JP2675974B2 - Magnetic toner for developing electrostatic images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] The present invention relates to electrophotography, electrostatic recording, etc.
The present invention relates to a novel magnetic toner for developing an electrostatic image. [0002] In electrophotography, cadmium sulfide is used.
Light such as aluminum, polyvinylcarbazole, selenium, and zinc oxide
First, an electrostatic latent image is formed by utilizing the property of the conductor. An example
For example, charge is uniformly applied on the photoconductor layer, and image exposure is performed.
To form an electrostatic latent image, and then what is the charge of the electrostatic latent image?
Develop with oppositely charged toner powder and
Then, it is transferred to the transfer sheet and fixed. Of these, transfer
If the device has a
Remove the remaining toner on the photoconductor and repeat the photoconductor
It is usually used. Remaining toner on the photoconductor
As a removal method, a blade cleaning method or a
Brush cleaning method, magnetic brush cleaning
For example, by connecting the cleaning member to the photoconductor
Is common. In this case, the cleaning member
Since it is pressed against the photoconductor with pressure, repeat use
The toner may be scratched or the toner may stick
May occur. For example, JP-A-48-47345
In this publication, the phenomenon that this toner adheres to the photoconductor is described.
To avoid friction-reducing substances and abrasive substances in the toner,
It has been proposed to add both. This method is
It is effective in avoiding the toner sticking phenomenon, but
I have a problem. That is, the toner sticking phenomenon can be avoided.
Friction-reducing substances can be added at frequent intervals for repeated use.
Addition of paper dust or ozone that is generated or adheres to the surface of the photoconductor
It becomes difficult to remove low electrical resistance substances such as
In addition, the latent image on the photoconductor has a low electrical resistance in a high temperature and high humidity environment.
The problem is that it is significantly impaired by the anti-substance.
In addition, the addition amount of each of the friction reducing substance and the polishing substance is delicate.
And it is difficult to obtain a toner having stable characteristics.
There is a problem. [0004] SUMMARY OF THE INVENTION The present invention is as described above.
This was achieved as a result of intensive research in consideration of the situation. An object of the present invention is to prevent static damage to the photoreceptor.
It is to provide a magnetic toner for developing a charge image. Another object of the present invention is to provide a high temperature and high humidity environment.
Magnetic toner for developing electrostatic images that does not disturb latent images
Is to provide. Still another object of the present invention is to transfer the toner on the photoreceptor.
Electrostatic charge with easy cleaning of the residual magnetic toner and polishing ability
An object is to provide a magnetic toner for image development. Another object of the present invention is to provide a magnetic member for a photosensitive member.
Prevents adhesion and fusion of the toner and prevents streaks on the copied image.
Magnetic toner for electrostatic image development that does not cause spot-like contamination
To provide. Still another object of the present invention is to develop a developing film.
Prevents contamination of the image and prevents the image density from decreasing during durability
An object is to provide a magnetic toner for developing an electrostatic image. [0010] [Means and Actions for Solving the Problems]
Akira has a weight average molecular weight of 3,000 to 80,000,
And contains 5-60 wt% boiling point n-hexane extract
1 to 1 of polyalkylene based on 100 parts by weight of the resin component
0 parts by weight and 10 to 70% by weight of magnetic powder (to
(Based on the weight of toner)
Silicone treated with silicone oil containing amine
Has fine powder and has a dynamic friction coefficient of 0.20 to 0.50
And a magnetic toner for developing an electrostatic charge image
You. The magnetic toner of the present invention has a dynamic friction coefficient
As shown in the figure, the magnetic toner particles themselves have moderate abrasiveness.
Therefore, it has an appropriate surface hardness due to its own polishing ability.
Do not scratch the photoconductor you have that may affect the image.
Somehow magnetic toner remaining on the photoconductor after transfer, low resistance material
Also, paper dust and the like can be removed. Further, the dynamic friction coefficient of the magnetic toner of the present invention
And the surface hardness of the photoconductor
Proper non-adhesiveness in the interaction of photoconductors with magnetic toners
Is realized, and the magnetic toner that remains on the transfer without damaging the photoreceptor.
