Recharger Magazine

Retail Inkjet Primer — Quality Inkjet Production and Fresh Virgins

• By Allen Luthy
• Nov 01, 2010

Note: This article is a synopsis of the author’s World Expo 2010 presentation entitled The Five Biggest Retail Inkjet Challenges Today. Recharger will run this as a three-part series. Part 2 follows.

Golden Monkey Black Tea? Double espresso? Energy drink? Unless you have a burning desire to learn more about processing quality inkjet cartridges in a retail inkjet environment as well as the nuances of the virgin inkjet empties market, some high-caffeine assistance might be in order to keep you from nodding off. Therefore, we will “mini-skirt” the topic: Include enough material to cover the basics but keep it short enough to make things interesting. Sound fun? Let’s begin.

When inkjet cartridges were first refilled in the late 1980s there wasn’t much to the process — drill small hole, refill ink with syringe, cover hole, repackage, sell. Fairly simple. However, as cartridges evolved, so did the complexities of cleaning and refilling them.

Industrial inkjet background

Someone touring a large-scale industrial inkjet remanufacturing operation today would be very likely to see a wide array of quirky gadgets and Rube Goldberg production equipment including atomizers, vacuum boilers, vacuum chambers, vacuum ovens, clothing-grade washers and dryers, steam guns, ultrasonic baths, ultrasonic welders, ink degassers, deionized water tanks, pressure pots, centrifuges, overflow flushers, forced- air foam dryers, “hot rooms,” and electrical testing stations.

The primary reason why all of this is required is that in an industrial environment the cartridges processed are typically not fresh — “fresh” meaning that the cartridge has only been out of the printer for a few weeks and there is still residual ink on the print head of the cartridge that will leave an ink “footprint” if touched to paper. The fresher the cartridge, the easier it is to refill. Industrial operations typically only acquire the empty cartridges after the remaining ink inside has long dried up, and aggressive processing is required to recover them.

Another reason is economy of scale: Industrial batch processing typically averages seven to 10 cartridges per man hour, while smaller-scale retail operations can achieve three to five cartridges per hour in batch mode. All-in-one systems typically average two to three cartridges processed per man hour. Industrial operations have production lines of expensive dedicated equipment with limited switchovers (processing only one cartridge type for hours before switching equipment settings to a new type). Cartridge types are run in large batches and the process is automated as often as possible. The profitability of an industrial inkjet operation is to a large degree tied to the price of acquiring the empty cartridge.

Retail ink plusses/problems

In the retail inkjet market the empty cartridges are generally fresh, free and readily available. That is all wonderful. The downside to processing cartridges in this environment is that there typically is not enough space and specialized equipment to do a thorough job. Couple that with limited air, water and waste options and in most cases batch processing is not an option. Therefore most retail inkjet operations only process the fresh cartridges. Those that suffer from hubris (very common in our industry) and attempt to remanufacture every non-fresh empty thermal inkjet cartridge (virgin or not) often run into difficulties and end up with boxes of thousands of dollars’ worth of “unrecoverable” cartridges.

The four most common problems remanufacturing thermal inkjet cartridges include:

1. Cleaning of the print head

2. Cleaning the ink delivery channels

3. Priming the cartridge

4. Electrical and recognition issues (this will be covered in Part 3 of this series).

Cleaning the print heads

When a refilled cartridge exhibits streaky printing (“banding”), a likely reason is that the cartridge print head and nozzle areas are blocked by dried ink. We don’t have the time to cover the topic of kogation (look it up) and what is actually happening inside the firing chambers of the cartridge, but we can discuss the best cleaning methods. Soaking a cartridge print head overnight in one of the many available cleaning solutions is generally always a great way to begin any cartridge cleaning process. Heated atomization cleaning with psi of 70-plus seems to work best to “pressure-wash” the print head, but steam cleaning works well too. Ultrasonic baths are very good as well but some frequencies and extended use can destroy a cartridge, so research before using.

Cleaning the ink delivery channels

No amount of “babying” can help recover a completely dried-out inkjet cartridge (especially the black pigmented ink varieties). Dye-based ink cartridges (generally color) are easier to rehydrate but once the pigments inside the black cartridge coagulate only an aggressive deep cleaning will get the ink flowing through the cartridge again. Some of the older Lexmark black cartridges exhibited the legendary “shoe polish” inside the barrel portion of the cartridge and the only viable option was to completely disassemble the cartridge in order to clean and refill it.

Deep cleaning is not really a viable option in a retail environment without compact specialized equipment. The two most popular methods are overflow flush cleaning with hot pressurized purified water (uses copious amounts of water) and vacuum boiling (uses much less water but many more changeovers and flushings). Both methods work well, but unless the foam cores are properly dried afterwards the cartridge will not work well once refilled. For example, pockets of water or cleaning solution left inside a cartridge will negatively interact with the new ink, and wet saturated foam cores cause a number of other problems. Therefore, centrifuges, forced air foam dryers, food dehydrators, small vacuum ovens, or just time are all ways to dry out the cartridge prior to refilling.

Refilling and priming the cartridge

The ultimate goal of a refilled cartridge is to perform just like a brand-new OEM version in both print quality and page yield. A cartridge can have double the amount of ink of its brand-new counterpart, but if the ink isn’t flowing properly after it has been installed into the printer, the consumer rejects it. Most problems like this are attributed to air during the refilling process and a failure to properly prime and test the cartridge.

For example, refilling an HP 45/15 cartridge is fairly simple. I met a man who successfully refilled one more than 30 times. However, if the air in the Mylar bladder of the cartridge is not evacuated after the refill, even this aftermarket all-star cartridge will not work.

Processing the thermal inkjet cartridges with polyurethane foam cores can be very convoluted and problematic. With zone back pressure, non-useable ink, poor capillary flow, de-primed jets, hydrophilic/hydrophobic foams, color contamination, etc., there is too much ground to cover with the limited space available. (For an in-depth explanation of the inner workings of the foam-core thermal inkjet cartridges and the importance of refilling them in a deep vacuum chamber, see “Brassieres and Inkjet Cartridges?” Recharger Magazine, May 2010). Given that there are dozens of different styles of inkjet cartridges and 50 different methods of refilling them, here are some bullet-proof axioms:

• Air is the Achilles heel of inkjet remanufacturing
• Syringe refilling cannot achieve OEM page yields
• Non-vacuum chamber refilled cartridges don’t handle pressure/elevation changes well
• Deep vacuum chamber refilling consistently offers the best results

Fresh virgin empties

Most industrial remanufacturers only process virgin cartridges. Why? The yield gain offsets the cost savings using non-virgin cores. This is one reason why virgin empties are priced at a premium. Cartridge collections are especially important to this market segment because of the variable and often fluctuating costs of the empties. The OEMs have been doing a great job over the past two years of raising the cost of empties by removing the refillable cartridges from the marketplace.

Retail inkjet businesses customers generally bring in fresh empty cartridges right out of their printer to be refilled (topped off). Since roughly 10 to 13 percent of cartridges are either electrically or mechanically defective, another core has to be available for refilling. Collecting empty cartridges makes great business sense: It is a necessity to have spare virgin cartridges on hand, there are more opportunities to interact with potential prospects/customers, and collecting empties can become an excellent additional revenue stream.

Part 3 of this three-part series on retail inkjet refilling, discussing Technical Hindrances, Printer Driver Hell, and Outsource or Upgrade? will run in the Recharger December 2010 issue.

Contact Allen Luthy at allenluthy@hunterhouseamericas.com.

This article originally appeared in the November 2010 issue of Recharger.