JP2006259169A - Toner for electrostatic latent image, method for manufacturing toner for electrostatic latent image, and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for non-magnetic one-component development which is excellent in flow property and does not cause problems of adhesion of a toner component to a photoreceptor, and to provide a toner for non-magnetic one-component development which is excellent in environmental stability and does not cause image deterioration due to changes in humidity or a temperature and solves the problem of the voids of the image etc., and further to provide the toner for non-magnetic one-component development suitable for full-color image formation. <P>SOLUTION: The toner for non-magnetic one-component development contains (I) at least three kinds of external additives composed of the external additive A, in which the first component among the external additive is the external additive A composed of hydrophobic silica of ≤10 nm in number average particle diameter of primary particles, the second component is the external additive B composed of hydrophobic inorganic oxide of 10 to 50 nm in number average particle diameter of the primary particles, and the third component is composed of the external additive C which is titanate particulate having the rectangular parallelepiped shape of the titanate particulate and being 20 to 300 nm in the number average particle diameter of the primary particles connecting diagonal lines. The toner for non-magnetic one-component development contains (II) toner base particles. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrostatic latent image toner, a method for producing an electrostatic latent image toner, and an image forming method.

  Conventionally, in electrophotography, the electrostatic latent image formed by charging and exposing the surface of a photoreceptor is developed with a colored toner to form a toner image, and the toner image is transferred to a transfer medium such as transfer paper. This is fixed with a heat roll or the like to form an image. Dry development methods employed in electrophotography, electrostatic recording, and the like include a method using a two-component developer composed of a toner and a carrier and a method using a one-component developer not containing a carrier. The former method provides a relatively stable and good image, but it is difficult to obtain a constant quality image over a long period of time because carrier deterioration and a change in the mixing ratio of toner and carrier are likely to occur. Also, there are difficulties in maintaining and managing the apparatus and downsizing. In view of this, a method using the latter one-component developer which does not have such drawbacks has been attracting attention.

  Further, such a toner may have characteristics such as a small fluctuation range of the toner charge amount with respect to environmental changes such as temperature and humidity, and the fact that the toner component does not adhere to the photoreceptor. Required. However, there are various technical problems to satisfy all the above-mentioned characteristics. For example, in order to improve fluidity, it is effective to externally add silica fine particles to the toner and increase the addition amount, but environmental stability is lowered. When titania particles or alumina particles are added to improve environmental stability, the total amount of external additives added to the toner increases, so the amount of external additives that pass through the cleaning blade and adhere to the surface of the photoreceptor is also increased. This increases the external additive as a core, and other toner components adhere to the bottom so as to draw a skirt at the time of cleaning, and the problem of fixing to the photoreceptor becomes remarkable. If the amount of the external additive is reduced so that the sticking does not occur, not only the fluidity becomes insufficient, but also toner aggregation occurs due to stress in the developing device at the time of printing durability, and the solid image White spots or filming problems occur (Patent Document 1).

  In recent years, oilless fixing devices that have eliminated the fixing oil application mechanism or reduced the application amount have become mainstream from the viewpoint of miniaturization and cost reduction of the fixing device. It has become necessary to contain an agent (wax). However, if the amount of wax on the surface of the toner increases due to the inclusion of wax in the toner, the toner adheres to the regulating blade and the photoreceptor in the developing machine due to the wax due to mechanical / thermal action, or a solid image. There is a problem that white spots / white streaks due to these fixing components or filming of the photosensitive member due to wax is likely to occur.

Japanese Patent Laid-Open No. 2003-255609

  SUMMARY OF THE INVENTION An object of the present invention is to provide a non-magnetic one-component developing toner which has excellent fluidity and does not cause a problem of adhesion of a toner component to a photoreceptor, and an external additive used in the production thereof. Another object of the present invention is to provide a toner for non-magnetic one-component development that has excellent environmental stability, does not cause image deterioration due to changes in humidity and temperature, and solves problems such as image blanking. Another object of the present invention is to provide a non-magnetic one-component developing toner suitable for full-color image formation.

