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During the process of printing, the relation between ink amount and the reproduction of tones is focused. There are errors in the results, because the solid density is the subject while there are some difficulties in controlling of ink amount. If it is done in the real production and fine control of ink, the effect of ink amount on the tone replication of the different dot area rate are analyzed, it will be better to provide the basis of printing quality. The experiments were done in the printing machine of Heidelberg SM 52. The ink amount is increased by 5% once to print for many times. According to these samples, this paper is got the results of density of different dot to different ink amount, dot gain and contrast, the laws and the relationship between ink amount change and the tone replication. The research results show that there are different laws between ink amount and dot density , ink amount and dot gains. The solid density is determined by analysis of contrast.

Neugebauer equations are the basic formula in color printing. However, this is a theoretical model. If the printing conditions and complexity of overprinting are not considered, the result obtained by Neugebauer equations will not be very accurate. The Neugebauer equations need to be corrected in practice. There are some methods such as Yule-Nielson correction, Cellular correction, dot gain correction and so on. In order to improve the precision and analyze the cause of errors of Neugebauer equations, a model using a spectral dot gain correction is given in the paper. The dot gain is generally a function of wavelength. Dot gain in each wavelength of a primary is treated in calculating the Demichel equations, and the corrected dot area is used as weighting factors in two color overprint and three color overprint process. The experiment and calculation show that this method can improve the precision of the equations a lot.

Dot gain divides into physical and optical dot gain. These two parts constitute the comprehensive dot gain in the process of printing. Ink spreading on the surface of paper is used for the analysis of physical dot gain and light scattering function model is used for optical dot gain. Trace the dots on the CTP plate and offset printing proof to analyze the influence of image micro-parameters caused by dot gain. Physical and optical dot gain are quantized to research the correlation between dot gain and shape of dot. It shows that: optical dot gain of AM dot accounts for a larger proportion; dot gain of all types has no relation with shape of dot. Besides, physical dot gain of FM dot accounts for a larger proportion than optical dot gain.

Y_N model-based printer forward characterization, considering the influence of the physical dot gain and optical dot gain, it needs to determine the effective ink dot percentages and the factor n of Yule-Nielson model through single-channel ink limit and nonlinear optimal method. Based on the foregoing, we can determinate the dot transfer function of multicolor printer. Before Y_N model formula factor n and effective dot percentage being determined, it needs to get the sample by printing each primary color inks foot ladder. However, transferring ink to the substrate occurs obvious physical dot gain issues, while the paper absorbing ink ability is limited, so firstly implementing single channel ink quantity control for printer becomes particularly important. Considering the problem of the optical dot gain resulting model accuracy misfit, Y_N model introduces a parameter factor n to correction.

IIndoor photo has been widely used in products of shopping malls publicity, light box advertising, wedding photography, posters, engineering and landscape effect picture, digital photo album, art photo, antiquing canvas and window advertising. PP synthetic paper which was the most common indoor photo materials was selected as the research object, and it was printed by the photo printing machine. A series of experiments were carried out according to its printability. The main parameters of PP synthetic paper such as solid density, dot gain and relative contrast were tested, which provided a theoretical and practical basis for digitization of indoor photo.

Digital printing can print directly the information which will be printed on the package box by digital print machine and internet or computer, which removes the procession of color separation, makeup, plate-making in the traditional printing. The digital print can print any number package box at any time and at any place, which can realize the variable data printing, and which has a price advantage in the short version printing. Therefore, digital printing is a good method for personalized packaging printing.In digital printing, color control is important for print quality detection. In this paper the dot area percentage of cyan, magenta, yellow ink can be predicted by measuring the color’s spectral reflectance in order to control the ink’s amount in digital print and realize the color’s precise control of cyan, magenta, yellow. In the prediction model of three color ink’s dot percentage, the characteristic of spectral reflectance curves for the various color ink is analyzed, and each ink’s high reflectivity and low reflectivity which is high correlation with the dot percentage is chosen and is calculated by normalization method in order to get each ink’s dot area percentage’ prediction model. At last by measuring the paper’s spectral reflectance and the using normalization method, paper’s color can be described, and the effect of paper on monochrome color ink’s dot area percentage can be analyzed. The research has important significance for packing box’s digital printing’s color high-fidelity reproduction.

