JPS5953856A - Production of toner - Google Patents

Abstract

PURPOSE:To provide a producing method by suspension polymn. of a toner having narrowed distribution of particles and good fluidity, by dispersing pulverized powder of hydrophilic silica having negative electrostatic chargeability in a dispersion medium to prevent the coalscence of suspended particles. CONSTITUTION:A monomer system dissolved or dispersed uniformly with a toner material consisting of pulverized powder of silica treated with a surface treating agent having positive electrostatic chargeability and a surface treating agent for providing hydrophobic nature a synthetic resin monomer such as an alpha-beta unsatd. monomer, a vinyl monomer or the like, a polymn. initiator, magnetic material, etc. is dispersed into the aq. phase contg. the pulverized powder of hydrophilic silica having negative electrostatic chargeability which is a suspension stabilizer, by using a homomixer or the like. The speed and time for agitation are so adjusted that the liquid drops of the monomer have the sizes less than the sizes of the toner particles, that is, <=30mum sizes. The polymn. temp. is set at 70- 90 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing toner for developing electrostatic images and the like.

Conventionally, toners have generally been produced by melt-mixing colorants and other additives in a thermoplastic resin, uniformly dispersing the mixture, and then using a pulverizer and a classifier to produce toners having a desired particle size. Although this manufacturing method can produce fairly good toners, it does have certain limitations. That is, there are certain limitations on the selection range of toner materials. For example, the 4i/J fat pigment dispersion must be sufficiently brittle that it can be comminuted at manufacturing speeds that are commercially possible. This requirement causes the problem that the resin pigment dispersion is sufficiently brittle that when it is actually pulverized at high speed, a wide particle size range is likely to be formed by the pulverization, and a relatively large proportion of the fine particles are agitated in this. Furthermore, the fee that is fragile in taste like this is 8 for the copy machine? When using it for development, it is sometimes further finely pulverized or
undergoes pulverization. Other requirements for toners include being stable in the liver, non-clotting, and IIζ1. These requirements include: having all the characteristics of a friction zone, forming an excellent image, not contaminating the surface of the light and light body, and having appropriate heat fixing properties. , combined with additional requirements imposed on this toner formation method.

1 ton of electrostatic image developing toner obtained by suspension polymerization
-, ↓, This method overcomes the drawbacks of the pulverization method.

In other words, brittleness is not necessary since there is no pulverization process involved, and the spherical shape provides excellent fluidity, resulting in uniform triboelectrification. Furthermore, by appropriately controlling polymerization and using a crosslinking agent, a toner with excellent heat fixing properties can be obtained.

However, it is technically difficult to perform polymerization in a stable suspended system without coalescence and to obtain fine polymer particles with a uniform particle size distribution through polymerization. Therefore, when suspension polymerizing the polymerizable W'-acid system in water,
Suspension stabilizers are used to prevent coalescence of the polymer particles as the polymerization progresses. Stabilizers that are generally used as stabilizers are broadly classified into water-soluble polymers and poorly soluble fine powder inorganic compounds; the former include gelatin, starch, polyvinyl alcohol, etc., and the latter include Ba804. CaSO4,
BaC0,, MgC0,, C8% (PO4), , C
aeO.

There are powders of dissolvable salts, talc, clay, silicic acid, diatoms, inorganic polymers, and metal oxides.

In addition to the selection of the stabilizer, stirring is an important condition for suspension polymerization, and this determines the particle size and stability of polymerization. Low-speed stirring causes gelation and makes it impossible to obtain polymer particles. On the other hand, with high-speed stirring, polymer particles with small particle diameters are formed; however, due to the introduction of air into the pushing device 4, oxygen has the effect of inhibiting radicals, resulting in a decrease in the polymerization yield and a decrease in the degree of merging. .

Related to this, there is the problem of liquefaction (ilr, ratio of synthetic monomer: water), which is usually in the range of 5 to 1:8, and when the amount of monomer is low and the amount of monomer is low, it becomes a gel. It is easy to become confused and fail. 51 In general, the particle size distribution is wide.

On the other hand, depending on the conventional suspension polymerization method, 30μ
m7! It was very difficult to obtain polymer particles of 100% or less. In other words, as the viscosity of the polymer particles gradually increases as polymerization progresses, the particles increase their adhesive strength, and even pressing cannot prevent the particles from coalescing, causing the particle size to increase and gelation to occur. cause In order to prevent this TJJ phenomenon, adjuvants are used in addition to stabilizers. A method of adding glycol, glycerin, etc. to increase the viscosity/li of the medium and prevent particle coalescence, and a method of adding Na to increase the interfacial tension between water and particles.
A method of adding an electrolyte such as C1, Na, 804, etc. has been adopted.

However, even with these methods, it is difficult to obtain fine particles with a particle size that is satisfactory for a toner, that is, a number average diameter of about 10μ to 20μ. This is because, in the end, there are not enough ways to prevent union. In addition, in the combination of a polymerizable monomer and an inorganic dispersant, the interface of the polymerizable monomer particles becomes cationic by adding a cationic polymerizable monomer or a miscellaneous water-soluble organic amine compound.
Alternatively, it is anionically charged by adding an anionic polymerizable monomer.

