JP2788634B2 - Non-magnetic one-component toner for electrostatic image development - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming a thin toner layer on a toner conveying member.
One-component developer used in a developing device having such a configuration
I do. [Prior art] Dry development method adopted in electrophotography, electrostatic recording, etc.
Uses a two-component developer consisting of toner and carrier
And one-component developer without carrier
There is a method. The former method provides a relatively stable and good image.
An image is obtained, but the carrier deteriorates and toner and
Because the mixing ratio and the like tend to fluctuate,
It is difficult to obtain images of consistent quality over
Is difficult to maintain and maintain. So, this
For those who use the latter one-component developer which does not have the above disadvantages
Expressions are getting noticed. By the way, in this method, at least one
The toner (developer) is transported by the toner transport member of
And formed on the latent image carrier by the transported toner.
A means has been adopted to visualize the electrostatic latent image
At this time, the layer thickness of the toner that is transported on the surface of the toner transport member is as small as possible.
It is said that it must be thin. Also, especially Issei
Uses a separate developer and has a high electrical resistance as its toner.
When the toner is used, the toner is charged by the developing device.
The thickness of the toner layer is significantly reduced.
I have to. If this toner layer is thick, the surface of the toner layer
Only the toner is charged, making it difficult for the entire toner layer to be charged uniformly.
Because it becomes. From such a request, the thickness of the toner layer on the toner conveying member is regulated.
Control means (toner layer thickness control means)
Has been proposed, as a typical example, a doctor blade
Use this to make this blade face the toner conveying member,
This presses the toner to be transported on the toner transport member surface
Hold down with a member (doctor blade) to control the toner layer thickness
Control. However, conventionally, as described above, the toner layer thickness
If you try to obtain an image with a developing device that has regulating means,
In, good images can be obtained, but the room gradually changes
And then, bossiness occurs. This is because toner generally
With a wide particle size distribution of 30μm, small particle size toner
First, the toner passes through the layer thickness regulating member, and the large particle size toner remains.
This is because the particle size changes depending on the application. [Purpose] The present invention aims to solve the above-mentioned problems of the prior art.
Developing a thin layer of toner on the transfer member
In electrophotography, which is designed to form high quality images
In the developing method, the toner particle size and toner
The charge amount of the toner does not change, and as a result, a product equivalent to the initial image
The purpose is to provide toner that can provide high quality images
And [Configuration] In order to achieve the above object, the configuration of the present invention employs a rotating
Toner conveying member, the toner in contact with the conveying member and the toner
Toner supply consisting of a sponge roller to supply to the material surface
A member, and the conveying member abutted on a surface of the conveying member;
Toner regulating unit that regulates the layer thickness of the toner supplied to the surface
Non-magnetic one-component toner used in a developing device having a toner material
In this, the toner measured with a coulter counter
The relationship between the number average particle diameter and the volume average particle diameter of the particles, And an electrostatic material having a volume average particle diameter of 3 to 25 μm.
This is a non-magnetic one-component toner for image development. The particle size of the toner is measured using a Coulter Counter Model T
A II (Coulter Electronics)
You. If the value of the above formula is larger than 1.2,
The particle size is selected for the supplied toner, and the toner is
Toner particle diameter that appears on the conveying member compared to the supplied toner
Is much smaller. As the development is repeated,
As toner is consumed from toner with a smaller particle size,
The particle size of the toner that appears in the
Going up. Therefore, in the initial stage and after continuous copying, the toner band
Due to the different electrical characteristics, fog and
Softness and the like occur. As a result of investigations by the present inventors, the selection of toner particle size
What happens when toner passes through the layer thickness regulating member
found. Therefore, the volume corresponding to the particle size distribution of the toner
Average particle diameter / number average particle diameter and toner appearing on the conveying member
-Average particle size of toner / volume average of toner supplied to developing device
The relationship between the uniform particle diameters (all units: μm) was investigated. The results are shown in the graph of FIG. The vertical axis in FIG. 1 is the volumetric flatness of toner appearing on the conveying member.
Equivalent particle size (μm) / Volume flat of toner supplied to developing device
The numerical value of the average particle size (μm) is shown, and the horizontal axis is supplied to the developing device.
Average particle size (μm) / number average
It shows the particle diameter (μm). Fig. 2 shows the volume-average particles of toner that appeared on the conveying member.
Diameter (μm), particle size after 10,000 continuous copies / first
The vertical axis represents the particle size of the period, and the numerical value shown on the vertical axis in FIG.
It is a graph shown on the horizontal axis. From the graphs of FIG. 1 and FIG. 2, the vertical axis of FIG.
When the value shown in the above is 0.9 or more, that is, when the
The volume average particle diameter / number average particle diameter of the supplied toner particles is
When the toner particle size on the conveying member is 1.2 or less,
Particle size after continuous copying of 000 sheets / Initial particle size is close to 1
That is, the particle size of the toner after continuous copying
It is clear that there is no change from the particle size of the toner. Further, the volume average particle diameter of the present invention is 3 to 25 μm.
Is preferable, and when it is smaller than 3 μm, the toner layer thickness is regulated.
Toner fusion occurs on the components and toner transport members,
As the amount of charge decreases, images with background stains and white stripes
You will be able to. If it is larger than 25 μm, the charge amount
Is low, so the background is stained and loose, resulting in poor sharpness.