In the first aspect of the present invention, (a) the first component of the external additive is an external additive A made of hydrophobic silica having a number average particle diameter of primary particles of 10 nm or less, and the second component is a primary component. External additive B made of a hydrophobic inorganic oxide having a number average particle size of 10 to 50 nm, the third component is titanate fine particles, and the shape of the titanate fine particles is a rectangular parallelepiped. A non-magnetic single component comprising at least three types of external additives composed of an external additive C having primary particles having a number average particle diameter of 20 nm to 300 nm and (b) toner base particles The present invention relates to a developing toner.
In the second aspect of the present invention, a toner binder component comprising at least a modified polyester resin capable of reacting with active hydrogen, a colorant, and a release agent are dissolved or dispersed in an organic solvent to obtain a toner material liquid, which is used in an aqueous medium. The toner base particles obtained by reacting with a crosslinking agent and / or an extender in the state of being dispersed in the toner, removing the solvent from the obtained dispersion, and washing and removing the resin fine particles adhering to the surface of the toner base particles The toner according to claim 1, wherein the toner is obtained by externally adding the external additive.
The third aspect of the present invention relates to the toner for nonmagnetic single component development according to claim 1 or 2, wherein the particle diameter thereof is 3 to 8 μm.
The fourth aspect of the present invention relates to the nonmagnetic one-component developing toner according to any one of claims 1 to 3, which has an average circularity of 0.950 or more.
The fifth aspect of the present invention is that the content of titanate fine particles in the nonmagnetic one-component developing toner is 0.5 to 4 parts by weight with respect to 100 parts by weight of the toner. The present invention relates to a magnetic one-component developing toner.
A sixth aspect of the present invention is an image forming method for forming a color image with at least black toner and chromatic color toner, wherein the electrostatic latent image is developed with toner of each color possessed by a plurality of developing devices. A developing process by a one-component developing method for forming a toner image on the electrostatic latent image holding member, a transferring step for transferring the toner images of the respective colors formed on the latent image holding member to a recording material, and after the transferring step Blade cleaning process for removing residual toner particles on the latent image holding member by a fixed blade without having a movable part and a pressure adjusting mechanism, and fixing the toner image transferred to the recording material to the recording material 6. An image forming method having a fixing step, wherein the non-magnetic one-component developing toner according to claim 1 is used.
According to a seventh aspect of the present invention, in the image forming method according to the sixth aspect, the fixing means for fixing the toner particle image to the recording material is a heat roll type fixing method, and an oil application method for imparting releasability is used. The present invention relates to an image forming method.

  The toner of the present invention is obtained by externally adding at least three kinds of specific particles composed of a first component to a third component to known toner base particles. In the present specification, “external addition” refers to addition to a toner base particle obtained in advance so as to exist outside the toner base particle.

  In the present invention, the external additive A as the first component uses hydrophobic silica having a primary particle number average particle diameter of 3 to 15 nm, preferably 3 to 10 nm. By externally adding the component, desired fluidity can be imparted to the toner. If the toner does not have the desired fluidity, the charge rising property is deteriorated, and the texture is rough in the initial and final copy images. When the particle size is larger than 15 nm, the fluidity imparting effect is remarkably lowered and sticking occurs. If it is less than 3 nm, the toner coverage increases and the fixability is significantly deteriorated. Moreover, it becomes easy to be buried, and the fluidity is also lowered.

  As the hydrophobic silica used as the external additive A of the first component, conventionally known ones can be used as long as they have the above-mentioned particle size and are hydrophobic. Examples of the hydrophobic silica used as the external additive A of the first component include TS500 (manufactured by Cabogil), R972, R974, R976 (manufactured by Nippon Aerosil Co., Ltd.), H000, H2000 / 4M, and H3004 (manufactured by Clariant). ), Etc. are preferably used. Also, silica or titania having a desired particle size, which has been subjected to a hydrophobic treatment with a known silane coupling agent or silicone oil, may be used.

  The hydrophobicity of the external additive A as the first component is 50% or more, preferably 60 to 70%. If the degree of hydrophobicity is less than 50%, a slight change in environment causes a significant change in toner fluidity and toner charge amount, which is not practical.

  The amount of the external additive A as the first component is 0.05 to 2.00% by weight, more preferably 0.1 to 1.5% by weight, based on the toner base particles. When the addition amount is less than 0.05% by weight, sufficient fluidity cannot be imparted to the toner. On the other hand, if the amount is more than 2.00% by weight, the first component detached from the toner increases, and problems such as fogging and dusting occur at the end of the endurance.

  The external additive B as the second component is a hydrophobic inorganic oxide having a primary particle number average particle size of 10 to 50 nm, preferably 20 to 40 nm, and is larger than the number average particle size of the first component. Inorganic oxides such as hydrophobic silica or hydrophobic titania are used. More preferably, hydrophobic silica having the above particle diameter is used. By externally adding the component, desired fluidity can be easily imparted to the toner. If the particle size is smaller than 10 nm, the second component is embedded in the toner due to the cyclic stress of the developer and the fluidity is remarkably lowered, the effect as a spacer does not come out, the cohesive force of the toner increases, the regulation blade is fixed, This may cause deterioration of transferability. When the particle diameter is larger than 50 nm, the fluidity imparting effect is remarkably reduced.