On the other hand, the inorganic dispersant has a charge opposite to that of the polymerizable monomer particles, and therefore completely and uniformly covers the surface of the polymerizable monomer particles with strong ionic bonds to prevent coalescence. A method of obtaining fine particles having a number average diameter of about io to 20 μm has been proposed.

This method uses colloidal silica (StO, ) and bentonite (Sin, /N) as anionic dispersants.
-tos), and aluminum oxide (A/!tOs) is used as the cationic material. As a result, these particles completely cover the surface of the toner fine particles that are finally subjected to 44F. However, in order for the toner to be satisfactory, it is necessary to apply an appropriate amount of negative or V-positive charging due to frictional charging or the like.

Colloidal silica itself is strongly negatively charged, so
You can obtain toner of regret and desire.

However, aluminum oxide (A-gtOs) becomes quite strongly positively charged in water, but when it is dried and obtained as a toner, the positive charge is as small as an elbow, which is a practical problem.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for producing a toner produced by suspension polymerization, which solves these drawbacks.

That is, the present invention provides a new toner for developing an electrostatic image, which has a disadvantage and disadvantages.

Further, the present invention provides a method for producing a toner having a narrow particle size distribution and an appropriate particle size.

Furthermore, the present invention provides a toner for developing electrostatic images that has good fluidity and excellent image quality. .

The feature is that a toner material containing a hydrophobic positively chargeable silica fine powder, a synthetic resin monomer, and a polymerization initiator is mixed with a toner material containing a hydrophilic negatively chargeable silica fine powder and a synthetic resin monomer and a polymerization initiator. The method of producing a toner includes a step of dispersing the toner in a dispersion medium that is hardly compatible with the toner and carrying out suspension polymerization.

That is, when a hydrophobic iE-chargeable silica fine powder is dispersed in an L1 monomer system, it is easily dispersed, and even when such a monomer system is suspended in a dispersion medium, it does not come out into the dispersion medium at all. Therefore, if the hydrophilic negatively charged silica fine powder is completely dispersed in such a dispersion medium, the hydrophobic surface charged silica fine powder at the suspended particle interface and the hydrophilic negatively charged silica fine powder in the dispersion medium will be electrostatically charged. They are bonded by physical attraction, and fine particles with a narrow particle size distribution and suspended particles can be easily obtained.

The toner thus obtained has good fluidity, uniform charging, and good image quality.

The hydrophobic positively chargeable silica fine powder contained in the monomer system is preferably 50 kf()A: F or less, and more preferably 10 to 0.1 weight h1 part, based on 100 parts by weight of the single sleeve body. Further, the hydrophilic negatively charged silica fine powder contained in the dispersion medium is preferably 10 parts or less of heavy acid per 100 parts of leather, and 5
~0.1 part by weight is more preferred.

For the fine silica powder used in the present invention, any commonly used positively charging surface treating agent and hydrophobizing surface treating agent may be used. As a positively charged surface treatment agent, for example, the general formula Xr
There is one represented by n8iYn. Here, X) is an alkoxy group or a chlorine atom. m: l or V, 2 or 3
゜Yl is a hydrocarbon group having a primary to tertiary amino group. n;
3 or 2 or 10 Specifically, there are the following.
ICI, H,N-Cl2CH2NHCH,CH□C1(2Si
-(OCH8).

1(,N-C0NH-CH,CH,CH12-8i -
(OC2■u).

to N-CH, CH, CH, 5r(OCH, CH,).

11, NCl-I20H2NHCH, CIJ, C1l,
Si (OCHs).

H2NC)12Ctl,CH,8i(OCH,).

H2N Cll2e 11. Nt(CII, CII, N
HCI(,CI,CH2Si(OCH,).

H, C, 0 COCH, C) I, N1-IC gu CI l,
CLl,8 i (OCH,,),H,C,0COel
l, CH, NHCH, CH(, NHCII, CII, C
I, Si (OCH,), CJ-18NHC112C1
12C)12Si(OCR,)s or polyaminoalkyltrialkoxysilane, etc., which are 1(
They may be used in combination or in a mixed system of two or more.

Examples of hydrophobic surface treatment agents include silane coupling agents and titanium coupling agents. Specifically, it is as follows.

r-chloropropyltrimethoxysilane ClIC, [1
, S i (OCtl,).

vinyl trichlorosilane CHr:CH31Cz.

Vinyltriethoxysilane CH, -CH8j (QC, II,), l vinyltris(βmethoxyethoxy)silane CH.

CI, =C■(cOOc, H65i(OCR,).

β-(3,4Evoxinchlorohexyl)ethyltrimethoxysilane r-glycidoxyglobiltrimethoxysilane r-mercaptopropyltrimethoxysilane Use, H
,5i(OCH,)3 r-aminopropyltriethoxysilane H,NC C9[
(,S i (OC,H,)aN-β-(aminoethyl)-r-aminopropyltrimethoxysilane H,NC,tJ4NHCJI,S i (OCII,)
3γ-ureidoglopyltriethoxysilane H2NC0
NHC31(,8i(QC,H,)3N-β-(aminoethyl)-r-aminopropylmethyldimethoxysilane CH3 N2N C2H4N He, H6S i (OCH3)
s isopropyl triisostearoyl titanate isopropyl tridodecylbenzenesulfonyl titanate bis(di-tridecyl) phosphite titanate titanate bis(dioctyl pyrophosphate) ethylene titanate A general method may be used to treat the silica fine powder. For example, the treatment can be carried out by stirring fine silica powder and adding a solution of the treatment agent little by little to it. Also,
There is a method of vaporizing (7) spraying a processing agent or its solution onto fine silica powder in a gas phase.