You. In addition, prior to regulating the toner layer pressure on the conveying member surface,
Thus, a member for supplying toner to the surface of the conveying member is provided.
When using a sponge roller, the holes on the surface of the sponge
Is irregular in shape and size and has a wide particle size distribution.
When toner is used, the toner is easily
However, if a toner that satisfies the above formula is used,
It also has the advantage of being difficult to clog. Further, as the binder resin used in the toner of the present invention,
Polystyrene, poly P-chlorostyrene, polyvinyl
Homopolymer of styrene such as ruene and its substituted product: Styrene
Len-P-chlorostyrene copolymer, styrene-propylene
Styrene copolymer, styrene-vinyltoluene copolymer,
Tylene-vinyl naphthalene copolymer, styrene-acryl
Methyl luate copolymer, styrene-ethyl acrylate copolymer
Coalesce, styrene-butyl acrylate copolymer, styrene
-Octyl acrylate copolymer, styrene-methacrylic
Methyl acrylate copolymer, styrene-ethyl methacrylate copolymer
Coal, styrene-butyl methacrylate copolymer, styrene
-Α-chloromethyl methacrylate copolymer, styrene
-Acrylonitrile copolymer, styrene-vinylmethyl
Ether copolymer, styrene-vinyl ethyl ether copolymer
Polymer, styrene-vinyl methyl ketone copolymer, styrene
Len-butadiene copolymer, styrene-isoprene copolymer
Coalescence, styrene-acrylonitrile-indene copolymerization
Body, styrene-maleic acid copolymer, styrene-male
Styrene diameter copolymers such as acid ester copolymers; poly
Methyl methacrylate, polybutyl methacrylate,
Polyvinyl chloride, polyvinyl acetate, polyethylene, polyp
Ropylene, polyester, polyurethane, polyamide,
Epoxy resin, polyvinyl butyral, polyacrylic acid
Resin, rosin, modified rosin, terpene resin, phenol
Resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum tree
Fat, chlorinated paraffin, paraffin washes, etc.
It can be used alone or as a mixture. The coloring material used in the present invention includes carbon black.
Rack, lamp black, iron black, ultramarine, nigrosine dye
Ingredients, aniline blue, phthalocyanine blue, phthalocyanine
Anin Green, Hansa Yellow G, Rhodamine 6G, Les
, Calco oil blue, chrome yellow, quinakuri
Don, Benzidine Yellow, Rose Bengal, Triari
Methane dye, monoazo dye, disazo dye pigment, etc.
Use any known dye or pigment alone or in combination
I can do it. Further, the toner of the present invention may contain additives as necessary.
Is also good. As additives, for example, Teflon, stearin
Lubricants such as zinc oxide or participating cerium, silicon carbide, etc.
Abrasives, such as colloidal silica, aluminum oxide
Fluidizing agent such as minium, anti-caking agent, or
Gives conductivity such as carbon black and tin oxide
Agent or fixing aid such as low molecular weight polyethylene
is there. Next, a developing method using the toner of the present invention will be described.
Then, as shown in FIG.
The sponge roller 4 is moved by the stirring blade 5
And the toner is supplied to the sponge roller 4.
Is done. Then, the toner captured by the sponge roller 4
-The sponge roller rotates in the direction of the arrow,
The toner is conveyed to the toner conveying member 2 and rubbed, electrostatically or
The toner transport member 2 is physically attracted, and is strongly rotated in the direction of the arrow.
And a uniform toner thin layer is formed by the toner layer thickness regulating member 3.
It is formed and triboelectrically charged. Then the toner conveying member
Surface of electrostatic latent image carrier 1 in contact with or in proximity to 2
And the latent image is developed. Hereinafter, the present invention will be described specifically with reference to examples. In addition,
It is the amount (part) by weight of each component described in the examples. Example 1-1 Composition of Toner Styrene-n-butyl methacrylate resin 100 parts Polypropylene 7 parts Carbon black 11 parts Nigrosine dye 2 parts
A toner having an average particle diameter of 9.5 μm including 11.0 μm was obtained. this
2.5 parts of silicon carbide (particle size 2 μm) and 100 parts of toner
Mix and stir 0.05 parts of zinc thearate with a speed kneader.
The mixture was stirred to form a toner. This toner is used in the current state as shown in FIG.
After loading into the imaging device and performing continuous copying,
Very little change in toner particle size, initial and continuous copy unit 1
The image after 10,000 copies is good and the same quality as the initial image is obtained.
Was. Comparative Example 1-1 The volume average particle diameter of the toner of Example 1 was 10.9 μm including the number average.
Except that the particle size was 8.0 μm, the image
In the initial stage, good images were obtained, but
After 10,000 copies, the image is blurry and unclear.
Was. Example 1-2 Toner Composition Styrene-based resin 100 parts Polypropylene 5 parts Carbon black 10 parts Zinc salicylate 1.5 parts As in Example 1, a volume average diameter of 9.2 μm and a number average diameter of 8.5 μm
m was obtained. An image test was performed in the same manner as in Example 1-1.
As a result, a clear image was obtained after continuous copying
Was done. Comparative Example 1-2 Volume average diameter of toner of Example 1-2 9.5 μm Number average
An image test was performed in the same manner as in Example 1-1 except that the diameter was 7.0 μm.
