, super mixer, coffee mill, Ooster blender, food processor, etc. to dissolve the particles. Crushing may be performed to loosen soft agglomerations.

(Annealing process)
In the annealing step, when a crystalline resin is added, by performing an annealing treatment after drying, the amorphous resin and the crystalline resin undergo phase separation, thereby improving fixing properties. Specifically, it may be stored at a temperature around the glass transition temperature Tg for 10 hours or more.

(External addition process)
In order to give the obtained resin particles fluidity, chargeability, cleanability, etc., other components such as wax, external additives, colorants, charge control agents, and cleanability improvers are added. You can also mix it.

Specific mixing methods include applying impact force to the mixture using blades rotating at high speed, or introducing the mixture into a high-speed airflow, accelerating it, and colliding the particles or composite particles against a suitable collision plate. etc.

The equipment includes an Ong Mill (manufactured by Hosokawa Micron), a modified I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) to lower the crushing air pressure, a hybridization system (manufactured by Nara Kikai Seisakusho Co., Ltd.), and a Cryptron. System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.

As described above, the resin particles according to one embodiment contain PET or PBT, have a radiocarbon isotope ^14C concentration of 10.8 pMC or more, and contain divalent metal elements excluding external additives. Contains 0.05% to 1% by mass. The resin particles according to one embodiment include PET or PBT, so that even if a biomass-derived resin is included instead of a petroleum-derived resin, the structural difference of the biomass-derived resin can be improved while improving environmental friendliness. It is possible to reduce the impact on In addition, the resin particles according to one embodiment include 0.05% to 1% by mass of a divalent metal element, so that when the resin particles are aggregated using a metal salt during the production of the resin particles, the resin particles can be bonded together. can be aggregated mildly, making it possible to obtain resin particles with a good particle size distribution.

Therefore, the resin particles according to one embodiment can reduce environmental impact, have an excellent particle size distribution, and form an image with excellent image quality.

The resin particles according to one embodiment include at least one of an amorphous resin, an amorphous resin, and a crystalline resin, and at least one of the amorphous resin, the amorphous resin, and the crystalline resin. It contains a biomass-derived resin, and the total content of the biomass-derived resin and PET or PBT can be 50% by mass or more based on the total mass of the resin particles. As a result, the resin particles according to one embodiment include a biomass-derived resin and increase environmental friendliness, and also reliably reduce the influence on the properties of the resin particles due to the structural difference between the biomass-derived resin and the petroleum-derived resin. be able to. Therefore, the resin particles according to one embodiment can improve the particle size distribution and more stably provide images with excellent quality while reducing environmental load.

The resin particles according to one embodiment can contain more PET or PBT than the biomass-derived resin. Thereby, the resin particles according to one embodiment can further reduce the influence on the properties of the resin particles due to the structural difference between the biomass-derived resin and the petroleum-derived resin.

The resin particles according to one embodiment may contain 0.1% by mass to 0.5% by mass of magnesium among the divalent metal elements. As a result, when the resin particles according to one embodiment are agglomerated using a metal salt during the production of the resin particles, the resin particles can be more reliably agglomerated more mildly, so that the particle size distribution is even better. It is possible to reliably obtain resin particles with high quality.

The resin particles according to one embodiment contain sodium, contain more magnesium than sodium among divalent metal elements, and can have a sodium content of more than 0.05% by mass. As a result, when the resin particles according to one embodiment are agglomerated using a metal salt during the production of the resin particles, the aggregation of the resin particles can be performed more mildly, so that the particle size distribution is even better. Resin particles can be reliably obtained.

Since the resin particles according to one embodiment have the above characteristics, they can be effectively used as image forming materials for toners, developers, toner sets, toner storage units, image forming apparatuses, and the like.

<Toner>
The toner according to one embodiment includes the resin particles according to one embodiment, and may be made of the resin particles according to one embodiment.

By using the resin particles according to one embodiment in a toner, the environmental burden can be suppressed, and even if a plant-derived resin is used, it is possible to provide an image with excellent low-temperature fixing properties and charging properties, and excellent image quality. .

<Developer>
The developer according to one embodiment includes the toner according to one embodiment, and can contain other appropriately selected components such as a carrier as necessary. Thereby, it is possible to stably form a high-quality image with excellent transferability, charging performance, etc.

The developer may be a one-component developer or a two-component developer, but when used in high-speed printers that support the recent improvement in information processing speed, it is important to improve the lifespan. Therefore, a two-component developer is preferable.

When the toner according to one embodiment is used as a one-component developer, there is little variation in the particle size of the toner even when the toner is accounted for, and the toner is not easily filmed onto the developing roller or by a blade that thins the toner. The fusion of toner to the members is suppressed to a minimum, and high-quality images can be obtained in the developing device.

When the developer according to one embodiment is used as a two-component developer, it can be mixed with a carrier and used as the developer. When the toner according to one embodiment is used as a two-component developer, there is little variation in the toner particle size even after long-term toner balance, and good and stable developability is achieved even during long-term agitation in a developing device. and images are obtained.

The content of the carrier in the two-component developer can be appropriately selected depending on the purpose, but it is preferably 90 parts by mass to 98 parts by mass, and 93 parts by mass to 97 parts by mass, based on 100 parts by mass of the two-component developer. Parts by mass are more preferred.

The developer according to one embodiment can be suitably used for image formation by various known electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method.

[Career]
The carrier is not particularly limited and can be appropriately selected depending on the purpose, but preferably has a core material and a resin layer (covering layer) covering the core material.

(core material)
The material of the core material is not particularly limited and can be selected as appropriate depending on the purpose, for example, a manganese-strontium material with a content of 50 emu/g to 90 emu/g, a manganese-magnesium material with a content of 50 emu/g to 90 emu/g. Examples include materials. Further, in order to ensure image density, it is preferable to use a highly magnetized material such as iron powder of 100 emu/g or more and magnetite of 75 emu/g to 120 emu/g. In addition, it is recommended to use a low magnetization material such as a copper-zinc type material with a strength of 30 emu/g to 80 emu/g because it can reduce the impact of the developer in a spiked state on the photoconductor and is advantageous for improving image quality. is preferred. These may be used alone or in combination of two or more.

The volume average particle diameter of the core material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 μm to 150 μm, more preferably 40 μm to 100 μm. If the volume average particle diameter is 10 μm or more, it is possible to effectively prevent the problem that the carrier contains a large amount of fine powder, and the magnetization per particle decreases, causing the carrier to scatter. On the other hand, if it is less than 150 μm, the specific surface area decreases and toner scattering may occur, and in full color with many solid areas, it is not possible to effectively prevent the problem of poor reproduction of solid areas. can.

(resin layer)
The resin layer can contain a resin and other components as necessary. As the resin used for the resin layer, known materials that can provide the necessary chargeability can be used. Specifically, it is preferable to use a silicone resin, an acrylic resin, or a combination thereof. Moreover, it is preferable that the composition for forming the resin layer contains a silane coupling agent.