It is possible to remove the
Adhesion of strong magnetic toner to body and fusion of magnetic toner
Is presumed to be prevented. Further, a photosensitive material having this specific surface hardness
Body and magnetic toner with specific dynamic friction coefficient
Addition is added to assist polishing or lubricity.
It is possible to make the amount of additives virtually zero or very small.
Magnetic toner or additives that can be formed on the photoreceptor
It also has an effective effect in preventing filming. Soshi
The magnetic toner having abrasiveness of the present invention is a developing sleeve.
Prevents sleeve contamination when in contact with a durable image density
Also has the effect of stabilizing. The magnetic toner of the present invention is measured by the following measuring method.
0.20 to 0.50, preferably 0.2
It is preferable to have a dynamic friction coefficient of 0 to 0.45. like this
The magnetic toner of the present invention having a specific friction coefficient is a photoreceptor
To the magnetic toner particles themselves without damaging them
Fully exhibiting the polishing ability. Therefore chestnut
In the corner blade, low resistance substances
Of the latent image due to contaminants as the toner is easily removed.
Disturbance and cleaning failure can be prevented. Large coefficient of friction
If it is too hard, it may damage the surface of the photoconductor and
Adhesion with the photoconductor increases and sufficient cleaning is achieved.
Not done. On the other hand, if it is too small, the polishing effect is insufficient.
Minutes. When the magnetic toner has the above coefficient of friction, it is magnetic.
When the toner and the developing sleeve are in proper contact, the magnetic toner
-The sleeve will not be contaminated due to
The durable image density is stabilized even in a high humidity environment. The friction coefficient according to the present invention is measured as follows.
It is defined as the value measured by the method. That is, an example
For example, HEIDON14 type surface measuring machine (manufactured by Shinto Chemical Co., Ltd.)
Hardness equivalent to the surface layer of the OPC photoconductor on the sample stand
20 g of styrene-methylmethacrylate resin flat membrane
Is fixed. Polyurea kept at an angle of 45 ° on this flat film
Tan rubber blade (thickness 2 mm x width 10 mm x length 5
0mm) with a load of 100g from above,
It was moved at a speed of 50 mm / min and placed on a flat membrane.
50 g of magnetic toner is uniformly applied on the flat film. Next, the magnetic toner layer is directly made of quartz.
A vertical load of 100 g is applied through a disk with a diameter of 15 mm,
Move the sample stage at a speed of 50 mm / min to
The static / dynamic friction resistance force that occurs sometimes is measured to determine the static / dynamic friction coefficient.
Calculate the number. Magnetic toner giving a coefficient of friction in the above range
Magnetic powder and polyalkylene are especially important as constituents of
is there. The inventors of the present invention have identified a specific range as described below.
Has the weight average molecular weight of the box and boiling point n-hexane extraction
Polyalkylene containing a certain amount of minutes is preferable
I found that. In particular, the value of the boiling point n-hexane extract is
There is a strong correlation with the friction coefficient of the magnetic toner of the present invention.
By controlling the boiling point n-hexane extract
Can eliminate various problems related to cleaning.
That is, the present invention has been achieved and the present invention has been achieved. Polya to be contained in the magnetic toner of the present invention
As ruylene, the weight average molecular weight Mw is 3000 to 8
000 and boiling point n-hexane extractables 5 to 60%
What is contained is used, and especially the above effects
In order to volatilize, the weight average molecular weight Mw is 5,000 to
60000, and the boiling point n-hexane extract is 10
It is preferable that the content is up to 45%. Examples of the above polyalkylene include polyethylene.
Len, polypropylene, polybutene, polyhexene, etc.
Homopolymer, ethylene-propylene copolymer, ethylene
Copolymers such as len-butene copolymers,
Ternary copolymers such as sen, and their thermal metabolites
It can be illustrated. In particular, polypropylene and its heat-modified products
Is preferred. 100 parts of these polyalkylene resin components
1 to 20 parts by weight, preferably 1 to 10 parts by weight
It is better to add parts by weight. Because this poly
Magnetic toner particles containing alkylene
Surface roughness and hardness are moderate, and proper polishing
The magnetic properties can be retained in the magnetic toner.