Good images were obtained initially, but continuous
After 10,000 copies, the image becomes blurry and unclear.
Was. Examples 1-3 to 1-5 and Comparative Examples 1-3 to 1-5 Materials having the same compounding ratio as in Example 1-1 were kneaded to form toner particles.
The same evaluation was performed by changing only the diameter. These results
It is shown in Table 1. However, the particle size of the toner charged in the developing section with various toners
In order to obtain the initial image quality appropriately,
The contact pressure of the control member with respect to the toner
Was. As described above, the entire toner particles are formed of a material having a uniform composition.
In the following, the embodiment shown in FIG.
As shown in FIG. 3c, the outer shell (shell) is attached to the surface of the core substance (substrate).
A toner having a particle structure having a layer will be described. First, as shown in FIG. 3a, on the surface of the core material (substrate) 8
Specific description of the toner having the outer shell layer 9
I will tell. A) Content of core material The material is acrylate resin or styrene resin.
Thermoplastic transparent particles. Although this core substance can be purchased commercially,
When using the usual spray drying method, suspension polymerization method,
Granulation by solvent-based dispersion polymerization, seed emulsion polymerization, etc.
It can be manufactured by the method. If necessary, the toner particles described below
It is possible to contain colorants of raw materials, conductive agents, etc.
is there. Further, a toner having a uniform particle size as in the present invention is prepared.
Therefore, it is necessary to make the particle size distribution of this core substance uniform.
You. Considering the above manufacturing method, spray
Dry method and suspension polymerization method require classification after granulation, but organic method
Classification not required for solvent-based dispersion polymerization and seed emulsion polymerization
Become. Further, the average volume particle diameter is 3 to 25 μm. B) Contents of the outer shell (shell) layer As a method of coating the outer shell layer on the core material, first, a fine pore
Aggregation and aggregation of these fine polymer particles
Add the core substance and colorant etc. under conditions that do not cause
Disperse evenly. This dispersion is applied to a polymer of fine polymer particles.
Spray drying at a temperature above the lath transition temperature (Tg)
An outer shell layer of a polymer containing a colorant etc. on the surface of the substance
Wear. The thickness of the outer shell layer is suitably 0.5 to 5 μm. The presence of this outer shell layer determines the amount of colorant and the like used per particle.
It can greatly reduce the weight and maintain the coloring power as a toner.
There are advantages. As a polymerizable monomer for the production of small polymer particles
Any monomer can be used as long as it is a polymerizable monomer.
Dibase capable of producing phenyl-based monomers and polyester resins
Monomers such as acid or glycol may be used, but vinyl monomer
The body is preferred. Important points for the formation of this shell layer are pH change and mechanical shearing.
Maintaining the stability of the micropolymer particles against shear
And Alkyl (benzene) sulfate,
Alkyl sulfates, sodium sulfate condensates, etc.
Add a small amount of emulsifier. Also, pH control is preferred
PH 8 or more is appropriate and agitated to suppress viscosity increase
Adjustment of power is also necessary in a timely manner. The following colorants are also available:
Can be exemplified. Yellow pigment: cobalt blue, cerulean blue, arca
Libre Lake, Peacock Blue Lake, Victoria
Blue lake, metal-free phthalocyanine blue, phthalos
Anin blue, fast sky blue, indanthrene
Blue (RS, BC), Indigo, Purple pigment: Cobalt purple, Manganese purple, Faust Bio
Red B, methyl violet lake, green pigment: chrome green, zinc green, oxidized black
Mu, pyridian, emerald green, pigment grits
Green B, naphthol green B, green gold, a
Sid Green Lake, Malachite Green Lake, F
Tarocyanine green, red pigment: red iron, lead red, silver vermilion, cadmium red,
Cadmium carculy red, antimony vermilion, permane
Tread 4R, Para Red, Faise Red, Paraku
Roll Ortho Nitroaniline Red, Risor Fastos
Carlet G, Brilliant Fast Scarlet, Western
Vermilion, Brilliant Carmin BS, Permanent Red (F2
R, F4R, FRL, FRLL, F4RH), Fast Scarlet V
D, Belkan Fast Torbin B, Lisor Red, Les
-Kired (C, D), Isocin B, Brilliant
Carlet G, Lisor Rubin GK, Permanent Red
F5R, Brilliant Carmin 6B, Pigment Scarlet
3B, Bordeaux 5B, Toluidine Maroon, permanent
Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bonma
Rune Light, Bon Maroon Museum, Eosin Le
Ki, Rhodamine rake B, Rhodamine rake Y, Aliza
Lin Lake, Thioindigo Red B, Thioindigo Mar
Yellow pigments: Naphthol Yellow S, Hansa Yellow (10
g, 5G, G), cadmium yellow, yellow iron oxide, ocher,
Male yellow, lead cyanamide, calcium lead acid, Hansa yellow
(GR, A, RN, R), Pigment Yellow L, Benzine
Rho (G, GR), permanent yellow (NCG), Barca
Fast Yellow (5G, R), targe rake, key
Noline Yellow Lake, Anthrazan Yellow BGL, Black pigment: Carbon black, titanium black, etc.
