JPH04318547A - Image recorder - Google Patents

Abstract

PURPOSE:To provide a recorder forming an image without wasting any developer toner and where weather resistance is inconspicuous by having only parts of images and characters formed on an arbitrary recording medium coated with the developer toner in a recorder with a pressure sensitive recording medium. CONSTITUTION:The principle is coloring by the reaction of an image former such as color or color precursor with a developer. The pressure sensitive recording medium 1 is selectively coated with developer toner utilizing a method making use of a photosensitive body or a method making use of a multi stylus head. When the pressure sensitive recording body l coated with the developer toner is pressurized and fixed by being superposed with the medium to be recorded, an image is formed by the developer toner where the image former is colored being fixed on the body to be recorded.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to an image recording device.
In particular, the present invention relates to an improvement in an image recording apparatus using an image forming system that develops color on a pressure-sensitive recording medium through the action of an image forming agent such as a dye precursor and a developer such as a color developer.

0002

[Prior Art] Conventionally, a coloring reaction has been applied based on the transfer of electrons between an electron-donating colorless dye or dye precursor or other image forming agent and an electron-accepting developer such as a color developer. The color is developed on a pressure-sensitive recording medium. A colorless image forming agent encapsulated in microcapsules supported on a pressure-sensitive recording medium ruptures and flows out due to mechanical destruction, and reacts with a developer to color the dye and the like to form an image.

A color developer, which is a developer, is dispersed in the form of ultrafine particles in an aqueous solvent. A developer sheet, which is a special paper, is produced by adding an adjusted binder, additives, etc. to this color developer and applying it to the paper that has been made. Also,
In order to avoid providing the developer sheet as special paper to users, there is also a method of powdering the developer (developer toner) and applying it electrostatically.

The latter method of using developer toner is to form a developer sheet in an apparatus by electrostatically transferring the developer toner onto an arbitrary recording medium (recording medium), An image was formed on any recording medium by superimposing microcapsule paper on the paper and fixing it under pressure. The electrostatic transfer is performed by causing developer toner to fly. For the flight of the developer toner, a carrier for the developer toner and a back electrode (or a potential having the same effect as the back electrode) placed opposite the carrier via an arbitrary recording medium are used.
An electric field is required between the The color developer toner electrostatically flew onto the arbitrary recording medium in this way, and is coated on the entire surface of the arbitrary recording medium with the length of the width of the color developer toner carrier.

[0005]

[Problems to be Solved by the Invention] However, when applying the developer toner to the entire surface, the developer toner is electrostatically applied to areas where images, characters, etc. are not formed, and the developer toner is It is fixed on any recording medium without exhibiting its original coloring function. This is a waste of developer toner, and the output image (hard copy) 1
The cost per piece also increases. Further, the color developer toner fixed on any recording medium changes color when exposed to light or the atmosphere. Discoloration of the developer toner reduces image contrast and impairs the shelf life of the developer toner layer formed on any recording medium.

[0006] In order to solve the above problems, the present invention has the following features:
It is an object of the present invention to provide an image recording device that eliminates waste of color developer toner and has good weather resistance.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for causing the image forming agent to flow out by destroying the microcapsules of a pressure-sensitive recording medium carrying the microcapsules containing the image forming agent. In an image recording device that reacts with a developer to develop color, the image recording device is provided with selective application means for selectively applying the developer to microcapsules corresponding only to portions of a document where characters and images, which are image information, are present; The pressure sensitive recording medium on which the developer is selectively applied by the selective application means and the image forming agent are pressure developed to cause a color reaction and to obtain the image information on the recording medium.

[0008]

[Operation] According to the present invention, characters and
A developer (color developer toner) is selectively applied only to the microcapsules on the pressure-sensitive recording medium in areas corresponding to image information such as images. When this selectively applied state is subjected to pressure development together with the recording medium, all the microcapsules on the pressure-sensitive recording medium are destroyed, but the only microcapsules that develop color are those to which the developer has been selectively applied. Therefore, since there is no unreacted developer on the recording medium, no discoloration occurs.

