JPS60117260A - Magnetic particle for toner coating and toner coating method - Google Patents

Abstract

PURPOSE:To coat the surface of a developer carrier with magnetic particles in an uniform and thin layer and to attain sufficient frictional charging by having toner with a magnetic coating film and frictional charging property. CONSTITUTION:Magnetic particles 5 in a container 3 form a magnetic brush 8 with a magnetic field produced between the S pole of a magnet 7 and a magnetic blade 6. Then, the magnetic particles and toner are stirred and mixed by the rotation of a sleeve 2 while the magnetic brush 8 is maintained. The mixture of the toner and nonmagnetic particles is inhibited by a blade from moving and elevated at the side of the magnetic blade 6 of the container 3 to enter circulating motion. Consequently, the toner is charged frictionally by the stirring and mixing of the magnetic particles. The charged toner is applied over the surface of the sleeve 2 uniformly and thinnly by the magnetic brush 8 formed near the magnetic blade 6 with influencing force.

Description

[Detailed Description of the Invention] The present invention utilizes a non-magnetic developer (hereinafter referred to as toner).
Regarding developing devices for developing electrostatic latent images, various Maki devices have been proposed and put into practical use as dry component developing devices. However, it is extremely difficult to form a thin layer of dry-component developer in any developing device;
Only relatively thick layers could be formed. However, now that improvements are being made in the clarity and resolution of developed images,
It is essential to develop an apparatus capable of forming a thin layer of dry-component developers.

Regarding the formation of a thin layer of a dry-component developer, Japanese Patent Application Laid-Open No. 1983
-43037 has been proposed and has been put into practical use. However, this concerned the formation of a thin layer of magnetic developer. Magnetic developers must have a magnetic material added to them in order to have magnetism. There are problems such as poor color quality during color 111 rendering due to the fact that the

For this reason, there are methods for forming a thin layer of toner, such as using a cylindrical brush made of soft bristles like beaver hair and applying the toner all over the brush, or creating a thin layer of toner with a cylindrical brush made of soft bristles such as beaver's hair, or using a cylindrical brush with soft bristles such as beaver hair, and applying the toner completely on the brush. A method has been proposed in which the toner is applied using a doctor blade, etc. to the upper mouth.
Although it is an iJ function, it is not applied uniformly, and only by rubbing the fiber brush of the developing roller soil, the brush #lII wholesale 1
Since no triboelectric charge is imparted to the toner present in between, there is a problem in that ghosts and the like are likely to occur3.Furthermore, since toner is used, it is difficult to prevent toner from leaking from the device. Ta. Furthermore, there is a drawback that the toner is easily subjected to a load and is fused to the developing roller.

The present invention eliminates the above-mentioned conventional problems, applies toner as a uniform thin J- to the curve of the developer conveying member (developing roller, etc.), and has a sufficient friction band 7M, ? 1: The purpose is to enable effective toner application.

Furthermore, it is an object of the present invention to completely prevent the toner from spilling out of the developing device, and furthermore, it is aimed at completely preventing the toner from spilling out from the developing device, and further, by setting 11≠load to the toner, all problems occur. The aim is not to.

In order to achieve the above object, the toner application method according to the present invention includes a developer container for storing toner and magnetic particles for toner application; 6. A toner carrier for conveying the toner to the image carrier, and a mechanism for forming an air jib by toner application magnetic particles that come into contact with the toner carrier on the upstream side of the toner outlet 1-1 of the MfJ developer container. C) A toner head coating method in which a thin layer of toner is formed on a toner carrier by a magnet that waits for the toner, and the magnetic particles for toner dispersion are coated with a magnetic film. This is a toner distribution method characterized by friction and friction (4).Furthermore, the magnetic particles for toner application method according to the present invention are used for storing toner and magnetic particles for toner application. a toner carrier, a toner carrier that conveys the toner to the latent image carrier, and a toner coating member that contacts the toner carrier on the upstream side of the toner outlet of the developer container; magnetic particles for toner application used in a toner application method in which a magnet forming a magnetic brush is arranged and a thin layer of toner is formed on a toner carrier. The toner coating material is coated with a JiB film and has a friction zone with the toner, and is characterized in that it is coated with a JiB film and has a friction zone with the toner.

According to the present invention, regarding development,
-It doesn't look like it is shown in No. 43037 - Ingredient 4
・.

