JP2017097161A - Image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method, in a cleanerless system effective in reduction in size of a printer and elimination of waste, which has suppressed the occurrence of fogging and a failure in charging of toner due to contamination of a member, such as a toner carrier when a talc sheet is used as a medium.SOLUTION: The present invention is an image forming method including a cleanerless system, wherein a toner contains toner particles containing a binder resin and a colorant and inorganic fine particles; the inorganic fine particles include titanate fine particles A of the II group element and silica fine particles B; the titanate fine particles A of the II group element and silica fine particles B each have a predetermined particle diameter and a predetermined ratio of fastening to the toner particles; the toner has an aspect ratio of 0.880 or more; the toner has a predetermined adhesive force between two particles.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image forming method used in electrophotography.

In recent years, printers and copiers have high image quality and high durability, and at the same time, printers are particularly required to be small and waste-free.
The printer must be adapted to various business scenes such as a network printer used by a large number of people and a personal printer used in SOHO or the like via a network. Also, in the office and SOHO environment, maintenance-free against waste generation such as waste toner replacement is strongly desired. Accordingly, there is still a strong demand for space saving of the printer, that is, downsizing and wasteless.

Regarding the downsizing of the printer, it is mainly effective to downsize the fixing device and downsize the process cartridge. In particular, the process cartridge occupies most of the volume of the printer, and downsizing of the process cartridge can greatly contribute to downsizing of the printer.
Regarding the downsizing of the process cartridge, downsizing of the developing device and the cleaning device is effective. Focusing on the downsizing of the developing device, there are a two-component developing method and a one-component developing method as an electrophotographic developing method, but the one-component developing method is suitable for downsizing. This is because a member such as a carrier is not used.

  Further, focusing on the cleaning device, a cleanerless system that does not have a cleaning device is very suitable for downsizing the process cartridge. In many printers, the toner (transfer residual toner) remaining on the electrostatic latent image carrier (photoreceptor) remaining in the transfer process is scraped off by a cleaning blade or the like and collected in a cleaning container to become waste toner. On the other hand, the cleanerless system does not have a cleaning blade or cleaning container, and the transfer residual toner is collected again by the developing device and contributes to development. Therefore, the process cartridge can be greatly reduced in size, and waste toner is eliminated without generating waste toner. Can also contribute greatly.

  However, there are unique challenges with cleanerless systems. One of them is that a filler such as paper, which is a medium, or an additive adheres to the surface of the photosensitive member and is collected by the developing device as a foreign substance. If these foreign substances are fixed and fused to each member in the process cartridge, there is a case where an adverse effect on the image is likely to occur because charging to the toner is not properly performed. In particular, when paper containing talc is used as the media, when talc is collected in the developing device, it becomes easy to adhere and fuse to the toner carrier due to its cleavage property, and at the same time, due to its charge imparting property, the charging of the toner It becomes easy to reduce the amount. As a result, the toner having a reduced charge amount is likely to cause image detrimental effects such as fogging and non-regular development in the non-image area. This fog phenomenon tends to occur particularly remarkably at high temperature and high humidity, where the charge amount of the toner is relatively low.

In a process cartridge having a conventional cleaning device, the foreign matter is scraped off by a cleaning blade and collected together with waste toner in a cleaner container.
As a means for suppressing image damage when talc paper is used as a medium, a method has been proposed in which brush cleaning is performed on an intermediate transfer member so that talc does not reach the toner carrier (Patent Document 1). In addition, as a means for suppressing the same image adverse effect, a method has been proposed in which a non-woven pad made of ultrafine fibers is attached to the surface of a photoreceptor and talc is scraped off (Patent Document 2). In these, it is difficult to reduce the size of the printer because of the addition of members, and it is also difficult to reduce the waste of the printer because it is necessary to remove the collected talc.
As described above, although there is an effective means called a cleaner-less system for downsizing the printer and reducing waste, the cleaner-less system has not yet solved the problem related to the image damage.

JP 2011-59280 A JP 2006-267485 A

  An object of the present invention is to provide a cleaner-less system effective for downsizing a printer and reducing waste, and when toner particles such as talc paper are used as media, the toner carrier is contaminated with toner, resulting in poor toner charging and fogging. An object of the present invention is to provide an image forming method in which generation is suppressed.

The present invention includes a charging step for charging an electrostatic latent image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the charged electrostatic latent image carrier, and the electrostatic latent image as a toner. A developing step of developing with a toner on a carrier to form a toner image, a transferring step of transferring the toner image to a transfer material, and a fixing step of fixing the toner image transferred to the transfer material to the transfer material An image forming method comprising:
The developing step also serves as a step of collecting the toner remaining on the electrostatic latent image carrier after the transfer step with the toner carrier.
The toner has toner particles containing a binder resin and a colorant and inorganic fine particles,
The inorganic fine particles have Group 2 element titanate fine particles A and silica fine particles B;
The second group titanate fine particles A have a primary particle number average particle diameter (D1) of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 40 mass% or more and 85 mass% or less.
The silica fine particle B has a number average particle diameter (D1) of primary particles of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 50 mass% or more and 95 mass% or less.
The aspect ratio of the toner is 0.880 or more,
When the adhesion between two particles when a load of 78.5 N is applied to the toner is Fp (A), and the adhesion between two particles when a load of 157.0 N is applied to the toner is Fp (B) The present invention relates to an image forming method characterized by satisfying the following formulas (1) and (2).
Fp (A) ≦ 30.0 nN (1)
(Fp (B) −Fp (A)) / Fp (A) ≦ 0.60 (2)

  According to the present invention, in a cleaner-less system effective for downsizing the printer and reducing waste, toner charging failure and fogging due to contamination of a member on a toner carrier when talc paper or the like is used as a medium can be prevented. A suppressed image forming method can be provided.

1 is a schematic diagram illustrating an example of an image forming apparatus to which an image forming method of the present invention can be applied. It is a schematic diagram which shows an example of the apparatus which measures the adhesive force between two particles in this invention. 2 is an example of measurement data of a weight-based particle size distribution of silica fine particles B. FIG. 2 is a schematic diagram illustrating an example of a toner thermal spheronization processing apparatus.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments.
The present invention includes a charging step for charging the electrostatic latent image carrier,
An electrostatic latent image forming step of forming an electrostatic latent image on the charged electrostatic latent image carrier;
A developing step of developing the electrostatic latent image with toner on a toner carrier to form a toner image;
A transfer step of transferring the toner image to a transfer material;
A fixing step of fixing the toner image transferred to the transfer material to the transfer material,
The developing step also serves as a step of collecting the toner remaining on the electrostatic latent image carrier after the transfer step with the toner carrier.
The toner has toner particles containing a binder resin and a colorant and inorganic fine particles,
The inorganic fine particles have Group 2 element titanate fine particles A and silica fine particles B;
The second group titanate fine particles A have a primary particle number average particle diameter (D1) of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 40 mass% or more and 85 mass% or less.
The silica fine particle B has a number average particle diameter (D1) of primary particles of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 50 mass% or more and 95 mass% or less.
The aspect ratio of the toner is 0.880 or more,
When the adhesion force between two particles when a load of 78.5 N is applied to the toner is Fp (A), and the adhesion force between two particles when a load of 157.0 N is applied to the toner is Fp (B) The image forming method is characterized by satisfying the following formulas (1) and (2).
Fp (A) ≦ 30.0 nN (1)
(Fp (B) −Fp (A)) / Fp (A) ≦ 0.60 (2)

  As shown in FIG. 1, the image forming method of the present invention does not have a cleaning process in which the transfer residual toner remaining in the transfer process is scraped off with a cleaning blade or the like. Collected and contributed again to development. That is, the image forming method of the present invention is a so-called cleaner-less system having a so-called development and recovery process.

  In the cleanerless system, as described above, fillers and additives such as media, which are media, may adhere to the surface of the photoconductor and be collected as foreign matter by the developing device. If these foreign substances are fixed and fused to each member in the process cartridge, there is a case where an adverse effect on the image is likely to occur because charging to the toner is not properly performed. In particular, when paper containing talc is used as the media, when talc is collected in the developing device, it becomes easy to adhere and fuse to the toner carrier due to its cleavage property, and at the same time, due to its charge imparting property, the charging of the toner It becomes easy to reduce the amount. As a result, the toner having a reduced charge amount is likely to cause image detrimental effects such as fogging and non-regular development in the non-image area. This fog phenomenon tends to occur particularly remarkably at high temperature and high humidity, where the charge amount of the toner is relatively low.

  Talc is highly adherent to the member due to its cleavage property, and particularly tends to be attached and fused on a rotating member such as a toner carrier as a frictional charge imparting member. In addition, talc is known to have a strong negative chargeability, and if it adheres to and fuses with a toner carrier, the charge amount of the negatively chargeable toner tends to be reduced, especially under high temperature and high humidity. The toner charge amount is remarkably reduced, and image defects such as fogging are likely to occur.

  Therefore, in the present invention, the particle size of the inorganic fine particles having a high polishing effect and high fluidity in the toner, the presence state (fixing rate) on the toner surface, the aspect ratio of the toner and the adhesion between the two particles are controlled. . As a result, the talc and other foreign matters adhered and fused on the toner carrying member are well polished at the nip portion with the toner regulating member, and further, following the minute irregularities on the toner carrying member and rolling well, The effect can be further promoted. And it discovered that adhesion and fusion | bonding to the surface of a toner carrier of foreign materials, such as a talc, can be suppressed.

  In the present invention, the talc mixed in the toner is imparted with fluidity to the low-fluidity talc by allowing the inorganic fine particles to exist to a certain extent from the toner surface to the talc surface. Relieves strong negative chargeability. In this way, it has been found that talc can be developed together with toner, and can be discharged out of the system by transferring it together with toner to paper or the like in the transfer process.

The inorganic fine particles used in the present invention include group 2 element titanate fine particles A and silica fine particles B.
In the second group titanate fine particles A, the number average particle diameter (D1) of primary particles is 80 nm or more and 200 nm or less, and the fixing ratio to the toner particles is 40% by mass or more and 85% by mass or less.
The number average particle diameter of the group 2 titanate fine particles A and the fixing ratio to the toner particles are within this range, so that both the above-mentioned polishing effect and fluidity are achieved, and further, the migration to foreign substances such as talc. The property is also good.
When the number average particle size of the titanate fine particles A is less than 80 nm, the above-mentioned polishing effect is reduced, and embedding in the toner surface is caused to reduce the fluidity of the toner, and also to foreign matters such as talc. The transferability of will also be reduced. When the number average particle diameter of the titanate fine particles A exceeds 200 nm, it becomes difficult to be held on the surface of the toner particles, the polishing effect is lowered, and the titanate fine particles A adhere to and melt on other members. You may wear it.
Further, when the adhesion rate to the toner particles is less than 40% by mass, the member is likely to be contaminated. When it exceeds 85% by mass, embedding on the toner surface occurs and the fluidity of the toner is lowered. May end up.

The silica fine particles B have a number average particle diameter (D1) of primary particles of 80 nm to 200 nm and a fixation rate to the toner particles of 50 mass% to 95 mass%.
When the number average particle diameter of the silica fine particles B and the fixing ratio to the toner particles are within this range, the fluidity can be imparted to the toner, and further the rolling effect can be promoted by rolling well. .
When the number average particle diameter of the silica fine particles B is less than 80 nm, the fluidity of the toner is lowered, the polishing effect is lowered, and the migration to foreign substances such as talc is also lowered. When the number average particle diameter of the silica fine particles exceeds 200 nm, it becomes difficult to be held on the surface of the toner particles, the fluidity of the toner is lowered, and the polishing effect is lowered.
In addition, if the adhesion rate to the toner particles is less than 50% by mass, this also tends to cause contamination of the member, and if it exceeds 95% by mass, embedding in the toner surface occurs and the fluidity of the toner is reduced. There is a case to let you.

  Next, the aspect ratio of the toner used in the present invention is 0.880 or more. When the aspect ratio of the toner is 0.880 or more, the uniformity of diffusion and fixation of the inorganic fine particles to the toner particle surface is improved, and the toner is likely to have a point contact state through the inorganic fine particles. . Furthermore, the above-mentioned polishing effect can be promoted by the high fluidity of the toner itself and good rolling. When the aspect ratio of the toner is less than 0.880, the inorganic fine particles are likely to move to the recesses on the surface of the toner particles, and the fluidity and abrasiveness may be lowered.

