Gravure Plate Research Articles

Forced dynamic dewetting of structured surfaces: Influence of surfactants

We analyse the dewetting of printing plates for gravure printing with well-defined gravure cells. The printing plates were mounted on a rotating horizontal cylinder that is half immersed in an aqueous solution of the anionic surfactant sodium 1-decanesulfonate. The gravure plates and the presence of surfactants serve as one example of a real-world dewetting situation. When rotating the cylinder, a liquid meniscus was partially drawn out of the liquid forming a dynamic contact angle at the contact line. The dynamic contact angle is decreased on a structured surface as compared to a smooth one. This is due to contact line pinning at the borders of the gravure cells. Additionally, surfactants tend to decrease the dynamic receding contact angle. We consider the interplay between these two effects. We compare the height differences of the meniscus on the structured and unstructured area as function of dewetting speeds. The height difference increases with increasing dewetting speed. With increasing size of the gravure cells this height difference and the induced changes in the dynamic contact angle increased. By adding surfactant, the height difference and the changes in the contact angle for the same surface decreased. We further note that although the liquid dewets the printing plates some liquid is always left in the gravure cell. At high enough surfactant concentrations or high enough dewetting speed, the dynamic contact angles in the structured surface approach those in flat surfaces. We conclude that surfactant reduces the influence of surface structure on dynamic dewetting.

Assessing Ink Transfer Performance of Gravure-Offset Fine-Line Circuitry Printing

In this study, the printing mechanism and performance of gravure-offset fine-line circuitry printing technology are investigated in terms of key printing parameters through experimental and theoretical analyses. First, the contact angles of the ink deposited on different substrates, blankets, and gravure metal plates are experimentally determined; moreover, their temperature and solvent content dependences are analyzed. Next, the ink solvent absorption and evaporation behaviors of the blankets at different temperatures, times, and numbers of printing repetitions are characterized by conducting experiments. In addition, while printing repeatedly, the surface characteristics of the blankets, such as the contact angle, vary with the amount of absorbed ink solvent, further affecting the ink transfer performance (ratio) and printing quality. Accordingly, the surface effect of the blanket due to ink solvent absorption on the ink contact angle is analyzed. Furthermore, the amount of ink transferred from the gravure plate to the blanket in the “off process” and from the blanket to the substrate in the “set process” is evaluated by conducting a simplified plate-to-plate experiment. The influences of loading rate (printing velocity), temperature, and solvent content on the ink transfer performance are addressed. Finally, the ink transfer mechanism is theoretically analyzed for different solvent contents using Surface Evolver. The calculation results are compared with those of the experiment.

Ultrafast Laser Engraving Method to Fabricate Gravure Plate for Printed Metal-Mesh Touch Panel

In order to engrave gravure plate with fine lines structures, conventional art used lithography with dry/wet etching. Lithography with dry/wet etching method allows to engrave lines with smooth concave shape, but its disadvantages include difficulty in controlling aspect ratio, high and uniform in large size process, substrate material limitation due to etching solution availability, and process complexity. We developed ultra-fast laser technology to directly engrave a stainless plate, a gravure plate, to be used for fabricating 23 in. metal-mesh touch panel by gravure offset printing process. The technology employs high energy pulse to ablate materials from a substrate. Because the ultra-fast laser pulse duration is shorter than the energy dissipation time between material lattices, there is no heating issue during the ablation process. Therefore, no volcano-type protrusion on the engraved line edges occurs, leading to good printing quality. After laser engraving, we then reduce surface roughness of the gravure plate using electro-polishing process. Diamond like carbon (DLC) coating layer is then added onto the surface to increase scratch resistance. We show that this procedure can fabricate gravure plate for gravure offset printing process with minimum printing linewidth 10.7 μm. A 23 in. metal-mesh pattern was printed using such gravure plate and fully functional touch panel was demonstrated in this work.

