Even when standards are in place, yield information should be referred to with care

July 31 - Aug 06, 2006

It is not surprising that printer users often ask as to why they have to pay so much for ink. What they might don't know is that with advances in printing technology, printer manufacturers like HP are able to build ink-saving designs that allow users to print more pages with less ink compared to just a few years ago. In addition, inkjet ink is not "just ink" in the same way a commodity item like sugar is "just sugar", where you buy it by weight. A significant amount of R&D goes into creating the ink, optimizing it for various printer and paper technologies so as to produce reliable and high-quality prints.

So rather than focussing on how much ink per cartridge you're getting for your buck - or the cost per millilitre (ml) of printer ink - it's more useful for buyers to consider the concept of page yield, according to HP sources in a media briefing held recently.

Page yield looks at the number of pages a cartridge actually prints. This is a more meaningful way of calculating cost - per page instead of per ml.

Page yield depends on a variety of factors but there exists an ISO standard for monochrome laser toner page yield that HP supports. The factors listed under this ISO/IEC 19752 standard include the test document, print job size, print quality modes, end-of-life determination, sample size and environmental conditions.

Although standards have not been established for inkjet cartridges and printers, HP is working very closely with the SIO to finalise them.

Yet even when standards are in place, yield information should be referred to with care. For example, all inkjet printers use some ink before printing begins if the printer has not been used in a while or when a new cartridge is installed, to keep the ink flowing smoothly and the nozzles clear. Some printers use a lot of ink for this process, while others use very little. The less ink used for this process, the more ink is saved for printing and the higher the "printing efficiency".

Published inkjet cartridge yields quoted are typically measured by printing continuously until the cartridge is empty. The proposed ISO standard also uses continuous printing. Since there is no beak in printing, the ink used between jobs in everyday printing is not considered. As a result, yield standards provide a useful baseline for comparing products but do not give a complete picture.

Actual page yields will depend on the printer model, how it has been optimized, as well as what and how often you print, which relates to printing efficiency.

In efficiency tests by US-based SpencerLab Digital Colour Laboratory, HP printers tests show the highest efficiency (printing up to twice as many pages as competing printers with the same amount of ink) and the smallest percentage change in page yields between continuous printing and intermittent printing - thanks to ink saving technologies. This includes patented non-crusting ink formulations designed to work with the cartridge and printer to reduce nozzle cleaning. In contrast, competing brand yields dropped significantly (www.hp.com/apac/saveink).

That is why in addition to yield, buyers should consider all factors like reliability, productivity, quality and efficiency to get the best overall value from their printing system. Because after all, products that work reliably and efficiently save time and expense in the long run.