In the past five years, a very strange situation has developed in the market for home and office printers. On the one hand, there are several large manufacturers that regularly update lineups and seriously competing with each other. On the other hand, there is absolutely nothing for an IT journalist to write about their struggle. The business press can juggle a little bit with market shares and other boring things. And our man, having looked more closely at the "new" models, immediately notices that from a technical point of view, no serious improvements are observed in them. Rather, on the contrary - in parallel with the addition of various embellishments, such as high-definition LCD screens, the actual printing part is being simplified.

First of all, of course, this applies to inkjet printers where progress stopped in the middle of this decade. I find it hard to believe it myself, but even HP, which once led the race to increase the number of ink tanks in photo printers, today considers using just four colors sufficient. Four! This is after NINE in the older models of HP Photosmart five years ago! Four inkwells in those days were considered acceptable only for very simple models, where photo printing is not the main function. Epson still has eight-color models, but they have been produced for the second five years already (for example, the eight-color Epson R800 went on sale back in 2004), new products do not cross the six-color barrier. Yes, and according to the main characteristics, somehow print resolution and drop size, Epson printers and MFPs have not gone ahead over the past five years. Take a look at the characteristics of laser devices - they also have not changed for a long time, both in black and white and in color models. So why did the industry, which was developing so rapidly at the beginning of the century, pick up and “slow down”?

Blame, of course, the marketers of printer manufacturers. At the turn of the century, when digital cameras entered the mass market, they suddenly decided that this was their chance. Like, since citizens now do not have to go to the laboratories to develop the film, they themselves will prefer to print the photographs at home, and not at someone else's uncle. If so, they should ensure the quality of the minilab right on the desktop ahead of time. The market for photo printers seemed huge, and a lot of money was invested in R&D, both in inkjet and laser directions. It was planned that inkjet printers would live at home, and laser photo printers (and such were being developed) would be actively bought up by companies that use high-quality pictures in their work (ie, from real estate agencies to mail-order stores).

At first, everything went fine: people, by inertia, continued to print photographs on paper, because it seemed to be accepted that way. But then suddenly the understanding came that, it turns out, the pictures look good on the computer screen, but there are mobile phones, laptops, digital photo frames, smart players, etc. etc. And for carrying them over long distances, they are better suited optical media, flash drives and e-mail. As computer equipment mastered by pensioners, the last hope of manufacturers of photo printers, the demand for really high-quality printing at home or office environment. All that citizens really wanted was to print quickly and, most importantly, cheaper. Well, if where some shade is not accurately transferred, it’s not scary. And even those who continued to print photos on paper still rushed to minilabs, where the price of a print is one and a half to two times cheaper than that made at home, especially when it comes to large formats.

As a result, printer manufacturers have received very advanced printing technologies with no chance of recouping their development costs in the planned time frame. Resigned and realizing that the existing backlog in terms of picture quality would last for a long time, everyone switched to increasing the speed of printing and reducing the price of both the devices themselves and the prints. An equally important direction of modernization was the damage to the lives of manufacturers of so-called compatible cartridges and toner, which prevented them from recouping at least the price of the device itself. The development of new, alternative printing technologies, if not stopped, then slowed down significantly. And then the global financial crisis began ...

This long introduction is written so that you understand the harsh conditions under which Xerox is trying to market solid state ink MFPs, which are radically different from both inkjet and laser printers.

Solid on the outside, liquid on the inside

The idea of ​​using solid consumables in printers has been on the minds of developers for a long time, and among the companies where it came to at least pre-prototypes are Howtek, Exxon, Dataproducts, Hitachi, Spectra and Brother. The most successful were the experiences of the American company Tektronix, which in 1986 patented the printing technology with solid ink (Solid Ink), and in 1991 began selling the world's first color printer where this technology was used.

I printed the Tektronix Phaser III on Letter-sized paper (slightly smaller than A4 we are used to), and it took about two minutes per sheet. Considering that we are talking about a full-color print of a very decent quality for those times, the speed could be called very acceptable. But the price - $ 10,000 - made many think (for comparison, a black-and-white laser printer in those days cost around $ 2,400). Plus, the first implementation of the technology left much to be desired. After all, the ink remained solid only until it got inside the printer. There, solid sticks, consisting of a mixture of wax, toner and vegetable oils, turn into a liquid with a temperature of more than a hundred degrees. on paper, and therefore, for users who were too lazy to take care of the correct fastening, printers jumped around offices like mad washing machines. When installing on the table, it was necessary to choose a thicker tree, and fasten the legs to the floor with self-tapping screws. In fact, the print speed, which was not high by our standards, was precisely due to the need to constantly accelerate and decelerate the heavy head. There was no way to guarantee accurate reproduction of shades even within a single print. Due to the peculiarities of the technology, it was impossible to follow the order in which drops of ink of different colors hit the paper. For example, if yellow was applied first, and then purple, the red hue turned out to be somewhat different than when yellow was applied over purple. Add to that the lingering smell of either a candle factory or an artist's workshop in the room where the printer was used, and you'll understand why Tektronix's solid-state ink business didn't do well.

