JPH05173314A - Image forming device - Google Patents

Abstract

PURPOSE:To provide an image forming device capable of obviating unnecessary consumables so that the running cost may be reduced, and simultaneously attaining an easy handling of microcapsule toner and uniformly coating a supporting body with the toner with a simple constitution. CONSTITUTION:The microcapsule toner 1 sandwiched between a supply belt 36 and a coating belt 40 is rubbed in between both belts, but, both the supply belt 36 and the coating belt 40 have extremely soft elasticity, so that the stress applied on the microcapsule toner 1 is released, then, the microcapsule toner 1 is thoroughly triboelectrostatically charged without being damaged and simultaneously a layer can be controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses microcapsules, and more specifically, microcapsules containing at least a coloring material such as a leuco dye, a colored dye or a pigment as an encapsulating material and having a mechanical strength which changes in response to light. The present invention relates to an image recording device such as a copying machine and a printer.

[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 that reacts with the dye precursor to develop a color is previously applied and the photosensitive medium are overlapped and pressed, and the chemical latent image is developed by pressure, and the image receiving paper is formed. There has been devised an image forming apparatus of a type that fixes an image on a sheet.

As a type of photo-curing, there is a method of obtaining a chemical latent image by photo-polymerizing and curing the microcapsules by irradiation of image light, using a photo-polymerization initiator and a polymerizable compound.
JP-A-57-179836 and JP-A-62-15023
It is disclosed in each gazette of No. 8. Further, a method of forming a latent image nucleus on the photosensitive silver halide by irradiating image light with a photosensitive silver halide, a reducing agent and a polymerizable compound, and then thermally polymerizing and curing the latent image nucleus to obtain a chemical latent image. There are, for example, JP-A-61-278849 and JP-A-62-23.
It is disclosed in each publication of No. 2652.

Further, as another example of the image forming apparatus using the above-mentioned photosensitive medium, the present applicants provide a photosensitive medium on which the above-mentioned chemical latent image is formed and an image-receiving paper which is plain paper with an intermediate color developer layer. Then, a device for forming an image on plain paper by superposing and pressing is devised. Further, an image forming apparatus using a photosensitive medium carrying microcapsules containing a colored dye instead of the above dye precursor is disclosed in JP-A-62-232652.
It is disclosed in the publication.

[0005]

However, in any of the above image forming apparatuses, the photosensitive medium used is a medium in which a plastic film such as PET is used as a support and photosensitive microcapsules are carried on the surface thereof. Met.

This photosensitive medium is collected after use and discarded in a lump, or is cut and discarded each time an image is formed. Therefore, the support, which is not necessary for forming an image, which is originally a plastic film, is consumed, so that the cost of consumables becomes high and the image formation becomes expensive.

When the photosensitive microcapsules are made into toner and handled in an image forming process such as a well-known electrophotographic method, the mechanical strength of the microcapsules is so low that the microcapsules are destroyed in the apparatus. It was very difficult to do so.

In particular, in the case of attempting to charge the microcapsules before curing, the conventional method for frictionally charging an ordinary electrophotographic toner, that is, the method of charging by friction between a rigid body such as a metal blade and the toner is used. However, the microcapsules cannot be endured by this sliding during friction, and the microcapsules are destroyed, causing the serious problem of soiling the inside of the device with the capsule contents. It was very difficult to charge the microcapsules because harmful ozone generated by the discharge is generated.

When the microcapsules are electrostatically coated on the support, if the coating thickness is not uniform, the thin portion causes insufficient coloring, and the thick and multilayered portion corresponds to the white portion of the document. Although all the microcapsules should be cured, the exposure light did not reach the bottom layer of the thick portion and the unexposed microcapsules remained, causing fog in the white background.

The present invention has been made in order to solve the above-mentioned problems, and consumables which are originally unnecessary for image formation are omitted to reduce the running cost and facilitate maintenance, and at the same time mechanically. A microcapsule toner having a low strength can be provided with a sufficient triboelectric charge amount without being broken, facilitating the handling of the microcapsule toner, and uniformly applying the microcapsule toner to a support with a simple structure. An object is to provide such an image forming apparatus.

[0011]

In order to achieve this object, an image forming apparatus of the present invention comprises an encapsulation containing at least a coloring material such as a leuco dye, a colored dye or a pigment, and a resin such as a polymer as main components. An image forming apparatus configured to apply a microcapsule toner composed of a wall member to a support, and at least one of which is composed of a pair of charging members having elasticity and being easily deformable. And a capsule charging means.

[0012]

In the image forming apparatus of the present invention having the above-mentioned structure, the pair of charging members, at least one of which has elasticity and which can be easily deformed, causes friction without destroying the microcapsule toner. Can be charged.

[0013]

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 1 used in the image forming apparatus 10 of the present 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 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 a substance 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 image forming apparatus 10 of the present embodiment has all the movable parts and the light emitting parts (hereinafter abbreviated as movable parts) in the image forming apparatus 10 described in the following embodiments according to the image information signal. Is provided with a control unit 12 for controlling 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 conditions of the movable part and the like with a sensor and the like. is doing.