The average thickness of the resin layer is preferably 0.05 to 0.50 μm.

<Developer storage container>
A developer storage container according to one embodiment stores a developer according to one embodiment. The developer storage container is not particularly limited and can be appropriately selected from known containers, including one having a container body and a cap.

In addition, the size, shape, structure, material, etc. of the container body are not particularly limited, but the shape is preferably cylindrical, etc., and spiral irregularities are formed on the inner peripheral surface, and by rotating it, It is particularly preferable that a part or all of the spiral irregularities have a bellows function so that the developer content can migrate to the discharge port side. Further, the material is not particularly limited, but preferably has good dimensional accuracy, such as polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, Examples include resin materials such as polyacetal resin.

The developer storage container is easy to store, transport, etc. and has excellent handling properties, so it can be removably attached to an image forming apparatus, a process cartridge, etc., which will be described later, and used for replenishing developer.

<Toner storage unit>
The toner storage unit according to one embodiment can store the toner according to one embodiment. The toner storage unit according to one embodiment refers to a unit that has a function of storing toner and stores toner therein. Here, examples of the toner storage unit include a toner storage container, a developing device, and a process cartridge.

The toner storage container refers to a container that stores toner.

A developing device has means for storing and developing toner.

A process cartridge is a cartridge that integrates at least an electrostatic latent image carrier (also referred to as an image carrier) and a developing means, stores toner, and is removably attached to an image forming apparatus. The process cartridge may further include at least one selected from charging means, exposure means, cleaning means, and the like.

The toner storage unit according to one embodiment accommodates the toner according to one embodiment. By attaching the toner storage unit according to one embodiment to an image forming apparatus and forming an image, the image formation is performed using the toner according to one embodiment, so it has excellent low-temperature fixability and charging property, and has high image quality. You can get toner with high price.

<Image forming device>
An image forming apparatus according to one embodiment includes: an electrostatic latent image carrier; an electrostatic latent image forming section that forms an electrostatic latent image on the electrostatic latent image carrier; It has a developing section that develops the formed electrostatic latent image using toner to form a toner image, and may further have other configurations as necessary.

The image forming apparatus according to one embodiment more preferably includes, in addition to the electrostatic latent image carrier, the electrostatic latent image forming section, and the developing section described above, a transfer section that transfers the toner image to a recording medium. and a fixing section that fixes the transferred image transferred to the surface of the recording medium.

In the developing section, a toner according to an embodiment is used. Preferably, a toner image may be formed by using a developer containing the toner according to one embodiment and further containing other components such as a carrier as necessary.

(Electrostatic latent image carrier)
The material, shape, structure, size, etc. of the electrostatic latent image carrier (sometimes referred to as "electrophotographic photoreceptor" or "photoreceptor") are not particularly limited, and are appropriately selected from known ones. be able to. Examples of the material of the electrostatic latent image carrier include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors (OPC) such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferable in terms of long life, and organic photoconductor (OPC) is preferable in terms of obtaining higher definition images.

As an amorphous silicon photoreceptor, for example, a support is heated to 50° C. to 400° C., and a vacuum evaporation method, a sputtering method, an ion plating method, a thermal CVD (Chemical Vapor Deposition) method is applied to the support. A photoreceptor having a photoconductive layer made of a-Si can be used by a film forming method such as photo-CVD, plasma CVD, or the like. Among these, the plasma CVD method, ie, a method in which a raw material gas is decomposed by direct current, high frequency, or microwave glow discharge to form an a-Si deposited film on a support, is preferred.

The shape of the electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but a cylindrical shape is preferred. The outer diameter of the cylindrical electrostatic latent image carrier is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 3 mm to 100 mm, more preferably 5 mm to 50 mm, particularly 10 mm to 30 mm. preferable.

(Electrostatic latent image forming section)
The electrostatic latent image forming section is not particularly limited as long as it is a means for forming an electrostatic latent image on an electrostatic latent image carrier, and can be appropriately selected depending on the purpose. The electrostatic latent image forming section includes, for example, a charging member (charger) that uniformly charges the surface of the electrostatic latent image carrier, and an exposure member that imagewise exposes the surface of the electrostatic latent image carrier. (exposure device).

The charger is not particularly limited and can be selected as appropriate depending on the purpose, but for example, a contact charger equipped with a conductive or semiconductive roll, brush, film, rubber blade, etc., a corotron, a scorotron. Examples include non-contact chargers that utilize corona discharge.

The charger may have any shape other than a roller, such as a magnetic brush or a fur brush, and can be selected according to the specifications and form of the image forming apparatus.

The charger is preferably one that is disposed in contact with or in a non-contact state with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by applying DC and AC voltages in a superimposed manner. In addition, the charger is a charging roller that is disposed close to the electrostatic latent image carrier through a gap tape in a non-contact manner, and the surface of the electrostatic latent image carrier is It is preferable to use one that charges .

Although the charger is not limited to a contact type charger, it is preferable to use a contact type charging member since an image forming apparatus in which ozone generated from the charger is reduced can be obtained.

The exposure device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charger in the form of the image to be formed, and can be selected as appropriate depending on the purpose. Examples include various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system.

The light source used in the exposure device is not particularly limited and can be selected as appropriate depending on the purpose. For example, fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers ( LD), electroluminescence (EL), and other light-emitting materials.

Moreover, various filters such as a sharp cut filter, a band pass filter, a near-infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can also be used in order to irradiate only light in a desired wavelength range.

Note that the exposure device may employ a back-light method in which imagewise exposure is performed from the back side of the electrostatic latent image carrier.

(Developing section)
The developing section is not particularly limited as long as it can develop the electrostatic latent image formed on the electrostatic latent image carrier to form a visible image, and can be appropriately selected depending on the purpose. The developing section may preferably include a developing device that accommodates toner and can apply the toner to the electrostatic latent image in a contact or non-contact manner, such as a developing device equipped with a container containing toner. preferable.

The developer may be a monochrome developer or a multicolor developer. As a developing device, for example, a developer carrier (a rotatable developer carrier) that has a stirrer that frictionally stirs toner to charge the toner and a magnetic field generating section fixed therein, and that carries a developer containing toner on its surface. For example, a developing device having a magnetic roller) is preferably used.

(Transfer section)
The transfer section may include a primary transfer section that transfers a visible image onto an intermediate transfer body to form a composite transfer image, and a secondary transfer section that transfers the composite transfer image onto a recording medium. preferable. Note that the intermediate transfer body is not particularly limited and can be appropriately selected from known transfer bodies depending on the purpose, and suitable examples include a transfer belt and the like.

The transfer section (the primary transfer means and the secondary transfer section) has at least a transfer device for peeling and charging the visible image formed on the electrostatic latent image carrier (photoreceptor) toward the recording medium. preferable. The number of transfer parts may be one, or two or more.

Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, an adhesive transfer device, and the like.

The recording medium is typically plain paper, but there is no particular restriction as long as it can transfer the unfixed image after development, and any known recording medium (recording paper) can be used depending on the purpose. It can be selected as appropriate, and a PET base for OHP or the like can also be used.