As for the treatment agent, the positively charging surface treatment agent may be treated and then the hydrophobizing surface treatment agent may be treated anew, or both surface treatment agents may be mixed in an appropriate ratio and treated at the same time. Additionally, several grammes of a treatment agent may be used.

The hydrophilic negatively charged silica fine powder used in the present invention includes:
Common ones are used, but for example, Aerosil≠1
30. +200. =I=300.180 (Nippon Aerosil Co., Ltd.) can be used.

In the present invention, an anionic associative monomer may be used at the same time.

Examples of the anionic associative monomer used in the present invention include the following. 2-acrylamido-2-methylpropanesulfonic acid, N-methylolacrylamide,
Methacrylic acid, acrylic acid, 2-hydroxyethyl methacrylate, 2-hydroquinpropyl methacrylate,
These include glycidyl methacrylate, polyethylene glycol monomethacrylate, polyethylene glycol monomethacrylate, tetrahydrofurfuryl methacrylate, and acid phos-oxyethyl methacrylate.

However, it is necessary that these substances Q coexist in the polymerizable 'l-ft' particles, and therefore water-soluble organic amines cannot be used.

However, even if the ionic associative monomer is water-soluble, it becomes part of the electropolymer particles by copolymerizing during the polymerization process, and does not remain in the aqueous phase.

Suitable dispersion media used in the present invention include, for example, any suitable stabilizer, such as polyvinyl alcohol,
Gelatin, methyl cellulose, methyl hydroglobil cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and their salts, starch, gum alginate, zein, casein,
Tricalcium phosphate, talc, barium sulfate, aluminum, bentonite, aluminum hydroxide, ferric hydroxide, titanium hydroxide, thorium hydroxide, and the like can be incorporated into the aqueous phase. The stabilizer is in a stabilizing amount in the continuous phase, preferably in the range of about 0.1 to 10% by weight.

In addition, for fine dispersion of the inorganic dispersant, 0.001-
Surfactants in the range of 0.1% by weight may also be used. This is to promote the intended action of the above-mentioned dispersion stabilizer, and specific examples thereof include sodium dodecylbenzenesulfonate, sodium tetradecylsulfate, sodium pentadecylsulfate, sodium octylsulfate, and allyl-alkyl-polymerizate. Sodium ether sulfonate, sodium oleate, sodium laurate,
Sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, 3.3'-disulfonodiphenylurea 4.4
'-Sodium cyacibis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2.5.5-tetramethyl-
Triphenylmethane-4,4'-diazo-bis-β-
Examples include sodium naphthol-disulfo/acid, and others.

However, monomers that are easily soluble in water cause emulsion polymerization in water at the same time, and the resulting MM turbid polymer is contaminated with small emulsion polymer particles. It is also good to prevent this. Furthermore, in order to increase the viscosity of the medium and prevent coalescence of particles, glycerin, glycol, etc. may be added to the water. In addition, due to the decrease in water solubility of easily soluble monomers [NaCe, KC/, Na, 8
It is also possible to use salt/Isamu such as 04.

As the polymerization initiator, any suitable polymerization initiator may be used, such as azobisisobutyronitrile (AI8N), penzoyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxy carbonate, cumene hydroperoxide, 2,4- Monomer polymerization can be carried out using dichloryl benzoyl peroxide, lauroyl peroxide, or the like.

Generally, about 0.5 to 5% of initiator by weight of the succulent is sufficient.

The polymerization temperature is usually 50°C to 120°C, but uniform polymerization is more likely to occur at lower temperatures.

In the present invention, as monomers, specific examples of polymerizable monomers for producing polymer particles of toner include α-β unsaturated monomers, such as styrene, 0-methylstyrene, and -methylstyrene, p-methylstyrene, p
-ethylstyrene, 2,4-dimethylstyrene, p”
7" silstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-1 nonylstyrene, P" 7silstyrene, p-n-dodecylstyrene, p-methoxystyrene , p-phenylstyrene, p-chlorostyrene, 3
．． Examples include styrene and its derivatives such as 4-dichlorostyrene, and among these, styrene monomer is the most preferred. Other vinyl monomers include, for example, ethylene unsaturated monomerfins such as ethylene, propylene, butylene, and isobutylene; vinyl chloride, vinylidene chloride,
Vinyl halides such as vinyl bromide and vinyl fluoride; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl butyrate; methyl acrylate;
Ethyl acrylate, n-pudyl acrylate, isobutyl acrylate, globil acrylate, T1-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α - Methyl chloroacrylate, methyl methacrylate, edyl methacrylate, propyl methacrylate, f4In-butyl methacrylate, isobutyl methacrylate, +1-octyl methacrylate,
α-methylene aliphatic monocarboxylic acids and esters such as dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, and jetylaminoethyl methacrylate; acrylonitrile, methacrylaterile, Acrylic acid or methacrylic acid derivatives such as acrylamide; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl methyl ketone, vinyl hexyl ketone,
Vinyl ketones such as methyl isopropenyl ketone; N
- N-vinyl compounds such as vinylpyrrole, N-vinylcarbazole, N-vinylindole, and N-vinylpyrrolidone; vinylnaphthalenes; and the like.