  As the hydrophobic silica and the hydrophobic titania used as the external additive B of the second component, conventionally known ones can be used as long as they have the above-mentioned particle size and hydrophobicity. For example, as the hydrophobic titania used as the external additive B of the second component, commercially available titanium oxide particles that have been subjected to a hydrophobic treatment can be used. For example, the STT series manufactured by Titanium Industry Co., Ltd., the TTO series manufactured by Ishihara Sangyo Co., Ltd., and the MT series manufactured by Teika Co., Ltd. are commercially available, and these particles are hydrophobized with a known silane coupling agent or silicone oil. It is preferably used. As the hydrophobic silica used as the other external additive B of the second component, for example, RX50, # 70, and # 90 subjected to silane coupling treatment are preferably used. Furthermore, silica having a desired particle size that has been hydrophobized with a known silane coupling agent or silicone oil may be used.

  The degree of hydrophobicity of the external additive B as the second component is 40% or more, preferably 50 to 70%. If the degree of hydrophobicity is less than 40%, a slight change in environment causes a significant change in toner fluidity and toner charge amount, which is not practical.

  The amount of the external additive B as the second component is 0.05 to 2.00% by weight, preferably 0.08 to 1.20% by weight, more preferably 0.1 to 1.0%, based on the toner base particles. % By weight. When the addition amount is less than 0.05% by weight, sufficient fluidity cannot be imparted to the toner. On the other hand, if the amount is more than 2.00% by weight, the second component that is detached from the toner increases, which causes sticking and white spots, and the charging deterioration is remarkable.

The rectangular parallelepiped titanate fine particles used as the external additive C of the third component have a diagonal particle diameter of 20 to 300 nm, preferably 50 to 300 nm. In particular, the average primary particle diameter is a quadratic deviation of the primary particle diameter. A rectangular parallelepiped particle whose value divided by is 0.20 or less is preferable.
As a preferable thing of the rectangular parallelepiped, when two sides of one surface of the rectangular parallelepiped when projected are a and b,
a / b = 20/80 to 80/20
Diagonal particle size [√ (a ² + b ² )] = 20 to 300 nm
It is in a relationship.
By externally adding the component, a static layer composed of the component is formed in the gap between the photosensitive member and the cleaning blade, thereby preventing sludge of other component particles. In addition, when the component efficiently polishes the surface of the photoreceptor, white spots on the image due to fixation due to wax can be further suppressed. In addition, the component functions as a spacer between toners, and transferability is improved.
When the particle size of the external additive C is smaller than 20 nm, the component is not easily accumulated in the gap between the cleaning blade and the photoconductor, and is easily slipped through, so that a static layer is not easily formed. If the particle size is larger than 300 nm, the photoreceptor cannot be uniformly polished, which is not preferable. The third external additive C may be hydrophobized with a known silane coupling agent or silicone oil.

  The rectangular parallelepiped titanate used as the external additive C of the third component may be any known metal titanate such as calcium titanate, barium titanate, strontium titanate, magnesium titanate and the like.

  The amount of the third component external additive C added is 0.4 to 4.0% by weight, preferably 0.5 to 4.0% by weight, more preferably 1.0 to 3.3% by weight based on the toner base particles. 0% by weight. If the amount added is less than 0.4% by weight, formation of a static layer at the blade portion cannot be ensured. When the addition amount is more than 4.0% by weight, the abrasiveness becomes too strong and the life of the photoreceptor is reduced.

When only the external additive A is used as the external additive, the chargeability is excessively increased, the environmental stability is lowered, the polishing effect is not obtained, and the photoreceptor cannot be refreshed.
When the external additives A and B are used in combination as external additives, charging can be suppressed, but the toner coverage increases, the characteristics of the toner base do not appear, the fixability deteriorates, and the polishing effect is reduced. The photoconductor cannot be refreshed.
When external additives A and C are used in combination as external additives, a polishing effect is seen, but they are difficult to adhere to the toner base and are free to cause filming / adhering to the member.
On the other hand, when the three additives A, B, and C are used together as external additives, each of chargeability, environmental stability, polishing effect, toner base property development, and photoreceptor refresh effect are obtained. An extremely well-balanced toner for developing an electrostatic latent image can be produced.

  As a method for producing toner base particles suitably used in the image forming apparatus of the present invention, a known production method can be used. For example, dry pulverization method, wet emulsion polymerization, suspension polymerization, emulsion granulation method As a method for producing toner mother particles that are more preferably used, at least a polyester prepolymer having a functional group containing a nitrogen atom, a polyester, a colorant, and a release agent are dispersed in an organic solvent. This is a method for producing a wet toner obtained by crosslinking and / or extending a toner material liquid in an aqueous solvent. Hereinafter, the constituent material and the manufacturing method of the toner will be described.

(polyester)
The polyester is obtained by a polycondensation reaction between a polyhydric alcohol compound and a polycarboxylic acid compound.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyhydric alcohol (TO) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Phenol novolak, cresol novolak, etc.); Alkylene oxide adducts of the above trivalent polyphenols and the like.

  Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) with a small amount of (TC) Mixtures are preferred. Divalent carboxylic acids (DIC) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  The polycondensation reaction between a polyhydric alcohol (PO) and a polycarboxylic acid (PC) is carried out in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and heated to 150 to 280 ° C. while reducing the pressure as necessary. The produced water is distilled off to obtain a polyester having a hydroxyl group. The hydroxyl value of the polyester is preferably 5 or more, and the acid value of the polyester is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and furthermore, when fixing to a recording paper, the affinity between the recording paper and the toner is good and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly environmental fluctuation.

  The weight average molecular weight is 10,000 to 400,000, preferably 20,000 to 200,000. A weight average molecular weight of less than 10,000 is not preferable because offset resistance deteriorates. On the other hand, if it exceeds 400,000, the low-temperature fixability is deteriorated.

  In addition to the unmodified polyester obtained by the above polycondensation reaction, it is preferable to use a urea-modified polyester in combination with the polyester. A urea-modified polyester is obtained by reacting a polyisocyanate compound (PIC) with a carboxyl group or a hydroxyl group at the terminal of the polyester obtained by the above polycondensation reaction to obtain a polyester prepolymer (A) having an isocyanate group. The molecular chain is cross-linked and / or elongated by reacting amines.

  Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.) Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; phenol derivatives, oximes, polyisocyanates; Those blocked with caprolactam or the like; and combinations of two or more of these.

  The ratio of the polyester and the polyvalent isocyanate compound (PIC) is usually 5/1 as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] of the polyvalent isocyanate compound and the hydroxyl group [OH] of the polyester having a hydroxyl group. ˜1 / 1, preferably 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When the [NCO] / [OH] molar ratio exceeds 5, the low-temperature fixability deteriorates. When the [NCO] / [OH] molar ratio is less than 1, when urea-modified polyester is used, the urea content in the ester is low. Thus, the hot offset resistance may be deteriorated.

  The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance is deteriorated, and it may be disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.

  The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. When the number is less than 1 per molecule, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance may be deteriorated.

  Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acid block of B1 to B5 (B6).

  Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexyl). Methane, diamine cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like.

Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the compound (B6) obtained by blocking the amino group of B1 to B5 include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

The ratio of the polyester prepolymer having an isocyanate group and the amines (B) is equivalent to the isocyanate group [NCO] in the polyester prepolymer (A) having an isocyanate group and the amino group [NHx] in the amines (B). The ratio [NCO] / [NHx] is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2.
When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance may be deteriorated.

  The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance may be deteriorated.

  The urea-modified polyester is produced by a one-shot method or the like. Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having a hydroxyl group. Subsequently, at 40-140 degreeC, this is made to react with polyvalent isocyanate (PIC), and the polyester prepolymer (A) which has an isocyanate group is obtained. Further, this (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester.

  When the polyvalent isocyanate compound (PIC) is reacted and when the polyester prepolymer (A) having an isocyanate group and the amines (B) are reacted, a solvent can be used as necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC), such as tetrahydrofuran (such as tetrahydrofuran).

  In addition, in the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B), the molecular weight of the resulting urea-modified polyester can be adjusted by using a reaction terminator if necessary. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

  The weight average molecular weight of the urea-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance tends to deteriorate. The number average molecular weight of the urea-modified polyester or the like is not particularly limited when the above-mentioned unmodified polyester is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. When the urea-modified polyester is used alone, its number average molecular weight is usually 2000-15000, preferably 2000-10000, more preferably 2000-8000. If it exceeds 15000, the low-temperature fixability and gloss when used in a full-color device tend to deteriorate.

By using the unmodified polyester and the urea-modified polyester in combination, the low-temperature fixability and the glossiness are improved (used in the full-color image forming apparatus), and therefore, it is preferable to use the urea-modified polyester alone. The unmodified polyester may include a polyester modified with a chemical bond other than a urea bond.
The unmodified polyester and the urea-modified polyester are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the unmodified polyester and the urea-modified polyester have a similar composition.

  The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it tends to be disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The glass transition point (Tg) of the binder resin containing unmodified polyester and urea-modified polyester is usually 45 to 65 ° C, preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance of the toner deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient.
In addition, since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the heat-resistant storage stability tends to be good even when the glass transition point is low as compared with known polyester-based toners. The glass transition point (Tg) was accurately measured using a differential scanning calorimeter DSC-200 (manufactured by Seiko Electronics Co., Ltd.), placed in an aluminum pan, and heated from room temperature at a heating rate of 30 ° C./min. After raising the temperature to 200 ° C., it is cooled and measured between 20 ° C. and 120 ° C. at a rate of temperature rise of 10 ° C./min. The shoulder value of the main endothermic peak in the range of 30 ° C. to 90 ° C. during this temperature rise process Was Tg. In addition, the thing which put the alumina in the aluminum pan was used as a reference.