A document supporting glass 16 is attached to the upper surface of the casing 14 of the image forming apparatus 10. The document is sandwiched between the document supporting 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. An optical system 24 for forming an image and an arithmetic element 26 for converting an electric signal generated by the image light being formed on the solid-state image sensor into an image information signal.
A scanner unit 28 having a and is provided.

When a copy start button (not shown) is pressed, the scanner section 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 while moving the original document. A reading operation is performed, and the read image information signal is transferred to the control unit 12.

The microcapsule toner 1 is stored in the toner case 32 while being shielded from light. The supply belt drive roller 34 has a cylindrical shape and is made of urethane sponge. Supply belt 36 is about 50μ
An m-thick nylon film, the length of which is slightly longer than the circumference of the cross section of the supply belt drive roller 34, and the supply belt 36 is wound around the supply belt drive roller 34 in a somewhat slack form.

In the present embodiment, the material of the supply belt 36 is a nylon film which has a very strong tendency to be positively charged on the charging train and is likely to be negatively charged against the friction partner, but instead of the nylon film. A film made of another material having a strong tendency to be positively charged, such as Teflon, may be used.

The supply belt drive roller 34 rotates in the direction of arrow 37 in response to a command from the control unit 12, and the supply belt 36 also follows this and rotates in the same direction.

By rotating the supply belt 36,
The microcapsule toner 1 is pulled out from the toner case 32.

The coating belt drive roller 38 has a cylindrical shape and is made of metal, and is connected to a high-voltage power source installed inside the control unit 12, and the control unit 12 can be used to Accordingly, a voltage of about + 250V is applied.

The coating belt 40 is a nylon film having a thickness of about 50 μm, and its length is slightly longer than the circumference of the section of the coating belt driving roller 38.
Is wound around the coating belt drive roller 38 in a somewhat slack form.

As the material of the coating belt 40, in this embodiment, a nylon film having a very strong tendency to be positively charged on the charging train and being easily negatively charged against the rubbed partner is used, but instead of the nylon film. A film made of another material having a strong tendency to be positively charged, such as Teflon, may be used.

In FIG. 1, the slack of the supply belt 36 from the supply belt driving roller 34 and the slack of the coating belt 40 from the coating belt driving roller 38 are opposed to each other (inward). The supply belt 36 and the coating belt 40 are held.

In order to hold it in this way, as shown in FIG. 2, the supply belt 36 and the coating belt 40 are pressed from the outside against the supply belt driving roller 34 and the coating belt driving roller 38, respectively, so as to sag outside. The belt guide 42 for restricting not to press is applied from both sides to the both ends of the supply belt 36 and the coating belt 40 which are not involved in image formation from both sides from the direction perpendicular to the paper surface in FIG. There is.

The belt holding method as described above is not limited to the first embodiment, and the same method is used in all the embodiments described below.

The supply belt 36 and the coating belt 40
Are always in pressure contact with each other, but both have extremely soft elasticity in the direction of pressure contact, so that even when one is stopped, the other can freely rotate.

The coating belt drive roller 38 rotates in the direction of arrow 39 in response to a command from the control unit 12, and the coating belt 40 also follows this and rotates in the same direction.

The supply belt drive roller 34 and the application belt drive roller 38 have different peripheral speeds although their rotating directions are opposite to each other. Therefore, the supply belt 36 and the application belt 40 are rotated following them. Is always in friction.

In FIG. 1, microcapsule toner 1
By the action of the rotation of the supply belt 36, the toner is delivered from the toner case 32 to a position where the supply belt 36 and the coating belt 40 are in pressure contact with each other.

The supply belt 36 and the coating belt 40
The microcapsule toner 1 sandwiched between and is rubbed between the supply belt 36 and the coating belt 40 because the peripheral speeds of the supply belt 36 and the coating belt 40 are different from each other. Since both the coating belts 40 exhibit extremely soft elasticity, they alleviate the compressive and shearing stress applied to the microcapsule toner 1, and therefore, the microcapsule toner 1 is not destroyed and is rubbed to a negative polarity with a sufficient charge amount. Can be charged.

The microcapsule toner 1 frictionally charged to the negative polarity is generated by the electric field generated from the coating belt driving roller 38 to which about +250 V is applied.
It is carried on the coating belt 40.

The exposure roller 44 is made of metal and is connected to a high-voltage power source installed inside the control unit 12, and a voltage of about +1 kV is applied from the control unit 12 if necessary. And rotates in the direction of arrow 46.

The microcapsule toner 1 carried on the coating belt 40 is statically placed on the exposure roller 44 by the action of the electric field generated between the coating belt drive roller 38 and the exposure roller 44. It is applied electrically.

The microcapsule toner 1 electrostatically applied on the exposure roller 44 is exposed by the exposure source 48 according to the image information, and by the compression transfer roller 52 rotating in the direction of the arrow 50. Only the above-mentioned microcapsule toner 1 that has been pressed and not photopolymerized and cured is destroyed, and the inclusions containing the coloring material become the compression transfer roller 52.
Carried on top.

Fragments of the microcapsule toner 1 and the photopolymerization cured product remaining on the exposure roller 44 after the pressurization are removed by being slid by the cleaning brush 54 and discarded in the dust box 56.

