Papers by Author: Xian Fu Wei

Abstract: A nonvolatile memory based on an organic thin-film transistor (OTFT) with biopolymer of DNA-OTMA as the gate dielectric is fabricated. The device prepared by DNA-OTMA show a very large and metastable hysteresis in the transfer characteristics. In order to obtain the organic thin film transistor memory device with high electronic performance, one of the most widely used method such as post annealing have been applied to improve the quality of gate dielectric layer. In conclusion, the post-annealing at elevated temperatures plays a very important role in the performance of the OTFT memory device.

Abstract: This paper is to study factors that affect soaping color fastness of inkjet printing ink. Considering ink as a constant, discuss the affect of curing conditions on soaping fastness by altering curing temperature and curing time. Considering curing condition as a constant, study the affect of other factors on soaping fastness of ink, like particle size, the binder content and varieties of binder. The results show that: the soaping fastness is better when the curing temperature is 180°Cand curing time is 3minites; The smaller the particle size of ink is, the higher the soaping fastness is; the soaping fastness is well when the binder content of ink accounts for 20% of the total. The water-based polyacrylate and water-based polyurethane have the same effects on soaping fastness.

Abstract: In order to study influence of the variation of both viscosity and tack of the ink on the ink–transferring ratio. viscosity reducer and varnish to adjust ink viscosity and tack , the influence of the volume on tack volume and viscosity are obtained and also the influence of on the ink-transferring ratio by vatiation of the tack volume and viscosity . The results show that , the viscosity and tack of ink are both decrease with the amount of varnish and viscosity reducer increase. But varnish has a little effect on tack. Adding different proportion of varnish, ink-transferring ratio will reach best when the proportion of varnish is 2%. when addition more than 4%,the ink-transferring ratio will decrease instead. Adding different proportions of viscosity reducer, ink-transferring ratio will reach best when the proportion of viscosity reducer is 4%. When the amount of viscosity reducer more than 6%,the ink-transferring ratio will reduce instead.

Abstract: Inkjet Printing is a non-contact printing, and it has wide adaptability, high speed and intelligence, low cost and no pollution as well, so it is the best printing form for food and drug surface printing. Drops control technology is the key to the development of ink-jet printing technology, and viscosity is also the key factor that influences the drop state. In this article, the samples which have different viscosity are got by the way of adding different levels of resin to the ink. Drop state is observed through drops observatory, the speed, tail length and volume are measured by it in order to evaluate the influence of viscosity to ink-jet drop state. The result shows that viscosity has big influence to ink-jet drop state, if the viscosity is larger, the speed of drops is smaller. The ink with high viscosity is easier to gather into a circular drop than that with small viscosity. If the viscosity more than 13.2mPa•s, the rupture time and tail length of the drop increases along with the increase of viscosity. When the viscosity is 10.3mPa•s, its rupture time is 80s and the ink soon gather into a circular drop under the action of cohesion, its drop state is the best.

Abstract: Ink-jet printing technology is the mainstream of digital printing, and piezoelectric ink-jet printing is the main ink-jet printing at present, besides, drop’s injection and controlling technology is the key to the development of ink-jet printing technology. The surface tension plays an important role in the drop’s generation process, it will restrict the length and the state of the drop, further influence ink-jet printing quality. Six edible ink samples with different surface tension are prepared in order to research the influence of the surface tension to the piezoelectric inkjet Printing drop state, then the drop state is observed and its speed and volume are measured through drops observatory. The result shows that the speed of drop is higher if the ink’s surface tension is lower, but the drop is easier to gather into spherical drop and it also has smaller tail length and bigger volume.

Abstract: Ink printing density decides the quality of the printing. The content of resin type and additives, ink fineness and the content of primary inks were changed to improve the quality of the water-based gravure ink. Then use the proof machine of gravure to make a proof and test the printing density of the proofs. The influence factors of water-based gravure ink printing density were studied and the research shows that the ink printing density increases first, then decreases with increasing the content of the primary ink; the ink printing density increases with the ink fineness improvements; different kinds of resin has difference influence on the ink printing density; the ink printing density increases with increasing the content of resin; addition of an effective auxiliary can improve the ink printing density.

Abstract: To improve scratch-resistance and abrasion-resistance of water-based varnish, change the type of water-based resin, the type and content of wax emulsion and flow agent, then test scratch-resistance and abrasion-resistance of water-based varnish. The results show that resin and wax emulsion has a great influence on the scratch-resistance and abrasion-resistance of water-based varnish. Adding appropriate amount of wax emulsion can improve scratch-resistance and abrasion-resistance to some extent. Adding flow agent has certain influence on scratch-resistance of water-based varnish.

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: With the aim to study the effect of prepolymer on performance of UV ink-jet yellow ink , prepare UV ink-jet yellow ink color paste by change prepolymer and pigment/binder , test it’s particle size and distribution, explore the effect of different prepolymers and pigment/binder on the dispersion property; make ink color good dispersion paste into ink by using different film forming prepolymers, test the surface tension , viscosity , and curing speed, explore the effect of different prepolymers on the performance of UV ink-jet ink. The results indicate that, prepolymer on the dispersion property has great influence, color paste prepared by prepolymer CN2303 at pigment/binder for 2:1 has minimum particle size, and has good dispersion, film forming prepolymers has great influence on viscosity and curing speed of ink, has little effect on the surface tension of ink.

Abstract: People pay more and more attention to water-based printing inkjet ink which has no environmental pollution and fits environmental protection requirements. Inkjet printing technology could be applicable small batch and various variety products and satisfy the customer’s personalized requirements. Resin as one of the main compositions of printing inkjet ink has important effects on ink’s performance. To determine the effects of resin on the performance of water-based printing inkjet ink, adopting grinding method prepare the samples by changing resin and its proportion. By testing the samples’ particle size, viscosity, surface tension, pH value, the effects of resin on the water-based printing inkjet ink were analyzed. The results show that the type of resin and composite ratio has some effects on the performance of printing inkjet ink. When the resin was mixed in accordance with Resin B/Resin C=29/21, the performance of printing inkjet ink which was diluted with this resin was better.