A fluidizing agent, a conductive agent and the like can also be added as needed. In addition, wax, fatty acid or fatty acid metal salt,
Mosquito powder, zinc oxide powder and the like can also be added. Manufacture of aqueous dispersion of core material and fine polymer particles for outer shell below
An example is shown. Production Example 1 Production of core material-1 Styrene (vinyl monomer) 8.5 parts n-BMA (〃) 2.1 parts 2,2-azobisisobutyronitrile (initiator) 0.7 parts Polyacrylic acid (dispersion stabilizer) 3.0 parts Ethanol (solvent) While stirring with 100.0 parts, the inside of the flask is purged with dry argon gas.
And leave it for one hour while flowing a small amount of water.
The polymerization was started within. 15 minutes after heating, the liquid began to become cloudy,
The dispersion was cloudy and stable after 20 hours. When the obtained dispersion is cooled and separated by a centrifuge,
The coalesced particles settled out completely and the upper liquid was clear. Up
Remove the supernatant, add ethanol and repeat the washing with stirring.
Finally, wash with water and filter through a 1μm microfilter
Was done. The precipitate was air-dried and then dried under reduced pressure to give a 95% yield in white
A powdered polymeric core material was obtained. The particle size of this core material is
The product average diameter was 8.2 μm and the number average diameter was 7.6 μm. Production Example 2 Production of core material-2 Styrene (vinyl monomer) 9.3 parts n-BMA (〃) 4.0 parts 2,2-azobisisobutyronitrile (initiator) 0.7 parts Polyvinylpyrrolidone (dispersion stabilizer) 4.3 The same treatment as in Production Example 1 was performed with 50 parts of methanol and 57 parts of ethanol to obtain a core substance. This wick
The particle system of the substance has a volume average diameter of 8.6 μm and a number average diameter of 7.9.
μm. Production Example 3 Production of core substance-3 Styrene (vinyl monomer) 8.0 parts n-BMA (〃) 2.0 parts 2,2-azobisisobutyronitrile (initiator) 0.7 parts Polyvinylpyrrolidone (dispersion stabilizer) 2.0 The same procedure as in Production Example 1 was carried out with 100 parts of methanol to obtain a core substance. This wick
The particle diameter of the substance is 6.3 μm in volume average diameter and 5.8 in number average diameter.
μm. Production Example 4 Production of core substance-4 Water 80 ml Chloridedecane 12.3 ml Benzoyl peroxide 2.0 g Dichloroethane 9.8 ml Sodium lauryl sulfate 0.3 g was homogenized under high pressure in a two-stage homogenizer to obtain a particle size.
An emulsion of particles of about 0.1 to 0.2 μm was obtained. This d
0.65μm diameter polystyrene monodisperse seed in marjon
Latex was added. Further, water and acetone are added to the dispersion
And stirred at 40 ° C for 12 hours, followed by acetone and dichloroethane.
The solvent is evaporated under vacuum and the aqueous solution of sodium lauryl sulfate
Add distilled styrene while stirring at 30 ° C.
After stirring for 2 hours, raise the temperature to 60 ° C and start polymerization.
did. After polymerization for 20 hours, a monodisperse latex having a particle size of 2 μm
Obtained. It also contains 25 ml of water and 3.5 ml of the polystyrene particles.
4 ml of dioctanoyl peroxide, chlorodode
Emul consisting of 3 ml of can and 0.2 g of sodium lauryl sulfate
Mixed with John. Further add water and acetone while stirring at 30 ° C.
I got it. After 10 hours, remove acetone in the same manner and
Add sodium, velor and water, stir and distill styrene
Was added, and the polymerization was completed at 70 ° C. Final latex
Means volume average particle diameter is 7.1μm and number average particle diameter is 6.6μm
there were. Production Example 5 Production of aqueous dispersion of fine polymer particles for outer shell Styrene 80.0 parts 2-ethylhexyl acrylate 15.0 parts n-butyl methacrylate 5.0 parts t-butyl mercaptan 1.5 parts 1.5% sodium lauryl sulfate aqueous solution 200.0 parts ammonium persulfate (initiator) 0.2 Part Degas the mixture of the above composition, replace with nitrogen, and milk at 60 ° C for 18 hours.
An aqueous dispersion of the fine polymer was produced by chemical polymerization. The results of the formation and evaluation of the outer shell layer in the following examples
explain. Example 2-1 Aqueous dispersion (solid) of fine polymer particles prepared in Production Example 5
Water of carbon black while stirring 200 parts
Dispersion (60 parts carbon black / 300 parts water with high shear stirring
Into a more homogeneous dispersion) and sodium hydroxide
Add an aqueous solution to maintain a pH> 8 to make a stable homogeneous dispersion
Was. The core substance produced in Production Example 1 while continuing these stirrings
Into a slurry (20% solids), add 200 parts and maintain pH> 8
Reduced the viscosity rise due to coalescence of micropolymers
A uniform aqueous dispersion was obtained. This homogeneous aqueous dispersion is heated to the inlet temperature.
Spray drying at 140-160 ° C, outlet temperature 50-70 ° C, core material
A black outer shell layer was formed around. The particle diameter of this toner is 8.9 μm in volume average diameter and number average diameter
Was 8.2 μm. Silicon carbide to 100 parts of this toner
(Particle size 2.0 μm) 2.5 parts, silica (SiO _Two 0.5 part of fine powder
In addition, mix well with a speed kneader to make a toner.
Was. This toner is charged into a developing device as shown in FIG.