Next, the toner used in the present invention has an adhesion force between two particles when a load of 78.5 N is applied, Fp (A), and an adhesion force between two particles when a load of 157.0 N is applied to the toner. When Fp (B) is satisfied, the following expressions (1) and (2) are satisfied.
Fp (A) ≦ 30.0 nN (1)
(Fp (B) −Fp (A)) / Fp (A) ≦ 0.60 (2)
When the adhesion force between the two particles of the toner is within this range, the fluidity of the toner becomes good, and the fluidity and abrasiveness can be maintained over a long period of time. In addition, the toner is easily released even after the toner is compacted, such as after long-term storage under high temperature and high humidity. It is also possible to make it.

Here, the compression conditions of 78.5N (A) and 157.0N (B) will be described. These compression conditions are values assuming a load applied when the toner compacted in the process cartridge passes through the restricting portion.
In recent years, assuming that the printer is downsized, a toner carrier having an outer diameter of about 10 mm to 14 mm is often used. The torque applied to such a small-diameter toner carrier is about 0.1 N · m to 0.3 N · m on the shaft. Therefore, a force of about 20 N to 60 N is applied between the surface of the toner carrier and the regulating blade. In the future, if the diameter of the toner carrier is further reduced, it is expected that a load exceeding the above will be applied to the regulating portion.

Accordingly, the load of 78.5 N (A) is assumed to be a structure in which the load is about 20% stronger than the conventional load in consideration of the reduction in the diameter of the printer, and the deteriorated toner after the endurance enters the regulating portion. It is a value that assumes.
On the other hand, the load of 157.0 N (B) is a value that assumes a state in which the fluidity of the toner is reduced by half, that is, a state where the toner has deteriorated in durability and is further consolidated in the above-described cartridge configuration that can be taken in the future. . As described above, there is a case where a large load is applied when the very compact toner in the process cartridge after being stored for a long time after being rushed enters the regulating portion.

  The group 2 element titanate fine particles A that can be used in the present invention may be made of known materials, but the primary particles have a cubic and / or rectangular parallelepiped shape and a perovskite crystal structure. It is preferable to have. When the shape of the primary particles of the Group 2 element titanate fine particles A has a cubic and / or rectangular parallelepiped shape, the toner can have a high polishing effect. Further, as the group 2 element titanate fine particles A, calcium titanate, barium titanate, strontium titanate and the like are preferable, and strontium titanate is particularly preferable.

The group 2 element titanate fine particles A and / or silica fine particles B that can be used in the present invention are preferably subjected to a known surface treatment such as a hydrophobic treatment. As the surface treatment agent, silicone oil, HMDS (hexamethyldisilazane), alkylsilane, and the like are preferable from the viewpoint that excellent fluidity and releasability can be obtained, but considering the chargeability under high temperature and high humidity. Alkylsilane is particularly preferred.
Specific examples of the alkylsilane include alkyltrialkoxysilanes represented by the following formula (3) such as octyltriethoxysilane.

  The silica fine particles B that can be used in the present invention preferably have a maximum peak half-value width (full width at half maximum) of 25 nm or less in a weight-based particle size distribution curve. When the half-value width of the maximum peak is 25 nm or less, the uniformity of diffusion and fixing to the toner particle surface is improved, and further, the effect of crushing the titanate fine particles A at the time of external addition mixing is also exhibited. As a result, the fluidity and polishability can be further improved.

  The aspect ratio of the toner that can be used in the present invention is preferably 0.900 or more. When the aspect ratio of the toner is 0.900 or more, the uniformity of diffusion and fixation of the inorganic fine particles to the toner particle surface is further improved, and the point contact state between the toners via the inorganic fine particles is further improved. Can be made.

Next, the material configuration and manufacturing method that can be used for the toner of the present invention will be described in detail.
First, toner particles and toner that can be used in the present invention will be described in detail.
For the toner particles that can be used in the present invention, any known production method such as a dry method, an emulsion polymerization method, a solution suspension method, or a suspension polymerization method can be used. In the present invention, the toner aspect ratio is 0.880 or more. For this reason, surface modification treatment such as thermal spheronization treatment in the dry method, suspension polymerization method is preferred in the polymerization method, particularly preferably, the polymerizable monomer composition is granulated in an aqueous medium, It is produced by a suspension polymerization method that forms particles of a polymerizable monomer composition.

Hereinafter, the suspension polymerization method will be described in detail.
As the polymerizable monomer, a vinyl monomer capable of radical polymerization is used. As the vinyl monomer, a monofunctional monomer or a polyfunctional monomer can be used.
The following are mentioned as a monofunctional monomer.
Styrene; α-methyl styrene, β-methyl styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, p-phenyl styrene, styrene derivatives; methyl acrylate, ethyl acrylate, n- Acrylic polymerizable monomers such as propyl acrylate, iso-propyl acrylate, n-butyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate; such as methyl methacrylate, ethyl methacrylate, dibutyl phosphate ethyl methacrylate Methacrylic polymerizable monomers; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate and vinyl propionate; vinyl methyl ether, vinyl ethyl ether, vinyl Vinyl ethers such as isobutyl ether; vinyl methyl ketone, vinyl hexyl ketone, vinyl ketones such as vinyl isopropyl ketone.

Among the above, the polymerizable monomer preferably contains styrene or a styrene derivative.
The following are mentioned as a polyfunctional monomer.
Diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinyl ether and the like.
You may use the above-mentioned monofunctional monomer individually or in combination of 2 or more types, or combining the above-mentioned monofunctional monomer and polyfunctional monomer. Polyfunctional monomers can also be used as crosslinking agents.

  As the polymerization initiator that can be used in the present invention, an oil-soluble initiator and / or a water-soluble initiator is used. Preferably, the half-life at the reaction temperature during the polymerization reaction is 0.5 to 30 hours. Further, when the polymerization reaction is carried out at an addition amount of 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer, a polymer having a maximum value between 10,000 and 100,000 is usually obtained. It is preferable because toner particles having excellent strength and melting characteristics can be obtained.

The following can be illustrated as a polymerization initiator.
2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis Azo or diazo polymerization initiators such as -4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylper Such as oxypivalate, t-butylperoxyisobutyrate, t-butylperoxyneodecanoate, methyl ethyl ketone peroxide, diisopropylperoxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide Peroxide-based polymerization initiators, etc.
In the present invention, in order to control the degree of polymerization of the polymerizable monomer, a known chain transfer agent, polymerization inhibitor or the like can be further added and used.

In the present invention, the polymerizable monomer composition may contain a polyester resin.
Examples of the polyester resin that can be used in the present invention include the following.
Examples of the divalent acid component include the following dicarboxylic acids or derivatives thereof.
Benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or their anhydrides or lower alkyl esters thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid or their anhydrides or lower thereof Alkyl esters; alkenyl succinic acids or alkyl succinic acids such as n-dodecenyl succinic acid, n-dodecyl succinic acid, or anhydrides thereof or lower alkyl esters thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid Or its anhydride or its lower alkyl ester.

The following are mentioned as a bivalent alcohol component.
Ethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol (CHDM), hydrogenated bisphenol A, formula (1) ) Bisphenol and its derivatives:

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 to 10.)

The polyester resin that can be used in the present invention may contain the following components as components other than the above-described divalent carboxylic acid compound and divalent alcohol compound.
Monovalent carboxylic acid compound, monovalent alcohol compound, trivalent or higher carboxylic acid compound, trivalent or higher alcohol compound.
Examples of the monovalent carboxylic acid compound include aromatic carboxylic acids having 30 or less carbon atoms such as benzoic acid and p-methylbenzoic acid, and aliphatic carboxylic acids having 30 or less carbon atoms such as stearic acid and behenic acid. .

Examples of monovalent alcohol compounds include aromatic alcohols having 30 or less carbon atoms such as benzyl alcohol, and aliphatic alcohols having 30 or less carbon atoms such as lauryl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol. It is done.
Although it does not restrict | limit especially as a trivalent or more carboxylic acid compound, A trimellitic acid, trimellitic anhydride, pyromellitic acid, etc. are mentioned.
Examples of the trivalent or higher alcohol compound include trimethylolpropane, pentaerythritol, and glycerin.

The production method of the polyester resin that can be used in the present invention is not particularly limited, and a known method can be used.
The polyester resin that can be used in the present invention may be a crystalline polyester resin.
As the alcohol component used for the raw material monomer of the crystalline polyester resin, it is preferable to use an aliphatic diol having 6 to 18 carbon atoms from the viewpoint of enhancing crystallinity. Among these, an aliphatic diol having 6 to 12 carbon atoms is preferable from the viewpoint that excellent fixing property and heat stability can be obtained.

  Examples of the aliphatic diol include 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1, Examples include 12-dodecanediol. The content of the aliphatic diol is preferably 80.0 mol% or more and 100.0 mol% or less in the alcohol component from the viewpoint of further improving the crystallinity of the crystalline polyester resin.

As an alcohol component for obtaining crystalline polyester resin, you may contain polyhydric alcohol components other than said aliphatic diol. For example, the following are mentioned.
A bisphenol represented by the above formula (I) containing a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane, a polyoxyethylene adduct of 2,2-bis (4-hydroxyphenyl) propane and the like Aromatic diols such as alkylene oxide adducts of A; trihydric or higher alcohols such as glycerin, pentaerythritol, trimethylolpropane.

As the carboxylic acid component used for the raw material monomer of the crystalline polyester resin, an aliphatic dicarboxylic acid compound having 6 to 18 carbon atoms is preferably used. Among these, an aliphatic dicarboxylic acid compound having 6 to 12 carbon atoms is preferable from the viewpoint of improving the fixing property and heat stability of the toner.
Examples of the aliphatic dicarboxylic acid compound include 1,8-octanedioic acid, 1,9-nonanedioic acid, 1,10-decanedioic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, and the like. It is done. The content of the aliphatic dicarboxylic acid compound having 6 to 18 carbon atoms is preferably 80.0 mol% or more and 100.0 mol% or less in the carboxylic acid component.

As a carboxylic acid component for obtaining a crystalline polyester resin, a carboxylic acid component other than the aliphatic dicarboxylic acid compound may be contained. For example, an aromatic dicarboxylic acid compound, a trivalent or higher valent aromatic polycarboxylic acid compound, and the like can be mentioned, but the invention is not particularly limited thereto. The aromatic dicarboxylic acid compound also includes an aromatic dicarboxylic acid derivative. Specific examples of the aromatic dicarboxylic acid compound include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, anhydrides of these acids, and alkyl (1 to 3 carbon atoms) esters thereof. . Examples of the alkyl group in the alkyl ester include a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the trivalent or higher polyvalent carboxylic acid compound include the following.
Aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and their acid anhydrides, alkyls (C 1 or more and 3 or less) ) Derivatives such as esters.

In the present invention, the polymerizable monomer composition may contain a wax as a release agent.
As the wax, hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax are preferable from the viewpoint of high releasability. If necessary, two or more kinds of waxes may be used in combination.

Specific examples of the wax include the following.
Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries), high wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals, Inc.) Co., Ltd.), Sazol H1, H2, C80, C105, C77 (Schumann Sazol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seiwa Co., Ltd.) )), Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Adress Co., Ltd.), wood wax, beeswax, rice wax , Candelilla wax, carnauba wax (available from Celerica NODA).
The added amount of the wax is preferably 1.0 to 20.0 parts by mass of wax with respect to the binder resin.

The toner particles that can be used in the present invention may be magnetic toner particles or non-magnetic toner particles.
When manufacturing as magnetic toner particles, it is preferable to use magnetic iron oxide as magnetic fine particles. As the magnetic iron oxide, iron oxides such as magnetite, maghematite, and ferrite are used. The amount of magnetic iron oxide contained in the toner is preferably 25.0 parts by mass or more and 100.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin.

  When producing non-magnetic toner particles, carbon black or other known pigments or dyes can be used as the colorant. Further, only one kind of pigment or dye may be used, or two or more kinds may be used in combination. The amount of the colorant contained in the toner is preferably 0.1 parts by mass or more and 60.0 parts by mass or less, more preferably 0.5 parts by mass or more and 50.50 parts by mass or less with respect to 100 parts by mass of the binder resin. 0 parts by mass or less.

