JPS6328171A - Image forming device - Google Patents

Abstract

PURPOSE:To extremely simply form a printing original plate forming film by reading an original as plural types of chrominance signals, converting into an image forming signal, using an image forming medium of a single color to successively form images of the same number as the image forming signals of the plural colors on formed picture medium to be formed the image. CONSTITUTION:The original is optically scanned by a scanner 11 to read as three types of chrominance signals of cyan green, yellow and the three types of the chrominance signals are converted into the image forming signals of four colors of yellow, Magenta, cyano, black. The image is formed on a plastic film by the use of a thermal transfer ink ribbon of a single black color by one image forming signal of the image forming signals of the four colors. Thereby, the printing original plate forming film can be extremely simply formed with a comparatively simple constitution without using complicate production processes such as an exposure, a development as the conventional way and a compact and in expensive film can be realized.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to an image forming method for forming an image of a color-separated original document, which is required when creating a printing plate for offset printing, for example. Regarding equipment.

(Prior Art) Recently, plate making and printing technology has made great progress with the development of electronics, and electronic plate making has become mainstream today. This electronic plate making photoelectrically converts the shading of the original image,
By performing certain processing on the electrical signal, the intensity of the light is changed, exposing the film (photosensitive material), and developing it to create negative or positive film, which is the basis of the original printing plate. .

However, in such a method, the manufacturing process is very complicated, and the machine itself is large and therefore very expensive. Furthermore, in the past, it was only possible to create a film for one color at a time.

(Problems to be Solved by the Invention) As mentioned above, in the conventional method of creating a film for printing original plates, the manufacturing process is very complicated, and the machine itself is large, so it is very expensive. The disadvantage is that it is possible to produce only one color of film at a time.

Therefore, the present invention eliminates the above-mentioned drawbacks, and makes it possible to create a film for creating a seal and column original plate very easily without using the complicated production process as in the past. Moreover, it can be realized in a small size and at low cost. An object of the present invention is to provide an image forming apparatus capable of continuously producing a film for producing a printing original plate for each zero at a time.

[Structure of the Invention] (Means and Effects for Solving the Problems) The image forming apparatus of the present invention optically scans a document to read it as a plurality of types of color signals, and converts each obtained color signal into a plurality of color signals. converting the image forming signals into image forming signals of the plural colors, and sequentially forming the same number of images as the image forming signals of the plural colors on the image forming medium using the image forming medium of a single color using the image forming signals of the plural colors. As a result, a film for creating a printing original plate can be created very easily, and moreover, a film for creating a printing original plate for each 0 can be created continuously.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 2 and 3 show, as an example of the image forming apparatus according to the present invention, a thermal transfer color copying machine that is capable of selectively producing multicolor color copies and producing films for producing printing original plates. That is, 1 is a main body of a copying machine, and an operation panel 2 is provided at the front of the upper surface of the main body 1. The left side of the main body 1 is a document scanning section 8 that scans and reads a document set on a document table 7, and the right side is an image forming section. Note that 10 is a document cover provided on the document table 7 so as to be openable and closable.

The document scanning section 8 is configured as shown in FIGS. 4 and 5, for example. That is, the document table 7 is fixed to the main body 1, and the document O set on the document table 7 is placed below the document table 7 by reciprocating along the lower surface thereof in the direction of arrow a in the figure. A scanner 11 is provided for optical scanning and reading. The scanner 11 includes an illumination lamp 12 that illuminates the original NO, a photoelectric converter 13 that receives reflected light from the original O, and guides the reflected light from the original O to the photoelectric converter 13 (an optical system 14 and supports these). Carriage 15
Consisted of. The photoelectric converter 13 separates and outputs the image of the original O as color signals of cyan, green, and yellow (or red, green, and blue) light by charging and converting the reflected light from the original 0, for example. It is mainly composed of a CCDCD beline image sensor. As shown in FIG. 5, the carriage 15 is guided by a guide rail 16 and a guide shaft 17 so as to be able to reciprocate in the direction of arrow a. At one end of the guide shaft 17, a scanning motor (for example, a pulse motor) 18 capable of forward and reverse rotation is mounted.
A drive pulley 19 is driven by a drive pulley 19, and a driven pulley 20 is disposed at the other end of the drive pulley 19.
A timing belt 21 is stretched between 9° and 20°. One point of the timing belt 21 is fixed to the carriage 15 via a fixing member 22.