You. As a result, the magnetic toner of the present invention damages the photoreceptor.
Without disturbing the latent image disturbances on the photoconductor
This is because it is possible to prevent image contamination due to adhered substances. Various methods can be used to measure the weight average molecular weight Mw.
There is a slight difference in value. Therefore, the present invention
Is determined to be the value measured by the following measuring method.
Mean That is, gel permeation chromatography
According to the graphography (GPC), the temperature is 135 ° C., the solvent o-
Dichlorobenzene (0.1% ionol added), measurement
4 with a flow rate of 1.0 ml / min and a concentration of 0.1 wt%
Inject 00 μl. Monodisperse when measuring the molecular weight of a sample
Use a calibration curve created using polystyrene standard samples.
You. The column is not limited in the measurement.
However, for example, A-80M manufactured by Shoredex may be exemplified.
You. Further, the boiling point n-hexane extractable component in the present invention
Is a polymer portion soluble in boiling point n-hexane.
It is a ratio and is measured as follows. That is, the constant weight of the polymer (W₁g)
Using a Soxhlet extractor, etc.
The boiling point n-hexane soluble component in the polymer of
Next, weigh the sample that is left unextracted after drying.
(W_Twog). The amount of extractables is calculated by the formula (W₁ -W_Two / W₁ ) ×
Calculated using 100 (%). The magnetic toner of the present invention contains an amine in the side chain.
Silica fine powder treated with silicone oil has
It is attached. This makes the surface of the photoconductor even better
It is maintained even during endurance. The magnetic toner of the present invention was prepared by the nitrogen adsorption method.
BET specific surface area of 0.5 to 500 m²  / G, especially 50
~ 400m²  / G silica fine powder is good to add
No. Because, by adding such silica fine powder,
This is because the above-mentioned disturbance of the latent image is reduced. It is this
Such fine silica powder has a large specific surface area
In addition, the low resistance material that adheres to the drum mentioned above is
It seems to be removed by adsorption or adhesion. The silica fine powder referred to here is Si-O-Si.
Fine powder having a bond, manufactured by a dry method
And those manufactured by the wet method are also included. Siri
A method for producing fine powder by a wet method is a conventionally known method.
Various methods can be applied. For example, sodium silicate acid
Decomposition by the general reaction formula, Na_Two OxSiO_Two + HCl + H_Two O → SiO_Two ・ N
H_Two O + NaCl Others (reaction formulas are omitted below), sodium silicate
Decomposition by monia salts or alkali salts, sodium silicate
Alkaline earth metal silicate was produced from strontium.
After that, the method of decomposing with acid to make silicic acid, sodium silicate
Method of converting liquid to silicic acid by ion exchange resin, natural silica
There is a method using an acid or a silicate. The silica fine powder referred to here is anhydrous dioxide.
Silicon (silica), others, aluminum silicate, silica
Sodium acid, potassium silicate, magnesium silicate,
Any silicate such as zinc silicate can be applied. That
The particle size is within the range of 0.01 to 2μ as the average primary particle size.
Is preferred. Also, 85% by weight or more of S
iO_Two Those containing are preferred. The silica fine powder obtained by the dry method is a so-called dry powder.
Formula silica, or what is called fumed silica,
It is manufactured by a conventionally known technique. example
Pyrolysis of silicon tetrachloride gas in oxyhydrogen flame
It is a method that uses reactions, and the basic reaction formula is as follows.
It is. [0031] SiCl_Four + 2H_Two + O_Two → SiO_Two +4 HCl In this manufacturing process, for example, aluminum chloride,
Alternatively, use another metal halide such as titanium chloride for silicon
Silica and other metals can be used with rogen compounds
It is also possible to obtain a composite fine powder of oxide, and in the present invention,
They are also included. The particle size is 0.0 as the average primary particle size.
It is preferably in the range of 01 to 2μ, and particularly preferably
Uses fine silica powder within the range of 0.002-0.2μ
Good to do. These fine silica powders have amines in the chain.
It has been treated with silicone oil
If the toner is a positively charged magnetic toner, the positively charged toner
It is preferable to use a fine powder of Rica, which has a negative charging property.
