Mon, 26 Jun 2000

Good ink and media give fine results

By Zatni Arbi

JAKARTA (JP): I was enjoying the ride in his white Fiat Uno when my friend, Happy, raised the classic question, "Can it really harm my printer if I use a refilled cartridge?"

Happy runs a fast-growing graphic design business. It's no surprise then that he and his eight employees churn out a lot of printed color graphics and images every day. Perhaps, to cut corners, someone suggested that he try using refilled cartridges.

The issue of using refilled cartridges is by no means a fresh one and I've written about this issue a couple of times in this column. But it just so happens that a week earlier I had been on an HP Asia Press Tour focusing on ink and print media technology. During the two hour event entitled "The Heart of the Matter", I learned quite a few interesting things about the technology that can perhaps shed some more light on the debate.

Determining factors

First of all, how does an inkjet printer work? The ink -- color or black -- is stored in an ink tank. The print head, the part of the tank that faces the printing paper, has a large number of nozzles. Each of these nozzles is perhaps smaller than a human hair (about 70 microns in diameter), and there are hundreds of them in one row.

The large number of nozzles is needed to increase the print resolution -- the number of dots that a printer can print in a square inch area. Currently, 2400 dots per inch (DPI) seems to be the highest resolution level on the market. The more nozzles a printer head has, the more ink drops it can eject onto the paper in one pass, and the faster the printing process will be.

"Nowadays we're talking about 136 nozzles per cartridge," Paul Anthony, HP's Consumer Supplies Business Manager for Asia Pacific explained to the room full of Asian IT journalists.

A fast printer should be able to squirt up to 7.3 million ink drops per second. That's certainly rapid firing but clearly the ink should meet very stringent requirements to avoid clogging the nozzles.

In the ink itself, certain microorganisms may grow and affect the thickness of the ink over time. What we may have been unaware of is that HP has been adding a specific biocide to the ink to prevent microbial growth, and this has enabled the company to guarantee the functionality of their ink cartridges even months after the expiry date.

Today's ink should also dry quickly. My four-year-old DeskJet 1600C, for example, has a heating element inside it, and when the paper comes out of the printer it always feels warm. The heater heats the paper so the ink dries as soon as it hits the surface. Today, if you look at the DeskJet 970Cxi for example, there is no heater. That's because today's improved ink can dry quickly without the need of a heater.

Consideration of the environment is also of growing importance.

"We guarantee that our ink is not poisonous. If, by any chance, you happen to ingest the ink, you'll not be harmed in any way," claimed Rob Beeson, HP team leader of the Global Competitive Intelligence Team.

Well, why should I think of drinking the ink, which at Rp 200.000,00 for 40 cc is far more expensive than my favorite orange juice? Still, at least it helps the environment if the cartridges ever end up in landfills.

A final but no less important factor is the interaction between the ink and the service station in each printer. When you turn on an inkjet printer, you will notice a noise coming from the right side of the machine. Actually it's a process in which the rubber service station cleans the print head to remove ink residue.

"Because they may contain alcohol, refill inks may damage the rubber part of the service station over time," explained Rob. Interestingly, Rob's job includes analyzing their competitors' so-called "aftermarket" supplies.

There are other characteristics of the inks that are also important. Viscosity is one of them. Viscosity is important because ink can spread and follow the contours of the paper. HP uses water as a solvent which has a very low viscosity.

Photo requirements

"The first inkjet printer was launched in 1988," recalled Rob, who has been in the printer technology field since 1984. "At that time, the target was to enable inkjet printers to produce laser- quality text print.

The target has been achieved, although the quality of the laser printer has also improved a lot. Now our target is to enable users to print photos as high in quality as the ones using silver halides."

There are a number of specifications involved in achieving this target. Resolution alone is not the only factor that determines the quality of the printout.

First, the ink should have bleed control. What this means is that when several drops of a certain color ink are placed next to several drops of black ink of ink of another color, the two colors should not merge.

Next, the printer's inks should have the capability to produce the largest color gamut -- different shades of colors seen in a 3-D table. In the past, a dye-based ink had a better gamut than the pigment-based ink that the newer generations of HP printers have been using. However, further technological development has enabled the printer to produce an equally rich color gamut.

Another requirement for photo printers is fade-resistance. If you look again at the photos that you took a decade ago, you'll notice that some are fading. This is inevitable, as even we fade with time. The objective, however, is to prevent photos printed with home printers from losing their lightfastness too quickly. This is achieved by, among other things, applying a special coating to the surface of the paper.

Talking about coated paper will probably remind you of my article on the Canon BJC-8200 Photo Printer two weeks ago, when I underscored the need to use special paper for the best photo print results.

"The coating helps manage the ink as it hits the paper," explained Rob.

However, because the coating also interacts with the ink, and each printer vendor has its own proprietary inks, it is best to use the same brand of photo paper for the printer that you use.

"There is a low cost generic photo printer made in Japan, but it may not give you the maximum results," he added.

The glossy or matte coating on the photo paper also gives it a true photo feel, which is an increasingly important feature in digital photography.

Different geographies obviously have different climactic characteristics, and humidity can also affect the absorption of ink by the paper. "In order to cater to the needs of people who live in the more humid areas, we have just introduced a special photo paper for the Asia Pacific that will compensate for humidity," Paul informed us.

Now, how important is the ink and the print head mechanism in determining the overall performance of the printer?

"Eighty five percent of the quality of the print is determined by the ink and the cartridge," said Paul. "The ink is like the blood, and the cartridge is the heart of the printing system," he added.

Contrary to what we may have thought, HP works on ink and cartridge technology first before starting to design the printers that will use it. In fact, the three top printer makers -- HP, Epson and Canon -- spend billions of dollars researching ink technologies alone. In the case of HP, the ultimate goal is to enable their printers to print photo quality images on plain paper.

Well then, how much is the contribution of the ink supply sales to HP's overall revenues? HP is not willing to disclose the figure, but if we think of how much the prices of inkjet printers have dropped in the past few years, we can draw our own conclusions. To recover the cost of making the bait and all the research activities, the profit from ink sales must be pretty high.

Yet, if we take into consideration the details involved in making the ink, perhaps it is also clear that we should use authentic ink if we want to get the best results, avoid untimely damage to our printers and help minimize the impact on the environment. Now the question is, how can you still save on ink consumption?

As I have repeatedly suggested, set the printer on its most economical mode which is the default print mode. Switch to the highest quality only when you need to print the final copy of your masterpiece -- or the photos that you want to show around. (