JPH0635159A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent an image from being stained and to prevent noise from occurring with simple constitution by destroying microcapsure toner while the microcapsule toner is attracted to magnetic carrier powder and granular materials. CONSTITUTION:The microcapsule toner 1 coating a developing roller 37 is exposed by an exposure light source 48 controlled with a control unit 12 according to image information read by a scanner part 28 and continuously pressure- developed by being pressured with a pressure developing and transfer roller 50 rotated clockwise. At the pressure developing time, the toner 1 which is not hardened is destroyed and the included material thereof including a coloring material is transferred on the roller 50. However, an unnecessary material such as the residual wall component of the destroyed toner 1 or the hardened toner 1 is restricted to the magnetic carrier 2 by electrostatic attracting force. Thus, the unnecessary material is not attached to the roller 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly to a microcapsule which contains at least a coloring material such as a leuco dye, a colored dye or a pigment as an encapsulation, and whose mechanical strength changes in response to light. It relates to the copying machines and printers used.

[0002]

2. Description of the Related Art Conventionally, a photosensitive medium coated with microcapsules containing a dye precursor and a photocurable substance is exposed on the basis of image information, and the microcapsules are cured to form a chemical latent image on the photosensitive medium. Then, the image receiving paper on which the color developing agent which reacts with the dye precursor and develops color in advance and the photosensitive medium are superposed and pressed, and the chemical latent image is developed by pressure to form an image receiving paper. An image forming apparatus of a type that fixes an image is known.

As a type of photo-curing, there is a method of obtaining a chemical latent image by photo-polymerizing and curing the microcapsules by using a photo-polymerization initiator and a polymerizable compound and irradiating light according to image information. It is disclosed in Japanese Laid-Open Patent Publication No. 63-316038. The progress of the photoreaction is determined by an initiator that generates a reactive species such as a radical upon irradiation with light, and a wavelength that is added for advancing the photoreaction by absorbing light of a predetermined wavelength and transmitting the energy to the initiator. It is carried by a sensitizer.

Further, as a method for improving the sensitivity of photopolymerization and curing by improving the above-mentioned constitution, a photosensitive silver halide, a reducing agent and a polymerizable compound are used, and the photosensitive halogen is irradiated by irradiation of light according to image information. There is a method in which a latent image nucleus is formed on silver halide and then heat-polymerized and cured by heating to obtain a chemical latent image, for example, JP-A-61-278849 and JP-A-62-2.
It is disclosed in Japanese Patent No. 32652 and the like.

In any of the above image forming apparatuses,
Image formation was possible only on a special paper having a developer layer on the surface.

As a different example of the image forming apparatus using the above-mentioned photosensitive medium, the present applicant has overlaid the photosensitive medium on which the above-mentioned chemical latent image is formed and the image receiving paper which is plain paper with the developer layer in the middle. We have devised a device that pressurizes together and forms an image on plain paper. Further, an image forming apparatus using a photosensitive medium carrying microcapsules containing a colored dye instead of the dye precursor is disclosed in JP-A-62-232652.

However, in any of the image forming apparatuses described above, the photosensitive medium used is a plastic film such as PET as a support, and a binder aqueous solution in which a binder such as PVA is dissolved in a suitable solvent on the surface of the support. A microcapsule slurry having photosensitive microcapsules dispersed therein was applied and dried to obtain a photosensitive medium in which the photosensitive microcapsules were fixed on a support.

This photosensitive medium is collected after use and discarded in a lump, or only the used portion is cut and discarded each time an image is formed. Therefore, the support, which is not necessary for forming an image, which is a plastic film, is consumed, resulting in a high cost of consumables and a high image forming cost.

In order to solve the above-mentioned problems, the applicant of the present invention converts a photosensitive microcapsule into a toner, and coats it on a support by an image forming process such as a well-known electrophotographic method. An image forming apparatus having a configuration in which only the consumption is consumed is disclosed in the specification and drawings attached to the application of Japanese Patent Application No. 3-124919.

In the above image forming apparatus, image formation is performed as follows.

First, triboelectrically charged photosensitive microcapsule toner is applied onto a support by flying using a DC electric field.

Next, the microcapsule toner coated on the support is irradiated with light according to the image information to photopolymerize and cure the microcapsule toner according to the image information.

