JPH11341293A - Color matching method for main print printed matter and proof print printed matter by utilizing plate making data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce the main printed matter of the same color as a proof printed matter, to reduce costs and time and to improve efficiency by considering a printing direction before forming a main print printing plate and adjusting plate making data. SOLUTION: The data conversion means 1 of a direct printing means 10 is constituted of a computer, and based on data for which the plate making data prepared in a pre-press system and finalized are converted and turned to dot images by a prescribed software program, the dot area rate of respective assembled patterns in the case of outputting an assembled main printing plate through a machine plate output means is calculated, the area rate of the dot images of the respective patterns is adjusted and the dot area rate of the respective patterns on the assembled main print printing plate is adjusted. Then, by the machine plate output means 2, the main print printing plate assembled by faithfully reflecting the dot area rate is outputted based on generated dot image data. Thus, the colors of the main print printed matter and a proof print printed matter are matched.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a printing plate for producing a printing plate using a prepress system which has been completed by a prepress system using a computer in a printing process. Before making the stencil printing data, the plate making data is taken into consideration in consideration of the difference in the reproducibility of the colors of the proof-printed material and the final printed material in the printing direction or / and the printing width direction of the printing press, and the printing patterns. The present invention relates to a color matching method between a final print and a proof print using platemaking data for preparing a final print plate that can be adjusted to print the same print as the proof print.

[0002]

2. Description of the Related Art In general, in a prepress process, plate making data is prepared by a prepress system using a computer, and a proof print is printed. And sends it to the printing plate process. In the printing plate process, the printing plate film is brought into close contact with a printing plate material and multi-sided printing is performed to produce an imposed final printing printing plate. When printing is performed by a production printing press using the production printing plate prepared in this way, a difference occurs in the reproducibility of the printing halftone dots. Also, due to the structural difference between the proof printing press and the final printing press,
The color difference between the proof prints and the final prints occurs. Therefore, depending on the layout of the imprinted pattern in the final print direction and print width direction, and even if the layout of the pattern of the proof print and the final print is the same, the colors in the proof print may not be able to be reproduced. is there. Conventionally, if you cannot start the actual printing and cannot reproduce the colors in the proof printing,
In such a case, the printing was temporarily stopped, the tone of the unreproducible pattern was adjusted, and the printing plate was re-created. Therefore, there is a problem that the actual printing must be stopped and a countermeasure must be taken, and a problem that the amount of plate material consumed increases.

In general, in a printing process, a final printing plate imposed by a direct printing means is output based on platemaking data created and completed by a prepress system using a computer, and the book printing process is performed. When printing with a printing plate, the color of a proof print may not be able to be reproduced depending on the arrangement of the imposed pattern in the final printing direction or the printing width direction. In this case, conventionally, the process has been returned to the prepress process, the plate making data is corrected on the prepress system, and the printing process has been performed again to output the final printing plate by the direct plate means. therefore,
There is a problem that it takes a long time to output the final printing plate again by the direct printing plate means, and a problem that the final printing must be stopped.

[0004]

SUMMARY OF THE INVENTION The present invention is directed to a printing plate manufacturing method, wherein a final printing plate is produced by using a prepress system which has been completed by a prepress system using a computer and has been completed. Before making a printing plate,
An object of the present invention is to make it possible to create a final printing plate capable of reliably printing a final printing product having the same color as a proof printing product in a printing plate process.

[0005]

Means for Solving the Problems In order to achieve the above object in the present invention, first, the invention of claim 1 is a plate making process which is completed by a prepress system using a computer in a printing plate process. In making the final printing plate using the data, before making the final printing plate, by adjusting the plate making data in consideration of the printing direction of the final printing means, it was completed. A color matching method between a final print and a proof print using plate making data, characterized in that a final print plate on which the same print as the proof print is printed is produced.