  The magnetic fine particles that can be used in the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. Air was blown in while maintaining the pH of the prepared aqueous solution at 7 or higher, and ferrous hydroxide was oxidized while the aqueous solution was heated to 70 ° C. or higher. First, seed crystals serving as the core of the magnetic iron oxide powder were formed. Generate.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. While maintaining the pH of the solution at 5 to 10, the reaction of ferrous hydroxide proceeds while blowing air to grow magnetic iron oxide powder with the seed crystal as the core. At this time, the shape and magnetic characteristics of the magnetic fine particles can be controlled by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5. The magnetic fine particles can be obtained by filtering, washing, and drying the magnetic fine particles thus obtained by a conventional method.

  In the present invention, when the toner is produced by the suspension polymerization method, it is very preferable to subject the surface of the magnetic fine particles to a hydrophobic treatment. When the surface treatment is performed by a dry method, the coupling agent treatment is performed on the washed, filtered, and dried magnetic fine particles. When wet surface treatment is performed, after the oxidation reaction is completed, the dried product is redispersed, or after completion of the oxidation reaction, the iron oxide body obtained by washing and filtering is not dried but in another aqueous medium. The dispersion is redispersed and a coupling treatment is performed. Specifically, a silane coupling agent is added while stirring the redispersion sufficiently, and the temperature is increased after hydrolysis, or the coupling is performed by adjusting the pH of the dispersion to an alkaline region after hydrolysis. . Among these, from the viewpoint of performing a uniform surface treatment, it is preferable to carry out the surface treatment by reslurry as it is without drying after filtration and washing after completion of the oxidation reaction.

  In order to treat the surface of the magnetic fine particles with a wet method, that is, to treat the magnetic fine particles with a coupling agent in an aqueous medium, first, sufficiently disperse the magnetic fine particles in the aqueous medium so as to have a primary particle size so as not to settle or aggregate. Stir with a stirring blade. Next, an arbitrary amount of the coupling agent is added to the dispersion, and the surface treatment is performed while the coupling agent is hydrolyzed. At this time, the agglomeration is sufficiently carried out using a device such as a pin mill or a line mill while stirring. It is more preferable to perform the surface treatment while dispersing.

  Here, the aqueous medium is a medium containing water as a main component. Specific examples include water itself, water added with a small amount of surfactant, water added with a pH adjuster, and water added with an organic solvent. As the surfactant, nonionic surfactants such as polyvinyl alcohol are preferable. The surfactant is preferably added in an amount of 0.1 to 5.0% by mass with respect to water. Examples of the pH adjuster include inorganic acids such as hydrochloric acid. Examples of the organic solvent include alcohols.

  Examples of the coupling agent for surface treatment of magnetic fine particles that can be used in the present invention include a silane coupling agent and a titanium coupling agent. More preferably used is a silane coupling agent, which is represented by the formula (2).

[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a vinyl group, an epoxy group, an acrylic group, or a methacryl group, and n represents 1 to 3] Indicates an integer. However, m + n = 4. ]

As a silane coupling agent shown by Formula (2), the following are mentioned, for example. Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyl Diethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxy Silane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, n-butyltrimethoxysilane, isobutyl Limethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, hydroxypropyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane and the like.
Among these, from the viewpoint of imparting high hydrophobicity to the magnetic fine particles, it is preferable to use an alkyltrialkoxysilane coupling agent represented by the formula (3).

[Wherein, p represents an integer of 2 to 20, and q represents an integer of 1 to 3. ]
If p in the formula (3) is 2 or more, hydrophobicity can be sufficiently imparted to the magnetic fine particles, and if p is 20 or less, the coalescence between the magnetic fine particles is not increased, which is preferable. Furthermore, when q is 3 or less, the reactivity of the silane coupling agent is not lowered and the hydrophobicity is sufficiently performed. Therefore, in the formula, p represents an integer of 2 to 20 (more preferably, an integer of 3 to 15), and q represents an integer of 1 to 3 (more preferably, an integer of 1 or 2). It is preferable to use a silane coupling agent.

When using the said silane coupling agent, it is possible to process independently or to process in combination of several types. When using several types together, you may process separately with each coupling agent, and may process simultaneously.
In the method for producing toner particles of the suspension polymerization method, a known charge control agent, conductivity imparting agent, lubricant, abrasive, etc. may be added in addition to the above-described materials.

In the toner particles of the suspension polymerization method, these additives are uniformly dissolved or dispersed to form a polymerizable monomer composition. Thereafter, the polymerizable monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer using an appropriate stirrer, and if necessary, an aromatic solvent and a polymerization initiator are added to perform a polymerization reaction. To obtain toner particles having a desired particle diameter.
After the polymerization of the toner particles, filtration, washing and drying are performed by a known method, and the inorganic fine particles are mixed and adhered to the surface to obtain a toner.

Next, the inorganic fine particles that can be used in the present invention will be described in detail.
The inorganic fine powder of the present invention contains Group 2 titanate fine particles A and silica fine particles B, and other known ones can be used in combination. The inorganic fine particles that can be used in combination are preferably silica fine particles such as titania fine particles, wet-processed silica, and dry-process silica, and inorganic particles obtained by subjecting the silica to surface treatment with a silane coupling agent, a titanium coupling agent, or silicone oil. Fine particles. The inorganic fine particles subjected to the surface treatment preferably have a degree of hydrophobicity of 30 or more and 98 or less titrated by a methanol titration test.

As the Group 2 titanate fine particles A that can be used in the present invention, known fine particles can be used, but those having a perovskite crystal structure are preferable. Among the perovskite inorganic fine powders, more preferable are strontium titanate, barium titanate, and calcium titanate, and among them, strontium titanate is more preferable.
Inorganic fine particles of perovskite-type crystals are prepared by adding strontium hydroxide to a titania sol dispersion obtained by adjusting the pH of a hydrous titanium oxide slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate. It can be synthesized by heating to temperature. By setting the pH of the hydrous titanium oxide slurry to 0.5 to 1.0, a titania sol having good crystallinity and particle size can be obtained.

  For the purpose of removing ions adsorbed on the titania sol particles, it is preferable to add an alkaline substance such as sodium hydroxide to the dispersion of the titania sol. At this time, it is preferable that the pH of the slurry is not 7 or higher so that sodium ions and the like are not adsorbed on the surface of the hydrous titanium oxide. The reaction temperature is preferably about 60 ° C to 100 ° C. In order to obtain a desired particle size distribution, the rate of temperature rise is preferably 30 ° C / hour or less, and the reaction time is preferably 3 to 7 hours. .

In order to confirm that the crystal structure of the inorganic fine particles is a perovskite type (face-centered cubic lattice composed of three different elements), it can be confirmed by performing X-ray diffraction measurement.
Further, the inorganic fine particles are preferably subjected to surface treatment from the viewpoint of excellent control of the triboelectric charge polarity and the triboelectric charge amount depending on the environment in consideration of development characteristics.
Examples of the surface treatment agent include a treatment agent such as a coupling agent, silicone oil, and fatty acid metal salt.

By performing surface treatment, for example, in the case of a coupling agent that is a compound having a hydrophilic group and a hydrophobic group, the hydrophilic group side covers the surface of the inorganic fine powder so that the hydrophobic group side becomes the outer side. Processing is performed, and fluctuations in the triboelectric charge amount due to the environment can be suppressed. Further, the triboelectric charge amount can be easily controlled by a coupling agent into which a functional group such as an amino group (—NH ₂ ) or fluorine is introduced.
Further, in the case of the surface treatment agent as described above, since the surface treatment at the molecular level is performed, the shape of the inorganic fine powder is hardly changed, and the scraping force by the shape of a roughly cubic or rectangular parallelepiped is maintained. More preferred.

Examples of coupling agents include titanate-based, aluminum-based, and silane-based coupling agents. Examples of the fatty acid metal salt include zinc stearate, sodium stearate, calcium stearate, zinc laurate, aluminum stearate, magnesium stearate and the like, and the same effect can be obtained with stearic acid which is a fatty acid.
Examples of the processing method include the following.
Dissolve and disperse the surface treatment agent to be treated in a solvent, add an inorganic fine powder therein, remove the solvent while stirring, a wet method, a coupling agent, a fatty acid metal salt and an inorganic fine powder A dry method in which the components are directly mixed and treated with stirring.
Further, regarding the surface treatment, it is not necessary to completely treat and coat the inorganic fine powder, and the inorganic fine powder may be exposed as long as the effect is obtained. That is, the surface treatment may be formed discontinuously.

As silica fine particles B that can be used in the present invention, any of dry silica and known wet silica can be used. In the present invention, wet silica produced by a sol-gel method is preferred.
Below, the manufacturing method of the silica fine particle by a sol-gel method is demonstrated.
First, a silica sol suspension is obtained by hydrolyzing and condensing alkoxysilane with a catalyst in an organic solvent in which water is present. Then, the solvent is removed from the silica sol suspension and dried to obtain silica fine particles.
The silica fine particles thus obtained are usually hydrophilic and have many surface silanol groups. Therefore, when used as an external additive for toner, the silica fine particles are preferably subjected to a hydrophobic treatment on the surface.

Hydrophobic treatment methods include removing the solvent from the silica sol suspension and drying it, followed by treatment with the hydrophobizing agent, and adding the hydrophobizing agent directly to the silica sol suspension. The method of processing simultaneously with drying is mentioned. From the viewpoint of controlling the half-value width of the particle size distribution and controlling the saturated water adsorption amount, a method of directly adding a hydrophobizing agent to the silica sol suspension is preferable. Hydrophobic treatment in suspension allows the sol-gel silica to remain in a monodispersed state, making it possible to apply a hydrophobization treatment, so that agglomerates are less likely to form after drying and a uniform coating is possible. .
Further, the pH of the silica sol suspension is more preferably acidic. By making the suspension acidic, the reactivity with the hydrophobizing agent is increased, and a stronger and more uniform hydrophobizing treatment can be performed.

Examples of the hydrophobizing agent include the following.
γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) γ -Aminopropyltrimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, phenyl Trimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, methyltriethoxysilane, butyltriethoxysilane, hexyltriethoxysilane, octyl lithoate Xylsilane, decyltriethoxysilane, dodecyltriethoxysilane, phenyltriethoxysilane, o-methylphenyltriethoxysilane, p-methylphenyltriethoxysilane.

Further, the silica fine particles B may be subjected to a pulverization treatment in order to facilitate the monodispersion of the silica fine particles B on the toner particle surfaces or to exhibit a stable spacer effect.
Silica fine particles B used in the present invention preferably have an apparent density of 150 g / L or more and 300 g / L or less. The apparent density of the silica fine particles B being in the above range indicates that the silica fine particles B are difficult to be densely packed and exist with a lot of air between the fine particles, and the apparent density is very low. For this reason, the mixing property of the toner particles and the silica fine particles B is improved during the external addition step, and a uniform coating state is easily obtained. Further, this phenomenon is more remarkable when the aspect ratio of the toner particles is high, and the coating uniformity tends to be higher. As a result, the toners of the externally added toners approach a point contact state, so that the adhesion between the two particles tends to decrease.

  Means for controlling the apparent density of the silica fine particles B within the above range include adjusting the strength of the hydrophobization treatment in the silica sol suspension or the crushing treatment after the hydrophobization treatment, and the amount of the hydrophobization treatment. Can be mentioned. By performing a uniform hydrophobization treatment, relatively large aggregates themselves can be reduced. Alternatively, by adjusting the strength of the crushing treatment, relatively large aggregates contained in the silica fine particles after drying can be loosened into relatively small secondary particles, and the apparent density can be reduced. is there.

In the present invention, what is called dry process silica or fumed silica is preferably used in combination with the inorganic fine particles. For example, a thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen is used, and the basic reaction formula is as follows.
SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

In this production process, it is possible to obtain composite fine particles of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride or titanium chloride together with silicon halogen compounds.
The particle diameter of the silica fine particles that may be used in the present invention is such that the number average particle diameter (D1) of the primary particles is 5 nm or more and 20 nm or less from the viewpoint of imparting fluidity and ensuring a uniform dispersion state on the toner surface. Is preferred.