Then, the dye / pigment is transferred to the transfer medium side together with the inclusion by applying a pressure to the transfer medium which temporarily supports the inclusion, and the pressure is applied (this process is called pressure development or expression). All the microcapsule toner that does not contribute to color development due to the capsule wall or the curing is left on the support, and these are removed later with a cleaner or the like.

Then, an image receiving paper is superposed on the transfer medium carrying the inclusions, and the inclusions carried on the transfer medium are retransferred to the image receiving paper side by using an action such as pressing or heating. Thus, the desired image is formed on the image receiving paper.

[0015]

However, in the conventional image forming apparatus as described above, it is possible to successfully separate the inclusions such as the coloring material and the unnecessary substances such as the hardened capsule and the broken capsule wall during the pressure development. Nothing that is not necessary for image formation, such as the broken capsule wall that should remain on the support and the microcapsule toner that did not contribute to color development due to curing, are erroneously transferred to the transfer medium, and this is transferred to the receiving paper side. There is a problem that the transferred image causes stains and noises on the formed image.

The present invention has been made in order to solve the above-mentioned problems, and improves the separation failure between the inclusions such as coloring materials and the unnecessary substances such as hardened capsules and broken capsule walls during pressure development. Another object of the present invention is to provide an image forming apparatus capable of preventing image stains and noise with a simple configuration.

[0017]

To achieve this object, the image forming apparatus of the present invention comprises at least a magnetic carrier powder containing a magnetic material as a main component, and at least a leuco dye.
A microcapsule toner composed of an inclusion containing a coloring material such as a colored dye or pigment and a polymerizable substance, a wall member containing a dielectric such as a polymer as a main component, and a support provided with at least a magnetic field generating means. Body, capsule applying means for adsorbing the microcapsule toner to the magnetic carrier powder carried by magnetic attraction on the support by electrostatic attraction, and electrostatic charging of the microcapsule toner to the magnetic carrier powder. And a destruction means for destroying the microcapsule toner while maintaining the state of being attracted by the attractive force.

[0018]

In the image forming apparatus of the present invention having the above-mentioned structure, the magnetic carrier powder containing a magnetic material as a main component is carried by magnetic attraction on the support having at least the magnetic field generating means, and the capsule applying means is provided. Means to adsorb the microcapsule toner to the magnetic carrier powder by electrostatic attraction, and the destructing means holds the microcapsule toner while holding the state where the microcapsule toner is adsorbed to the magnetic carrier powder by electrostatic attraction. Destroy.

The destroyed microcapsule toner can satisfactorily separate the unwanted matter adsorbed on the magnetic carrier powder by electrostatic attraction from the inclusions containing the coloring material, and therefore, the image receiving paper can be separated. No dirt or noise will occur.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a configuration showing an embodiment of an image forming apparatus embodying the present invention.

The microcapsule toner 1 used in the image forming apparatus 10 of the embodiment is composed of a wall material portion and a liquid component which is an inclusion thereof, and the liquid component cures in response to at least a predetermined wavelength. It contains a photocurable substance and a pigment as a coloring material.

Examples of the photo-curable substance include polymerizable compounds such as N-vinyl-2-pyrrolidone, bisphenol A diacrylate and methacrylate, tripropylene glycol diacrylate and methacrylate, polyethylene glycol diacrylate and methacrylate, penta. Examples thereof include erythritol triacrylate and methacrylate, dipentaerythritol hexaacrylate and methacrylate, trimethylolpropane triacrylate and methacrylate, oligoester acrylate and methacrylate and the like. Further, these polymerizable compounds may be used alone or as a mixture of two or more kinds. Usually, these polymerizable compounds and a photopolymerization initiator are used in combination.

The photopolymerization initiator is one which is sensitive to light and initiates the polymerization of the resin. For example, benzoyl alkyl ethers such as benzophenone and benzoyl isopropyl ether, Michler's ketone, metal arene compounds,
2,4-diethylthioxanthone and the like can be mentioned.

