JPH03237449A - Fullcolor 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 fa) Industrial Field of Application This invention is a method for producing full-color images using a photosensitive sheet in which a plurality of types of microcapsules, each sensitive to light of different wavelengths, are coated on the same base sheet in an evenly distributed amount. The present invention relates to an image forming apparatus that forms an image.

(bl) Conventional technology There is a method of forming full-color images using a photosensitive sheet coated with several types of microcapsules, generally three types.The three types of microcapsules are exposed to blue wavelength light and cured. microcapsules (Y capsules) containing a photocurable material that hardens when exposed to green wavelength light and a dye that produces a magenta color (M
(2) A microcapsule (C capsule) containing a photocurable material that hardens when exposed to red wavelength light and a dye that develops a cyan color. When a photosensitive sheet coated with these three types of microcapsules uniformly dispersed is exposed to, for example, reflected light from a full-color photograph, each microcapsule is partially cured by light of a wavelength to which it is sensitive.

Thereafter, when this photosensitive sheet is pressed, only the uncured microcapsules are destroyed and an image is formed by the dye flowing out.

By the way, each of the microcapsules has different sensitivity characteristics to light due to the difference in the photocurable material. Therefore, even if each microcapsule (for example, is irradiated with the same amount of light), the degree of curing of the microcapsules differs, resulting in the problem that when an image is formed, the color of the image is not faithfully reproduced. In order to prevent this, conventionally, a color correction filter was installed in the optical path of the exposure light of the photosensitive sheet to correct the light intensity.In other words, it cut out specific wavelength light (wavelength light for microcapsules with very high photosensitivity). A filter was provided so that the light sensitivity of the three types of microcapsules appeared to be uniform.

(C1 Problem to be solved by the invention) However, when the optical sensitivity is made to appear uniform by a filter placed in the optical path as in the past, the filter does not only affect the specific wavelength but also the overall light sensitivity. There was a problem that the amount of light decreased. Photosensitive sheets generally had low photosensitivity, and the reduction in the amount of light caused by the filter was not desirable.

An object of the present invention is to provide an image forming apparatus that can correct the sensitivity characteristics of a photosensitive sheet without causing a decrease in the amount of light.

(Means for Solving Problem d1) This invention makes the photosensitive sheet coated with a plurality of types of microcapsules, each sensitive to light of different wavelengths, by irradiating the photosensitive sheet with mixed light of each wavelength. an image forming apparatus comprising: means for inputting sensitivity information of a photosensitive sheet corresponding to the plurality of types of microcapsules or temperature information corresponding to the sensitivity information; The invention is characterized in that it is provided with means for controlling the sheet temperature of the sheet.

(e) Function The photosensitive material (photocurable material) of the microcapsules generally uses a resin that polymerizes at a specific wavelength. This polymerization reaction state is the sensitivity of the microcapsule. The polymerization reaction state of such resins is also affected by heat, and the degree to which they are affected by heat differs depending on the type. Therefore, for example, if microcapsules that have lower sensitivity than other microcapsules at room temperature but whose sensitivity increases when heated are coated on the same photosensitive sheet h as the other microcapsules, the temperature of the photosensitive sheet will be increased to some extent. By doing so, the actual sensitivity of the microcapsules, which have low sensitivity at room temperature, can be corrected and the sensitivity of all the microcapsules on the photosensitive sheet can be made almost uniform.

The present invention takes advantage of this fact, and the temperature of the photosensitive sheet during exposure is controlled in accordance with the sensitivity characteristics of the photosensitive sheet, which is a combination of the sensitivities of the respective microcapsules coated on the photosensitive sheet. The sensitivity characteristics of the photosensitive sheet or the temperature characteristics corresponding to the sensitivity characteristics are input by "a means for inputting sensitivity information or temperature information corresponding to the sensitivity information", and the temperature of the photosensitive sheet is controlled based on the input. Note that the "means for inputting sensitivity information or temperature information corresponding to the sensitivity information" includes a method of reading information written in advance on a photosensitive sheet using an optical sensor or the like within the image forming apparatus, operation keys, and a dip switch.

There is a method of inputting in thousands, etc.

A photosensitive material encapsulated in microcapsules is disclosed, for example, in Japanese Patent Application Laid-open No. 30537/1983.

