*NEWS*WHY KYOCERA ENTERED INTO INKJET HEAD BIZ ?
*NEWS*WHY KYOCERA ENTERED INTO INKJET HEAD BIZ ?
2008-04-02 at 2:36:23 pm #19758
Why Kyocera Entered Into Inkjet Head Biz?
Kyocera Corp developed an inkjet head for commercial printers and will make it a business in April 2008.
has the largest share (a little less than 50%) of the world market for
the heads for thermal transfer printers, the company said. Also, the
company engages in the businesses of photoreceptors, LED heads and so
forth for electrophotographic printers.
Kyocera will strengthen
the business related to commercial printers by introducing the new
inkjet head. I interviewed Hisamitsu Sakai, the company’s general
manager of the Inkjet Division, and Sumio Arima, the company’s deputy
manager of the Printing Device Sales Department, Corporate Thin Film
Components Group.Why did you enter the business of inkjet heads?We
consider that there is a large potential market for the commercial
inkjet printers that are suited for printing a wide variety of images
in small quantities and can print on demand without using a plate.The
market size for inkjet printing, including printing equipments and
inks, is only about ¥3 trillion (US$30 billion). But, the market for
the printing business as a whole is large. For example, the market size
for general printing, which uses a plate, is reportedly ¥70 trillion
(including equipments and inks).Though printing equipments that use a
plate are not suited for printing a wide variety of images in small
quantities or for on-demand printing, commercial inkjet printers have a
broader range of applications (Fig 1). Also, they will create demand
for those new applications, expanding the print market.For example,
recently, various types of ads and coupons, in addition to the card
holder’s name and the detailed statement, are printed on credit-card
bills. The name and the statement are different from person to person,
but the ads and coupons are the same due to a limited printing cost.If
commercial inkjet printers are used, it is possible to print ads and
coupons that are different from person to person. And it will increase
the value of the ads and, thus, boost the demand for printing.We
already had many business talks. The new print head will be mounted in
a printer developed by Miyakoshi Printing Machinery Co Ltd, who helped
us test the head. Also, we are conducting negotiations with several
The new inkjet head is targeted at the printers
used in those business fields. And we solved the problems of inkjet
heads.What kind of problems did they have?There have been three major
problems in using inkjet printers for commercial printing, slow print
speed, bad image quality and low durability. For example, offset
printing machines, which are often used in commercial printing, have a
printing speed of 150m/min for general use and 1,000m/min for printing
newspapers and others. The speeds of electrophotographic printers are
60-90m/min.In the case of inkjet printers, those with high image
quality, 300-600dpi, have a printing speed of about 60m/min. Some
inkjet printers for commercial use are as fast as 300m/min. But they
are monochrome, and their resolution is as low as 150dpi.However, our
new inkjet head has a printing speed of 75m/min. Its resolution is
600dpi. So, we achieved both high resolution and high speed for
commercial printing. When the inkjet heads are arranged in two rows,
the printing speed can be 150m/min, equivalent to the speed of general
offset printing machines.
How did you solve the problems?
increased the number of ink nozzles and enabled each nozzle to
discharge about 30,000 ink droplets per minute. We increased the width
of the inkjet head to 108mm, one of the widest in the industry,
expanding the area that can be printed at one time (Fig 2). As a
result, each inkjet head has 2,656 nozzles. Also, the ink channels are
designed so that they do not get clogged with ink.
It is a piezo
print head, which discharges inks by expansion and contraction of
piezoelectric elements. In general, it is difficult to increase the
resolution of piezo inkjet printers because a piezoelectric element has
to be set in each nozzle and, to enhance the resolution, it has to be
finely processed.To solve this problem, we decided to use ceramic flat
plates, which are piezoelectric materials. Many electrodes are formed
on a thin and flat ceramic plate, and the plate is set on top of the
tank that stores ink (Fig 3). In other words, several piezoelectric
elements are accumulated on a ceramic flat plate (Fig 4).The ceramic
plate is densely mounted with electrodes, but the plate itself is not
finely processed. Therefore, it is relatively easy to increase the
resolution. We have already obtained a patent for this technique of
using a flat plate.We improved the ceramic material too. We cannot
reveal the details of the material, but the new material is more
responsive and generates more power when a voltage is applied. Our
strength lies in ceramic materials, and we took advantage of it.The
ceramic plate is about 20µm thick, and the amount of displacement is
about 100nm when a voltage is applied. The width of the ink channels
that flow from the ink tank to each nozzle is several dozen
micrometers. The inkjet head has a total of 2,656 piezoelectric
elements on four ceramic flat plates (Fig 5).
You cooperated with Brother Industries Ltd to develop the inkjet head.
we have the know-how in thermal transfer printers and
electrophotographic printers, we had to start the inkjet printer
business from scratch. So we cooperated with Brother Industries, a
pioneer in that field.Brother Industries, whose strength lies in its
inkjet technologies, and Kyocera, who has the advantage of
piezoelectric material technologies, complemented each other in
developing the basic technology for the new inkjet head. Not only our
company but also Brother Industries can use the newly developed
technology.The development period is five years, from 2002 to 2007.
After that, we conducted reliability tests for the inkjet head. We had
verification experiments, for several months, where printed paper could
often be as long as 100km per day and confirmed that the image quality
does not deteriorate.
What is your future plan?
further improve the resolution and print speed. We have the advantage
of dealing with ceramic materials. The resolution of 600dpi is still
low compared with conventional printing technologies. We look to
enhance the resolution to 1,200dpi.If the arrangement of the inkjet
heads is changed, it is possible to have 1,200dpi at this point.
However, it would require an accuracy of a few micrometers to set the
inkjet heads to the device. If we can achieve 1,200dpi by improving the
head, we do not have to deal with this problem.As for the print speed,
we would not like to define a specific goal at this moment. There are
some technological constraints on piezo inkjet printers. So we have to
find those limitations first.