When continuous copying was performed, the toner particle size on the conveyance member changed.
Very few images, good at initial and after 10,000 continuous copies
There was no change. Example 2-2 An aqueous dispersion (solid content) of the fine polymer prepared in Production Example 5
30%) Copper phthalocyanine blue pigment with stirring 200g
Water dispersion (copper phthalocyanine blue 50 parts / water 300 parts
Into a homogeneous dispersion by high shear stirring) and hydroxylation
Add a sodium aqueous solution and maintain pH> 8 to maintain a stable homogeneous fraction
Sprinkled. While continuing to stir this, the core substance created in Production Example 2 was
A slurry (solid content: 20%) was prepared in the same manner as in Example 2-1.
Upon formation, a blue outer shell layer was formed around the core material. Book
As for the particle diameter of the toner, the volume average diameter is 9.5 μm, and the number average diameter is
It was 8.9 μm. Silicon carbide (particle size 2.0
μm) 3.0 parts, 0.5 part of silica fine powder and speed kneader
And mixed well to obtain a toner. This toner was evaluated in the same manner as in Example 2-1.
The image after 10,000 sheets of continuous copying was good and did not differ from the initial image. Example 2-3 An aqueous dispersion of the same amount of the fine polymer as in Example 2-1 was stirred.
Aqueous dispersion of quinacridone red pigment (quinacridone
Uniform 50 parts of Don Red pigment / 300 parts of water by high shear stirring
Dispersion) and aqueous sodium hydroxide solution.
The pH was maintained at> 8 to obtain a stable homogeneous dispersion. While continuing the stirring, the core material prepared in Production Example 3 was swirled.
Rally (solid content 20%) and prepared in the same manner as in Example 2-1
A red outer shell layer was formed around the core material. Book
The average particle diameter of the particles is 7.0 μm, and the number average diameter is 6.4 μm.
there were. Silicon toner (particle diameter 2.0 μm) 3
Parts, 0.4 part of silica fine powder and speed kneader is enough
This was mixed to form a toner. This toner was evaluated in the same manner as in Example 2-1.
Of course, the image after 10,000 copies was good and no difference from the initial
Was. Example 2-4 The monodisperse particles prepared in Production Example 4 were completely different from Example 2-1.
An outer shell layer was prepared under the same conditions. Volume average of the toner particles
The diameter was 7.8 μm, and the number average diameter was 7.3 μm. This Tona
3.0 parts of silicon carbide (particle diameter 2.0 μm), fine silica powder
Add 0.5 parts and mix thoroughly with a speed kneader
And This toner was evaluated in the same manner as in Example 2-1.
The image after 10,000 sheets of continuous copying was good and did not differ from the initial image. Comparative Example 2-1 Styrene (vinyl monomer) 8.5 parts n-BMA (〃) 2.1 parts 2,2-azobisisobutyronitrile (initiator) 0.7 parts Polyacrylic acid (dispersion stabilizer) 3.0 parts Water 200 Part The above components are stirred with a homomixer rotating at 4000 rpm.
While performing polymerization in the same manner as in Production Example 1, white powder
A polymer core material was obtained. The particle size of this core material is volume
The average diameter was 8.5 μm, and the number average diameter was 5.5 μm. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
And carbon black, using the same method as in Example 2-1.
A shell layer was created. The volume average particle diameter of the toner is 9.1.
μm and the number average diameter was 6.0 μm. This toner was mixed with additives in the same manner as in Example 2-1.
The initial image was good.
However, fogging and rubbing have occurred after continuous copying.
Was. Comparative Example 2-2 Carbon black 10 parts Styrene 70 parts n-butyl methacrylate 30 parts 2,2-azobisisobutyronitrile (initiator) 2 parts
Sodium 0.05 part, 0.75% methylcellulose aqueous solution 400
Were added and stirred. Degas the mixture and purge with nitrogen
Then, the temperature was raised to 70 ° C., and the mixture was polymerized with stirring to obtain a toner. body
The product average particle diameter is 11.0 μm and the number average diameter is 7.8 μm.
Was. This toner was mixed with additives in the same manner as in Example 2-1.
Based on the same evaluation, the initial image was good.
However, after continuous copying, fog and
Was. Examples 2-1 to 2-4 and Comparative Example 2-1
Table 2 below shows the test results of the toners 2-2. However, the toner particles of the various types
To obtain an initial image appropriately according to the diameter, the toner layer
Adjust the pressure on the toner conveying member of
Was. Next, an outer shell layer 9 is applied to the surface of the core material 8 shown in FIG. 3b.
First, a toner having an outer coating layer 10 on its surface is described.
I will tell. First, the core material 8 and the outer shell layer 9 are formed as shown in FIG.
The same as the toner particles. Outside the toner shown in FIG. 3b
The side covering layer 10 will be described. C) Contents of the outer coating layer When the colorant particles dispersed in the outer shell material are 1.0 μm or more.
Or smaller, but compatible with the outer shell polymer
If the performance is poor,
The coloring agent particles are easily detached from the outer shell. Therefore, the outer shell
By providing this outer coating layer on the outside, the above-mentioned drawback is improved.
I can do better. As a method of providing this outer coating layer on the outer side of the outer shell, an outer layer is used.
The method may be the same as the method for forming the shell, and the fraction of the fine polymer particles may be used.