Further, the silica fine particles produced by vapor phase oxidation of the silicon halogen compound are more preferably treated silica fine particles having a hydrophobic surface. The treated silica fine particles are particularly preferably those obtained by treating the silica fine particles so that the degree of hydrophobicity measured by a methanol titration test is in the range of 30 to 98.
Examples of the hydrophobic treatment method include a method of chemically treating with an organosilicon compound and / or silicone oil that reacts or physically adsorbs with silica fine particles. A preferred method is a method of chemically treating silica fine particles produced by vapor phase oxidation of a silicon halogen compound with an organosilicon compound.

The following are mentioned as said organosilicon compound.
Hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyl Trichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldi Siloxane, 1,3-divirtetramethyldisiloxane, 1,3-diphenyltetramethyldishiro Xylene and dimethylpolysiloxane having 2 to 12 siloxane units per molecule and one hydroxy group in the terminal Si unit. These are used alone or in a mixture of two or more.

In addition, the following compounds having a nitrogen atom may be used alone or in combination.
Aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, monobutylaminopropyltrimethoxysilane, dioctylamino Silane coupling agents such as propyldimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxysilyl-γ-propylbenzylamine. A preferred silane coupling agent is hexamethyldisilazane (HMDS).

The silicone oil preferably has a kinematic viscosity at 25 ° C. of 0.5 mm ² / sec to 10,000 mm ² / sec, more preferably 1 mm ² / sec to 1,000 mm ² / sec, more preferably 10mm ² / sec or more 200mm ² / s is less than or equal to. Specific examples include dimethyl silicone oil, methyl fell silicone oil, α-methyl styrene modified silicone oil, chlorophenyl silicone oil, and fluorine modified silicone oil.
Examples of the silicone oil treatment method include the following.
A method of directly mixing silica fine particles treated with a silane coupling agent and silicone oil using a mixer such as a Henschel mixer;
・ A method of spraying silicone oil onto silica fine particles as a base;
A method in which silicone oil is dissolved or dispersed in a suitable solvent, and then silica fine particles are added and mixed to remove the solvent.

The silica fine particles treated with silicone oil are more preferably heated to 200 ° C. or higher (more preferably 250 ° C. or higher) in an inert gas to stabilize the surface coating after the silicone oil treatment.
The treatment amount of the silicone oil is preferably 1 part by weight to 40 parts by weight and more preferably 3 parts by weight to 35 parts by weight with respect to 100 parts by weight of the silica fine particles from the viewpoint that good hydrophobicity is easily obtained.

Next, an image forming apparatus using the image forming method of the present invention will be described in detail.
FIG. 1 is a schematic diagram showing an example of an image forming apparatus using the image forming method of the present invention.
The electrostatic latent image carrier 100 is charged by a roller-shaped charging member (charging roller) 117, and is exposed by being irradiated with a laser beam 123 by a laser generator 121. An electrostatic latent image corresponding to the target image is formed on the surface. The electrostatic latent image carrier 100 and the toner carrier 102 rotate in the directions of arrows. The toner is accommodated in the developing device 140 and is supplied to the toner carrier 102 by the toner stirring member 141. The supplied toner is regulated by a nip portion between the toner carrying member 102 and the toner regulating member 142, and is conveyed to a developing region where the electrostatic latent image carrying member 100 and the toner carrying member 102 are opposed to each other for development. The developed toner image is conveyed to a transfer region where the electrostatic latent image carrier 100 and the transfer member 114 are opposed to each other, transferred to the transfer material P, and heated and fixed by the fixing device 126.

  In the charging process according to the present invention, the electrostatic latent image carrier 100 and the charging roller 117 are in contact with each other by forming a contact portion, and a predetermined charging bias is applied to the charging roller 117 to form the electrostatic latent image carrier 100. It is preferable to use a contact charging method in which the surface is charged to a predetermined polarity / potential. By performing contact charging in this manner, stable and uniform charging can be performed, and generation of ozone or the like can be reduced. It is more preferable to use a charging roller 117 that rotates in the same direction as the electrostatic latent image carrier 100 in order to maintain uniform contact with the electrostatic latent image carrier 100 and perform uniform charging.

  As preferable process conditions when using the charging roller, the contact pressure of the charging roller is 4.9 to 490.0 N / m, and the DC voltage or the DC voltage superimposed with the AC voltage can be exemplified. The AC voltage is preferably 0.5 to 5.0 kVpp, the AC frequency is 50 to 5 kHz, and the absolute value of the DC voltage is preferably 400 to 1,700V. The peripheral speed difference of the charging roller relative to the electrostatic latent image carrier is preferably 100 to 150%.

Examples of the material for the charging roller include, but are not limited to, the following materials for the elastic layer.
Rubber material in which conductive materials such as carbon black and metal oxide are dispersed to adjust electrical resistance to ethylene-propylene-diene polyethylene (EPDM), urethane, butadiene acrylonitrile rubber (NBR), silicone rubber, isoprene rubber, etc. Also, these are foamed. In addition, the electrical resistance can be adjusted using an ion conductive material without dispersing the conductive substance or in combination with the conductive substance.
Examples of the core bar used for the charging roller include aluminum and SUS. The charging roller is disposed in pressure contact with a member to be charged as an electrostatic latent image carrier with a predetermined pressing force against elasticity, and is a contact portion between the charging roller and the electrostatic latent image carrier. A charging contact portion is formed.

  In the development process of the present invention, the electrostatic latent image carrier and the toner carrier are in contact with each other by forming a contact portion, and a predetermined developing bias is applied to the toner carrier to apply the toner on the electrostatic latent image carrier. It is preferable to use a contact development method in which the electrostatic latent image is a toner image. By performing such contact development, a high-definition toner image can be obtained, and a high-quality output image can be obtained. Further, since it is contact development, the toner carrier preferably has an elastic layer on the surface of the substrate.

Further, in the development step of the present invention, it is preferable that the developing bias is applied to the toner carrier and the electrostatic latent image on the electrostatic latent image carrier is used as a toner image. A voltage obtained by superimposing an alternating electric field on a DC voltage may be used.
As the waveform of the alternating electric field, a sine wave, a rectangular wave, a triangular wave, or the like can be used as appropriate. Further, it may be a pulse wave formed by periodically turning on / off a DC power source. In this way, a bias that periodically changes its voltage value can be used as the waveform of the alternating electric field.

In the development process of the present invention, when magnetic toner is used, it is necessary to dispose a magnet inside the toner carrier. In this case, the toner carrier preferably has a fixed magnet having multiple poles inside, and preferably has 3 to 10 magnetic poles.
In the developing step of the present invention, it is preferable to regulate the thickness of the toner layer on the toner carrier by the toner regulating member coming into contact with the toner carrier via the toner. In this way, high image quality without fogging can be obtained. As a toner regulating member that abuts on the toner carrier, a regulating blade is generally used and can be suitably used in the present invention.

As the regulation blade, a rubber elastic body such as silicone rubber, urethane rubber, NBR; a synthetic resin elastic body such as polyethylene terephthalate; a metal elastic body such as phosphor bronze plate or SUS plate can be used. There may be. Further, a charge control substance such as resin, rubber, metal oxide, or metal is applied to the contact portion of the toner carrier for the purpose of controlling the chargeability of the toner against an elastic support such as rubber, synthetic resin, or metal elastic body. You may use what was attached to. Among these, it is particularly preferable to attach a resin and rubber to the metal elastic body so as to contact the contact portion of the toner carrier.
As a material of the member to be bonded to the metal elastic body, a material that is easily charged to positive polarity such as urethane rubber, urethane resin, polyamide resin, and nylon resin is preferable.

The base, which is the upper side of the regulating blade, is fixedly held on the developing device side, and the lower side is bent in the forward or reverse direction of the toner carrier against the elastic force of the blade. The surface is brought into contact with an appropriate elastic pressing force.
The contact pressure between the regulating blade and the toner carrier is preferably 1.30 to 245.0 N / m, and more preferably 4.9 to 118.0 N / m, as the linear pressure in the toner carrier bus direction. When the contact pressure is 1.30 N / m or more, uniform application of toner is facilitated, and fogging and scattering are unlikely to occur. When the contact pressure is 245.0 N / m or less, no large pressure is applied to the toner, and the toner is not deteriorated.

  The outer diameter of the toner carrier that carries the toner that can be used in the present invention is preferably 8.0 mm or more and 14.0 mm or less. From the viewpoint of being suitable for miniaturization of the process cartridge, the smaller the outer diameter of the toner carrier, the better. However, the smaller the outer diameter, the more easily the developability is lowered and the fog tends to deteriorate. For this reason, in the toner carrier and the toner used in the present invention, the outer diameter of the toner carrier is preferably 8.0 mm or greater and 14.0 mm or less in order to achieve both size reduction and fog suppression.

The surface roughness of the toner carrier that can be used in the present invention is preferably in the range of 0.3 μm or more and 5.0 μm or less in terms of the centerline average roughness Ra in the standard of JIS B 0601: 1994. More preferably, it is 0.5 μm or more and 4.5 μm or less.
When Ra is 0.3 μm or more and 5.0 μm or less, a sufficient amount of toner can be obtained, the amount of toner on the toner carrying member can be easily regulated, and it is difficult for regulation to occur. It tends to be uniform.

The measurement of the centerline average roughness Ra in the standard of JIS B 0601: 1994 surface roughness of the surface of the toner carrier is performed using Surfcoder SE-3500 manufactured by Kosaka Laboratory. The measurement conditions were 9 points (3 points in the circumferential direction for each of 3 points equally spaced in the axial direction) at a cutoff of 0.8 mm, an evaluation length of 4 mm, and a feed rate of 0.5 mm / sec. And the average value was taken.
To make the surface roughness of the toner carrier in the present invention within the above range, for example, it is possible to change the polishing state of the surface layer of the toner carrier or to add spherical carbon particles, carbon fine particles, graphite, resin fine particles, etc. It becomes.

  As the transfer process of the present invention, a contact transfer system using a transfer member such as a transfer roller is preferable. In the contact transfer method, a toner image is electrostatically transferred to a recording medium while the electrostatic latent image carrier is in contact with a transfer member to which a voltage having a polarity opposite to that of the toner is applied via the recording medium. The contact pressure of the transfer member is preferably 2.9 N / m or more, more preferably 19.6 N / m or more. When the linear pressure as the contact pressure is 2.9 N / m or more, it is difficult for the recording medium to be transported and to cause transfer failure.

As the fixing step of the present invention, a known fixing method can be used. As a heat source when a heated fixing member is used, a halogen heater, an IH heater or the like is preferably used. The shape of the fixing member may be a roller shape or an endless belt.
Next, a method for measuring physical properties relating to the toner and the like used in the present invention will be described in detail. In the examples described later, the physical property values are also measured based on these methods.

<Method for measuring number average particle diameter (D1) of titanate fine particles A and silica fine particles B>
The number average particle diameter (D1) of the primary particles of titanate fine particles A and silica fine particles B is determined by observing the fine particles fixed on the toner with a scanning electron microscope. As a scanning electron microscope, S-4800 (made by Hitachi, Ltd.) is used. The image capturing conditions of S-4800 are as follows.

(Sample preparation)
A thin conductive paste is applied to a sample table (aluminum sample table 15 mm × 6 mm), and toner is sprayed thereon. Further, air is blown to remove excess toner from the sample stage and sufficiently dry. The sample stage is set on the sample holder, and the height of the sample stage is adjusted to 36 mm by the sample height gauge.

(S-4800 observation condition setting)
The number average particle diameter of the fine particles is calculated using an image obtained by observation of the reflected electron image of S-4800. Since the reflected electron image has less charge-up of the silica fine particles than the secondary electron image, the particle size of the fine particles can be measured with high accuracy.
Liquid nitrogen is poured into the anti-contamination trap attached to the S-4800 mirror until it overflows, and is placed for 30 minutes. S-4800 “PCSTEM” is activated and flushing (cleaning of the FE chip as an electron source) is performed. Click the acceleration voltage display part of the control panel on the screen and press the [Flushing] button to open the flushing execution dialog.