In order to research the relationship between ink permeability and dot gain of different paper, four kinds of coated paper and two kinds of printing paper were chosen. Ink marks method was used to measure ink permeability of four kinds of coated paper and two kinds of common printing paper. After the ink marks were printed on each of the six kinds of paper, the length of them were measured, then the reciprocal of the ink marks length was multiplied by 1000 to obtain the value of the ink permeability. Inkjet printer was also used to print yellow GATF step-wedge simulating offset printing on the six kinds of paper, then using an optical densitometer to measure the dot gain. Conclusion shows that non-coated paper is higher in permeability than coated paper, which results in high percentage of dot gain.

Concentric dot is formed by dividing round AM dot into thin concentric rings, which has not only the shape characteristic of AM and FM dots, but also the features and advantages of the two dots. The Concentric Screening is a new halftone screening technology which breaks through the traditional model of reproduction image information by solid dot. To use concentric screening technology in offset printing, the first step is running single color print test to determine concentric screening parameters for the given printing condition. which is unique to concentric screening compare with solid dot printing. Through analyzing and evaluating the printing characteristics of single color print test, the paper provides the method to determine screening parameters such as screening rulings、CTP precision、the width of Ring and Space; Designing and running the four color test based on the first step is aimed to study the reproduction characteristic of concentric dot about gamut、definition、chroma, tone, compared with solid dot. The research shows that the parameters of concentric screening should be determined according to the specific production condition in offset printing. Concentric screening can obtain high saturation and present large color gamut. Also, concentric screening is suitable for high-quality products, which can accept high screen rulings and high-definition. This paper contains experimental study on the correlation between concentric screening parameters and color reproduction. The basis for evaluating concentric screening parameters is offered, and a comprehensive evaluation of its reproduction characteristics is done. This study provides a theoretical basis for the application of the concentric screening technology in offset printing.

Yule-Nielsen neugebauer spectrum(YNSN) model can describe the relation between dot area and spectrum reflectance, which can calculate the effective dot area. The modified index in the model still can’t be determined. The reciprocal of paper’s spectral reflectance at the range of visible light is adopted as the modified index in YNSN model in order to reduce the optical dot gain. By experiment, the modified YNSN mode can be used to calculate the effective dot area of light color. The research has a certain significance for controlling and testing printing color.

Concentric dot is a new shape of ink dot, which subdivides dot of AM screening into ring and space. Concentric dot has morphological characteristics and reproduction characteristics of AM dots and FM dots, also has excellent color reproduction characteristics. Compared with traditional solid dot, high saturation of concentric dot has been proven. However, the mechanism of this phenomenon is rarely reported. Taking AM dots as reference, this paper try to explain the high saturation of concentric dot theoretically from several aspects, and aims to reveal the mechanism of the color reproduction characteristics of concentric dots. Due to the low amount of ink, the surface of concentric dots is smoother, and achieves better reproduction of color. The distribution characteristics of ring and space result in dot gain both inside and outside of concentric dots, which have a positive impact on the color reproduction. Establishing the relationship of optical dot area and saturation, the difference of color reproduction characteristics between concentric dots and AM dots can be analyzed as the result of the different microstructure of two dots. Using the improved Clapper-Yule model and the law of Lambert-Beer, the conclusion above can be analyzed theoretically. On this basis, experiments are designed and carried out to prove the correctness of theoretical analysis. According to the research, several conclusions are made. The conclusions can be list as follow: different saturations of concentric dots and AM dots lead to different color reproduction, when optical dot area stays the same; different saturations of concentric dots and AM dots is mainly caused by the microstructures of the tow dots; Under the same condition of incident light, concentric dots of monochrome ink reflect more of the visible spectrum than AM dots after absorption, which reasonably explains the high saturation of concentric dots. The study is to reveal the principle of color reproduction of concentric dots with high saturation, providing a theoretical basis for the application of concentric screening technology.