[0009]

Embodiments Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. As shown in FIG.
is composed of an exposure device 10, a developing device 20, a transfer device 30, and the like. A document table 4 is arranged on the upper surface of the housing C, and the document 3 is supported on the lower surface side of the document table 4. The document table 4 supporting the document is driven left and right by a drive means (not shown).

The exposure device 10 is disposed below the document table 4, and the light emitted from the light source 9 is emitted directly or through a reflecting mirror 9.
1 and reaches the document 3. The light reflected by the original 3 reaches a photoreceptor 43, which is located below and serves as selective coating means according to the gist of the present invention. Pressure sensitive recording medium 1
is supplied from a supply roller 5 disposed at the lower right, and is taken up by a take-up roller 7 via a predetermined travel path and a pressure fixing roller 7. The photoreceptor 43 is driven to rotate clockwise, and a charger 26 that uniformly charges the surface of the photoreceptor 43 is provided near the upper left of the photoreceptor 43, and a toner collection case 41 is provided near the lower left. has been done. A toner collection blade 42 is installed in the toner collection case 41 and is configured to peel off the developer toner remaining on the surface of the photoreceptor 43.

Here, the photoreceptor 43 and the pressure-sensitive recording medium 1 will be explained based on FIGS. 2(A) and 2(B). As shown in FIG. 2A, the photoreceptor 43 has a photoconductive layer 43a that becomes conductive when irradiated with light of a predetermined intensity is disposed on the outer shell, and a conductive layer 43b is disposed on the inner surface of the photoconductive layer 43a. established and configured. The conductive layer 43b is grounded.

As shown in FIG. 2(B), a pressure-sensitive recording medium 1
Leuco, which is an image forming agent such as crystal violet lactone or 3-diethylamino-7-chlorofluorane, is applied to the surface of a plastic film base material 11 such as polyethylene terephthalate or polypropylene, which develops color by reacting with the color developer toner 25. Microcapsules 12 containing dyes or dye precursors are supported. The microcapsules 12 collapse when mechanical pressure is applied, and the encapsulated image forming agent flows out and reacts with the color developer toner 25 to develop color.

The developing device 20 is disposed on the right side of the housing C, and a developer toner 25 is stored inside a toner case 24 . A supply roller 22 is disposed inside the toner case 24, and the supply roller 22 causes the developer toner 25 to be carried on a roller-shaped carrier 21 disposed on the left side. The supply roller 22 is preferably made of an elastic and soft material, such as a sponge roller, in order to supply the developer toner 25 without crushing it. Carrier 21
may be either a conductor or an insulator, and the surface of the carrier 21 is roughened to improve the efficiency of conveying the developer toner 25. A blade 23 is disposed near the top of the supply roller 22 to adjust the thickness of the developer toner 25 attached to the outer peripheral surface of the supply roller 22 . The blade 23 is preferably made of a harder material than the material of the supply roller 22. The color developer toner 25 is subjected to friction and sliding by various parts constituting the developing device 20, and is negatively charged.

The transfer roller 31 constituting the transfer device 30 is provided below the photoreceptor 43 with a small gap therebetween.
It is connected to the positive electrode of the battery 31a. A cassette 33 containing a stack of recording media 2 is disposed at the upper left of the housing C, and the recording media 2 are taken out one by one from the top by a suction cup device (not shown) and sent along a guide plate 35 to a pressure fixing roller 7.

