Inkjet News

Thin-film piezo offers Highest Distortion

According to Seiko Epson Corporation , they have developed a thin-film piezo element that boasts the world’s highest degree of distortion. Epson announced volume production of next-generation Micro Piezo print heads that feature these elements as actuators will be launched in April 2007.

Current Micro Piezo Print Head Overview

The Micro Piezo print head is an inkjet print head which utilizes Epson’s original Micro Piezo technology. This technology uses electrical signals to change the shape of piezo elements and then fires ink droplets according to the physical force generated by the change in shape of these elements. Epson’s Stylus Photo and Stylus Pro inkjet printers, which utilize Micro Piezo print head technology, are photo-quality printers that have consistently played leading roles in the Japanese inkjet printer market and earned high approval and trust from customers.

Newest Developments

Epson is currently focusing its development efforts on creating a next-generation Micro Piezo print head to support expansion of the inkjet field beyond consumer printers and to strengthen its applications for business and industry. Through these efforts, Epson has achieved the following:

a) Created a piezo element with the world’s highest degree of distortion through film thickness reduction and materials development.

b)Raised density levels by developing and utilizing innovative thin-film processing techniques.

c) Designed a high-density ink reservoir through independent MEMS technology development.

Benefits
 
As a result, Epson has managed to develop a nozzle with a density of 360 dpi—the world’s highest for an inkjet print head using piezoelectric technology—while at the same time maintaining the advantages of conventional Micro Piezo print heads.

Epson has also managed to establish a completely independent manufacturing process by producing the piezoelectric materials in-house.

The installation of these next-generation Micro Piezo print heads in printers and other devices will make it possible to design speedier and more compact inkjet equipment than ever before.

Current Technology

Special characteristics of Epson’s original Micro Piezo print head

This print head fulfills all the requirements for an inkjet print head—superior ink ejection performance, compatibility with a wide variety of inks, and durability. The print head also makes it possible to control not only water-based pigment ink with superior water and light resistance, but also a wide variety of ink types in miniscule quantities, and fire them with high precision.

1. Ink ejection performance* Meniscus control, which limits vibration on the surface of the liquid in the nozzle, makes it possible to achieve improved gradation and faster print speeds in addition to the following advantages:

a)Perfectly spherical dots

b) High precision impact point control

c) Higher drive frequencies

d)Variable-sized ink droplets (MSDT: multi-sized dot technology)

2. Ink compatibility* Epson’s original pigment ink achieves high levels of color reproduction and durability.* Industrial applications such as solvent ink, color filters, and UV ink are currently under development.

3. Durability* Because it utilizes a permanent print head, the technology is applicable to a wide range of uses ranging from consumer printers to industrial manufacturing equipment.Features of the next-generation Micro Piezo print headBy independently developing a thin-film piezo element which has the world’s highest degree of distortion and using it as an actuator, Epson has succeeded in taking full advantage of the features of conventional Micro Piezo print heads while at the same time doubling nozzle density. A conventional Micro Piezo print head’s nozzle density is 180 dpi (maximum) whereas a next-generation Micro Piezo print head’s is 360 dpi.

Structure of the next-generation Micro Piezo print head

1. Cross-section diagram of next-generation Micro Piezo print head

2. Enlarged photo of nozzle plate

3. Thin-Film Piezo distortion

CAV: cavity, ink reservoir

Note: The degree of distortion has been expanded vertically in the diagram to make it easier
to visualize.

Actuator

A component which converts energy input into physical force.

Piezo element/Piezoelectric material

An element which expands or contracts microscopically when an electrical voltage is applied. It is often used as an actuator or sensor because of its unique characteristics.

MEMS (Micro Electro Mechanical Systems)

Devices for which semiconductor processes are used to integrate mechanical elements, actuators, electronic components, and other functions into circuit modules.

Solvent ink

A type of ink that has high weather resistance and is often used for printing materials such as outdoor signage.

UV ink

A type of ink that hardens when it reacts with ultraviolet light. It has high weather resistance and is often used for printing materials such as outdoor signage.