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An important thiol ester photosensitive monomer COMP (CO-based mercaptopropionate) was prepared via melt polycondensation method using castor oil (CO) and 3-Mercaptopropionic acid (3-MPA). Structure of the thiol-compounds was characterized by FT-IR, 1H-NMR. When the thiol compound was used as photosensitive monomer and polyurethane-acrylate prepolymer was used as main material in UV curable adhesive. The UV curable adhesive showed good curing behaviors and thermal stability with curing time 100s, T-peel strength 3.8N/25mm and shrinkage rate 8%; so the UV curable adhesive could meet the requirements for flexible packaging composite.

Three thiol-compounds with different functionalities were synthesized through esterification reaction which was prepared by 1, 4-butanediol, trimethylolpropane, and pentaerythritol and 3-mercapto propionic acid respectively. Thiol-compounds and polyurethane-acrylate prepolymer were blended with addition of photo-initiator in certain proportions in order to form polyurethane curing film under UV irradiation. The structure and properties of the thiol-compounds and the polyurethane curing film were characterized by NMR, FT-IR, and TG. The results showed that the thiol-ene addition reaction between the urethane acrylates and the thiol-compounds was preceeded. With the increase of functionality of mercaptopropionic acid ester, the thermal stability improved, and the T-peel strength enhanced. When the moral ratio of urethane acrylates and trimethylolpropane-3-mercapto propionic acid ester was 1:1, the adhesive showed the best mechanical properties and thermal stability with curing time 40s, T-peel strength 88N/m and 50 % mass loss at 369°C, respectively.

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.

We proposed overall design of the visualization browsing map data in network environment in this paper. And we developed map data flow according to the data structure and attributes of map data base. We programmed one map display control, MapCtrl.ocx, with GUI in the specific implementation. It could browse the map by utilizing map data base and self-designed map symbol base. Furthermore, we detailed the specific process of programming the control and the related techniques, such as component technique, data exchange technique and display technique. We developed a prototype of map data visualization browsing system based on ActiveX in network environment, which could achieve several functions such as browsing vector graphics of map data on internet, operation and simple query and analysis.

Image halftoning is the core technique of digital image output, which determines the quality of the color and tonal gradation reproduction. In this paper, the existing halftoning techniques were analyzed and evaluated, such as FM halftoning and AM halftoning, etc. And a new halftoning mode, frequency conversion amplitude modulation (FCAM), was proposed. This method is still based on AM halftoning, but it uses the different screen frequency for halftoning image of the different color version, so as to avoid moiré fringes on the smaller superposition angle. The use of new halftoning model can achieve halftoning image output which is more than 4 colors (such as 6 colors or 7 colors) without visual moirè pattern when overprinting. By the new technique, high-fidelity printing is achieved, and the color gamut of the output image is expanded, and we can get more vivid realistic effect of image transmission. We tested color gamut expansion of 6 colors and 7 colors high-fidelity printing, and obtained the expected conclusion by quantitative analysis.

The impact of coated paper printability for image quality on the high-fidelity digital printing was studied in this paper. Compared with the traditional printing technology, high-fidelity digital printing technology is more likely to expand the color gamut, maintain the original tone linear and produce vivid image. The performance of coated paper to a large extent determines the image quality. In order to get high-quality printed matters, the mechanism of the coated paper printability influencing on the performance on high-fidelity digital printing is need to be researched in-depth. The printability of coated paper was studied from several aspects in this paper, including the structural properties, roughness, optical properties, absorption etc, the relationships between these properties and printing color, dot reproduction performance were also studied. Based on the previous theoretical and practical studies, the printability evaluation system of coated paper on high-fidelity digital printing was established initially. On digital printing, accurate color management technology also affects the printing quality as the performance of coated paper, so the advanced color management technology was also used in the current study. The results showed that the pore structure and the absorbent of coated paper were the most important factors for affecting the printing quality, and the roughness and optical properties of coated paper also had a certain impact.

