The Story Behind LED-UV Printing System's Development

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RYOBI was the first to successfully develop an energy-saving, environment-friendly LED-UV printing system, which was launched onto the market in 2008 and offers numerous advantages over a conventional UV curing system. We talked with the RYOBI staff about the system's development, its future marketability, and its environmental contribution in a roundtable discussion moderated by Mr. Atsushi Okuyama, director of the Society for the study ecology printings.

Moderator: Atsushi Okuyama

Mr. Okuyama served in the Paper and Printing Industry Section of Japan's former Ministry of International Trade and Industry. After leaving the ministry, he served as a solutions specialist in management positions for software developers and other companies. Mr. Okayama established Com-Design Co., Ltd. in 2003, providing various services related to IT and communications design. He now operates the Society for the study ecology printings, which conducts research on environment-friendly printing, and he is a member of the Eco Mark Printed Matter / Paper Products Standards Revision WG Committee.

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Hideki Ikeda

Assistant Manager

Engineering & Development Section

Engineering Department

Graphic Systems Division

Nobuyoshi Shibata

Manager

Planning &
Development Section

Sales Department

Graphic Systems Division

Hiroyuki Kuroki

General Manager

Engineering Department

Graphic Systems Division

Katsushi Hirokawa

Deputy General Manager

Engineering Department

Graphic Systems Division

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Okuyama:

What was the reaction to the announcement of the LED-UV printing system at Drupa 2008?

Kuroki:

There was a tremendous response. Throngs of visitors were attracted to the RYOBI booth, not only from printing companies, but also from advanced technology research organizations and other groups. While I believe it was already anticipated that someone would be announcing this kind of technology, there was a great deal of excitement when it was actually exhibited and the dry printed sheets came out.

Shibata:

After Drupa 2004, one development theme proposed for Drupa 20080 was "a drying system that would reduce electricity consumption by half." In preparation for the coming age of environment-friendly printing, this was considered a theme that RYOBI definitely had to tackle.

Kuroki:

Mr. Ikeda here had the opportunity to look at the LED-UV system exhibited at 2005 Electrotest Japan, and reported back that he thought it would someday replace the lamp type system we were currently using. That was a key factor in our decision.

Okuyama:

I've heard that development of the LED-UV printing system involved collaboration with Panasonic Electric Works and Toyo Ink. As RYOBI was responsible for developing the printing equipment parts of the system, what kinds of difficulties or innovations were involved in making the printing equipment compatible with this new system?

Hirokawa:

Achieving good LED irradiation efficiency requires moving the LED source as close as possible to the paper. This creates the problem of possible contact with the paper. In this system the LED source is installed above the impression cylinder, where paper transport is most stable. A sheet paper offset printing press uses various paper sizes, both large and small. To maximize the LED-UV printing system's electrical efficiency, we had many discussions with Panasonic Electric Works on how to control the electrical power output to suit paper width.

Okuyama:

Our Society for the study of ecology printings presents printing industry trends relating to environmental issues, and reports various research results. What kinds of advantages, including from an environmental viewpoint, does this LED-UV printing system offer printing companies?

Shibata:

Well, while fast drying using UV ink is very attractive from the viewpoint of preventing ink smears on the back of printed sheets and reducing the use of spray powder, previous UV printing systems presented various hurdles, such as high electricity consumption and the large size of the peripheral equipment. For customers who were hesitating to introduce UV printing for those reasons, this LED-UV printing system represents a major breakthrough.

Ikeda:

The biggest advantage is, of course, lower power consumption. The system also reduces CO2 emissions, an environmental issue of concern. After stopping a press, previous UV printing systems always required time for the lamp to warm up before printing could be resumed. With the LED-UV printing system there's never any waiting time. Printing can be resumed just like when you use oil based ink.

Shibata:

And the LED light source has a life of 15,000 hours, about 15 times longer than a lamp type system, so replacement is less frequent.

Okuyama:

One area that our Society of the study of ecology printings focuses on is the reduction of VOCs (volatile organic compounds). The printing industry is said to account for 13% of all the VOCs generated. Does the LED-UV printing system also reduce VOCs?

Kuroki:

The ink developed for the LED-UV printing system is a non-VOC type, so the system is effective at reducing VOCs. Ink manufacturers other than TOYO Ink have also begun to offer non-VOC ink, so in the future the selection available is expected to increase.

Okuyama:

While various conventional inks are non-VOC and environment-friendly soy inks have also been developed, UV ink has the distinct advantage of speed thanks to UV curing. Shorter lead times through instant drying and environment-friendly printing are definitely major advantages.

Okuyama:

Changing the subject, could you tell me what kind of customers RYOBI is targeting with the LED-UV printing system?

Shibata:

Up until now we've been targeting printing companies that are aggressively promoting environment-friendly printing. Such companies actively publicize that they're involved in environmental activities through collaboration with various manufacturers. We believe that printing companies who are getting their customers concerned about environment-friendly printing as part of their business strategy are likely to be very interested in the LED-UV printing system.

Okuyama:

RYOBI exhibited an A-3 plus size press equipped with LED-UV printing system at Drupa 2008, and development of a system for B2-size presses has also been announced. Tell us about this development and what future you see for the LED-UV printing system.

Hirokawa:

The basic technical elements of the LED-UV printing system have now been established, including the drying performance, development of compatible ink, and printing know-how. Based on these technical elements, RYOBI will now gradually develop various press variations. Regarding printing on film and coating, which may be our next development themes, we are already collaborating with ink manufacturers and may come up with some solutions addressing those issues in the very near future.

Kuroki:

System integration with an offset press makes various control methods and applications possible. It's also possible that the LED unit itself can be made more compact, and various combinations may be tailored to match specific applications, such as installation of multiple LED-UV printing systems on a single press. We plan to work together with our customers to come up with more applications.

Okuyama:

Working on development together with customers is very important. And, if you can take that a step further, I'd hope that you'll also look at things from the viewpoint of the customers' customers - the people ordering the printing work. I think that accurately discerning their real needs, whether immediate and pressing or deep level, is key to proposing the best solutions. I look forward to the further development of the LED-UV printing system and RYOBI's other environmental activities. Thank you for participating in today's valuable discussion.