Part I: What Choices Are Out There?
Because of the impact printers have on our resources, from the consumables they use, to the business models being adopted by the manufacturers of the hardware, I will be writing about printers in several entries to come. The first segment, today, is a general overview of printer technologies and the nature of the printer market today. In future entries, I will be dealing with several of the printing technologies in use today, there benefits and pitfalls, what we can do to lessen our environmental footprint with those technologies, and where the future may lead us in the next several years.
Printers: a very necessary evil?
Long before computers, there were methods of reproducing paper documents. Early in our industrialization, they were the only method of distributing information other than word of mouth (the town crier), and in spite of all the great advances in communications, such as telegraph, radio, television, satellite and the internet, what has remained constant or grown in importance is paper document communication. Today, we produce more paper documents than ever in history. That’s due to the forever lowering cost of hard copy production, the increasing consumer global marketplace, and the fact that every home has one or more printing devices accessible to us.
In spite of talk of the paperless society, we are still heavily invested in paper printout. Our species is tactile in nature. We like to touch and handle things in the physical world. Paper is cheap and easy mobile, readable, and easy to annotate. But on of the main reasons for the failure of the paperless world to date is that other forms of storage are not yet trustworthy. In some cases, our legal system has not accepted electronic documents as legitimate, and the equipment involved for reading electronic documents is still bulky, costly, not as suited to our vision as reflective paper, and requires electric power, limiting access.
So, for now, we are still heavily invested in paper documents. Since this blog is addressed to mainly non-commercial and home computer users, I won’t go into the many multi-thousand dollar printing devices out there which are used in commercial printing facilities, but instead narrow this discussion to those printers used in the office and home environment.
Until recently, an easy distinction could be made between strictly business and text printers versus artistic and photographic output products. That line has blurred considerably with fast inkjet printers producing clear text, and color laser printers producing near-photographic image quality. Today, most printers are multi-function. In fact, many have now incorporated scanners, fax machines, and other abilities into printers, making the devices more complex and of more concern when it comes to discarding or replacing them.
Multi-function products have two principal advantages. One is their physical footprint is usually reduced from the space that would be required for several separate devices, and secondly, the multi-function units tend to be less costly than a group of individual dedicated units. However, that is where the advantage usually ends. The disadvantages are that should one function fail, it often leaves all the other functions unavailable. Further, if you need to ship the unit in for repair, you lose access to the other features until the unit is returned, and if the unit needs replacement, the cost of replacement may be more than just a dedicated device. From a design standpoint, multi-function products by their nature must be made less durable to keep size, weight and costs down. These considerations make them more likely to fail, and more difficult to repair, and should you wish to upgrade due to one feature set becoming obsolete, the whole unit is usually discarded. Therefore, in general, dedicated products are more durable, have more features within their individual functionality, last longer and are easier to repair.
Before dealing with what can be done to lower the environmental "footprint" of our printers, I’d like to offer a review of the field of products out there. Several of the products listed below are available as both dedicated printer models, as well as the so-called "all in one" or multi-function products which often include scanners, fax machines, and copier functions.
Black and White Printers:
The earliest computer-interfaced printers were daisy wheel and dot matrix models. Daisy wheel printer (named for the daisy flower shaped wheel which had a text character moulded into each petal of the "flower" and which spun around and impacted onto a ribbon) were basically electric typewriters which were redesigned to talk to computers.
Dot matrix printers use a series of pins which fire and impact a ribbon and paper in patterns to make letters and symbols. While daisy wheel printers have pretty much become obsolete, dot matrix printers are still in use today. Their main advantage, besides very low consumable costs, are that they do not require specialized paper, and due to their ability to impact the paper, they can be used with multi-part forms with carbon paper or carbonless chemically treated papers. They can handle up to 5 part forms, can work with continuous forms or paper, or unusual paper lengths. Their main disadvantages are they are slow and noisy, do not produce high quality output (neither in terms of resolution nor levels of grey scale), and they are typically used with preprinted forms and may become out of alignment or registration with the form, making things difficult to read. They tend to be quite durable and their main cost is a usually cloth ribbon.
Yet another black and white technology still used today for point of sale and cash registers and some fax machines, is thermal printing. This technology requires a heat sensitive chemically coated paper which is heated and which darkens when activated by a hot pin of a print head. Again, this technology is principally for text printing. It’s main advantage is that it is quiet, relatively fast, and the mechanism is small and doesn’t use much power. The main disadvantage is the paper required is chemically treated, doesn’t recycle particularly well, and the document is vulnerable to fading or darkening with heat.
Finally, there is laser technology, which is also used in photocopiers. Briefly, these devices create defined electrostatic fields on a drum or belt which then attracts a very fine dust made up of pigment, dyes, wax and resins (called toner). That powder is then transferred to a sheet of paper by transferring the static charge and finally the paper is passed through some heated rollers (the fuser) which melt the powder to the paper.
The advantages of this system are that the printing is fast, especially for multiple copies, the printer can print on numerous types of untreated paper, on both sides. The image is relatively permanent, and inexpensive. The resolution can be excellent for text and newer models can produce enough grayscale levels to print black and white photographic quality images. The image is waterproof and fadeproof.
The main disadvantage is the amount of waste involving the consumables. There are at least drums or belts that wear out, toner cartridges that may not be refillable, and sometimes developer units and waste toner jars required. I will get into more detail about the ways to avoid some of those pitfall in another blog entry in the future.
At one time, inkjet printers were also exclusively black and white. Today, all models provide color and black printing, so I will discuss them in the next section on color printer.
