Some Suggestions About Newspaper Making

Newspaper printing Due to the different conditions of printing machinery, printing paper and ink, there is a certain difference between prepress processing and general commercial printing before printing. Here, we discuss according to some features of newspaper printing. Take a look at some of the issues in newspaper prepress and make some suggestions for your reference.

1. Black and white field settings during scanning

Most newspaper printing uses newsprint and web presses. The minimum dot reproducible is 6%-8%. Therefore, when scanning, the percentage of dots in the high-light part of each color version cannot be less than 6%. If the dots are too small, the highlights will be caused. Small outlets are missing and there is no network. Due to the particularity of newspaper printing, it is necessary to pay attention to the total amount of ink during platemaking. The total amount of four-color ink should be between 270%-300%, and the maximum amount of black ink can be set between 90%-95%. , And can increase the amount of background color removal to reduce the ink layer thickness.

2 when the output film control

The general newspaper's output accuracy is 85LPI-120LPI, and dot angle is not much different from ordinary offset printing. Generally it is a blue version: 15° (or 75°), a magenta version: 75° (or 15°), a yellow version: 0°, Black version: 45°, you can also adjust the dot angle according to the main color version. For the field density requirements of the film, the general can be more than 3.5, some newspapers only require 3.2 or more, and the film base fog should be controlled below 0.08.

3. Imposition

With the development of electronic technology, imposition work can now be accomplished by computer software and then output using an imagesetter or CTP. The layout format of the newspaper is basically fixed. Therefore, only one template must be created in the computer. The page size, layout size, head, foot, fold line, and incision are determined, and the content of each page is fixed. The full information required for printing (such as crosshairs, corners, color labels, etc.) can be used, and each layout can be applied to this template, which is very convenient. The work of hand-made imposition is now rare. However, it should be noted that some advertisers provide manuscripts that have already been exported with good four-color films. There are two solutions to this problem: First, use a dot-copy scanner to scan the film into electronic files and then use it in a computer. Combining with other content in the layout, this method has high accuracy of registration and can be directly published by CTP. There is no indirect sewing in the printing and no revision is required. There is also a method to manually put together two sets of films. This method has low accuracy of registration, and it is easy to lose the adhesive film, and it needs to be revised after printing. If conditions are available, the first method is recommended.

4. Printing

During the printing of the newspapers, attention was paid to the use of Bruner printing control strips to control the printing plates. The 0.5%-5% fine dot area and the micron line pattern were used for control, requiring that 3%-5% of the dots could be reproduced. 97% --98%0 outlets do not stick. This is a good way to restore the image tone. When using the customer-supplied film to manually make imprints and then printing, it is necessary to note that some advertising companies produce laser printing film. The density of the laser printing film is lower than the density of the film. First, it cannot be overlapped during the imposition, otherwise it is easily caused when printing. Inhalation is not true, resulting in the picture is false; second, the density of the printing film is not the same as the density of the film, the exposure time when printing is also different, the film density is large, the printing time is longer, the printing film density is small, The printing time should be shortened correspondingly. In principle, after the printing, the text is required to be clear. There is no shortage of paintings and the writing is full.

5. Baking version

Roasted version is to improve the printing plate printing rate. The print volume of newspapers is relatively large. If the printing plate has a high printing rate, the number of disassembling plates can be reduced, saving time, reducing the amount of waste, saving production costs, and controlling the ink color. Baking temperature is generally about 200-220 °C, baking time is 10-15 minutes.

6. Development

The daily printing materials of newspapers are different, so the consumption of developer is very large. Therefore, it is necessary to pay attention to the change of developer concentration. According to the situation of developed films or plates, the status of the punching machine can be adjusted in time, or replaced. Liquid medicine to ensure the quality of the newspaper.

7.CTP

Now that CTP technology is more and more mature, it simplifies some of the process of plate making, shortens the plate-making time, and improves the accuracy. It also reduces the network loss caused by numerous processes, makes the site more reliable, and the plates are more tidy. CTP technology is used by many newspapers in newspaper printing. Among various types of CTP equipment, the violet laser CTP equipment has stable light source, long laser life and low price, and the dot reproduction range can reach 1%-99%, and the price of the plate is low; now the major CTP manufacturers promote the thermal type. CTP equipment can be operated in the bright room, with large exposure latitude and very high resolution, but the speed is slower. Newspapers can choose according to their own needs. When the newspaper chooses CTP equipment, it also needs to carefully select a good digital process, and pay attention to the convergence of each link so that the CTP can play its strengths.

Author: Shimizu