On the core technology of Cigar Paper Boxes digital printing and digital printing

On the core technology of Cigar Paper Boxes digital printing and digital printing

 

With the development of technology and the popularization of computer and Internet technology, we believe that the digital upsurge has been set off in the printing industry, which is a traditional service industry, and through the development of CTP technology, which is the core technology in the digital process, the digital management of the whole printing process has been realized. (The full name of CTP is Computer to Plate, that is, computer direct plate system).

 

In the traditional printing process, processes (1) and (2) are digital, that is, the formation from electronic document to film film is digital, so film film to PS plate and printing press to form the finished product of the series of processes is non-digital. When the film is formed into PS plate by printing machine or printing machine, the data of film film will be lost in the process of vacuum adsorption and the flushing process of printing machine.

 

Therefore, traditional printing can only reach the printing accuracy of 150 lines, and the dot reproduction can only reach 5% ~ 95% reproduction, that is, in electronic documents or film can not reproduce less than 5% of the dot. Then, after the traditional printing process, the final dot displayed on the printed product is either 0% (that is, printing is blank) or more than 5%. As you can see, this process cannot be evaluated digitally, that is to say, it cannot be managed digitally in the actual production process. In Figure 1 above, we can see that this is what is meant by the notation "digital samples can be made, but cannot be matched" under the electronic document. The customer gives the printing house an electronic document to print the finished product, in the traditional printing process, how to achieve the quality inspection? After the printing plant receives the electronic document, it will print out the digital sample to the customer to confirm the format. After the text is correct, it will carry out laser phototypesetting.

 

Before making the PS plate and printing on the machine, the customer will go to the printing plant workshop to communicate with the customer about whether the ink color is suitable, and finally the customer will check the finished product according to the sample. This is the traditional printing process. From the perspective of the whole process, it is non-digital, that is to say, there are many processes that have no absolute and unique standard and rely on human experience to implement. This traditional non-digital process is also the printing production process implemented by most printing companies in China. With the rapid development of CTP technology and equipment, with the market share of CtP technology in Europe and the United States has reached more than 80%, but also with the domestic printing enterprises began to use CTP technology, making CtP technology and equipment known as China's printing enterprises in the past two years of technical transformation of the hot spot. Here we take a look at the characteristics of digital printing processes using CTP technology.

 

In this process, the use of CTP as the core of the whole process, so that the traditional printing process to achieve full digital printing.

 

The first is CTP, which is derived from English Computer to Plate. The original meaning is computer direct platemaking machine, that is, CTP in the narrow sense refers to a machine can directly generate a printed version from electronic documents, and eliminate the traditional platemaking process of electronic documents to produce film. Two processes in which film is produced by a printer. Nowadays, with the development of printing technology, CTP stands for computer direct plate making system. Note that the current CTP refers to a system that includes not only the equipment that directly generates the printing, but also the pre-press software, the interface software that connects to the printing press, etc. According to Germany's Heidelberg Printing Machinery AG, the world's largest supplier of printing systems, "the CTP is neither hardware nor software, but a system. And we think it's a core system in the printing process. It's part of printing."

The unexposed CTP plate with lining paper is placed into the CTP host, and the lining paper is removed from the CTP plate through the thin lining paper separation system. Pack the lining paper in the lining bag. At this time, the device will first position and punch holes on the plate, and then install the CTP plate with the positioning and punching holes on the plate cylinder. The CTP plate fixed on the plate cylinder will run at a high speed through the rotating unit. At this time, the laser system starts to expose the CTP plate. Then through the connecting bridge automatically sent to the line plate punching machine to complete the washing, that is, to complete the printing press printing CTP plate.

 

How to expose, exposure intensity, exposure time, etc. are controlled by software. Let's look at the software part of the CTP system. The software section of CTP covers a wide range of content. It contains:

 

1. Image raster Processor RIP - Industry standard for generating printing and image processing software. Adobe Postscript 3 and. File in PDF format.