The polymer according to the present invention may be polymerized in the presence of a crosslinking agent to form a crosslinked aggregate. Preferably used crosslinking agents are mainly compounds having two or more polymerizable double bonds, such as aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and derivatives thereof, such as ethylene glycol dimethacrylate, Diethylene glycol methacrylate, triethylene glycol methacrylate, trimethylolpropane triacrylate, allyl methacrylate, t-butylaminoethyl methacrylate, tetraethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, etc., diethylene carboxylic acid esters, N, N
- All divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and compounds having three or more vinyl groups are selected singly or as a mixture. Furthermore, ethylene glycol, triethylene glycol, 1.2-7' lopyre/glycol, 1.3-7' robylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butynediol, Dihydric alcohols such as 4-bis(hydroxymethyl)cyclohexane, bisphenol A1, hydrogenated bisphenol A1, borimexyethylated bisphenol A1, polyoxypropylenated bisphenol A; maleic acid, fumaric acid, mezaconic acid, citraconic acid , itaconic acid, glutaconic acid, phthalic acid 8, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, cono-phosphoric acid, adipic acid, cepatic acid, malonic acid, their anhydrides and their esters with lower alcohols, etc. Dibasic acids and their derivatives; 3 such as glycerin, trimethylolpropane, pentaerythritol, etc.
Alcohols having a valence of 30 or more and carboxylic acids having a valence of 30 or more, such as trimellitic acid and pyromellitic acid, are used as crosslinking agents in the present invention.

The addition of such a crosslinking agent to the monomers is selected in the range of 5 to 20% by weight, preferably 0.1 to 5% by weight9. If the amount added is too large, the toner will not melt and will tend to lose its fixing properties as a toner.

Also, if the amount is too low, the durability and storage stability of the toner will deteriorate.
It becomes difficult to impart properties such as abrasion resistance, and the molecular weight distribution of the polymer expands and its bonds become narrower due to crosslinking, especially in hot roll fixing type copying machines and the like.

Common colorants (known as IC) are used as colorants for toners.
It is possible to use dyed face n. Furthermore, carbon black and magnetic materials can also be used. In particular, a magnetic material such as C6-J magnetite 75 or a surface-treated material is also good.

The suspension method involves uniformly dissolving or dispersing the polymerization initiator, magnetic material, monomer, and additives (a) and the i11 system in an aqueous phase containing all of the suspension stabilizers, i.e., continuous The mixture is dispersed in the phase using a conventional stirrer, homomixer, 71z modifier, etc. Preferably, the agitation speed and time are adjusted so that the monomer droplets have the desired toner particle size, generally less than 30 microns, and are then maintained that way by the addition of a fractional stabilizer. The stirring may be carried out to the extent that sedimentation of the particles is prevented. The market temperature is 50℃ or higher,
Polymerization is generally carried out at a temperature of 70°C to 90°C. After the reaction is completed, the generated toner particles are collected by an appropriate method such as washing, filtration, decantation, centrifugation, etc.
dry.

The examples were uniformly mixed for about 10 minutes in a vessel equipped with a high shear mixing device such as a TK Homomixer (manufactured by Tokushu Kogyo Mon). Hydrophobic iE-banded silica fine powder It was obtained by treating the silica fine powder with H, N C Tsuru CH, CH, 8i (UCl(,,)s).Meanwhile, the temperature was about 55°C.
The vortex rose to . During this time the pigment was uniformly dispersed in the styrene monomer.

2 tons of Aerosil≠300 (manufactured by Nippon Aerosil Co., Ltd.) fine powder was dispersed in 6001 water using the above TK homomixer, and 7
The above slurry was put into a system kept at 0° C. under stirring by a TK homomixer, and stirred at 4000 rpm+n for 30 minutes. Thereafter, this reaction mixture system was stirred with a paddle blade for 11 minutes to complete the polymerization. Washed with water, filtered and dried, number average diameter 1
0.2μ, number distribution is 635μ or more, 215g, volume distribution is 20.2μ or more, 39g (Coulter counter, l
(Using OOμ aperture) was obtained.

This toner'f:200/300 iron powder carrier and 1(
)% mixture, and the result of measuring tribo using the Prouo 7 method,
-5,6ttc/V was obtained. Furthermore, this toner is used as a two-component developer, and N1. ' -5 (100) and a good image could be obtained.

[Example 2] was subjected to suspension polymerization in the same manner as in Example 1.

The hydrophobic, aqueous positively chargeable silica fine powder is a silica fine powder H,N-C0NII-Cf12C[I, C1l, -8i
-(OCJ(,).

It was obtained by processing with fu. Furthermore, Aerosil-420'0 (manufactured by Nippon Aerosil Co., Ltd.) was used as the hydrophilic powder W and fine silica powder. After washing with water, filtering and drying, the number average diameter was 9.5μ, the number distribution was 19% below 6.35μ, and the volume distribution was 3% above 20.2μ (Coulter counter,
(using lOOμ aperture) was obtained.