Does not cause aggregation or coalescence of these fine polymer particles in the liquid dispersion
Under the conditions, the shell-retaining particles are
Disperse uniformly in the dispersion. This dispersion is used as a fine polymer
Spray drying at a temperature above the glass transition temperature (Tg) of the particles
As a result, an outer coating layer of a polymer is formed outside the outer shell layer. The thickness of the outer coating layer is suitably about 0.5 to 3 μm.
You. Small polymer particles are the same as those used for the outer shell.
Such materials and methods of preparation are preferred. Hereinafter, the formation and evaluation of the outer shell layer and the outer coating layer in Examples will be described.
The result of the price will be described. Example 3-1 First, a core material was prepared under the same conditions as in the method described in Example 2-1.
To form toner particles having an outer shell layer on the surface of the toner. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
(Sodium hydroxide 30%)
The solution was added to maintain a pH> 8 to obtain a stable homogeneous dispersion. While continuing to stir this liquid, the black outer shell layer created earlier
Particles (solid content: 20%), add 200 parts and add p
Viscosity increase due to cohesion and coalescence of small polymers while maintaining H> 8
A homogeneous aqueous dispersion in which the water content was suppressed was obtained. This uniform water dispersion
Spray drying of liquid at inlet temperature 140-160 ° C, outlet temperature 50-70 ° C
Thus, an outer coating layer was formed. This toner has a volume average diameter of 9.8 μm and a number average diameter of 8.8 μm.
m. Silicon carbide (particle size)
2.0 parts) 2.5 parts, silica (SiO _Two ) Add 0.5 parts of fine powder
The mixture was sufficiently mixed and stirred with a speed kneader to obtain a toner. This toner is charged into a developing device as shown in FIG.
When continuous copying was performed, the toner particle size on the conveyance member changed.
Very few images, good at initial and after 40,000 continuous copies
There was no change. Example 3-2 An aqueous dispersion (solid) of the fine polymer particles prepared in Production Example 5
Copper phthalocyanine bull while stirring 200 parts
-Water dispersion of pigment (copper phthalocyanine blue 120 parts / water 4
00 parts were made into a homogeneous dispersion by high shear stirring) and
Add aqueous sodium hydroxide solution to maintain pH> 8 and stable
A homogeneous dispersion was obtained. While continuing to stir this, the core substance created in Production Example 2 was
Add 200 parts of slurry (solid content 20%) and keep pH> 8
Uniform with reduced viscosity increase due to aggregation and coalescence of small polymers
An aqueous dispersion was obtained. This aqueous dispersion is heated at an inlet temperature of 140 to 160
Spray drying at 50 ° C, outlet temperature 50 ~ 70 ° C, blue around core material
An outer shell layer of color was created. The volume average diameter of this toner is 9.5μ
m, and the number average diameter was 8.9 μm. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
(Sodium hydroxide 30%)
The solution was added to maintain a pH> 8 to obtain a stable homogeneous dispersion. While continuing to stir this liquid, the blue outer shell layer created earlier
200 parts of particles with slurry (solid content 20%)
> 8 to increase the viscosity due to coalescence of micropolymers
A suppressed uniform aqueous dispersion was obtained. This homogeneous aqueous dispersion
Spray drying at inlet temperature 140-160 ° C, outlet temperature 50-70 ° C
Thus, an outer coating layer was formed. This toner has a volume average diameter of 10.0 μm and a number average diameter of 9.2.
μm. Silicon carbide (particles)
2.5 parts of 2.0 μm diameter, silica (SiO _Two ) Add 0.5 parts of fine powder
The toner was sufficiently mixed and stirred with a speed kneader to obtain a toner. This toner was evaluated in the same manner as in Example 3-1.
Of course, the image after 40,000 sheets of continuous copying is good and no difference from the initial
Was. Example 3-3 An aqueous dispersion (solid) of the fine polymer particles prepared in Production Example 5
Quinacridone pigment water while stirring 200 parts
Dispersion (150 parts of quinacridone pigment / 400 parts of water with high shear stirring
PH> 8
Was maintained to obtain a stable uniform dispersion. While continuing to stir this, the core substance created in Production Example 3 was
Add 200 parts slurry (20% solids) and keep pH> 8
Uniform with reduced viscosity increase due to aggregation and coalescence of small polymers
An aqueous dispersion was obtained. The uniform aqueous dispersion is treated at an inlet temperature of 14
Spray drying at 0-160 ° C, outlet temperature 50-70 ° C,
A red outer shell layer was formed. The volume average diameter of this toner is 7.
2 μm and the number average diameter was 6.7 μm. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
(Sodium hydroxide 30%)
The solution was added to maintain a pH> 8 to obtain a stable homogeneous dispersion. The red shell layer created earlier while continuing to stir this solution
Particles having a solid content of 20% and add 200 parts
Viscosity increase due to cohesion and coalescence of small polymers while maintaining H> 8
A homogeneous aqueous dispersion in which the water content was suppressed was obtained. This uniform water dispersion
Spray drying of liquid at inlet temperature 140-160 ° C, outlet temperature 50-70 ° C
Thus, an outer coating layer was formed. This toner has a volume average diameter of 7.8 μm and a number average diameter of 7.1 μm
m. Silicon carbide (particle size)
2.0 parts) 2.5 parts, silica (SiO _Two ) Add 0.5 parts of fine powder
The mixture was sufficiently mixed and stirred with a speed kneader to obtain a toner. This toner was evaluated in the same manner as in Example 3-1.
