JPH0480752A - Image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color image forming apparatus. Specifically, the present invention relates to an image forming apparatus using microcapsule paper coated with microcapsules containing a dye precursor.

[Prior Art] Conventionally, as an image forming apparatus, the following color copying apparatus using microcapsule paper as a photosensitive pressure-sensitive medium has been devised. In this device, a latent image corresponding to a document is first formed on microcapsule paper. Next, particulate color developer is applied to image receiving paper, which may be microcapsule paper or plain paper. Then, the microcapsule paper and the image receiving paper are overlapped. At this time, the color developer is located between the microcapsule paper and the image receiving paper.

This superimposed microcapsule paper and image receiving paper are
Pressure is applied using a pressure roller or the like. Then, when the microcapsule paper and the image-receiving paper are separated, an image is formed on the image-receiving paper. Further, in order to more strongly fix the image on the image receiving paper and to promote color development, the image receiving paper is heated by a heat fixing machine. In this way, the image is fixed on the image receiving paper. In this apparatus, the method for applying a color developer to microcapsule paper or image-receiving paper is as follows. First, a developer toner containing a color developer as a main component is supported on a developer carrier such as a roller. At this time, the developer toner is charged. Further, an electric field is formed between this color developer carrier and the microcapsule paper or the image receiving paper. The charged color developer toner receives an electrostatic force from this electric field and flies toward the microcapsule paper or the image receiving paper. As a result, a color developer is applied.

[Problems to be Solved by the Invention] However, in the image forming apparatus described above, defects have occurred in the images formed on the image receiving paper. That is, in a part of the image area of the image receiving paper, the image was missing and the fabric of the image receiving paper was exposed. This defect is caused by the fact that when the microcapsule paper and receiver paper are separated after pressure development, some of the developed color developer toner and dye do not stick to the receiver paper, but some of them stick to the microcapsule paper. I lived to do it.

To solve this problem, attempts have been made to find a method of heating the image-receiving paper during pressure development in order to preferentially penetrate the molten color developer into the image-receiving paper. However, in order to heat the image receiving paper during pressure development, it is necessary to provide a heating mechanism inside the pressure roller of the pressure development unit. For this reason, a new problem arises in that the mechanical strength of the pressure roller is insufficient, and this method has not been implemented.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide an image forming apparatus that can form defect-free images on image receiving paper.

[Means for Solving the Problems] In order to achieve this object, in the image forming apparatus of the present invention, immediately after microcapsule paper, developer toner, and image receiving paper are superimposed, pressure is applied, and development is performed. First, preheating is performed using a heating mechanism different from the developing machine. This preheating is carried out selectively to the receiving paper. Further, the temperature of this preheating is set so as not to melt the binder of the microcapsule paper. After preheating, the microcave cell paper and the image receiving paper are separated, and the image receiving paper is further subjected to heat fixing at a higher temperature than the preheating.

[Function] In the image forming apparatus of the present invention having the above configuration,
The preheating heats the receiver paper and increases its temperature. Heat conduction also increases the temperature of the developer toner and the microcapsule paper. The color developer toner softens as the temperature rises. Here, since the temperature of the image receiving paper is higher than the temperature of the microcapsule paper, the developer toner penetrates into the inside of the image receiving paper.

After this, when the microcapsule paper and the receiver paper are separated,
Since the developer toner permeates the image receiving paper, the developer toner does not adhere to the microcapsule paper. That is, an image with missing or missing images is formed on the image receiving paper.

Further, since this preheating mechanism is provided separately from the developing machine, the mechanical strength of the developing machine is not impaired.

[Example] Hereinafter, an example embodying the present invention will be described with reference to the drawings. FIG. 1 shows an image forming apparatus 40 of a type in which a mixed color developer toner is applied to image receiving paper.

Inside the casing 46 of the image forming apparatus 40, an exposure unit 41, a color developer application unit 1, a pressure development unit 47, a preheating unit 61, and a heat fixing unit 49 are provided.

The exposure unit 41 includes a halogen lamp 50, a color separation filter 51, and a document table 52. Here, the color separation filter 51 is provided below the halogen lamp 50 and is configured to rotate in accordance with the three primary colors. Further, below the color separation filter 51, an original table 52 for supporting an original is arranged.

The color developer application unit 1 is provided for the purpose of applying color developer toner to the image receiving paper on which an image will finally be formed. The developer coating unit 1 is composed of a carrier roller 31, a conveyor belt 24, an electrode roller 21, and a power source E. The carrying roller 31 is provided to carry and convey the stored developer toner 37. Since the conveyance belt 24 is wrapped around the electrode roller 31, the image receiving paper 22 is conveyed by the electrode roller 21 and the conveyance belt 24. The electrode roller 21 is made of metal and is connected to a power source E. Further, the supporting roller 31 is grounded. For this reason,
An electric field is generated in the space between the support roller 31 and the electrode roller 21, that is, in the transfer area 34. The power supply E is specifically configured to generate a voltage of +1 kV.

The pressure development unit 47 is provided to pressurize the microcapsule paper and the image receiving paper, and is composed of a pair of pressure rollers 55. The preheating unit 61 includes a heating roller 58 in which a rod-shaped halogen lamp is installed.
and a pressing roller 60 for bringing the image receiving paper and microcapsule paper into close contact with the heating roller.

