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Wood-plastic composites for 3D printing from plant fiber (bleached pulp powder, mechanical pulp powder, newspaper pulp powder, eucalyptus powder, pine powder, and lignin) and polylactic acid (PLA), with silane coupling agent (KH550) as plasticizer, were prepared via melt extrusion. The physical properties, such as surface morphology, apparent density, tensile strength, melt flow rate, compatibility, and thermal stability were measured. Moreover, the effects of the content of various types of plant fiber powder in PLA on the properties of the prepared composites were investigated. The results showed that the modified lignin/PLA composite exhibited a superior performance under the same added amount. In particular, when the amount of lignin added was 15%, the tensile strength of the composite was 74.0% higher than that of pure PLA, and the melt flow rate was reduced by 17.8% compared with pure PLA. The density of the composite increased 15.8% compared with pure PLA when the lignin content was 20%. The scanning electron microscopy cross-sectional morphology and differential scanning calorimetry analyses showed that the optimal addition amount of lignin was 15%. Finally, the prepared lignin/PLA composite material was used in 3D printing with a smooth silky property and an excellent printing performance.

In order to study there production of UV ink-jet printing on different wood substrate. Using UV ink-jet printer, standard color patches are printed on wood substrate, wood substrate with white ink, and wood substrate with white ink and Varnish, and then the printed product color patches are measured using photometer, and then use MATLAB software program to form Color Gamut. According to the experimental data and the program running, the largest color patch in gamut is the wood substrate with white ink and Varnish. The gamut on the wood substrate of the white ink is less than the former, but significantly larger than the gamut on the untreated wood substrate. This will facilitate the flexible selection of different substrates for the printing of duplicates with different printing requirements on the wood substrate.

Because the traditional computer color matching algorithm can not give people an intuitive feeling, and the color matching process is difficult to understand, aiming at the above problems, an ink color prediction method and process were established. Firstly, the relative position of the ink color gamut in the CIEL*a*b* color space was determined by using the color gamut visualization technology. Then the position of the target color in the CIEL*a*b* color space and the ink color field was found, and the ink ratio of the target color was obtained by matrix calculation using the spectral data of the base color bar. The experimental results show that the method in this paper can meet the actual printing color requirements, and it can provide a new method for ink computer color matching.

In order to establish a more accurate Lithography database and reduce the color difference of computer color matching, the Lithographic suitability meter was used to establish a database under different conditions of substrate material, ink ratio and printing speed, so as to explore the influence of various factors on color difference in this experiment. The X-Rite Color Master was used to output color scheme to print sample strips that could produce color differences. The experimental results showed that the database created by the top part of the laser printing paper is relatively better and its color difference fluctuates around 3. The increase in the proportion of the ink not only makes the color difference smaller, but also reduces the fluctuation range of the color difference.

In this paper, in order to explore the effect of lignin on properties of hemicellulose/methyl-cellulose composite film, hemicellulose/lignin/methyl-cellulose composite films which were with different mass fraction of lignin successfully were prepared by using solution blending method. The morphology of the composite films was characterized. The composite films were tested for its absorbency, hydrophilicity, and tensile strength. The results showed that there was a strong interaction and good compatibility between the lignin, hemicellulose and methyl-cellulose in the composite films; the addition of lignin reduces the absorbance of the composite films and improves the water resistance of the composite films. With the increase of lignin, the tensile strength of the composite films first increases and then decreases. When the lignin content is 10%, the tensile strength of the composite film is as high as 40.95 Mpa, which is 77% higher than that without lignin.

With the rapid development of printing electronics, conductive ink as an important part of printing electronics, the electrical conductivity of which printed on different substrates has become the focus of research. In this paper, the printed circuit of different patterns and thickness of ink layer were printed on photo paper and PET film by using the nano-silver conductive ink with the particle size of 30 nm and solid content of 5–10%, and its conductivity was tested under different sintering temperature. The experimental results showed that the circuit could still maintain good electrical conductivity with the change of printing pattern. As the thickness of the ink layer increases, the circuit width becomes wider, the conductivity of the circuit gradually increased and it decreased after reaching a certain number of layers. The conductivity increased rapidly with the increase of sintering temperature and it tended to be stable after slowing down when reaching a certain temperature. As the sintering time going by, the electrical conductivity of the circuit increased swiftly first and the growth trend became slower.

The color gamut boundary description algorithm is used to describe the size of the color gamut boundary and ensure the accurate prerequisite for the conversion of the color gamut mapping. With the development of the research, the application scope and content of the color gamut boundary description are becoming more and more extensive. Firstly, the paper summarizes the development of the color gamut boundary extraction algorithm, characterizes the realization principle of the color gamut boundary description algorithm and predicts the color transfer range which can be achieved by a given color reproduction medium. And then the method of color boundary description algorithm and color gamut mapping algorithm was studied. Finally the paper put forward the views and assumptions in allusion to the problems in the practical application.

Paper is widely used as a substrate for inkjet printing, where the paper feature heavily impacts the print quality, especially the color reproduction. The unprinted area on paper is visible and applied as a background reflectance for the toner layer. Hence, it is worthwhile to understand the effects of paper whiteness on print color reproduction. In this study, the tested papers were treated with different dyes, which resulted in the change of the paper’s optical properties, but not surface roughness. The print density was impacted by the paper whiteness and ISO brightness. The effect of the paper whiteness on the print density is a stronger linear correlation compared to the ISO brightness. Paper whiteness has a positive correlation with the ISO brightness. The print colorimetric values (lightness and chroma values) increased with increasing paper whiteness up to a certain level, after which the paper whiteness did not have a noticeable impact on its print lightness and chroma values. The print color (a* and b* values) was affected by its corresponding paper color.