To expend the printed color gamut is the most important area for today’s print quality. Conventional wide gamut printing technologies utilize six or seven colors. However, these processes increase the complexity and the cost. Therefore, the four-color wide gamut inks are becoming the major development in Taiwan’s printing industry. This study is focused on the print performance study of the four-color wide gamut inks in the domestic market that are complied with the RoHS regulations. In this study Tung-Ming and K+E wide gamut process inks were tested for their print performance. The press control was to comply ISO12647-2 specifications. The test forms were printed on both type 1 and type 2 papers that specified in ISO12647-2. The normal process ink set was also printed to compare with those wide-gamut color ink sets. The result shows that the both wide-gamut ink sets have reached color gamut larger than the ISO12647-2. In this study shows that the domestic normal process ink set can comply the international standard, and the developing wide gamut ink also reach the standard. However, the color characteristics and printability have to test before using these wide gamut color ink sets. With the optimized process control and color management system, the four-color wide gamut inks can produce the best color result on paper.

Optical dot gain is the key point of halftone reconstruction study, and has always been a meaningful topic of theoretical study. The Yule–Nielsen formula is by far the most widely used research method of optical dot gain. However, solving the Yule–Nielsen parameter n remains a difficult problem. This paper disregards solving for the Yule–Nielsen parameter n, analyzes the light scattering and osmotic effect of halftone presswork, deduces the exact expressions of blank area of presswork, and determines the reflectivity of the dot part and halftone presswork according to the point spread function and probability method. Furthermore, this paper analyzes how the optical dot gain depends on the dot area coverage of presswork, ink layer transmittivity, and paper-based spectral reflectivity. In addition, a new algorithm model for optical dot gain is established. By employing the Clapper–Yule Model to calculate the spectral transmittance of printing ink and comparing it with the practical measured spectral reflectivity of the halftone presswork proof, the accuracy of the model established in this paper is fully verified.

The paper properties such as roughness, gloss, surface wettability and other factors have great influence on the dot reproduction attributes of presswork, and different paper factor has different effect weight on the dot reproduction. The main purpose of this paper is to provide a new method to analyze the influence of paper properties on the dot reproduction. The method is to apply the grey relational analysis to analyze the influence law and the effect weight of paper factors on the dot reproduction during inkjet printing, which could provide theoretical guidance for improving the printability of paper. The grey relational analysis is a multi-factor statistical analysis method, which is based on the sample data and the grey incidence of various factors and is used to describe the strength, size and the order of the relationship between the factors. In this experiment, five types of inkjet printing paper were used to test their printing performance, and then the dot gain data were dealt with by the grey relational analysis method. Results showed that paper properties had a great influence on ink setting. Ink drop diffused and deformed less and dot gain was small when paper had smooth surface. According to the correlation coefficient degree of paper properties which influence on the dot gain of inkjet printing, the sequence was whiteness, roughness, surface wettability and gloss. Whiteness and roughness could significantly influence dot gain, followed by surface wettability, and gloss with minimal impact. Experiment indicated that the grey relational analysis was a simple and effective tool to analyze the influence of paper properties on the dot reproduction of presswork.

This article discusses diversifying graphic design elements based on existing print reproduction principles and technology. The authors studied color processing techniques derived from print reproduction principles and assorted image elements derived from restrains in printing technology. The authors also discussed disassembling and restoring procedures during image transformation and reproduction to explain and explore the different styles and compositions of art forms that carry profound information. The visual impact coming from pixel’s form, arrangement, color, direction, and other factors is also delicately explained. Concurrently the authors examine the manipulation of technical parameters in the printing process and exploit the aesthetic value revealed. The focus is to elaborate upon artistic features achievable from dot gain, color overlapping, omitting, merging, and other aspects. The authors also explore innovative visual elements on the basis of existing developments in print reproduction principles, printing technology, and prepress design and they discover new channels for utilizing dots as a unique expressional element in graphic design. The ultimate goal is to show that print reproduction principles and technology are not only a means of reproducing images, but also dynamic and powerful tools for creative design.

In packaging market, Vacuum Plate of Aluminum by UV offset printing is light impediment effectively, moisture-proof, and forgery-proof and reaches the request of the green packaging production. Thus, the packaging of Vacuum Plate of Aluminum is used widely. This study was a true experimental research. The test form employed was the printing quality control strip from international printing specification. It was used to record and analyze the color variance between Vacuum Plate of Aluminum and Aluminum Foil with white board and no white board using UV Offset Printing. The study indicated the comparison of Tone Value Increased & the difference of Color Gamut Range among these three packaging materials via C, M, Y, K four colors tone value and RGB area testing, and results reveals that the tone value on the Vacuum Plate of Aluminum with white board increased most among these three materials; the dot gain percentage of the Vacuum Plate of Aluminum is less than 15% which with the highest stability than others. All signature findings are given in Fig.1 and Fig.2. These results are entirely consistent with research hypotheses.

