JPH0498257A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of wrinkle in a recording sheet and, in addition, to improve recording in quality and correction by coating only an image formation area with a developer, and also developing only the coated area by means of pressure-contact. CONSTITUTION:After an original 9 is placed on an original platen 9, a halogen lamp 5 is turned on, and the latent image of the original 9 is formed on a microcapsule sheet 11, which travels between the sheet feeding roll 13 and the winding roll 15, by means of exposure. The sheet 11 subjected to the exposure by an exposure device 1 is supplied into a pressure-development device 3. On the other hand, a sheet of plain paper P is inserted into a powder application device 2 by a guide roller 21, and is carried to an application area 43 by a carrying belt 35. An area corresponding the latent image of the original 9 is coated with the developer S, and the sheet of plain paper P is supplied to the device 3 as a developed sheet K. In the device 3, the sheets 11 and K are superimposed and only the part where the latent image is formed is selectively developed by means of pressure, so that a color image is recorded on the sheet K. Subsequently, the sheet K is carried to a thermal fixing device 4 to be heated. Thus, the recorded image is fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for forming an image by bringing a photosensitive recording medium on which a latent image has been formed into contact with a recording sheet coated with a color developer under pressure.

[Prior Art] Conventionally, as an image forming apparatus, one that performs pressure development by bringing a microcapsule paper and a recording sheet into close contact with each other is known.

This involves exposing microcapsule paper, which carries microcapsules on its surface that contain dye precursors, photopolymerization initiators, etc. and whose mechanical strength changes in response to light, through an original, and after the exposure, the microcapsules are exposed to light. The paper and a recording sheet (developer paper), which has granular color developer adhered to the surface of a support such as plain paper using a color developer applicator, are sent into a pressure developing device and brought into close contact with each other, and the mechanical strength is increased by the exposure described above. The microcapsules in which the color has been reduced are destroyed by pressure, and the dye precursor inside them is flowed out, and the developed color image is transferred onto the color developer paper by reacting the flowed out dye precursor with the color developer. After pressure development, the developer paper is sent to a heat fixing device to fix the color image on the developer paper.

=2- The color developer used in such an image forming apparatus may cause the print to smear or the ink to be repelled when an attempt is made to print on the color developer paper after image formation using a laser printer, typewriter, etc. This degrades print quality. For this reason, a technique has been developed in which a color developer is applied only to the area where an image is to be formed (see Utility Model Application No. 1-94828).

[Problems to be Solved by the Invention] However, in conventional image forming apparatuses, the thickness of the area coated with the color developer and the area not coated with the color developer on the recording sheet is different. If the sheet and microcapsule paper are overlapped and subjected to pressure development as they are, pressure spots will occur between areas to which the color developer has been applied and areas to which it has not been applied. For this reason, feeding unevenness may occur on the recording sheet, causing wrinkles, or pressure unevenness may occur, resulting in uneven color density. In addition, the areas of the recording sheet to which the color developer is not applied are also excessively smoothed due to the pressure phenomenon, making it difficult to write characters with a pencil or the like on these areas.The present invention solves the above problems. An object of the present invention is to provide an image forming apparatus that does not cause wrinkles or color density unevenness on a recording sheet, and improves the ease of writing on the recording sheet.

[Means for Solving the Problems] As a means for achieving the above object, the image forming apparatus of the present invention, as illustrated in FIG. and a recording sheet coated with a color developer that develops color when pressed into contact with a portion of the photosensitive recording medium on which a latent image is formed, and forming an image on the recording sheet, the image forming apparatus comprising: A color developer applying means for applying a color developer to an image forming area corresponding to the latent image and a contact area corresponding to the latent image or the image forming area bring the photosensitive recording medium and the recording sheet into pressure contact. The gist is to include a contact developing means.

[Function] In the image forming apparatus of the present invention, a latent image is first formed on a photosensitive recording medium, and a color developer is applied to the image forming area of the recording sheet corresponding to the latent image. Next, a contact developing means brings the photosensitive recording medium and the recording sheet into pressure contact in a contact area corresponding to the latent image or the image forming area.

Therefore, the image forming area to which the color developer is applied becomes the contact area between the photosensitive recording medium and the recording sheet, and is actually pressed into contact with the recording sheet. Therefore, areas other than the contact area are not touched. Moreover, for example, the recording sheet is uniformly fed and the contact areas are developed with uniform pressure.