Effect of printing parameters on gravure patterning with conductive silver ink

Conductive line patterns were printed on a poly-dimethylsiloxane (PDMS) substrate using a gravure printing method with conductive silver ink. A plate-to-roll gravure print was prepared for this experiment. Gravure plates with fine lines 5–25 μm in width and 0–90° in tilted angles were fabricated using photolithography techniques. The printability, defined as the ratio of the real printed area to the ideal printed area, was measured and analyzed with respect to the process parameters and the line pattern designs. The effect of the process parameters on the fine line patterning was discussed, including the wiping condition, the printing pressure and the printing speed. The printability of the high adhesive substrate was examined by preparing a nanostructured PDMS substrate featuring a forest of 200 nm nanopillars using an anodic aluminum oxide (AAO) template. The patterns printed onto the nanostructured PDMS were compared with those printed on a flat PDMS substrate.

Screen-pad printing for electrode patterning on curvy surfaces

Pad printing is a simple but effective method for fabricating electrodes onto complex curved surfaces. In this method, ink is picked up from the gravure plate by the soft pad, after which the ink pattern is transcriptionally formed from the pad to the final substrate. However, this printing method has some problems; primarily, it is difficult to form thick and large patterns. To address these limitations, we developed a new printing technique called "screen-pad printing." In this technique, ink is first screen-printed onto a blanket made of silicone resin, after which the ink pattern is picked up by the soft pad, and the pattern on the pad is transferred to the substrate. In this paper, we describe the features of the developed screen-pad printing technique when forming patterns on objects that have complex surfaces. Further, the impact of our new method is analyzed by comparing the experimental results of screen-pad printing with results obtained from conventional pad printing.

Improving Gravure Plate-Making Method to Printing Transparent Conductive Film

The metal grid transparent conductive film is a kind of important electronic material. The production method is a valuable topic. Gravure printing, as one direct-printing method, is suitable for printing the metal grid transparent conductive film, according to gravure printing principle. This paper focuses on improving gravure plate to print the metal grid transparent conductive film. Firstly, the nano-sliver grid transparent conductive film is printed by electronic engraving plate and laser ablation plate. Then, according to the analysis result that the resistivity of the nano-sliver grid transparent conductive film printed by two general plates is too high to meet the requirements of the transparent conductive film, the general plate-making methods is improved to make the new gravure plate. Last, the metal grid transparent conductive film, with relatively high light transmittance and low resistivity which meet the requirements of the transparent conductive film , is printed by the improved plate.

Influence of Screen Ruling and Engraving Needle Tip Angle on Ink Transfer for Gravure

Gravure printing is widely applied in packaging printing and the ink transfer is very important for printing quality. Ink transfer affects the ink uniform, thickness and dot gain, so it is necessary to optimize the parameter of the gravure plate making. At present, some investigations are developed for the ink transfer only qualitatively. In this paper, the influence of screen ruling and engraving needle tip angle on ink transfer is researched experimentally. Firstly, the standard test gravure plate was prepared, and then the gravure plates are engraved at different parameter combining the screen ruling and engraving needle tip angle. Finally, the printing samples are obtained, from which the transfer amount and the density are measured. This paper, the amount of ink transfer and the density are investigated, and the results show that screen ruling and engraving needle tip angle affect the ink transfer amount.

Development of a gravure offset printing system for the printing electrodes of flat panel display

A gravure offset printing system composed of a roll-to-roll web-providing apparatus, a cup-type encapsulated doctoring blade, a flat gravure plate, and CCDs for line-width measurement has been devised for printing the electrodes of flat panel display (FPD) devices. This system may be characterized as a small experimental system capable of carrying out printing tests prior to using a huge gravure offset printing system for mass production. The conceptual design of this gravure offset printing system is focused on conducting the reliability accelerating test and on mimicking the huge mass-production printing process required for FPD parts such as plasma display panel electrodes. Using the fabricated prototype, printing experiments were repeated semi-automatically 300 times. It was found that it requires several bursts of idle printing for stabilization, that the widths of the printed pattern continue increasing little by little, and that the deviation in the width of the printed pattern increases as the number of printings is repeated. These increasing rates could constitute an index of printing reliability.

