Papers by Author: Zhen Cai Qu

Abstract: Sterile anti-shedding UV ink used on PE bottle cap was developed. The ink can be soaked in peracetic Acid solution with the concentration at 1800ppm for four hours’ sterilization under the constant temperature 90 °C, and there was no deinking phenomenon. The ink was prepared by mixed experimental method. The influence of prepolymer, monomer and photoinitiator on the UV ink properties such as curing speed, adhesion and solvent resistance were discussed. The optimum formulation of this sterile ink was as follow: PEA is 22.5%, PUA is 22.5%, TMPTA is 13.5%, DPGDA is 13.5%, 907 is 3%, ITX is 3%, carbon soot is 18%, defoamer is 4%. Under this condition, the properties of UV curing ink were as follow: curing time 10s, adhesion level 3 and good solvent resistance. The ink was an environmental ink used on plastic bottle cap.

Abstract: 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.

Abstract: Ink-jet printing is a non-contact printing, drops are jetted on the substrates to form images through the nozzles at a certain speed. Dot is the smallest unit in printing; the qualities of printing are seriously affected by dot gain. Ink spreading and penetration are discussed in this paper, influences on dot gain in ink-jet printing are studied, the original Young's equation and Washburn formula are theoretically amended, more scientific and rational models and formulas are obtained in the actual process of ink-jet printing, which offers reference standard and theoretical basis to improve the quality of ink-jet printing.

Abstract: The chemical composition of surface sizing agent BLD-02 was researched, as well as its synthesis method. BLD-02 was analyzed by infrared spectroscopy, and the main monomers were styrene, acrylate and acrylonitrile. In the process of synthesis, these monomers were prepared for copolymer latex by seed emulsion polymerization. Through a series of pre-trial, the results showed that when the contents of initiator and emulsifying agent were 0.3% and 3% (the percentage of total) respectively, the weight ratio of hard monomer to soft monomer was 2/3 and the reaction temperature was 75°C, the synthetic emulsion with higher viscosity, smaller particle size and well-dispersion was prepared. Results showed that the infrared spectrum and properties of the synthetic emulsion, to some extent, were as same as that of BLD-02.

Abstract: In this paper, allyl maleated rosin ester was synthesized by the esterification of maleic rosin and allyl alcohol with catalyst. And then a new waterborne paper-plastic composite adhesive was prepared through the semi-continuous emulsion polymerization method with allyl maleated rosin ester, butyl acrylate, vinyl acetate and acrylic acid as raw materials. The product of esterification was analyzed by IR spectra, and its acid value was determined too. Polymer was analyzed by DSC and IR spectra and its T-style peel strength was determined. The adsorption effect of adhesives to ink was also tested. The results showed that this paper-plastic composite adhesive had good adhesive properties: excellent compatibility with the ink, longer stability period, and low cost.

Abstract: Four kinds of ink-jet papers with different surface characteristics are chosen in this paper, by the ink-jet proofing experiments, the influence of surface characteristics to dot gain is studied, and the law of dot gain with paper surface characteristics is discussed. During the experiment, surface properties including absorbency, gloss, roughness and whiteness are tested firstly; then, the standard wedge of GATF is printed on these papers in the same printing conditions; finally, the dot gain is tested by SpectroEye. After experimental data processing and analysis, dot gain curves of different ink-jet papers are concluded, the law of dot gain with ink-jet paper surface characteristics is summarized. The results show that dot gain is different in different paper, the evaluation of 3# is the best; dot gain is also different with different colors in the same paper, and it is serious in cyan but light in yellow; the biggest dot gain appears in different contrast with different colors, cyan appears near the 65% dot area. The result of this paper offers a certain theoretical reference and practical guidance to the selection, the research and development of ink-jet paper as well as the improvement of ink-jet qualities.