Study of Fluid-Structure-Contact Interactions for Ink Transfer Modelling in a Contact-Based Printing System

The ink transfer rate and ink absorption rate directly affects the quality of printing matter, so it is very important to know the influence factors of the ink transfer rate and ink absorption rate. This paper studied on the impact of offset paper smoothness and offset paper absorbency on the ink transfer rate, the impact of offset paper compactness and offset paper absorbency on the ink absorption rate. The results show that ink transfer rate is affected by offset paper smoothness within a certain range. The ink transfer rate is affected greatly by offset paper absorbency. The ink absorption rate is greatly affected by offset paper compactness and absorbency.

The ink transfer rate has an important influence on the printing quality. The primary aim of the printing process is always to achieve a high ink transfer rate. This paper used a printability tester to test three different types of paper: coated paper, offset paper, and newsprint, and adopted an approximate method to calculate the ink transfer equation to test the absorbency, surface smoothness, and elasticity of the papers. Furthermore, we developed a linear regression model based on the measured values. Analyzed and explored the influence of paper properties on the parameters of the ink transfer equation. The experimental results show that the maximum ink transfer rate of a newsprint paper is higher than that of an offset paper and coated paper under the same ink and printing conditions, with the optimal ink supply to the coated paper being the smallest. The ink absorption and smoothness of a paper were found to significantly influence the ink transfer parameters.KeywordsInk transfer equationInk transfer ratePaper performance test

According to ink transfer law, the text analyses the developing trend on influencing factors of ink transfer rate including printing speed, printing pressure and printing material. Through large amounts of experiments, three types of influencing datas have been obtained. Based on polynomial regression method, experimental datas have been fit with Matlab software and the fitting curves of the three influencing laws on ink transfer rate can be gotten. By analyzing the tendency of the influence of three factors quantitatively, the results show surface smoothness of printing material has the least influence on ink transfer rate in three factors including printing speed, printing pressure and printing material, and the printing speed and printing pressure have similar influence on ink transfer rate roughly. The experimental research has active significance to take corresponding measures to control processing parameter, keep printing process and ensure stabitity of printing mass.

In order to understand the effect of ink viscosity and printing speed on the ink transfer rate of gravure offset printing, a plate-to-plate offset printing equipment was assembled to simulate the gravure offset printing system. The images of the ink transfer process between two plates was deliberately recorded for further calculation. The experimental results revealed that the ink transfer rate increases as the plate velocity increases, especially this effect is more pronounced for higher viscosity ink. Our experimental results demonstrate that the mechanism of ink transfer rate is strongly subject to the mutual reinforcement between plate velocity and ink viscosity that could suppress the effect of surface hydrophobicity difference between the top/bottom substrates on ink transfer rate ultimately.

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.

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.

The pattern shape engraved on the gravure printing roll is one of the most important factors influencing ink transfer. This study is focused on the relations between dot geometry engraved on gravure printing roll and the ink transfer during the gravure printing process. The influence of dot width on printed patterns will be demonstrated. Results reveal that as the width of a dot on the printing roll increases, the ink transfer rate also increases. But over a certain size of width, surface uniformity began to recede. Therefore, proper dot geometry on the printing roll should be decided to guarantee good printing quality according to printing conditions and expected performance of the electronic devices.

The transfer rate of gravure water-based ink is one of the key factors to ensure the quality of printing production. The influencing factors of ink transfer in gravure printing are analyzed. The printing pressure changes the gap between the ink and the substrate so as to adjust the capillary action strength. Thereby the ink transfer rate is changed. Printing speed affects the ink transfer rate by changing the transfer time of the ink in the contact area. When the viscosity of the ink changes, the amount of ink obtained in the net hole will change, and the transfer rate will also change. The ink transfer process was simulated by FLUENT software. The ink transfer volume under four printing pressure, at six different printing speed and with seven different viscosity was analyzed respectively and the optimum parameters were given. The results show that the transfer rate increases with the increase of pressure and the transfer rate decreases with the increase of rotating speed and the viscosity of the ink.

In this paper, using rotational viscometer measured the viscosity of ink，using IGT printability tester complete the transfer of the ink on different paper, using the analytical balance measure the amount of ink transfer, and using transfer rate formula calculate the ink transfer rate. Using EXCEL to establish the ink viscosity and the transfer rate curve, And fitted curve equation, thus that obtained conclusion of different ink viscosity affect ink transfer on different paper.

