User interview – Professor Sanada and Visiting Professor Nagata, Toyama Prefectural University

Some of you may express an involuntary reaction to words such as “heat dissipating material”, “cellulose nanofiber”, and “self-healing”. I have interviewed two researchers who are studying such topical materials. Both of them have experienced working at a manufacturer and know the situation of both companies and universities. I heard their interesting story.

1. First meeting with THINKY MIXER

You are using THINKY MIXER AR-250* and ARE-310 in your laboratory. How did you learn about our products?

Professor Sanada: I had just started working for the university when I happened to see unfamiliar equipment at the Industrial Technology Center in Toyama Prefecture. It was introduced to me as a filler dispersing device. In the filler system, cleaning is difficult and mixing becomes hard with an increase in viscosity if a blade is used. This equipment has solved all of these problems.

Professor Nagata: The Japanese naming “Awatori Rentaro” of THINKY MIXER is impressive (laugh). “Awatori” is a verb meaning removal of bubbles in Japanese. “Rentaro” is the combination of “Ren” meaning mixing in Japanese and “Taro” which is one of the most popular boys’ names in Japan.
I have been conducting research on filler composites (composite materials). I have worked together with Professor Koichi Ochi of Kansai University for a long time. THINKY MIXER was used in Professor Ochi’s laboratory. At that time, I was researching epoxy-based composites with a major company. THINKY MIXER was also used in their laboratory. I also saw THINKY MIXER at many exhibitions.

2. What kind of application is THINKY MIXER used for in current research?

Professor Sanada: It is used for mixing of ceramics particles into epoxy resin. One of the current research subjects is to convert resin with low thermal conductivity into a composite with high thermal conductivity by adding ceramics particles (with high thermal conductivity).

Professor Nagata: Thermally conductive composites are now one of the topical materials.

3. What are they mainly used for?

Professor Sanada: They are used as heat dissipation materials for electronic equipment. They are used in various parts that do not let electricity pass but allow heat to escape, such as casings, the surroundings of a semiconductor device, and boards.

Professor Nagata: Today, in the field of automobiles, EVs and HEVs require the ability to control large current between a lithium battery and a motor. Therefore, heat control and heat management around a semiconductor device constitute very important technology. Now, “heat dissipation” is in its third boom. The first boom was around 1990.

Professor Sanada: That’s right.

Professor Nagata: When the field of electronics started to grow rapidly in Japan, the field of “heat dissipation” was born to prevent thermal runaway of semiconductor devices, which gave rise to the first boom. After that, the second boom occurred when semiconductors began to be processed into thin wires or multilayers. Now, the third boom corresponds to the technology of controlling the high current in automobiles. Because of the changes in the properties of semiconductors resulting in the use of large currents, more heat is being generated than ever before. At present, in the third boom, researchers are working exceedingly hard in this field.

4. I see. The problem of heat is becoming increasingly important. By the way, you are conducting research on cellulose nanofibers, aren’t you?

Professor Nagata: Yes, we are. Usually, cellulose is dominated by water. In fact, its water content is 80% to 90% and the fiber content is only around 10%. The group at Toyama Prefectural University has established the technology for making cellulose that has a water content of only 3% and is dispersed almost in the solid state.

The experimental stage is already complete and now the stage of collaborative research with various private companies is being started. Chemical manufacturers and several other companies aiming for practical products are willing to participate. Cellulose nanofiber (CNF) has been one of the materials of major national concern for the past 10 years or so, like the carbon fiber first produced by Toray Industries, Inc. I hope the applicability of CNF will also grow and expand through the all-Japanese combination of various excellent skills and technologies developed in Japan.

5. I am looking forward to seeing such development. What are other research subjects?

Professor Sanada: I am studying polymer-based composites with self-healing properties. Epoxy resin is mixed with microcapsules containing a repair agent that adds self-healing properties. Microcapsules will crack if the mixing speed is too high. Therefore, we installed THINKY MIXER ARE-310, whose rotation speed can be controlled.

Professor Nagata: The current research topics are summarized as follows.
(1) Fabrication of composites of nanomaterials and polymers including cellulose.
(2) Self-healing technology (worked on by Professor Sanada).
(3) Heat dissipation material, which is currently attracting much attention.

These three constitute the main subjects. These alone are drawing attention in various fields and many people come all the way to Toyama Prefecture to engage in joint research. Actually, Toyama is really convenient for visitors from Tokyo. I also go to Tokyo almost every week (laugh).

6. Afterword

Currently, Professors Sanada and Nagata are also interested in THINKY MIXER (Vacuum Type) and Nano Premixer PR-1. I must continue to keep an eye on their research in the future. Professor Sanada became a full professor in April and is expected to be more and more active in the research. The two have known each other since they worked together in manufacturing companies. I could feel their friendship during the interview. I thank them for the interesting talk today.

Profile of Professor Kazuaki Sanada

1994	Graduated from Department of Materials Processing, School of Engineering, Tohoku University
1996	Completed Master’s Course, Department of Materials Processing, Graduate School of Engineering, Tohoku University
1999	Completed Doctorate Course, Department of Materials Processing, Graduate School of Engineering, Tohoku University (Doctor of Engineering)
1999	Hitachi Research Laboratory, Hitachi, Ltd.
2003	Lecturer, Faculty of Engineering, Toyama Prefectural University
2009	Associate Professor, Faculty of Engineering, Toyama Prefectural University
2017	Professor, Faculty of Engineering, Toyama Prefectural University

Awards:

March 1994	Young Student Award, Japan Institute of Metals and Materials & Iron and Steel Institute of Japan
July 1995	ICMC Student Travel Assistance Award
April 2010	The Best Presentation Award, Hokuriku and Shin-Etsu Branch, Japan Society of Mechanical Engineers

Profile of Visiting Professor Kazuya Nagata

1979	Graduated from Department of Industrial Chemistry, Faculty of Engineering, Kobe University; Master’s Course, Department of Industrial Chemistry, Graduate School of Engineering, Kobe University; Doctorate Course, Graduate School of Natural Sciences, Kobe University (Doctor of Science).
1981	Kawasaki Resin Research Institute, Showa Denko K.K.
1990	Industrial Technology Center of Okayama Prefecture
2008	Special-Class Highly Skilled Professional, Resin Research Institute, Asahi Kasei Chemicals Corporation

Currently Visiting Professor at Department of Mechanical Systems Engineering, Faculty of Engineering, Toyama Prefectural University (Invited Researcher, MEXT) and Specially Appointed Professor, Institute for Biomedical Sciences, Faculty of Medicine, Shinshu University
He has been consistently engaged in the research on filler filled plastic and rubber composite materials, polymer alloys, adhesion of different materials, and medical polymer materials.

Awards:
Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology
Award of Adhesion Society of Japan
Excellent Paper Award of Adhesion Society of Japan
Excellent Paper Award of Society of Rubber Science and Technology, Japan
Technology Development Award, Japan Institute of Metals and Materials, and six others