Recently flexography develops faster and faster. The fine degree and the speed for making plate is asked to be higher. Flexographic cyrel digital imager (CDI) can meet the requirements. This article analyzes briefly to the parameters of making plate of CDI. The parameters for affecting the flexographic printing can be ensured. And the correct exposure time is made for making plate. Results show that the quality control is a systematic process. When printing different production, different screen lines, exposure parameters are adopted. By controlling the exposure time, the dot gain can be controlled effectively.

The global trend of digitization has totally varied the printing production processes. Among different printing technologies, digital ultraviolet (UV) ink-jet printing has strengths of easy to dry, printing on unsmooth surface, easy to print with different substrates and lower cost, and hence was commonly adopted by different industries. This study was to evaluate the print quality and weathering resistance of UV ink-jet printing on glass. The UV inks, from companies of AGFA and Anderson companies, and Primer adhesive and white ink from a domestic company were adopted in this study. Four types Primer were applied, i.e. without Primer, one layer of Primer, three layers of Primer, and five layers of Primer, before the print test target was printed. Two types of inks from AGFA and Anderson were used by a UV ink-jet printer to print out the test target. A spectrophotometer was used to measure the test charts, and the print quality was analyzed in terms of color contrast, solid ink density, ink trapping, dot gain or tonal value increment, gray level, etc. The experiment showed that test targets printed with two types of inks had no significant difference both on printability and print quality. However, the Anderson ink had slightly better print quality, weathering resistance, wear resistance, and adhesion compared to those of AGFA’s. Glass printed with Primer and white ink layers in advance had better printability and color quality in the experiment. Overall, UV ink-jet printing on glass had excellent printability and color performance. The results of this study can be referred by industries.

To make the dot gain compensation curve more precise, this paper analyzes the methods already used and then propose a new method. We implement this new method and the old ones respectively through MATLAB, and get their dot gain compensation curves. At the same time, the average error and variance were counted to test their precision. The results show that the new method can apparently improve the precision and reduce the error. The average error of the normal method is 2.96% while it is reduce to 1.56% by the new method.

Ink-jet light-box cloth has been widely used in municipal engineering, supermarket, exhibition, hotel and other places, and played an indispensable role of advertising and decoration. There have been no unified parameters and standards for printing quality evaluation of ink-jet light-box cloth. To solve this problem, a group of researches were carried out according to its printability, which selected light-box cloth printed by inkjet. The parameters such as solid density, dot gain, relative contrast of the light-box cloth were tested and analyzed. Based on the results, the printing quality evaluation parameters were put forward. The purpose was to provide reference data for quality evaluation in light-box cloth printing industry.

The purpose of this experiment was to demonstrate a quality analysis and control method for color management of EPSON 7600 color printer. The parameters of proofs, including solid density, dot gain, gray balance and color gamut were measured, and were compared with the offset quality. The paper put forward a practical solution for editing and optimizing color management and the profiles of devices. At the same time, the effect in Transmission and conversion of color information in standardized color management was analyzed and the evaluation model of color management and profile was established, which included subjective and objective evaluations.

Based on the experiment, this paper used principal component analysis and multiple regression analysis to establish a fuzzy evaluation system between the paper performance and print qualities. Five kinds of ink-jet paper with different surface characteristics were chosen in this paper to test their properties including absorbability, gloss, roughness, whiteness etc. During the same printing condition, using the digital proofer of EPSON Stylus Pro7880c, the standard wedge of GATF, solid color lumps and standard lines were printed on these paper samples; dot gain and solid densities were tested by SpectroEye, then contrast-K was calculated, the qualities of lines were analyzed with QEA image Analysis. Finally, paper surface characteristics were analyzed with principal components analysis, and definition of printing was analyzed by QEA Image Analysis, correlation between paper basic performance and the characteristics of printing qualities, such as dot gain, solid density, definition and contrast-K, and an integral evaluation function and a model were established. When evaluating on paper, as long as its surface characteristics were tested, the printability of different paper can be evaluated in a fuzzy and integral way through the calculation of the model and evaluation function. This work offers a certain theoretical reference and practical guidance to the selection of ink-jet paper and the improvement of ink-jet qualities.