According to a second aspect of the present invention, in the printing plate process, the final printing plate imposed by the direct printing plate means using the prepress data created and completed by the prepress system using a computer. At the time of output, before outputting the imprinted printing plate imposed by the direct printing plate means, by taking into account the printing direction of the real printing printing means, adjusting the plate making data, A color matching method between a final print and a proof print using platemaking data, characterized in that an imprint final print plate on which the same print as the new proof print is printed is produced.

According to a third aspect of the present invention, in the first or second aspect of the invention, the adjustment of the plate making data is performed in such a manner that each picture imposed on the printing plate is adjusted in consideration of the printing direction of the final printing means. The color matching method of the final print and the proof print using plate making data, which is the adjustment of the dot area ratio in the halftone dot image data.

According to a fourth aspect of the present invention, in the printing plate process, when a final printing plate is produced using a prepress system which has been completed by a prepress system using a computer, the final printing plate is used. 2. The method according to claim 1, wherein the printing direction and printing width direction of the final printing means are taken into account before making
Alternatively, a color matching method between a final print and a proof print using the plate making data described in claim 2 or 3.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of a system for implementing the method of the present invention will be described with reference to the block diagram of FIG.

The direct printing plate means 10 comprises a data converting means 1, a printing plate output means 2, and the like.

The data converting means 1 receives platemaking data created and completed by a prepress system using a computer, converts the platemaking data into halftone image data, and performs imposition based on the halftone image data. When the final printing plate is output by the printing plate output means 2, the halftone dot area ratio of each imposed picture is calculated and displayed, and the size of the halftone dot in the halftone image data of each picture is calculated. There is a function of adjusting the halftone dot area ratio of each picture in the imprinted printing plate by adjusting the halftone dot area rate in the halftone image data of each picture. The data conversion means 1 is a computer, and the above functions are realized by software. Examples of software for converting the plate making data into halftone image data include RIP
(Raster Image Processor).

The printing plate output unit 2 outputs a final printing plate imposed based on the halftone image data generated by the data conversion unit 1 while faithfully reflecting the halftone dot area ratio of the halftone image data. It is a means to do.

In the method of the present invention, the color matching between the final print and the proof print is performed by adjusting the plate making data using such means. Hereinafter, a specific example will be described. It is assumed that two pictures are arranged along the printing direction of the final printing, a picture to be printed first is G1, and a picture to be printed later is G2. Data conversion means 1
Immediately after the plate making data is converted into halftone image data by using the halftone dot area ratio R
1, the dot area ratio in the dot image data of G2 is R2. At this time, if it is G2> X _2, G1 is greatly affected by G2, the halftone dot area ratio in the final printing printed matter is larger than the dot area ratio in proof print. Therefore, the coefficient t is added to R1 by the data conversion means 1.
Multiplying by ₁ (0 <t ₁ <1) to convert R1 to t ₁ R1,
The printing plate output means 2 outputs a final printing plate based on the t ₁ R1 and R2. Similarly, if it is G1> X _1, G
In No. 2, the halftone dot area ratio in the final print becomes larger than the halftone dot area ratio in the proof print, greatly influenced by G1. Therefore, the data conversion means 1
R2 and multiplying coefficient t ₂ a _{(0 <t 2 <1)} , the R2 t ₂ R
2 and the final printing plate is output from the plate output unit 2 based on the t ₂ R2 and R1. Where X ₁ and X
₂ should be determined by checking the state of proof printing or final printing, and may take a certain value between 50% and 90%, for example.

Next, the procedure of the method of the present invention will be described with reference to the flowchart of FIG.

STEP 1: The data conversion means 1 receives the prepress data which has been created and completed by a prepress system using a computer, and converts the prepress data into halftone image data.

STEP2: In the data conversion means 1,
When the final printing plate imposed based on the halftone image data is output by the printing plate output means 2, the halftone dot area ratio of each imposed picture is calculated and displayed. Then, based on the position of each pattern in the final printing direction and the dot area ratio of each pattern, the influence of the printing pressure, the number of revolutions, and the film thickness or properties of the ink on the halftone dots in the final printing is considered. Then, when printing is performed using the imprinted final printing plate, a picture that causes a color mismatch between the printed print and the proof print is specified.