The microcapsule toner 1 having the above structure is
It can be produced by a method already known in the art. For example, US Pat. No. 2,800
No. 457, No. 2800458, etc., a method for phase separation from an aqueous solution, Japanese Patent Publication No. 38-1974,
In-situ by the interfacial polymerization method as shown in JP-A-42-446, JP-A-42-771 and the like, and the polymerization of monomers shown in JP-B-36-9168 and JP-A-51-9079. Method and the melt dispersion cooling method shown in British Patent Nos. 952807 and 965074, but are not limited thereto.

Further, according to the above-mentioned manufacturing method, the particle size of the microcapsule toner 1 having the above-mentioned structure is several to 100 μm.
It can be arbitrarily adjusted within the range of m.

As a material for forming the wall material, gelatin, gum arabic, starch, sodium alginate, polyvinyl alcohol, polyethylene, polyamide, polyester, polyurethane, polyurea, polyurethane,
Polystyrene, nitrocellulose, ethyl cellulose,
Methyl cellulose, melamine-formaldehyde resin,
A urea-formaldehyde resin or the like is used, but a material that allows sufficient light transmission is more preferable.

The magnetic carrier 2 used in the image forming apparatus 10 of the embodiment may be a powder having the same structure as the magnetic carrier used in the electrophotographic two-component developing method which is a known technique, such as iron powder or resin. Although ferrite coated with, a polymer powder in which magnetic fine particles are dispersed, or the like can be used, the diameter is preferably about several tens of μm.

The image forming apparatus 10 of the embodiment is an image forming apparatus 1 described in the following embodiment according to an image information signal.
A control unit 12 is provided to control all movable parts and light emitting parts (hereinafter abbreviated as movable parts) in 0 so as to operate properly for image formation.

The control unit 12 controls the movable part and the like by sending a command to a driver, a switch and the like connected to the movable part and the like while monitoring the operating condition of the movable part and the like with a sensor and the like. is doing.

In the image forming apparatus 10, a document support glass 16 is attached to the upper surface of the casing 14. The document is sandwiched between the document support glass 16 and the document retainer 18 and held so that the image surface faces downward.

Below the document supporting glass 16, a light source lamp 20 for illuminating the document, a solid-state image pickup device 22 for reading the reflected light from the document, and a reflected light from the document on the solid-state image pickup device. A scanner unit 28 having an optical system 24 for forming an image and an arithmetic element 26 for converting an electric signal generated by forming an image of light according to image information on the solid-state image pickup device into an image information signal. Is equipped with.

When a copy start button (not shown) is pressed, the scanner unit 28 moves in the direction of arrow 30 by a motor (not shown) or the like in accordance with an instruction from the control unit 12 to move the original document. The reading operation is performed and the read image information signal is transferred to the control unit 12.

The capsule coating device 31 includes at least a toner case 32, a stirring case 33, a supply roller 34, a spike height regulating plate 35, and a stirring roller 36.

The microcapsule toner 1 is stored in the toner case 32 while being shielded from light. The stirring case 33 is also made of a light-shielding material and houses the magnetic carrier 2.

The toner case 32 and the agitation case 33 are usually integrally formed of the same material, but even when they are separately formed, they are bonded and connected.

The toner case 32 and the stirring case 33 are separated by a supply roller 34, and the toner case 32 is rotated by the clockwise rotation of the supply roller 34.
Microcapsule toner 1 is stirred from inside Case 33
Is configured to be supplied within.

The supply roller 34 is cylindrical in shape and has a diameter of φ1.
About 0 mm, the material is urethane sponge.

The height control plate 35 is a plate material made of nylon resin having a thickness of about 1 to 2 mm, and a developing roller 37 described later.
It is installed so that the gap between and is about 50 μm.

The stirring roller 36 is a metal core rod having a diameter of about 5 mm and a stirring blade made of wire or the like attached thereto. The metal core rod of the stirring roller 36 is grounded.

By rotating the supply roller 34 in the clockwise direction in FIG. 1, the microcapsule toner 1 is pulled out from the toner case 32 and supplied to the stirring case 33.

In the stirring case 33, the stirring roller 36 is rotating clockwise in FIG.
The microcapsule toner 1 and the magnetic carrier 2 are rubbed, and the microcapsule toner 1 is charged and electrostatically adheres to the magnetic carrier 2.

The developing roller 37 is composed of a magnet roller 38 which is composed of a magnet which is a magnetic field generating means, and a non-magnetic fluororesin which is provided on the magnet roller 38 and has excellent releasability. Transport sleeve 39
The developing roller 37 rotates counterclockwise in FIG.