The environmental pollution problems cause for people’s concern in recent years. Due to using environmental aqueous spot-color ink, flexographic printing shows a great potential, and the problem of high-precision flexographic printing color matching also becomes a hot topic. In this paper, the problem of computer color matching of flexographic printing aqueous spot-color ink was studied. Using flexographic IGT printability tester and yellow, magenta, cyan primary colors of ink to carry out color matching experiments and obtain the color samples by changing the concentration ratio of base ink. After utilizing the spectrophotometer to measure the chromatic, we take Kubelka-Munk theory as the guide theory, which studied the color model based on the theory of the new double constant Kubelka-Munk and the model of spectral matching based on weighting factor, and carried on the evaluation. The experimental results show that the spectral color model based on the weighting factor has higher precision of color matching in terms of color model of the new double constant Kubelka-Munk theory.

Paper properties, especially paper optical properties, are important factors for ink-jet print color reproduction. The objective of this work was to explore the influences of paper optical properties on print color reproduction. Herein, papers were sized with different dyes which affect paper optical properties but had little effect on the other properties. CIE whiteness is better than ISO brightness to express the paper color, because CIE whiteness not only shows the paper lightness but also exhibits the color of paper. CIE whiteness of paper is an effective way to express the color reproduction. The color reproduction is mainly influenced by a* and b* values of paper. L* value above 94 did not have a significant impact in lightness of printed sample. The effect of paper CIE whiteness on color reproduction could be decreased by improving ink cover properties.

The goal of this paper is to improve the robustness of the tracking by detection system. We gain the aim by dynamic tuning the learning parameters for an accumulative learned classifier according to online performance evaluation. Firstly, two kinds of tracking loss measures are distinguished: one is positive due to object appearance variation which does not result in drift; the other is negative which really causes drift. Then, according to these two situations, different parameter updating strategies are proposed to maintain adaptive model updating. Our proposed algorithm adopts the ability of identifying track loss and controls the tracking process to enhance the stability and robustness of the original algorithm (CT), and experimental results show better performance with negligibly small additional running time on some challenging video fragments which original CT failed on.

Some experiments were designed to check the effects of monitor parameters such as color temperature, brightness, and gamma value on soft proofing. We have two illuminant levels D50 and D65, two brightness levels 100 and 120, and two gamma value levels 1.8 and 2.2 to be chosen in constructing international color consortium profiles (ICC profiles). Then, soft proofing simulation experiment was executed. Comparisons were made between the results of soft proofing and printer to obtain the optimum parameters. Results were evaluated by color difference analysis, individual component analysis of \( \Delta L^{*} \),\( \Delta a^{*} \), and \( \Delta b^{*} \) values, and psychophysical experiments. Experiments show that the performance of soft proofing varies a lot with different parameters. And it can get a better performance with the appropriate parameters. At last, the optimal parameter combination was obtained.

As printing technology is developing to informatization, networking, and automation, traditional proofing methods are no longer meet the needs of the development of printing. Based on the research of the development of proofing technology at home and abroad and comprehensive analysis of the existing remote soft proofing system, we find that the high requirement to the client’s display equipment in existing remote soft proofing system leads to customers’ excessive costs when bringing in the remote soft proofing system. By means of color management to the display device, the paper studies the effect of different displays in the process of remote soft proofing and gets a good proofing result among the acceptable color tolerance when using normal display devices as the client and the color is also in the acceptable range for remote soft proofing. Experimental results show that in the use of professional display for remote soft proofing, the average color difference is less than 3 and proofs can achieve good results. When using conventional LCD display remote soft proofing, the average chromatic aberration is 5.71, and the maximum color difference is not more than 7. In the case of less demanding color printing, you can choose conventional LCD display.

Because the model of flexographic spot-color matching based on Kubelka–Munk theory is proposed for the dye matching, it will produce color difference and affect color accuracy when it is applied to the ink matching. In this paper, the model of computer color matching based on double-constant Kubelka–Munk theory is improved. The model of flexographic spot-color matching in which the water-based ink is used as printing ink and corrugated paper is used as substrate is formed. In this model, first the sample data are obtained by using IGT printability tester. Then, tristimulus value matching theory is its basic, and a series of mathematical calculations are used to obtain the initial matching values. And then, a more accurate formula is obtained through multiple iterations. Finally, the improved matching model is completed. The experimental results show that the model can quickly complete the color matching, and the result is accurate and stable. Moreover, the matching model meets the requirements of environmental protection and has good prospects.

This paper presents some results from an experiment of image softproofing under different International Color Consortium (ICC) rendering intents, which will be available for selecting an appropriate rendering intent in printing processes. In a screen softproofing procedure, image is converted via ICC profile embedded in image itself to output device profile, then to proofing device profile. With the rendering intent of absolute colorimetry in the second conversion, the effects of different rendering intents in the first conversion have been investigated through a softproofing software developed in Matlab 7.0. A variety of testing images, including light tone, shadow detail, etc., are used for image softproofing. The color differences between original images and proofed images are calculated under the S-CIE L*a*b* color difference formulae. Comparisons and analyses on the obtained images under four rendering intents show the effects of color characteristics of original images on rendering intent selection.

The aim of the investigation was to determine the influence of rendering intents on the gamut volume and the visual evaluations in digital proofing. According to that, the corresponding test form was used for the needs of investigation and printed on Epson style pro 7800 with the application of ICC standard rendering intents (perceptual, saturation, relative colorimetric and absolute colorimetric). Based on the results obtained by spectrophotometer measurements, the gamut of the digital proofing was illustrated with the ColorThink software in CIE L*a*b* color space. The analysis in relation to the results of visual evaluations shows the difference influence of the rending intents to digital image quality.