Despite the difficulties, Tektronix continued to develop the technology, and the engineers achieved considerable success, which, however, did not allow the Color Printing and Imaging division to achieve acceptable financial performance. In 2000, it was sold to Xerox Corporation along with all the patents and the Phaser trademark. Today, the corporation produces devices that print on A4 and A3 paper. Despite the differences in exterior and dimensions, they are arranged very similarly, and they intricately combine jet and offset technology print.

So, today the print head is stationary, and it generally does not come into contact with the surface of the paper. Printing is carried out on a rotating drum made of anodized aluminum, which before each cycle is cleaned of ink residue and covered with a thin layer of silicone grease. The width of the head repeats the width of the drum, and has an operating temperature of 135 degrees Celsius, while the drum itself only warms up to 65 degrees. Ink, falling on the drum, instantly thickens and fixes on its surface. When the head (which, given its size, one would like to call head) finishes work, a slightly heated sheet appears in the tray, it is pressed against the drum with a special roller, and in one pass the entire image is transferred to paper. The ink layer is very thin, and the paper is almost cold, so no additional operations are required to fix the print.

Due to the relative simplicity of technology and a minimum of moving elements in the design, the print speed in the older XeroxColorQube models reaches 85 A4 color prints per minute! Yes, the younger ones give out up to 60 pages, which, you see, is also not bad at all. Considering that ink practically does not interact with paper, you can print enough high quality photos even on ordinary office papers. Moreover, thanks to the wax base, they will shine like the pages of glossy magazines. Due to the high "tenacity" of the ink and the low heating of the media, it is possible to print on films and even on foil - the main thing is to choose more or less dense samples. The engineers also managed to overcome the problem of smell: modern models are quite neutral in this parameter. If you remember that the price of a color print on a printer with solid state ink is half that of a laser one, it is worth asking the question: why hasn't Xerox-Tektronix technology conquered the entire market yet?

Little nothings of life

Briquettes of solid-state ink look nice and even appetizing - probably not in vain in the mid-nineties, the president of Tektronix bit off and ate a piece of such an "ink" at one of the presentations. To avoid confusion, each color has its own shape, and therefore it is almost impossible to set the bar in the wrong place by mistake (unless, to undermine it with a file or crumble it).

They do not melt in the hands, they treat drops during transportation with understanding, the shelf life is practically unlimited, you can load from 3 to 6 briquettes of each color at the same time, depending on the model. An important nuance: after installation in the printer, the user is left with only a small box made of recyclable plastic. For residents of the States and Western Europe, this is a very serious advantage compared to cartridges with ink or, even worse, toner. In general, such printers have few consumables: only the ink itself and the cleaning module, which also contains silicone grease. Everything else, from the head to the drum, will last at least five years (the head life is at least a million prints), and, if necessary, can also be replaced. Although, most likely, it will be easier to buy a new model by then.

But here we come to the first disharmony. Once in the tank, combined with the print head, the ink turns from solid to liquid, and should remain so until it hits paper or other media. While waiting for use, they are kept at a temperature that does not allow freezing, and as long as the printer is plugged in, everything is almost fine. Almost - because electricity is consumed to heat the ink. But if someone turns the printer off or the power goes out, the ink will dry out and become unusable. The next time you turn on the printer, they will warm up and merge them into a special waste tray. In large A3 printers, the losses will be relatively small, around 4% of the volume of one briquette, but in relatively portable models (due to design features, printers with solid-state ink cannot yet be completely compact), where the bars are much smaller, up to 20% is consumed, and this is already much more serious. Such features of the technology are very disliked by users and serve as an object of ridicule for competitors.