(Fusing part)
The fixing section is not particularly limited and can be appropriately selected depending on the purpose, but a known heating and pressing section is suitable. Examples of the heating and pressing section include a combination of a heating roller and a pressure roller, a combination of a heating roller, a pressure roller, and an endless belt, and the like.

The fixing unit includes a heating element including a heating element, a film in contact with the heating element, and a pressure member in pressure contact with the heating element via the film, and the unfixed image is held between the film and the pressure member. Preferably, it is a heating and pressing unit that can heat and fix the formed recording medium by passing it therethrough.

The heating in the heating and pressurizing section is usually preferably performed at a temperature of 80°C to 200°C.

The surface pressure in the heating and pressing section is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably 10 N/cm ² to 80 N/cm ² .

Note that in this embodiment, for example, a known optical fixing device may be used together with or in place of the fixing section depending on the purpose.

(others)
The image forming apparatus according to the primary form may further include, for example, a static elimination section, a recycling section, a control section, and the like.

((static eliminator))
The static eliminator is not particularly limited as long as it can apply a static eliminator bias to the electrostatic latent image carrier, and can be appropriately selected from known static eliminators. For example, a static eliminator is preferably used. Can be mentioned.

((Cleaning Department))
The cleaning section only needs to be capable of removing toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners. Examples of the cleaning unit include a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, a brush cleaner, and a web cleaner.

The image forming apparatus according to the primary form can improve cleaning performance by having the cleaning section. That is, by controlling the adhesion force between toners, the fluidity of the toner can be controlled and the cleaning performance can be improved. Furthermore, by controlling the characteristics of toner after deterioration, it is possible to extend the service life and maintain excellent cleaning quality even under harsh conditions such as high temperature and humidity. Furthermore, since the external additive can be sufficiently released from the toner on the photoreceptor, high cleaning performance can be achieved by forming a deposited layer (dam layer) of the external additive at the cleaning blade nip. can.

((Recycling Department))
The recycling section is not particularly limited, and includes known transport means and the like.

((control unit))
The control section can control the movement of each section mentioned above. The control section is not particularly limited as long as it can control the movements of each of the above sections, and can be appropriately selected depending on the purpose, and includes, for example, control devices such as a sequencer and a computer.

Since the image forming apparatus according to one embodiment can form an image using the toner according to one embodiment, it is possible to reduce power consumption and stably provide high-quality images. .

<Image forming method>
An image forming method according to an embodiment includes an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier, and developing the electrostatic latent image using toner to form a toner image. In addition, other steps may be included as necessary. The image forming method can be preferably performed by the image forming apparatus, the electrostatic latent image forming step can be suitably performed by the electrostatic latent image forming section, and the developing step can be suitably carried out by the developing section. The other steps can be suitably carried out by the other section.

Further, the image forming method according to one embodiment more preferably includes, in addition to the electrostatic latent image forming step and the developing step, a transfer step of transferring the toner image to a recording medium, and a surface of the recording medium. and a fixing step of fixing the transferred image.

In the developing process, a toner according to one embodiment is used. Preferably, a toner image may be formed by using a developer containing the toner according to one embodiment and further containing other components such as a carrier as necessary.

The electrostatic latent image forming step is a step of forming an electrostatic latent image on an electrostatic latent image carrier, and includes a charging step of charging the surface of the electrostatic latent image carrier, and a charging step of charging the surface of the electrostatic latent image carrier. and an exposure step of exposing the surface to light to form an electrostatic latent image. Charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using a charger. Exposure can be performed, for example, by imagewise exposing the surface of the electrostatic latent image carrier using the exposure device. Formation of an electrostatic latent image can be performed, for example, by uniformly charging the surface of an electrostatic latent image carrier and then exposing it imagewise, and can be performed by an electrostatic latent image forming section. .

The developing step is a step of sequentially developing the electrostatic latent image with toners of multiple colors to form a visible image. Formation of a visible image can be performed, for example, by developing an electrostatic latent image using the toner, and can be performed using a developing device.

In the developing device, for example, toner and carrier are mixed and stirred, and the toner is charged by friction at that time and held in a spiked state on the surface of a rotating magnet roller, thereby forming a magnetic brush. Since the magnet roller is placed near the electrostatic latent image carrier (photoreceptor), some of the toner that makes up the magnetic brush formed on the surface of the magnet roller is absorbed by the electrostatic latent image due to the electrical attraction force. Move to the surface of the image carrier (photoreceptor). As a result, the electrostatic latent image is developed with the toner, and a visible image is formed with the toner on the surface of the electrostatic latent image carrier (photoreceptor).

The transfer process is a process of transferring a visible image to a recording medium. In the transfer step, it is preferable that an intermediate transfer member is used, and after the visible image is primarily transferred onto the intermediate transfer member, the visible image is secondarily transferred onto the recording medium. The transfer process includes a primary transfer process in which a visible image is transferred onto an intermediate transfer body to form a composite transferred image using toner of two or more colors, preferably full-color toner, and a primary transfer process in which a composite transferred image is transferred onto a recording medium. An embodiment including a second transfer step of transferring is more preferable. Transfer can be performed, for example, by charging an electrostatic latent image carrier (photosensitive member) with a visible image using a transfer charger, and can be performed by a transfer section.

The fixing process is a process of fixing the visible image transferred to the recording medium using a fixing device, and may be performed each time the visible image is transferred to the recording medium for each color developer, or it may be performed for each color developer. This may be done simultaneously in a stacked state.

The image forming method according to the primary form can further include other steps appropriately selected as necessary, such as a static elimination step, a cleaning step, a recycling step, and the like.

The static elimination step is a process of applying a static elimination bias to the electrostatic latent image carrier to eliminate static electricity, and can be suitably performed by a static elimination unit.

The cleaning step is a step of removing the toner remaining on the electrostatic latent image carrier, and can be suitably carried out by a cleaning section.

The recycling step is a step in which the toner removed in the cleaning step is recycled to the developing section, and can be suitably carried out by the recycling section.

Since the image forming method according to one embodiment can perform image formation using the toner according to one embodiment, it is possible to suppress power consumption and to stably provide high-quality images. .

[One aspect of image forming apparatus]
Next, one aspect of an image forming apparatus according to an embodiment will be described with reference to FIG. 1. FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus according to an embodiment. As shown in FIG. 1, the image forming apparatus 1A includes a photosensitive drum 10 as an electrostatic latent image carrier, a charging roller 20 as a charging section, an exposure device 30 as an exposing section, and a developing section as a developing section. A device 40, an intermediate transfer body (intermediate transfer belt) 50, a cleaning device 60 as a cleaning section, a transfer roller 70 as a transfer section, a static elimination lamp 80 as a static elimination section, and an intermediate transfer body cleaning device 90. Be prepared.