Take advantage of the advantages of pumping development! ': Runot, j, Moraronno, toner is a developer carrier'-e Koki 71. It can be applied as desired.

Furthermore, according to the present invention, it is possible to avoid the fact that physical properties such as adhesion and releasability of toner and magnetic particles, friction zone r [lower 1'' and fluidity of toner] greatly affect coating and development. In order to achieve this, the physical properties of the developer are adjusted by using, as magnetic particles, Koya-en-O-Q particles whose surface only has a friction band 11'1.1'l of polarity opposite to that of the toner, and which is coated with a magnetic film.
It becomes possible to achieve a good coating state.

In particular, the greatest feature of the present invention is that the load on the toner is light (the force exerted by the magnetic particles on the toner particles is small). In other words, to clarify this point, in recent years pressure fixing methods have been increasingly adopted for fixing due to demands for energy saving and immediacy, but in order to minimize paper wrinkles, curls, and gloss, It is desired that it be lowered.

For this reason, it is necessary to use materials with low mechanical strength for toner, or toner made using such materials tends to undergo a fusion phenomenon in the developing machine, making it difficult to withstand use. It is something that will disappear.

However, if the specific gravity of the magnetic particles present with the toner is large, the above phenomenon will be accelerated.
In other words, in the present invention, this requirement can be achieved by using eaves particles with a small specific gravity, the surface of which is covered with a magnetic film, as magnetic particles. be.

In the present invention, the latent image carrier to be developed may be a drum-shaped or belt-shaped member having an entire photoreceptor or insulating layer. Further, the magnetic poles are provided by adhering a plurality of magnet rolls or bar-shaped magnets magnetized with magnetic poles of the same polarity or different polarity in the axial direction to the fixed support portion. In addition, as a rotating developer carrier, aluminum, copper, stainless steel,
It is possible to use a sleeve made of non-magnetic metal such as brass or a synthetic resin material, or an endless belt made of resin or metal, whose peripheral surface improves toner transportability and charging characteristics. If necessary, the surface may be roughened or a gold film with an uneven pattern may be applied.

Further, as the regulating member, a blade plate or a wall made of a magnetic material such as iron or a non-magnetic material such as aluminum, aluminum, resin, etc. is used.

Hereinafter, the entire history of the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows a sectional view for explaining the coating principle of the present invention.

In the figure, reference numeral 1 denotes an electrophotographic photosensitive drum, which holds a latent image formed by a latent image forming means (not shown), and rotates in the direction of arrow a to pass through a developing position shown in the drawing. A non-magnetic sleeve 2, which is a developer carrying member that carries toner, faces the photosensitive drum 1 with a predetermined gap therebetween, and this sleeve 2 rotates in the direction of the arrow. . A container 3 made of a non-magnetic material such as resin or aluminum is located above the sleeve 2 and stores a mixture of toner 4, which will be described in detail later, and magnetic particles 5, which will be described in detail later. A magnetic blade 6 is screwed as a regulating member downstream in the rotational direction of the sleeve. - On the other hand, on the opposite side of the sleeve 2 to the magnetic blade 6, a magnet 7 is fixedly placed.The mounting position of this magnet is determined by the relationship between the position of the magnetic pole and the magnetic blade 6; By locating the magnetic pole slightly upstream of the magnetic blade 6, the effect of the generated magnetic field provides even better results in terms of preventing the magnetic particles from flowing out and uniformly applying the toner.

In the above configuration, the magnetic particles 5 in the container 3 form a magnetic brush 8 due to the magnetic field generated between the S pole of the magnet 7 and the magnetic 7' blade 6. Then, as the sleeve 2 rotates, the magnetic particles, toner, and QJ are stirred and mixed while the old abrasive brush 8 is maintained. In this state, on the magnetic blade 6 side of the container 3, due to the presence of this blade 6, the mixture of toner and non-magnetic powder is
The vertical movement is prevented, and it rises and circulates in the direction of arrow C.

As a result, the toner is triboelectrically charged by the magnetic particles of the sleeve 2 or 4a by stirring and mixing with the magnetic particles. The magnetic brush 8 formed near the magnetic blade 6 applies the banded toner uniformly and thinly to the surface of the sleeve 2 by the mirror image force, and the toner is applied to the photoreceptor by 1°. to the opposite position.