On the left is the waste ink tray, on the right is the cleaning module

The second disharmony lies in the slow start of printing. More precisely, if the ink is warmed up to the desired level, the first page comes out of the printer almost instantly. But keeping them constantly perfectly liquid is too expensive, so when the printer is “sleeping”, they are kept in a fairly thick state, saving energy. The “wake-up” time is up to fifteen minutes, and this, to put it mildly, is not very advantageous against the background of laser solutions . Xerox engineers figured out how to get around the problem: a freshly installed printing device carefully studies the behavior of its owners for two weeks, and determines when it is necessary to be in full readiness, and when it is possible to take a nap. I did not check it myself, but Xerox says that the system works quite efficiently, and the solid ink printer consumes no more than its laser colleague with similar characteristics per circle. So, in new models, power consumption in sleep mode does not exceed 50 W, and this is really a little against the background of general office costs.

Prints at first look very impressive: juicy shades, smooth color transitions, glossy shine. But, by running a fingernail or the back of a fountain pen across the picture, you will certainly leave a strip on it - the wax is very gentle, and is not prepared for mechanical stress. Moreover, the higher the print quality and, accordingly, the thicker the ink layer, the “softer” the print. Laminating it is also categorically not recommended: from the high temperature in the laminator, the wax will simply spread in all directions. Also, do not print solid state printer blanks, such as letterheads or certificates of honor, which then have to go through a laser printer: it is too hot in a laser for waxing.

The list of technology disharmony is closed by the increased sensitivity of printing devices to external influences. So, if the printer or MFP gets a strong enough push (who knows what fantasies office workers will have?), or they want to move it without waiting thirty minutes from the moment it was completely turned off, splashing of ink can occur (remember the temperature of 125 degrees) with extremely unpleasant consequences for internal parts . This type of damage is easily calculable and is not covered under warranty.

Success against all odds?

The first Xerox models with solid ink printing technology were accepted by the market rather reservedly. Firstly, they lacked shortcomings, and, secondly, competitors made a fuss in time and organized a powerful campaign in the best traditions of black PR. Until now, on Youtube you can find surprisingly high-quality and funny videos (rumor ascribes their authorship to HP) about the unlucky system administrator Karl, who installed a Xerox printer in the office and daily scolds for it the full program from colleagues and superiors. Printers smell bad, turn off spontaneously, spoil the ink - in general, if you are interested, do a search for "Carl Xerox solid ink". I especially don't like Xerox white bear, whose protection Karl is so concerned about.

But in 2009, a new line of ColorQube was released, supporting the A3 format and consisting of three models, 9201, 9202 and 9203. Outwardly, they look the same, and differ only in performance. So, if in black-and-white mode the print speed for the whole trinity is the same, from 38 to 85 A4 pages per minute, then in color the peak speed is 60, 70 and 85 A4 pages per minute, respectively. Otherwise, full similarity: 512MB random access memory, hard drive 80 GB, four gradations of print quality with a resolution of 600x600 DPI, fax, scanner with automatic document feeder and a host of options, from a saddle stitch finisher to a two-line fax.

And these office MFPs, unexpectedly for many, "shot", they began to snap up like hot cakes, and there is still a certain shortage of Xerox ColorQube in the American market. Not quite the same as on the iPhone4, but still quite tangible, given that the price of the younger model starts at $22,500. Agree, the figure is quite impressive for spontaneous shopping.

There seem to be two reasons for the success. Firstly, the next incarnation of Xerox solid ink technology got rid of very obvious shortcomings, such as a 20 percent loss of usable ink volume when turned off and an unpleasant smell. More precisely, the same amount of ink is lost, just the bars have become larger, but purely psychologically 4% are perceived easier than 20%.

Secondly, in developed countries, devices of this class are usually not bought, but leased, and payment is often based on the number of prints, divided into color and black and white. And when companies offer to choose between several devices with similar characteristics, but on only one color printing costs almost half the price ... In general, you understand. Plus, unlike laser devices, there is no strict division into color and black-and-white prints: the area occupied by a color image is calculated, and if it is a small logo, the price of printing a particular document may practically not increase.

By the way, the appearance of compatible briquettes can serve as indirect evidence of the popularity of new MFPs. True, Xerox does not recommend using them for obvious reasons, but those who have tried them do not write terrible things on the forums. In no case do I urge you to use clones, you just need to understand that Chinese craftsmen rarely clone consumables of completely “dead” products.

Solid Answer

Despite all the limitations of solid ink technology, I sincerely want to wish her success. If players of the caliber of Xerox and HP start a serious battle, it certainly won't hurt consumers.

Just keep in mind that solid-state ink will not appear soon, if at all, in home printing devices. This is a technology for large volumes of printing, and at home, where most of the time printers and MFPs work as dust collectors, it has nothing to do. Nevertheless, if you want to be original, you can buy the cheapest of the "solid state" - Xerox Phaser 8560. It prints up to 30 A4 pages per minute (no matter black and white or color), costs from 35,000 rubles, and a set of briquettes for 1000 sheets will cost about 3300 rubles.