This allows the carriage 15 to move linearly by rotating the scanning motor 18 in the forward or reverse direction.

The image forming section 9 is configured as shown in FIG. 6, for example. That is, a platen 30 is disposed approximately at the center of the image forming section 9, and a thermal head 31 is disposed on the left side facing the platen 3o. The thermal head 31 is attached to a heat radiator 33 that is integrally formed on the rear end surface of the holder 32.

A ribbon cassette 35 containing a thermal transfer ink ribbon 34 as an image forming medium is detachably attached via a holder 32, and the thermal transfer ink ribbon 34 is interposed between the thermal head 31 and the platen 3o. It has become. As shown in FIG. 6, the ribbon cassette 35 has two parallel winding cores 36 and 37 around which both ends of the thermal transfer ink ribbon 34 are wound, and a midway portion of the thermal transfer ink ribbon 34 is wound around the cores 36 and 37. In order to be interposed between the platen 30 and the thermal head 31, it is covered with a case 38 with a part thereof exposed. When the ribbon cassette 35 is attached, the winding cores 36 and 37 are connected to a drive shaft of a motor (not shown) via a drive force transmission mechanism (not shown), and are rotated as necessary. Further, as shown in FIG. 2, the ribbon cassette 35 can be inserted into or removed from the holder 32 through an insertion/removal port 39 formed on the right side of the main body 1. Note that the insertion/removal port 39 is provided with a lid 40 that can be opened and closed.

A paper feed roller 41 is provided at the diagonally lower right portion of the platen 3o, and a paper feed roller 41 is provided as an image forming medium (or a plastic film) housed in a paper feed cassette 42.
P is taken out one by one. Paper feed roller 41
The paper P taken out is sent to the registration rollers 43 disposed diagonally above and to the right of the paper feed row 541, and its leading edge is aligned, and then transported by the registration rollers 43 toward the platen 30. The pressing is wrapped around the platen 30 by the rows 544.45, and is thereby accurately fed. Here, the paper feed cassette 42 is detachable from the front of the main body 1.

Note that 46 in FIG. 6 is a manual paper feeding device for manually feeding the faP.

The thermal head 31 presses the paper P against the platen 30 via the thermal transfer ink ribbon 34, and as shown in FIG. It is designed to be transcribed. As shown in FIGS. 7 and 8, the thermal transfer ink ribbon 34 has a width approximately equal to that of the MP and is yellow.

Magenta, cyan, and black ink portions 47Y.

47M, 47C, and 47s are sequentially stacked one on top of the other, and after transferring one color at a time, the paper P is returned to the transfer starting position, and the sheets are accurately stacked one after another. Note that the thermal transfer ink ribbon 34 may not have the black ink portion 47s, and in that case, substantially black can be produced by overlapping the three colors of yellow, magenta, and cyan.

In addition, in the case of color copying, each ink part 47Y, 47M of the thermal transfer ink ribbon 34 is used as described above.

Image formation is performed using 47c and 47a. On the other hand, when producing a printing original plate production film, a solid black thermal transfer ink ribbon, for example, is used as the thermal transfer ink ribbon 34 to form an image. In this case, it is not necessary to use a solid black thermal transfer ink ribbon, and the image may be formed using the black ink portion 47B of the transfer ink ribbon 34.

