Paper Gift Pack color management and ink application

Paper Gift Pack color management and ink application

 

Color box packaging products often appear in the production of color recovery problems, such as neutral gray color, and then affect the quality of the product, in addition to the equipment itself, production personnel

In addition to the problems existing in the skill level, the key problem is that the enterprise has not been able to carry out effective color management and reasonable use of ink.

 

Color management is to manage people's sense of color, the purpose is to complete the conversion between the different colors in the entire image reproduction process, to ensure that the image color from

The appearance of the input display to the output display can match, and the final arrival of the original and replica color and consistent.

 

Image reproduction needs to go through multiple stages of image acquisition, processing, color separation, printing and so on. At each stage, the color information will be colored according to the equipment used at that time

Facts and color description features are displayed. Inconsistent scanning and display equipment will have inconsistent color display for the same manuscript. Other, the use of RGB three color color display

The color expression ability between the four-color printing ink is not good, and the application of the RGB data into CMYK is also lack of consistency, and the use of unsuitable paper and oil

Ink, the print is not the same.

Therefore, it is necessary to control the color recovery on all kinds of equipment and media in the production system through color management skills.

 

Color management content

 

Setting up the color Profile file of the device is the middle of the color management. The profile file contains the representative color characteristics of each device, such as the characteristic curve of chroma

The color management system uses these representative color characteristics to complete the matching and conversion of the color space of each device.

 

Color management must follow a series of polite processes to achieve the desired results. Color management is divided into three methods, referred to as "3C".

That is, Calibration, Characterization and Conversion.

 

Calibration: In order to guarantee the immutability, reliability and sustainability in the process of color information transmission, it is required to calibrate the input, display and output devices to guarantee them

In the form of standard obligations. Input correction includes the correction of brightness, contrast, and noise field of the scanner. To guarantee that a copy of the original copy is consistent, no matter when it is scanned,

They should all get the same image data.

 

By setting the brightness, contrast, color temperature of the display and the Gamma value of the whole display system, it can accurately display color. Output calibration and collection printer,

Phototypesetter, printing machine and proofing machine, after the correction of their characteristics, so that the equipment can be in accordance with the standard characteristics of the factory output.

 

Characterization: The process of characterization is to record the characteristics of all equipment after correction. These feature description files are from the device color space to the standard device independent color

Space (PCS) to transform the bridge.

 

Conversion: Based on the calibration of the system equipment, the use of equipment description files, with the standard device-independent color space as the prologue, the completion of the color space between the equipment

The exact transformation of. Because the gamut of the output device is narrower than the gamut of the original manuscript, scanner, and monitor, it is necessary to shorten the gamut during color conversion, and the gamut is shortened

In ICC peace talks, there are four methods: absolute chromaticity method, relative chromaticity method, bulge saturation method and sense method.

Implementation of color management

 

Shallowly speaking, about a packaging and printing enterprise to do a good job in color management, the need for a standard condition light source; High-quality color feature file generation; Raise the older generation

Color management system; Standard measuring and testing instruments; Standard color target; Standard printing management; Standard remote digital proofing color management; Standard scan recovery

Color management of digital camera; Standard monitor calibration and screen soft proofing. In the specific implementation process of color management, the following aspects should be done well:

Careful printing

The standardization, standardization and data production management of each process in the whole process is the premise and basis for the use of ICC color management.

Enterprises should strictly formulate quality standards for fine products, standards for paper, ink and other raw and auxiliary materials and equipment, standards for measuring instruments and condition light sources, and formulate standards

Quasi management documents, etc., and requires everyone strictly in accordance with the standards of implementation. Monitors, soft proofing, printer ICC files, printing machine parameters to be standardized, and in the standard and

Quantization is carried out in the specification, and the quality data can be guaranteed by testing methods in all the local expressions that can be expressed by data. They complement each other and depend on each other

Save, and then guarantee constant high quality, high efficiency production.

 

Pre-press image preparation skill is the basis and key link of printing reproduction quality. The display should be professional, the scanning of the original manuscript and the arrangement of the digital original manuscript should be consistent with the copy quality of the four

The basic criteria (gray balance, tone reproduction, color correction, sharpness enhancement) are used to guide the obligations, and the parameters of the four criteria are regulated by the implementation. Scan the file to complete, to the

Make adjustments and artistic processing for the defects of the non-suitable manuscript, so that the print level is more fat, and the results are better than the original manuscript. About remote printing enterprises, remote digital proofing

Profile file management to ensure that the color of digital proofs is consistent between the two locations.

 

Choice of color management system

At that time, there were many color management systems on the market, such as Adobe Photoshop color management system, Apple's ColorSync color management system, Kodak color management

Systems, etc. The color management system for the color management of the equipment is different and has its own good part, so the enterprise must first determine which equipment is needed

To obtain a consistent color, so that the selection.

