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The paper aims to present results of investigations carried out on the front electrode of the solar cell. The front-side electrode for solar cells based on crystalline material is obtained by the screen printing method. Screen printing has been the prevailing method of electrode deposition because of its low cost. One of the ways to improve the cell efficiency and reduce the production costs is a further refinement of the metal electrode screen printing process.

The researches were focused on the modification of mechanical parameters of screen printing process to ensure the best possible cross-section of the front electrode geometry. The main printing process parameters were constant, however, the print speed was variable. The obtained fine line of front contact was characterized morphologically – the dimension and geometry of the front contact cross-section – by scanning electron microscopy technique.

The thin paths of 100 μm in width were screen printed applying a new silver-paste made by Du Pont. The printing speed has significant effect on print quality in the way that the lower speed enhanced the printed results.

For newest pastes (e.g. PV17D) influence of screen printing parameters on the front metallic electrodes geometry of solar cell is not so significant. Presented screen printing process can still give good results, but the further optimization for the new paste must be performed to achieve better cross-section geometry.

This paper confirms that one-step screen printing process can still give good results. The screen printed thin paths of 100 μm in width have good cross-section aspect ratio.

This paper aims to synthesize new screen-printing ink formula based on new derivatives of azo thiadiazol disperse dyes and evaluate their characteristics after being printed on polyester fabric substrates.

New dispersed dyes based on 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were prepared and confirmed by different analyses, infrared (IR), mass and nuclear magnetic resonance (NMR) spectroscopy, and then formulated as colored materials in the screen-printing ink formulations. Printing pastes containing the prepared dyestuffs and other ingredients were used for printing polyester using screen-printing or traditional printing. The characteristics of printed polyester fabric substrates were measured by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength, as well as light, washing, crock and alkali perspiration fastness, and finally, the depth of penetration was evaluated.

The prepared 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were obtained from the reaction of 5,5’-(1,4-phenylene)bis(1,3,4-Thiadiazole-2-amine) with resorcinol and m-toluidine as a coupling component. The suitability of the prepared dyestuffs for silk screen-printing on polyester fabrics has been investigated. The prints obtained from a formulation containing dye 1 possess high color strength as well as good overall fastness properties if compared to those obtained using dye 2.

The method of synthesis of the new dyestuffs and screen-printing ink provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes, and they are formulated in the screen-printing inks for printing on a polyester fabric substrate.

The prepared disperse dyes based on 1,3,4-Thiadiazole derivatives (dyes 1 and 2) could be used in textile printing of polyester on an industrial scale.

The basic parameters of screen printing are discussed, and an analytical model of the screen printing process is introduced. The ink roll in front of the squeegee is treated as a pump generating, close to the squeegee edge, high hydrostatic pressure which injects ink into the screen meshes. The shearing of the ink, the mechanics of screen snap‐off and the ink transfer taking place behind the squeegee are also analysed.

In 3D additive screen printing with constant snap-off, the inhomogeneous screen counterforce will influence the printing force and reduce the printing quality. The purpose of this paper is to study the relationship between scraper position, snap-off and screen counterforce and develop a variable snap-off curve for 3D additive screen printing to improve the printing quality.

An experiment was carried out; genetic algorithm (GA) optimization theoretical model, backpropagation neural network regression model and least square support vector machine regression model were established to study the relationship between scraper position, snap-off and screen counterforce. The absolute errors of counterforce of three models with the experiment results were less than 1.5 N, which was tolerated and the three models were considered valid. The comparison results showed that GA optimization theoretical model performed best.

The results suggest that GA optimization theoretical model performed best to represent the relationship, and it was used to develop a variable snap-off curve. With the variable snap-off curve in 3D additive screen printing, the inhomogeneous screen counterforce was weakened and the printing quality was improved.

In printing production, the variable snap-off curve in 3D additive screen printing helps improve the printing quality; this study is of prime importance to the 3D additive screen printing.

This paper is intended to be of interest to those involved in electronic applications of the screen printing process, including PCBs, membrane switches, thick film printing and instrument control panels. In recent years there have been a number of advances in screen printing technology which have significantly increased the capabilities and versatility of the process. Developments have included improvements in performance of screen printing machinery, mesh fabrics, stretching equipment, screen frame design, exposure devices, stencil systems and ink rheology and printability. In spite of these advances, there are many applications in PCB production where screen printing is under‐utilised, despite its cost effectiveness for volume board production when compared with dry film resists. This paper outlines some of the developments which have produced the modern screen stencils, and describes the rôle of mesh and stencil in determining the properties of the final printed result.

The purpose of this paper is to optimize the key parameters (mesh count, paper type and ink type) in screen printing, which are affecting the printed ink volume. The objective of the optimization was to maximize the color reliability by decreasing the color difference (ΔE value) of the prints while minimizing the ink consumption. Screen printing is still dominating the printing industry to make cost-effective production when high volumes are needed.

The experiment was designed using the Taguchi method, and the samples were prepared with screen-printing by using the standard squeegee angle and pressure. The effect of mesh count, ink type and paper type on ink consumption was evaluated with using analysis of variances and main effects plots of S/N ratio and standard deviation.