In this study the effect on quality measurement introduced by input precision of instrument in image digitizing process was verified through a series experiment. Two categories of samples, which were outputted by EPSON Stylus Pro7880c digital inkjet printer and Xerox DocuColor5000 digital xerographic printer individually, were transformed into digital image with a normal flatbed scanner in 600 DPI, 1200 DPI and 1600DPI resolution. The area quality attributes such as graininess, mottle, NPS and banding were surveyed and analyzed with the aid of PIAS™-II personal image analysis software to investigate the stability of normal instrument used in digital prints measurement system. Results show that precision demands are different for various quality parameters and different application backgrounds, namely it is precise enough for common industry detection which has lager tolerance, but higher resolution does good to more effective and more precise measurement especially in R&D.

A low-viscosity and solvent-free polyurethane adhesive was prepared with mixed polyester, polyether and IPDI as main raw materials. The influences of different moral ratios of polyester and polyether on reaction time, viscosity and water resistance, adhesive strength were researched. The effects of catalysts to adhesive were well discussed. The experimental results showed that polyurethane adhesives composed by mixed polyester and polyether had low viscosity and had better waterproof quality. The adhesives showed the best comprehensive properties when the mole ratio of OHs of polyether to OHs of polyester was 0.3/0.7. Catalysts added to this adhesive could speed the curing reaction, but it reduced the peel strength of the adhesives.

The penetration and diffusion of ink droplet in paper coating have significant influence on the image quality in the inkjet imaging. The flight physical phenomenon of the ink droplet was researched and analyzed according to the hydrodynamic equations of multiphase flow discrete phase in this paper. Base on studying on the surface structure of paper coating, the mechanism of impact, penetration and diffusion between ink droplet and paper coating also was researched in this paper from the perspective of energy conversion in the imaging process. The proposed mathematical model consisted of the factors of hydrodynamic characteristics for ink droplet and the physical characteristics of paper coating, we could get the maximum diameter of ink droplet spreading in paper coating through solving the model and obtain viscous loss and energy consumption in penetration of ink droplet by experiment, and then calculated the average penetration depth of ink droplet.

This paper draws on a roll coating method which used for the production of coated paper. Polylactide coating cardboard was prepared through the solvent coating, and study its packaging performance. In this study, chloroform is based solvent, ethanol or n-propanol as auxiliary solvents, poly (ethylene glycol) or poly caprolactone as plasticizer, and the water vapor permeability, oxygen permeability and heat sealability of polylactic acid coated cardboard.

In this paper, the key research was focused on the algorithm based on wavelet domain after analyzing and comparing several watermark algorithms. Disperse Wave Transform(DWT) watermark and Disperse Cosine Transform(DCT) watermark are both belong to transform domain technology, and they have more robustness than spatial-temporal domain technology, and DWT is superior to DCT. DWT can use the spatial-frequency characteristics of Human Visual System, and Mosaic will not appear in reconstruct image. DWT also can use image fusion technology to disperse watermark into multiple scales of carrier data, and got more robustness. In this paper, watermark embedding based on wavelet domain in which raster data are carrier was performed, then extracting and detecting watermark were done. Experiment results show that digital watermark based on wavelet domain will get better invisibility and robustness, and can be used in following the data by digital fingerprint.

This paper studied on the application mechanics and characteristics of the polyurethane-acrylate composite emulsion applying to the pre-coated adhesive film of paper and plastic laminating. The formula design and synthesis method of the polyurethane-acrylate composite emulsion was researched, and the physical properties of the copolymer emulsion was tested by infrared spectroscopy (IR), particle size analysis, gel permeation chromatography (GPC). According to mix the waterborne polyurethane acrylate emulsion to the waterborne rosin emulsion, the hot melt pre-coated adhesive was obtained. The experimental results based on the physical properties and image analysis of the pre-coated adhesive film of paper and plastic laminating showed that: the adhesive film coated by this hot melt adhesive had a high gloss and adhesive force, it improved the application performance of the pre-coated adhesive film of paper and plastic laminating in the printing and packaging industry.

UV ink has many advantages such as less pollution, high curing speed, saving energy, so it has been widely applied in traditional printing and emerging digital printing. In this paper, the two curing principles in UV ink which are free-radical curing and cationic curing, are discussed and compared, and the factors that affect the curing rate are analyzed through the comparing experiment of the curing rate. In the last, the selection principle of photoinitiator is established by means of analyzing and comparing curing rate when various photoinitiator or photoinitiator combinations is used in UV-cured ink. These studies have certain significance for improving the curing efficiency of UV ink and its application.

