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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 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.

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.

A summary of basic screen printing procedures is given, covering the main factors in quality control. These include: various means of controlling thickness of deposit; the approach to printing extra fine line work; the mechanical characteristics of different types of squeegee and their practical effects; maximum print areas and print gaps in relation to screen sizes. The paper concludes with a detailed faultfinding chart with recommendations on the remedies to be adopted.

Different techniques applied for the fabrication of thick‐film fine lines have been analysed. The basics, achievements, advantages and disadvantages of improved screen printing, screen printing with metal masks, the direct writing method, offset printing and photoformed or photoetched thick‐film are presented. In addition, current trends in front metallisation of silicon solar cells are described. Based on a critical review, the use of thick‐film fine lines for this purpose is discussed.

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.

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.

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.

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.

The purpose of this study is to explain the effects of screen printing parameters on the quantity of ink deposited and the print quality in the context of printing of functional inks. Both these aspects of printing are crucial in the case of conventional and functional printing. This is because, in the case of conventional printing, the quantity of ink deposit affects the color strength while in the case of functional printing, it directly affects the resulting functionality of the ink layer.

In this work, an automatic lab-scale screen printer was used to print functional inks on a paper board substrate. The printing parameters, i.e. printing pressure and squeegee angle were altered and the resulting effects on the quantity of ink that was deposited were recorded. The quantity of ink deposit was related to its surface resistivity. In addition, the quality of the print was also assessed by examining the design registration quality.

The authors found that altering the squeegee angle has a significant effect on the properties of the resulting ink deposit. More importantly, the authors found that the deflection in the rubber blade squeegee was greatly dependent on the initial angle of the squeegee at the start of the printing stroke. For each set value of the squeegee angle that was considered, the actual angle during printing was recorded and used in the analysis. A printing pressure of three bars and squeegee angle of 20° resulted in the maximum weight of ink deposit with a correspondingly lowest surface resistivity.

This study is envisaged to have considerable practical implications in the rapidly growing field of functional printing of flexible substrates including, but not limited to, textiles. This is because, the study provides an insight into the effects of printing parameters on the characteristics of a functional ink deposit.

Screen printing of flexible substrates is a well-developed and arguably the most widely used printing technique, particularly for textiles. Numerous studies report on the analysis of various aspects of screen printing. However, to the best of the knowledge, the effects of printing parameters on the characteristics of functional inks, such as electrically conductive inks, have not been studied in this manner.