Embodiment FIG. 5 is a schematic front view of a copying machine which is an embodiment of the present invention.

A document mounting table 2 is provided on the upper surface of the copying machine main body 1, and an optical device 3 including a light source, four reflecting mirrors, and a lens is provided below the document mounting table 2. The original is scanned by moving this optical device 3 in the direction of the arrow in the figure. Two paper feed cassettes 4 are attached to the right side of the copying machine main body 1. This feeding cassette 4 stores cut sheet-like image receiving sheets 41 of different sizes. A paper feeding device 42 disposed at the front E side of the paper feeding cassette 4 feeds image receiving sheets 41 one by one from the selected paper feeding cassette.

A pair of pressure rollers 5 are provided approximately at the center of the copying machine body. This pressure roller can be pressurized/released by a pressure mechanism (not shown) including a spring and an eccentric cam. The pressure on the pressure roller 5 is released during autoloading, which will be described later. The media cartridge 6 is installed slightly to the left of the copying machine main body. Cartridge body 6
1 is equipped with a supply shaft 621 and a take-up shaft 63, and an unused photosensitive sheet 7 is wound around the supply shaft 62. The photosensitive sheet 7 is pulled out from the supply shaft 62, passed through the exposure table 8 and the pressure roller 5, and then wound onto the winding shaft 63.

The light reflected from the original is guided to the position of the exposure table 8 by the optical device 3 described above. As a result, the photosensitive sheet 7 is exposed to light, and the microcapsules exposed to the light are cured according to their sensitivity. A panel heater 81 is provided on the back side of the exposure table 8. The panel heater 81 heats the photosensitive sheet 7 via the exposure table 8 . Note that Sl is a sensor that detects the temperature of the photosensitive sheet (exposure stage).

The photosensitive sheet 7, which has been exposed to light at the exposure table 8 and partially hardened with microcapsules, is overlapped with the image receiving sheet 41 at the pressure roller 5 and is pressed. This destroys the unhardened microcapsules,
The encapsulated dye flows onto the image receiving sheet 41 to form an image. After passing through the glossing device 9, this image receiving sheet 1-41 is discharged to a paper discharge tray 10 on the left side of the main body I of the copying machine.

Meanwhile, the used photosensitive sheet 7 is wound up on the winding shaft 63.

When all the photosensitive sheets 7 on the supply shaft 62 are used up, the photosensitive sheets are replaced together with the cartridge main body 61. That is, the used cartridge body is removed from the copying machine body 1 and a new cartridge body is installed. In this new cartridge body, a leader sheet is provided at the leading end of the photosensitive sheet. The leader sheet is made of a light-shielding, rigid sheet (polyethylene terephthalate sheet, aluminum sheet, etc.), and is automatically fed by the rotation of the conveyance roller when the cartridge main body 61 is installed in the copying machine main body 1. , exposure table8. It is sent to the winding shaft 63 via the Fi-corolla 5 and the like (auto loading). This leader sheet covers the outer periphery of the photosensitive sheet 7, which is in a roll, when the media cartridge is stored unused, thereby shielding the photosensitive sheet from external light. When the photosensitive sheet is attached to the main body of the copying machine, the photosensitive sheet is fed out and automatically cented as described above.

A temperature information mark 71 as shown in FIG. 4 is written on the back surface of the leading end of the leader sheet (the side on which the microcapsules are not coated). The temperature information mark 71 is written between the reference position signal marks 72 and 73. On the other hand, there are marks 71 to 7 in the photosensitive sheet transport path of the copying machine main body I.
A reading device 82 for reading the mark 3 is provided and reads the mark when the leader sheet is conveyed, that is, when the photosensitive sheet 7 is set in the copying machine main body 1.

Figure 3 is a block diagram of the control unit of the copier.
ROM52, RA, and M53 are connected to t.

A cover switch 55 is connected to the CPU 51 via l1054.
．． Mark reading device 82. Inputs are made from the sensor Sl, the operation unit 57, and the like. The cover switch 55 is a sensor that detects opening/closing of the front cover of the copying machine main body 1, and is turned on when the cover is closed after replacing the media cartridge, for example. The temperature information of the photosensitive sort read by the mark reading device 82 is stored in the buffer absorbing memory M. The heater drive circuit 56 is controlled to a predetermined temperature based on this temperature information and the detected value of the sensor S1, and the photosensitive sheet is heated. The operation section 57 has a key for copying conditions.
and a display panel for copying conditions.

