JPH02887A - Magnetic recording method and magnetic recording toner used for same - Google Patents

Abstract

PURPOSE:To obtain a sharp visible image with superior transparency by performing development by using magnetic particles having magnetism on a magnetic latent image and image particles which are attracted electrostatically to the magnetic particles and then transferring only the image particles to a body to be transferred. CONSTITUTION:The development is carried out by using the magnetic particles having the magnetism on the magnetic latent image and the image particles which are attracted to the magnetic particles and only the image particles are transferred to the body to be transferred. Namely, the magnetic latent image is formed by performing recording on the surface of a magnetic body 1 with magnetic moment parallel to the surface and the magnetic particles 2 are fixed on the magnetic latent image with the force of the magnetism of the image part of the magnetic latent image. Then the magnetic particles 2 and image particles 2 attract each other electrostatically because charges are held on the particle surfaces and opposite in polarity. Thus, the magnetic particles 2 and image particles 3 attract each other electrostatically and toner for magnetic recording formed of a hetero-condensed body is used to improve the dispersibility and flowability of the magnetic recording toner; and the magnetic latent image is developed uniformly and the stable and sharp visible image is obtained.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a magnetic recording method and a magnetic recording toner,
In particular, the present invention relates to a magnetic recording method capable of obtaining clear color images and a magnetic recording toner used therein.

<Prior Art> As a conventionally proposed magnetic recording method capable of obtaining a color image, there is a method of developing with a magnetic toner consisting of a colored pigment and magnetic particles. Or II! EE TR
ANSACTIONS ON MAGN [! TlC5,
10, 1, 60 (1974), by changing the size of colored magnetic particles depending on the type of color,
There is a method of forming a magnetic latent image that matches the size of magnetic particles of each color to obtain a color image. Also, IEEE
RANSACTIONS ON MAGNETIC3,
1B, 6,1262. (1982), there is a method of obtaining a multicolor image by varying the magnetic strength of a magnetic latent image.

<Problems to be Solved by the Invention> However, in either method, the image obtained is composed of magnetic particles and colored pigments, and the magnetic material constituting the magnetic particles has a black or dark brown color. Therefore, the image obtained is due to the black or dark brown color of the magnetic material.
The image becomes dull in tone or lacks transparency, making it impossible to obtain a clear color image.

Further, even when an image produced by the above method is used as a transmission image, it cannot be used as a transmission image because the black or dark brown magnetic particles prevent the transmission of light as described above.

Means for Solving the Problems> The present invention has been made in view of the above-mentioned current situation, and specifically, a magnetic latent image consisting of a magnetized image area and an unmagnetized background area on a magnetic material. In the magnetic recording method, a visible image is obtained by developing, transferring and fixing onto a transfer object, and developing the latent image using magnetic particles having magnetism and image particles electrostatically attracted to the magnetic particles. , is a magnetic recording method characterized in that a visible image is obtained by transferring only image particles to a transfer target.

In particular, in the above magnetic recording method, a stable and clear visible image is obtained by using a magnetic recording toner consisting of magnetic particles having magnetism and image particles electrostatically attracted to the magnetic particles.

<Detailed description and operation of the invention> Using drawings showing an embodiment of the magnetic recording method of the present invention,
This will be explained in detail below. FIG. 2 is a diagram showing a magnetic latent image. A magnetic latent image is formed by recording with a magnetic moment parallel to the surface of a magnetic material (+) (FIG. 1 shows the direction of the magnetic moment of the image due to magnetization). In addition to being formed by the method described above, the magnetic latent image is recorded using a magnetic moment perpendicular to the surface of the magnetic material.
A known technique such as a so-called perpendicular magnetization method can be used.

The magnetic material (1) is a material in which a magnetic layer of magnetite, cobalt, nickel, or an alloy containing these is provided on a non-magnetic metal or plastic substrate by vacuum deposition, electrolytic plating, or electroless plating, or a material such as ferrite. Known materials such as those obtained by coating magnetic powder on the above-mentioned base material using a resin binder can be used. Further, on the magnetic layer configured as described above,
, a thin layer of inorganic material such as AlNZnS, or a thin layer of inorganic material such as polyethylene, polytetrafluoroethylene, polyurethane,
The magnetic layer can be protected by providing a thin layer of a commonly used organic material such as acrylic resin or polyamide resin.

