JP3065784B2 - Color proof creation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preparing a color proof for color proofing performed prior to color printing.

[0002]

BACKGROUND OF THE INVENTION In the field of the printing industry, proofreading prior to actual printing is an indispensable operation for preventing errors such as typographical errors, typographical errors, typefaces, layouts and the like. Further, in color printing, a check (color proof) relating to colors such as color tone and gradation is required in addition to the normal proof.

In conventional color proofing, proof printing (test printing) is performed using actual printing ink to check the color tone and the like. However, workability is poor and it takes time, and the cost is high. there were. Therefore, as a method for solving this, various systems for performing color proofing with substitutes that do not use printing ink have been announced and sold. For example, CRT images, photopolymers,
Those using non-silver salt photosensitive materials such as diazo, those forming images with dry toner, those using electrophotography,
The color original is color-separated to produce a color separation mesh original consisting of four plates of Y, M, C and black, and this original is obtained by overlapping exposure and development on a color photosensitive material coated with a silver halide emulsion. There is a method of performing proofreading with printed photographs. Each of these color proofing systems has advantages and disadvantages, and many different solutions have been proposed.

[0004]

SUMMARY OF THE INVENTION The present invention relates to the last method of the above-mentioned color proofing system, that is, Y, M, C (yellow, magenta, cyan) by color separation of a color original.
And a color separation screen manuscript consisting of four plates of black and black, and proofreading the manuscript with a print photograph obtained by overlapping exposure and development on a color photosensitive material coated with a silver halide emulsion (Japanese Unexamined Patent Publication No. 196066).

[0005] Even if the color proof by a print photograph is OK, dissatisfaction may occur in the color tone or the like when actually printing. For example, there is a considerable difference between the color paper for creating a print photograph and the printing paper for actually performing printing, even for the same white color, due to the difference in ground color between the two.

[0006] There is a limit to the white color developed by color paper, and the same color as printing paper cannot be obtained.

Therefore, conventionally, a difference in color tone or the like due to a difference in ground color between printing paper and color paper has been determined based on the skilled experience of a color proofreader.

The method relying on the skill of a color proofreader is problematic because of the shortage of skilled technicians, and there are many mistakes. Finally, instead of using a proofing machine using a color photosensitive material, a printing proofing machine is used. I was judging.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has been made to overcome the problem of color proofing caused by the difference in ground color between color paper and printing paper. It is an object of the present invention to clarify an improved color proof creating apparatus which can set an exposure condition based on a difference in ground color with a simple operation using only a single color paper without using it.

[0010]

According to the present invention, there is provided an apparatus for producing a color proof, comprising: a background color selected in accordance with density measurement information of a background color of printing paper in parallel with normal exposure of each of Y, M, and C plates; A configuration for performing ground color correction by performing exposure using a flat screen chart of an equivalent color; a plurality of flat screen charts having different densities are prepared in the apparatus for each of Y, M, and C plates; A flat chart selected according to the ground color measurement information of the printing paper is automatically supplied to the exposure position. The ground color exposure is performed in advance so that the Y, M, and C plates can be exposed with the normal exposure index. Normally, the halftone dot% of each plate with respect to the reference exposure index is stored in the control system, and the exposure operation is automatically controlled according to the background color density measurement information of the printing paper.

[0011]

Next, a specific configuration of the present invention will be described in detail.

An example of a color proof producing apparatus to which the present invention is applied is disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 1-196066.
The configuration of the present invention described below can be easily implemented simply by incorporating it in this device. Although the apparatus will be described with reference to FIGS. 1 and 2, the apparatus to which the present invention is applied is not limited to the illustrated apparatus. The design of the illustrated apparatus is also variously changed depending on the type of photosensitive material used.

Inside the light-shielded main body frame 10,
The photosensitive material mounting table 20, the transporting means 30, the processing unit 40, and the like are arranged. The photosensitive material 50 is stored in a magazine 51 and prepared on a side surface of the main body frame 10. An original table 60 made of transparent glass is provided on the upper surface of the main body frame 10.
A light source mechanism 70 and a cover sheet mechanism 80 that linearly reciprocate along a rail arranged on the side of the light-shielding cover 90 are provided.
Thus, the light-shielded state is maintained.

