Papers by Keyword: UV Offset Ink

Abstract: In order to investigate the influence of filler on the rheological properties of UV curable offset ink, ink samples with various varieties and contents of fillers were prepared, the flow curve, thixotropy, dynamic and viscoelastic properties have been tested, and the rheological properties UV offset ink samples with various varieties and contents of fillers have been discussed. The results indicated that: variety and content have great influence on the rheological properties of ink samples. Sample use SiO₂ as filler has the highest viscosity, the largest thixotropy and G’; Sample use SiO₂as filler has the lowest viscosity, the largest thixotropy, while it’s G’ has no big difference from the sample use CaCO₃. Along with the increase of filler content, the viscosity, thixotropy and G’ will increase.

Abstract: There is more and more wide application of UV offset ink in green printing and packaging areas. The offset ink is emulsified inevitably and it will cause a great influence on the ink properties. UV offset ink samples prepared with different prepolymers. Base on the measurements of flow curve, thixotropy and dynamic viscoelastic properties under different emulsification ratio to explore the influence of emulsification on the rheological properties of UV offset ink as well as the effect on the rheological properties with different prepolymers at maximum emulsification ratio. The results indicated that the ink viscosity, thixotropy and dynamic viscoelastic properties decline as the increase of emulsification ratio. Compared with polyester prepolymer ink sample that the emulsified ink sample with epoxy prepolymer shows a faster declined in viscosity, lower thixotropy and larger G’ value. This variation trends relate to the viscosity and net structure of the emulsified ink system.

Abstract: The emulsification ratio of ink has an important effect on ink-transfer performance and printing quality. The UV offset ink of gold and silver cardboard was prepared by three-roll grinder. Ink was emulsified by adding different amounts of water and the ink samples with different emulsification ratio were made. Printability tester was used to proof, test the ink transfer performance, set up Ink transfer equation, confirm the parameters of f’，b and k, and investigate the influence of emulsification ratio on ink-transfer performance. Test the solid density, dot gain and relative contrast value of proofs, analyze the effect of emulsification ratio on printing quality. The research results show that when the ink of plate was large, the amount of ink transfer and the volume of ink on the plate are basic in a linear relationship. When the emulsification ratio of ink is 11.76%, the value b, the solid density and relative contrast value are the biggest. When the emulsification ratio of ink is 6.25%, the value f’ is the biggest. The dot gain is the smallest while the emulsification ratio is 15.67%.

Abstract: Prepolymer and monomer which are the main components of the UV ink have significant influence on the performance. By changing the proportion of prepolymer and monomer to make the different kinds of UV offset ink samples, the samples’ flow curve, yield stress, curing rate, glossiness, emulsification ratio, solid density and ink transfer rate were tested. And the effects of the proportion of prepolymer and monomer on the performance of UV offset ink were studied. The results show that with the decrease of prepolymer, the viscosity, yield stress and glossiness of the ink were reduce, and the curing rates were more or less the same. The emulsification ratio, solid density and ink transfer rate increased with the decrease of prepolymer.

Abstract: By means of simplex-centroid experimental design, three prepolymers EB3700，6358H and 6353-1 were used to define the proportion of composite prepolymers and the performances of the samples of UV offset ink with single prepolymer and composite prepolymers such as flow curve, thixotropy crack index, curing rate, glossiness, ink transfer rate and solid density were studied. The research shows that the ink sample with the prepolymer 6358H has higher viscosity and its thixotropy crack index is higher; the ink sample with the prepolymer 6353-1 has higher glossiness; the ink sample with the prepolymer EB3700 has faster curing rate, and its proof’s solid density is higher; the ink sample with the composite prepolymers EB3700 and 6353-1 has higher ink transfer rate. By means of simplex-centroid experimental design, the best proportion of three prepolymers EB3700, 6358H and 6353-1 is1.4:1:1.