[Example] Next, an example of the image forming apparatus of the present invention will be described. Second
The figure is a configuration diagram of a color image recording apparatus M according to an embodiment.

The color image recording apparatus M includes an exposure device], a powder coating device 2, a pressure developing device 3, and a heat fixing device 4. Powder coating device 2, pressure developing device 3, and heat fixing device 4
is housed in casing C. The exposure device 1 is
The upper opening of the casing C is provided.

Exposure device] includes a halogen lamp 5 and a document table 7. A document table 7 places a document 9 thereon.

The halogen lamp 5 exposes the microcapsule paper]] (light-sensitive and pressure-sensitive paper) to transfer the latent image of the document 9 to the microcapsule 1.
1. Microcapsule paper] is supplied from a paper feed roll [3] and is wound up on a bill take-up roll [5]. The paper feed roll 13 and the take-up roll 15 are arranged inside the casing C. The microcapsule paper] is guided by a plurality of guide rollers 17 as shown in the figure, and passes through an exposure device] and a pressure developing device 3 in the order of sheets.

The powder coating device 2 is disposed approximately at the center of the casing C. A paper feed cassette 19 is located near the powder coating device 2.
is installed. The paper feed cassette 19 stores plain paper P. The plain paper P is taken out from the paper feed cassette 19 and guided to the tag guide roller 21 and fed into the powder coating device 2 through the tongue insertion opening 23 .

The powder coating device 2 includes a developer storage tank 25, a developer carrying roller 27, a developer supply roller 29, a counter electrode roller 31, and a guide roller 33a.

33b, a conveyor belt 35, a DC power supply 37, a plurality of electrodes 39, and a control section 41.

The color developer storage tank 25 stores granular color developer S.

The color developer carrying roller 27 carries the color developer S by rotating.
is supported and sent to the attachment area 43. The developer supply roller 29 comes into contact with the developer carrying roller 27 and assists the developer carrying roller 27 in carrying the developer S. The counter electrode roller 31 is arranged to face the developer carrying roller 27 with a gap d in between. Counter electrode roller 3]
has a thin surface made of an insulator. The conveyor belt 35 includes a counter electrode roller 31 and a guide roller 33a.
, 33b and the hook are passed, and the plain paper P is conveyed. The DC power supply 37 applies voltage to the plurality of electrodes 39 .

As shown in FIGS. 2 and 3, the plurality of electrodes 39 are
With respect to the surface of the counter electrode roller 3 , a plurality of electrodes are arranged in parallel opposite to the adhesion region 43 1 , that is, along the inner back surface of the counter electrode roller 31 . A sensor 45 is arranged near the counter electrode roller 31. The sensor 45 detects the position and conveyance speed of the plain paper P. As shown in FIG. 4, the control unit 41 includes a correction circuit 51 and an A/D data processing circuit 52.
, a sensor control and other pulse circuit 53 , a motor drive circuit 54 , and an electrode drive circuit 56 .

A reading device 81 is connected to the correction circuit 5].

The sensor 45 and a pulse generator 83 with one line period are connected to the sensor control and other pulse circuit 53. The motor drive circuit 54 is connected to a motor 61 that is disposed in the powder coating device 2 and drives each part. A DC power supply 37 and an electrode 39 are connected to the electrode drive circuit 56 .

The reading device 8] is disposed in the exposure device 1 and includes a light emitting source made of, for example, a light emitting diode that emits light, a rod-shaped lens made of, for example, a Selfoc lens that focuses an image on the document onto a light receiving element, and a document. CdS that receives the image above
, CdSe, and 5e-As-Te, a register that reads one line of the image of the document from a plurality of light-receiving elements, and an amplifier that amplifies the signal read by the register. ] A line-period pulse generator 83 is attached to the reading device 8 and is composed of an encoder and a photointerrupter. The correction circuit 51 corrects the waveform of the signal detected by the reading device 8. The sensor control and other pulse circuit 53 performs the extraction height of the read signal for one line using one pulse signal for one line generated by the pulse generator 83 with one line period. The A/D data processing circuit 52 binarizes or multi-values the signal corrected by the correction circuit 5 and performs calculations. The electrode drive circuit 56 controls the voltage applied to each electrode 39 according to the signal sent from the A/D data processing circuit 52.