The photosensitive material 50 is prepared in a magazine 51 with its leading end engaged with a take-out roller 52. By rotating the take-out roller 52, first, the leading end of the photosensitive material 50 is transferred to the traveling head 31 of the conveying means 30. Prepared sucker 32
, The tip is fixed by suction by the suction cup 32, the traveling head 31 is pulled out of the magazine 51 as the traveling head 33 moves along the traveling rail 33, and is pulled out to a predetermined position of the photosensitive material mounting table 20. The drawing is stopped by the sensor, and the rear end of the photosensitive material 50 is cut by the cutter 57. The photosensitive material 50 thus supplied to the photosensitive material mounting table 20 is sucked by the operation of the vacuum pump 21 and is fixed at a predetermined position on the upper surface of the photosensitive material mounting table 20. Motor 59
Is guided to a predetermined position on the lower surface of the document table 60 as it rises. As shown in FIG. 2, a light-shielding member composed of an endless belt that rotates according to four guide rollers is disposed on the lower surface of the document table 60, and the light-sensitive material is mounted even when the light-shield cover 90 is opened. Table 20
Light is prevented from entering the side. During exposure,
The endless belt is moved by a predetermined amount, and the portion where the opening is prepared is guided to the lower surface of the document table 20.

When the exposure of the photosensitive material 50 is completed,
The suction by the vacuum pump 21 is released, and the conveyance roller 35 of the conveyance chute 34 with which the tip of the photosensitive material 50 is engaged.
Is pulled out of the light-sensitive material mounting table 20 and dropped into the transport chute 34 with the rotation of. The photosensitive material 50 dropped on the lower surface of the transport chute 34 is transported by the reverse rotation of the transport roller 35 so that the emulsion surface is directed upward, and is sent to the processing unit 40 by switching the transport path. The second exposure by the exposure means 41, color development in the development processing section 42, development processing such as bleach-fixing and stabilization, and drying section 4.
After the drying process in step 3, it is carried out of the apparatus.

The apparatus has been described in accordance with the flow of the photosensitive material 50. Next, the configuration of the exposure unit will be described.

As described above, the exposure unit is disposed on the upper surface of the main body frame 10 inside the light-shielding cover 90 which can be freely opened and closed. In the illustrated apparatus, a contact exposure system in which a light source moves is adopted. .

As shown in FIG. 2, the light source lamp 71 is attached to a central portion of a reflecting mirror 72 having a transmission window provided on the lower surface, and a filter 73 is provided. The light of the light source lamp 71 is projected from the transmission window at the lower end of the reflecting mirror 72,
The light reaches the document table 60 through the exposure window 74. The exposure window 7
The passage of light from 4 is controlled by a shield activated by a solenoid 75.

A rail is arranged along the side of the document table 60. A light source mechanism 70 linearly reciprocates along the rail to perform exposure. And / or the moving speed of the light source mechanism 70 is adjusted.

Next, the setting of a halftone original on the original table 60 will be described.

To set a halftone original on the platen 60,
First, the light-shielding endless belt is controlled so that light does not enter the photosensitive material mounting table 20 side on which the photosensitive material 50 is disposed, and then the light-shielding cover 90 is opened to release the document table 60. As a matter of course, at this time, the light source mechanism 70 has returned to the start position.

The document table 60 is provided with a plurality of registers 61 along its outer periphery. A halftone dot can be obtained by simply inserting a through hole prepared on the side of a halftone document to be exposed into the register 61. The document is configured to be positioned.
When the halftone original is set on the exposure table 60, the cover sheet mechanism 80 is operated. The cover sheet mechanism 80 includes a head 81 that moves along a rail disposed in parallel with the side of the document table 60, and a cover housed in the head 81 and having a front end fixed to a stopper 82. When the head 81 is moved along the rail, the cover sheet 83 is taken out according to the rotation of the squeeze roller 84, and is placed on the upper surface of the document table 60. The upper surface of the placed halftone dot document is covered. When the covering with the cover sheet 81 is completed, the vacuum pump 62 shown in FIG. 1 is operated, and the air on the upper surface of the document table 60 covered with the cover sheet 81 is sucked. It will be.

Next, how the present invention is applied to the above-described apparatus will be described. First of the features of the present invention
Means that, in parallel with the normal exposure of each of the Y, M, and C plates, exposure is performed by a flat-screen chart of a color corresponding to the ground color selected according to the density measurement information of the ground color of the printing paper, and ground color correction is performed. However, to implement this, first, it is necessary to measure the density of the ground color of the printing paper. C It must be prepared for each version. Exposure using the flat color chart for ground color correction may be performed before or after exposure of each of the Y, M, and C plates, and may be performed in parallel.

The flat halftone chart needs to be prepared in the order of halftone dot% for each of Y, M, and C so that the flat halftone chart can be easily taken out and set on the document table 60 in accordance with the ground color density measurement information of the printing paper. There is.