On the other hand, the magnetic particles 5 constituting the magnetic brush 8 are attached to the magnet 7
By setting the binding force acting on it due to the magnetic field to be larger than the conveying force acting on it due to frictional force, the sleeve does not flow out toward the photosensitive drum as the sleeve 20 rotates. If there is toner within the area of the magnetic brush 8, the ratio of the magnetic particles of the magnetic brush 8 to the toner remains constant due to the rotation of the sleeve 2.
As a result, even if the toner on the sleeve is consumed during development,
The area of the magnetic brush 8 is automatically supplied with toner.

Therefore, it is possible to always supply and apply a constant amount of dove to the sleeve 2'2.

In the above explanation of the principle, a magnetic field is used as the regulating member, but a non-magnetic grade or a wall made of a non-magnetic material such as resin or aluminum constituting the Y-type device can also be used as the regulating member. However, in this case, the magnetic Jy
In order to prevent the outflow of one child, the gap 'f between the sleeve and the regulating member needs to be made even smaller than when using a magnetic field.

In addition, using a magnetic blade is more convenient in that a magnetic brush can be stably formed at the toner exit part by the magnetic field between the blade and the magnetic pole. Since the agent is a non-magnetic toner, container 3
There may be a problem that leakage is likely to occur from the area d on the side where the sleeve 2 is inserted. In order to prevent such leakage of toner from the region d, a magnetic brush may be formed between the sleeve and the container in the region d on the side where the sleeve enters the container.

In the present invention, as the magnetic particles described above, particles are used in which the core is non-magnetic and lightweight, and only the surface of the core is covered with a full ffi film. This magnetic particle is
For example, particles with a particle size of 5-100 μm are formed into a perfect spherical shape, and the core is made of Al powder, Al2O3 powder, 1 gaseous powder, TlO
The main ingredients are 2 powder, mica powder, and Tani's resin a-dera, and 0.1 to 10 μI'll of Ni is applied to the surface.

It can be coated with a magnetic film of C01Fe, ferrite, etc. In order to form it on the next surface of the JIA metal core, if the core is an electrically insulating powder. Electroless plating (also known as chemical plating)
Applying, the core is Hiro @ 'I! In the case of L powder, many conventionally known plating methods such as conventional plating may be applied. In the case of electroless plating, it goes without saying that the core material (ll-activation treatment) must be performed in advance before plating.

The lightweight particles, which are covered with a magnetic film only on their second side, are triboelectrically charged with a polarity opposite to that of the toner. The polarity between the toner and the lightweight particles whose surfaces are covered only with a magnetic film can be determined by a blow-off method using iron powder as a reference.

Furthermore, as the binder resin for the non-magnetic developer used in the present invention, 7j? Homopolymers of styrene and its substituted products such as listyrene, poly-P-chlorostyrene, and polyvinyltoluene; styrene-P-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers,
MF coalescence, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methacrylate Acid methyl copolymer, styrene-ethyl methacrylate copolymer, styrene-7-butyl tacrylate copolymer, styrene-acrylic-aminoacrylic copolymer, styrene-aminoacrylic copolymer, styrene-αchlor Methyl methacrylate copolymer, styrene
Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinylethyl niemil copolymer, styrene-vinyl methyl ketone co-J1ζ copolymer, styrene-butadiene copolymer, styrene-isozolene copolymer, Styrene-acrylo=1. Liluindene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer j1 [Styrenic copolymer such as coalescence; polymethyl methacrylate, 7]? Butyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, eyes? Lysol-copylene, polyester 1. J?
Riurethane, n”? Riamide, engineering, Jf xy resin, I ribinyl butyral, 71? Reacrylic acid resin, rosin,
Modified rosin, chiru-ξn411 fat, pht-nol resin,
Aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, rough-in waxes, etc. can be used alone or in combination for IIJu.

Any suitable pigment or dye can be used as a layer colorant in the toner used in the present invention.

For example, car? These are well-known dyes and pigments such as umburasoku, iron black, phthalocyanine blue, ultramarine, quinacridone, and benzidine yellow.

In addition, as charge control agents, amine compounds, quaternary ammonium compounds, organic dyes, especially basic dyes and their salts, penzyldimethyl-hexadecyl ammonium chloride, decyl-trimethylammonium chloride, nigrosine base, nigrosine hydrochloride, safranin γ
Also, crystal violet, metal-containing dyes, salicylic acid metal-containing compounds, etc. may be added.