During color copying, the paper P is reciprocated by the number of colors by the rotation of the platen 30. At this time, the path of the paper MP is to the bottom surface of the paper output tray 48 which is provided on the main body 1 at an angle. The 1st. 2nd information board 49.50
be led upwards. This includes the platen 30 and the first. The first guide plates 49 and 50 are respectively provided between the ends of the second guide plates 49 and 50.
This is done by the second distribution gates 51, 52. That is, first, the MP taken out from the paper feed cassette 42 is transferred through the registration roller 43 and the first S gate 51, and its leading end is wound around the platen 3o. Next, the platen 30 is rotated in the forward direction by a pulse motor (not shown) to transport the MP at a constant speed, and the heating elements of the thermal head 31 arranged in a line tod shape along the axial direction of the platen 3o. (not shown) generates heat in response to the print signal, and thereby the ink 47 of the thermal transfer ink ribbon 34 is transferred onto the paper P. Then, the IIP that passed through the platen 30
At this time, the tip of the second trimming gate 5 is located at the solid line position.
2, the paper is sent onto a first guide plate 49 provided along the lower surface of the paper discharge tray 48. In this way, when the transfer of one layer of ink 47 is completed, the platen 30 is rotated in the opposite direction, so that the paper P is reversely fed and returned to the transfer starting position. At this time, the first
The photographing gate 51 allows the rear end of the paper P to be placed on the first guide plate 4.
9 is sent onto a second guide plate 50 provided along the lower surface of the paper. In this way, a plurality of colors are transferred by moving the paper P back and forth a plurality of times. Finally, the paper P on which all the colors of ink 47 have been transferred is
At this time, the second distribution gate 5 is rotated to the position shown by the two-dot chain line.
2 to the paper ejection roller 53, and this paper ejection roller 53
The paper is discharged onto the paper discharge tray 48 by the paper discharge tray 48.

When forming an image using a solid black thermal transfer ink ribbon, that is, when creating a film for creating a printing plate, the transfer is performed only once, and the transfer MP does not move back and forth, and the transfer is completed on the paper P. are discharged onto the paper discharge tray 48 as they are.

FIG. 9 shows the operation panel 2, with the mode key (
mode selection switch) 61, color selection key 62 for specifying the color in single color mode, numeric keypad 63 for setting the number of copies, etc., clear key 64 for clearing the set number of copies, etc., copy key 65 for starting the copying operation, number of copies, etc. A numeric display 66 for displaying , a status display section 67 for displaying the operating status, etc., a batch print key for instructing - batch printing (i.e., successively producing a printing master film for each 0 at - times). 72 etc. are provided.

The color selection keys 62 include, for example, a Y key 68 for specifying yellow (Y), an M key 69 for specifying magenta (M), a C key 70 for specifying cyan (C), and a B key 71 for specifying black (B). It is made up of.

FIG. 10 schematically shows the overall control system, in which the main υIt11 section 81, the first printing review section 82 and the second II
It has a control section 83. The main control section 81 includes the operation panel 2, a correction circuit 84, a luminance color difference separation circuit 85, an image quality improvement circuit 86, a color signal conversion circuit 87.2 (IF conversion circuit 88
, the first DI control section 82 and the second sub-control section 83, respectively, and controls these. The first printing section 82 is connected to a light source control section 89, a motor drive section 90, the photoelectric converter 13, an A/D converter 91, and a resolution conversion section 92, and controls these. The light amount control section 89 is connected to the illumination lamp 12 and controls the light amount thereof. A motor drive unit 90 is connected to the scanning motor 18 and drives it. The second sub-control unit 83 is connected to a thermal head temperature control unit 93, the thermal head 31, various detection switches 94, and a drive unit 95, and controls these. The drive unit 95 is connected to a drive system 96 such as a motor and a solenoid, and drives the drive system 96 .

The signal flow in FIG. 10 in such a configuration will be explained. The reflected light of the light irradiated onto the original from the illumination lamp 12 forms an image on the photoelectric converter 13 . Photoelectric converter 1
3 separates this light into analog color signals of cyan (C), green (G), and yellow (Y), and sends the light to an A/D converter 9.
Send to 1.

The A/D converter 91 converts each analog color signal into a digital signal and sends it to the resolution converter 92. The resolution conversion unit 92 performs resolution conversion to match the resolution of the photoelectric converter 13 and the w;I image power of the thermal head 31, and sends the result to the correction circuit 84. Correction circuit 8
4 performs correction processing on each of the C, G, and Y color signals sent from the resolution converter 92 in order to correct variations in the charging converter 13, and sends the results to the luminance and color difference separation circuit 8.
Send to 5. The luminance/color difference separation circuit 85 performs various arithmetic processing on each of the C, G, and Y color signals sent from the correction circuit 84, and outputs a 1 degree signal (I), a color difference signal @1 (C1), and a color difference signal 2 ( C2) is separated into each signal, and the image quality improvement circuit 86
send to The image quality improvement circuit 86 analyzes the luminance signal, color difference signal 1, and color difference signal 2 sent from the luminance color difference separation circuit 85, performs image improvement processing such as edge emphasis and character identification, and sends the processed signals to the color signal conversion circuit 87. . The color signal conversion circuit 87 performs color conversion based on the luminance signal, color difference signal 1, and color difference signal 2 that have been subjected to image quality improvement processing, and converts them into yellow (Y), magenta (M), 9 cyan (C).