(Coloring agent)
As the colorant, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher , Yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, Parachlor Ortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin Min BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R , Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant can also be used as a master batch combined with a resin. Examples of the resin used in the production of the masterbatch or the binder resin kneaded together with the masterbatch include styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene, and polymers of substitution products thereof, and these and vinyl compounds. Copolymer, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, Examples include terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, and paraffin waxes, which can be used alone or in combination.

(Charge control agent)
A known charge control agent may be used for the toner of the present invention. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus Simple substance or compound, tungsten simple substance or compound, fluorine-based activator, salicylic acid metal salt, metal salt of salicylic acid derivative, and the like. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.

  The amount of charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not uniquely limited. Usually, it is used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the developer fluidity is lowered, and the image density is lowered. May be invited.

(Release agent)
The release agent is not particularly limited, but a low melting point wax having a melting point of 50 to 120 ° C. is more effective as a release agent in the dispersion with the binder resin between the fixing roller and the toner interface. It works against high temperature offset without applying a release agent such as oil to the fixing roller. Examples of such a wax component include the following. Examples of waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as ozokerite and cercin, and paraffin, microcrystalline, And petroleum waxes such as petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, and synthetic waxes such as esters, ketones, and ethers can be used. Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbon, and low molecular weight crystalline polymer resin, poly-n-stearyl methacrylate, poly-n- A crystalline polymer having a long alkyl group in the side chain such as a homopolymer or copolymer of polyacrylate such as lauryl methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used. .
The charge control agent and the release agent can be melt-kneaded together with the master batch and the binder resin, and of course, they may be added when dissolved and dispersed in the organic solvent.

  Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.

(Toner Production Method) [The following (1) to (4) are methods for producing toner base particles, and (5) is a method for externally adding an external additive to the toner base particles]
(1) A toner material solution is prepared by dispersing the colorant, unmodified polyester, polyester prepolymer having an isocyanate group, and a release agent in an organic solvent.
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

(2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant, a resin fine particle dispersant, or an inorganic compound dispersant.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.

  The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical.

Examples of the surfactant include anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, , Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivatives, polyvalent Nonionic surfactants such as alcohol derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine Agents.
Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).
In addition, examples of the cationic surfactant include aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. Benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, trade names include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.), Unidyne DS-202 (Daikin Industries) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products), Footgent F-300 (Neos), and the like.

  The fine resin particle dispersant is added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage ratio (the ratio in which the resin fine particles are coated on the surface of the toner base particles) existing on the surface of the toner base particles is in the range of 10 to 90%. For example, polymethyl methacrylate fine particles (particle size: 1 μm) and 3 μm, polystyrene fine particles: 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles: 1 μm, trade names: PB-200H (manufactured by Kao Corporation), SGP (Sokensha) Product), Technopolymer SB (manufactured by Sekisui Plastics Co., Ltd.), SGP-3G (manufactured by Soken), Micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.), and the like.

  In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

  As a dispersant that can be used in combination with the resin fine particle dispersant or the inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. Examples of the polymer that forms the polymer colloid include acids such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride, Alternatively, a (meth) acrylic monomer containing a hydroxyl group such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid -Γ-hydroxypropyl, methacrylic acid-γ-hydroxypropyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate , Grise Phosphorus monoacrylate, glycerol monomethacrylate, N-methylolacrylamide, N-methylolmethacrylamide, etc., vinyl alcohol or vinyl alcohol ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or vinyl alcohol And esters of compounds containing a carboxyl group, such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, Nitrogen-containing compounds such as vinyl pyridine, vinyl pyrrolidone, vinyl imidazole and ethyleneimine, or homologs such as those having a heterocyclic ring thereof Limer or copolymer; polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene laurylphenyl Polyoxyethylenes such as ether, polyoxyethylene stearyl phenyl ester, and polyoxyethylene nonylphenyl ester, and celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  A method for dispersing the toner base particles is not particularly limited, and known equipment such as a low-speed shearing type, a high-speed shearing type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. Among these, a high-speed shearing method is preferable in order to make the particle size of the dispersion 3 to 8 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

(3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group.
This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

(4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.

(5) The toner base particles obtained in the above (1) to (4) are optionally charged with a charge control agent, and then external additive (a) is externally added to obtain a toner.
The injection of the charge control agent and the external addition of the external additive are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the step of removing the organic solvent, the shape between the spherical shape and the spindle shape can be controlled, and further, the surface can be controlled from smooth to wrinkled. .

  When the external additive (A) comprising the external additive A, external additive B, and external additive C is externally added to the toner base particles, a known external additive can be used as long as these toner constituents can be mixed uniformly. It is possible to use a method. For example, the above three components defined in the present invention may be added to the toner base particles at once and mixed using a Henschel mixer or the like. Further, the three components may be added separately for each component, but it is preferable to add and mix silica, particularly hydrophobic silica used as the first component first. This is because the rising property of charging is further improved.