FIG. 3 shows magnetic particles (2) on a magnetic latent image according to the present invention.
FIG. 3 is an explanatory diagram showing development with a toner consisting of image particles (3) electrostatically attracted to magnetic particles (2). The magnetic particles (2) are fixed on the magnetic latent image by the magnetic force of the image area of the magnetic latent image.

The magnetic particles (2) and the image particles (3) are electrostatically attracted to each other because charges are held on the particle surfaces and their polarities are opposite.

The magnetic particles (2) are mainly composed of generally known magnetic powders such as iron oxide, triiron tetroxide, barium ferrite, and manganese-zinc alloy rings, and resin. Here, it is preferable that the resin has an electrical resistance capable of retaining a charged charge, has uniform and stable charging properties, is not sticky, and does not deteriorate or change in quality over a long period of time. Specifically, Polystyrene-acrylic acid copolymer, polyolefin, Beau J ester, polyurethane, and resins modified by introducing various polar groups into these resins are used, but the invention is not limited to these resins (various resins can be used). .

Magnetic particles (2) are obtained by kneading the above-mentioned magnetic powder and the above-mentioned resin and then granulating them, or by coating the surface of the above-mentioned magnetic powder with the above-mentioned resin. Here, the azo synthetic dye that controls the polarity and amount of charge in the resin described above,
By adding generally known charge control agents such as fatty acid metal salts and quaternary ammonium salts, magnetic particles (2) with stable surface charges can be obtained.

The image particles (3) are mainly composed of pigments, dyes, and fats. Here, the resin has good adhesion to the transferred object, can uniformly and stably maintain a charge opposite to the surface charge of the magnetic particles (2) configured as described above, and does not deteriorate or change in quality over a long period of time. Preferably, polystyrene-acrylic acid copolymers, polyolefins, polyesters, polyurethanes, and resins modified by introducing various polar groups into these resins are used. Image particles (3) are obtained by granulating the above-mentioned pigment and dye after the above-mentioned kneading.
get.

Even more preferably, by coating the surface of the image particles (3) with the various resins described above, the image particles (3) can be
It is possible to improve the charge characteristics of the surface and the fixability to the transferred object.

Furthermore, various kinds of pigments and dyes are used depending on the visible image to be obtained.

As a method for developing a toner consisting of magnetic particles (2) and image particles (3) onto a magnetic latent image, magnetic particles (2) and image particles (3) are mixed and stirred in advance to attract each other electrostatically, and then A method of developing by conveying the magnetic particles (2) onto the magnetic latent image, or a method of conveying the magnetic particles (2) onto the magnetic latent image, fixing the magnetic particles (2) on the image area by magnetic force, and then developing the charged image particles ( 3) may be developed by fixing it to the magnetic particles using electrostatic force.

In particular, as shown in Figure 4, magnetic particles (2) and image particles (
3) By using a magnetic recording toner that is electrostatically attracted to form a heteroaggregate, the dispersion and fluidity of the magnetic recording toner are improved, and the magnetic latent image can be developed uniformly and stably. Obtain a clear visible image.

Further, the magnetic particles (2) and the image particles (3) can be prepared by either a dry method in which they are used as powder, or a wet method in which they are dispersed in an insulating solvent such as a hydrocarbon solvent. In particular, the above-mentioned wet method can handle image particles of 1 pn or less, and can obtain high-definition images.

The magnetic particles (2) having magnetism configured as described above and the image particles (2) electrostatically attracted to the magnetic particles (2).
In the magnetic latent image developed in step 3), only the image particles (3) are transferred to the transfer object (4) to obtain a visible image, as shown in FIG. After the image particles are transferred, heating or thickening is performed to obtain a visible image in which the transferred object (5) and the image particles (3) are firmly adhered.

