WIMS (White Ink Management System) is not actually new but it has been redeveloped so dramatically that it may as well be, says Tony Whitmore. WIMS agitates and circulates the white ink. White ink is essential to the process of direct to product ink jet printing if you want to print onto anything other than white fabric, explains Whitmore. "Just as with screen printing, the coloured ink needs a white base to stand against otherwise the white areas of a design would be the colour of the fabric.

"Manufacturing white ink is difficult to say the least but now it exists there is a certain amount of housekeeping that must be done."

The pigment used in the ink is manufactured from Titanium Dioxide (Tio2) and is heavy. As it is suspended in a water-based binder, it is therefore likely to sink or settle. If left to its own devices this will have a serious effect on the quality of the print and can also result in problems with the machine as the sediment forms in the ink reservoir and, worse still, the print head, dampers and supply pipes.

"The manual way around this was, and still is with other machines, to shake the bottle and, if the machine is not worked frequently, to regularly draw ink through the system," continues Whitmore. "To alleviate this DTG came up with WIMS, which continually agitated the ink and also automatically conducted regular head cleans. This in itself was quite a breakthrough as it meant that the machine could be left for a few days without the worry of the ink system clogging up.

"But this was not enough for YES or DTG, who set about furthering the development of the system to make it more user friendly and cost effective. Say hello to the all new WIMS," says Whitmore.

Head cleaning on ink jet printers has always been a cause for complaint because of the amount of ink used, says Whitmore. When an ink jet printer goes into a cleaning cycle all it is doing is forcing ink through the system. With the standard four colours of cyan, magenta, yellow and black you are only drawing ink through one set of nozzles but with the white ink it could be four or even eight sets, thus multiplying the amount of ink used in the cleaning process.

The new WIMS uses special pumps and filters to recycle the white ink so the actual loss is negligible. On a standard machine a cleaning cycle will use up to 5ml of white ink and, to maintain good housekeeping and print quality, you would need to do about five head cleans in 24 hours, so that's 25ml per day. Multiply that by days and weeks and the annual saving on white ink using the new WIMS system is very profitable, says Whitmore.

Another feature of the new WIMS system is that instead of using a stirrer it uses the pressure from the ink delivery and recycling pumps which, because they pressurise the system, also affect the way the ink is delivered to the print head. The system pressurises the ink to an optimum level, creating a vacuum pressure reservoir so the pigment cannot easily separate from the binder. The system also pressurises the ink in the actual print head to a level that results in a more consistent coverage when printing, explains Whitmore. This also in turn reduces the risk of the print head and dampers drying out and therefore extends the life of both parts.

"WIMS is probably the most major development with direct to product ink jet printing since the printers first hit the market," he says. "This revolutionary system reduces the amount of ink used in head cleaning, extends the life of the print head, dampers and tubing and delivers an improved consistency in print quality - all of which either save or earn money for the user. It has taken three years of development and testing to reach this point but if you ask those already using WIMS "was it worth it?" then the answer will be a resounding yes."

The system can also be retro-fitted to earlier machines, contact YES for more details.

The other area of development at DTG has been with Eco Solvent inks. Although these are not new, their use in this style of printing has been limited, explains Whitmore. "One of the major problems with solvent inks and ink jet printers was that the former did not suit the latter, creating expensive problems," he says.

But DTG and YES claim to have solved that by introducing head-friendly Eco Solvent inks, designed to bring the same lucrative opportunities enjoyed by the direct to textile market to the hard surface market.

The inks work well on most rigid hard surface products even those that normally have difficulty in accepting the ink. In a way the ink fuses to the surface of the product, producing a more durable finish with an increased scratch resistance, says Whitmore. "A few products may need pre-treatment but all in all, the introduction of the new inks is a major breakthrough for this style of printing," he says.

"Although only a few years old the direct to product ink jet printing market has developed well," adds Whitmore, "opening up new opportunities and markets as well as satisfying some that were already there but that could not be fulfilled. DTG and YES have worked hard to further develop the product, not just in the type of market that could be attacked, but also in how the machines delivered profit.

"The introduction of Solvent ink and WIMS satisfy both aims. The former opens up new markets and opportunities giving you the chance of adding a new profit centre to your business whilst the latter simply enables the machine to deliver increased profit by saving on expensive ink."

Tel: 01623 863343

Email: sales@yesltd.co.uk    

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