This toner was mixed with 200/300 iron powder carrier at 10%, and tribo was measured using the Pro-Uo 7 method. The result was -62 μc.
/f was obtained. Furthermore, this toner is used as a two-component developer,
When developed with NP-5000, a good image could be obtained.

[Example 3] was added to Suspension 1 by the same operation as in Example 1.

Hydrophobic positively charged silica fine powder is silica fine powder kl, NCll2C112CH,S i (OCH,)
.

The hydrophilic negatively charged silica fine powder contained in the dispersion medium is Aerosilna 200 (manufactured by Japan Aerosil Co., Ltd.). After washing, filtering and drying, the number average diameter was 8.9μ, the number distribution was 21% below 635μ, and the volume distribution was 2% above 202μ (Coulter counter,
I used an aperture of 100 tt.

This toner was mixed with a 200/300 iron powder carrier at 10% by a plow-off method, and the result was -5.5 .mu.c/f. Further, when this toner was developed with NP-200, J, a good image could be obtained.

Procedural amendment (voluntary) Commissioner of the Patent Office Kazuo Wakasugi 1. Indication of the case 1982 Patent application No. 164574 2. Name of the invention Method for producing toner 3. Person making the amendment Relationship to the case Patent Applicant address 3-30-2 Shimomaruko, Ota-ku, Tokyo Name (+00
) Canon Co., Ltd. Representative: Ryu Kaku, Department 4, Agent address: 3-30-25 Shimomaruko, Ota-ku, Tokyo 146, Statement of the subject of amendment 6, The full text of the statement of contents of the amendment is amended as attached.

Details J: 1. Name of the invention Method for producing toner 2. Claims A hydrophobic toner material containing a chargeable silica fine powder and a polymerization initiator in a synthetic resin, 1. A method for producing a toner having 18 rods, which contains a negatively chargeable silica fine powder, which is dispersed in a dispersion tube that is hardly compatible with the above-mentioned 1-8 particles, and subjected to suspension polymerization.

3. Detailed Description of the Invention The present invention relates to a toner for developing electrostatic images, etc., and a method for producing the same.

Conventionally, toner is produced by melt-mixing colorants and other additives in a thermoplastic resin, uniformly dispersing the mixture, cooling it, and using a pulverizer or classifier to produce toner particles with a desired particle size. I've been doing it.

Although this manufacturing method can produce quite good toner, I.
There are certain limitations in the selection of materials for the glue.

That is, in a toner that is 111 processed using a pulverization method, the material must have some degree of brittleness in order to be easily pulverized. However, if the toner is too brittle, it becomes too fine and the fine powder must be canted in order to obtain a toner with an appropriate particle size distribution, which increases costs. Further, in some cases, the toner is further pulverized in the developing device of the copying machine. Also,
8. If a material with a low melting point or a material with pressure fixing property is used in order to improve fixing properties, a fusion phenomenon may occur in a crushing device or a classification device, and continuous production may not be possible.

Other requirements for the toner are that it has suitable triboelectric properties for development, that it forms an excellent image, that there is no change in performance when left standing, that it does not solidify (blocking, etc.), and that it has suitable heat resistance. Another example is that it has pressure fixing properties and that it does not contaminate the surface of the photoreceptor.

The electrostatic image developing toner obtained by suspension polymerization overcomes the drawbacks of the pulverization method. That is, grinding IX
It does not need to be brittle because it does not contain any particles, and it is spherical and has excellent fluidity, so triboelectric charging is uniform. Furthermore, by appropriately controlling polymerization or using a crosslinking agent, a toner with excellent fixing properties can be obtained.

However, it is technically difficult to perform Togane in a stably suspended system without coalescence, and to obtain fine Togane particles with a uniform r diameter distribution by Togane. When suspension polymerizing the system in water,
Suspension stabilizers are used to prevent polymer particles from coalescing as Togane progresses.

Stabilizers that are generally used as stabilizers are roughly divided into water-soluble polymers and poorly soluble fine powder inorganic compounds. , CaSO4.

BaCO3', Mgco, , Ca, q (P
O4,) 2. There are powders of CaCO2, poorly soluble salts, talc, clay, silicic acid, diatoms, inorganic polymers, and metal oxides.

In suspension polymerization, the selection of a dispersant and the stirring conditions are important for stabilizing the size of tr: r r~ and the interest rate. Low-speed stirring yields only large particles, while high-speed stirring yields small particles, but a low degree of polymerization and a drop in Togane yield are observed due to the inclusion of air. In addition, even in such high-speed IW stirring, the viscosity of the polymer gradually increases as the combination progresses, and it is not possible to prevent particles from coalescing in the mid-stage stage when the particle size tends to stick. Becomes large particles.

To prevent such a combination, Na1l, Na75O
71'9 Adding an electromagnetic substance to increase the interfacial tension, and adding glycol, glycerin, etc. to increase the viscosity of the dispersion medium have been adopted. - It was difficult to obtain. In other words, it is difficult to obtain fine particles with a particle diameter of 11 to 10 to 20, which is satisfactory as a toner. This is because, in the end, there are not enough ways to prevent coalescence.

Therefore, in the combination of a cationically polymerizable intermediate +A form and an inorganic dispersant, the interface of the polymerizable monomer Fr- becomes a cation by adding a cationic polymerizable intermediate or a poorly water-soluble organic amine compound, or The anionic polymerizable material is anionically charged due to the addition of the rI'r form.