Converts it into a color signal of any one of black (B) [three primary colors (Y, M, C) plus 8 for printing], and converts it into a binarization circuit 88
send to The 211I converting circuit 88 receives the 0 signal @ (Y, M) sent from the color signal converting circuit 87.

gradation conversion, that is, binarization, is performed on one of C and B), and the resulting 21i signal is sent to the thermal head temperature control section 93. Thermal head mixed 1:ill
The eight section 93 sends a print signal to the thermal head 31 based on the binarized signal sent from the binarization circuit 88 . The thermal head 31 performs printing (that is, image formation) according to this printing signal.

Here, the color signal conversion circuit 87 will be explained in more detail with reference to FIG. Brightness signal sent from the image quality improvement circuit 86! (1), color difference signal 1 (CI>, color difference signal 2)
Each signal (C2) is sent to a color signal conversion circuit 87, where Y, M.

One of the color signals of C and B is sent to the conversion circuit 88, and the Y, M, and C color signals are sent to the conversion circuit 88.

The selection of the B color signal is performed by the main control section 81.

That is, the main control unit 81 supplies the selection signals @a and b to the color signal conversion circuit 87, and as shown in the table below, the combination of the selection signals a and b causes the Y signal to be sent to the binarization circuit 88.
, M, C, and B color signals are selected. Note that the above color signals are automatically selected sequentially (for example, in the order of Y-+M-+C→B) when in the normal color copying mode or when the batch print key 72 is turned on in the single-color mode. When the batch print key 72 is not turned on in the single color mode, the corresponding color signal is selected in response to the operation of the color selection key 62.

Next, the operation will be explained with reference to the flowchart shown in FIG. First, in step S1, it is determined whether or not the monochrome mode is selected. If the monochrome mode is not selected, it is the normal color copying mode, so step S1 is performed.
Proceed to step 2. In step S2, it is determined whether or not the copy key 65 is turned on, and if it is not turned on, step S1
Returns to step S3, and if it is turned on, the process advances to step S3. In step $3, an image forming operation is performed. That is, in this case, since the mode is color copying, color copying (image formation) is performed using the thermal transfer ink ribbons 34 of a plurality of colors by the above-described operation. The detailed operation of color copying is as follows.
For example, please refer to Japanese Patent Application No. 60-38051.

In step S1, if the single color mode is selected, this is the mode for producing a film for printing original plate production, and the process proceeds to step S4. In step $4, the -batch print flag is reset, and the process proceeds to step S5. In step $5, the color signal conversion circuit 87 is set to Hey Yellow (Y) as an initial setting.
, and the process proceeds to step S6. In step S6, it is determined whether or not the -bulk print key 72 is turned on. If it is not turned on, the process proceeds to step S7, and if it is turned on, the process proceeds to step S8. In step S8, the -batch print flag is set, and the process proceeds to step S7. In step S7, it is determined whether the color selection key 62 has been turned on, and if it has not been turned on, the process advances to step S9. In step S9, it is determined whether the single color mode has been cleared. If it has been cleared, the process returns to step S1; if it has not been cleared, the process proceeds to step S310. In step S10, it is determined whether or not the copy key 65 has been turned on, and if it has not been turned on, the process returns to step $6.

If the color selection key 62 is turned on in step S7, the process advances to step 811. In step S11,
- Reset the batch print flag and proceed to step 312.