Pad printing as a film forming technique for polymer solar cells

Pad printing as a technique for preparing the active layer in polymer solar cells is presented. The technique employs a silicone rubber stamp to pick up the motif from a gravure plate and transfer it to the substrate. The strengths and limitations of pad printing are discussed and polymer solar cells prepared by pad printing are presented. Devices were prepared on indium tin oxide substrates but in principle the entire photovoltaic device comprising front and back electrodes, barrier layers and active layer could be printed with no need for vacuum steps. The device geometry comprises a spin coated transparent zinc oxide front electrode, a pad printed active layer based on a bulk heterojunction of the thermocleavable polymer poly(3-(2-methylhexyloxycarbonyl)thiophene-co-thiopene) (P3MHOCT) and zinc oxide nanoparticles, spin coated PEDOT:PSS and finally a manually cast thermally cured silver paste back electrode. The P3MHOCT was converted to poly(3-carboxy-dithiophene) (P3CT) in situ by heating the film to 200 ∘ C for a brief period. The entire printing and device preparation was carried out in the ambient atmosphere and the devices obtained had a good stability in air during storage and operation.

Simulation of liquid transfer between separating walls for modeling micro-gravure-offset printing

A numerical study of the liquid transfer processes that occur during micro-gravure-offset printing is carried out. Specifically, liquid transfer between two parallel separating plates and between a trapezoidal cavity and an upward moving plate are simulated, as models of the printing of ink from the offset pad onto the substrate and the picking up of ink from the gravure plate by the offset pad, respectively. During the liquid transfer between two parallel plates, the stretching, breaking and recoil of the liquid are illustrated, and the generation of a satellite droplet is observed. The influences of the separation velocity, liquid viscosity, surface tension, gravity force, and contact angles on the liquid transfer are estimated. For the transfer of liquid from the cavity to the upward moving plate, the findings indicate that the process can be divided into three stages: (1) a whole stretching stage; (2) a central stretching, breakup and recoil stage; and (3) an equilibrium stage. The final width of transferred liquid is closely related to the contact angle at the upper plate, while the cut height is mainly affected by the contact angle at the cavity side wall. The effects of the initial distance and cavity shape are also discussed.

Photopolymer Printing Surfaces for Gravure

AbstractA polyamide-type of commercial photopolymer was used to form a flexible gravure plate by exposure through a standard half-tone positive. The range of suitable exposures and resulting “etch” depths and cell volumes were determined. Comparisons with a theoretical model of cell volume were made. The plate was used to produce proofs whose densities were plotted against densities of the original. These results show that the variable depth-variable area cell obtained by the use of the 65° shoulder inherent in the polymer produces a final print density comparable with existing gravure systems.

Haniwa: The Clay Sculpture of Protohistoric Japan. By Miki Fumio. English adaptation by Roy Andrew Miller. Rutland: Charles E. Tuttle, 1960. 161. Color and Gravure Plates, Notes, Map with Key to Plates. $8.75.

Haniwa: The Clay Sculpture of Protohistoric Japan. By Miki Fumio. English adaptation by Roy Andrew Miller. Rutland: Charles E. Tuttle, 1960. 161. Color and Gravure Plates, Notes, Map with Key to Plates. $8.75.

Geographical Distribution of European Birds

Atlas of European Birds By Prof. K. H. Voous. Pp. 284 (419 maps and 355 gravure plates). (Edinburgh and London: Thomas Nelson and Sons, Ltd., 1960.) 70s. net.

Atlas of the Classical World. Edited by A. A. M. van der Heyden and H. H. Scullard. 14 × 10½. Pp. 222, including 73 maps in six colours, 475 gravure plates, and 24 pp. of index. London: Nelson, 1959. 70s.

Atlas of the Classical World. Edited by A. A. M. van der Heyden and H. H. Scullard. 14 × 10½. Pp. 222, including 73 maps in six colours, 475 gravure plates, and 24 pp. of index. London: Nelson, 1959. 70s. - Volume 40 Issue 1-2