The image receiving paper 60 stored in the image receiving paper cassette 58 is fed out by the paper feeding roller 62, and the arrow 68 is drawn by the paper guide 64 and the paper guide roller 66.
Is guided in the gap between the nip roller 70 rotating in the direction of and the compression transfer roller 52, is nipped by the nip roller 70 and the compression transfer roller 52, and is pressed,
The inclusion containing the coloring material carried on the pressure transfer roller 52 is transferred onto the image receiving paper 60, and the image is transferred onto the image receiving paper 6
Form on 0.

The image receiving paper 60 having the formed image.
Is guided by the paper discharge roller 72 and discharged to the exit tray 74.

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. In the drawings for explaining the modified examples described below, the same members as those in the first embodiment shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

For example, in the above embodiment, the supply belt 36 and the coating belt 40, which are a pair of charging members, rotate in different directions as indicated by arrows 37 and 41, but they may rotate in the same direction. Good.

In the image forming apparatus 110 shown in FIG. 3, the supply belt 36 and the coating belt 40 rotate in the same direction as indicated by arrows 137 and 141. In this case, setting the supply belt 36 and the coating belt 40 at a certain relative speed to control the triboelectric charge amount can be achieved by a simpler method than in the above-described embodiment.

That is, in the above embodiment, since the relative speed is the difference between the peripheral speeds of the supply belt 36 and the coating belt 40, it is necessary to control both peripheral speeds. The drive control of both the motor (not shown) connected to 34 and the motor (not shown) connected to the application belt drive roller 38 must be performed by separate systems.

On the other hand, in the case of FIG. 3, if the feeding belt driving roller 34 and the coating belt driving roller 38 have the same size, the peripheral speeds of the feeding belt 36 and the coating belt 40 are the same, and the relative speeds are the same. It will be double the peripheral speed on one side. Therefore, the motor (not shown) connected to the supply belt drive roller 34 and the application belt drive roller 3
If the motors (not shown) connected to 8 are the same motor, both may be driven at the same number of revolutions, and therefore both drive controls can be performed by the same system.

Further, in the above embodiment, both the pair of charging members have elasticity, but it is also possible to have a structure in which only one has elasticity.

In the image forming apparatus 210 shown in FIG.
Of the pair of charging members, the supply roller 234, which is the charging member on the toner supply side, is made of metal and is softly pressed against the coating belt 40. The image forming apparatus 210 configured as described above is configured so that the supply roller 2 from the toner case 32 is supplied.
It becomes easy to attach and detach 34, and therefore it becomes very easy to perform maintenance activities such as replacement and cleaning of parts, replacement and replenishment of microcapsule toner, and to reduce the cost for image formation with a simple configuration. It has the feature that

Further, in the image forming apparatus 310 shown in FIG. 5, of the pair of charging members, the coating roller 338, which is the charging member on the electrostatic coating side of the toner, is the resin coating layer on the surface of the mandrel made of metal. A roller having a feeding belt 3
It is pressed against 6 softly. In the image forming apparatus 310 having the above-described configuration, it is extremely preferable that the gap distance between the application roller 338 and the exposure roller 44, which is related to the electric field strength during electrostatic application of the microcapsule toner 1, is always constant. It will be easier and therefore the application roller 33
8 and the exposure roller 44 constant electric field strength,
The microcapsule toner 1 is applied onto the exposure roller 44 in a stable amount with a simple structure, and it is possible to suppress uneven density and perform stable image formation.

In the above embodiment, a loose belt-like belt is used as the elastic charging member, but a roller having rubber, sponge or the like on the surface, nylon, PET or the like is used. A hollow tube made of a resin film filled with a fluid such as water or oil may be used.

[0054]

As is apparent from the above description, according to the present invention, consumables which are not originally necessary for image formation are omitted to reduce the running cost and facilitate maintenance, and at the same time, the mechanical strength is improved. A microcapsule toner having a low viscosity can be provided with a sufficient triboelectric charge amount without breaking, facilitating the handling of the microcapsule toner and uniformly applying it to a support with a simple structure. An image forming apparatus can be provided.

[Brief description of drawings]

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

FIG. 2 is a diagram showing only a main part thereof.

FIG. 3 is a schematic diagram of a configuration showing a second embodiment of the present invention.

FIG. 4 is a schematic diagram of a configuration showing a third embodiment of the present invention.

FIG. 5 is a schematic diagram of a configuration showing a fourth embodiment of the present invention.

[Explanation of symbols]

 1 Micro Capsule Toner 36 Supply Belt 37 Arrow 40 Coating Belt 41 Arrow 44 Exposure Roller 48 Exposure Source 52 Pressure Transfer Roller 137 Arrow 141 Arrow 234 Supply Roller 338 Coating Roller

Claims (1)

[Claims] 1. A microcapsule toner composed of an inclusion containing at least a coloring material such as a leuco dye, a colored dye or a pigment, and a wall member containing a resin such as a polymer as a main component is applied to a support. In the image forming apparatus described above, at least one of them is provided with a capsule charging unit composed of a pair of charging members that are elastic and easily deformable.