Color Printing Tecnologies:
The color printer market is much faster growing than that of the black and white. Fifteen years ago, prior to color inkjet technology, the cost of a color printer was prohibitive to all but commercial printer services. Then came the color inkjet and the world changed.
As mentioned, early inkjet printers were black ink only. They were slow, tended to be unreliable, clogged easily, and were often messy to work with. The output would smear, and fade, and the resolution was mediocre. That all began to change when Epson introduced a different technology for propelling the ink drops to the page. Continued competition in the inkjet market advanced the technology forward, more nozzles per head meant faster output, and eventually head production cost was lowered and made having multiple heads in one printer economical, allowing for color to be introduced. Over time, smaller and more controlled dots, better ink formulations, and specialized papers allowed inkjet technology to become the best photographic output available in computer printers and at a very reasonable cost. Those technologies differ based upon brand and age of the printer. The two basic technologies are referred to as thermal and piezo head design. Thermal inkjet heads heat the ink in a small tube momentarily, just enough to boil the ink and propel a drop out of the end of the tube and to the paper. Piezo heads use a vibrating quartz device which works like a small pump by changing dimensions with electrical charge. The piezo method has allowed for a wide variety of inks types to be run through inkjet printers.
Inkjet printers should have been the great environmental answer to printing. Lower quality output can be printed on basic bond papers, while high quality printing can be accomplished on specialty papers. Cost of ink is low, and the formulations can be changed for different applications, including using pigment colorant ink for fine art and permanent output, and, in theory, the printers can be built long lasting, with nearly permanent heads, and the ink cartridge could be refilled, leaving almost no waste behind.
Unfortunately, theory and profit motive conflicted completely. More on that to come in part two of this series.
The advantages of inkjet printers are that they only use their inks where required in the print. They need little resource, like internal memory, many can work with roll paper, and wider carriage versions don’t require a lot more technology or weight than the smaller desktop models.
The disadvantages are the need for special paper for high quality output, wasted ink due to the cleaning cycles to maintain the heads from clogs, and the fade potential and water solubility for certain ink formulations. And, a profit driver decision to confound cartridge refilling.
Yet another color technology is so-called "dye-sublimation". This technology is poor for text printing, because it produces relatively low resolution dots with soft edged, but the variety of colors it can produce is very wide, up to 16 million colors, allowing it to produce quality photographic output.
This technology involves a panel of mylar film coated with dye, the dimensions of the final print, for each color used. Typically that means 3-5 panels of dye per print, usually on a continuous roll. Each set of panels is used only once, for one print. The printed image is produced on a specialized receiver paper, usually with a glossy surface. The printers uses a heated head that produce a great variety of heat levels to vaporize the dye on the mylar and it transfers to the closely positioned receiver paper which has a special surface. The process is relatively slow and the machines are typically quite noisy. The main problems are waste and cost. The special paper is costly as are the dye panels. The paper is limited in size to that of the color panel sizes. The printer itself is usually rather costly, rather large for larger format output, and they rarely support output larger than about 11" x 16".
I’ve already discussed the basic mechanics and issues with laser printing technology in the black and white area. Color laser printers are just an expanded version of black and white laser, using the same technology but usually having four color toner cartridges; cyan, magenta, yellow and black, with much greater amounts of consumables and waste.
The last color printing technology I’d like to discuss is a lessen known one. Solid ink printers are a unique design, originally produced by Tektronix Corporation. This technology was later sold to Xerox, which now manufactures and distributes these printers. The printers use a colored waxlike ink which is heated into a liquid and then sprayed onto the paper surface. These printers use 4 colors of ink, cyan, magenta, yellow and black. Solid Ink printers have some interesting characteristics that make them a useful niche technology. Years ago, this technology was rather crude, and the dots were fairly large, making them of little value for photo-like imagery, which left this technology to business graphics and text. In more recent times, the dot size has been decreased to the point that something approaching photo quality can be reproduced. These printers are fast, can print on many surfaces since the ink and wax cling well to the surface of materials, including some plastic sheets. The cost per print is rather low due to the inexpensive nature of the color consumables. The other advantage of these printers is since the ink doesn’t require a lot of packaging for transport (they are usually just in a simple plastic package) and the delivery system to the printer mechanism only involves the melting of the solid ink with heat, so no cartridges or complex devices are required. Also, the distribution process of this waxy ink is relatively simple, somewhat like inkjet printers. Unlike laser printers, no optically or electrostatic sensitive drums are needed. All this means minimal consumables, which has some environmental and economic advantages.
However these printers are not without some disadvantages, as well. There design requires them to be relatively large, and they are noisy due to the highly mechanical nature of the printing process. Since the inks need to be made liquid by heating, these printers work best if left on all the time, although they can be left in a relative sleep mode to reduce energy requirements. If the printer is shut down, it requires a process of reheating and a purging of the heads to clear out the cooled inks, which causes a loss of consumables.
The inks themselves are waterproof since they are waxed based, but they are usually colored with dyes, which can fade in bright lighting and may crack off the surface of some materials if the printed surface is manipulated. The surface of the printed area, being waxy, cannot easily be written to, and the ink can transfer to other surfaces if the paper gets heated or abraded against something. Lastly, these pages cannot be laminated or coated, again due to their waxy nature.
Obviously, this print output is not for production of fine art images or for documents which will be handed regularly, However, for low number mass reproduction, such as short term advertising, this printing methods may provide a good economic alternative to other color printing methods.
What’s Next?
This ends my general overview of the currently available home and small office printer technologies, their basic operation, and under what purposes they are best suited. In the next segment, I will discuss the major problem with the business models being used by printer manufacturers and what you can do to get around them. In that segment, I will explain why today’s computer printers have so much in common with razor blades of old and why it is not a good thing for economics or the environment.