Confirm that the flushing intensity is 2 and execute. Confirm that the emission current by flashing is 20-40 μA. Insert the sample holder into the sample chamber of the S-4800 mirror. Press [Origin] on the control panel to move the sample holder to the observation position.
Click the acceleration voltage display section to open the HV setting dialog, and set the acceleration voltage to [0.8 kV] and the emission current to [20 μA]. In the [Basic] tab of the operation panel, set the signal selection to [SE], select [Up (U)] and [+ BSE] for the SE detector, and select [+ BSE] in the selection box on the right. L. A. 100] to select a mode in which observation is performed with a reflected electron image.
Similarly, in the [Basic] tab of the operation panel, the probe current of the electron optical system condition block is set to [Normal], the focus mode is set to [UHR], and the WD is set to [3.0 mm]. Press the [ON] button in the acceleration voltage display section of the control panel to apply the acceleration voltage.

(Calculation of number average particle diameter (D1))
Drag in the magnification display section of the control panel to set the magnification to 100,000 (100k). The focus knob [COARSE] on the operation panel is rotated, and the aperture alignment is adjusted when the focus is achieved to some extent. Click [Align] on the control panel to display the alignment dialog and select [Beam]. The STIGMA / ALIGNMENT knob (X, Y) on the operation panel is rotated to move the displayed beam to the center of the concentric circle.
Next, [Aperture] is selected, and the STIGMA / ALIGNMENT knobs (X, Y) are turned one by one to stop the movement of the image or adjust the movement to the minimum. Close the aperture dialog and focus with auto focus. Repeat this operation two more times to focus.
Thereafter, the average particle size is determined by measuring the particle size of at least 300 fine particles on the surface of the toner particles. Here, since the fine particles may exist as agglomerates depending on the external addition method, the maximum diameter of what can be confirmed as primary particles is obtained, and the obtained maximum diameter is arithmetically averaged to obtain titanate fine particles A and silica. The number average particle diameter (D1) of the primary particles of the fine particles B is obtained.

<Method for Measuring Toner Weight Average Particle Size (D4)>
The weight average particle diameter (D4) of the toner is a precision particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) having a 100 μm aperture tube. Measured with 25,000 effective measurement channels using the dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for setting measurement conditions and analyzing measurement data The measurement data was analyzed and calculated.
As the electrolytic aqueous solution used for the measurement, a special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used. .

Prior to measurement and analysis, the dedicated software was set as follows.
In the “Standard measurement method (SOM) change screen” of the dedicated software, set the total count in the control mode to 50,000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman The value obtained using Coulter Co.) is set. The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1,600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.
In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
1. About 200 mL of the electrolytic aqueous solution is put in a glass 250 mL round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
2. About 30 mL of the electrolytic aqueous solution is put in a glass 100 mL flat bottom beaker, and about 0.3 mL of a diluted solution obtained by diluting “Contaminone N” with ion-exchanged water 3 times as a dispersant is added thereto.
Contaminone N: 10% by weight aqueous solution of neutral detergent for pH 7 precision measuring instrument cleaning, made of nonionic surfactant, anionic surfactant and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.

3. Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and a predetermined amount of ion-exchanged water is placed in the water tank of an ultrasonic disperser with an electric output of 120 W, and the contamination N About 2 mL.
Ultrasonic disperser: Ultrasonic Dispersion System Tetora 150 (manufactured by Nikka Ki Bios Co., Ltd.).
4). 2. Is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.

5. 4. above. In the state where the electrolytic aqueous solution in the beaker is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
6). The above 1. installed in the sample stand. To the round bottom beaker, the electrolyte solution of 5. above in which the toner is dispersed is dropped using a pipette, and the measured concentration is adjusted to about 5%. The measurement is performed until the number of measured particles reaches 50,000.
7). The measurement data is analyzed with the dedicated software attached to the apparatus, and each average particle size is calculated. The “arithmetic diameter” on the analysis / volume statistics screen when graph / volume% is set in the dedicated software is the weight average particle diameter D4.

<Measurement method of fixing rate of titanate fine particles A and silica fine particles B>
(Sample preparation)
Toner before release: Each toner prepared in Examples described later was used as it was.
Toner after freeing: Weigh 20 g of “Contaminone N” (2% by weight aqueous solution of neutral detergent for pH 7 precision measuring instrument cleaning consisting of nonionic surfactant, anionic surfactant and organic builder) into a 50 mL vial. And mixed with 1 g of toner. Set to “KM Shaker” (model: V.SX) manufactured by Iwaki Sangyo Co., Ltd., set speed to 50 and shake for 30 seconds. Thereafter, the toner and the aqueous solution are separated by a centrifugal separator (1,000 rpm for 5 minutes). The supernatant liquid is separated, and the precipitated toner is dried by vacuum drying.

External additive-removed toner: The external additive-removed toner means a state in which an external additive that can be liberated in this test is removed. In the sample preparation method, the toner is put in a solvent that does not dissolve the toner, such as isopropanol, and vibration is applied for 10 minutes with an ultrasonic cleaner. Thereafter, the toner and the solution are separated by a centrifugal separator (1,000 rpm for 5 minutes). The supernatant liquid is separated, and the precipitated toner is dried by vacuum drying.
By using the intensity of the Group 2 element and the intensity of the Si element by wavelength dispersive X-ray fluorescence analysis (XRF) for the samples before and after the removal of the free external additive, the Group 2 titanate fine particles A and The silica fine particles B were quantified to determine how much they were fixed. In the determination of the silica fine particles B, other silica fine particles are also used in the examples described later. However, in this measurement, the measurement was performed under the condition that the other silica fine particles were not forcibly separated.

(I) Examples of equipment used X-ray fluorescence analyzer 3080 (Rigaku Corporation)
Sample press molding machine MAEKAWA Testing Machine (manufactured by MFG Co, LTD)
(Ii) Measurement conditions Measurement potential, voltage 50 kV, 50 to 70 mA
2θ angle a
Crystal plate LiF
Measurement time 60 seconds (iii) Regarding the method for calculating the fixing rate from toner particles First, the element strengths of the pre-release toner, the post-release toner and the external additive-removed toner are determined by the above method. Thereafter, the liberation rate is calculated based on the following formula.
Fixing rate of titanate fine particles A = (strength of second group element of toner after release-strength of second group element of toner after external additive removal) / (strength of second group element of toner before liberation-external addition) Strength of group 2 element of the agent removing toner) × 100
Fixing rate of silica fine particles B = (strength of Si element of toner after release−strength of Si element of toner after removal of external additive) / (strength of Si element of toner before release−strength of Si element of toner after removal of external additive) ) × 100

<Measuring method of half width of particle diameter of silica fine particle B>
The full width at half maximum (full width at half maximum) of the maximum peak in the weight-based particle size distribution curve of the silica fine particles B is CPS Instruments Inc. The measurement is performed using a disk centrifugal particle size distribution analyzer DC24,000. The measuring method is shown below.
(For magnetic toner)
First, 0.5 mg of Triton-X100 (manufactured by Kishida Chemical Co., Ltd.) is added to 100 g of ion-exchanged water to prepare a dispersion medium. 1 g of toner is added to 9 g of this dispersion medium, and dispersed for 5 minutes by an ultrasonic disperser. Thereafter, the toner particles are constrained using a neodymium magnet to produce a supernatant. Next, a syringe dedicated to a measuring device manufactured by CPS is attached to the tip of an all plastic disposable syringe (Tokyo Glass Instrument Co., Ltd.) equipped with a syringe filter (diameter: 13 mm / pore diameter 0.45 μm) (manufactured by Advantech Toyo Co., Ltd.). Attach a needle and collect 0.1 mL of supernatant. The supernatant liquid collected by the syringe is injected into a disk centrifugal particle size distribution measuring apparatus DC24,000, and the half width (full width at half maximum) of the maximum peak in the weight-based particle size distribution curve of the silica fine particles B is measured.

Details of the measurement method are as follows.
First, the disk is rotated at 24,000 rpm with a Motor Control on the CPS software. Then, the following conditions are set from Procedure Definitions.
(1) Sample parameter
・ Maximum Diameter: 0.5μm
・ Minimum Diameter: 0.05μm
・ Particle Density: 2.0-2.2 g / mL (adjust as appropriate depending on the sample)
-Particle Refractive Index: 1.43
・ Particle Absorption: 0K
・ Non-Sphericity Factor: 1.1
(2) Calibration Standard Parameters
・ Peak Diameter: 0.226μm
・ Half Height Peak Width: 0.1 μm
・ Particle Density: 1.389 g / mL
・ Fluid Density: 1.059g / mL
-Fluid Refractive Index: 1.369
Fluid Fluidity: 1.1 cps

After setting the above conditions, CPS Instruments Inc. Using an auto gradient maker AG300, a density gradient solution of 8 mass% sucrose aqueous solution and 24 mass% sucrose aqueous solution is prepared, and 15 mL is injected into the measurement container.
After the injection, in order to prevent evaporation of the density gradient solution, 1.0 mL of dodecane (manufactured by Kishida Chemical Co., Ltd.) is injected to form an oil film, and the apparatus waits for 30 minutes or more to stabilize the apparatus.
After waiting, calibration standard particles (weight-based center particle size: 0.226 μm) are injected into the measuring apparatus with a 0.1 mL syringe, and calibration is performed. Thereafter, the collected supernatant is injected into the apparatus, and the half width of the maximum peak in the weight-based particle size distribution curve is measured.
FIG. 3 shows an example of data obtained when actually measured. As shown in FIG. 3, the half-value width (full width at half maximum) of the maximum peak obtained at a particle size of 80 nm to 200 nm in the weight-based particle size distribution curve is the full width at half maximum of the maximum peak in the weight-based particle size distribution curve of silica fine particles B. (Full width).

(For non-magnetic toner)
First, 0.5 mg of Triton-X100 (manufactured by Kishida Chemical Co., Ltd.) is added to 100 g of ion-exchanged water to prepare a dispersion medium. To 9.4 g of this dispersion medium, 0.6 g of toner is added and dispersed with an ultrasonic disperser for 5 minutes. Thereafter, a syringe needle dedicated to a measuring device manufactured by CPS is attached to the tip of an all plastic disposable syringe (Tokyo Glass Instrument Co., Ltd.) equipped with a syringe filter (diameter: 13 mm / pore diameter 0.45 μm) (manufactured by Advantech Toyo Co., Ltd.). And 0.1 mL of the supernatant is collected. The supernatant collected with a syringe is injected into a disk centrifugal particle size distribution measuring apparatus DC24000, and the half-value width of the maximum peak in the weight-based particle size distribution curve of the silica fine particles B is measured. The details of the measurement method are as described above.

<Measurement method of toner aspect ratio>
The aspect ratio of the toner was measured with a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during calibration.
A specific measurement method is as follows.
First, about 20 mL of ion-exchanged water from which impure solids and the like are previously removed is placed in a glass container. As a dispersant, “Contaminone N” (a nonionic surfactant, an anionic surfactant, a 10% by weight aqueous solution of a neutral detergent for washing a pH 7 precision measuring instrument comprising an organic builder, Wako Pure Chemical Industries, Ltd. About 0.2 mL of a diluted solution obtained by diluting (made in ()) with ion-exchanged water about 3 times by mass is added. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (for example, “VS-150” (manufactured by Vervo Crea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. A predetermined amount of ion-exchanged water is placed in the water tank, and about 2 mL of the contamination N is added to the water tank.

  For the measurement, the flow type particle image analyzer equipped with “LUCPLFLN” (magnification 20 ×, numerical aperture 0.40) as an objective lens was used, and particle sheath “PSE-900A” (Sysmex Corporation) was used as the sheath liquid. Made). The dispersion prepared in accordance with the above procedure is introduced into the flow type particle image analyzer, and 2,000 toner particles are measured in the HPF measurement mode and in the total count mode. Then, the binarization threshold at the time of particle analysis was set to 85%, the analysis particle diameter was limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm, and the toner aspect ratio was determined.

In measurement, automatic focus adjustment is performed using standard latex particles before the measurement is started. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.
Standard latex particles: for example, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5100A” manufactured by Duke Scientific, diluted with ion-exchanged water.
In the examples of the present application, a flow-type particle image analyzer that has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, was used. Measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle diameter was limited to a circle equivalent diameter of 1.977 μm or more and less than 39.54 μm.