Next, a second feature of the present invention is that a plurality of flat screen charts having different densities are prepared in the apparatus for each of Y, M, and C plates, and the background color of printing paper is measured. The flat-screen chart selected according to the information is automatically supplied to the exposure position. In order to perform this, Y, M, C
A flat screen chart tray is prepared for each plate, and the dot%
In order, the flat screen chart selected according to the ground color measurement information of the printing paper input by the operator is selected by a specific flat screen chart selecting means and a conveying means using a suction cup, a conveying roller, or the like. , A mechanism for automatically guiding to the exposure position is required. Various known mechanisms can be freely selected as the selection means and the conveyance means within a range that does not impair the miniaturization of the apparatus. Note that the exposure position is not necessarily Y
-It does not mean only the upper surface of the exposure table 60 on which each of the M and C plates is set. The necessity of the flat screen chart is simply a matter of density adjustment, and is different from a halftone document which requires the alignment of the Y, M, and C planes. This is advantageous in designing a mechanism. Therefore, for example, the flat screen chart is not only designed to be automatically arranged on the upper surface of the exposure table 60, but also related to the lower surface of the exposure table 60, and the upper and lower sides of the endless light shielding curtain, and furthermore, the light source mechanism 70 traveling. It becomes possible to arrange.

The flat-screen chart does not necessarily have to be a single leaf, but may be formed into a long belt or even an endless belt. In addition, for example, if the upper and lower sides of the endless shading curtain are run, control can be performed separately from the Y, M, and C halftone originals.

In the mode in which the flat-screen chart is arranged in relation to the light source mechanism 70, a sheet- or belt-shaped flat-screen chart can be displayed in synchronization with the traveling speed of the light source mechanism 70, for example.
A configuration in which the light source mechanism 70 travels under the exposure window 74 in the direction in which the light source mechanism 70 travels, or a flat screen chart having a width corresponding to the exposure window 74 of the light source mechanism 70 is prepared.
It is possible to adopt a configuration in which 0 is intermittently repeated while running, stopping, and exposing are repeated. A third feature of the present invention is that a halftone dot% of each plate with respect to a normal reference exposure index is stored in advance in a control system so that ground color exposure can be performed with a normal exposure index of each of Y, M, and C plates. The exposure operation is automatically controlled in accordance with the background color density measurement information of the printing paper. This can be implemented by performing the above-described second feature of the present invention by automatic control. is there. That is, when the exposure of the flat chart is performed under the same conditions as the exposure conditions of the Y, M, and C plates, the normal exposure of the Y, M, and C plates is performed in advance. By storing the dot percentage with respect to the exposure index in the control system, the density measurement information of the printing paper can be manually or automatically input to the control system to determine which flat dot chart should be selected. The control system can determine and automatically set a specific flat dot chart at the exposure position.

[0028]

According to the apparatus of the present invention, by utilizing a plurality of flat screen charts having different halftone percentages facilitated for each of Y, M, and C plates, it is possible to print on printing papers having different ground colors. Since the color proof can be easily prepared and the color proofing can be performed more reliably and in a short time, the problem described above is solved.

[Brief description of the drawings]

FIG. 1 is a schematic front view of an apparatus to which the present invention is applied.

FIG. 2 is a partially enlarged side view of the same.

[Explanation of symbols]

 10-body frame 20-sensitive material mounting table 21-vacuum pump 22-motor 30-transport means 31-travel head 32-suction cup 33-travel rail 34-transport chute 35-transport roller 36-transport roller 40-processing unit 41- Exposure means 42-Development processing part 43-Drying part 50-Photosensitive material 51-Magazine 52-Extraction roller 53-Cutter 60-Document table 61-Register 62-Vacuum pump 70-Light source mechanism 71-Light source lamp 72-Reflecting mirror 73- Filter 74-Exposure window 75-Solenoid 80-Cover sheet mechanism 81-Head 82-Clamp 83-Cover sheet 90-Light shielding cover

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03B 27/73 G03F 3/10 H04N 1/40 H04N 1/46

Claims (3)

(57) [Claims] 1. In parallel with the normal exposure of each of the Y, M, and C plates, exposure is performed by a flat screen chart of a color corresponding to the ground color selected according to the density measurement information of the ground color of the printing paper, and ground color correction is performed. An apparatus for producing a color proof, comprising: 2. A plurality of flat screen charts having different densities are represented by Y
Wherein the flat-screen chart selected according to the ground color measurement information of the printing paper is automatically supplied to the exposure position. The apparatus for producing a color proof according to claim 1. 3. The control system stores in advance a dot% of each plate with respect to a normal reference exposure index in a control system so that ground color exposure can be performed with a normal exposure index of each of Y, M and C plates. 3. The apparatus according to claim 1, wherein the exposure operation is automatically controlled in accordance with color density measurement information.