About which I only recently learned to my shame, then let me tell you about one "new" for me personally.

If you ask a random person about what printers are, he will immediately answer: inkjet and laser. The older generation will remember more matrix devices - but this will all end. In fact, there are a number of other technologies, and one of them has serious advantages over the others listed.

We are talking about solid ink printers. Who knew about these?

The history of solid ink printing began in the mid-1980s, when the first printers based on this principle appeared. They entered the market in 1991, but the truly unusual technology was revealed only ten years later, when Xerox engineers took up its development. They faced a non-trivial task - to make an unusual technology so inexpensive and simple as to fully reveal its benefits.

How is a solid ink printer different from the usual inkjet and laser printers? An inkjet printer forms an image from multi-colored dots, which are applied by a print head - a matrix with liquid dyes. The picture is clear, with good halftone reproduction, but the inkjet works rather slowly, and the image comes out unstable, prone to fading, blurring or erasing. The laser printer uses xerography; dry ink (toner) is distributed over the drum, which is rolled over the paper. Then the resulting print is fixed by heat treatment. "Laser" works quite quickly, but the print quality of color halftone images (such as photographs) is lower than with inkjet printing.

In addition, new laser printer cartridges are quite expensive, in some cases almost reaching the cost of the device itself. Solid ink printing combines the characteristics of known technologies, while avoiding their shortcomings. To refuel such a printer, not expensive consumable cartridges to be disposed of are used, but ... ink briquettes! That is, the consumable is such in full, leaving nothing superfluous behind. In addition, the design of the solid ink printer minimizes the number of moving parts, which reduces wear by dozens of times. How does this device work?

Drums and rollers

Simply put, the solid ink circuit includes only four elements - a fixed ink loader (the bars are melted in it), a print head, an aluminum drum on which the image is applied and from where it is transferred to a sheet of paper, and a lubricating roller designed to apply silicone lubricant to the surface drum. This scheme is, one might say, a "hybrid" of inkjet and laser, and at the same time includes some features offset printing. At the same time, solid ink printers were originally intended for color printing - unlike their "parents", who survived the evolution from monochrome to color.

Fact number 1. The first solid ink printers printed quite slowly, at a speed of about 1 page per minute. The print speed of modern devices reaches 30 ppm.

Briquettes of four colors (classic CMYK), similar in consistency to candle wax, are inserted into the receiving compartments of the printer - that is, into the ink loader. As needed, they melt, touching one end with a heating plate, and are fed into the print head reservoirs. Interestingly, the Xerox company came up with "shape coding": each bar, in addition to color, has a different shape, it cannot be inserted into someone else's "nest". You can report the bars even during printing - the head itself and the receiving windows are separated. The bars, by the way, are made of a resin-based polymer and something similar to chalk (of course, the exact formula is kept secret) - they are non-toxic and biodegradable. Meanwhile, the print head, equipped with special nozzles, delivers molten ink to a rotating drum coated with silicone oil. The drum is about twice as cool as the head (65° vs. 135°) and the ink thickens. During printing, the transfer roller is pressed against the drum - the paper falls just into the gap between the drum and the roller. The adhesion between the drum and the ink is extremely small - and the latter stick to the paper in a given sequence, where they finally solidify. It would seem that everything is perfect. But there are reasons why solid ink printers are ideal for some industries and not entirely profitable for others.

Advantages and disadvantages

In principle, we have already talked about the advantages: almost complete waste-free printing, simplicity of design and, consequently, durability, low cost of operation, high speed work. There is one more plus - the print quality does not decrease with time (even for laser printers, photoconductors wear out, but here there is no such problem). In addition, the print colors are bright, like those of expensive "laser printers", and a solid ink printer can print on any paper - even on newsprint, even on cardboard, as long as the sheet sags under the drum. And due to the low temperature of the roller and drum, there are no jams due to material sticking to the shafts - the eternal disease of "laser"! - it can't be here.

Fact number 2. About 90% of municipal solid waste in Russia is not destroyed, but is disposed of. About 40 million tons of municipal solid waste is generated annually in the country, and almost all of this volume is placed in landfills, authorized and unauthorized landfills. Against this background, the use of solid ink printers with their minimal use of consumables is a significant contribution to the environmental situation in the country and the world.

