Ink-jet technology

In contrast to writing, drawing, marking, and conventional printing methods, inkjet printing is a true primary, non-impact process. Liquid ink droplets are ejected from a nozzle under digital control and directed onto surfaces such as paper, plastics, metals, ceramics, and textiles to form a character or image [2,3], 

In the raster scan method each droplet can be charged individually and deflected to the substrate. Uncharged ink drops are collected and returned to the ink reservoir. 

The Hertz method [4] resembles the Sweet technology [4], since it also uses a continuous ink jet, the drops of which are charged by control electrodes. However, it uses charge intensity modulation instead of deflection and is especially suited for high resolution color printing. 

The impulse or drop-on-demand ink jet is a system of fundamental simplicity. It differs from continuous ink jet systems in two aspects (1) The image-forming ink droplets are not charged, so no deflection device is involved (2) Electrical signals are only used to control the moment when an individual droplet is needed. 

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Fig. 19. Ink-jet system (a) piezoelectric ink-jet firing chamber and (b) bubble formation ia thermal ink-jet technology.

Fig. 20. Growth in image quaUty of ink-jet technology, where corresponds to quaUty in 1995 for (-) continuous flow, (—...

Shibusawa, M. Kobayashi, M. Hanari, J. Sunohara, K. Ibaraki, N. 2003. A 17-inch WXGA full-color OLED display using the polymer ink jet technology. IEICE Trans. Electron., E86-C(ll) 2269-2274. 

Wallace, D. 1988. Automated Electronic Circuit Manufacturing using Ink-Jet Technology, Vol. 3. Division of Industrial Science and Technological Innovation (ISTI), Directorate for Scientific, Technological, and International Affairs (STIA), National Science, Washington, DC pp. 69. 

Hanson, E. 1999. Recent Progress in Ink Jet Technologies II. The Society for Imaging Science and Technology. 

Ink jet printing has become a major printing technology in desktop, commercial and industrial applications. The growth of ink-jet technology into these markets has been well documented [15], The reasons for this success can be attributed to the following factors ... 

In developing ink-jet printing devices a decisive task is associated with the formulation of inks. Basically, there are three types of ink-jet inks aqueous, solvent, and hot melt. The choice of ink depends on the ink-jet technology used. Aqueous... 

Ink-jet printing is a noncontact method the sample solution is dispensed without direct contact between the print head and the substrate. In modern ink-jet technology, a... 

The synthesis technology easily lends itself to miniaturization. Sol-gel processing can be adapted to ink-jet technology. The silica-like matrix which has been the most investigated is chemically, photochemically, electrochemically and thermally inert. 

This prevents water penetration and only the exterior of the electrode is exposed to electrolytes. When used with 30 nm sized carbon black powder, the conductive area of the electrode in contact with the electrolyte consists of less than 1 % of the geometric cross-sectional area of the electrode. This has been compared with an ensemble of microelectrodes. These CCEs showed an improvement of up to three orders of magnitude in terms of Faradaic signal-to-noise compared with glassy carbon electrodes [218]. In addition, the sol gel method of preparation affords a variety of structural configurations and it has been shown that CCEs can be produced by thick film and ink jet technology, which allows for their mass production [219]. 

Yeo, Y. Basaran, O.A. Park, K. A new process for making reservoir-type microcapsules using ink-jet technology and interfacial phase separation. J. Controlled Release 2003, 93 (2), 161-173. 

Since ink jet technology has not yet been used for high quality color reproduction, the objectives of this process must be considered in terms of the materials limitations of ink jet printing. When a color reproduction is made by a mechanical process, much time is spent matching different dyes and papers with the desired effect wanted. After the materials decision is made,... 

Looking into the past, the first microfluidic technology was developed in the early 1950s when efforts to dispense small amounts of liquids in the nanoliter and sub-nanoliter range were made, providing the basics of today s ink-jet technology [4]. In terms of fluid propulsion within microchannels with sub-millimeter cross sections, the year 1979 set a milestone when a miniaturized gas chromatograph (GC) was realized on a silicon (Si) wafer... 

The aim of HTS and UHTS is cost-effectiveness and speed of compound scanning. Hence, the robotics system not only has to deliver fast and accurate liquid samples into the wells, it has to be miniaturized to conserve the volumes required of the valuable samples and expensive assay reagents. For the 1536 wells, the liquids being dispensed are in the nanoliter (10-9 L) to picoliter (Kh12 L) range. The ink jet technology provided the technological basis for liquid dispensation in HTS. 

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