The above toner structure may be used in a toner produced by a commonly used mixing-pulverization method, or may be used as a wall material or a core material, or both, of a microcapsule toner.

Examples are shown below, but the present invention is not restricted thereto in any way.

[Example 1] An example of the present invention will be explained with reference to FIG. In the figure, the same parts as in FIG. 1 are given the same reference numerals.

In this embodiment, the photoreceptor drum 1 is moved 60 cm in the direction of arrow a.
Rotates at a circumferential speed of /sec. 2 is 66va/in the direction of the arrow
Sleeve made of stainless steel (5 LIS 3 (+ 4) II) with an outer diameter of 32 mm and a thickness of 0.8 that rotates at a circumferential speed of 1 second.
The roughness of the circumferential surface was made 0.8μm (Rz) by using amorphous sandblasting.Meanwhile, inside the rotating sleeve 2, a fly light sintered type magnet 7ck was used.
The N pole of the first magnetic pole is set at a stationary position (2), and the N pole of the first magnetic pole is set at an angle of 30 degrees (θ in the figure) from the line connecting the center 0 of the sleeve 2 and the tip of the blade with respect to the magnetic blade 6. 3,
One of the second magnetic poles, S pole, is opposite to the iron piece 10, which is a magnetic 7515 installed on the sleeve person [1 side of the container].
i #, -) 5, the magnetic flux density on the sleeve surface of this 24th d★ pole is 1 current e', its peak value is 650 Gauss Rari in the presence of 10 of the iron piece, and the iron plate is 10'ff, removed. The condition is 400 yen. At this time, the second magnetic pole and iron piece 1
0, the #At angle of the iron piece 10 in the direction of rotation of the sleeve was set to 0.5 mm, and the distance f'j between the sleeve 2 and the iron piece 10 was set to 1.0 + im.

The magnetic blade 6 is made of iron and has a nickel plated surface to give a smooth surface. This blade 6 IJ
, the distance from the surface of the sleeve 2 was set to 200 μm.

The magnetic particles 5 are spherical An20. with an average particle size of 30μ. Negatively chargeable silica fine powder (Nihon Aerosil Co., Ltd. fiR-9
72) One layer of fif'f'JI' was externally added to 3H using a 7-shell mixer, and 1.0 (1,9) of it was extracted and used.

On the other hand, as toner 4, i: , +! , 3 parts of copper phthalocyanine pigment and 5 parts of negative charge control agent (alkyl salcylic acid metal chain) were added to 100 parts of realester resin, and charged to negative (-) polarity with an average particle size of 12 μrn. 200g of cyan powder was prepared. Then, the toner and magnetic particles were mixed well and placed in a container 3. The mixture of toner and magnetic particles in the container 3 can be observed when the amount of toner is low, especially when the toner particles are transported by the sleeve under the magnetic field. It's a sacrifice.

In the developing device having the above configuration, as the sleeve rotated, a thin layer of only toner having a thickness of about 100 μm was formed on the surface rfu of the sleeve 2. When this toner layer was measured by blow-off method, it was found that (i) 'il,' was uniformly measured at a potential of -6 μc/g.
I confirmed that L.

On the surface of the photosensitive drum 1 facing the sleeve 2, there is a dark area +6 (1314 parts + 150 parts at 10V) as an electrostatic image.
Form a charge pattern of V, and set the distance from the sleeve surface to 300
It was set to μm. Zoshi-C1 For the above sleeve, power supply E is applied to 9 frequency 800 Flz, peak-to-peak value is 1
．． When applying a voltage of 4 kV and a center value of 1-3 (10 V), a high-quality developed image was obtained with no uneven development, no overprinted images, and no fogging. I was able to do that.

Also, when the mixture in the container 3 is 19J, the magnetic 'J:i' is not completely consumed and only the toner is vj.
, consumed by the statue. Further, the developing function remained unchanged until the toner was almost completely consumed.

After consuming the above toner, the current 14! When I took out the device ft and looked at the bottom of the sleeve 2, I found that there was not only magnetic particles but also toner leakage.

The number of magnetic poles provided inside the sleeve is 2, the first and second magnetic poles.
There is no need to limit it to. The magnetic brush formed by the second magnetic pole is not limited to the installation of the magnetic member 10, and a wall may also be used.