For silica, use negatively charged fine silica powder.
Is preferred. Further, the positively or negatively charged silica fine powder
Is the absolute value of its tribo charge, measured by
10 | μc / g or more is preferable, and especially | 30 | μc / g
Above is good. The following describes positively charged silica as an example.
I will tell. Here, the positively charged silica fine powder is as follows.
Is defined as That is, a ring at 25 ° C and 50 to 60% RH
2 to 30g of fine silica powder left overnight in the precinct
Main mesh size is 0 mesh, not coated with resin
Carrier iron powder (for example, EFV200 / 30 manufactured by Nippon Iron Powder Co., Ltd.
0) 98 g and a volume of about 200 cc under the above environment
Hold it fully in an aluminum pot (hold it up and down
Shake about 50 times) and mix, 400 mesh
Using an aluminum cell with a clean
Measurement of triboelectric charge of fine silica powder by blow-off method
I do. Tribo charge measured by this method becomes positive
Fine silica powder is defined as positively charged fine silica powder. Obtaining such positively charged silica fine powder
In order to treat with silicone oil containing amine
It is good to As such a treating agent, for example, the following formula
Use modified silicone oil that has amine in the side chain of
Can be. [0036] [Outside 1] (Where R₁ Is hydrogen, alkyl group, aryl group or ar
A oxy group;_Two Is an alkylene group or phenylene
R represents a group_Three , R_Four Is hydrogen, an alkyl group or aryl
Represents a hydroxyl group. However, the above-mentioned alkyl group, aryl group,
The alkylene group and phenylene group may contain amine.
And substituents such as halogen within the range that does not impair the chargeability.
May have. ) Examples of such silicone oil include
There is [0037] [Outside 2]The amine equivalent in the present invention means
Equivalent weight per min (g / eqiv), the molecular weight is 1
It is the value divided by the number of amines per molecule. Preferred positively or negatively charged silica
The fine powder has a hydrophobicity measured by the methanol titration test.
It is preferable that the degree of conversion shows a value in the range of 30 to 80. The methanol titration test was conducted on a hydrophobized surface.
To confirm the degree of hydrophobicity of silica fine powder
It is a test. Evaluation of hydrophobicity of treated silica fine powder
“Methanol drops” as defined herein to
The "constant test" is performed as follows. Test silica fine powder 0.2 g
To 50 ml of water in a 250 ml Erlenmeyer flask
I do. From the burette, add methanol to remove all the silica.
Titrate until moistened. At this time, the solution in the flask is
Stir constantly with a natural stirrer. The end point is Siri
Observed by suspending the entire amount of fine powder in liquid
And the degree of hydrophobicity is methanol and water when the end point is reached.
Expressed as the percentage of methanol in the liquid mixture of
You. The applied amount of these silica fine powders is magnetic.
Of 0.01 to 20% by weight based on the weight of the toner
Preferably, particularly preferably when 0.1 to 3% by weight is added
It exhibits positive or negative chargeability with excellent stability.
The preferred mode of addition is magnetic toner.
0.01 to 3% by weight of treated silica fines
The powder is attached to the surface of the magnetic toner particles.
Is good. The binder resin for the magnetic toner of the present invention includes:
Polystyrene, poly-p-chlorostyrene, polyvinyl
Monopolymers of styrene such as ruene and its substitution products;
Len-p-chlorostyrene copolymer, styrene-propyrene
Ethylene copolymer, styrene-vinyltoluene copolymer,
Tylene-vinylnaphthalene copolymer, styrene-acrylic
Methyl acetate copolymer, styrene-ethyl acrylate copolymer
Coal, styrene-butyl acrylate copolymer, styrene
-Octyl acrylate copolymer, styrene-methacrylic acid
Methyl acrylate copolymer, styrene-ethyl methacrylate
Copolymer, styrene-butyl methacrylate copolymer,
Styrene-α-methyl chloromethacrylate copolymer, su
Tylene-acrylonitrile copolymer, styrene-vinyl
Methyl ether copolymer, styrene-vinyl ethyl ester
Ter copolymer, styrene-vinyl methyl ketone copolymer
Polymer, styrene-butadiene copolymer, styrene-isoprene
Rene copolymer, styrene-acrylonitrile-indene
Copolymer, styrene-maleic acid copolymer, styrene-
Styrene-based copolymers such as maleic acid ester copolymers
Body; polymethylmethacrylate, polybutylmethacrylate
Sheet, polyvinyl chloride, polyvinyl acetate, polyethylene
Resin, polypropylene, polyester, polyurethane,
Liamide, epoxy resin, polyvinyl butyral, poly
Amide, polyacrylic acid resin, rosin, modified rosin,
Terpene resin, phenolic resin, aliphatic or alicyclic carbonization
Hydrogen resin, aromatic petroleum resin, chlorinated paraffin, para
Fin wax, carnauba wax, etc. alone or mixed
Can be used in combination. If necessary, the magnetic toner may include a lubricant and a conductive agent.