On the other hand, the inorganic component 11i agent has a charge opposite to that of the polymerizable intermediate particles, and therefore, the surface of the polymerizable intermediate particles is completely and uniformly coated with strong ionic bonds, resulting in coalescence. prevent,
A method has been proposed for collecting fine particles having a number average diameter of about 10 to 20 μm.

However, since cationic compounds and poorly water-soluble organic amine compounds are dissolved in young aregia, it cannot be assumed that the particles will be sufficiently stable. Therefore, the anionic inorganic dispersant cannot be sufficiently attracted, and therefore the viscosity distribution cannot be said to be narrow enough. There is also a problem with charging properties.

Accordingly, one object of the present invention is to provide a method for producing a toner that solves the above drawbacks in toners produced by suspension polymerization.

That is, the present invention provides a method for producing a new negatively chargeable toner for developing electrostatic images.

Further, the present invention provides a method for producing a toner having a narrow particle size distribution and an appropriate particle size.

Furthermore, the present invention provides a method for producing a toner for developing electrostatic images that has good fluidity and excellent image quality.

The feature is that a toner material containing a hydrophobic iE chargeable fine silica powder, a synthetic resin intermediate, and an association initiator is mixed with a toner material containing a hydrophobic iE chargeable fine silica powder, a woody negatively chargeable fine silica powder, and the Q
j) Dispersing the toner in a dispersion medium that is almost incompatible with the toner itself and carrying out suspension polymerization.

That is, the hydrophobic + Jl positively charged silica fine powder has a
) When dispersed in the system, it is easily dispersed, and the amount of water in the dispersion medium is t) (3y,, Even if the system is suspended, it does not come out in the dispersion medium at all. If negatively charged silica fine powder is dispersed, IV pi
The hydrophobic positively charged silica fine powder at the J particle-interface and the woody negatively charged silica fine powder in the dispersion medium are bonded together by electrostatic attraction, and the woody negatively charged municipal silica is bonded to the surface of the suspended particles. Fine powder coats firmly and evenly. Therefore, the coalescence of suspended particles
is prevented, the particle size distribution is narrow, and fine particles can be easily obtained.

The toner prepared in this way has good fluidity, is uniformly charged, and has good image quality.

The hydrophobic iTE chargeable silica fine powder contained in the medium system is preferably 50 parts or more per 100,000 parts of the medium system, and 1
1 part of 0 to 0.1 moda is more preferred. or.

The amount of the parent-like negative-sparing silica fine powder contained in the tFI medium is likely to be more than 10 parts by 10 parts for the explant part of the body, and 5 to 5 parts of the lQ part is More preferred.

The silica fine powder used in the present invention is a general 1"
A conductive surface treatment agent and a hydrophobic surface treatment agent can be used. As an iE chargeable surface treatment agent, for example, general formula Xm
There is one represented by 5iYn. or an alkoxy group or a chloride group f.

mal or 2 or 3° Y is a hydrocarbon group having a primary to tertiary amino 7, (n; 3, 2 or 1°. Specifically, there are the following.

. , ヰ+iID′＞ヰヰヰヰヰヰID′〉ヰヰヰヰヰヰヰ〇ヰ〇ヰ〇ヰ〇ヰ〇ヰ〇ヰ〇ヰ〇〃ヰヰ〇ヰ〕ヰ〃ヰ〃ヰ〃ヰ〃ヰ〃ヰ゜゜゜グ゜グ゜グ゜ググ゜グググヰググヰグヰ゜ヰ゜ヰグ> hydrophobic surface treatment agents) to be hydrophobized to include a hydrophobic surface treatment agent, there are a silane-based coupling agent, a titanium-based coupling agent, a titanium-based coupling agent, and the like.

γ-Chloropropyltrimethoxysilane C pattern C3H6S
i(0CI(3)3 Vinyltrichlorosilane CH2=CH3iC3 Vinyltriethoxysilane CHz=9HSi(OC2Hs)3 Vinyltris(βmethoxyethoxy)silane β-(3
．． 4Epoxycyclohexyl) ethyltrimethoxysilane γ-glycidoxypropyltrimethoxysilane CH2
-CHCH20C3)1eSi(OCH3)3\1 γ-mercaptopropyltrimethoxysilane HSC3H
As a method for treating the GSi(OCH3)3 silica fine powder, any general method may be used. For example, the treatment can be carried out by stirring fine silica powder and adding a solution of the treatment agent little by little to it. Alternatively, there is a method in which a treatment agent or a solution thereof is vaporized and sprayed onto fine silica powder in a gas phase.

The treatment agent may be treated with the positively charging surface treatment agent and then treated with the hydrophobizing surface treatment agent, or both surface treatment agents may be mixed in an appropriate ratio and treated at the same time. Moreover, several types of processing agents may be used.

The wood-philic negatively chargeable silica fine powder used in the present invention includes:
Common ones are used, for example, Aerosil #1
3. O, #200. #300.

9380 (Japan Aerojirun)) can be used.

As the synthetic resin medium, the following can be applied to the present invention.