2. PDF file job editing process - processing various documents according to production requirements. Including trapping, color management, plate, a variety of screening schemes, including amplitude modulation screening technology, frequency modulation screening technology mixed screening technology, ultra fine screening technology, 25μm screening technology, large software, output production data connection.

 

3. Digital proofing software -- based on the image raster processor RIP, DF file converts customers' electronic documents through the setting of digital proofing, and completes the digital printing sample through the digital proofing machine, which will complete the signature of the end user and eventually become the acceptance standard of the printed product.

 

4. CTP and connecting interface software - It is known that most of the imported printing and factory have CTP and printing and connecting interface hardware as a standard configuration, so the configuration of CTP and printing press connecting interface software. It can realize the digital connection of printing and CTP, and realize the digitalization of the whole process of printing.

 

Next, we will elaborate on the whole production and processing process of the whole digital printing process described in Figure 2.

First of all, we receive digital manuscripts or electronic files from our clients. This digital manuscript is sent to CTP to form PDF files and formats that meet customer requirements through the image raster processor RIP and PDF file editing process. At this time, the CTP will transfer the file to the digital proof machine through the digital proof software, and make the printed product required by the customer into a digital sample and give it to the customer for sample signing. This sample will be used as production standard.

 

After signing samples, the PDFS processed by the CTP software are sent to the CTP device. The CTP controlled laser exposure device directly exposes the CTP version, forms the CTP version by punching the plate, and gives the printing press to be directly on the printing press. When the CTP plate is delivered to the printing press, the CTP system connects the printing press with the interface software of CTP. The CTP system directly transmits the data of CTP production to the connected printing press, and sends all kinds of data of the printing plate, including the ink data of each region and the data of moistening liquid, directly to the control system of the printing press. The control system of the printing press directly sets this data to the ink supply system and plate embellishment system of the printing press to complete the setting of the printing press, so as to ensure that the color of the printed product is consistent with the digital manuscript, so as to realize the "CTP connected with the printing press to realize automatic ink supply" in figure 2.

 

Finally, let's analyze how to achieve the most important and core republic in the digital printing process, the last arrow of the figure ② "achieve 100% match between the printed product and the digital proofing proof". After configuring the CTP system, the customer needs to debug the CTP system. This debugging strictly requires personnel allocation to complete. In addition to CTP line CTP system personnel, also need printing press debugging personnel, so the printing process is more complex, printing paper printing ink, printing and use of consumables such as rubber blanket, moistening liquid, etc. The rate of dot change is also different for each press. Therefore, the printing press debugging personnel need to form a dot change curve according to a certain ink paper, blanket, moistening liquid, etc., and this curve needs to be given to the CTP system debugging personnel feedback to the CTP system as a correction curve. With CTP system debugging personnel obtained CTP linear curve, digital prototyping set curve.

 

Comprehensive and form a new comprehensive curve, used to guide the CTP system to generate CTP version, so as to achieve the printed product and digital proof 100% consistent. To put it simply, the electronic documents submitted by customers at some point are 20% of the points. So the proof of the digital prototype is 20% of the dot, the finished product is 20% of the dot. The PDF file in the CtP system may not be 20% dot, and the CTP version may not be 20% dot. Because of the use of CTP system, the digital process of the whole printing process is realized, so the dot reproduction can achieve 10% ~ 99%. Because the intermediate process is completed within the CTP system, there is no process transfer process. At the same time, the CTP system allows printing resolution up to 250 lines or even 300 lines, thanks to the laser-generated plate system. Therefore, compared with the traditional printing process, it improves the printing quality and efficiency. In addition, the CTP system and printing process described in this article refer to the most widely used offset printing process. Other printing methods, such as gravure printing, flexographic printing, screen printing principle is roughly similar, there is also a special CTP system can be used.

 

To sum up, the core of digital printing process is CTP system. The use of CTP can effectively improve the quality of printing products, efficiency, reduce the management cost and dependence on technical personnel, so as to realize the digital management of the entire printing enterprise.