Inkjet printers

Fig. 11-19. The drop ejection process in an inkjet printer (a) bubble nucleation (b) bubble growth and drop ejection (c) refill. [From J. H. Bohoiquez, B. P. Canfield, K. J. Courian, F. Drogo, C. A. E. Hall, C. L. Holstun, A. R. Scandalis, and M. E. Shepard, Hewlett-Packard J. 45(1), 9-17 (Feb. 1994). Copyright 1994, Hewlett-Packard Company. Reproduced with permission.]...

Inkjet printers are suitable in low-volume settings such as personal offices and the home. Inkjets provide low-cost color capability. Power use while the printer is idle is generally low, so that a distinct low-power mode is not needed. 

Ink jet printing is now the dominant non-impact printing technology. It has achieved this position from a platform of low cost, full color, very good (and ever improving) quality, and reasonable speed. For example, good quality color inkjet printers currently retail for ca. US 70, whereas the cheapest color laser printer costs ca. US 1,400 at the time of writing 43... 

The Chemical Inkjet Printer (ChIP), an inkjet printer-like device which is equipped with a piezoelectric reagent-dispensing system, has been developed by Shimadzu Corporation. The ChIP can dispense picoliter volumes of matrix solution onto a tissue section, which has four printing heads and nozzles that have no contact with the tissue section surface. 

Sakurai K, Teramura Y, Iwata H (2011) Cells immobilized on patterns printed in DNA by an inkjet printer. Biomaterials 32 3596-3602... 

In many processes (such as oil recovery, blood flow, underground water), one encounters liquid flow through thin (micrometer diameter), noncircular-shaped tubes, or pores. In the literature, one finds studies that address these latter systems. In another context of liquid drop formation, for example, in an inkjet nozzle, this technique falls under a class of scientifically challenging technology. The inkjet printer demands such quality that this branch of drop-on-demand technology is much in the realm of industrial research. All combustion engines are controlled by oil drop formation and evaporation characteristics. The important role of capillary forces is obvious in such systems. 

Over thousands of years for writing, the ancient people used naturally occurring colloidal fine material from ash (mostly charcoal) dispersed in oil (olive oil). Modem inkjet printers employing color are based on much more sophisticated components. Inkjet printers have a number of nozzles that inject ink droplets on the surface of paper. Simultaneously, different colors are mixed to obtain the desired color shade (more than hundreds of thousands). In a typical printer, there may be 30,000 injections per second, and there may be more than 500 nozzles (each with a size less than a human hair (pm =10 6 m). (The ink has a shelf life of more than a year.) In this process, the surface and colloidal principles most obvious are... 

Whereas gasoline is sold at large volume and low cost per pound, the ink for inkjet printers is sold in small volume at high cost per pound. It is a relatively new product that is riding on the crest of the information revolution, with great potential for growth and profit. Let us consider the marketing information needed in preparation for the introduction of a new product. 

The ink for inkjet printers is essentially colored water, and the current formulation of ink is about 75% water, plus dye and glue (Kang 1991, Le 1998, Pond 1999). The ink should flow readily from ihe inkwell to the nozzle, and then to the paper, without dripping or clogging. The viscosity of current inkjet ink is from 2 to 8 cP. The droplets formed should be very uniform in size, and should be as small as possible to increase the resolution. When the droplet hits the paper, the droplet should penetrate the fibers without splatter, which would increase the diameter of the dot on the printed text or picture. The surface tension of current ink is around 45 to 50 dynes/cm, which is much lower than water at 70 dynes/cm. It is believed that if the surface tension is raised from 45 to 65 dynes/cm, the spread (or ratio of diameter of spot on paper/diameter of droplet) would decrease from 3.3 to 1.1. Much higher resolutions... 

Increasingly there is a requirement for the printing of digital images in full colour. Whilst some progress has been claimed for direct thermal printing, e.g. the Thermo Autochrome from Fuji, the complexity of the multilayer papers means that they are very unlikely to ever compete effectively with inkjet printers. 

Inkjet printer ink PRO-JET see footnote Fuji Photo Film (Formerly Avecia), Japan... 

Examples of this trend are inks for inkjet printers. The pigments nsed are conventional Food Black 2 for black Direct Bine 199 for cyan a combination of Direct... 

Use a laser printer (as opposed to an inkjet printer, dot matrix printer, or a typewriter) to print any document you know is going to be scanned. 

Print your cover letter on a laser printer or high-quality inkjet printer. Using a standard typewriter will convey to the reader that you re not computer literate. 

The other piece of mandatory equipment that has changed recently is the data acquisition computer. Previously, every inexpensive HPLC had to have a strip chart recorder. The price differential between a computer-generated annotated chromatogram and a strip chart has dropped to the point that it doesn t make sense not to have that capability in the lab. You may only integrate 1 run out of 10, but when you need it, the capability will be there. Try and avoid a computer system using a thermal or inkjet printer. The paper does not store well for a permanent record. Often, it will be necessary to photocopy the keeper chromatograms for further reference and archival storage. 

Recently, the structurally related disazo dye 2 was developed for commercial thermal inkjet printers [3],... 

Full color printing is essentially the same as for black and white but requires four steps, one each for the yellow, magenta, cyan, and black toners needed for full color reproduction [2,3], Consequently, color laser printers and copiers are significantly more expensive than monochrome laser printers and especially inkjet printers. They are also slower than monochrome laser printers. 

Print the figure on clean, opaque, white paper, using a fresh ink or toner cartridge. Do not use a dot matrix printer. Set the laser or inkjet printer to a resolution of at least 600 ppi. 

There are examples of firms that have managed to survive a dismptive development by doing it themselves - but not many. One that comes to mind is HP (Hewlett Packard). HP pioneered the use of laser printers for personal use and managed to become market leader. It later picked up the idea of inkjet printers - a tmly dismptive idea. It is now also market leader in this area, with two divisions competing with each other. HP even kept the development of the new device separated from that of the regular business - by thousands of kilometres. There are other ways remember the story of the NovoPen ... 

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