Thermal ink-jet printer

Black Dyes. Water-soluble black ink jet dyes are selected from disazo, polyazo, metal complex, and sulfur dyes [7], For ink-jet systems using the piezo technology, C.I. Direct Black 19, 35255 [6428-31-5] and DirectBlack 154,303865 [54804-85-2 are used. Food Black 2, 27755 [.2118-39-0] was selected for thermal ink-jet printers due to its thermal stability, but this dye exhibits a poor waterfastness. Replacing the sulfo groups by carboxyl groups gave C.I. DirectBlack 195 (1), which has been introduced in commercial printers and shows much improved waterfastness due to pH-dependant differential solubility [3],... 

In many commercially available demand-mode ink-jet systems today, a thin-film resistor is substituted for the piezoelectric transducer. When high current is passed through this resistor, the ink in contact with it is vaporized, forming a bubble over the resistor [17]. This vapor bubble serves the same function as the piezoelectric transducer. This t5rpe of printer is referred to as a thermal ink-jet printer. 

W. Runge Nucleation in thermal ink-jet printers, IS T s Eighth International Congress on Advances in Non-Impacting Technologies, Springfield, 299-302 (1992). 

Office. Various segments of the office market have the largest population of computers, and thus the greatest demand for computer printers. In 1994, however, more computers were purchased for home use than for the office. The fastest developing computer printer technology is thermal ink jet, whether measured by rates of performance increase, price decrease, or purchase. 

Over the past 30 or 40 years many technologies have attempted to take a share of the imaging market, particularly that for nonimpact printing [1], Of these technologies, two now dominate, namely, laser printers and especially ink-jet printers, although thermal printers are also used, particularly in color printing. 

Newer uses for anilines include as high performance engineering plastics and organic semiconductors, and for traditional aniline pigments in dye diffusion thermal transfer (D2T2) and the photorealistic ink jet printer. 

MEMS find wide applications in microsensors such as acoustic waves, biomedical, chemical, inertia, optical, pressure, radiation, and thermal microactuators like valves, pumps, and microfluidics electrical and optical relays and switches grippers tweezers and tongs as well as linear and rotary motors, etc., in various fields. They also find application in microdevice components such as palmtop reconnaissance aircrafts, minirobots and toys, microsurgical and mobile telecom equipment, read/ write heads in computer storage systems, as well as ink-jet printer heads [4]. 

Thermal Bubble Nucleation The growth and collapse of a microbubble via a microheater actuator, with the applications to ink-jet printers, have been studied extensively in the decades. It has been demonstrated that the pressure inside the bubble could reach several MPa during the initial bubble growth period, with the heating duration of within several microseconds. It should be highlighted that most... 

Devices employing the vaporization of superheated fluid are known concurrently as thermal ink jet or bubble jet printers, the choice of name depending on the manufacturer. Since drop on demand ink jets rely on capillary refiU, their operational frequencies are much lower than for continuous ink jet devices. This stresses the importance of the compactness of the actuating system so as to achieve reasonable printing speeds via multiple nozzle printheads. The nozzles must also be precisely registered with respect to each other if systematic print artifacts are to be avoided. 

There are two types of impulse printers (Eig. 19). A piezoelectric ink jet propels a drop by flexing one or more walls of the firing chamber to decrease rapidly the volume of the firing chamber. This causes a pressure pulse and forces out a drop of ink. The flexing wall is either a piezoelectric crystal or a diaphragm driven by a piezoelectric incorporated into the firing chamber (Eig. 19a). Thermal impulse ink jets also propel one drop at a time, but these use rapid bubble formation to force part of the ink in a firing chamber out the orifice (Eig. 19b). 

Generally, ink dyes for ink jet applications and writing, drawing, or marking materials are selected from food, acid, direct, sulfur, and reactive dyes. The choice of dye depends on the application and the ink used, whether it is aqueous, solvent based, or hot melt, and on the printer type continuous ink jet or drop-on-demand, piezo or thermal inkjet. 

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