JPH0259749A - Pressure-developing device - Google Patents

Abstract

PURPOSE:To destroy micro-capsules with a simple mechanism by providing vibrator which vibrate press rollers to the bearing sections of the press rollers and applying shearing force to uncured micro-capsules. CONSTITUTION:An upper and lower press rollers 21 and 22 are respectively supported by an upper roller holder (bearing section) 21a and lower roller holder (bearing section) 22a in rotatable states and vibrator 25 using magnetostrictive vibrators 25a are provided to the upper roller holder 21a at locking section 24 (opposite sides to hinges 23) on both ends of the upper and lower roller holders. When the upper and lower press rollers 21 and 22 are rotated while the vibrators 25 are vibrated, the upper press roller 21 is vibrated by the vibration of the vibrator 25 and the vibration is applied to micro-capsules on a media sheet as shearing force. Therefore, uncured micro-capsules can be destroyed easily with such a simple mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION (Al Industrial Field of Application) This invention relates to an image forming apparatus that forms an image using a media sheet coated with photosensitive microcapsules. This invention relates to improvements in pressure developing devices.

(bl Prior Art) In recent years, development of image forming apparatuses that form images using a media sheet coated with photosensitive microcapsules and an image receiving sheet coated with a developing material has been progressing. A photocurable material that hardens when exposed to direct light and a colorless dye are enclosed, and when the media sheet is irradiated with reflected light from the original, the photocurable material partially hardens the microcapsules, creating a selectively cured image (latent image) as a whole. is formed. When the image-receiving sheet is superimposed on this media sheet and pressure is applied, the uncured microcapsules are destroyed and the colorless dye encapsulated in them flows out. This colorless dye is absorbed by the developing material of the image-receiving sheet. Because of the color development, a colored image corresponding to the original image is formed on the image receiving sheet.

The microcapsules have a resin shell with a particle size of about 5 μm and a photocurable material or a colorless dye encapsulated therein. In order to destroy such small microcapsules,
It is necessary to apply a high pressure of about 0 kg/cm, which makes the pressure roller pressure contact mechanism complicated and large, and it is difficult to apply uniform pressure in the axial direction of the pressure roller. There is a problem in that the roller and its bearing must be made of a material that can withstand high pressure, resulting in high costs.

Therefore, as shown in Japanese Utility Model Application No. 62-156955, a piezoelectric member is provided on the surface of at least one of the upper and lower pressure rollers via a contact member, and this piezoelectric member expands and contracts in the direction in which the pressure roller applies pressure. By increasing the pressure applied to the microcapsules, the above-mentioned problem was solved (C1 Problem to be solved by the invention) However, when a piezoelectric member is provided on the surface of a rotating pressure roller, contact between the Even if the parts are arranged, friction between the pressure roller and the pressure roller cannot be avoided, which may cause scratches on the pressure roller surface or stain the pressure roller surface. When scratches occur, problems arise in that the rotation of the roller becomes distorted and the pressure roller does not come into uniform contact with the microcapsules, making it impossible to perform sufficient development.

In addition, microcapsules are made by enclosing liquid colorless dye, etc. in a resin shell, and the particle size is small, about 5 μm, so it is strong against compressive force, and the microcapsules are destroyed by vibration in the direction of pressure. In order to do this, it was necessary to apply a considerable amount of vibration.This invention was developed in view of these problems.
The object of the present invention is to provide a pressure developing device that can destroy microcapsules with a simple mechanism.

(d) Means for Solving the Problems This invention involves exposing a media sheet coated with microcapsules containing a colorless dye to image information light to form a latent image, and then applying pressure to the sheet using a pressure roller. In a pressure developing device that destroys uncured microcapsules by applying pressure and forms a colored image with the colorless dye that flows out, one of the pressure rollers (both of which have a vibrating body disposed in one bearing part to vibrate the pressure roller) is used. It is characterized by

(e) Effect As mentioned above, uncured microcapsules are relatively strong against compressive force, but weak against shear force and easily destroyed.

In this invention, a vibrating body is provided on the bearing portion of the pressure roller, and the pressure roller is rotated while the vibrating body vibrates. Therefore, the vibration of the vibrating body is transmitted from the bearing to the main body of the pressure roller, and the rotational force of the pressure roller is added to the vibration force, causing shearing force to be applied to the microcapsules on the media sheet, causing the destruction of the microcapsules. becomes easier.

(f) Embodiment FIG. 5 is a schematic front view of a copying machine equipped with a pressure developing device according to an embodiment of the present invention.

A media cartridge 1 is provided approximately in the center of the main body of the copying machine. Media cartridge 1 is supply shaft 11
It is equipped with three take-up shafts 12, and an unused media sheet is wound around the supply shaft 11.

A pressure developing device 2 is provided on the right side of the media cartridge 1, and the media sheet on the supply shaft 11 is wound onto a take-up shaft 12 via the exposure section PL and the pressure developing device 2.