The intermediate transfer body 50 is an endless belt stretched between three rollers 51 disposed inside, and is designed to be movable in the direction of the arrow by the three rollers 51. Some of the three rollers 51 also function as transfer bias rollers capable of applying a predetermined transfer bias (primary transfer bias) to the intermediate transfer body 50. An intermediate transfer body cleaning device 90 is arranged near the intermediate transfer body 50 . Further, a transfer roller 70 is disposed near the intermediate transfer body 50 and facing the intermediate transfer body 50, and is used for transferring a developed image (toner image) to a transfer paper P as a recording medium (secondary transfer). A bias (secondary transfer bias) can be applied. A corona charger 52 for applying an electric charge to the toner image on the intermediate transfer body 50 is installed around the intermediate transfer body 50 . The contact portion between the intermediate transfer body 50 and the transfer paper P is disposed between the contact portion between the intermediate transfer body 50 and the transfer paper P.

The developing device 40 includes a developing belt 41 which is a developer carrier, and a developing unit 42 provided around the developing belt 41.

The developing belt 41 is an endless belt stretched between a plurality of belt rollers, and can move in the direction of the arrow in the figure. Further, a portion of the developing belt 41 is in contact with the photosensitive drum 10.

The developing unit 42 includes a black (Bk) developing unit 42K, a yellow (Y) developing unit 42Y, a magenta (M) developing unit 42M, and a cyan (C) developing unit 42C.

The black developing unit 42K includes a developer storage section 421K, a developer supply roller 422K, and a developing roller (developer carrier) 423K. The yellow developing unit 42Y includes a developer storage section 421Y, a developer supply roller 422Y, and a developing roller 423Y. The magenta developing unit 42M includes a developer storage section 421M, a developer supply roller 422M, and a developing roller 423M. The cyan developing unit 42C includes a developer storage section 421C, a developer supply roller 422C, and a developing roller 423C.

Next, a method of forming an image using the image forming apparatus 1A will be described. First, the surface of the photoreceptor drum 10 is uniformly charged using the charging roller 20, and then the photoreceptor drum 10 is exposed to exposure light L using the exposure device 30 to form an electrostatic latent image. . Next, the electrostatic latent image formed on the photoreceptor drum 10 is developed with toner supplied from the developing device 40 to form a toner image. Furthermore, after the toner image formed on the photoreceptor drum 10 is transferred (primary transfer) onto the intermediate transfer body 50 by the transfer bias applied from the roller 51, the toner image formed on the photosensitive drum 10 is transferred (primary transfer) onto the intermediate transfer body 50 by the transfer bias applied from the transfer roller 70. , is transferred (secondary transfer) onto a transfer paper P fed by a paper feeder (not shown). On the other hand, after the toner remaining on the surface of the photosensitive drum 10, on which the toner image has been transferred to the intermediate transfer member 50, is removed by the cleaning device 60, the charge is removed by the charge removal lamp 80. The residual toner on the intermediate transfer body 50 after the image transfer is removed by the intermediate transfer body cleaning device 90.

After the transfer process is completed, the transfer paper P is conveyed to a fixing unit, and the transferred toner image is fixed on the transfer paper P by this fixing unit.

FIG. 2 is a schematic configuration diagram showing another example of an image forming apparatus according to an embodiment. As shown in FIG. 2, the image forming apparatus 1B is different from the image forming apparatus 100A shown in FIG. It has the same configuration as the image forming apparatus 100A except that the unit 42Y, the magenta developing unit 42M, and the cyan developing unit 42C are arranged directly opposite each other.

FIG. 3 is a schematic configuration diagram showing another example of an image forming apparatus according to an embodiment. As shown in FIG. 3, the image forming apparatus 1C is a tandem color image forming apparatus, and includes a copying apparatus main body 110, a paper feed table 120, a scanner 130, an automatic document feeder (ADF) 140, and a secondary It includes a transfer device 150, a fixing device 160 that is a fixing section, and a sheet reversing device 170.

An endless belt-shaped intermediate transfer body 50 is provided in the center of the copying apparatus main body 110. The intermediate transfer body 50 is an endless belt stretched around three rollers 53A, 53B, and 53C, and can move in the direction of the arrow in FIG. An intermediate transfer member cleaning device 90 is arranged near the roller 53B for removing toner remaining on the intermediate transfer member 50 on which the toner image has been transferred to the recording paper. A developing unit 42 (yellow (Y) developing unit 42Y, cyan (yellow (Y) developing unit 42Y, cyan ( C) A developing unit 42C, a magenta (M) developing unit 42M, and a black (Bk) developing unit 42K) are arranged.

Further, an exposure device 30 is arranged near the developing unit 42. Further, a secondary transfer device 150 is arranged on the side of the intermediate transfer member 50 opposite to the side on which the developing unit 42 is arranged. The secondary transfer device 150 includes a secondary transfer belt 151. The secondary transfer belt 151 is an endless belt stretched between a pair of rollers 152, and the recording paper and intermediate transfer body 50 conveyed on the secondary transfer belt 151 are transported between the rollers 53C and 152. contact can be made between.

Further, a fixing device 160 is arranged near the secondary transfer belt 151. The fixing device 160 includes a fixing belt 161, which is an endless belt stretched between a pair of rollers, and a pressure roller 162, which is placed so as to be pressed against the fixing belt 161.

Further, a sheet reversing device 170 is arranged near the secondary transfer belt 151 and the fixing device 160 for reversing the recording paper when forming images on both sides of the recording paper.

Next, a method for forming a full-color image using the image forming apparatus 1C will be described. First, set a color original on the document table 141 of the automatic document feeder (ADF) 140, or open the automatic document feeder 140 and set the color original on the contact glass 131 of the scanner 130, and then Close.

When the start switch (not shown) is pressed, when a color original is set on the automatic document feeder 140, the color original is transported and moved onto the contact glass 131, and then the scanner 130 is driven and the light source is turned on. A first running body 132 and a second running body 133 provided run. On the other hand, as soon as the original is set on the contact glass 131, the scanner 130 is driven, and the first traveling body 132 and the second traveling body 133, which are provided with a light source, travel. At this time, the reflected light from the document surface of the light emitted from the first traveling body 132 is reflected by the mirror of the second traveling body 133, and then received by the reading sensor 136 through the imaging lens 135. A color image) is read to obtain black, yellow, magenta, and cyan image information.

The image information of each color is transmitted to the developing units of each color (yellow developing unit 42Y, cyan developing unit 42C, magenta developing unit 42M, and black developing unit 42K), and toner images of each color are formed.

FIG. 4 is a partially enlarged view of the image forming apparatus shown in FIG. 3. FIG. As shown in FIG. 4, each developing unit (yellow developing unit 42Y, cyan developing unit 42C, magenta developing unit 42M, and black developing unit 42K) has a photosensitive drum 10 (static photosensitive drum 10K for black, photosensitive drum 10K for yellow, Based on the image information of each color, the photoreceptor drum 10Y, the magenta photoreceptor drum 10M, and the cyan photoreceptor drum 10C), the charging roller 20, which is a charging unit that uniformly charges the electrostatic latent image carrier 10, an exposure device 30 that exposes the photoreceptor drum 10 with exposure light L to form an electrostatic latent image of each color on the photoreceptor drum 10; and an exposure device 30 that forms an electrostatic latent image of each color on the photoreceptor drum 10; It includes a developing device 40 which is a developing section that forms an image, a transfer charger 62 for transferring a toner image onto an intermediate transfer body 50, a cleaning device 60, and a static elimination lamp 80.