When transferring the image particles (3) onto the transfer target (4), the image particles (3) are transferred to the transfer target by overlapping the developed magnetic latent image and the transfer target (4), The magnetic particles (2) are fixed on the magnetic material (1) by the magnetism of the ferromagnetic material and are not transferred to the transferred object (4). Here, if the transferred object (4) is conductive, the magnetic particles The charges on the surfaces of the magnetic particles (2) and the image particles (3) escape through the transfer object, and the electrostatic force that was working between the magnetic particles (2) and the image particles (3) disappears, so the image particles (3) can be efficiently transferred.

Furthermore, an electric field having the opposite polarity to the surface charge of the image particles (3) and the same polarity as the surface charge of the magnetic particles (2) is applied to the transfer object (4), or the transfer object (4) is By charging the surface charge of (3) with the opposite polarity and the same polarity as the magnetic particles (2), the transferred object (4) and the image particles (3) can be efficiently transferred to the transferred object (4) by electrostatic force. transferred, and the magnetic particles (2) are electrostatically repulsive and ferromagnetic (+)
It is fixed on the magnetic material (1) by the magnetism of the material to be transferred (
4) is not transferred.

Various other modifications are possible within the range of design changes.

<Example> The present invention will be explained in detail below with reference to Examples.

<Example 1> The magnetic material was an aluminum cylinder electrolessly plated with cobalt, and an I1 layer of polytetrafluoroethylene with a thickness of about 0.1 μm was provided on the plated surface.

A color image was separated into yellow, magenta, and cyan using a magnetic head on the magnetic body constructed as described above, and a yellow image was recorded to obtain a magnetic latent image.

The magnetic particles are made of magnetic powder made of triiron tetroxide with an average particle size of 0.3 μm, mixed with ethyl maleate acrylate.
It is made by adding aliphatic metal soap to a resin made of styrene copolymer, kneading it, and then crushing it, and the average particle size is about 10.
Magnetic particles of μm were obtained.

Image particles are yellow pigment (benzidine yellow YT564)
A resin made of chlorinated polypropylene is kneaded and granulated to give an average particle size of 8 μm, and the surfaces of the resulting particles are coated with nitrocellulose to give an average particle size of 9 μm.
m cost image particles were obtained.

After kneading the magnetic particles and image particles configured as described above,
It was triboelectrified by stirring and then developed by contacting it with the magnetic latent image constructed as described above.

The magnetic latent image developed as described above was brought into contact with a coated paper to which an electric field was applied from the back side, so that only the image particles were transferred, and then the image was fixed by being passed between hot rolls.

Furthermore, magnetic particles similar to those described above and a yellow pigment were added to the magenta and cyan magnetic latent images that recorded magenta and cyan images in the same manner as described above. Cyan pigment (
In the same manner as described above, magenta and cyan image particles were sequentially transferred and fixed onto coated paper which had been transferred and fixed with yellow image particles to obtain a color visible image.

<Example 2> A magnetic material was created by applying and drying a coating liquid in which CrO□ powder and a polyimide binder resin were dissolved and dispersed on a base material made of a polyimide film (thickness: 100 μm). A red original mask for a color filter was placed on the magnetic material configured as described above, and a red magnetic latent image was obtained by flash exposure.

The magnetic particles had an average particle size of 0.25 μm and the surface of the ferrite was coated with polystyrene and polyisoprene rubber.

The image particles are made by kneading alkyd resin and red dye (Brilliant Scarlet 3R) and then mixing them with aliphatic hydrocarbon (solvent).
The particles were dispersed and granulated in Isopar H (trade name, manufactured by Esso, USA) to obtain image particles having an average particle diameter of 0.5 μm.

The magnetic particles constructed as described above were dispersed in an aliphatic hydrocarbon (trade name: Isopar H, manufactured by Esso, USA), and brought into contact with the above-mentioned magnetic material to fix the magnetic particles in a magnetic latent image.

Furthermore, the image particles dispersed in the aliphatic hydrocarbon were positively charged by stirring in the aliphatic hydrocarbon, and then developed by bringing them into contact with the magnetic particles fixed on the above-described magnetic latent image. The developed magnetic latent image on the above-mentioned keyaki was transferred by contacting it with a transfer paper made of negatively charged polyester, and then fixed with thermoplastic.