Of course, the image after 40,000 sheets of continuous copying is good and no difference from the initial
Was. Example 3-4 The core material prepared in Production Example 4 was compared with Example 3-1.
Under the same conditions, a shell layer and an outer coating layer were formed. Book
The volume average diameter of the toner particles is 9.0 μm and the number average diameter is 8.5 μm
Met. The same amount of additive as in Example 1 was added to the toner particles.
Evaluated in the same way, the image after 40,000 consecutive copies is also the first
It was detailed without any difference. Next, on the surface of the core material 8 shown in FIG.
Explanation of toner with outer layer (II) 11 on its surface
I do. First, the core material 8 and the outer shell layer 9 are formed as shown in FIG.
The same as the toner particles. Outside the toner shown in FIG. 3c
The shell layer (II) 11 will be described. D) Contents of the outer shell (shell) layer (II)
It is preferable to add a control agent.
It has been confirmed that it occurs only on the very surface, and charging is controlled inside.
There is no need to contain any agent. Therefore, only the toner surface
Had only an outer shell layer in an attempt to add a charge control agent to
It can be mechanically attached by mixing with toner.
However, in this case, the adhesion to the outer shell layer is poor, and
Detachment due to agitation in the device also adheres to members inside the device and toner
Of the toner has low chargeability. Therefore, in the present invention, the outer shell (shell) layer (II) is provided,
Prevents desorption of the charge control agent from the shell layer. Outer shell (II)
The formation method may be the same as the case of forming the outer shell layer.
Agglomeration and coalescence of the fine polymer particles into a dispersion of limmer particles
Under the conditions that do not cause the addition of the core substance and the charge control agent, etc.
And evenly disperse. This dispersion is made up of fine polymer particles.
Spray drying at temperatures above the glass transition temperature (Tg)
Outer shell layer of polymer containing charge control agent etc. on the surface of shell layer
(II) is possible. The thickness of the outer shell layer (II) is 0.1 to 3 μm.
m is appropriate. What is involved in the preparation of small polymer particles?
It is the same as that shown in the outer shell layer. The outer shell layer (II)
The important points in creating the same are the same as those shown in the outer layer.
is there. As the charge control agent, any known charge control agent may be used.
Nigrosine dye, quaternary ammonium salt
Compounds, triphenylmethane dyes, etc.
Examples include metal-containing complexes and salts.
is not. Results of outer layer formation and evaluation by the following examples
Will be described. Example 4-1 An aqueous dispersion (solid) of the fine polymer particles prepared in Production Example 5
Water of carbon black while stirring 200 parts
Dispersion (60 parts carbon black / 300 parts water with high shear stirring
And aqueous sodium hydroxide)
The solution was added to maintain a pH> 8 to form a stable homogeneous dispersion. While continuing to stir this, the core material created in Production Example 1 was
Slurry (20% solids), add 200 parts and keep pH> 8
To minimize the increase in viscosity due to coalescence of micropolymers.
A uniform aqueous dispersion was obtained. Inlet temperature of this uniform aqueous dispersion
Spray drying at 140-160 ° C, outlet temperature 50-70 ° C,
A black outer shell layer was formed around it. The particles have a volume average diameter of 8.9 μm and a number average diameter.
Was 8.2 μm. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
(Solid content 30%) of Nigrosine dye while stirring 100 parts
Water dispersion (20 parts Nigrosine / 200 parts water by high shear stirring)
Into a homogeneous dispersion) and aqueous sodium hydroxide solution
To maintain a pH> 8 to obtain a stable homogeneous dispersion. Of this
While continuing the stirring, the particles with the black outer shell layer
Slurry (solid content 20%), add 300 parts and keep pH> 8
To minimize the increase in viscosity due to coalescence of micropolymers.
A uniform aqueous dispersion was obtained. Inlet temperature of this uniform aqueous dispersion
Spray drying at 140-160 ° C, outlet temperature 50-70 ° C, charge control
An outer shell layer (II) containing the agent was formed around the outer shell layer. The volume average diameter of the toner particles is 9.3 μm, and the number average diameter is
It was 8.6 μm. Silicon carbide to 100 parts of this toner
(Particle size 2.0 μm) 2.5 parts, silica (SiO _Two ) 0.1 part of fine powder
In addition, mix well with a speed kneader to make a toner.
Was. This toner is charged into a developing device as shown in FIG.
When continuous copying was performed, the toner particle size on the conveyance member changed.
Very few images, good at initial and after 40,000 continuous copies
There was no change. Example 4-2 An aqueous dispersion (solid) of the fine polymer particles prepared in Production Example 5
While stirring 200 parts of copper phthalocyanine
Aqueous dispersion of roux pigment (copper phthalocyanine blue 50 parts / water
300 parts made into a homogeneous dispersion by high shear stirring) and
And sodium hydroxide solution to maintain pH> 8 and stable
A homogeneous dispersion was obtained. While continuing to stir this, the core substance created in Production Example 2 was
Slurry (solid content 20%), add 200 parts and keep pH> 8
To minimize the increase in viscosity due to coalescence of micropolymers.
