The Computer-to-plate(CTP) Definition
Computer-to-plate digitalized the plate-making processes with modern imaging technology and is well known as CTP. It uses laser beams to image directly onto a printing plate, then transfer to the plate which is called computer-to-film (CTF), similar to darkroom photography. This improvement in technology (CTP) eliminates complicated film processes and increases productivity in the printing industry.
Different types of plates in the CTP system
There are four types of CTP on the market:
- Thermal
- Silver
- Photopolymerization
- Treatment-free
Thermal CTP plate-making technology is the most mature, stable, and best effect of plate-making technology. Thermal CTP plate: it now mainly has two types of thermal fusion and thermal crosslinking.
Thermal CTP characteristics
Thermal CTP plate on the natural light sensitivity is very low infrared laser exposure, so it can be operated under the conditions of a bright room.
The thermal plate to generate images, must achieve the initial thermal energy threshold, and the heat energy is higher than the initial threshold will not change the dot shape, is the only technology that can control predicted results, easy to control the quality, print quality is stable, and the plate can be extended to six months after exposure after enhancement, will not have any effect on the quality of plate material.
The dot reproducibility of thermal plate material is good, the resolution is high and the dot edge is sharp and clear, and it is easy to achieve ink balance when printing, with good printing suitability, and the plate after baking can reach more than 1 million printing.
The CTP benefits (compared with CTF)
- CTP has multiple advantages compared to other conventional printing processes.
- Remove the film generation and chemical usage layer to save material costs.
- Accelerate the processing time rather than using conventional plate-making which requires film workflow to save more time.
- An easier, safer, efficient way of storing digital images.
- Print quality improves, the potential dot gain reduction allows denser inks to be used in the press which also owns better color saturation.
- A copy change is easier with CTP as the change is based on a digital file which imaging onto a plate rather than reproducing new films.
Common plate in CTP system
In the offset printing field, we might hear prepress requires printing plates for processing. In the CTP market, violet and thermal are currently the major ones. You can easily find these CTP plates in Kodak, Agfa, Fujifilm, and PlatesChina. Most of the plates are compatible with reputable platesetters from Heidelberg, Screen, Agfa, Kodak, Amsky, CRON and so on.