Nevertheless, waste is still present in the printer, even if it is 30 times less than that of a laser competitor. The fact is that when the printer is turned off, the melted ink that enters the head solidifies again. And they do not withstand repeated melting - the consistency and color change; you have to "drain" what has already been melted and frozen. This process takes a lot of time - starting the printer from an idle state can take up to 5-10 minutes, so it is recommended to unplug it from the outlet as little as possible. This is easy to do in the office, but not always convenient at home, and with small print volumes, once a week does not make sense at all. The second point is the durability of the ink. Although the solid ink printer adopted the print speed from the "laser printer", and you can't wash off the prints with water, their mechanical strength is rather low. Simply put, the print can be scraped off or broken with a strong crease - you can’t do this with a “laser”.

Fact #3. Solid ink does not get dirty, just like candle wax does not get dirty. This distinguishes solid ink technology from the use of toner cartridges.

All these factors allow solid ink printers to fit perfectly into almost any niche where you need fast and high-quality printing at a minimum of costs and consumables. For example, it is difficult to come up with something better for working with documents, graphs and tables, so the technology has found wide application in the business sector, in offices, exchanges, enterprises and, in general, among users who print a lot of documents. Today solid ink printing is the know-how of Xerox. The company is constantly improving the technology, gradually conquering an increasing segment of office printing. The technology is used, among other things, by the latest models of the company's MFPs - Xerox ColorQube 8580/8880 and ColorQube 8900. Solid ink printing is not a technology of the future in the sense that it is actively used in the present. But the segment of its use is naturally growing, because useful inventions cannot remain in the shadows for a long time.

Benefits of solid ink technology

Low equipment wear, durability and reliability;
- ease of replacement and low cost of consumables;
- almost complete absence of waste;
- high speed printing;
- resistance of prints to blurring;
- the ability to print on a wide range of materials.

Disadvantages of solid ink technology

The instability of prints to physical influences and high temperatures;
- high duration of start after disconnection from the network;
- disposal of frozen ink after disconnection from the network.

sources

Reducing the cost of technology has led to the fact that color printing in recent times became more and more popular, therefore, the demand for color printers increased.

About the benefits of color

In addition, color reduces the time it takes to find the right information by 80%, reduces the number of errors, for example, when filling out questionnaires, and even encourages the buyer to pay the invoice in full if it is clearly highlighted in the document. Finally, color plays an important role in brand awareness.

Solid ink technology

Currently, there are two main technologies that are used in desktop color printers: laser and inkjet. A variation of laser technology is LED printing. Solid ink technology is closer to inkjet in principle, but it has its own characteristics. Sometimes it is also called sublimation, but this is not entirely true.

The solid ink system is a rather interesting solution, which is an invention of Tektronix. In 2000, a division of this company and the rights to all developments were acquired by the technology giant Xerox. He currently produces two lines of solid ink printers: Phaser and ColorQube. By the way, there are no black-and-white printers that use pigment ink in briquettes. This technology originally developed for color printing.

The process of operation of a solid ink printer is as follows: when the device is turned on, solid dyes are heated in special containers to a temperature of +60 ° C and, in a molten (viscous) form, are fed to a fixed piezo-jet print head. The diameter of the holes through which the melted ink is fed is comparable in size to the thickness of a human hair. This provides excellent image quality!

Then, a mirror image of the future print is formed on the heated surface of the transfer roller, and then, with the participation of a pressure roller, by pressing the dye, it is transferred to the paper medium. On paper, the ink dries instantly, producing a durable and vibrant final print.

Since the circumference of the transfer drum is the same as the length of the paper, the image is transferred in one pass. This provides a fairly high print speed. For example: many modern color laser printers use 4-pass technology, so they print quite slowly.

Solid ink printers use special inks in briquettes (sticks) of four primary colors corresponding to the CMYK scheme: cyan, magenta, yellow and black. The stick of each color has a specific shape, which prevents errors during ink loading. You can load consumables into the printer at any time, even without interrupting the printing process.

Solid ink printers are most widely used in offices where there is a need to print a large number documents in color.

Benefits of solid ink printers

Solid ink technology is based on the principles of inkjet printing, which is known to produce higher quality images than laser printers.

Prints created with the XEROX Phaser or ColorQube feature bright, vibrant colors, high fill density, and a glossy finish. The print quality does not deteriorate even when the printer is used for a long time.

Due to the absence of exposure to very high temperatures, thick paper, cardboard, films, and even plastic can be used as print media for solid ink printers.