With the above-described configuration, the powder coating device 2 has a reading device 8.
] A voltage is applied to a predetermined electrode 39 based on the output signal. As a result, a layer of color developer S having a shape corresponding to the latent image formed on the microcapsule paper 1 is formed on the plain paper P. That is, the color developer S is selectively electrostatically applied only to necessary positions of the image on the original 9.

18= The plain paper P selectively coated with the color developer S by the powder coating device 2 becomes color developer paper and is discharged from the outlet 63 as shown in FIG. This developing paper is conveyed by a guide roller 65 and fed into the pressure developing device 3.

The pressure developing device 3, as shown in FIGS. 2 and 5,
Two lower rollers 71A, 71B (denoted as 71 if there is no need to distinguish), seven upper rollers 73A,
738.73C--73G (denoted as 73 if there is no need to distinguish) and seven piezoelectric elements 75A, 75B
, 75C, . . . , 75G (denoted as 75 if there is no particular need for distinction), and a development control section 77. Each upper roller 73 is provided with a corresponding piezoelectric element 75 . In addition, in FIG. 5, only the piezoelectric element 75G is shown, and illustration of the other piezoelectric elements 75A, 75B, . . . , 75F is omitted.

Each piezoelectric element 75 is connected to the shaft portion 73a of the corresponding upper roller 73 via a pressure spring 79. In other words, when the piezoelectric element 75 is driven toward the center, the upper roller 73 is strongly pressed against the lower roller 71 via the pressure spring 79.

The development control section 77 includes a storage circuit 82 as shown in FIG.
, a drive signal output circuit 84 , a counting circuit 85 , an actuator drive circuit 87 , and a DC power supply 89 . The piezoelectric element 75 is connected to the actuator drive circuit 87 .

The storage circuit 82 temporarily stores the signal output from the A/D data processing circuit 52. The counting circuit 85 counts the pulse signals output from the sensor control and other pulse circuits 53, and when a predetermined number is reached, outputs an actuator drive start signal. When the drive signal output circuit 84 receives the actuator drive start signal, it sequentially reads out the pigs from the storage circuit 82 and outputs them to the actuator drive circuit 87 . Actuator drive circuit 87 drives piezoelectric element 75 in the expansion direction in response to a signal from drive signal output circuit 84 . In other words, the signal output from the A/D data processing circuit 52 is stored in the storage circuit 82, and the developing paper K
is supplied to the pressure developing device 3, the data temporarily stored corresponding to this is used as drive data for the piezoelectric element 75.

With the above-described configuration, when pressure developing the portion where the color developer paper and the microcapsule paper 11 are overlapped, the pressure development device 3 selects only the portion of the color developer paper K coated with the color developer S. Apply pressure to the target.

Next, the operation of this embodiment will be explained. After placing the original 9 on the original table 7, the user presses a start switch (not shown) to start image recording. Then, the halogen lamp 5 lights up, and the paper feed roll 13 and take-up roll 1
A latent image of the document 9 is formed on a part of the microcapsule paper 1 by exposure. The microcapsule paper 1 exposed by the exposure device 1 is supplied into the pressure developing device 3. On the other hand, in the powder coating device 2, when a start switch (not shown) is pressed, the plain paper P is moved to the guide roller 21.
is inserted into the powder coating device 2 by. The inserted plain paper P is conveyed to the attachment area 43 by the conveyor belt 35.

With the plain paper P conveyed to the attachment area 43, the original platen 7
The upper document 9 is read by the reading device 8 shown in FIG. Also, in synchronization with this reading operation, the powder coating device 2
is driven. As a result, the document 9 is placed on a portion of the plain paper P.
A color developer S is applied in a shape corresponding to the latent image. The color developing paper produced by the powder coating device 2 is fed into a pressure developing device 3.

The pressure developing device 3 superimposes the microcapsule paper 11 and the color developer paper, and selectively pressure develops only the portion where the latent image is formed. This records a color image on the developer paper.

After pressure development, the developer paper is conveyed to the heat fixing device 4 by a guide roller 90. A thermal fixing device 4 heats the color developer paper and fixes the recorded image on the color developer paper. The developing paper with the fixed image is conveyed by a guide roller 92 and discharged to the outside of the color image recording apparatus M.