 

Secondly, the self-description file in the color management system should be determined, and whether the self-description file can be supported in the open system. If it is a closed system, it must be by the factory

Set up a painting document, how the need to determine whether can afford to set up a painting document required cost. It should be aimed at the enterprise's own situation, the system's availability and equipment support

Ability, scalability, compatibility and ease of use and other functions are compared and tested. When testing, you can use the same colorful manuscript to observe which system is in specific operation

Under the condition, can obtain the most consistent results with the original manuscript.

 

Effective color management is the guarantee of the quality of the entire copy, but the final product is obtained through the ink. Ink as one of the five basic elements of printing, printing

Brush process and quality have primary impact on results. Accurate and reasonable use and distribution of ink is the key to ensure the accurate recovery of color.

The application of Chinese ink

The composition and function of ink: water-based ink is made of water-soluble resin, advanced pigments, solvents and additives. Its hue depends on the nature of the pigment, shallow requirements

The pigment has brilliant brilliance, stable coloring and concealing power, superior patience and high dispersion. In order to obtain the superior printing suitability of ink, it is often necessary to meet the requirements

Use all kinds of ink additives to adjust the movement of ink, monotonicity and viscosity. The selection of ink quality elements, improper use, will bring a series of quality problems

When purchasing and using, we should pay attention to analysis, distinguish the appearance of its quarrel, and make adjustments according to the situation to ensure its excellent printing suitability.

 

In printing, a certain viscosity of ink is a prerequisite for the normal transfer and transfer of ink. Therefore, the viscosity of high-grade ink is controlled in 20±5 seconds or so

The difference in viscosity will constitute the depth of the printing color. In the process of theoretical production, according to the compatibility of the substrate and temperature, the PH value of the machine can be adjusted or controlled at 8.0

Between ~ 9.5.

 

Ink distribution: The first assumption of ink distribution refers to the color of the ink. In the printing of packaging products, the color used in ink is mainly spot color field flat, which reaches the vision

And the double consequences of anti-counterfeiting.

 

These unsuitable spot colors can not be overprinted by green, product, yellow and black four colors, and often can not find the original ink directly used, and must be produced by skilled personnel

The original ink is obtained by disproportionate distribution.

 

The color distribution of ink is based on the principle of subtractive method, that is, any color can be used in the disproportionate mixing of the three primary colors, and think about its hue and lightness

And saturation. Color matching should be based on the theory of printing technology, ink layer thickness, printing substrate and other premises to choose the ink used, and consider the hue of the ink itself

, gloss, coloring power, concealing power and other elements.

 

Color matching process

 

Analyze the color of the original manuscript: Color matching is carried out for the color sample of the original manuscript. In order to increase the blindness of color matching, it is necessary to analyze the color of the original manuscript first to determine the demand source

The hue and proportion of the ink. The first assumption of the analysis of the manuscript was that the instrument was used to measure the color and the human eye colorimetry. The use of printing chromatography to determine the proportion of three primary color ink is relatively simple

Can be calculated according to the percentage of the primary color dot area in the chromatogram.

 

Color matching: according to the ratio calculated, first weigh a small amount of original color ink for distribution. Pay attention to the ink color and the original color from time to time comparison, when the two colors are close, desirable tone

The ink in the scraping paper line scraping sample contrast, repeat, until the two colors are completely consistent. When color matching, the ink should be even, and the thinner the ink layer, the better, in order to ensure color sample color

For accuracy, the paper should be the same as the paper used for printing. Brightness and saturation are adjusted by adding white and black ink. When the demand participates in white and black ink,

 

Should pay special attention to the accuracy of weighing.

 

After the ink to be distributed arrives at the requirements of the original manuscript, the bulk ink can be distributed according to the proportion. The amount of ink used in a batch of live parts is determined by the type of paper specifications and drawings

Like the area, the number of prints and the amount of loss to determine, and the principle of more not less.

 

Record: After the preparation is completed, the matching ratio of various colors of ink, ink, drying oil, ink model, quantity, manufacturer and other information will be published in detail, which is convenient for the future

As a reference when blending ink.

 

Other painful items: in the analysis of the original manuscript, color, it is best to carry out in the standard light source or close to the light source, but also pay attention to the ink film after monotonous color,

To add visual error. Try to use close to the original color ink or other single color ink when matching color, color using too much ink, its brightness and saturation is worse

After the impact of printing consequences. Therefore, the less the number of ink color, the better, the best choice of a consistent manufacturer of ink products.

 

When toning, we should fully inquire about the daily printing speed and printing pressure of the factory equipment, and control the ink viscosity. The color of the printed product printed at the wrong printing speed and pressure

Depth will be inconsistent, so at low speed distribution of good ink will need to be printed speed to the normal speed to check with the original again, so as to avoid the existence of color difference, constitute a mess.

 

After the ink is adjusted, it is assumed that the color sample printed on the machine and the original manuscript should be corrected in time. When changing color, the ink bucket and ink roller should be cleaned to avoid cleaning

Impure and attack color cast. The residual special color ink after printing can still be distributed according to the hue of the new manuscript, but often the saturation is gray, especially the residual that is taken back from the ink dou

The ink may have been emulsified or printed with modifications.