Next, the operation and configuration of the parts related to the gist of the present invention will be explained. First, the operation of developing the developer toner 25 on the photoreceptor 43 will be explained based on FIG. 2(A). As shown in FIG. 2(A), the photoreceptor 4 is charged by the charger 26.
The surface of 3 is charged with a positive uniform charge. Light projected from light source 9 is reflected by document 3, and this reflected light is given to photoreceptor 43 as image information. Then, the photoconductive layer 4
3a becomes a conductor, and the positive charge existing on the surface of the photoreceptor 43 flows to the ground (earth) via the photoconductive layer 43a and the conductive layer 43b, and only the portion irradiated with light has a surface charge. An electrostatic latent image is formed in which no . In the portions that were not irradiated with light, the positive surface charges were not removed and remained. When the carrier 21 carrying the developer toner 25 approaches the photoreceptor 43 in this state, the developer toner 2
5 flies, and a developer toner 25 forms a developed image on the photoreceptor 43 in accordance with the electrostatic latent image. That is, the photoreceptor 4
3, the color developer toner 25 necessary only for forming characters and images remains. Therefore, since pressure transfer, which will be described later, is performed in this state, no developer toner unrelated to color development remains on any recording medium.

The developer toner 25 used in the present invention is
The main component is a dye receptor that develops color by reacting with an image forming agent, such as natural clay minerals such as acid clay, bentonite, and attapulgide; organic acids and their esters such as tannic acid, gallic acid, and propyl gallate; Acidic polymers such as phenolic resins, maleic acid resins, phenol-acetylene resins, condensation products of formaldehyde and carboxylic acids having at least one hydroxy group; zinc salicylate, tin salicylate, zinc 2-hydroxynaphthoate, 3,5 -Zinc di-t-butylsalicylate, 3,
Metal salts of aromatic carboxylic acids such as zinc 5-di(α-methylbenzyl)salicylate; metal salt-modified phenolic resin compounds modified with polyvalent metals such as zinc and nickel; and the like.

When the developer toner 25 is applied only to the pressure-sensitive recording medium 1 and fixed to the recording medium 2 under pressure, the developer toner 25 is surely applied to the recording medium 2. Since it is not fixed and remains on the pressure-sensitive recording medium 1 side, gaps occur in the image on the recording medium 2. Therefore, a material is mixed into the color developer, which is the dye receiver, to give it a pressure fixing ability that allows it to adhere only to the recording medium 2 side. The pressure fixing performance of the color developer toner 25 on the recording medium 2 is related to the entanglement and adhesiveness of its constituent components, and by mixing wax and adhesive with good compatibility and adhesiveness with the color developer. , pressure fixing performance can be improved.

The above color developer component and pressure fixing component are melt-kneaded and pulverized, and if necessary, classified to form one particle, and a color developer toner having a volume average particle diameter of 5 to 50 μm is prepared. 2
form 5. Further, as shown in FIG. 2(B), the pressure fixing roller 7 crushes the microcapsules 12, causes the encapsulated image forming agent to flow out, causes the image forming agent to interact with the color developer toner 25, and causes the image forming agent to develop color. The color developer toner 25 impregnated with the colored image forming agent is transferred from the pressure-sensitive recording medium 1 to the recording medium 2 and is fixed to the recording medium 2 under pressure. The pressure fixing roller 7 is formed by two cylindrical rollers, and an auxiliary roller (
(not shown) applies the pressure necessary for pressure fixing.

Next, the general operation of the image recording apparatus of this embodiment will be explained. First, the charger 26 charges the pressure-sensitive recording medium 1.
A positive surface potential is applied to the surface. In synchronization with this, the light from the light source 9 and the light from the reflecting mirror 91 are focused on the original 3, and the reflected light from the original 3 illuminates the surface of the photoreceptor 43 as image information. The document 3 is conveyed by a driving means (not shown), and the pressure-sensitive recording medium 1 is also conveyed, and exposure is started from a portion to which a surface potential is applied by the charger 26.