The toner images of each color formed by the developing units of each color (yellow developing unit 42Y, cyan developing unit 42C, magenta developing unit 42M, and black developing unit 42K) are transferred to intermediate transfer rollers 53A, 53B, and 53C that are stretched over rollers 53A, 53B, and 53C. The images are sequentially transferred onto the body 50 (primary transfer). Then, the toner images of each color are superimposed on the intermediate transfer body 50 to form a composite toner image.

On the other hand, on the paper feed table 120, one of the paper feed rollers 121 is selectively rotated to feed recording paper from one of the paper feed cassettes 123 provided in multiple stages in the paper bank 122. The recording paper is separated one by one by a separation roller 124 and sent to a paper feed path 125. The recording paper is conveyed by a conveyance roller 126 and guided to a paper feed path 111 in the copying apparatus main body 110, and is brought into contact with a registration roller 112. It can be stopped. Alternatively, the recording paper on the manual tray 114 is fed out by rotating the manual feed roller 113, separated one by one by the manual feed roller 113, guided to the manual paper feed path 115, and stopped by hitting the registration roller 112.

Note that the registration roller 112 is generally used while being grounded, but may be used with a bias applied to remove paper dust from the recording paper.

Next, the registration rollers 112 are rotated in synchronization with the composite toner image formed on the intermediate transfer body 50, and the recording paper is sent between the intermediate transfer body 50 and the secondary transfer belt 151, and the composite toner image is is transferred onto recording paper (secondary transfer). Note that toner remaining on the intermediate transfer body 50 to which the composite toner image has been transferred is removed by an intermediate transfer body cleaning device 90.

The recording paper onto which the composite toner image has been transferred is conveyed by a secondary transfer belt 151, and then the composite toner image is fixed onto the recording paper by a fixing device 160.

Thereafter, the conveyance path of the recording paper is switched by a switching claw 116, and the recording paper is discharged onto a paper discharge tray 118 by a discharge roller 117. Alternatively, the conveyance path of the recording paper is switched by the switching claw 116, the recording paper is reversed by the sheet reversing device 170, and guided again to the secondary transfer belt 151, and an image is formed on the back side in the same manner, after which it is ejected. The paper is discharged onto a paper discharge tray 118 by rollers 117 .

<Process cartridge>
The process cartridge according to one embodiment is molded to be removably attached to various image forming apparatuses, and includes an electrostatic latent image carrier carrying an electrostatic latent image, and an electrostatic latent image carrier carried on the electrostatic latent image carrier. It has a developing section that develops a latent image with the developer according to the above embodiment to form a toner image, and may have other configurations as necessary.

The electrostatic latent image carrier is the same as the electrostatic latent image carrier of the image forming apparatus described above, so the details will be omitted.

The developing section includes a developer storage container that stores the developer according to one embodiment, and a developer carrier that supports and transports the developer stored in the developer storage container. Note that the developing section may further include a regulating member or the like in order to regulate the thickness of the developer carried thereon.

FIG. 5 shows an example of a process cartridge according to one embodiment. As shown in FIG. 5, the image forming apparatus process cartridge 200 includes a photosensitive drum 10, a corona charger 22 which is a charging section, a developing device 40, a cleaning device 60, and a transfer roller 70.

Hereinafter, the embodiments will be described in more detail with reference to Examples and Comparative Examples, but the embodiments are not limited to these Examples and Comparative Examples.

<Production Example A-1: Synthesis of amorphous polyester resin A-1>
-Synthesis of prepolymer A-1-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, 3-methyl-1,5-pentanediol, isophthalic acid, and plant-derived sebacic acid were mixed with OH/, which is the molar ratio of hydroxyl groups to carboxyl groups. COOH is 1.1, the composition of the diol component is 100 mol% of 3-methyl-1,5-pentanediol, and the composition of the dicarboxylic acid component is 73 mol% of isophthalic acid and 23 mol% of sebacic acid. Trimethylolpropane was added together with titanium tetraisopropoxide (1,000 ppm based on the resin component) so that the amount of trimethylolpropane was 1.5 mol %. Thereafter, the temperature was raised to 200° C. over about 4 hours, and then to 230° C. over 2 hours, and the reaction was continued until there was no outflow water. Thereafter, the mixture was further reacted for 5 hours under reduced pressure of 10 mmHg to 15 mmHg to obtain [Intermediate Polyester A-1].

Next, the obtained [intermediate polyester A-1] and isophorone diisocyanate (IPDI) were placed in a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube in a molar ratio (isocyanate group of IPDI/intermediate polyester). After diluting with ethyl acetate to make a 50% ethyl acetate solution, the mixture was reacted at 150° C. for 4 hours to obtain [Prepolymer A-1].

-Synthesis of amorphous polyester resin A-1-
The obtained [prepolymer A-1] was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen introduction tube, and [ketimine compound 1] was further added to the amount of isocyanate in [prepolymer A-1]. [Ketimine Compound 1] was added dropwise to the reaction vessel in an amount such that the amount of amine was equimolar, and after stirring at 45° C. for 10 hours, the prepolymer extension product was taken out. The obtained prepolymer extension product was dried under reduced pressure at 50° C. until the amount of residual ethyl acetate became 100 ppm or less to obtain [amorphous polyester resin A-1]. The glass transition temperature (Tg) of the obtained [amorphous polyester resin A-1] was -51°C, and the weight average molecular weight (Mw) was 17,000.

<Production Example A-2: Synthesis of amorphous polyester resin A-2>
-Synthesis of prepolymer A-2-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 3-methyl-1,5-pentanediol, isophthalic acid, and adipic acid were mixed so that the molar ratio of hydroxyl groups to carboxyl groups, OH/COOH, was 1. .1, the composition of the diol component is 100 mol% of 3-methyl-1,5-pentanediol, the composition of the dicarboxylic acid component is 50 mol% of isophthalic acid and 50 mol% of adipic acid, and trimethylolpropane in all monomers. was added together with titanium tetraisopropoxide (1,000 ppm based on the resin component) so that the amount of was 1.5 mol %. Thereafter, the temperature was raised to 200° C. over about 4 hours, and then to 230° C. over 2 hours, and the reaction was continued until there was no outflow water. Thereafter, the mixture was further reacted for 5 hours under reduced pressure of 10 mmHg to 15 mmHg to obtain [Intermediate Polyester A-2].

Next, the obtained [intermediate polyester A-2] and isophorone diisocyanate (IPDI) were placed in a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube in a molar ratio (isocyanate group of IPDI/intermediate polyester). After diluting with ethyl acetate to make a 50% ethyl acetate solution, the mixture was reacted at 150° C. for 4 hours to obtain [Prepolymer A-2].