A document table 31 is provided on the top surface of the copying machine main body, and a document to be copied is placed thereon. A light source 3 is provided at the bottom of this document table 31.
2. An optical system having mirrors 33 to 36 and a lens 37 is arranged, and scans the original placed on the original platen 31 and guides the reflected light to the exposure section P1 (therefore, the media sheet is not exposed at the exposure section P1). The document is exposed to reflected light, and the microcapsules are partially cured to form a selectively cured image.

A paper feed section including a paper feeder (41, 42) is provided on the right side of the copying machine main body. Image receiving sheets are stored in the paper cassettes 41, 42 with the developing material side facing upward, and the image receiving sheets are fed from either of the paper cassettes 41, 42. The image-receiving sheet fed from the paper cassette 41 (42) comes into contact with the PS roller 43 and stops once, and the PS roller 43 rotates at the timing when it is defeated by the selectively hardened image of the media sheet, thereby forming a pressure developing device. 2
Paper is fed to Further, a paper detection sensor 44 is provided at the PS roller 43 position. The paper detection sensor 44 is made of, for example, a microsinch, and is turned on in the presence of an image-receiving sheet. Therefore, when the image receiving sheet completely passes the position of the PS roller 43, the paper detection sensor 44 is turned off.

The image receiving sheet is superimposed on the selectively cured image of the media sheet in the pressure developing device 2 and is pressed. This destroys the uncured microcapsules of the media sheet, and the encapsulated colorless dye flows out and is colored by the developing material of the image-receiving sheet, forming a colored image. The image receiving sheet on which the colored image has been formed is separated from the media sheet, conveyed to the left in the figure, and heated by the heating device 5. This heating accelerates the coloring reaction of the colorless dye, and if the image-receiving sheet is coated with a thermoplastic resin, the heating softens or melts the thermoplastic resin and coats the surface of the colored image. Gives shine to. After heating, the image receiving sheet is discharged onto a paper discharge tray 6. In addition,
The media sheet from which the image-receiving sheet has been separated in the pressure developing device 2 is wound onto a winding shaft 12.

FIG. 1 is an external perspective view of the pressure developing device 2, and FIG. 2 is a side configuration diagram thereof.

The pressure developing device 2 includes an upper pressure roller 21 and a lower pressure roller 22.
The upper pressure roller 21 has an upper roller holder (bearing part).
21a, the lower pressure roller 22 is rotatably supported by a lower roller holder (bearing portion) 22a. The media sheet on which the selectively cured image is formed and the image receiving sheet superimposed on the selectively cured image are moved by upper and lower pressure rollers 21.
, 22, the uncured microcapsules are destroyed, the colorless dye flows out, and a colored image is formed on the image receiving sheet. The upper roller holder 21a is rotatably supported by a hinge 23 with respect to the lower roller holder 22a, and is engaged with the lower roller holder 22a on the opposite side of the hinge 23, so that the upper pressure roller 21 is connected to the lower pressure roller 22. is pressed with a certain amount of force. Upper roller holder 21a and lower roller holder 22a retaining portion (hinge 2
The vibrating body 25 is attached to the upper roller holder 21a of 24 (on the opposite side of 3).
is installed.

As the vibrating body 25, for example, one using a magnetostrictive vibrator 25a is used. Since the magnetostrictive vibrator 25a has a small amplitude and is insufficient to vibrate the upper pressure roller as it is, the amplitude is expanded using the horn 25b. When the upper and lower pressure rollers 21 and 22 are rotated while vibrating the vibrating body 25, the vibration of the vibrating body 25 is transmitted to the upper pressure roller 21 via the upper roller holder 21a, and the upper pressure roller 21 vibrates. This vibration acts as a shearing stress on the microcapsules of the media sheet, thereby easily destroying the uncured microcapsules.

By providing the vibrating body 25 on the retaining portion 24 on the opposite side of the hinge 23, the vibration of the vibrating body 25 is efficiently transmitted to the upper pressure roller 21 by the lever principle. are provided at both ends of the pressure roller, so that vibrations transmitted to the upper pressure roller 21 will not be uneven.

By providing the vibrating body 25 in the engaging portion 24 as described above, uncured microcapsules can be easily destroyed with a small pressing force and little vibration. Here, regarding the timing of operating the vibrating body 25, there are two possible timings for operating the vibrating body 25. One is the method of operating the above when the upper and lower pressure rollers 21 and 22 rotate, and the other is ■The image receiving sheet is placed on the upper and lower pressure rollers 21 and 2.
This method is activated when passing between the two.

In terms of efficiency, method (2) is preferable, and method (2) is applied in this embodiment.

FIG. 4 is a block diagram of the pressure developing device.

In the figure, reference numeral 61 denotes a control unit that controls the entire copying machine, and receives input from each sensor such as the paper detection sensor 44 and each key such as a print switch. These inputs and Ps roller 430 control status (when PS roller starts rotating)
Accordingly, the control unit 61 controls the vibrating bodies 25 and 25 using the controller 62.

FIG. 3 is a flowchart 1 showing the processing procedure of the pressure developing device.