The developer toner 25 is negatively charged by friction within the developing device 20, and the amount of developer toner 25 that adheres to the carrier 21 is regulated by a blade 23 on the supply roller 22. Carrier 21
The amount of developer toner 25 that is adhered to and conveyed on the photoreceptor 43 limits the amount of developer toner 25 that is conveyed while adhered to the photoreceptor 43 . Since the developer toner 25 conveyed onto the carrier 21 applies a positive potential to the surface of the photoconductor 43 according to the image information of the document, the negatively charged developer toner 25 is applied along the electric field. and flies to the photoreceptor 43. The developer toner 25 makes latent images such as characters on the photoreceptor 43 visible. This image development is carried out by the transfer roller 31 to which a positive potential is applied.
The developer toner 25 on the photoconductor 43 pressed by
The image is transferred to the pressure-sensitive recording medium 1. The developer toner 25 remaining on the photoreceptor 43 without being transferred to the pressure-sensitive recording medium 1 is transported as it is, scraped off from the photoreceptor 43 by the toner collection blade 42, and stored in the toner collection case 41. .

Color developer toner 2 attached to pressure-sensitive recording medium 1
5 is overlapped with the recording medium 2 by the pressure fixing roller 7 and pressure is applied thereto, and then transferred to the recording medium 2 and fixed. The microcapsules 12 are crushed by the pressure fixing roller 7, and the encapsulated image forming agent flows out.
The dye precursor permeates into the developer toner 25 that has adhered to the pressure-sensitive recording medium 1 by electrostatic force, develops color, and is transferred to the recording medium 2. When observed through this transfer, it appears that the developer toner 25 has developed color.

The transfer rate of the developer toner 25 to the recording medium 2 largely depends on the wettability of the developer toner 25 on the surface of the pressure-sensitive recording medium 1 and the recording medium 2, and depends on the fixing component. Depending on the nature, 100% transfer is possible. In the image obtained in this way, since the white part is not coated with the color developer toner 25, it has good storage stability against light, makes discoloration less noticeable, and also has image forming parts and non-image parts. An image with sharp contrast can be obtained.

In this embodiment, a case has been described in which the photoreceptor 43 is positively charged and the developer toner 25 is negatively charged, but these polarities may be reversed. In addition, as a selective application means, a multi-stylus with electrodes arranged in a horizontal line and a back electrode are placed opposite each other, a pressure-sensitive recording medium is interposed between the multi-stylus and the back electrode, and pressure-sensitive recording is performed using electrostatic force. A developer toner corresponding only to image information may be supported on the medium.

Furthermore, a color developer toner corresponding only to the characters/images of the image information may be attached to the recording medium, and a color developing reaction may be caused with the microcapsules of the pressure-sensitive recording medium.

[0025]

[Effects of the Invention] As explained above, according to the present invention, for example, developer toner is applied to a pressure-sensitive recording medium only in the area corresponding to characters/images, and only that area is colored. Therefore, only a small amount of developer toner is required, and since no developer toner is present on the recording medium, there is no discoloration.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an image forming apparatus to which the present invention is applied.

[Figure 2] (A) is a diagram illustrating a state in which developer toner flies due to electrostatic force to a part of the photoreceptor that is not irradiated with light, and (B) is a diagram illustrating a situation in which microcapsules are crushed and color develops. FIG.

[Explanation of symbols]

1...Pressure sensitive recording medium 2...Recording medium 3...Manuscript 4...Light source 10... Exposure device 11...Plastic film base material 12...Microcapsule 20...Developing device 21...Support 25...Developer toner (developer) 26... Charger 30...Transfer device 43...Photoreceptor (selective coating means) 43a...Photoconductive layer 43b...Conductive layer

Claims (1)

[Claims] 1. An image recording apparatus in which the microcapsules of a pressure-sensitive recording medium carrying microcapsules containing an image forming agent are ruptured to cause the image forming agent to flow out and react with a developer to develop color. A pressure-sensitive recording device comprising selective application means for selectively applying the developer to microcapsules corresponding only to portions of the document where characters and images, which are image information, are present, and in which the developer is selectively applied by the selective application means. An image recording apparatus characterized in that the image information is obtained on the recording medium by subjecting the medium and the image forming agent to pressure development to cause a color reaction.