-Synthesis of amorphous polyester resin A-2-
The obtained [Prepolymer A-2] was stirred in a reaction vessel equipped with a heating device, a stirrer, and a nitrogen introduction tube, and then [Ketimine Compound 1] was added to the amount of isocyanate in [Prepolymer A-2]. [Ketimine Compound 1] was added dropwise to the reaction vessel in an amount such that the amount of amine was equimolar, and after stirring at 45° C. for 10 hours, the prepolymer extension product was taken out. The obtained prepolymer extension product was dried under reduced pressure at 50° C. until the amount of residual ethyl acetate became 100 ppm or less to obtain [Amorphous polyester resin A-2]. The glass transition temperature (Tg) of the obtained [amorphous polyester resin A-2] was -40°C, and the weight average molecular weight (Mw) was 16,500.

<Synthesis of amorphous polyester resin B-1>
Plant-derived propylene glycol, terephthalic acid, and plant-derived succinic acid were added to a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple in a molar ratio of terephthalic acid to succinic acid (terephthalic acid /succinic acid) was 86/14, and the molar ratio of hydroxyl groups to carboxyl groups, OH/COOH, was 1.3. After reacting for 8 hours at 230°C, and further reacting for 4 hours under a reduced pressure of 10 mmHg to 15 mmHg, add trimellitic anhydride to the reaction vessel to give a concentration of 1 mol% based on the total resin components, and then add trimellitic anhydride to the reaction vessel at 180°C and normal pressure for 4 hours. [Amorphous polyester resin B-1] was obtained. The glass transition temperature (Tg) of the obtained [amorphous polyester resin B-1] was 57°C, and the weight average molecular weight (Mw) was 10,000.

<Synthesis of amorphous polyester resin B-2>
In a four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, plant-derived propylene glycol, bisphenol A propylene oxide 2 mole adduct, terephthalic acid, and plant-derived succinic acid were mixed with propylene glycol. The molar ratio of bisphenol A ethylene oxide 2 mole adduct (propylene glycol/bisphenol A 2 mole adduct of ethylene oxide) is 65/35, and the molar ratio of terephthalic acid and succinic acid (terephthalic acid/succinic acid) is 86. /14, and the molar ratio of hydroxyl groups to carboxyl groups, OH/COOH, was prepared to be 1.3, and the mixture was prepared with titanium tetraisopropoxide (500 ppm based on the resin component) at normal pressure and 230°C for 8 hours. After reacting for 4 hours under a reduced pressure of 10 mmHg to 15 mmHg, add trimellitic anhydride to a reaction container to give a concentration of 1 mol% based on the total resin components, and react at 180°C and normal pressure for 4 hours. Crystalline polyester resin B-2] was obtained. The glass transition temperature (Tg) of the obtained [amorphous polyester resin B-2] was 52°C, and the weight average molecular weight (Mw) was 9,000.

<Synthesis of amorphous polyester resin B-3>
In a four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, add 2 moles of bisphenol A ethylene oxide adduct, 2 moles adduct of bisphenol A propylene oxide, terephthalic acid and adipic acid, and add bisphenol A propylene oxide. The molar ratio of the 2 mole adduct of bisphenol A ethylene oxide to the 2 mole adduct of bisphenol A propylene oxide (2 mole adduct of bisphenol A propylene oxide/2 mole adduct of bisphenol A ethylene oxide) is 60/40, and the terephthalic acid and adipic acid The molar ratio (terephthalic acid/adipic acid) is 97/3, and the molar ratio of hydroxyl group to carboxyl group OH/COOH is 1.3. After reacting with 500 ppm) at normal pressure and 230 °C for 8 hours, and then reacting for 4 hours under reduced pressure of 10 mmHg to 15 mmHg, add trimellitic anhydride to the reaction container to make it 1 mol% based on the total resin components, and then at 180 °C. The reaction was carried out at normal pressure for 4 hours to obtain [Amorphous Polyester Resin B-3]. The glass transition temperature (Tg) of the obtained [amorphous polyester resin B-3] was 65°C, and the weight average molecular weight (Mw) was 9,000.

<P-1: Introduction of PET>
When mixing the materials for [Synthesis of amorphous polyester resin] described above, the flaky recycled PET was mixed so as to have the solid content ratio shown in Table 1.

<Synthesis of crystalline polyester resin C-1>
Plant-derived sebacic acid and plant-derived ethylene glycol were added to a 5L four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple at a molar ratio of hydroxyl groups to carboxyl groups of OH/COOH. was 0.9, and reacted with titanium tetraisopropoxide (500 ppm based on the resin component) at 180°C for 10 hours, then heated to 200°C and reacted for 3 hours, and further 8. The reaction was carried out at a pressure of 3 kPa for 2 hours to obtain [crystalline polyester resin C-1]. The melting point of the obtained [crystalline polyester resin C-1] was 72°C, and the weight average molecular weight (Mw) was 20,000.

<Synthesis of crystalline polyester resin C-2>
[Crystalline polyester resin C-2] was obtained in the same manner as in the above <Synthesis of crystalline polyester resin C-1> except that the diol was changed to 1,6-hexanediol. The melting point of the obtained [crystalline polyester resin C-2] was 67°C, and the weight average molecular weight (Mw) was 25,000.

<Synthesis of crystalline polyester resin C-3>
[Crystalline polyester resin C-3] was prepared in the same manner as in <Synthesis of crystalline polyester resin C-1> above, except that the dicarboxylic acid was changed to petroleum-derived sebacic acid and the diol was changed to 1,6-hexanediol. ] was obtained. The melting point of the obtained [crystalline polyester resin C-3] was 65°C, and the weight average molecular weight (Mw) was 25,000.

<Production of crystalline polyester resin dispersion C-1>
45 parts by mass of [crystalline polyester resin C-1] and 450 parts by mass of ethyl acetate were placed in a container equipped with a stirring rod and a thermometer, and the temperature was raised to 80°C while stirring, and after being maintained at 80°C for 5 hours. , cooled to 30° C. for 1 hour, and filled with 80% by volume of zirconia beads with a diameter of 0.5 mm using a bead mill (Ultra Visco Mill, manufactured by Imex) at a liquid feeding rate of 1 kg/hr, a disk circumferential speed of 6 m/sec, Dispersion was performed under 3-pass conditions to obtain [Crystalline polyester resin dispersion C-1]. The volume average particle diameter of the obtained crystalline polyester resin particles was 450 nm, and the solid content concentration of the resin particles was 10%.

<Production of crystalline polyester resin dispersions C-2 and C-3>
[Production of crystalline polyester resin dispersion C-1] except that [crystalline polyester resin C-1] was changed to [crystalline polyester resin C-2] or [crystalline polyester resin C-3]. [Crystalline polyester resin dispersion C-2] and [Crystalline polyester resin dispersion C-3] were obtained in the same manner.