The factors ink type, paper type and mesh count were found significant for ink consumption due to their Probability (P) values which were lower than 0.05. It was determined that the mesh count was the most critical variable with the analysis of variance. The analysis showed that the selection of an optimum mesh count was the key to controlling the amount of the deposited ink. Although mesh counts were inversely proportional with the ink consumptions, they did not affect the color differences as expected.

The optimization of process parameters, that are most effective on the print quality, is necessary to minimize the ink usage and lower the costs and environmental impact without exceeding the desired ΔE value limits.

To develop a rapid manufacturing process for high‐volume free from fabrication of parts that is based on the high speed printing method which is screen printing. This technique will also be applied for printing in general.

This method involves continuous change in a layer's pattern (negative image of the layer) according to a very thin slice of the object to be printed. Three adaptive screen printing methods are proposed as an alternative to two dimensional screen printing. A comparative analysis is conducted and the possibility of combining the method is proposed.

Each of the three methods studied required further work as they all had major constraints. However, their combination may be the solution to the development of a rapid manufacturing process.

The originality is in the adaptive screen principle the screen being used will be capable to auto‐change the pattern of the layer to be printed instead of introducing a new stencil for every layer as in conventional screen printing.

The purpose of this paper is to analyse the screen printing liquid waste polluted soil physical, chemical and biological characteristics, with the unpolluted soil, and to analyse the application of some types of biochar towards the growth of mustard greens plants and the concentration of heavy metals Fe, Cr on the screen printing liquid waste polluted soil.

This research was conducted in a green house by using fully randomized design, split plot design pattern, with three replications. The main plot is the type of biochar, and the subplot is the dosage of biochar. The biochar consists of four types (B1 = chicken manure biochar, B2 = coconut shell biochar, B3 = rice hulls biochar and B4 = mahogany woods biochar). The dosage of biochar consists of four levels (D0 = control, D1 = 5 ton/hectare, D2 = 10 ton/hectare and D3 = 15 ton/hectare). The tested variable is being analysed by using analysis of variance (ANOVA).

The screen printing liquid waste polluted soil physical, chemical and biological characteristics analysis shows that the soil pH is neutral, a low C organic, a low N total, a high P, CEC and base saturation, while the texture is soft. The analysis results of rice hulls biochar physical, chemical and biological characteristics are quantitatively better in comparison with chicken manure biochar, coconut shell biochar and mahogany biochar. The quantitative application of rice hulls biochar15 ton/hectare dosage can increase the growth of mustard greens, and also, it recovers the soil characteristics by heavy metals total rate of 14.11 ppm Fe and 0.95 ppm Cr from the plant, while 209.05 ppm Fe and 4.12 ppm Cr were found in the soil.

This is one of few studies the biochar to screen printing liquid waste polluted lands. Currently, numerous kinds of chemical substances have been applied in a form of fertilizer and pesticide into the soil. Other activities like transporting the crop residues, and the contamination of irrigation water that is caused by screen printing liquid waste, have also affected the soil. It becomes degraded where the soil becomes compact and losses its nutrients, and it is containing heavy metals material that is toxic for plants. Biochar is applied into the polluted soil to improve the soil, which is hard to decompose and is long-lasting in the soil. These days, both the raw or ready food products are exposed to the heavy metals with a large and concerning number, especially in big cities which most of the soil is polluted.

Over the last few years, the increase in size of printed circuit boards, together with the increase in density of components, has made successful application of soldermask by conventional screen printing more and more difficult. This is despite improvements in both the screen printing resists and the equipment used. The accuracy produced by the photo‐imaging technique has been firmly established with the now almost universal use of dry‐film resist for the plating and etching of printed circuit boards. This led to the introduction of the dry‐film soldermask, but, unlike the dry‐film resists used for plating and etching, this type of soldermask has failed to gain universal acceptance, mainly because of technical shortcomings and high costs. The application of liquid soldermasks overcomes many of these technical problems, although the first attempts to achieve acceptable results required special equipment and huge capital investment. Photo‐imageable soldermasks which can be applied using the conventional printing and exposure equipment, available at printed circuit manufacturers, are now available. Some are processed in aqueous solutions, whilst others are processed in halogenated solvents of the types used in the processing of dry‐film resists. The introduction of such soldermasks makes available the combined advantage of liquid application and photo‐imaging, which will increase the overall quality of printed circuit boards produced, while utilising existing screen printed, oven, photo‐exposure unit and conveyorised spray developer.

Screen printing is a traditional low cost technique for production of electronic circuitry. Conventionally, screen printing is capable of no smaller than 200‐250 micron line and space (500 micron pitch) geometry in anything other than low volume production. In recent years, ERA has been developing a novel approach to screen printing which circumvents the problems with a traditional mesh screen and thereby allows dimensions down to 50 micron line and space to be printed consistently. A major European Commission sponsored project ‐ HIDENIMP ‐ has just commenced with the objective of transferring this manufacturing technology to European industry across a broad range of applications. These include microwave devices (where control of edge definition and gap is important), displays (where minimising track width enhances appearance), precision resistors (where the more controlled deposition characteristics of the μ‐Screen can be used and trimming minimised) and environmental sensors.