At the same time, solid ink printers are more primitive (in good sense of this word) designs of laser printing devices containing many elements that one after another fail and fail and require replacement. The minimum number of moving components and parts ensures maximum reliability of the equipment. Therefore, solid ink printers require repairs much less often, and their operating time before replacing the drum is about 5 years.

Disadvantages of solid ink printers

Unfortunately, when operating a solid ink printer, it is almost impossible to avoid wastage of consumables. The melted ink must be in a liquid state until it is completely used up, because once it solidifies again, it can no longer provide excellent image quality.

In this regard, the solid ink printer must be constantly connected to the network, and this is an additional power consumption. If this is not possible, before starting work, the machine melts the solidified ink and pours them into a special container for waste materials.

The second disadvantage of solid ink is the instability of prints obtained with their help to physical and thermal effects. Since this dye is a waxy substance, the image is easily damaged by accidental scratching, especially if it is applied to glossy paper, peeling off after being under pressure for a long time (for example, if the sheet lies in the middle of a stack of documents), and also “floats” in direct sunlight .

For the same reason, prints obtained on a solid ink printer can only be laminated at t + 100-115 ° C. Under the influence of higher temperatures, the dye melts.

And finally, to the question of economy. Prices for XEROX Phaser and ColorQube printers initially seem quite high. Reducing the cost of printing is only possible through the purchase and use of alternative consumables.

In contact with

Classmates

Solid ink for printer are solid-state dyes used in inkjet printing.

Solid ink was developed in 1986 by Tektronix, and in 2000 the rights to all developments in the field of solid ink printing were purchased by Xerox. Currently, solid ink printing is used in Xerox product lines such as Phaser and ColorQube.

After the user submits a job for printing, part of the ink briquettes melts and changes from a solid to a liquid state. The melted ink enters the printer's print head, then onto a rotating drum coated with silicone grease, and from there onto a heated sheet of paper. The image is transferred in a single pass, making solid ink printers print very quickly.

Some authors classify solid ink as a type of sublimation ink, but this is fundamentally not true. Sublimation ink for the printer during the printing process passes from a liquid state to a solid state, and then to a gaseous state, and solid ink from solid to liquid, and in this form is applied to paper.

The transition of solid and sublimation ink and one state to another

Solid ink cartridges are available in standard CMYK colors (cyan, magenta, yellow and black).

Xerox Solid Ink Standard CMYK Colors

The table shows the most common Xerox solid ink options.

Xerox Solid Ink Options

Xerox ink sticks come in a variety of cross-sections and serial numbers from "1" to "4", which allows users to accurately determine the order in which they are inserted into the printer. The top of the cartridge is marked with an arrow ““”.

Xerox Solid Ink Sticks are uniquely shaped and labeled for easy installation into the printer.

A significant advantage of solid inks over liquid inks and toners is the fact that they can be loaded into the printer at the time of printing.

Considering that solid inks contain polymeric additives and wax, they are perfectly fixed on almost any type of media, including fabrics made of coarse fibers.

Prints made with solid inks are comparable in contrast and brightness to prints made with oil or water-based paints, and are only slightly inferior in durability to pigment inks. They are absolutely resistant to moisture, but fade under the influence of direct sunlight. Therefore, when used in an open environment, such images should be laminated with a special film. Regular film will not protect solid ink prints from fading, and they will very soon lose their brightness and attractiveness in the sun. This feature of solid ink should be taken into account when printing materials intended for outdoor placement, such as street advertising.

The figure below shows a comparison of two solid ink prints that have been exposed to the sun for 4 weeks. The print shown on the left side of the figure was protected with a special laminate, and the print shown on the right side was protected with a conventional laminate.

Comparison of solid ink prints coated with a special (left) and conventional (right) laminate

Laminating solid ink prints with a special film allows you to extend their life cycle.

The advantages and disadvantages of solid ink are listed in the table.

Advantages and disadvantages of solid ink

Solid printer ink is capable of applying high-quality images to any surface, including paper of various densities, cardboard, film, and fabrics. Wax, which is part of solid inks, gives them gloss, provides brightness and saturation of prints, uniformity of filling. The ink sticks do not melt in your hands, do not disperse in the air like dry toner, and do not spread like liquid ink. They are safe for environment and human health, as they are made from plant materials and oils.