For example, polytetrafluor
Of polyethylene powder, polyvinylidene fluoride powder, higher fatty acids
Metal salts, carbon black, conductive tin oxide, etc. are added.
You may Further, the magnetic toner of the present invention has a volume resistivity
Is 10^TenΩcm or more, especially 10¹²Ωcm or more
good. The volume resistivity referred to here is 100 for magnetic toner.
kg / cm^Two Molding at a pressure of 100 V / cm
Field is applied and converted from the current value 1 minute after application
Defined as a value. The magnetic toner of the present invention contains magnetic powder.
Have. The magnetic powder is placed in a magnetic field
A magnetized material is used, such as iron, cobalt, or nickel.
Which ferromagnetic metal powder or magnetite, γ-Fe
_Two O_Three , Compounds such as ferrite and their alloys
You. In particular, the cleaning effect and good developing property
BE is preferably produced by a nitrogen adsorption method in order to exert the effect.
T specific surface area is 2 to 20 m^Two / G, especially 2.5-12m^Two
/ G, and the magnetic powder having a Mohs hardness of 5 to 7
preferable. The magnetic powder is 10 to 7 relative to the weight of the magnetic toner.
Contains 0% by weight. When manufacturing the magnetic toner, the thermal toner is used.
With a heat kneader such as a le, kneader, or extruder
After kneading the constituent materials well, mechanical crushing and classification
Or the material is dispersed in the binder resin solution.
Then, obtain by spray drying, or binding
Emulsified suspension by mixing the specified materials with the monomers that make up the resin
Polymerization method Toner manufacturing
Each method such as the method can be applied. Photosensitivity when using the magnetic toner of the present invention
The surface hardness of the body is 8 g or more as measured by the following method,
The range of 10 to 100 g is preferable. Small hardness
If the photoconductor is easily scratched,
Disturbance of latent image and cleaning at high humidity
The magnetic toner that does not appear may appear. Also, the hardness is high
If it is too hard, remove the low resistance substance that forms on the surface of the photosensitive plate.
It becomes impossible, and the latent image is disturbed at high humidity. The above hardness is measured as follows. As an example, when measuring an OPC photoconductor
I will talk about it. The OPC photosensitive member is, for example, HEIDON14
Fixed to the sample stand of the mold surface texture measuring machine (made by Shinto Kagaku),
Needle made of diamond on the OPC photoconductor (conical shape and cone angle
It is 90 °. However, the tip is hemispherical with a diameter of 0.01 mm
Has become. ), Apply a vertical load xg, and
Move the table at a speed of 50 mm / min, and
Scratch the surface. The width of this scratch is measured, for example, by a micro hardness meter M.
Measure with a microscope attached to VK-F (manufactured by Akashi Seisakusho). In the above operation, the load xg is, for example, 10 g,
15g, 20g, 25g, 30g, 35g, 40g, ...
Repeatedly, the linear regression relationship between the scratch width and the load
Calculate the load that causes a 50μ scratch, and use the OPC exposure
The hardness of the body. If the OPC photoconductor is a drum,
Is an OPC feeling so that it is scratched in the axial direction of the drum.
