Custom Paper Jewelry Boxes printing color management and printing production optimization

Custom Paper Jewelry Boxes printing color management and printing production optimization

The optimization of printing production includes: equipment condition optimization and production process optimization. Equipment condition optimization refers to making the equipment run in a stable and optimal state and give full play to the efficiency of the equipment by adjusting the setting of various environmental and material factors in the printing production and the equipment. Production process optimization refers to the minimization and automation of the printing process. From the perspective of color control, it involves the pre-press and printing process. Figure 2 shows the printing color management process after production optimization.

 

1. Equipment condition optimization

 

Equipment state optimization is the coordination and unification of printing environment, printing materials and hardware equipment. It mainly includes the optimization of printing press and prepress equipment. The optimization objects of prepress equipment include scanners, computers, monitors, laser phototypesetters, CTP and digital prototyping machines. The optimization method is to stabilize the printing process parameters through datagram and normalization, as follows:

 

1) The normalization and standardization of the printing environment

 

Printing environment mainly refers to the temperature, humidity and lighting conditions before printing and printing workshop. The standardization and standardization of printing environment should be based on national or international printing industry standards. The temperature and relative humidity of the workshop should be kept in the best condition to minimize static electricity, dust, paper wool and other pollutants on the film, printing plate and equipment, maintain the stability of the paper, and reduce the problem of fountain, printing plate and ink as much as possible. The standardization of lighting conditions needs to establish a standard observation environment, such as the walls of the workshop to maintain neutral gray, and the use of D65 or D50 standard light sources and light boxes to ensure the stability and consistency of the observation of the original image and printing proof.

 

2) Standardization of printing materials

 

The STANDARDIZATION of printing materials includes the standardization of material purchase, material testing and the establishment of performance data files, and it is best to implement relevant quality standards (such as ISO9002 standard system). Printing enterprises should formulate standards for material selection and purchase, inspect and test raw materials, determine the performance of materials, the matching between materials and the compatibility of materials and equipment, and establish material data files to achieve the standardized management of printing materials. The main printing materials are: ink, printing plate, blanket, roller, paper and fountain solution.

 

3) Calibration and normalization of display

 

In the prepress environment, the display has high requirements, and the color characteristics of the display are affected by many factors such as lighting environment and display brightness. The most ideal lighting environment of the display requires the window to cover the heavy dark curtain to avoid the interference of the external light source and prevent the influence of the ambient light on the color perception of the human eye. In addition, the display itself also needs to be calibrated before use. Although the display has passed the manufacturer's debugging and calibration at the factory, no two displays are exactly the same, and the color reproduction performance of the display will change over time. The screen corrector can be used to correct the display, and the correction items are mainly brightness, contrast, Gamma value, fluorescent agent type, etc.

 

4) Calibration and standardization of scanner

 

Most scanners self-calibrate at startup, and those with auto-calibration will do so with a built-in reference. For a scanner that does not have an automatic calibration function, it must be calibrated. Scanners can generally be calibrated using the IT8 color scale.

 

5) Standardization of film output process

 

The standardization of film output process is to ensure the quality of film output. Optimization should start at the press and go back to the prepress system and color separation. Printing press optimization must set the standard of each part of the printing press, know what problems may occur in printing, evaluate the quality and compatibility of printing materials, and finally determine the optimal working state of the printing press, and stabilize this state.

 

It includes the selection of film, the test of film performance, the control of developer temperature and concentration, and the establishment of film output data files. There are two main factors in the quality of film output: film density and the linearization control of film recording dot. Film density generally requires the lowest density value is not more than 0.07, the highest density is not less than 3.5. Dot linearization function can be set in RIP, the purpose is to ensure that the dot can be correctly recorded on the film.

 

6) The standardization of the traditional printing process

 

The standardization of the traditional printing process reflects the plate-making concept with printing as the focus. High quality, high efficiency and standard printing make a great contribution to improving the efficiency of the whole printing production. The standardization of the printing process includes: keeping the printing workshop clean and dust-free, meeting the humidity requirements, ensuring the stable performance of the printing machine, mastering the correct exposure and development time, and making good use of various testing tools.

 

7)CTP plate-making standardization

 

CTP plate shortens the printing production cycle and improves the printing efficiency. Compared with the traditional plate-making process, CTP has the advantages of high timeliness, good dot quality, and large range of replicable stage adjustment levels. The standardization of TP plate-making should refer to the traditional plate-making process parameters and establish a good digital production environment.

 

8) Standardization of digital proofing

 

Digital proofing is the process of using digital originals to directly output printed proofs, the main purpose is to achieve customers to see the sample signature sample. Therefore, printing enterprises generally take customer satisfaction as the standard of proofing. However, this kind of non-professional subjective evaluation inevitably leads to many problems. For example, when the printed matter cannot achieve the color effect of the proof, there will be a contradiction between the customer and the enterprise. However, when the printed matter is matched with the proof sheet, the quality of the proof sheet cannot be guaranteed next time because the enterprise does not have a standard for quantitatively measuring the proof sheet. In order to solve these problems, printing enterprises must formulate digital proofing standardization documents to standardize digital proofing. The standardization of digital proofing includes choosing suitable digital printer and matching paper and ink, collecting data based on printing to realize the gamut of digital proofing machine simulation printing, regular detection and maintenance of digital proofing system, etc.

 

9) Standardization of printing presses

 

The purpose of press normalization is to find the best condition of the press to match the printed material, determine the maximum ink density and dot expansion characteristics of the press, and this process must be completed through a series of tests. The setting of each printing part of the printing machine should be carried out according to the instructions of the printing machine manufacturer, including the setting of the ink roller and water roller, the setting of the compression amount of the printing blanket, the correctness of the plate and the blanket lining, the cleaning and lubrication of the paper feed device of the printing machine, the cleaning and lubrication of the paper transfer and overprinting system and the paper receiving device, etc. On this basis, the performance matching test between the material and the printing press is carried out to determine the optimal state of the printing press, and the data is made.

 

2. Production process optimization

 

It mainly includes two aspects: optimizing ink presetting and optimizing color restoration process control.

 

(1) Optimize the ink presetting

 

Ink presetting refers to the determination of ink preset value of printing machine. There are three methods of ink presetting: human experience setting, plate scanning setting, and directly generating ink presetting data from the prepress link. The accuracy and efficiency of human experience setting mainly depend on the printing production personnel. It is difficult to datafize and standardize the experience, and it takes a long time to form the experience. Plate scanning setting is to obtain ink preset data by scanning and analyzing the graphic information of yellow, magenta, cyan and black plates by plate scanner, and then transmit the preset data to the control center of the printing machine through storage devices or network, and finally reflect on the printing machine. Its accuracy and efficiency depend on the precision of the plate scanner, the speed of scanning and the speed of data transmission. The third method is to directly generate the ink preset data from the pre-press link. The system to generate the ink preset data is the digital workflow. In the digital workflow, the preset data is transferred to the printing machine control center through the storage or network in PPF (PrintProductionFormat) file, and finally reflected on the printing machine, as shown in Figure 3. Compared with the three methods, the third method is faster, more stable, easier to achieve datafication and standardization, and can better optimize the printing production process.

 

(2) Optimize the control of color restoration process

 

The control of color reproduction process is through some on-line printing quality monitoring system to collect and analyze the printing image in real time, and feed back the results to the prepress link and the printing console for timely correction. Optimizing the control of color restoration process is mainly to establish an effective automatic color restoration control system, build a communication bridge between pre-press and printing, and improve the effective running time of the printing press.