<Preparation of WAX dispersion liquid 1>
720 parts by mass of ion-exchanged water, 180 parts by mass of ester wax (NOF, WE-11, synthetic wax made from plant-derived monomers, melting point 67°C), and 17 parts by mass of anionic surfactant (Daiichi Kogyo Seiyaku) as a surfactant. Neogen SC, sodium dodecylbenzenesulfonate), manufactured by Neogen SC, Co., Ltd., was added. This was dispersed using a homogenizer while being heated to 90° C. to obtain [WAX dispersion 1]. The volume average particle diameter of the wax particles contained in the obtained [WAX dispersion 1] was 300 nm, and the solid content concentration of the resin particles was 25%.

<Preparation of masterbatch (MB) 1>
Adding 1200 parts by mass of water, 500 parts by mass of carbon black (Printex 35, manufactured by Dexa) [DBP oil absorption = 42 mL/100 mg, pH = 9.5], and 500 parts by mass of [amorphous polyester resin B-1], The mixture was mixed using a Henschel mixer (manufactured by Nippon Coke Kogyo Co., Ltd.), and the mixture was kneaded using two rolls at 150° C. for 30 minutes, then rolled and cooled, and pulverized using a pulperizer to obtain [Masterbatch 1].

<Preparation of masterbatch (MB) 2>
[Masterbatch (MB) 1] was prepared in the same manner as [Masterbatch (MB) 1] except that [Amorphous polyester resin B-1] was changed to [Amorphous polyester resin B-3]. Obtained.

<Manufacture of resin particles>
[Example 1]
(Oil phase preparation process)
[Amorphous resin A-2] 50 parts by mass, [Crystalline polyester resin dispersion C-1] 50 parts by mass, [WAX dispersion 1] 50 parts by mass, [Amorphous polyester resin B-3] 550 parts by mass 1, 200 parts by mass of [P-1], and 100 parts by mass of [Masterbatch 1] were placed in a container and mixed at 5,000 rpm for 60 minutes with a TK homomixer (manufactured by Primix Co., Ltd.) to obtain [Oil phase 1]. Ta. Note that the above blending amount indicates the blending amount of solid content in each raw material.

(Aqueous phase preparation process)
990 parts by mass of water, 20 parts by mass of sodium dodecyl sulfate, and 90 parts by mass of ethyl acetate were mixed and stirred to obtain a milky white liquid. This was designated as [aqueous phase 1].

(Manufacturing process of emulsified slurry)
[Oil phase 1] 700 parts by mass was added with 20 parts by mass of 28% ammonia water while stirring at a rotation speed of 8,000 rpm using a TK homomixer, and after mixing for 10 minutes, 1,200 parts by mass of [water phase 1] was added. It was gradually added dropwise to obtain [Emulsified Slurry 1].

(Manufacturing process of solvent removal slurry)
[Emulsified slurry 1] was put into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30°C for 180 minutes to obtain [solvent-free slurry 1].

(Agglomeration process)
30 parts by mass of 5% calcium chloride solution was added dropwise to [solvent removal slurry 1] as an agglomerating salt, stirred for 5 minutes, heated to 60°C, and when the particle size reached 5.0 μm, 30 parts by mass of 5% calcium chloride solution was added dropwise. [Agglomerated slurry 1] was obtained by adding parts by mass and completing the aggregation step.

(fusion process)
[Agglomerated slurry 1] was heated to 70° C. while stirring, and when the desired average circularity reached 0.957, it was cooled to obtain [Dispersed slurry 1].

(Washing/drying process)
After filtering 100 parts of [Dispersion Slurry 1] under reduced pressure, the following operations (1) to (4) were performed three times to obtain [Filter Cake 1].
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 150 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (20 minutes at 12,000 rpm), and then filtered.
(4): 300 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.

The obtained [filter cake 1] was dried at 45° C. for 48 hours in a circulating dryer, and sieved through a mesh with an opening of 75 μm to obtain [resin particle matrix 1].

(External additive treatment process)
[Resin particle matrix 1] 2.0 parts by mass of hydrophobic silica (HDK-2000, manufactured by Clariant Co., Ltd.) as an external additive was mixed with 100 parts by mass in a Henschel mixer, and the mixture was sieved through a 500-mesh sieve. It was allowed to pass through to obtain [Resin Particles 1].

[Examples 2 to 10 and Comparative Examples 1 to 4]
In Example 1, the types and amounts of prepolymer, WAX, crystalline resin, amorphous resin, and PET added in the oil phase adjustment step and aggregation step were changed as shown in Table 1, and the aggregation step Resin particles 2 to 14 were produced in the same manner as in Example 1, except that the type and amount of agglomerating salt and the washing conditions in the washing and drying steps were changed as shown in Table 2.

<Evaluation of characteristics>
The resin particles of each of the above Examples and Comparative Examples were used as toners, and the characteristics of the toners were evaluated for environmental compatibility, low-temperature fixability, image quality, and chargeability. Table 3 shows these evaluation results.

[Environmental compatibility]
Environmental friendliness was evaluated based on the following evaluation criteria based on the ratio of environmentally friendly resin in the toner.
(Evaluation criteria)
A: Environmentally friendly resin ratio (biomass resin + recycled resin) is 60% or more B: Environmentally friendly resin ratio (biomass resin + recycled resin) is 30% or more and less than 60% C: Environmentally friendly resin ratio (biomass resin + recycled resin) is less than 30%

[Low temperature fixability]
A developer was obtained by mixing the carrier used in imageo MP C5503 (manufactured by Ricoh Co., Ltd.) and the resin particles obtained above so that the resin particle concentration was 5% by mass. After putting the developer into the unit of imageo MP C5503 (manufactured by Ricoh Co., Ltd.), place a 2 cm x 15 cm rectangular solid image on PPC paper type 6000 <70W> A4 T (manufactured by Ricoh Co., Ltd.) with the amount of toner attached. It was formed to have a concentration of 0.40 mg/cm2. At this time, the surface temperature of the fixing roller is changed, and it is observed whether a cold offset occurs in which the undeveloped image of the solid image is fixed in a location other than the desired location, and the low-temperature fixing performance is evaluated based on the following evaluation criteria. evaluated.
(Evaluation criteria)
A: Less than 110°C B: 110°C or more and less than 125°C C: 125°C or more

[Image quality]
Image quality was evaluated by looking at the reproducibility of fine lines. The resin particles are placed in imageo MP C5503 (manufactured by Ricoh Co., Ltd.), and a 6-point and 10-point character printing test is performed. The reproducibility of printed characters was evaluated in three stages based on the following evaluation criteria.
(Evaluation criteria)
A: 6 point characters are clear B: 6 point characters are partially crushed C: 10 point characters are partly crushed