Styrene, 0-methylstyrene, m-methylstyrene,
p-methylstyrene, p-7 styrene 1/7. P-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dichlorostyrene, p-n-butylstyrene, p-tert-butylstyrene, P-n-hexylstyrene , p-n-octylstyrene, p-n-nonylstyrene, P-n-tethylstyrene, p-n-dodecylstyrene, Kasa's styrene and its derivatives; ethylenically unsaturated monomers such as ethylene, propylene, butylene, imbutylene, etc. Olefins; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl cotton; vinyl esters such as vinyl acetate, vinyl propionate, and vinyl benzoate;
Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl meccrylate, stearyl methacrylate, phenyl methacrylate, dimethyl methacrylate α-methylene aliphatic monocarboxylic acid esters such as aminoethyl, diethylamine ethyl methacrylate; acrylic methyl, acrylic ethyl, n-butyl acrylate, isobutyl acrylate, propyl acrylate, acrylic n-octyl, acrylic acid dodecyl, 2-ethylhexyl acrylate, stearyl acrylate,
Acrylic acid esters such as 2-chloroethyl acrylate and phenyl acrylate; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N -vinyl pyrrole, N-vinylcal eight tools,
N such as N-vinylintole and N-vinylpyrrolidone
- Vinyl compounds; vinylnaphthalenes; acrylic acid or methacrylic butylene derivatives such as acrylonitrile, methacrylaterile, acrylamide, etc.

In the present invention, a cationic monomer or a poorly water-soluble organic amine compound may be used simultaneously.

Cationic monomers include dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, N
Examples include monomers containing a nitrogen atom in the molecule, such as -vinyl carbutol, vinylpyridine, 2-vinylimitatool, diethylaminoethyl methacrylate, diethylaminoethyl acrylate, and Nn-butoxyacrylamide.

As poorly water-soluble organic amine compounds, the following can be applied to the present invention.

Heptylamine, octylamine, dodecylamine, dipropylamine, diisopropylamine, dibutylamine, cyamylamine, didodecylamine, triethylamine, tripropylamine, n-tetradecyldimethylamine, aniline, methylaniline, tribenzylamine, didodecylamine , etc.

By copolymerizing, these ionic skeletons become part of a small polymer and ionically bond to the silica present in the dispersion medium, thereby stabilizing the particles.

During polymerization, the following cross-linking agents are present and the polymerization is carried out.
It may also be a crosslinked polymer.

Divinylbenzene, divinylnaphthalene, divinyl ether, divinyl sulfone, diethylene glycol dimethacrylate-1, ), diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1.3- butylene glycol dimethacrylate,
1.6 hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2.2'bis(4-methacryloxydiethoxyphenyl)propane, 2.2'bis( 4-Acryloxyjethoxyphenyl)propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, dibromneopentyl glycol dimethacrylate, allyl phthalate, 1,2-propylene glycol, ■, 3 -Butanediol and other general crosslinking agents can be used as appropriate.

If these crosslinking agents are used in a large number of areas, the fixing properties will be poor. In addition, if the amount used is small, properties such as blocking resistance and # durability necessary for toner will deteriorate, and during hot roll fixing, some of the toner will not completely adhere to the paper and will stick to the roller surface, causing the next It becomes difficult to prevent the off-cent phenomenon of transfer to paper. Therefore, these crosslinking agents are preferably used in an amount of 0.001 to 15% (more preferably 0.1 to 10%) based on the total amount of monomers.

As a polymerization initiator, any suitable polymerization initiator) such as azohisin butyronitrile (810N), benzyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxy carbonate, cumene hydroperoxide, 2゜4-dichloro Monomers can be polymerized using benzoyl peroxide, lauroyl peroxide, or the like. - Generally about 0.1-10% (more preferably 0.5-5%) of initiator based on the total weight of monomers is sufficient.

In the present invention, the dispersant contains a small amount of acid, alkali,
Alcohol and a dispersion stabilizer may be used together.

Examples of dispersion stabilizers include polyvinyl alcohol,
Gelatin, methylcellulose, methylhydropropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, polyacrylic acid and their salts, starch, camarginate, heptain, casein, tricalcium phosphate, talc, barium sulfate, bentonite, water Aluminum oxide 11, ferric hydroxide, titanium hydroxide, thorium hydroxide, etc. can be used.

The stabilizer is used in an amount that stabilizes the polymerizable compound in the continuous phase, preferably about 0.1 to 10 tlr relative to the polymerizable compound.
Use within the range of weight ψ%.

Further, for fine dispersion of the inorganic dispersant, a surfactant within a range of 0.001 to 0.1% by weight based on the polymerizable compound may be used in combination. This is to promote the desired action of the dispersion stabilizer listed in Item 7. Specific examples thereof include sodium dodecylbenzenesulfonate, sodium tetradecyl sulfate, sodium beni/tadecyl sulfate, sodium octyl leiophosphate, Sodium allyl-alkyl-polyether sulfonate, Sodium oleic acid 11, Sodium laurate 11, Sodium caprylate, Sodium caprylate, Sodium caproate 11
, potassium stearate l\, calcium oleate l1.
3.3-Disulfondiphenyl J! 4,4-Diazo-his-amino-8-naphthol-6-sulfonic acid 11, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5.5-tetramethyl-triphenylmethane-4, 4-Diazo-bis-β-naphthol-
Examples include sodium disulfonate and others.