Furthermore, magnetic particles similar to those described above are fixed to a magnetic material having a yellow magnetic latent image and a blue magnetic latent image in the same manner as described above, and then the red dye is converted into a yellow dye (cation yellow) and a blue dye (methylene blue). Same as above except for using the same yellow image particles and blue image particles,
A color filter was obtained by sequentially transferring the red image particles onto a transfer paper made of polyester.

<Example 3> A color image was separated into yellow, magenta, and cyan using a magnetic head on a magnetic body constructed in the same manner as in Example 1, and a yellow image was recorded to obtain a cost magnetic layer image. The magnetic particles of the magnetic recording toner are prepared by dispersing magnetic powder of nickel zinc ferrite (manufactured by Sumitomo Cement ■) with a particle size of 0.01 to 0.03 μm in a monomer of diethylaminoethyl methacrylate-styrene. 2′-Azobis(2-amidinopropane) hydrochloride is called an initiator.
By soap-free polymerization, the average particle size is 0.59μ
m magnetic particles were obtained.

Image particles are yellow pigment (benzidine yellow YT564)
After kneading and dispersing in a 7-mer consisting of hydroxyethyl methacrylate-ethyl styrene diacrylate-acrylic acid, adding sodium P-styrene sulfonate and carrying out soap-free polymerization using potassium persulfate as an initiator, Cost image particles with an average particle size of 0.124 μm were obtained.

By mixing the magnetic particles and image particles configured as described above in an aqueous solution of pH 5, a magnetic recording toner consisting of a heteroaggregate in which the image particles are coated on the outside of the n-type particles by electrostatic attraction is produced. After that, the phenomenon occurred by bringing the magnetic recording toner constructed as described above into contact with the magnetic layer image constructed as described above.The magnetic tidal image developed as described above was produced by applying an electric field from the back side Only the yellow image particles were transferred by contact with synthetic paper, and then fixed by passing between heated rolls.

Furthermore, magnetic particles similar to those described above, a yellow pigment, a magenta pigment (Watch Lang Red RT761D) and a cyan pigment were added to a magenta magnetic latent image and a cyan 1N magnetic latent image in which magenta and cyan images were recorded in the same manner as described above. (Phthalocyanine Blue) was used to sequentially transfer and fix magenta and cyan image particles to a coated paper on which yellow image particles had been transferred and fixed in the same manner as described above to obtain a color visible image.

The color visible images obtained on the above-mentioned birch had a quality equivalent to that of offset printing, and there was very little variation in image quality even when 100 sheets were printed.

<Effects of the Invention> The present invention is as described above, and according to the present invention, magnetic particles are developed on a magnetic latent image, and image particles electrostatically attracted to the magnetic particles are used to develop the image particles. Magnetic recording is capable of obtaining transparent and clear visible images without transferring black or blackish-brown magnetic particles, since only the magnetic particles are transferred to the transferred material and a visible image is obtained. It is a method of extremely great industrial value.

In particular, by using a magnetic recording toner in which magnetic particles and image particles are electrostatically attracted to each other, the dispersion and fluidity of the magnetic recording toner are improved, and the magnetic latent image can be developed uniformly and stably. And a clear visible image can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an embodiment of the magnetic recording method of the present invention, FIG. 2 is a plan view showing a magnetic latent image, and FIG. 3 is an image of the magnetic latent image of the magnetic recording method of the present invention. FIG. 4 is an explanatory diagram showing an example of the magnetic recording toner used in the present invention. (1) Magnetic material (4) Transferred object (2) Magnetic particles (3) Image particles Figure 1 Figure 2 Figure 3 Gray

Claims (1)

[Scope of Claims] (1) A magnetic latent image consisting of a magnetized image area and a non-magnetized background area is developed on a magnetic material, and is transferred and fixed to a transferred object to obtain a visible image. In the recording method, the magnetic latent image is developed using magnetic particles having magnetism and image particles electrostatically attracted to the magnetic particles, and then only the image particles are transferred to the transferred object to form a visible image. A magnetic recording method characterized by obtaining. (2) The magnetic recording method according to claim 1, wherein the image particles are transferred to the object by electrostatic force. (3) A magnetic recording toner comprising magnetic particles having magnetism and image particles electrostatically attracted to the surface of the magnetic particles.