Ink transfer rate (ITR) is a reference index to measure the quality of 3D additive printing. In this study, an ink transfer rate prediction model is proposed by applying the least squares support vector machine (LSSVM). In addition, enhanced garden balsam optimization (EGBO) is used for selection and optimization of hyperparameters that are embedded in the LSSVM model. 102 sets of experimental sample data have been collected from the production line to train and test the hybrid prediction model. Experimental results show that the coefficient of determination (R2) for the introduced model is equal to 0.8476, the root-mean-square error (RMSE) is 6.6 × 10 (−3), and the mean absolute percentage error (MAPE) is 1.6502 × 10 (−3) for the ink transfer rate of 3D additive printing.

The difference of printing quality depends on the transfer of ink and paper performance.In this paper based on the theory of printing.Measuring the performance of all sorts of paper,with IGT-C1 type printability tester to simulate the printing principle.In the same printing pressure,printing speed and ink,under the conditions of constant temperature and humidity.Using different paper type experiment,obtained paper all kinds of performance and ink transfer data.Then processing, analysis,and obtained paper performance and ink transfer rate relation curves of in printing pressure and the printing speed with constant.For the printing quality control to provide certain basis in the different performance of paper.

On-demand heart valve manufacturing using focused rotary jet spinning

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.

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.

When the manufacturer of a medical device alone bears the responsibility for alerting recipients that the device may be defective, there is a certain temptation to gloss over the risk. The story of the Bjork-Shiley Convexo-Concave heart valve is a case in point. If the steering mechanism on your car is found to have a manufacturing or design defect, the National Highway Transportation Safety Administration directs the manufactuer to send a letter to all owners of the model (a registry is kept for this purpose) with instructions concerning replacement or repair. Owners are thus warned about the problem and given information about what to do about it, and manufacturers are prepared to make the necessary adjustments. This arrangement assumes that owners have a right to know about relevant defects, manufacturers have an obligation to inform and repair, and the government has the responsibility to oversee this process. While this arrangement is not perfect, it acknowledges the vulnerability of consumers and the corresponding obligations of the manufacturer and the government to protect them. What happens if a similar situation arises with your implanted artificial heart valve? Is there a similar system to warn recipients and provide information about what to do? The recent failure of hundreds of Bjork-Shiley Convexo-Concave (C/C) mechanical heart valves provides a case study on how information about the risk of failure was communicated to patients and the medical community. Unlike automobile recalls, the arrangements for dealing with defective heart valves were--until recently--indirect, ineffective, and marked by serious conflicts of interest. None of the three groups responsible for protecting patients with artificial heart valves--the Food and Drug Administration, the physicians and surgeons whose patients received the device, or the manufacturer (Shiley, Inc., of Irvine, California)--adequately responded to the discovery that the C/C valves were susceptible to strut fracture. The system placed commercial and professional interests over the rights of patients. Mechanical Heart Valves The development of mechanical heart valves is one of the success stories of contemporary medicine. Many persons with diseased heart valves become seriously disabled and soon die unless a prosthetic valve can be installed. The first mechanical heart valves were implanted in 1960, and since then their use has grown rapidly. Today about 40,000 American receive artificial heart valves each year.[1] Shiley, Inc., has been a pioneer in the development of mechanical heart valves. In 1974 they developed their radial spherical (R/S) valve, consisting of a disk attached to two wire struts that allow it to swing open and shut in response to blood flow. The struts are welded to a metal ring that is covered with a teflon sewing ring for attachment to the heart. In 1979 Shiley introduced a similar valve, the 60[degrees] Convexo-Concave (C/C), which they believed would improve blood flow through the valve. A C/C valve that opened to 70[degrees] was also manufactured, but it was not approved for sale in the United States. Blood clots (thromboses) caused by the presence of artificial implants are a serious problem and are responsible for the greatest percentage of complications that occur. Because the movement of blood is obstructed by the valve, there are areas of relatively stagnant flow where clots can form. They may form on the valve, preventing it from fully opening or closing, or they may break free and cause strokes, heart attacks, and other serious complications. Drugs to thin the patient's blood and reduce clotting are an essential part of the treatment after implantation, but there is a limit to their ability to reduce the incidence of thromboembolism--blood clots that break free and lodge in an artery, cutting off blood flow to tissues or organs. Shiley's 60[degrees] C/C valve, which appeared to allow better blood flow and promised a lower incidence of thromboembolism, was regarded as a significant improvement in heart valve technology. …