It is necessary to set the light body on the sample. When the magnetic toner of the present invention is used,
The blade cleaning method and fan
-Brush cleaning method, magnetic brush cleaning method
Formulas and the like are used, but in the present invention, the toner of the present invention is used.
Considering the excellent combination with the
The decleaning method is preferable. Also a cleaner
Toner cleaning as needed just before reaching
A charge removing step or the like may be provided to facilitate this. Cleaning in Figures 1 and 2 of the accompanying drawings
An example of an apparatus is shown. In the drawings, 1 indicates a photoconductor, and this photoconductor is
It is adapted to be rotated in the direction indicated by the arrow in the figure.
During operation of the apparatus, an electrostatic latent image is formed on the photoconductor 1 by a known method.
Formed, the latent image is visualized by using toner
The developed image is transferred to a transfer material. Sensitive after transfer
In order to remove the toner 2 remaining on the body 1, a cleaner
A ringing device 7 is provided. The cleaning device shown in FIGS. 1 and 2 is
The surface of the photoconductor 1 so as to scrape off the toner 2 on the photoconductor 1.
The cleaning member 8 that is in contact with the
The toner detached from the photoconductor 1 is collected by the member 8.
The collecting member 9 is provided. Generally, the collecting member 9
It is placed so that it contacts the surface of the light
The toner scraped off by the sealing member 8 cleans the toner.
To prevent it from splashing out of the device. The cleaning member 8 is made of urethane rubber or the like.
An elastic rubber blade with JIS-A hardness of 60 ° to 80 ° is preferred.
It is preferable that the photoconductor 1 has a corner as shown in FIGS.
It is possible to make contact with each other at different degrees. Abut in this case
In the case of the pressure shown in Fig. 1, a linear pressure of 5 to 20 g / cm is preferable.
In the case of Fig. 2, the line pressure is 30-40g / cm.
Is preferred. [0058] [Embodiment] The basic constitution of the present invention is the feature
As described above, the present invention will be specifically described based on the following examples.
explain. However, this does not prevent the practice of the invention.
The embodiment is not limited in any way. Number of copies in the examples
Is parts by weight. (Example 1) Styrene-butyl methacrylate
-Dimethylaminoethyl methacrylate (weight ratio
7: 2.5: 0.5) 100 parts by weight of copolymer, BET ratio
Surface area 5m^Two Magnetite 4 with Mohs hardness of 5.5 / g
0 parts by weight, and a weight average molecular weight of 15,000 and a boiling point of n-
Hexane extracted 20% by weight polypropylene 3
Parts by weight are mixed and melt-kneaded in a roll mill at 160 ° C.
Was. After cooling, coarsely crush with a hammer mill, then jet powder
Finely pulverized with a crusher. Then classify using a wind classifier
The black fine powder with a volume average particle size of about 13 μm
Obtained as a magnetic toner. The friction of this unattached magnetic toner
The rubbing coefficient was 0.28. On the other hand, silica fine powder synthesized by the dry method
(Specific surface area approx. 130 m^Two / G) Stir 100 parts by weight
While having a silicone oil (25
Viscosity at ℃ 70cps, amine equivalent 830) 12
60 minutes by keeping the temperature at about 250 ° C.
For a while. Triboelectric charge of generated silica is +1
It was 30 μc / g. The hardness of this silica is Mohs hardness
It was 6.0. 100 parts by weight of the magnetic toner is attached to the above side chain.
Silica fine powder treated with silicone oil containing min
0.4 part by weight was externally added to obtain a magnetic toner. This magnet
The dynamic friction coefficient of the knack was 0.30. On the other hand, the Tg measured by DSC is 80.
Methyl methacrylate-styrene of 9 ° C or higher (weight ratio 9:
1) Laminated OPC having charge transport layer made of copolymer
The photosensitive drum is made on the conductive cylinder to obtain the photosensitive drum.
Was. The hardness of this photosensitive drum was 21 g. The obtained photosensitive drum and magnetic toner are commercially available.
It was applied to PC-10 (manufactured by Canon Inc.). At this time, the magnetic toner remaining on the drum
Was cleaned using an apparatus as shown in FIG.
In that case, the blade is urethane rubber with JIS-A hardness of 65 °.