A uniform aqueous dispersion was obtained. Inlet temperature of this uniform aqueous dispersion
Spray drying at 140-160 ° C, outlet temperature 50-70 ° C,
A blue outer shell layer was formed around it. The volume average diameter of the particles is 9.5 μm, the number average diameter is 8.9 μm
Met. Further, an aqueous dispersion of fine polymer particles prepared in Production Example 5
(Solid content 30%) zinc salicylate while stirring 100 parts
Water dispersion (zinc salicylate 20 parts / water 200 parts with high shear)
Into a homogeneous dispersion by stirring) and sodium hydroxide
Aqueous solution to maintain stable pH> 8
did. Hold the black shell layer created earlier while continuing to stir this.
Particles into a slurry (solid content 20%), add 300 parts and pH>
8 to suppress increase in viscosity due to coalescence of fine polymers
A controlled and uniform aqueous dispersion was obtained. This uniform aqueous dispersion
Spray-dried and loaded at an inlet temperature of 140 to 160 ° C and an outlet temperature of 50 to 70 ° C
An outer shell layer (II) containing an electric control agent is formed around the outer shell layer.
Was. The volume average diameter of the toner particles is 9.9 μm, and the number average diameter is
It was 9.3 μm. Silicon carbide to 100 parts of this toner
(Particle size 2.0 μm) 2.5 parts, silica (SiO _Two ) 0.1 part of fine powder
In addition, mix well with a speed kneader to form a toner.
Was. This toner was evaluated in the same manner as in Example 1.
The image after 40,000 copies was also good and did not differ from the initial image. Example 4-3 An aqueous dispersion (solids) of the fine polymer particles prepared in Production Example 5
Quinacridone red face while stirring 200 parts)
Aqueous dispersion of quinacridone red pigment (50 parts / water 300 parts)
Into a homogeneous dispersion by high shear stirring, and
Stable and uniform by adding sodium chloride aqueous solution and maintaining pH> 8
A dispersion was obtained. While continuing to stir this, the core substance created in Production Example 3 was
Slurry (20% solids), add 200 parts and keep pH> 8
To minimize the increase in viscosity due to coalescence of micropolymers.
A uniform aqueous dispersion was obtained. Inlet temperature of this uniform aqueous dispersion
Spray drying at 140-160 ° C, outlet temperature 50-70 ° C,
A red outer shell layer was formed around it. The volume average diameter of the particles is 7.0 μm,
The average was 6.4 μm. Further, the outer shell layer (II) was applied to the particles in the same manner as in Example 2.
It was created. The volume average diameter of the toner particles is 7.5 μm,
The number average diameter was 6.9 μm. 100 parts by weight of this toner
2.5 parts of silicon carbide (particle size 2.0 μm) and silica (SiO _Two )
Add 0.1 part of fine powder and mix well with a speed kneader
Was used as a toner. This toner was evaluated in the same manner as in Example 1.
The image after 40,000 copies of the subsequent copy was also good and did not differ from the initial image. Example 4-4 Exactly the same as Example 1 for the core substance prepared in Production Example 4.
Under the conditions, an outer shell layer and an outer shell layer (II) were prepared. This toner particle
The volume average diameter of the particles was 8.5 μm and the number average diameter was 8.0 μm.
Was. The same amount of additive as in Example 4-1 was added to the toner particles.
When the same evaluation was performed, the image after 40,000 consecutive copies was also the first.
It was clear with no difference from the period. [Effect] As described above, by using the toner of the present invention,
Thus, an image equivalent to the initial image can be obtained even after continuous copying.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing a relationship between a volume average particle diameter / number average particle diameter of toner and a toner particle diameter appearing on a conveying member / toner particle diameter supplied to a developing device. Is a graph showing the relationship between the initial particle diameter after continuous copying of 10,000 sheets, with respect to the toner particle diameter appearing on the initial conveying member / the toner particle diameter supplied to the developing device and the toner particle diameter appearing on the conveying member, 3a to 3c are explanatory diagrams showing the configuration of toner particles composed of a core substance and an outer shell layer, and are explanatory diagrams showing an outline of the configuration of a developing device using the toner of the present invention shown in FIG. DESCRIPTION OF SYMBOLS 1 ... Electrostatic latent image carrier, 2 ... Toner conveying member, 3 ... Toner layer thickness regulating member, 4 ... Sponge roller, 5 ... Stirring blade, 6 ... Toner, 7 ... Toner tank, 8 ... core material, 9 ... outer shell layer, 10 ... outer coating layer, 11 ... outer shell layer (II).

Continued on the front page (72) Inventor Koji Tanaka 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Co., Ltd. (72) Inventor Tomoge Hagiwara 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company In Ricoh Company (72) Inventor Kimitoshi Yamaguchi 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh (72) Inventor Hiroshi Yamashita 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company In Ricoh (56) References JP-A-63-38947 (JP, A) JP-A-61-130962 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 9/08

Claims (1)

(57) [Claims] A rotating toner transport member, a toner supply member including a sponge roller that contacts the transport member and supplies toner to the surface of the transport member, and a toner that is in contact with the transport member surface and is supplied to the transport member surface In a non-magnetic one-component toner used in a developing device having a toner regulating member that regulates the layer thickness of the toner, the relationship between the number average particle diameter and the volume average particle diameter of the toner particles measured by a Coulter counter is And a volume average particle diameter of from 3 to 25 μm.