Drop-on-demand inkjet printing

An inkjet printing of colloidal crystals was proposed by Frese et describing inkjet printing processes of monodispersed particles which are able to form two- or three-dimensional photonic crystals on the substrate surface by arranging in a closely packed lattice structure on the surface. The particle size was selected so that it will diffract light in the visible spectral region, i.e., particle size of 200-500 nanometers. In this work drop-on-demand inkjet printing techniques are utilized. 

Biehl et al. demonstrated a method to fabricate microlenses from hybrid organic-inorganic materials on glass using drop-on-demand inkjet printing with 50 /xm nozzles driven by piezoelectric... 

Planar lithography techniques are not effective for precise fabrication of microdevices with hemispherical shapes (17). Drop-on-demand inkjet printing of a photocurable ink is a more appropriate approach as it takes advantage of the surface tension as well as of the delivery of a well-defined ink volume. 

J. Krestschmer, C. Tille, and I. Ederer A drop-on demand inkjet printhead for a wide range of applications, IS Ts NIP 14 International Conference on Digital printing technologies, Seattle, pp. 343-347 (1997). 

Droplet radius, in polymer blends, 20 333 Droplet size correlations, 23 190-191 Droplet size distribution, in polymer blends, 20 332-333 Droplet sizes, in sprays, 23 185 Drop-on-demand (DOD) inkjet printing, 9 222... 

Drop-on-demand (DOD) inkjet is the method that is universally adopted in the printers used in the home and the office environments. It takes its generic name from the fact that ink is delivered from the ink head directly to the substrate only as demanded by the printing information supplied by the software. 

While all inkjet technologies can fundamentally be described as the digitally controlled ejection of drops of fluid from a print head onto a substrate, this is accomplished in a variety of ways. Industrial inkjet is broadly and most typically classified as either continuous (CIJ) or drop-on-demand (DOD), with variants within each classification. 

A further distinction, when referring to inkjet inks, is the printing mechanism. Solvent inks are used widely in drop-on-demand piezo inkjet printing (DOD PIJ) and in continuous inkjet (CIJ). To a lesser extent there is an effort to introduce solvents into thermal inkjet drop-on-demand (DOD TIJ). 

Inkjet is a non-contact additive process that delivers metered amounts of a variety of fluids at a precise location in time and space. It requires low viscosity liquid phase inks that must successfully be fired through a nozzle. Inkjet has broad appeal due to its seemingly simple nature. Although all inkjet processes share basic features, the ways in which inkjet technology can be configured are endless. For the most part, drop-on-demand printers have been used in inkjet printing of electronics. ... 

Derived from standard desktop printers, drop-on-demand techniques, such as electrohydrodynamic jet (e-jet) printing, solid freeform fabrication (SFF), or piezoelectric inkjet printing, are among a few notable examples of rapid prototyping techniques that have been developed to pattern biomaterials. With the incorporation of a user friendly computer interface, these techniques have been employed to process a number of multiplexed, biomaterial constructs without the use of masks, stamps, or any other time consuming processing equipment. The design of such constructs with minimal feature sizes in the microliter to picoliter resolution has been demonstrated and will be discussed below. 

The later developed thermal inkjet technology has the advantage of being able to position a drop on demand. Ink drops are not emitted continuously but only when needed for printing. This property eliminates the need for additional systems to capture and recirculate... 

When printing in the drop-on-demand mode employing certain inkjet ink compositions on substrates which retain high static electric charges, such as in poly(ethylene) and poly(vinyl chloride) shrink wrap packaging materials, the printer nozzle tends to clog up more frequently than normal (52). 

The transfer process of ink jet printing is one of removing a drop of liquid ink from the bulk and giving it a velocity of sufficient precision and magnitude to place it on a substrate in close proximity to but not touching the printhead. There are three broad techniques continuous, electrostatic, and drop on demand. Continuous inkjet printing, because of its intrinsic high drop rate, has tended to find more applications... 

As an alternative to the powder-based technologies. Inkjet Printing has been developed as a versatile process using liquid viscous materials. Inkjet printers can be further subdivided accordingly to the method of the delivering the material onto a moving build platform drop-on-demand and continuous jet. 

Inkjet printers can be operated in two different modes. One is continuous and the other is known as drop on demand (DoD). In continuous operation, connected structures are produced by a uniformly applied jet of ink. This mode is used primarily for high-speed printing. DoD, in contrast, produces a sequence of individual droplets of ink. Printing speed is limited, hut precision is much better than in continuous printing. 

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