The color image recording apparatus M described above prepares a color developer paper K coated with a color developer S only in the portion on which an image is to be recorded, and presses only the portion coated with the color developer S to perform pressure development. As a result, it becomes color developer paper and microcapsule paper]
In the pressure development performed by overlapping 1 and 1, paper feeding irregularities do not occur, and the development of wrinkles on the color developing paper K is prevented. Furthermore, since the occurrence of pressure development spots is eliminated, the quality of the image is improved. Furthermore, the color developer S is not applied to areas other than the image recording area of the color developer paper K after the image has been recorded, and no strong pressing force is applied thereto. Therefore, the ease of adding to the color developer paper is improved.

As a result, it is possible to provide a color image recording device that improves both the image quality after addition and the quality of the developing paper, which is an extremely excellent effect.

Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented in various forms without changing the gist of the present invention.

For example, the upper roller 7 of the pressure developing device 3 shown in FIG.
3, an upper roller 173 as shown in FIGS. 6 and 7 may be used. The upper roller] 73 is a single roller that performs pressure development, and as shown in FIG.
(If there is no particular need to distinguish, write 175) and
shaft] 77. The split ring 175 is formed by molding an elastic body into a ring shape. Each split ring 175
and the shaft 177, as shown in FIG.
81 is interposed. Four piezoelectric elements 181 are arranged for each split ring 175, and when driven in the stretching direction, only the attached split ring] 75 is expanded. Therefore, by selectively driving the piezoelectric element [8], pressure development can be performed in a specified selection range.

By using these upper rollers 7 and 3, the pressure developing device 3 can be downsized.

In this embodiment, the color developer S was applied to the plain paper P, but instead of this, the color developer S was applied to the microcapsule paper on which the latent image was formed, and this and the color developer S were applied to the plain paper P. It is also possible to perform pressure development by superimposing the two.

In the above embodiment, the document 9 is read by the reading device 81, and based on this data, the range for applying the color developer S and pressure development is automatically determined and executed. In addition, the area in which the color developer S is applied and the pressure development is performed may be arbitrarily designated by the operator's operation on a console (not shown). For example, the area where the color developer S is applied and the pressure development is performed may be limited to a predetermined area such as the center or upper half of the plain paper P.

[Effects of the Invention] The image forming apparatus of the present invention applies a color developer only to the image forming area of a recording sheet, and performs development by bringing only the portion coated with the color developer into pressure contact. (Secondly, during development, only the area coated with the color developer is brought into contact with pressure, so the thickness of the area to be developed becomes uniform. For example, when passing between rollers for pressure contact, , the paper is fed evenly by the rollers.Therefore, wrinkles are less likely to occur on the recording sheet.

Furthermore, since the thickness of the contacting portion becomes uniform, the development state becomes uniform. Therefore, color density unevenness is less likely to occur.

Moreover, since neither the application of a color developer nor development by pressurized contact is performed on areas other than those to be recorded on the recording sheet, the retouchability of the recording sheet is improved.

As a result, it is possible to provide an image forming apparatus that does not cause wrinkles on the recording sheet and has high recording quality and ease of addition, which is an extremely excellent effect.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating the basic structure of an image forming apparatus of the present invention, FIG. 2 is a block diagram of a color image recording apparatus according to an embodiment, FIG. 3 is a block diagram of its powder coating device, and 5 is a block diagram of the control of the image recording apparatus, FIG. 5 is a configuration diagram of the pressure developing device, FIG. 6 is a perspective view of a modified upper roller, and FIG. 7 is an explanatory diagram of its structure. M... Color image recording device S... Color developer K... Color developer paper 2... Powder coating device 4... Heat fixing device 173.73... Upper opening 181.75... Piezoelectric element 77...development control section

Claims (1)

[Claims] 1. A photosensitive recording medium that forms a latent image using light from an irradiated original, and a recording sheet that is coated with a color developer that develops color when it comes into pressure contact with the portion of the photosensitive recording medium on which the latent image is formed. an image forming apparatus for forming an image on the recording sheet, comprising: a color developer applying means for applying a color developer to an image forming area corresponding to the latent image; and a color developer applying means corresponding to the latent image or the image forming area an image forming apparatus comprising: a contact developing means for bringing the photosensitive recording medium and the recording sheet into contact under pressure in a contact area;