The operation of this device will be explained.

First, the image-receiving paper 22 is taken out from the upper opening of the image-receiving paper cassette 13 by the feed roller 14. Finally,
The image receiving paper 22 is inserted into the developer coating unit 1 through the insertion opening 11 .

The electrode roller 21 and the conveyance roller 23 rotate, and the conveyance belt 24 is driven. The image receiving paper 22 is conveyed to a transfer area 34 by a conveyor belt 24 .

On the other hand, the mixed color developer toner 37 is transferred to the carrier roller 31.
The image is transported to the transfer area 34 by the transfer area 34.

As described above, an electric field is generated in the transfer region 34. In the transfer area 34, the developer toner 37 carried on the carrying roller 31 is subjected to electrostatic force by the electric field. In this embodiment, the developer toner is negatively charged. Therefore, the developer toner receives electrostatic attraction from the electrode roller 21. In this manner, the developer toner is applied to the receiver paper. The image receiving paper 22 coated with the developer toner is delivered to the outside of the developer coating unit 1 through the discharge port 12 . Further, the image receiving paper 22 is conveyed to the pressure developing unit 47 according to the guide roller 54 .

On the other hand, the microcapsule paper 44 is configured to run between the paper feed roll 42 and the take-up roll 43.

First, the microcapsule paper is unwound from the paper feed roll 42 and sent to the exposure unit 41. Next, the microcapsule paper 44 is moved according to the movement of the guide roller 53.
The document is conveyed to the bottom of the document table 52. Next, the halogen lamp 50 is turned on. The light from the halogen lamp passes through the color separation filter 51 and the original. The light that has passed through the original reaches the microcapsule paper located at the bottom of the original table. Microcapsule paper capsules have the property of curing in response to light. Therefore, a latent image corresponding to the original document 45 is formed on the microcapsule paper 44. The microcapsule paper 44 on which the latent image has been formed is conveyed by a guide roller 53 toward a pressure developing unit 47 . Inside the pressure developing unit 47, the microcapsule paper 44
and image-receiving paper 22 are superimposed. At this time, the surface of the microcapsule paper 44 on which the latent image is formed and the developer-coated surface of the image-receiving paper 22 are in contact with each other. Next, the pair of pressure rollers 55 rotate, and the microcapsule paper 44 and the image receiving paper 22 are pressurized. As a result, uncured capsules are destroyed. In the destroyed capsule,
The dye inside will leak out. This dye reacts with the mixed developer toner on the image receiving paper to develop color.

Thereafter, the image receiving paper 22 is conveyed to the preheating unit 61. The halogen lamp 59 installed inside the heating roller 58 of the preheating unit 61 is turned on, and the heating roller 58 is heated by radiant heat. Since the image receiving paper 22 is in contact with the heating roller 58, it is heated. Further, the color developer toner and the microcapsule paper 44 are also heated by thermal conduction.

In the microcapsule paper 44, microcapsules are coated on a base sheet with a binder.

Therefore, the temperature of this preheating must be set lower than the melting temperature of the binder. On the other hand, if the preheating temperature is too low, it will not be effective. Specifically, in this example, the heat fixing temperature of the color developer is 140 to 180°C, and the melting temperature of the binder is about 120°C.
The temperature on the surface of the heating roller is set to 40 to 100°C. In this way, the temperature of the developer toner increases and softens. Since the temperature of the image receiving paper is higher than the temperature of the microcapsule paper, the developer toner penetrates into the inside of the image receiving paper. After this, the microcapsule paper and the receiver paper are separated.

As described above, since the developer toner has permeated the image receiving paper, the developer toner does not adhere to the microcapsule paper, and all the developer is attached to the image receiving paper. In this way, a defect-free image is formed on the receiving paper.

Immediately after preheating, the image receiving paper 22 and the microcapsule paper 44 are heated.
are separated. The image receiving paper 22 is conveyed to the lower part of the thermal fixing unit 49 by a guide roller 56 . Since the image receiving paper is heated by the thermal fixing unit 49, the image is fixed on the image receiving paper 22.

The image receiving paper 22 on which the image has been thermally fixed is moved by a guide roller 57
Accordingly, the image is output to the outside of the image forming apparatus 40.

On the other hand, the microcapsule paper 44 is wound up by a winding roll 43.

[Effects of the Invention] As is clear from the detailed description above, according to the present invention, it is possible to provide an image forming apparatus that can form a defect-free image on image receiving paper.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment embodying the present invention. 370 in the figure. Color developer toner 45, manuscript.

Claims (1)

[Claims] 1. Exposure means for forming a latent image on a photosensitive pressure-sensitive medium, means for applying developer toner to the photosensitive pressure-sensitive medium or image-receiving paper, and superposing the photo-sensitive pressure-sensitive medium, developer toner, and image-receiving paper. In an image forming apparatus that has a developing means that pressurizes the image and a heat fixing means that fixes the image on the image receiving paper, the superimposed photosensitive pressure sensitive medium, color developer toner, and image receiving paper are placed immediately after the developing means. An image forming apparatus comprising a preheating means for heating at a temperature lower than the fixing temperature in the heat fixing means.