And contact with the photosensitive drum at a linear pressure of 15 g / cm
I let it. Running test of 10,000 sheets under normal environment
However, a clear image with stable image density and no image distortion was
A gnar image was obtained. Furthermore, a running test of 10,000 sheets was performed.
After a while, the image density was stable and good without image distortion.
An image was obtained. The same experiment was performed at 30 ° C., 90% RH, 1
It was carried out in an environment of 5 ° C and 10% RH, but it was also good.
I got good results. The laminated OPC photosensitive drum after the test is new
It was in a clean state with no damage, almost like the product. (Comparative Example 1) Polypropylene used in Example 1
In the same manner as in Example 1 except that pyrene was not added, a magnetic toner not added externally
A ner was prepared. The dynamic friction coefficient of the magnetic toner without external addition is
It was 0.12. A running test was conducted under high temperature and high humidity.
However, a remarkable image disturbance occurred. Comparative Example 2 Weight average molecular weight 2800, boiling
Do not use 60% polyethylene extracted from n-hexane.
The same procedure as in Example 1 was carried out except that A running test was conducted under high temperature and high humidity.
However, a remarkable image disturbance occurred. The movement of this magnetic toner
The coefficient of friction was 0.14. (Comparative Example 3) Weight average molecular weight of 45,000,
Boiling point n-hexane Extraction content 3.0% polypropylene 8-fold
An experiment was conducted in the same manner as in Example 1 except that the amount part was used.
Was. The dynamic friction coefficient of the toner was 0.67. High temperature
In a running test under humidity, many scratches were generated on the photoconductor.
And the image was distorted. (Comparative Example 4) Silicon having an amine in the side chain
Magnet without silica powder treated with powder oil
Similar to Example 1 except using a polar toner
Then, an image drawing test was performed. Running test of 10,000 sheets under normal environment
The good image with stable image density and no image distortion
Was obtained, but after the running test was completed, a laminated OPC feeling was obtained.
When the light was taken out and the surface was observed, damage and film
Substantially no ringing was observed, but
The surface was slightly rough in comparison. [0074] The magnetic toner of the present invention has a proper polishing property.
A non-magnetic inorganic material that has been treated with silicone oil
Since it is externally added to the surface of the toner particles, cleaning
Excellent in environmental stability and durability of multiple sheets
Is what it is.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a cleaning device having a cleaning blade installed in the counter direction. FIG. 2 is an explanatory diagram of a cleaning device having a cleaning blade installed in a forward direction. [Explanation of reference numerals] 1 photoconductor 2 magnetic toner 8 cleaning blade

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Seiichi Takagi               3-30-2 Shimomaruko, Ota-ku, Tokyo               Non Corporation                (56) Reference JP-A-58-189649 (JP, A)

Claims (1)

(57) [Claims] A polyalkylene having a weight average molecular weight of 3,000 to 80,000 and a boiling point n-hexane extract content of 5 to 60% by weight is contained in an amount of 1 to 10 with respect to 100 parts by weight of the resin component.
1 part by weight and magnetic toner particles containing 10 to 70% by weight of magnetic powder (based on toner weight), and silica fine powder treated with silicone oil having amine in the side chain, A magnetic toner for developing an electrostatic charge image, which has a dynamic friction coefficient of 0.20 to 0.50. 2. The silica fine powder is dry silica fine powder.
The magnetic toner for developing an electrostatic charge image according to item 4. 3. The magnetic toner for developing an electrostatic charge image according to claim 1, wherein the fine silica powder is contained in an amount of 0.01 to 20% by weight (based on the magnetic toner). 4. The magnetic toner for developing an electrostatic charge image according to claim 3, wherein the fine silica powder is contained in an amount of 0.1 to 3% by weight (based on the magnetic toner). 5. Polyalkylene has a boiling point of n-hexane of 10 to 10 parts.
The magnetic toner for developing an electrostatic image according to any one of claims 1 to 4, containing 45% by weight. 6. Polyalkylene has a weight average molecular weight of 5,000 to 60.
6. The magnetic toner for developing an electrostatic charge image according to any one of claims 1 to 5, having 000.