In the portion where the developing roller 37 and the stirring case 33 are in contact with each other, the magnetic carrier 2 that electrostatically adsorbs the microcapsule toner 1 is carried on the developing roller 37 by magnetic force, and the spike height regulating plate 35. The supported amount is regulated by.

As described above, the microcapsule toner 1 applied on the developing roller 37 is exposed by the exposure source 48 controlled by the control unit 12 according to the image information read by the scanner unit 28, Subsequently, it is expressed by being pressed by the pressing transfer roller 50 rotating clockwise in FIG.

At the time of pressing, the uncured microcapsule toner 1 is broken and the inclusions containing the coloring material are transferred onto the pressing transfer roller 50, but the remaining wall of the broken microcapsule toner 1 is transferred. Since the members and unnecessary substances such as the hardened microcapsule toner 1 are bound to the magnetic carrier 2 by electrostatic attraction, these unnecessary substances do not adhere to the pressure transfer roller 50, and therefore these unnecessary substances are not adhered. It is possible to prevent the image from being stained.

Further, these unnecessary substances remaining on the developing roller 37 after the pressure development are cleaned by the cleaning unit 54.
Removed by.

The cleaning unit 54 includes a high voltage roller 56 connected to a high voltage power source and a cleaning belt 58 made of a releasing insulating material such as silicon rubber.
Cleaning blade 60 and dust box 62
It consists of and.

The charged unwanted matter adhering to the magnetic carrier 2 flies by the high electric field generated by the high voltage roller 56, moves onto the cleaning belt 58, is scraped off by the cleaning blade 60, and is dusted to the dust box 62. Be thrown away.

The image receiving paper 70 stored in the image receiving paper cassette 68 is fed out by the paper feeding roller 72, guided by the paper guide 74 into the gap between the nip roller 80 and the compression transfer roller 50, and the nip thereof. Roller 8
0 and the pressure transfer roller 50 are pressed and pressed, and the inclusion containing the coloring material carried on the pressure transfer roller 50 is transferred onto the image receiving paper 70, and the image is transferred onto the image receiving paper 70. Form on top.

The image receiving paper 70 having the formed image.
Is guided by the paper ejection guide 81 and the paper ejection roller 82,
It is discharged to the outlet tray 84.

As described above, the microcapsule toner is electrostatically adsorbed on the magnetic carrier powder, and when the microcapsule toner is developed by pressure or the like, the microcapsule toner is constrained to the magnetic carrier to carry out the inclusion. It is possible to favorably separate unnecessary substances such as a wall member and a cured product from each other, and thus it is possible to prevent image stains and noise caused by adhesion of the unnecessary substances to the output image.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, in the present embodiment, pressure was used as a means for destroying the microcapsule toner.
Electromagnetic force or the like may be used.

The material, rotation direction and movement direction of each member such as the roller in the above embodiment are not limited to those described above.

[0056]

As is apparent from the above description, according to the present invention, unnecessary substances such as broken capsule walls and microcapsule toners that did not contribute to coloring by curing and inclusions such as coloring materials. Can be favorably separated, and therefore, it is possible to prevent image stains and noise caused by the transfer of unwanted matter to the image receiving paper side with a simple configuration.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a configuration showing an embodiment of the present invention.

[Explanation of symbols]

 1 Microcapsule Toner 2 Magnetic Carrier 31 Capsule Coating Device 37 Development Roller 50 Pressure Transfer Roller 80 Nip Roller

Claims (1)

[Claims] 1. A magnetic carrier powder containing a magnetic material as a main component, an inclusion containing at least a coloring material such as a leuco dye, a colored dye or a pigment, and a polymerizable substance, and a dielectric material such as a polymer. A microcapsule toner composed of a wall member as a main component, a support having at least a magnetic field generating means, the magnetic carrier powder carried by magnetic attraction on the support, the microcapsule toner Capsule applying means for adsorbing the microcapsule toner by electrostatic attraction, and destruction means for destroying the microcapsule toner while holding the state where the microcapsule toner is attracted to the magnetic carrier powder by electrostatic attraction. An image forming apparatus characterized by.