  According to the present invention, the titanate fine particles as the external additive C can suppress sticking and photoconductor wear, and can provide an excellent effect of improving charging stability. Further, in the present invention, an excellent effect of improving the environmental stability and durability of the toner can be obtained by further controlling the particle diameters and addition amounts of the first component and the second component.

Examples / Comparative Examples Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The following “parts” are by weight unless otherwise specified.

<Production Example of Toner Base Particle>
(Synthesis of low molecular weight polyester)
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 220 parts of bisphenol A ethylene oxide 2-mole adduct, 561 parts of bisphenol A propylene oxide 3-mole adduct, 218 parts of terephthalic acid, 48 parts of adipic acid and dibutyl Add 2 parts of tin oxide, react for 8 hours at 230 ° C. under normal pressure, and further react for 5 hours under reduced pressure of 10-15 mmHg, then add 45 parts of trimellitic anhydride to the reaction vessel, and leave for 2 hours at 180 ° C. under normal pressure. The reaction yielded “low molecular weight polyester 1”. “Low molecular polyester 1” had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25.

[Prepolymer synthesis]
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction tube, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. under normal pressure for 8 hours, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain “Intermediate Polyester 1”. “Intermediate polyester 1” had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, a Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 49.
Next, 411 parts of “Intermediate Polyester 1”, 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1 "was obtained. “Prepolymer 1” had a free isocyanate weight percentage of 1.53%.

[Synthesis of master batch]
Carbon black (Cabot Co., Ltd. Regal 400R): 40 parts, Binder resin: Polyester resin (Sanyo Kasei RS-801 Acid value 10, Mw 20000, Tg 64 ° C.): 60 parts, Water: 30 parts are mixed in a Henschel mixer, A mixture in which water was soaked into the pigment aggregate was obtained. This was kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. and pulverized to a size of 1 mmφ with a pulverizer to obtain “masterbatch 1”.

[Preparation of pigment / WAX dispersion (oil phase)]
In a container equipped with a stir bar and a thermometer, 378 parts of the “low molecular weight polyester 1”, 200 parts of carnauba wax, and 947 parts of ethyl acetate are charged, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. And then cooled to 30 ° C. in 1 hour. Next, 500 parts of “Masterbatch 1” and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain “raw material solution 1”.
Transfer 1324 parts of the “raw material solution 1” to a container, and use a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.) to feed a liquid at a rate of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 80 volumes of 0.5 mm zirconia beads. %, And dispersion was performed under conditions of 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of “low molecular weight polyester 1” was added, followed by one pass with a bead mill under the above conditions to obtain “pigment / wax dispersion 1”. The “pigment / wax dispersion 1” was prepared with ethyl acetate so that the solid content concentration (130 ° C., 30 minutes) was 50%.

(Preparation of aqueous phase)
953 parts of water, 88 parts of a 25 wt% aqueous dispersion of a vinyl resin (styrene salt copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate), 48.48% of sodium dodecyl diphenyl ether disulfonate. 90 parts of 5% aqueous solution (Eleminol MON-7: Sanyo Chemical Industries) and 113 parts of ethyl acetate were mixed and stirred to obtain a milky white liquid. This is designated as “aqueous phase 1”.

[Emulsification process]
976 parts of “Pigment / Wax X Dispersion 1” and 6.0 parts of isophoronediamine as amines were put in a container and mixed at 5,000 rpm for 1 minute with a TK homomixer (manufactured by Tokushu Kika). After adding 137 parts of Prepolymer 1 "and mixing with TK homomixer (manufactured by Special Machine) at 5,000 rpm for 1 minute, add 1200 parts of" Aqueous Phase 1 "and rotating at 13,000 rpm with TK homomixer. Was mixed for 20 minutes to obtain “Emulsion slurry 1”.

[Desolvent]
“Emulsion slurry 1” was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 4 hours to obtain “dispersed slurry 1”.

[Washing → Drying]
After filtering 100 parts of the “dispersed slurry 1” under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 900 parts of ion-exchanged water was added to the filter cake of (1), ultrasonic vibration was applied, and the mixture was mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure. This operation was repeated so that the electric conductivity of the reslurry liquid was 10 μC / cm or less.
(3): 10% hydrochloric acid was added so that the reslurry solution of (2) had a pH of 4, and the mixture was directly filtered with a three-one motor for 30 minutes.
(4): 100 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm) and then filtered. This operation was repeated so that the reslurry liquid had an electric conductivity of 10 μC / cm or less to obtain “filter cake 1”.
The “filter cake 1” was dried with a circulating dryer at 45 ° C. for 48 hours, and sieved with an opening of 75 μm mesh to obtain “toner base 1”. The particle diameter (volume average particle diameter) was 5.6 μm, the number average particle diameter (Dp) was 5.0 μm, and the average circularity was 0.97.