In addition, monomers that are easily soluble in wood cause emulsion polymerization in water at the same time, and the resulting suspended i11% Q'C compound is contaminated with small emulsion polymer particles, so add a water-soluble polymerization inhibitor, such as a metal salt. It is also possible to prevent emulsion polymerization in the aqueous phase. In addition, glycerin, glycol, etc. may be added to the water in order to prevent coalescence of the particles as well as the clay medium. In addition, due to the decrease in water solubility of easily soluble monomers, Na0 and K
It is also possible to use salts such as C, Na2S04, etc.

As the colorant used in the toner, commonly known dyes and pigments can be used. Furthermore, carbon blanks and magnetic materials can also be used. In particular, magnetite is preferred as the magnetic material, and surface-treated materials are also preferred.

The suspension method involves adding a monomer system in which a polymerization initiator, aggregates, and additives are uniformly dissolved or dispersed into an aqueous phase, that is, a continuous phase, containing a suspension stabilizer using an ordinary stirrer or a homogenizer. Disperse using a mixer, homogenizer, etc. The stirring speed and time are adjusted so that the medium droplets have the desired toner particle size, generally less than 30°, and then by the action of a dispersion stabilizer. (In order to maintain this state, stirring should be carried out to an extent that prevents particles from settling. The polymerization temperature is 50°C or higher, generally 70°C.
Polymerization is carried out at a temperature of ~90°C.

After the reaction is completed, the produced toner particles are collected by a suitable method such as washing, filtration, decantation, centrifugation, etc., and dried.

[Example 1] Styrene 200g Hydrophobic positively chargeable Irica fine powder 2g Azobisisobutyronitrile 4g Lione/B
/ue KL 10 g (manufactured by Toyo Ink Co., Ltd.) were uniformly mixed for about 10 minutes in a container equipped with a high shear force mixing device such as a TK Homogukiza (manufactured by Tokushu Ihata Co., Ltd.). Hydrophobic positively charged silica fine powder is H2NCH3CH2CH2Si (0CHa)! It was obtained by processing the During that time, the temperature was approximately 55℃
It was warm. During this time the pigment was uniformly dispersed in the styrene monomer.

2g (7) Aerosilna 300 (manufactured by Nippon Aerosil Co., Ltd.) fine powder was washed with 600g of water and dispersed in the above TK Homomixer, and the above slurry was put into the system kept at 70°C under stirring by the TK Homomixer, and the slurry was heated at 4000 rpm. The reaction mixture was stirred for 30 minutes at 10°C.Then, the reaction mixture was stirred using a toll blade to complete and stop the polymerization, washed with water, and dried in F3A, with a number average diameter of 10.2μ and a number distribution of 6. .65μ or less2
1%, the volume distribution was 20.2μ or more and 6% (using a coulter counter and 100μ annular char) was obtained.0 This toner was mixed with a 200/300 iron powder gear 1 noah and a 10 ratio, and then used the blow-off method. , the result of measuring tribo is -5
, 6 μc/g was obtained. Furthermore, when this Topoo was used as a two-component developer and developed with NP-5000, a good image could be obtained.

[Example 2] Styrene 200g Hydrophobic positively chargeable silica fine powder 1g2-2
'-Azobis-(2,4-dimethylvaleronitrile)4
gPa/iogen Beue L-704015
(manufactured by BASF) was subjected to suspension polymerization in the same manner as in Example 1.

Hydrophobic positively charged silica fine powder is made by converting silica fine powder into H2N-
GONH-OH,, (J(2(d(2-8t-(OC
, , H, , ) 3,
i1L aqueous negatively charged silica fine powder contains Aerosil+2
As a result of washing with water and over-drying using 00 (Japan Aerosil Co., Ltd. 9!4), the number average diameter was 9.5p, and the number distribution was 6.
．． 19 inches below 65μ, 3 inches above 20.2μ in volume distribution (
This toner was mixed with a 200/300 iron powder carrier at 10% using a blow-off method, and tribo was measured to be -6.2 μc/g. Furthermore, when this toner was used as a two-component developer and developed with NP-5000, a good 5.
It was about getting the image.

[Example 6] Styrene 180g Hydrophobic silica fine powder 2gn-butyl methacrylate 20g Benzoyl peroxide 6g BL-270
(manufactured by Titan Kogyo) 100 g was subjected to suspension polymerization in the same manner as in Example 1.

Hydrophobic positively charged silica fine powder is made by mixing silica fine powder with H2N.
CH2(j(20f(2S i (0CrH3) As a result of drying and drying, the number of pieces was 8.9μ, and the number distribution was 6.35μ or less, 21 pieces.
A volume distribution of 20.2μ or more and 2% (using Coulter counter and aperture of 100μ) was obtained.

This toner was mixed with a 200/ROOO iron powder carrier and measured by the Blow-O7 method, and the result was -5.5 μc/g. Further, when this toner was developed with NP-200J, a good image could be obtained.

Claims (1)

[Claims] A toner material containing a hydrophobic positively chargeable silica fine powder, a synthetic resin monomer, and a polymerization initiator is placed in a dispersion medium that contains a hydrophilic negatively chargeable silica fine powder and is hardly compatible with the monomers. A method for producing a toner, comprising a step of dispersing the toner in a liquid and carrying out turbidity polymerization.