<Method for measuring adhesion between two particles of toner>
To measure the adhesion between the two particles of the toner, Aggrobot manufactured by Hosokawa Micron Corporation is used. A specific measurement method is as follows.
(For magnetic toner)
In a cylindrical cell (upper cell 251 and lower cell 252) divided into upper and lower parts shown in FIG. 2A, 9.2 g of toner is filled in an environment of a temperature of 23 ° C. and a relative humidity of 50%. Thereafter, the compression rod 253 is lowered at a speed of 0.1 mm / second to apply a vertical load of 78.5 N or 157.0 N to form a compacted toner layer.
Thereafter, as shown in FIG. 2B, the upper cell 251 is lifted by the spring 254 at a speed of 0.4 mm / second to pull the toner layer, and the maximum tensile breaking force when the toner layer is broken is Calculate the adhesion.
The cylindrical cell has an inner diameter of 25 mm and a height of 37.5 mm.

(For non-magnetic toner)
In a cylindrical cell (upper cell 251 and lower cell 252) divided into upper and lower parts shown in FIG. 2A, 7.7 g of toner is filled in an environment of a temperature of 23 ° C. and a relative humidity of 50%. The adhesion between the two particles is calculated in the same manner as in the case of the magnetic toner except for the toner filling amount.

<Measurement of softening point of polyester resin>
The softening point of the resin is measured by using a constant load extrusion type capillary rheometer “Flow Characteristic Evaluation Device Flow Tester CFT-500D” (manufactured by Shimadzu Corporation) according to the manual attached to the device. In this device, while applying a constant load from the top of the measurement sample with the piston, the measurement sample filled in the cylinder is heated and melted, and the melted measurement sample is pushed out from the die at the bottom of the cylinder, and the piston drop amount at this time A flow curve showing the relationship between temperature and temperature can be obtained.

  The “melting temperature in the 1/2 method” described in the manual attached to the “flow characteristic evaluation device Flow Tester CFT-500D” is defined as the softening point. The melting temperature in the 1/2 method is calculated as follows. First, ½ of the difference between the piston lowering amount Smax at the time when the outflow ends and the piston lowering amount Smin at the time when the outflow starts is obtained (this is X. X = (Smax−Smin) / 2). And the temperature of the flow curve when the amount of descending piston is the sum of X and Smin in the flow curve is the melting temperature in the 1/2 method.

About 1.0 g of the measurement sample is compressed at about 10 MPa at a temperature of 25 ° C. using a tablet molding compressor (for example, NT-100H, manufactured by NP System Co., Ltd.) for about 60 seconds. A cylindrical shape having a diameter of about 8 mm is used.
The measurement conditions of CFT-500D are as follows.
Test mode: Temperature rising method Temperature rising rate: 4 ° C / min Start temperature: 50 ° C
Achieving temperature: 200 ° C

Examples are shown below. However, the present invention is not limited to the following examples.
First, a method for producing the Group 2 titanate fine particles A and the silica fine particles B will be described in detail.
<Production Example of Titanate Fine Particles A-1 to A-3>
The hydrous titanium oxide obtained by hydrolyzing the aqueous titanyl sulfate solution was washed with pure water until the electric conductivity of the filtrate reached 2,200 μS / cm. NaOH was added to the hydrous titanium oxide slurry, and the sulfate radical adsorbed was washed with SO ₃ until it became 0.24%. Next, hydrochloric acid was added to the hydrous titanium oxide slurry to adjust the pH of the slurry to 1.0 to obtain a titania sol dispersion. NaOH was added to the titania sol dispersion, the pH of the dispersion was 6.0, and the supernatant was washed by decantation with pure water until the electrical conductivity of the supernatant reached 120 μS / cm.

533 g (0.6 mol) of metatitanic acid having a moisture content of 91% obtained as described above was put into a SUS reaction vessel, and nitrogen gas was blown into the vessel and left for 20 minutes to replace the inside of the reaction vessel with nitrogen gas. 183.6 g (0.66 mol) of Sr (OH) ₂ .8H ₂ O (purity 95.5%) was added, and pure water was further added to add 0.3 mol / liter (in terms of SrTiO ₃ ), SrO / TiO _2. A slurry with a molar ratio of 1.10 was prepared.

  The slurry was heated to 90 ° C. in a nitrogen atmosphere to carry out the reaction. After the reaction, the reaction solution is cooled to 40 ° C., the supernatant is removed under a nitrogen atmosphere, and the operation of adding 2.5 liters of pure water and decanting is repeated twice, followed by filtration with Nutsche. It was. The obtained cake was dried in the atmosphere at 110 ° C. for 4 hours to obtain strontium titanate fine particles having a number average particle diameter (D1) of 120 nm and a primary particle shape of cubic and / or rectangular parallelepiped.

Subsequently, 2.5 liters of pure water was added to the obtained strontium titanate fine particles to further adjust the pH to about 3.5. After the adjustment, the reactor was heated to 75 ° C., and a solution obtained by dissolving 8.8 g of octyltriethoxysilane in 220 mL of isopropyl alcohol was added dropwise while stirring the reactor. After the dropwise addition, stirring was continued for 5 hours.
After completion of stirring, the mixture was cooled to room temperature and filtered. The filtrate was washed with ion-exchanged water and then dried by heating at 120 ° C. overnight. Then, the crushing process was performed and the titanate fine particle A-1 which processed the surface of the strontium titanate fine particle with octyl triethoxysilane was obtained.
The crystal structure of the titanate fine particles A-1 was confirmed to be a perovskite type by X-ray diffraction measurement.
Moreover, the particle size was controlled by adjusting the reaction time after raising the temperature of the slurry to 90 ° C. to obtain titanate fine particles A-2 and A-3 having the desired particle size.
X-ray diffraction measurement was performed to confirm that the crystal structures of the titanate fine particles A-2 and A-3 were of the perovskite type.

<Example of production of titanate fine particles A-4>
1.0 liter of a 2.5 mol / L titanium tetrachloride aqueous solution and 1.0 liter of ion-exchanged water in terms of TiO ₂ were placed in a 5.0 liter four-necked flask while cooling. While stirring, 28% by mass of ammonia water was added dropwise to adjust the pH to about 7.0. The obtained precipitate of titanium oxide hydrate was filtered with a suction filter and washed with pure water until the electric conductivity of the filtrate reached 20 μS / cm to obtain a cake. Next, an amount of 100 g in terms of TiO ₂ was separated from the cake, and the cake and 1.0 liter of ion-exchanged water were placed in a beaker to obtain a suspension. Next, the suspension and 592 g of barium hydroxide (Ba (OH) ₂ .8H ₂ O) (Ba / Ti molar ratio = 1.5) were placed in a 3.0 liter autoclave and heated to 150 ° C. The heat treatment was performed for 1 hour. Subsequently, the obtained product was filtered and washed with a suction filter, and dried at a temperature of 105 ° C. The obtained dried product was baked at 500 ° C. for 1 hour and pulverized to obtain barium titanate fine particles having a number average particle size (D1) of 120 nm and a primary particle shape of cubic and / or cuboid.

Subsequently, 2.5 liters of pure water was added to the obtained barium titanate fine particles to further adjust the pH to about 3.5. After the adjustment, the reactor was heated to 75 ° C., and a solution obtained by dissolving 8.8 g of octyltriethoxysilane in 220 mL of isopropyl alcohol was added dropwise while stirring the reactor. After the dropwise addition, stirring was continued for 5 hours.
After completion of stirring, the mixture was cooled to room temperature and filtered. The filtrate was washed with ion-exchanged water and then dried by heating at 120 ° C. overnight. Thereafter, crushing treatment was performed to obtain titanate fine particles A-4 in which the surface of the barium titanate fine particles was treated with octyltriethoxysilane.
It was confirmed by X-ray diffraction measurement that the crystal structure of the titanate fine particles A-4 was a perovskite type.

<Example of production of titanate fine particles A-5>
600 g of strontium carbonate and 320 g of titanium oxide were dry mixed in a ball mill for 8 hours and then filtered and dried. This mixture was molded at a pressure of 5 kg / cm ² and calcined at a temperature of 1,100 ° C. for 8 hours. Thereafter, it was mechanically pulverized to obtain granular strontium titanate fine particles having a number average particle diameter (D1) of 120 nm.
Subsequently, 2.5 liters of pure water was added to the obtained strontium titanate fine particles to further adjust the pH to about 3.5. After the adjustment, the reactor was heated to 75 ° C., and a solution obtained by dissolving 8.8 g of octyltriethoxysilane in 220 mL of isopropyl alcohol was added dropwise while stirring the reactor. After the dropwise addition, stirring was continued for 5 hours.
After completion of stirring, the mixture was cooled to room temperature and filtered. The filtrate was washed with ion-exchanged water and then dried by heating at 120 ° C. overnight. Thereafter, crushing treatment was performed to obtain titanate fine particles A-5 in which the surface of strontium titanate fine particles was treated with octyltriethoxysilane.

<Example of production of titanate fine particles A-6>
600 g of strontium carbonate and 320 g of titanium oxide were dry mixed in a ball mill for 8 hours and then filtered and dried. This mixture was molded at a pressure of 5 kg / cm ² and calcined at a temperature of 1,100 ° C. for 8 hours. Thereafter, it was mechanically pulverized to obtain granular strontium titanate fine particles having a number average particle diameter of 120 nm.
Subsequently, 100 parts of strontium titanate fine particles were added to a sodium stearate aqueous solution (7 parts of sodium stearate and 100 parts of water) which is a fatty acid metal salt. While stirring, an aqueous aluminum sulfate solution was dropped, and aluminum stearate was precipitated and adsorbed on the surface of the strontium titanate fine particles to obtain titanate fine particles A-6 treated with stearic acid.

<Production Example of Silica Fine Particles B-1 to B-3>
In a 3 L glass reactor equipped with a stirrer, a dropping funnel and a thermometer, 687.9 g of methanol, 42.0 g of pure water and 47.1 g of 28 mass% ammonia water were added and mixed. The obtained solution was adjusted so as to have a temperature of 35 ° C., and while stirring, 1,100.0 g (7.23 mol) of tetramethoxysilane and 395.2 g of 5.4% by mass aqueous ammonia started to be added simultaneously. . Tetramethoxysilane was added dropwise over 5 hours and ammonia water was added over 4 hours. Even after the dropping was completed, the mixture was further stirred for 0.2 hours for hydrolysis to obtain a suspension of hydrophilic and spherical sol-gel silica fine particles.
Thereafter, the pH of the prepared suspension was adjusted to about 3.5. After the adjustment, the reactor was heated to 75 ° C., and a solution obtained by dissolving 8.8 g of octyltriethoxysilane in 220 mL of isopropyl alcohol was added dropwise while stirring the reactor. After the dropwise addition, stirring was continued for 5 hours.
After completion of stirring, the mixture was cooled to room temperature and filtered. The filtrate was washed with ion-exchanged water and then dried by heating at 120 ° C. overnight. Then, the crushing process was performed and the silica fine particle B-1 whose number average particle diameter (D1) is 120 nm was obtained.
Moreover, the particle diameter was controlled by adjusting the dropping time of the tetramethoxysilane and the ammonia water, and silica fine particles B-2 and B-3 having the target particle diameter were obtained.

<Production Example of Silica Fine Particle B-4>
A suspension of sol-gel silica fine particles was obtained in the same manner as in the production example of silica fine particles B-1.
Next, an ester adapter and a condenser tube were attached to the glass reactor, and the suspension was heated to 65 ° C. to distill off methanol. Thereafter, the same amount of pure water as the distilled methanol was added. This dispersion was sufficiently dried at 80 ° C. under reduced pressure. The obtained silica particles were heated at 400 ° C. for 10 minutes in a thermostatic bath. The said process was implemented 20 times and the crushing process was performed after that.
Subsequently, 2.5 liters of pure water was added to the obtained silica fine particles to further adjust the pH to about 3.5. After the adjustment, the reactor was heated to 75 ° C., and a solution obtained by dissolving 8.8 g of octyltriethoxysilane in 220 mL of isopropyl alcohol was added dropwise while stirring the reactor. After the dropwise addition, stirring was continued for 5 hours.
After completion of stirring, the mixture was cooled to room temperature and filtered. The filtrate was washed with ion-exchanged water and then dried by heating at 120 ° C. overnight. Then, the crushing process was performed and the silica fine particle B-4 whose number average particle diameter (D1) is 120 nm was obtained.