Here, the relationship between the sensitivity of the photosensitive sheet and temperature will be explained. FIG. 2 is a diagram showing an example of the relationship between the amount of light required to cure a certain amount of microcapsules and the temperature of the photosensitive sheet. In the example, in order to simplify the explanation, only two capsules, C capsule and M capsule, were explained. The relationship between microcapsules and photosensitive sheet temperature varies depending on the type of photocurable material, and in the case of C capsules encapsulating a certain photosensitive material,
It has good sensitivity at low temperatures (it cures with a small amount of light), but as the temperature rises, the sensitivity decreases. In the case of an M capsule containing another photosensitive material, the sensitivity is very low at low temperatures, but the sensitivity increases as the temperature increases. Therefore, in order to obtain an image with less color unevenness, it is sufficient to set the temperature to a point where the sensitivities of both capsules match, which is point P in the figure.

However, the sensitivity of microcapsules varies depending on the manufacturing loft. This is thought to be due to the influence of oxygen, etc. in the microcapsules. For example, as shown in the figure, in the case of lot "A", the sensitivities of C capsule and M capsule are the same at 42°C, 4), At around 25°C, M capsule has much lower sensitivity (C capsule-3
1M capsule-10). On the other hand, in lot "B", the sensitivities of both capsules were the same at approximately 27°C. Therefore, in order to prevent color unevenness in the formed image, it is desirable to perform exposure at a temperature of the photosensitive sheet of approximately 42°C in the case of A"-7, and in the case of "°B゛° lower). It is desirable to perform the exposure process at about 27°C. This is temperature information and is marked on the leader sheet (Fig. 4, 71).

The temperature of the photosensitive sheet during exposure is controlled within the range of approximately 0 to 100°C, preferably 20 to 50°C, depending on the type and lot.

FIG. 1 is a flowchart showing the main processing procedure of the copying machine.

When the media cartridge 6 is replaced and the front cover is closed, a display indicating the start of processing is displayed on the display panel of the operation section on the top of the copying machine main body (nl-n2→n3). Subsequently, the conveying roller rotates for a predetermined time T to perform autoloading, and the leading edge of the photosensitive sheet 7 is wound and set around the winding shaft 63 (n4, n7→n8). During this autoloading, the mark reading device 82 disposed in the conveyance path of the photosensitive sheet 7 is turned on, and the temperature information written on the leader sheet is read and stored in the backup memory M of the RAM (n5 →n6). After the autoloading is completed, the temperature of the panel heater 81 is controlled based on the newly stored temperature information (n9).

In this embodiment, temperature information is directly input, but sensitivity information may also be input and converted into temperature data within the copying machine main body. Furthermore, operation keys, dip switches, etc. may be used as means for inputting such information.

(g1 Effects of the Invention As described above, in this invention, the temperature of the photosensitive sheet is controlled by input temperature information or sensitivity information, and thereby the sensitivity of the photosensitive sheet can be corrected. Therefore, correction is made in the optical path of the exposure light. There is no need to provide a filter for this purpose, and a decrease in the amount of exposure light can be prevented.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the main processing procedure of a copying machine equipped with a photosensitive sheet heating device, and FIG. 2 is a diagram showing an example of the relationship between the exposure amount and temperature required to harden a certain amount of microcapsules. Figure 3 is a program diagram of the control section of the copying machine.
FIG. 4 is a diagram showing an example of marking of temperature information, and FIG. 5 is a schematic front view of the copying machine. 7-photosensitive sheet, 8-exposure stage, 71-temperature information mark,
81-Panel heater, 82-Mark reading device, Sl
-Temperature sensor.

Claims (1)

[Claims] (1) In an image forming apparatus that sensitizes a photosensitive sheet coated with a plurality of types of microcapsules, each of which is sensitive to light of different wavelengths, by irradiating the photosensitive sheet with mixed light of each wavelength, A means for inputting sensitivity information of a photosensitive sheet according to the microcapsules or temperature information corresponding to the sensitivity information, and a means for controlling sheet temperature during exposure of the photosensitive sheet based on the inputted sensitivity information or temperature information are provided. A full-color image forming device characterized by: