Make sure the position of the sun is accurate 8 times when drying

Once, the Tongliang County color printing factory in Chongqing printed a 32-page book with a front ring lining and a front page. The front ring lining had no content, and the front page had a single-color screen pattern, printed on the same paper. Due to the limitation of time and quality, the front ring lining and the front page can only be printed on folio paper, but the front page film only has 32 sets. If you use manual copying of 8 sheets, it is easy to have inconsistencies in the depth of the dots and so on. When the version of the sun even 8 times, to get a split version. How can we ensure that even the position of the sun is accurate without affecting the quality?

1. Check the film sheet

The title page is a 32-mesh screen with a size of 210mm x 145mm, and there are dots around it.

4 gauge lines and 4 corner lines.

2. Design even drying program

Since the left side of the front ring lining and the leaflet printed product is blank, the right side is a 32-inch leaflet pattern.

The open version of the drying, can be dried 8 sets, even the drying can only use the left and right 2 gauge, because the upper and lower 2 gauge

The positions of the four corners have been occupied by the pattern, and there is no gap or overlap between adjacent patterns, ie seamlessly

Then. Since the 32-day book only has 4mm openings, considering the binding error, the adjacent parts of the two patterns

The width of the repairable parts of the dots must not exceed 2mm each, and the positional deviation degree of each pattern is also required.

this. Therefore, even the drying of the cover method, accuracy and pattern position accuracy requirements are high.

3. Even drying operation

(1) Since only the left and right 2 gauges are available, first connect the left and right gauges together and copy 8 copies.

(2) On the standard coordinate paper, paste the copied 8 gauge film on a transparent film base.

Accurate size and position, so that the relative reference position of the sun is determined.

(3) Placing the assembled gauges on the PS plate according to the requirements of the printing machine and the side gauges, using black paper

Or red mask will cover the PS plate, only exposed the gauge line, and pay attention to less exposed, to prevent the photosensitive plate overprinted

Multiple exposures, resulting in a waste version. After printing, show the gauge line and dry the plate for use.

(4) Use golden color polyester adhesive (because its thickness is much smaller than black paper, board paper, easy to paste, and shading

Sex meets the requirements, does not affect the quality of the network) stick to the upper and lower blank parts of the film, to paste the film surface. This

It can make the cover more accurate without affecting the quality of the outlets, and it can also facilitate the cover in the next step, and can avoid

Freedom to influence outlet restoration due to improper cover. After gluing, use a sharp knife against the edge of the pattern with a ruler

Lightly scratch the mask to remove the pattern and leave behind a blank sticker.

(5) Match the gauge line of the film processed in step 4 with the tanned line in step 3 to determine the width of the sky,

After the footing, stick the film firmly to the PS plate. After checking and confirming that the gauges are completely coincident, use black

The paper or red film will cover the pattern that is to be exposed and the space that corresponds to the blank part of the front ring lining (note

The black paper or red film is as far away from the edge of the pattern as possible, otherwise it will make the dots shrink and become imaginary. If you go back

If no sticker is applied, the cover must be close to the edge of the pattern, but it is easy to make the edge of the pattern.

Now the loss width is more than 2mm, which becomes waste version). Check and confirm that the masking can be performed for the first time.

Light. Because the film edge of the film has been pasted, the degree of vacuum in the plate press should be adjusted slightly.

(6) Repeat step 5 until a pair of exposures has been exposed (note the same exposure time), then

development. After development, it is necessary to check: 1 If each benchmark is complete, if it is not complete, observe the deviation carefully.

Degree, deviation is too large, the version has been scrapped, need re-lighting. 2 whether the pattern is lost, especially adjacent

Part of the loss situation. If the loss exceeds 2mm, the version is also scrapped.

As long as each step operation method is accurate, even printing plates basically meet the printing requirements.

Reprinted from: China Print Information Network