Coating technology employing atmospheric pressure glow plasma processing
As a generating method for a thin optical film that is coated on the surface of a lens or a prism to control reflection and transmission of light, and for a highly functional film using a phosphor, a vacuum deposition, sputtering and ion plating are used generally. In Konica Minolta, its own vacuum deposition technology is put on practical use, and at the same time, we are investigating the development of the atmospheric pressure glow plasma processing that can coat a large image area uniformly without using vacuum. What has arrived at the level of practical use first in the world is the system to generate a thin film at high speed, by using nitrogen as discharging gas, and by causing high density plasma glow discharge under the air pressure, eliminating use of a vacuum. According to a common opinion, this system is an extremely difficult technology which had been considered impossible because the thin film absorbs the gas, and therefore, high quality cannot be obtained.
Special features of atmospheric pressure glow plasma processing
Because of low temperature deposition, the deposition can be carried out also on a resin base, and this system can be developed to various products. This system can easily be interlocked with another process such as coating, in addition to possibility of continuous deposition, and it can cope with the trend to multiple layers and higher functions.
Examples of practical use of atmospheric pressure glow plasma processing
There have been developed various production techniques coping with various uses such as antireflection coating as optical products, water-repelling and oil-repelling films that control adhesion of contamination, transparent conductive film necessary for flat panel displays and antistatic coatings.
Coating on a material that is not resistant to heat and coating on roll-shaped film have become possible, thereby, high speed production, flexible members and large areas have been made possible.
A nano-thin-film lamination forming technology is drawing public attention as a technology indispensable for higher functions of members in a flat panel display field such as liquid crystal, organic EL and electronic paper, as well as in optical fields.