[Charging property]
The carrier used in imageo MP C5503 (manufactured by Ricoh Co., Ltd.) and the resin particles obtained above were mixed so that the concentration of the resin particles was 7% by mass to obtain a developer. The developer was set in imageo MP C5503 (manufactured by Ricoh Co., Ltd.), and a running evaluation of 300,000 sheets was performed on an image chart with a 50% image area in single color mode. Then, the amount of change in the amount of charge of the carrier after this running was judged based on the following evaluation criteria, and the chargeability was evaluated. The amount of charge change is as follows. That is, after conditioning the humidity in an unsealed system for 30 minutes or more in an environment with an air temperature of 23°C and a relative humidity of 50% (M/M environment), and adding 6.000 g of initial carrier and 0.452 g of toner to a stainless steel container. The samples were sealed and tribo-electrified using a YS-LD (Yayoi shaker) operated at a scale of 150 for 5 minutes and shaken approximately 1,100 times using the general blow-off method (Toshiba). The amount of charge measured using a chemical company (TB-200) was defined as Q1, and the amount of charge measured using the same method on the carrier obtained by removing the toner in the developer after running using the blow-off device was defined as Q2. It refers to |Q1-Q2| of the time.
(Evaluation criteria)
A: Charge amount change is less than 10 μc/g B: Charge amount change is 10 μc/g or more and less than 20 μc/g C: Charge amount change is 20 μc/g or more

[comprehensive evaluation]
The overall evaluation was evaluated based on the following evaluation criteria. If there are three or more A's in all evaluation items and the rest are B's, it is "A". If there are two A's in all evaluation items and the rest are B's, it is "B", and if there is one A in the evaluation item. A score of "C" was given when the remaining score was "B", and a score of "D" was given when one or more of the evaluation items were "C".
(Evaluation criteria)
A: Very good B: Excellent C: Slightly better than conventional D: Not suitable for practical use

From Table 3, it was confirmed that the resin particles of Examples 1 to 10 were toners that met the usage conditions in terms of environmental friendliness, low-temperature fixability, image quality, and chargeability. On the other hand, the resin particles obtained in Comparative Examples 1 to 4 did not meet the usage conditions in at least one of environmental compatibility, low-temperature fixability, image quality, and chargeability, and caused practical problems. It was confirmed that the toner had a

Therefore, unlike the resin particles of Comparative Examples 1 to 4, the resin particles of Examples 1 to 10 contained PET or PBT, had a radiocarbon isotope ^14C concentration of 10.8 pMC or more, and did not contain any external additives. By containing 0.05% by mass to 1% by mass of a divalent metal element, it can be said that a high-quality toner with excellent environmental friendliness, low-temperature fixability, image quality, and chargeability can be provided.

Although the embodiments have been described as above, the embodiments are presented as examples, and the present invention is not limited to the embodiments described above. The embodiments described above can be implemented in various other forms, and various combinations, omissions, substitutions, changes, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, as well as within the scope of the invention described in the claims and its equivalents.

Note that aspects of the embodiment of the present invention are, for example, as follows.
<1> Resin particles containing polyethylene terephthalate or polybutylene terephthalate,
The radiocarbon isotope ^14C concentration of the resin particles is 10.8 pMC or more,
Resin particles containing 0.05% by mass to 1% by mass of a divalent metal element excluding external additives.
<2> Contains at least one of an amorphous resin, an amorphous resin, and a crystalline resin,
At least one or more of the amorphous resin, the amorphous resin, and the crystalline resin includes a biomass-derived resin,
The resin particles according to <1>, wherein the total content of the biomass-derived resin and the polyethylene terephthalate or the polybutylene terephthalate is 50% by mass or more based on the total mass of the resin particles.
<3> The resin particles according to <2>, wherein the polyethylene terephthalate or the polybutylene terephthalate is contained in a larger amount than the biomass-derived resin.
<4> The resin particles according to any one of <1> to <3>, wherein the content of magnesium among the divalent metal elements is 0.1% by mass to 0.5% by mass.
<5> The resin particles contain sodium,
Among the divalent metal elements, magnesium is contained more than sodium,
The resin particles according to any one of <1> to <4>, wherein the sodium content exceeds 0.05% by mass.
<6> A toner comprising the resin particles according to any one of <1> to <5>.
<7> A developer comprising the toner according to <6> and a carrier.
<8> A toner storage unit containing the toner described in <6>.
<9> Electrostatic latent image carrier;
an electrostatic latent image forming section that forms an electrostatic latent image on the electrostatic latent image carrier;
a developing section that develops the electrostatic latent image using toner to form a visible image;
a transfer unit that transfers the visible image to a recording medium;
a fixing unit that fixes the transferred image transferred to the recording medium,
An image forming apparatus, wherein the toner is the toner according to <6>.
<10> An electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier;
a developing step of developing the electrostatic latent image using toner to form a visible image;
a transfer step of transferring the visible image to a recording medium;
a fixing step of fixing the transferred image transferred to the recording medium,
An image forming method, wherein the toner is the toner according to <6>.

1A, 1B, 1C Image forming device 10 Electrostatic latent image carrier (photosensitive drum)
20 Charging roller (charging part)
30 Exposure device (exposure section)
40 Developing device (developing section)
50 Intermediate transfer body (intermediate transfer belt)
60 Cleaning device (cleaning section)
70 Transfer roller (transfer section)
80 Static elimination lamp (static elimination section)

Patent No. 6138021

Claims (10)

Resin particles containing polyethylene terephthalate or polybutylene terephthalate,
The radiocarbon isotope ^14C concentration of the resin particles is 10.8 pMC or more,
Resin particles containing 0.05% by mass to 1% by mass of a divalent metal element excluding external additives. Containing at least one of an amorphous resin, an amorphous resin, and a crystalline resin,
At least one or more of the amorphous resin, the amorphous resin, and the crystalline resin includes a biomass-derived resin,
The resin particles according to claim 1, wherein the total content of the biomass-derived resin and the polyethylene terephthalate or the polybutylene terephthalate is 50% by mass or more with respect to the total mass of the resin particles. The resin particles according to claim 2, wherein the polyethylene terephthalate or the polybutylene terephthalate is contained in a larger amount than the biomass-derived resin. The resin particles according to claim 1, wherein the content of magnesium among the divalent metal elements is 0.1% by mass to 0.5% by mass. the resin particles contain sodium,
Among the divalent metal elements, magnesium is contained more than sodium,
The resin particles according to claim 1, wherein the content of sodium exceeds 0.05% by mass. A toner comprising the resin particles according to any one of claims 1 to 5. A developer comprising the toner according to claim 6 and a carrier. A toner storage unit containing the toner according to claim 6. an electrostatic latent image carrier;
an electrostatic latent image forming section that forms an electrostatic latent image on the electrostatic latent image carrier;
a developing section that develops the electrostatic latent image using toner to form a visible image;
a transfer unit that transfers the visible image to a recording medium;
a fixing unit that fixes the transferred image transferred to the recording medium,
An image forming apparatus, wherein the toner is the toner according to claim 6. an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier;
a developing step of developing the electrostatic latent image using toner to form a visible image;
a transfer step of transferring the visible image to a recording medium;
a fixing step of fixing the transferred image transferred to the recording medium,
An image forming method, wherein the toner is the toner according to claim 6.

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