Papers by Author: Ling Ya Gu

Abstract: In order to improve the printing quality, 10 kinds of different manufacturers, different gram weight offset paper are used in this title, measure the quantitative, thickness, gloss, K&N values, and roughness of those paper. Print papers through IGTAIC2-5, calculate the ink transfer rate and transfer parameters. Using SPSS to analysis relationship between the performance of paper and ink transfer rate, transfer parameter b, k, f ' by using mathematical methods. The research results show that the performance of the paper affect ink transfer rate and transfer parameter b, k, f '; The tightness, roughness ,glossiness and K&N value have notable effect on the ink transfer rate and transfer parameter k; transfer parameter b, f ' has no remarkable influence.

Abstract: To solve the existent stability difficulties in the long term storage of the silver nanoparticle hydrocolloids (AgNPs) , this paper makes a comprehensive investigation on the effects of different synthetic methods which influence the stability of AgNPs. The controlled AgNPs are prepared by two kinds of precursors: silver diamminohydroxide ([Ag (NH₃)₂]OH ) and silver nitrate (AgNO₃ ) respectively precursors;in addition the stability of the AgNPs hydrocolloid is studied by UV-vis; A discovery was found after contrast :the particle sizes of the [Ag (NH₃)₂]OH precursor based AgNPs hydrocolloid are more uniformed,well controlled and of better dispersibility.this kind of AgNPs exhibits higher stability compared to the AgNO₃ precursor based AgNPs hydrocolloid.

Abstract: Curing rate is one of the most important performance parameters of UV curing system. During the curing process, curing degree is closely related to curing rate. Cross linking and curing degree of the system could be reflected by rheological characteristics. A method based on rheokinetics was used to characterize radical polymerization reaction which initiated by UV light. Changes of G’ (dynamic modulus) in every stage of curing process were real-time monitored by a rheometer equipped with UV curing accessory. The influence of varieties and contents of photo-initiators on curing process of polyester acrylates was studied. Associating conversion rate with dynamic modulus, a nonlinear kinetic equation was set up to describe the cure reaction. The results show that, this paper has put forward a method based on rheokinetics, to study the curing rate of UV curing system, and provided a new approach to study UV cure reaction.

Abstract: Four kinds of monomers were chosen to prepare ink to research the effect of monomer on the ink transfer performance of UV waterless offset and improve the printing quality. The rheological properties such as viscosity, yield value, thixotropy and stickiness were tested and the ink transfer equation was built, the ink transfer rate was calculated and the effect of monomer on the ink transfer performance was analyzed through the ink transfer experiment. The research results show that the type of monomers has large impact on the rheological properties of UV waterless offset, so the ink transfer performances with different kinds of monomers are different. And the viscosity, thixotropy, yield value and stickiness of the ink with TPGDA and EOEOEA are little, the ink transfer performance is better.

Abstract: In order to obtain good watermark on paper by printing, vegetable oil system and UV light-curing system watermark varnish were prepared by changing the type of vegetable oil, prepolymer and monomer, then test its permeability and refractive index, study the effects of these components on the performance of watermark varnish. Print watermark varnish by screen printing to examine the watermark. The results show that watermark varnish prepared with different type of vegetable oil has different permeability, but refractive index is very close. Adding prepolymer can improve permeability and refractive index of vegetable oil system watermark varnish. If the specific gravity of prepolymer and monomer is greater, permeability of UV curing system watermark varnish is higher. If refractive index of prepolymer and monomer is bigger, refractive index of varnish is bigger. Printing effect of UV curing system watermark varnish is better than vegetable oil system watermark varnish.