In step S12, it is determined whether or not the Y key 68 has been turned on. If the Y key 68 has been turned on, the process advances to step S13. In step S13, the color signal conversion circuit 8
7 yellow yellow (Y) is commanded to be converted into a color signal, and the process returns to step S6. In step 812, if the Y key 68 is not turned on, the process advances to step 814. In step 814, it is determined whether or not the M key 69 has been turned on. If the M key 69 has been turned on, step S15
Proceed to. In step S15, the color signal conversion circuit 87 is commanded to convert hemagenta (M) into a color signal, and in step S6
Return to

In step 814, if the M key 69 is not turned on, the process advances to step S16. In step 816,
It is determined whether or not the C key 70 is turned on, and the C key 70 is turned on.
If it is turned on, the process advances to step 817. In step S17, the color signal conversion circuit 87 is commanded to convert into a Hessian (C) color signal, and the process returns to step S6. In step 816, if the C key 70 is not turned on, the process advances to step S18. In step 818, the B key 7
1 is turned on, and instructs the color signal conversion circuit 87 to convert the signal to a color signal (<8), and then proceeds to step S.
Return to 6.

If the copy key 65 is turned on in step S10, the process advances to step S19. In step S19, it is determined whether the -batch print flag is set, and if it is not set, the process advances to step S20. Step 82
At 0, an image forming operation is performed on one sheet of paper using an image forming signal corresponding to the set color. In other words, in this case, the mode is for creating a film for creating a printing master, so
By the above-described operation, monochrome copying (image formation) is performed using a black thermal transfer ink ribbon. In this case, image formation is performed for the set color components of the original image. For example, if yellow (Y) is set, image formation is performed for the yellow component of the image on the original, and if magenta (M) is set, image formation is performed for the magenta component of the image on the original. In this case,
A solid black thermal transfer ink ribbon is preset,
It is also assumed that, as the paper P, for example, a plastic film is set in advance. As a result, a film for producing a printing original plate corresponding to the set color components of the original image is obtained.

In this way, when the -batch printing key 72 is not turned on, a film for producing a printing original plate for the color selected and set by the color selection key 62 is obtained.

In step S19, if the -bulk print flag is set, the process advances to step 821. In step 821, the signal conversion circuit 87 is commanded to convert the yellow (Y) color signal into a color signal, and the process proceeds to step S22. Step 822
Now, the first image forming operation is performed using the image forming signal corresponding to the set color. In this case, the color signal conversion circuit 8
Since the command is to convert the color signal into a 7-yellow (Y) color signal, image formation is performed for the yellow component of the original image. As a result, a film for producing a printing original plate for the yellow component of the image of the original document is obtained.

In step S22, when the first image forming operation is completed, the process proceeds to step S23. In step 823,
The color signal conversion circuit 87 is commanded to convert hemagenta (M) into a color signal, and the process advances to step 824. In step S24, a second image forming operation is performed using an image forming signal corresponding to the set color. In this case, since the color signal conversion circuit 87 is commanded to convert hemagenta (M) to a color signal,
Image formation is performed for the magenta component of the original image. As a result, a second film for producing a printing original plate for the magenta component of the original image is obtained.

When the second image forming operation is completed in step S24, the process advances to step 825. In step S25,
The color signal conversion circuit 87 is commanded to convert Hessian (C) into a color signal, and the process advances to step S26. In step S26,
The third image forming operation is performed using the image forming signal corresponding to the set color. In this case, since the color signal conversion circuit 87 is commanded to convert to a Hessian (C) color signal, image formation is performed for the cyan component of the original image.

As a result, a third film for producing a printing original plate for the cyan component of the W% draft image is obtained.

When the third image forming operation is completed in step S26, the process advances to step 827. In step 827,
The color signal conversion circuit 87 is instructed to convert the black (B) into a color signal, and the process proceeds to step 828. In step 328, the fourth image forming operation is performed using the image forming signal corresponding to the set color. In this case, since the color signal conversion circuit 87 is commanded to convert the black (B) into a color signal,
Image formation is performed for the black component of the original image. As a result, a fourth film for producing a printing original plate for the black component of the original image is obtained.

In this manner, when the batch printing key 72 is turned on, printing original plate preparation films for each color can be obtained continuously.

As explained above, by optically scanning the original,
It is read as three types of color signals, green and yellow, and these three types of color signals are read as yellow.

