In this paper, the high-gas-barrier properties of a-C:H films are summarized and the possibility of the wider applications of a-C:H films for food and beverage containers is discussed. Coating a-C:H films inside polyethylene terephthalate (PET) bottles dramatically improves the gas barrier property and accordingly, the oxygen transmission rate (OTR) becomes extremely low (∼1/30 of uncoated bottles). In fact, the coating equipment for PET bottles operated by the radio-frequency plasma-enhanced chemical vapor deposition (CVD) method under low pressure has been developed and has already been in practical use. Recently, a unique and cost-effective atmospheric-pressure glow plasma CVD technique was introduced by our group as the substitute for the low-pressure CVD technique. Homogeneous and highly stable plasma was constantly generated under an atmosphere of acetylene gas (C2H2) without using any other dilution gases such as He, Ar and N2. It was found that by using a pulsed power supply operated at a frequency of 35 kHz with a voltage of 24 kV, high gas-barrier a-C:H films were synthesized under atmospheric pressure, which implies that the new power supply would eventually lead to the development of a new atmospheric-pressure glow plasma CVD technique.
|ジャーナル||New Diamond and Frontier Carbon Technology|
|出版ステータス||Published - 2006 7 10|
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