When the copying process is started, the rotational state of the PS roller 43 is determined at nl. Note that the upper and lower pressure rollers 21 and 22 start rotating at the start of the copying process. PS roller 43
As mentioned above, since the image receiving sheet rotates at the timing when it is overlapped with the selectively cured image on the media sheet, the PS
The rotation of the roller 43 represents the feeding of the image receiving sheet. P
When the S roller 43 starts rotating, a timer t is started at B2, and when the timer t reaches the measured time TI (B3), the vibrating body 25 is activated (B4). Note that the measured time T1 is P
This is the time it takes for the leading edge of the image receiving sheet that has passed through the S roller 43 to reach between the upper and lower pressure rollers 21 and 22. As a result, when the leading edge of the image-receiving sheet reaches between the upper and lower pressure rollers 21 and 22, the vibrator 25 is activated, and shearing stress is applied to the uncured microcapsules, causing them to break and form a colored image.

Then, when the image receiving sheet completely passes the PS roller 43 position (when the paper detection sensor 44 is turned off)
(B5) The timer t is started (B6), and when the timer t reaches the measured time T2 (B7), the vibrating body 25 is stopped. The timer T2 is a time period until the rear end of the image receiving sheet that has passed the position of the paper detection sensor 44 finishes passing between the upper and lower pressure rollers 2m22. Therefore, the vibrating body 25 stops when the pressure development process (formation of a colored image) is completely completed.

Further, FIG. 6 shows another embodiment showing the processing procedure of the pressure developing device, in which the paper cassette 41. A paper size detection sensor (not shown) provided at 12 detects the size of the image-receiving sheet to be fed, and controls the vibrating body 25 accordingly.When the copying process starts, the image-receiving sheet first The size of the image receiving sheet is determined (nil, n12), and the measured time T4 is set according to the size of the image receiving sheet.

This time measurement is the time from when the leading edge of the image receiving sheet passes the PS roller (after the PS roller starts rotating) until the rear end of the image receiving sheet finishes passing between the upper and lower pressure rollers 21 and 22. Since the time varies depending on the size of the image receiving sheet, it is set according to the size of the image receiving sheet. In this embodiment, the setting time is set to A4, which is frequently used. Each size of B5 and 3 of other sizes
Although the method is set for each type, the method may be used for other types.

When the rotation of the PS roller 43 is started at ri 16, a timer t is started (n17), and when this reaches T3 (n18), the vibrating body 25 is activated (n19). Note that T3 is the same time as T1 shown in Figure 3, that is, P
This is the time it takes for the leading edge of the image receiving sheet that has passed the S roller 43 to reach between the upper and lower pressure rollers 21 and 22. In this way, the vibrating body 25 starts vibrating, the uncured microcapsules are destroyed, and a colored image is formed on the image receiving sheet. Then, when T4 set by timer t711<nL3 to n15 is reached, that is, when the rear end of the image receiving sheet passes between the upper and lower pressure rollers 21 and 22, the vibrating body 25 stops and the pressure development process ends. do.

As described above, the image receiving sheet is transferred to the upper and lower pressure rollers 21.2.
The vibrating body 25 can be actuated only when the vibrating body 25 passes between the two, thereby eliminating waste of electric power for operating the vibrating body.

In this embodiment, a magnetostrictive element is used as the vibrating body, but other elements that vibrate the pressure roller, such as a piezoelectric element, may also be used, and the installation location is in the holder of the lower pressure roller, or in the upper and lower positions. Pressure rollers may be provided on both holders.

+g+ Effects of the Invention As described above, according to the present invention, by providing the vibrating body in the bearing portion of the pressure roller, shear stress can be applied to the microcapsules by the rotation of the pressure roller and the vibration of the vibrating body. It is easy to break the hardened microcapsules (because it becomes easy to destroy), there is no need for a complicated pressure welding mechanism to apply excessive pressure to the pressure low-y or expensive materials to construct it, and the advantage is that the cost can be reduced. In addition, by providing the vibrating body in the bearing part, there is no contact with the pressure roller itself, and it is possible to prevent the pressure roller from being distorted or damaged.

1a-upper roller holder; 2-lower pressure roller; 2a-lower roller holder; 3-hinge, 4-(Upper and lower roller holder) 5- Vibrating body.

engaging part,

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of a pressure roller section of a pressure developing device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional configuration diagram thereof.
FIG. 3 is a flowchart showing the processing procedure of the pressure developing device, FIG. 4 is a block diagram of the same pressure developing device, and FIG. 5 is a schematic front view of a copying machine using the same pressure developing device. FIG. 6 is a flowchart showing another embodiment of the processing procedure of the pressure developing device.

Claims (1)

[Claims] (1) A media sheet coated with microcapsules containing a colorless dye is exposed to image information light to form a latent image, and then the uncured microcapsules are destroyed by applying pressure to the media sheet with a pressure roller. What is claimed is: 1. A pressure developing device for forming a colored image using a colorless dye that flows out of the pressure roller, the pressure developing device comprising: a vibrator for vibrating the pressure roller;