Solid ink printing technology was invented in 1986 by Tektronix, primarily for publishing and printing needs. Released in 1991, the company's first solid ink printer, the Phaser III, cost about $10,000 and was intended primarily for printing color proofs. Further improvement of the technology made it possible to improve the quality of printing and bring the price of printers to values ​​acceptable for ordinary office printing. Since Xerox's acquisition of Tektronix's printer division in 2000, this business has continued to grow. It is important that, unlike laser solid ink technology, it was originally focused on color rather than black and white printing. In fact, it is closer to inkjet, but with elements of laser and even offset: the drops of molten dyes ejected by the nozzles of the head do not fall directly on the paper, but first on a heated metal drum, from which they are already transferred to the paper, where they freeze. This achieves, on the one hand, the high print speed inherent in laser printers, and on the other hand, the quality of image output, approaching offset printing.

Operating principle

"Ink" in its original state are small sticks of wax-like composition mixed with a dye in one of the four primary printing colors - cyan, magenta, yellow and black (CMYK). Note that the colors of the bars bear little resemblance to those obtained after they are melted - for example, the “blue” bar looks dark blue (almost black), and the “purple” looks dark brown. A bar of each color has a unique (distinguishing it not only from bars of other colors, but also from bars for other models of solid ink printers) a bizarre shape corresponding to the shape of the hole in the compartment of the ink container intended for it. This "form coding" almost completely eliminates the possibility of an error when refilling the printer with ink. Up to four bars are “charged” into each compartment, and you can add them at any time, including during the printing process. When closing the lid of the container, the bars are pressed by springs so that the head bar in each compartment is firmly pressed against the ceramic melting plate.

The ink melted by the hot plates flows into the heated reservoirs of the print head, where it is maintained in a molten state. After filling a tank of a certain color, the corresponding melting plate is turned off. As the ink is used up, the plates turn on, maintaining the required level of dyes in the head reservoirs.

The stainless steel piezo inkjet head has 1236 nozzles and, unlike inkjet printer heads, covers the entire width of the printed page. The resolution of 2400 dpi achieved in modern models of solid ink printers is provided by a small (to the distance between adjacent nozzles) horizontal movement of the head. The piezo elements of the nozzles are capable of ejecting up to 30 million drops per second. Thanks to this design, the print speed is much higher than that of inkjet printers (up to 30 ppm).

Drops of dyes ejected by the head fall on a rotating stainless steel drum heated to a temperature lower than the head, on which a thin layer of silicone oil is previously applied using a special roller, which is part of the maintenance kit. On the drum, the dyes pass from a liquid to an intermediate elastic state.

When about a third of the page image is formed on the drum, a sheet of paper (or other media) is fed from the lower paper cassette or multi-purpose front tray. After passing through the heater slot, the heated sheet is pressed by the transfer roller against the drum, and the dyes, which have greater adhesion to the paper than to the oiled smooth drum, pass onto the sheet, where they finally solidify. The scraper included in the maintenance kit cleans the drum of dirt and dye drops remaining on it, after which the process is repeated.

As you can see, the printing technology is practically waste-free. However, the figure shows a node about which nothing has been said so far - a waste tray. Where do they come from? Waste is generated when the printer is ready to be used from a cold (i.e. completely turned off) state. One of the stages of this long (up to 15 minutes) process is the vacuum cleaning of the head nozzles, in which part of the melted ink is drained into a waste container and solidifies there. That is why it is recommended that a solid ink printer never be turned off. With frequent shutdowns, a quite noticeable part of the dyes can go to waste, so in the case of an unstable power supply, you should consider purchasing a separate UPS for the printer.

The printer controller (in the latest Xerox models, it is based on a 600-MHz RISC PowerPC processor) provides image rasterization (the main page description language is PostScript 3, PCL5c emulation is also possible) and control of the print engine. The control panel, printer driver and PC communication interfaces do not differ much from laser models.

Advantages

A solid ink printer has a number of undeniable advantages over a color laser printer. As already mentioned, they are largely due to the fact that solid ink technology was originally developed with an eye on color printing, while a color laser printer is actually four monochromes in one package.

The main advantage of a solid ink printer is a much simpler design, a disproportionately smaller number of mechanical, optical and electronic components and hence higher reliability. It does not have a precision optical-mechanical system for scanning the laser beam, nor photoreceptors, nor blocks for developing and thermally fixing the image. If a laser printer (even a monochrome one) that has worked its entire service life with a rated load and has never been repaired is almost impossible to find, then for a solid ink printer, if used correctly, this situation is quite real.

The second most important advantage is a much smaller number of consumables and the ease of adding and replacing them. There are only two such materials - ink sticks and a maintenance kit. The ink is in a solid state, does not stain hands and clothes, it is extremely easy to add - even a child can do it. Solid ink technology is also unique in the sense that dyes can be added without interrupting the printing process. Replacing the maintenance kit is also a simple operation, taking less than a minute.