In this case, the presence of the magnetic part is no longer necessary, and the S pole arrangement Mff: shown by the chain line in FIG. 2 is adopted. Also, the container is 4+
'If it is an FA material, it is possible to form magnetic grade 6 and iron piece 10 shown in Fig. 2 on the wall of the container.
This piece of iron can replace a portion of the container with an axially convex portion of the sleeve.

In the above, the case where the S pole is used as the second magnetic pole has been exemplified, but of course the N pole may also be used. Sorry, the blade plate 6 made of a magnetic material is shown as an example of the regulating means, but a wall or a plate-shaped part I made of a non-magnetic material such as synthetic resin, aluminum, brass, or stainless steel may also be used. When using a magnetic material, unlike when using a Ti magnetic material, a 4a field is not generated between it and the first magnetic pole, so the type of brush created by the magnetic particles inside the container is different, and the magnetic particles move downstream of the container. However, in this regard, i9 can be determined by setting the gap between the sleeve and the non-magnetic material regulating means to about half or less of the particle diameter. Regarding f): In addition to attaching this separately from the container, it may also be used as a regulating plate at -t'111' of the container. And furthermore:! JJ, i′! ! The bias at the time is not limited to an alternating voltage, and a voltage bias is also effective.

[Example 2] Fine silica powder Aeronol 200 (r+ manufactured by Aeronol) was placed in a closed Henschel mixer heated to 70°C, and when the silane coupling agent was 10% to the silica, t! 17. at high speed while dropping γ-aminonoropyltriethoxysilane diluted with alcohol so as to obtain 17. Stirred. The obtained fine powder is 1
At 20° C., after drying, round it in a Henschel mixer; JL, 49j, and mix the silica with dimethyltsuk IJ Lucisin at 10 oki, 1); -%. It was sprayed.?Itρ1.
The mixer was then opened to atmospheric pressure. This mixture was dried at low speed at atmospheric pressure at 60° C. for 5 hours to obtain positively chargeable silica fine powder. One part by weight of this fine silica powder was added to Al powder with an average particle size of 50μ and Ni was added to a thickness of 0.5μ.
It was added externally to 100 parts by weight and 117 parts of straight particles plated on a Henschel mixer, and 100 gk was taken out.

On the other hand, as the toner 4, styrene-acrylic resin 1
5 parts of a rhodamine-based M material and 2 parts of a positive charge control agent (grossin-based) were added to 0.00 m2 to prepare 150 g of positively chargeable powder with an average particle size of 10 μm.

Also, the dark area -600 as a static full image on the surface of the photoreceptor drum.
v, forming a charge pattern of -200v in the bright area, frequency 1000Hz, peak-to-peak value 1.3k for the sleeve
When the same procedure as in Example 1 was performed except that a voltage of -:300 V was applied to the center value, a voltage of +8 V was applied on the sleeve.
The toner charged to μc/lI was uniformly applied, and a good image was obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view for explaining the principle of the developing device of the present invention. FIG. 2 is an embodiment of the present invention.
Diagram 0 161. Photosensitive drum, 2...Currently 1 house ill Jj
Sleeve with two sleeves, 3.1. container, 4
9.・Tozu, 5...4 viscera, 1 raw puss, 6...Required as a regulating member a) Sea 1゛, 7°゛4+lithium ・10...13 J' which is a magnetic ablation 7゜1゛ ′−
Bank 11'l I+- line: ゛Fig. 1

Claims (2)

[Claims] (1) A developer container that stores toner and 411i particles for toner application, a toner carrier that conveys the toner to the latent image carrier, and an upstream side of the toner outlet of the developer container.
A toner coating method comprising forming a thin layer of toner on the toner carrier by arranging a magnet with a magnetic pole to form a magnetic brush made of magnetic particles for applying toner that are in contact with the toner carrier. This is a patented toner application method in which the magnetic particles for toner application are covered with a magnetic film and have frictional electrification with the toner. (2) A developer container that stores toner and magnetic particles for toner application, a toner carrier that conveys the toner to the latent image carrier, and a toner carrier that contacts the toner support member on the upstream side of the toner outlet of the developer container. Toner coating magnetic particles used in a toner coating method for forming a thin layer of toner on the toner carrier by disposing a magnet forming a magnetic brush made of toner coating magnetic particles, the particles being coated with a magnetic film. Magnetic particles for toner coating, characterized in that they have frictional (j'7) electrical properties with the toner.