Particle size The particle size distribution was measured using Coulter Multisizer II (manufactured by Coulter).
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution. Here, the electrolytic solution is prepared by preparing an about 1% NaCl aqueous solution using primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume, weight, and number of toner particles or toner are measured using the 100 μm aperture as the aperture by the measuring device. The particle size (volume average particle size) and the number average particle size were calculated.

As a method for measuring the average circularity shape, an optical detection band method is suitable, in which a suspension containing particles is passed through an imaging zone detection zone on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. is there. A toner having an average circularity of 0.950 or more, which is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle, is a high-definition image with a reproducibility of an appropriate density. It turned out to be effective in forming. This value is a value measured as an average circularity by a flow type particle image analyzer FPIA-2000 (manufactured by Sysmex Corporation). As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. About 0.1 to 0.5 g. The suspension in which the sample is dispersed is obtained by performing dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser and measuring the shape and distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. .

<Examples of production of rectangular parallelepiped titanates A and D>
The metatitanic acid obtained by the sulfuric acid method was deiron-bleached and bleached by adding aqueous sodium hydroxide to pH 9.0, neutralized to pH 5.5 with hydrochloric acid, and washed with filtered water. Water was added to the washed cake to prepare a slurry of 1.25 mol / L as TiO ₂ , and hydrochloric acid was added to adjust the pH to 1.2 for peptization treatment. After 0.15 mol of this peptized titanium oxide was collected as TiO ₂ and charged into a 3 L reaction vessel, an aqueous strontium chloride solution having a SrO / TiO ₂ molar ratio of 1.15 was added to the peptized titanium oxide slurry. The TiO ₂ concentration was adjusted to 0.15 mol / L, nitrogen gas was blown in, and the reaction vessel was purged with nitrogen gas for 20 minutes. Next, while flowing nitrogen into the reaction vessel and further stirring and mixing, the mixed solution of metatitanic acid and strontium chloride was heated to 90 ° C., and then 143 mL of a 2.5N aqueous sodium hydroxide solution was added over 24 hours. Thereafter, stirring was continued at 90 ° C. for 1 hour to complete the reaction. After the reaction, it is cooled to 40 ° C., the supernatant is removed under a nitrogen atmosphere, reslurried with a total of 5 L of pure water, filtered through Nutsche, and the resulting cake is dried in the atmosphere at 110 ° C. for 8 hours. did. When the product was observed with an electron microscope, rectangular parallelepiped titanates A and D, which were 0.16 to 0.40 μm particles, which were rectangular parallelepiped particles, were obtained.

<Examples of production of rectangular parallelepiped titanates B and C>
0.6 mol of dehydrated and peptized hydrous titanium oxide as TiO ₂ was sampled and charged into a 3 L reaction vessel, and strontium chloride having a SrO / TiO ₂ molar ratio of 1.15 was added to the peptized titanium oxide slurry. After adding the aqueous solution, the TiO ₂ concentration was adjusted to 0.6 mol / L, nitrogen gas was blown in, and the reaction vessel was purged with nitrogen gas for 20 minutes. Next, while flowing nitrogen into the reaction vessel and further stirring and mixing, the mixed solution of metatitanic acid and strontium chloride was heated to 90 ° C., and then 143 mL of a 10N aqueous sodium hydroxide solution was added over 2 hours. Stirring was continued at 90 ° C. for 1 hour to complete the reaction. After the reaction, it is cooled to 40 ° C., the supernatant is removed under a nitrogen atmosphere, reslurried with a total of 5 L of pure water, filtered through Nutsche, and the resulting cake is dried in the atmosphere at 110 ° C. for 8 hours. did. When the product was observed with an electron microscope, rectangular parallelepiped particles 0.01 to 0.05 μm of rectangular parallelepiped titanates B and C were obtained.
In rectangular strontium titanates A, B, C, and D, as a result of observation with TEM, the values of a and b in Table 1 were calculated, and the average primary particle diameter was calculated.

<Example of production of tufted strontium titanate A>
Added to metatitanic acid slurry obtained by a sulfuric acid method, after adding _{SrC l2} of TiO ₂ with an equimolar amount, the CO ₂ gas at a flow rate of 1L / min to 2 times the molar amount blown simultaneously aqueous ammonia TiO ₂ did. At this time, the ph value was 8. The precipitate was washed with water, dried at 110 ° C. for 1 day, and sintered at 900 ° C. to obtain strontium titanate particles A having a number average particle size of 300 nm. The shape of the obtained strontium titanate A was observed with an electron microscope. As a result, kitchen-like aggregates had an average diameter of 250 nm.

<Hydrophobic silica>
For the hydrophobic silicas A, B, C, D, E, and F used in this example, silica having particle sizes shown in Table 2 was used.