The third, also important, advantage is stable print quality, which does not change over time and does not depend on the number of pages printed on the printer. With virtually all color laser printers, print quality will noticeably deteriorate as image drums, transfer rollers, and other parts wear out.

In terms of print quality, bright, vivid colors can be noted, which only high-end color laser printers can boast of, costing several times more than solid ink, or inkjet models when printing on specially coated paper. The advantage of a solid ink printer over the latter is the absence of ink spreading on any type of paper, up to newsprint. There is absolutely no “striping” characteristic of many laser (and some inkjet) printers. The prints are waterproof.

Last but not least is the high print speed (up to 30 ppm), which is typical only for much more expensive models of color laser printers, while the cost of a solid ink printer is close to the cost of a monochrome network laser printer of similar performance. Such a short first page out time - 5 s - is a record value not only for color, but also for monochrome laser models.

Laser printers typically have two sheets of paper in the paper path at the same time to achieve maximum print speed, which is the cause of most paper jam problems. In a solid ink printer, the next sheet always starts feeding after full exit the previous one. With a simpler paper path, solid ink printers can print on heavier media than most laser printers - up to 220gsm. They have no problem printing on a wide variety of media - recycled paper, envelopes, transparencies, media of varying thicknesses and types of media (such as envelopes with a transparent window). Due to the lack of fusing toner, solid ink printing can use media that is more sensitive to heat than laser media.

Last but not least for anyone who cares about the environment, the benefit is 90% less waste than laser printers. For clarity, we can cite the following figures: after printing 100 thousand sheets on a color laser printer of a similar class HP LaserJet 4700, 71 kg of waste is generated, while on a solid-ink Xerox Phaser 8560 - only 2 kg.

disadvantages

As often happens, the disadvantages of solid ink printing technology - flip side her merits. First of all, they are due to the fact that the ink is in a solid state at room temperature, and the constant readiness of the printer for printing involves maintaining them in a molten form.

The biggest drawback - a very long "cold start" compared to other types of printers (in the first samples of Tektronix, the initial start-up time reached 45 minutes, in modern models it is reduced to 12-15 minutes) - it will not be very noticeable if you never turn it off network printer. At the same time, the second drawback is leveled - a significant consumption of ink for the initial start.

Even if the printer does not turn off completely, but is in an energy-saving state (note that this concept itself has a slightly different meaning for solid ink printers than for laser ones - if for the latter the consumption in this mode is usually less than 20–40 W, then for the first it is more 200 W), the time of its preparation for work after the arrival of a print job is 4-5 minutes. It is clear that in most office applications such a delay is unacceptable, therefore, special methods are used to ensure that the printer is always ready - automatically turning on and off according to a schedule, and even automatically tracking the “printing” behavior of employees and turning on the printer shortly before the start of periods of activity (turning on and off here means switching to active and power-saving modes, respectively).

Now about prints. Their main drawback is their low mechanical strength (solid color fills are easily scratched with a fingernail). The obvious defense important documents- lamination, but pitfalls lie in wait here too - due to heating in the laminator, thin lines and small fonts are slightly blurred. Another drawback is associated with the lack of mixing and spreading of ink on paper and the low density of nozzles in the head. As a result, in the light areas of the photographic images, a "point" noticeable to the naked eye is observed. This disadvantage makes it practically impossible to use the printer for high-quality photo printing. His element is text and business graphics with not too thin lines and solid color fills.

Economic indicators

As you know, the most important technical and economic indicator of a printer for medium workgroups (namely, Xerox solid ink models belong to this category) is the total cost of ownership (TCO), calculated taking into account all costs over the life of the printer.

Let's try to roughly calculate this figure for laser and solid ink printers with similar performance and maximum monthly load - Xerox Phaser 6360DN and Xerox Phaser 8560DN. However, we will not take into account the cost of repairs and Maintenance devices, which, in view of the foregoing, will play into the hands laser printer. We will not take into account the cost of electricity - here the solid ink machine already wins. We will start from a realistic estimate for printers of this class of the average number of printed pages over the entire life of color pages (with 5% coverage for each of the four colors) - 300 thousand. The number of consumables of each type was calculated by dividing this figure by the resource of the corresponding material declared by the manufacturer with rounding up.

As you can see, in terms of total cost of ownership, a solid ink printer even surpasses a laser one. An additional economic benefit of a solid ink printer is less downtime due to repairs and lower maintenance and repair costs.