CTP Machines

CTP types and difference

Difference of CTP laser diodes and laser valve head

Compared with fiber optic technology, it is easier to control the average energy of each optical path and the dot quality is more consistent, so the printing quality is guaranteed. In terms of accuracy, this technology can break through high-precision requirements, with fine light spots that can reach 12800dpi. It can achieve satisfactory results when applied to high-demand special printing. Using a single light source laser, coupled with the flexibility of light source energy selection and stable power control, more equipment with different output speeds can be provided to meet different customer requirements.

Rectangular dot imaging technology, the fineness and accuracy are increased by 10 times. The 256-channel laser external modulation technology is a square light spot, and the energy distribution is in the shape of a rectangular step. In this way, the edge of the light spot is sharper and the image is clearer. The fineness and accuracy of the 200lpi AM dots are improved by 10 times. times, color saturation can be increased by more than 21%. At the same time, the 256-channel laser external modulation technology can accurately match the resolution of the actual document , so that the length-to-width ratio of the rectangular dots can be adjusted to achieve perfect variable resolution printing.

The 256-channel laser external modulation technology breaks the limitations of traditional CTP fiber technology and can generate 180-320 laser beams at the same time, increasing the plate making speed to 2 times; the 256-channel laser external modulation technology achieves rapid plate making while reducing the drum speed to 300-500 revolutions per minute, only 30%-50% of the CTP speed of traditional optical fiber technology. The CTP equipped with a 256-channel laser external modulation platform and low rotation speed make the equipment stable, low energy consumption, and less wear-and-tear.

Special technology of flexo CTP

Hybrid flexographic screening technology uses frequency modulation screening technology to screen the highlight parts of the image (less than 10% to 15% of dots), and uses traditional amplitude modulation screening in the mid-tone and dark parts (more than 15% of dots). Network technology screening. The size of FM screening dots is about 50 microns. After screening using Hybrid technology, the tips of dots with a diameter of only 50 microns will have relatively large wear during plate development and brushing, so they will also be lower than the average height of large dots, thus effectively Reduce the expansion of outlets.

In the 1%-10% highlight and 90%-99% dark areas, the special screening technology uses fixed-sized dots to achieve the reproduction of tone changes by changing the density of the dots; while in the 10%-90% The mid-tone reproduces the tone by changing the dot size like AM screening, which is called MaxTone. Originally tailored for flexo printing, the technology can now be used with any printing process. Kodak launched MaxTone screening technology, which allows users to define a micron-level minimum mesh dot size, and allows the screening engine to remove mesh dots in a random manner while ensuring that each dot is larger than the specified dot, so as to Maintaining the integrity of the entire tone so that highlights can be reproduced very well is HyperFlex technology, and MaxTone is currently an option for the Prinergy Packaging Edition workflow.

In addition, in terms of pre-press trapping processing, some improvements can be made when using the CTP plate making method. Leak trapping is mainly a process designed to compensate for the registration error of the printing press, but leak trapping also brings another undesirable result, that is, it will change the original design plan in small local areas. For example: if there is 0.15mm overprinting at the junction of the magenta block and the blue block, a purple line with a width close to 0.15mm will be produced where the two color blocks are adjacent, which is not acceptable to customers for some products with higher requirements. accept. In the CTP process, we can take advantage of the large slope of the CTP printing plate support base and the clear edges of the printing lines to adjust the thickness of the registration lines of the entire set of color plates. That is, the registration lines of the CTP plate will be changed from those commonly used in traditional printing plates. 0.1mm is improved to 0.05~0.07mm, and the overprint in the job can be adjusted accordingly to about 0.07~0.1mm.

With the digitization of the prepress field and the improvement of flexographic CTP technology, as well as the continuous development of mechanical roller precision and laser technology, sleeve technology in the field of flexographic plate making is gradually becoming mature. Sleeve technology is essentially an extension of CTP technology in flexographic printing. If the printing plate is made on the sleeve, the flexographic plate can be produced on the printing press. And using this method can achieve accurate positioning of the laser beam, achieve good overprinting and continuous seamless printing, thereby effectively saving time and a large amount of tube paper.