<Example of Toner External Addition / Comparative Example>
The first component, the second component, and the third component shown in Table 2 are added to 1 kg of “toner base 1” in the amount (parts by weight of the external additive relative to 100 parts by weight of “toner base 1”), Mixing was performed with a Henschel mixer at a peripheral speed of 20 m / s for 10 minutes.

<Evaluation> The developers obtained in each Example and Comparative Example were evaluated according to the following methods for each evaluation item, and the results are shown in Table 3.

Charging Stability Using a full color printer LP-1500C (manufactured by Epson Corporation), a predetermined print pattern with a printing rate of 6% was continuously printed in an N / N (23 ° C., 45%) environment. After continuous printing of 50 and 2000 sheets in N / N environment (after endurance), the toner on the developing roller during blank pattern printing is sucked and the amount of charge is measured with an electrometer. After 50 and 2000 sheets The difference in charge amount was evaluated.
○: Absolute value of charge amount difference is 10 μC / g or less Δ: Absolute value of charge amount difference is more than 10 μC / g and within 15 μC / g ×: When the absolute value of charge amount difference is more than 15 μC / g

Using a fixed full color printer LP-1500C (manufactured by Epson Corporation), a predetermined print pattern with a printing rate of 6% was continuously printed in an N / N (23 ° C., 45%) environment. After continuous printing (after endurance) in an N / N environment, the photosensitive member and the intermediate transfer belt were visually observed and evaluated. Judgment criteria are as follows.
○: There was no problem on the photoconductor and the intermediate transfer member, and there was no problem. Δ: Adherence was observed on either the photoconductor or the intermediate transfer member.
It was not visible on the image and there was no problem in practical use. X: There was sticking on the photosensitive member and / or the intermediate transfer member.
There was a practical problem

Using a full color printer LP-1500C (manufactured by Epson Corporation), a predetermined print pattern with a printing rate of 6% was continuously printed in an N / N (23 ° C., 45%) environment. After continuous printing (after endurance) in an N / N environment, the photosensitive member and the intermediate transfer belt were visually observed and evaluated. Judgment criteria are as follows.
○: Filming does not occur on the photosensitive member and the intermediate transfer member, and there is no problem.
Δ: Filming was observed on either the photoconductor or the intermediate transfer member.
However, it was not visible on the copied image and there was no problem in practical use. ×: Filming occurred on the photoreceptor and / or the intermediate transfer member.
There was a problem in practical use.

  In the present specification, the particle diameters of the first component to the third component are values calculated from a TEM observation photograph.

Claims (7)

  (A) The first component of the external additive is an external additive A made of hydrophobic silica having a primary particle number average particle size of 10 nm or less, and the second component has a primary particle number average particle size. The external additive B made of a hydrophobic inorganic oxide of 10 to 50 nm, the third component is titanate fine particles, the shape of the titanate fine particles is a rectangular parallelepiped, and the primary particles having diagonal lines A toner for non-magnetic one-component development comprising at least three types of external additives composed of an external additive C having a number average particle diameter of 20 nm to 300 nm and (b) toner base particles.   At least a toner binder component consisting of a modified polyester resin capable of reacting with active hydrogen, a colorant, and a release agent are dissolved or dispersed in an organic solvent to form a toner material liquid, which is crosslinked in an aqueous medium. After the reaction with the agent and / or the extender, the solvent is removed from the obtained dispersion, and the resin fine particles adhering to the surface of the toner base particles are washed and detached. The nonmagnetic one-component developing toner according to claim 1, wherein the toner is obtained by adding.   The nonmagnetic one-component developing toner according to claim 1 or 2, wherein the particle diameter is 3 to 8 µm.   The nonmagnetic one-component developing toner according to claim 1, which has an average circularity of 0.950 or more.   The toner for nonmagnetic one-component development according to any one of claims 1 to 4, wherein the content of titanate fine particles in the toner for nonmagnetic one-component development is 0.5 to 4 parts by weight with respect to 100 parts by weight of the toner.   An image forming method for forming a color image with at least black toner and chromatic color toner, wherein the electrostatic latent image is developed with toner of each color possessed by a plurality of developing devices, and the electrostatic latent image is retained. A developing process using a one-component developing method for forming a toner image on the body, a transferring process for transferring the toner images of the respective colors formed on the latent image holding body to a recording material, and a latent image holding body after the transferring process. An image forming method comprising: a blade cleaning step of removing residual toner particles by a blade fixed without having a movable part and a pressure adjusting mechanism; and a fixing step of fixing a toner image transferred to the recording material to the recording material An image forming method using the nonmagnetic one-component developing toner according to claim 1. 7. The image forming method according to claim 6, wherein the fixing means for the toner particle image to the recording material is a heat roll type fixing method, and an oil application method for imparting releasability is not used. Forming method.