Dropping the net, not inking, and printing rate are not enough?

"The problem of losing network, not inking, and insufficient printing rate" was a problem. Many customers first suspected CTP. Some customers even ask during the research stage of purchasing equipment: “What is the printing rate of your equipment?”

This is a maddening issue. To explain it clearly is extremely simple, and as a user of the CTP, it is also necessary to clarify the “mystery” among them.

Let's first understand the exposure mechanism of the plate. With a Huaguang plate that we are all familiar with, for example: Huaguang UV-P plate, suitable for UV-CTP positive plate. The positive image type is a photodecomposition type plate material, and the light-receiving portion of the photosensitive layer is decomposed and removed during development to form a non-image area (hydrophilic area), while the unexposed area is a printing image area (ink area). Thermal plates are similar. Positive type is suitable for commercial printing. Huaguang UV-N type plate, suitable for UV-CTP negative type plate, negative type is photopolymerization / light cross-linked plate, light-sensitive part of the photopolymerization / light cross-linked to form a print graphic area , while the unexposed area is removed during development, not the image area. Negative type suitable for packaging printing.

Use jargon to explain the above terminology. The positive plate (UV or thermal), the laser beamed part is rinsed out to reveal the aluminum base, and the fountain solution is applied on the printing machine; the laser does not touch the part. The coating is left on the plate and corresponds to the ink on the printing press. Explain that white, the part that the laser has not touched is not inked or lost. How can this be related to CTP?

Maybe someone is anxious. You said that it doesn't matter to you and who is related to it!

The lack of imprinting rate, the loss of printing plates, bad pictures and non-inking are all comprehensive factors. In fact, it is not difficult to find problems. Many incorrect production habits and errors in production will lead to these problems.

(1) Plate machine: Excessive flushing is the most common cause. The stencil machine is not the “adjustment stage” in the production process. Some customers use the shade, temperature, and speed of the liquid to adjust the bottom ash when they see the bottom ash in the layout; in order to increase the production efficiency, the temperature of the plate processor is increased, and the flushing speed is increased. ; In order to save costs, work hard from the liquid; in order to save the money to save water washing and protection adhesive and so on. Some stencil machines are not properly maintained, and crystallization, excessive brush pressure, etc., can cause excessive flushing.

(2) Wash a variety of plates with a potion. There are differences in the anti-alkaline parameters of different plates, which will inevitably lead to excessive flushing.

(3) Different plates use the calibration curve and the same focal length file output.

(4) Printing presses: The pH of the fountain solution is too large, the physical wear of the printing plate is too large (blanket, underlay, pressure, speed, paper), the cleaning paste is used incorrectly, and the alcohol content is too high. The alcohol resistance of the material).

(5) The alkali resistance of the plate can be known through a simple flush test. Take a plate directly into the plate processor and rinse it 2 or 3 times. If it becomes a white plate, you should be careful.

(6) Tips: Try a different type of media; take a look at what is always the problem is not a fixed printing or printing machine.

(7) If your company has a high printing rate or a scarcity of machine time, and you value the quality, it is recommended that you use a good plate processor, a relatively stable plate, a matching potion, and check the printer fountain solution. PH value, baking version. These suggestions plus the baking version of each edition seem to be harsh and superfluous, oh, do and do it until you know it.