<Production Example of Silica Fine Particle B-5>
A suspension of sol-gel silica fine particles was obtained in the same manner as in the production example of silica fine particles B-1.
Next, an ester adapter and a condenser tube were attached to the glass reactor, and the suspension was heated to 65 ° C. to distill off methanol. Thereafter, the same amount of pure water as the distilled methanol was added. This dispersion was sufficiently dried at 80 ° C. under reduced pressure. The obtained silica particles were heated at 400 ° C. for 10 minutes in a thermostatic bath. The said process was implemented 20 times and the crushing process was performed after that.

Subsequently, 500 g of silica particles were charged into a polytetrafluoroethylene inner cylinder type stainless steel autoclave having an inner volume of 1,000 mL. After replacing the inside of the autoclave with nitrogen gas, stirring the inside of the autoclave, 0.5 g of HMDS (hexamethyldisilazane) and 0.1 g of pure water are atomized with a two-fluid nozzle to form a uniform silica powder. Sprayed on. After stirring for 30 minutes, the autoclave was sealed and heated at 200 ° C. for 2 hours. Subsequently, the inside of the autoclave was depressurized while being heated and deammoniated to obtain silica fine particles B-5 having a number average particle diameter (D1) of 120 nm.
Next, the toner particles and the toner manufacturing method will be described in detail.

<Example of production of polyester resin 1>
Into a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, a monomer was added at a compounding ratio of 42 mol of terephthalic acid and 58 mol of bisphenol A-propylene oxide (2 mol adduct), and then as a catalyst. 1.5 parts by mass of dibutyltin was added to 100 parts by mass of the total amount of monomers. Next, the temperature was quickly raised to 180 ° C. under normal pressure in a nitrogen atmosphere, and then water was distilled off while heating from 180 ° C. to 210 ° C. at a rate of 10 ° C./hour to perform polycondensation. After reaching the temperature of 210 ° C., the pressure in the reaction vessel was reduced to 5 kPa or less, and polycondensation was performed under the conditions of 210 ° C. and 5 kPa or less to obtain a polyester resin 1. At that time, the polymerization time was adjusted so that the softening point of the obtained polyester resin 1 was 120 ° C.

<Production example of magnetic body 1>
The following materials were mixed in an aqueous ferrous sulfate solution to prepare an aqueous solution containing ferrous hydroxide.
1.00 to 1.10 equivalent of caustic soda solution with respect to iron element,
· The amount of _P 2 _O 5 to an iron element to be 0.15% by mass in terms of phosphorus,
-SiO _{2 in an} amount of 0.50% by mass in terms of silicon element with respect to iron element
The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.
Subsequently, the ferrous sulfate aqueous solution was added to this slurry liquid so that it might become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda). Thereafter, the slurry liquid was maintained at pH 7.6, and an oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the water-containing slurry was once taken out. At this time, a small amount of water-containing sample was collected and the water content was measured. Next, this water-containing sample is put into another aqueous medium without being dried, stirred and redispersed with a pin mill while circulating the slurry, and the pH of the redispersed liquid is adjusted to about 4.8. Then, 1.6 parts of n-hexyltrimethoxysilane coupling agent was added to 100 parts of magnetic iron oxide with stirring (the amount of magnetic iron oxide was calculated as a value obtained by subtracting the water content from the water-containing sample), and water was added. Decomposition was performed. Thereafter, the mixture was sufficiently stirred, and the dispersion was subjected to surface treatment at a pH of 8.6. The produced hydrophobic magnetic material is filtered with a filter press, washed with a large amount of water, dried at a temperature of 100 ° C. for 15 minutes, and then at a temperature of 90 ° C. for 30 minutes. A magnetic body 1 having a diameter of 0.21 μm was obtained.

<Production Example of Toner 1>
A toner was manufactured according to the following procedure.
(Preparation of the first aqueous medium)
3.1 parts by mass of sodium phosphate dodecahydrate was added to 342.8 parts by mass of ion-exchanged water, and the mixture was heated to 60 ° C. with stirring using a TK homomixer (manufactured by Primix Industry Co., Ltd.). . Then, the following materials were added and stirring was performed to obtain a first aqueous medium containing the dispersion stabilizer A.
-A calcium chloride aqueous solution in which 1.8 parts by mass of calcium chloride dihydrate is added to 12.7 parts by mass of ion-exchanged water,
-A sodium chloride aqueous solution in which 4.3 parts by mass of sodium chloride is added to 14.5 parts by mass of ion-exchanged water.

(Preparation of polymerizable monomer composition)
Styrene 74.0 parts by mass n-butyl acrylate 26.0 parts by mass 1-6 hexanediol diacrylate 0.5 parts by mass Aluminum salicylate compound (E-101: manufactured by Orient Chemical Co., Ltd.)
0.5 parts by mass / colorant: 65.0 parts by mass of magnetic material 1 / 0.07 parts by mass of polyester resin 1 The above materials were uniformly dispersed and mixed using an attritor (manufactured by Nippon Coke Industries, Ltd.). Thereafter, the mixture was heated to 60 ° C., and 15.0 parts by mass of paraffin wax (maximum endothermic peak temperature in DSC (Differential Scanning Calorimetry) curve: 80 ° C.) was added and mixed, and dissolved to form a polymerizable monomer composition. I got a thing.

(Preparation of second aqueous medium)
0.9 parts by mass of sodium phosphate dodecahydrate was added to 164.7 parts by mass of ion-exchanged water, and the mixture was heated to 60 ° C. with stirring using a paddle stirring blade. Thereafter, a calcium chloride aqueous solution in which 0.5 part by mass of calcium chloride dihydrate was added to 3.8 parts by mass of ion-exchanged water was added, and stirring was continued to obtain a second aqueous medium containing the dispersion stabilizer B.

(Granulation)
Into the first aqueous medium, 7.0 parts by mass of the polymerizable monomer composition and t-butyl peroxypivalate as a polymerization initiator are added and granulated while stirring under the following stirring conditions. A granulation liquid containing droplets of the polymerizable monomer composition was obtained.
Stirring conditions: Stirring was performed at a rotation speed of 12,000 rpm for 10 minutes using a TK homomixer (manufactured by Primix Kogyo Co., Ltd.) in a N ₂ atmosphere at a temperature of 60 ° C.

(Polymerization / distillation / drying)
The granulation liquid was put into the second aqueous medium and reacted at a temperature of 74 ° C. for 3 hours while stirring with a paddle stirring blade. After completion of the reaction, the mixture was distilled at 98 ° C. for 3 hours, and then the suspension was cooled, washed with hydrochloric acid, filtered, and dried to obtain toner particles having a weight average particle diameter (D4) of 8.0 μm. It was.

(External additive mixing)
To 100 parts by mass of the obtained toner particles, the following materials were mixed with Mitsui Henschel mixer (FM-10 model manufactured by Nippon Coke Industries Co., Ltd.) to obtain toner 1. The temperature was adjusted so that the rotation speed of the stirring blade of the Henschel mixer was 4,000 rpm, the mixing time was 7 minutes, and the jacket temperature was 45 ° C.
-Titanate fine particles A-1 0.5 parts by mass-Silica fine particles B-1 0.5 parts by mass-Primary particles surface-treated with 15% by mass of hexamethyldisilazane Hydrophobic silica fine particles having a number average particle diameter of 20 nm 1 .0 parts by mass

  The toner obtained had an aspect ratio of 0.920, Fp (A) of 15 nN, and (Fp (B) -Fp (A)) / Fp (A) of 0.30. Further, the number average particle diameter (D1) of the titanate fine particles A-1 diffused and fixed on the surface of the obtained toner was 120 nm, and the fixing rate of the titanate fine particles A-1 was 65%. The number average particle diameter (D1) of the silica fine particles B-1 was 120 nm, the fixing rate of the silica fine particles B-1 was 75%, and the half width of the particle diameter of the silica fine particles B-1 was 9 nm. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 2>
A toner 2 was obtained in the same manner as in the production example of the toner 1 except that the titanate fine particles A-1 were changed to A-2 and the silica fine particles B-1 were changed to B-2 in the production example of the toner 1. . Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 3>
A toner 3 was obtained in the same manner as in the production example of the toner 1 except that the titanate fine particles A-1 were changed to A-3 and the silica fine particles B-1 were changed to B-3 in the production example of the toner 1. . Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 4>
In the production example of toner 1, toner 4 was obtained in the same manner as in the production example of toner 1 except that the mixing time during external addition was 2 minutes and the jacket temperature was 40 ° C. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 5>
In the production example of toner 1, toner 5 was obtained in the same manner as in the production example of toner 1 except that the mixing time during external addition was 10 minutes and the jacket temperature was 50 ° C. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 6>
A toner 6 was obtained in the same manner as in the production example of the toner 1 except that the titanate fine particles A-1 were changed to A-4 in the production example of the toner 1. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 7>
In the toner 1 production example, the added amount of sodium phosphate dodecahydrate used for preparation of the second aqueous medium was 0.3 parts by mass, and the added part of calcium chloride dihydrate was 0.17 parts by mass. Except for the above, Toner 7 was obtained in the same manner as in Toner 1 Production Example. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 8>
In the production example of toner 1, toner 8 was obtained in the same manner as in the production example of toner 1 except that the second aqueous medium was not used. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 9>
A toner 9 was obtained in the same manner as in the production example of the toner 8 except that the silica fine particle B-1 was changed to B-4 in the production example of the toner 8. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 10>
A toner 10 was obtained in the same manner as in the production example of the toner 9 except that the titanate fine particles A-1 were changed to A-5 in the production example of the toner 9. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 11>
A toner 11 was obtained in the same manner as in the toner 9 production example except that the titanate fine particles A-1 were changed to A-6 in the toner 9 production example. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 12>
A toner 12 was obtained in the same manner as in the production example of the toner 9 except that the titanate fine particles A-1 were changed to A-5 and the silica fine particles B-4 were changed to B-5 in the production example of the toner 9. . Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 13>
A toner 13 was obtained in the same manner as in the production example of the toner 9 except that the titanate fine particles A-1 were changed to A-6 and the silica fine particles B-4 were changed to B-5 in the production example of the toner 9. . Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 14>
A toner was prepared using the following materials.
Polyester resin 1 100 parts by mass Magnetic substance 1 65 parts by mass Paraffin wax (maximum endothermic peak temperature: 80 ° C) 5 parts by mass Aluminum salicylate compound (E-101: manufactured by Orient Chemical Co., Ltd.)
0.5 parts by mass

  The above materials were mixed with a Mitsui Henschel mixer (FM-75 type, manufactured by Nippon Coke Industries Co., Ltd.) and then melt-kneaded with a twin-screw extruder (PCM-30 type, manufactured by Ikegai) set at a temperature of 120 ° C. . The obtained kneaded product was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized toner. The obtained coarsely pulverized toner was finely pulverized using a mechanical pulverizer (T-300 type, manufactured by Freund Turbo). As pulverization conditions, pulverization was performed with the rotational speed of the rotor being 120 s-1.

Next, the obtained finely pulverized product was subjected to surface modification using a surface modification apparatus shown in FIG.
The surface modification apparatus of FIG. 4 will be described below. First, the processed product 200 is introduced into the processed product supply port 202 by the high-pressure air supply nozzle 201, and the processed product 200 is diffused into the processing tank having the cooling jacket 207 using the airflow jet member 203. The diffused processed product 200 is surface-modified by hot air introduced from the hot air supply port 204, further cooled by the cold air introduced from the cold air supply ports 205 and / or 206, and sent to the transfer pipe 208 to be processed. Get.
The conditions at the time of surface modification were as follows: the treated material supply rate was 2.0 kg / hour, the hot air flow rate was 4.5 m ³ / min, the hot air discharge temperature was 220 ° C., the cold air temperature was 3 ° C., and the cold air flow rate was 3.0 m ³ / min. Surface modification was performed. Next, by classifying with a wind classifier (Elbow Jet Lab EJ-L3, manufactured by Nippon Steel Mining Co., Ltd.) using the Coanda effect, fine powder and coarse powder are classified and removed at the same time, and the weight average particle diameter (D4) is 8 1. Toner particles of 1 μm were obtained.

