Papers by Keyword: Waterless Offset

Abstract: In order to control the temperature of the ink, a cooling roller is used to cool down the temperature of the blanket cylinder. The calculation of the heat transfer on cooling roller is divided into two parts: One part is the exchange heat with the air through the cooling roller and the blanket cylinder, the other part is the heat conduction of the cooling roller and the blanket cylinder on the contact area. The heat conduction on the contact area is divided into the thermal conductivity generated by the friction and the heat conduction from blanket to the cooling roller.

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 observe the influence of monomer on the printing quality of UV waterless offset ink, ink samples with different monomer were made, and the main performance parameters such as viscosity, thixotropy, yield value, fluidity and stickiness were tested. Proofing by printability tester, and the printing qualities such as solid density, gloss, dot gain and print contrast were tested. Analyzing the influence of the difference of ink performance that caused by monomer on the printing quality of UV waterless ink. The results show that ink performances affect the printing quality directly. The differences of monomer’s structure and functionality have great effect on ink’s performance such as viscosity, thixotropy, yield value, fluidity and stickiness, and it can lead to the difference of printing quality such as solid density, gloss, dot gain, and print contrast.

Abstract: Design the formula of UV waterless offset ink, through changing the content of padding, different ink samples that with different rheological properties were made. Proof with the IGT printability tester, and the printing qualities of inks were tested. The influence of rheological properties on the printing quality of ink was analysis. The results show that the rheological properties influence the printing quality directly. The higher the viscosity of ink is, the bigger the thixotropy is, and the smaller the fluidity is. The solid density, gloss, ink-transfer rates and dot gain of the printed matter decrease with the increase of ink’s yield value.

Abstract: Waterless offset doesn't use dampening solution, so it has the advantage of color saturation that the water offset can not reach. Monomer is an important component of the UV waterless offset ink; it has great influence on the performances of ink. Ink samples were made separately by using different monomers. The flow curve, thixotropy crack index, surface tension, gloss, curing speed and other performance parameters of the ink samples were tested, and the influence of different kinds of monomer on the performance of ink was analysised. The results show that the viscosity of monomer affects the viscosity of ink sample directly; six monomers we used have good curing speed; the lowest surface tension can be got when using monomer with single functionality; and six ink samples have large thixotropy. The result of the compound EOEOEA, TPGDA and TMPTA is 0∶3∶7 by using the functionality design principle.