It is converted into four-color image forming signals of magenta, cyan, and black, and one of these four-color image forming signals is used to perform m'& formation on a plastic film using a solid black thermal transfer ink ribbon. It is something. This allows for a relatively simple structure without the need for complex production processes such as conventional exposure and development.
A film for producing a printing original plate can be produced very easily, and moreover, it can be realized in a small size and at low cost. Further, by switching with the - batch print key, images are sequentially formed on the same number of plastic films as the four color image forming signals using a solid black thermal transfer ink ribbon based on the four color image forming signals. As a result, it is possible to continuously create a film for creating a printing master plate for each 0 at a time, which saves time compared to creating a film for creating a printing master plate for each 0 one by one. .

[Effects of the Invention] As detailed above, according to the present invention, a film for producing a printing plate can be produced very easily without using the conventional complicated production process, and it can be made small and inexpensive. It is possible to provide an image forming apparatus that can realize the present invention and continuously create a film for creating a printing original plate for each zero at a time.

[Brief explanation of the drawing]

The drawings are for explaining one embodiment of the present invention, and FIG. 1 is a flowchart for explaining the operation, FIG. 2 is a schematic perspective view showing the overall configuration with a part cut away, and FIG. 3 is an external perspective view schematically showing the overall structure, FIG. 4 is a side view schematically showing the structure of the document scanning section, and FIG. 5 is a perspective view showing the scanner moving mechanism of the document scanning section. , FIG. 6 is a longitudinal side view schematically showing the configuration of the image forming section, FIG. 7 is a perspective view for explaining the transfer operation state, FIG. 8 is a plan view showing the configuration of the thermal transfer ink ribbon, and FIG. The figure is a plan view of the operation panel, and Figure 10 is a block diagram schematically showing the overall control system.
The eleventh factor is a block diagram for explaining the color signal conversion circuit in detail. 0...Original, P...Paper (image forming medium), 2...Operation panel, 8...Original scanning section, 9... ...Image forming section, 11...
・Scanner, 31...Thermal head, 34...
...Thermal transfer ink ribbon (image forming medium), 62.
...Color selection key, 72...-Block printing key (changeover switch), 81...Main control section, 82゜83...Sub-11111 section, 87 . . . Color signal conversion circuit, 93 . . . Thermal head temperature control section. Applicant's agent Patent attorney Takehiko Suzue +1 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 10 ↓ Figure 11

Claims (11)

[Claims] (1) A reading means for optically scanning a document and reading it as multiple types of color signals; A color conversion means for converting each color signal obtained by this reading means into image forming signals of multiple colors; Image forming means for sequentially forming the same number of images as the plurality of color image forming signals on an image forming medium using a single color image forming medium according to the obtained plurality of color image forming signals. Features of the image forming device. (2) The image forming means sequentially forms images one color at a time on the same number of image forming media as the plurality of color image forming signals obtained by the color conversion means. The image forming apparatus according to scope 1. (3) The image forming means selects one image forming signal from among the image forming signals of a plurality of colors obtained by the color converting means, and prints the image forming signal on the image forming medium using a single color image forming medium. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus has a mode for forming an image. (4) The image forming means selects a mode in which the same number of images as the plurality of color image formation signals obtained by the color conversion means are sequentially formed and one of the plurality of color image formation signals to form an image. 4. The image forming apparatus according to claim 3, further comprising a selection means for selecting a mode for forming an image. (5) The image forming apparatus according to claim 4, wherein the image forming mode of the selection means is switched by a changeover switch provided on an operation panel. (6) The image forming apparatus according to claim 1, wherein the plurality of types of color signals are cyan, green, and yellow, or three types of red, green, and blue. (7) The image forming apparatus according to claim 1, wherein the plurality of color image forming signals are four colors of yellow, magenta, cyan, and black or three colors of yellow, magenta, and cyan. . (8) The image forming apparatus according to claim 1, wherein the single color image forming medium is made of one color, black. (9) The image forming apparatus according to claim 1 or 8, wherein the image forming medium is a thermal transfer ink ribbon. (10) The image forming apparatus according to claim 1, wherein the image forming medium is paper or a plastic film. (11) The image forming apparatus according to claim 1, wherein the image formed on the image forming medium is used for creating an original plate for offset printing.