To 100 parts by mass of the obtained toner particles, the following materials were mixed with a Mitsui Henschel mixer (FM-10 model manufactured by Nippon Coke Industries Co., Ltd.) to obtain toner 14. The temperature was adjusted so that the rotation speed of the stirring blade of the Henschel mixer was 4,000 rpm, the mixing time was 7 minutes, and the jacket temperature was 45 ° C.
-Titanate fine particles A-1 0.5 parts by mass-Silica fine particles B-4 0.5 parts by mass-Primary particles surface-treated with 15% by mass of hexamethyldisilazane Hydrophobic silica fine particles having a number average particle diameter of 20 nm 1 .0 parts by mass

<Production Example of Toner 15>
A toner 15 was obtained in the same manner as in the production example of the toner 7 except that in the production example of the toner 7, the magnetic material 1 was changed to 6 parts by mass of carbon black (Printtex 35: manufactured by Degussa). Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 16>
In the production example of toner 8, toner 16 was obtained in the same manner as in the production example of toner 8 except that titanate fine particles A-1 and silica fine particles B-1 were not used. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 17>
In the production example of toner 8, toner 17 was obtained in the same manner as in the production example of toner 8 except that titanate fine particles A-1 were not used. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 18>
In the production example of the toner 8, a toner 18 was obtained in the same manner as in the production example of the toner 8 except that the silica fine particles B-1 were not used. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 19>
In the toner 9 production example, a toner 19 was obtained in the same manner as in the toner 9 production example except that the mixing time for external addition was 2 minutes and the jacket temperature was 23 ° C. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 20>
In the production example of toner 9, toner 20 was obtained in the same manner as in the production example of toner 9 except that the mixing time during external addition was 20 minutes and the jacket temperature was 52 ° C. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 21>
In the toner 9 production example, toner 21 was obtained in the same manner as in the toner 9 production example, except that the rotation speed of the homomixer during granulation was changed to 9,000 rpm. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner 22>
In the toner 14 production example, a toner 22 was obtained in the same manner as in the toner 14 production example, except that the thermal spheronization treatment was not performed. Table 1 shows the physical properties of the obtained toner.

<Production example of toner 23>
In the production example of the toner 15, a toner 23 was obtained in the same manner as in the production example of the toner 15 except that the titanate fine particles A-1 and the silica fine particles B-1 were not used. Table 1 shows the physical properties of the obtained toner.

<Production Example of Toner Carrier 102>
The toner carrier 102 was manufactured by the following procedure.
(Synthesis of isocyanate group-terminated prepolymer)
Under a nitrogen atmosphere, tolylene diisocyanate (TDI) (trade name: Cosmonate T80; manufactured by Mitsui Chemicals, Inc.) 17.7 parts by mass, the following materials were brought to a temperature of 65 ° C. While holding, the solution was gradually dropped.
Polypropylene glycol-based polyol (trade name: Exenol 4030; manufactured by Asahi Glass Co., Ltd.) 100.0 g
After completion of the dropping, the reaction was carried out at a temperature of 65 ° C. for 2 hours. The resulting reaction mixture was cooled to room temperature to obtain an isocyanate group-terminated prepolymer having an isocyanate group content of 3.8% by mass.

(Synthesis of amino compounds)
In a reaction vessel equipped with a stirrer, a thermometer, a reflux tube, a dropping device, and a temperature controller, 100.0 parts by mass (1.67 mol) of ethylenediamine and 100 parts by mass of pure water were heated to 40 ° C. while stirring. did. Next, while maintaining the reaction temperature at 40 ° C. or lower, 425.3 parts by mass (7.35 mol) of propylene oxide was gradually added dropwise over 30 minutes. The reaction was further stirred for 1 hour to obtain a reaction mixture. The obtained reaction mixture was heated under reduced pressure to distill off water, thereby obtaining 426 g of an amino compound.

(Preparation of substrate)
As a substrate, a primer (trade name, DY35-051; manufactured by Toray Dow Corning Co., Ltd.) was applied and baked on a ground aluminum cylindrical tube having an outer diameter of 10 mm (diameter) and an arithmetic average roughness Ra of 0.2 μm.

(Production of elastic roller)
The substrate prepared above was placed in a mold, and an addition type silicone rubber composition in which the following materials were mixed was injected into a cavity formed in the mold.
-100 parts by mass of liquid silicone rubber material (trade name, SE6724A / B; manufactured by Toray Dow Corning Co., Ltd.)
-15 parts by mass of carbon black (trade name, Toka Black # 4300; manufactured by Tokai Carbon Co., Ltd.)
-0.2 parts by mass of silica powder as a heat resistance imparting agent,
-Platinum catalyst 0.1 mass part.
Subsequently, the mold was heated to vulcanize and cure the silicone rubber composition at a temperature of 150 ° C. for 15 minutes. The substrate on which the cured silicone rubber layer was formed on the peripheral surface was removed from the mold, and then the substrate was further heated at a temperature of 180 ° C. for 1 hour to complete the curing reaction of the silicone rubber layer. Thus, an elastic roller having a silicone rubber elastic layer having a film thickness of 0.5 mm and a diameter of 11 mm formed on the outer periphery of the substrate was produced.

(Preparation of surface layer)
The following materials were stirred and mixed as materials for the surface layer.
-Amino compound 34.2 parts by mass,
Carbon black (trade name, MA230; manufactured by Mitsubishi Chemical Corporation) 117.4 parts by mass,
-Urethane resin fine particles (trade name, Art Pearl C-400; manufactured by Negami Kogyo Co., Ltd.)
130.4 parts by mass.
In addition, each mass part is a value with respect to 617.9 mass parts of isocyanate group terminal prepolymers.
Next, MEK (methyl ethyl ketone) was added so that the total solid content ratio was 30% by mass to prepare a coating material for forming a surface layer.
Next, the rubber-free portion of the previously produced elastic roller was masked and stood vertically, rotated at 1,500 rpm, and the paint was applied while lowering the spray gun at 30 mm / sec. Subsequently, the coating layer was cured and dried by heating at a temperature of 180 ° C. for 20 minutes in a hot air drying oven, thereby obtaining a toner carrier 102 having a surface layer having a thickness of about 8 μm on the outer periphery of the elastic layer.

<Example 1>
For image evaluation in the examples, a commercially available laser printer LASERJET PRO P1606 (manufactured by HP) was modified and used.
The process cartridge of the evaluation machine was taken out and the cleaning blade was removed from the cartridge. Then, the toner carrier was changed to the toner carrier 102 and installed so as to be in contact with the photosensitive member for development, and the development bias was modified so that only a direct current was applied so that a bias could be applied from the outside. . The following product toner was extracted, and 120 g of toner 1 was filled. The cartridge was allowed to stand for 24 hours in a high-temperature and high-humidity (H / H) environment at a temperature of 32.5 ° C. and a relative humidity of 80%. As media, talc paper CTM-2 (manufactured by Oji Paper Co., Ltd.) was used, and for image output evaluation, the following evaluation was performed and the following indices were used. The evaluation results are shown in Table 2.

<Q / M maintenance rate on toner carrier (H / H)>
The toner on the solid black image photoreceptor was collected by suction with a metal cylindrical tube and a cylindrical filter, and at that time, the charge amount Q stored in the condenser and the collected toner mass M were measured through the metal cylindrical tube. . From this, the amount of charge Q / M (mC / kg) per unit mass was calculated and used as the initial Q / M (mC / kg) on the photoreceptor. Further, after passing 1,000 sheets of an image with a printing ratio of 1%, the Q / M on the photoconductor after durability was measured in the same manner as the Q / M on the photoconductor in the initial stage. And Q / M maintenance factor (%) was computed from the following formula, and it judged with the following index.
Q / M retention rate (%) = (Q / M on the photoconductor after endurance) / (Q / M on the initial photoconductor) × 100
A: Q / M maintenance rate is 90% or more B: Q / M maintenance rate is 80% or more and less than 90% C: Q / M maintenance rate is 70% or more and less than 80% D: Q / M maintenance rate is 60% or more Less than 70% E: Q / M maintenance rate is less than 60%

<Fog on photoconductor (H / H)>
After passing 1,000 sheets of an image with a printing ratio of 1%, tap the fog toner on the photoreceptor of a solid white image, attach the tape to the blank paper, and the fog density (% by the difference from the tape without taping) ) Was calculated. For fog measurement, TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.) was used, and the average value of 5 points was used as the fog density (%), and the determination was made according to the following index.
A: fog 10% or less B: fog 10% or more but less than 15% C: fog 15% or more but less than 20% D: fog 20% or more but less than 25% E: fog 25% or more

<Fog on paper (H / H)>
After passing 1,000 sheets of an image with a printing ratio of 1%, a solid white image was passed, and the fog density (%) was calculated by the difference from non-passing paper. For fog measurement, TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.) was used, and the average value of 5 points was used as the fog density (%), and the determination was made according to the following index.
A: Fog less than 1.5% B: Fog 1.5% to less than 2.0% C: Fog 2.0% to less than 2.5% D: Fog 2.5% to less than 3.0% E: Fog 3.0% or more

<Morning fog (H / H)>
After passing 1,000 sheets of an image with a printing ratio of 1%, the sheet was allowed to stand for 3 nights, a solid white image was passed again, and the fog density (%) was calculated based on the difference from non-passing paper. For fog measurement, TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.) was used, and the average value of 5 points was used as the fog density (%), and the determination was made according to the following index.
A: Fog less than 1.5% B: Fog 1.5% to less than 2.0% C: Fog 2.0% to less than 2.5% D: Fog 2.5% to less than 3.0% E: Fog 3.0% or more

<Examples 2 to 14 and Comparative Examples 1 to 7>
Evaluation was performed in the same manner as in Example 1 except that the toner was changed as shown in Table 2. The evaluation results are shown in Table 2.
<Example 15, Comparative Example 8>
The evaluation machine was a commercially available color laser printer Color Laser Jet CP4525 (manufactured by HP), the cleaning blade was removed from the black cartridge, and the image was evaluated using toners 15 and 23. And evaluated. The evaluation results are shown in Table 2.

100: electrostatic latent image carrier (photoconductor), 102: toner carrier, 114: transfer member (transfer roller), 117: charging member (charge roller), 121: laser generator (latent image forming means, exposure device) ), 123: Laser, 124: Pickup roller, 125: Conveyor belt, 126: Fixing device, 140: Developing device, 141: Toner stirring member, 142: Toner regulating member, 200: Processed material, 201: High pressure air supply nozzle, 202: Processed product supply port, 203: Airflow injection member, 204: Hot air supply port, 205: Cold air supply port, 206: Second cold air supply port, 207: Cooling jacket, 208: Transfer piping

Claims (5)

A charging step for charging the electrostatic latent image carrier;
An electrostatic latent image forming step of forming an electrostatic latent image on the charged electrostatic latent image carrier;
A developing step of developing the electrostatic latent image with toner on a toner carrier to form a toner image;
A transfer step of transferring the toner image to a transfer material;
A fixing step of fixing the toner image transferred to the transfer material to the transfer material;
An image forming method comprising:
The developing step also serves as a step of collecting the toner remaining on the electrostatic latent image carrier after the transfer step with the toner carrier.
The toner has toner particles containing a binder resin and a colorant and inorganic fine particles,
The inorganic fine particles have Group 2 element titanate fine particles A and silica fine particles B;
The second group titanate fine particles A have a primary particle number average particle diameter (D1) of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 40 mass% or more and 85 mass% or less.
The silica fine particles B have a number average particle diameter (D1) of primary particles of 80 nm or more and 200 nm or less, and a fixing ratio to the toner particles of 50 mass% or more and 95 mass% or less.
The aspect ratio of the toner is 0.880 or more,
When the adhesion between two particles when a load of 78.5 N is applied to the toner is Fp (A), and the adhesion between two particles when a load of 157.0 N is applied to the toner is Fp (B) An image forming method characterized by satisfying the following formulas (1) and (2):
Fp (A) ≦ 30.0 nN (1)
(Fp (B) −Fp (A)) / Fp (A) ≦ 0.60 (2)   2. The image forming method according to claim 1, wherein the group 2 element titanate fine particles A have a primary particle shape of a cube and / or a rectangular parallelepiped and have a perovskite crystal structure.   3. The image forming method according to claim 1, wherein the Group 2 element titanate fine particles A and / or silica fine particles B are treated with an alkylsilane.   The image forming method according to any one of claims 1 to 3, wherein a half-value width of a maximum peak obtained at a particle size of 80 nm to 200 nm in a weight-based particle size distribution curve of the silica fine particles B is 25 nm or less. The image forming method according to claim 1, wherein the toner has an aspect ratio of 0.900 or more.