Polyurethane-acrylic composite emulsion was synthesized by swelling polymerization with aqueous polyurethane dispersion as seed, and acrylic as monomers. The obtained polyurethane-acrylic (PUA) composite emulsion were characterized by means of IR spectra, and the results showed that the obtained emulsion was hybrid emulsion of polyurethane and acrylic, which had smaller particle size and higher viscosity and was more suitable for the preparation of ink. The obtained water-based PUA emulsion and alkyd resins were used as ink binder. The obtained water-based ink had good water resistance, color density, gloss and friction fastness.

Nano-silver has received a great deal of attention in recent years for its various potential applications on medical, electronic, optical, etc. In this paper, we developed a simple way to synthesize nano-sized silver by liquid chemical reduction method with hydrazine hydrate as reductant and PVP as surface-protection reagent. In the experimental design, orthogonal test with three factors and three levels is adopted, which investigated the effect of instillation method, the PVP amount and the reaction temperature on the size and morphology of silver nano-particle. Through analyzing the orthogonal experimental results, the optimum conditions for nano-silver preparation is obtained, in which hydrazine hydrate solution is instilled into the mixture solution of silver nitrate and PVP, the molar ratio of PVP/AgNO3 is 1.5, and the temperature is 50°C. Scanning electron microscopy was used to characterize the morphology of silver nano-particles, and the results show that the dispersed spherical nano-particles with the average size of about 60 nm can be prepared in this work.

Solvent-free adhesive is a kind of environmental friendly adhesive which is safe, less material consumptive and just needs simple curing conditions. In this paper, the two components solvent-free polyurethane adhesive for flexible packaging was discussed, including its characteristics, composition, curing and adhesion mechanism and three modification methods. The curing mechanism of this adhesive is that crosslinking happens between –NCO and –OH which are contained in two components respectively. However, its adhesion mechanism is different when the adhesive is bonding with polyester film, paper, fabric, metal and other materials. The modification methods of two components solvent-free polyurethane adhesive include modification of its soft segment, modification with epoxy resin and modification with organosilicon and so on. The performance of adhesive can be improved through modification.

Printing electronics technology promotes the application of conductive ink. In this paper, the manufacture of nano-sliver conductive ink is investigated. First, Spherical silver nano-particles were reduced from silver nitrate solution by liquid chemical reduction method, with hydrazine hydrate as reductant and PVP as surface-protection reagent. SEM was used to characterize the morphology of silver powders, and the mean particles size is 62.79 nm. Then, conductive ink was prepared with nano-silver particles made in this research as conductive fillers, polyurethane resin and acrylic resin as binders, and stearic acid as dispersant. In the last, the conductive ink was printed on the PCB substrate by screening printing. After the ink is dried, conductivity, abrasion resistance, and adhesion were tested. The experiment results shows that the order of sheet resistivity magnitude is 10-4Ω•m, the number of rubbing fastness is more than 6000, and the adhesion can be resisted repeatedly to tape tear.

The infiltration and diffusion of ink droplet in paper coating have significant influence on the image quality in the inkjet imaging. The flight physical phenomenon of the ink droplet was researched and analyzed according to the hydrodynamic equations of multiphase flow discrete phase in this paper, and the energy distribution of ink droplet before contacting with the paper coating was calculated. Base on studying on the surface structure of paper coating, the mechanism of impact, infiltration and diffusion between ink droplet and paper coating also was researched in this paper from the perspective of energy conversion in the imaging process. The proposed mathematical model consisted of the factors of hydrodynamic characteristics for ink droplet and the physical characteristics of paper coating, we could get the maximum diameter of ink droplet spreading in paper coating through solving the model and obtain viscous loss and energy consumption in infiltration of ink droplet by experiment, and then calculated the average infiltration depth of ink droplet.

This paper studied on the hydrokinetics and uniform distributed mechanics of supplying ink pressure for the inkjet printing system based on the, and the advanced testing equipment. According to the analysis of theoretical calculation and CFD, we designed a new type of equipment for supplying ink, including the structure of the transition pipe. This supplying ink equipment could make the ink droplets distribute under the equal pressure on the cross direction. The experiments showed that this new supplying ink equipment could make the ink droplets distribute under the equal pressure and uniform velocity on the cross direction, so it greatly improved the imaging effects for the inkjet printing system.