STEP3: The size of the halftone dot in the halftone dot image data of the picture in which the color mismatch occurs is adjusted so that the colors of the imprinted final print and the proof print match. The dot area ratio in the dot image data is adjusted.

STEP 4: The adjusted halftone image data is sent to the printing plate output means 2, and the halftone dot area ratio of the adjusted halftone image data is faithfully reflected based on the adjusted halftone image data. Then, the imprinted printing plate is output.

[0019]

Next, a specific embodiment of the method of the present invention will be described with reference to FIG.
This will be described in detail with reference to FIG. O1 and O2 are prints that have been completed and have been printed on a proof printing press at a low rotational speed or a digital color printer (for example, pressureless printing). A is a final printing plate.

The picture G of the proof print O1 that has been completed
1, the dot area ratio of the pattern G2 of the proof print O2, which has also been completed, is 10%,
The printing press A is printed at a high speed by the printing press, in which a pattern G1 having a dot area ratio of 100% and a pattern G2 having a dot area ratio of 10% are sequentially imposed along the printing direction P. Trying to.

However, when the final printing is performed on the printing plate A, the dot area ratio of the pattern G1 in the printed matter is 100%, but the dot area ratio of the pattern G2 in the printed matter is affected by the pattern G1. Suppose that it is determined to be 12.5%. At this time, the pattern G2 of the final printing plate A
The halftone dot area ratio R1 in the halftone image data, t ₁ =
By multiplying by 0.8 and changing the printing plate A from 10% to 8% and outputting the printing plate A, the printed matter of the printing plate A can reproduce the same color as the proof print.

[0022]

According to the method of the present invention, in the printing plate process, when making a final printing plate using the prepress data which has been completed by a prepress system using a computer and has been completed, the printing plate is prepared before the printing plate is made. By adjusting the plate making data to create a final printing plate that can print the same color as the proof print in the printing plate process,
The color tone of the final print and the proof print can now be matched, eliminating the need to adjust the burnout of the photographic printing plate by baking and developing using the conventional optical photographic method. This eliminates the need for color correction that goes back to the pre-press process, as described above, and has the effect of reducing the time and cost required for such work and improving the quality of the final print. .

[Brief description of the drawings]

FIG. 1 is a block diagram of a system for performing the method of the present invention.

FIG. 2 is a flowchart showing the procedure of the method of the present invention.

FIG. 3 is an explanatory view showing an embodiment of the method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Data conversion means 2 ... Printing plate output means 10 ... Direct printing plate means A ... Final printing plate G1 ... Picture G2 ... Picture O1 ... Proof printing O2 ... Proof printing P ... Final printing direction

Claims (4)

[Claims] In a printing plate process, when making a final printing plate using a prepress system which has been completed and completed by a prepress system using a computer, a final printing plate is produced before the final printing plate is produced. Adjusting the prepress data in consideration of the printing direction of the prepress printing means, thereby producing a preprint printing plate capable of printing the same printed material as the proof print product that has been completed, Color matching method for printed matter and proof print. 2. In the printing plate process, when outputting a final printing printing plate imposed by direct printing plate means using platemaking data which has been created and completed by a prepress system using a computer, Before outputting the imprinted final printing plate by the direct plate means, by considering the printing direction of the final printing means, by adjusting the plate making data, the proof print having been completed and A color matching method between a final print and a proof print using plate making data, wherein an imprinted final printing plate is formed on which the same print can be printed. 3. The method according to claim 1, wherein the adjustment of the plate making data is an adjustment of a dot area ratio in the dot image data of each pattern imposed on the final printing plate in consideration of a printing direction of the final printing means. A color matching method between a final print and a proof print using the plate making data according to claim 2. 4. In the printing plate process, when making a final printing plate by using a prepress system which has been completed by a prepress system using a computer, and before making the final printing plate, 4. A color matching method between a final print and a proof print using platemaking data according to claim 1, wherein the print direction and the print width direction of the print printing means are taken into account.