(October 27, 2026) The new generation of vacuum diffuser oils for the fields of coating, semiconductors, vacuum metallurgy, and research equipment have passed batch stability tests. With their ultra-low saturated vapor pressure, low oil return rate, and excellent thermal oxidation stability, these products further enhance China’s ability to supply high-vacuum materials domestically, thereby promoting the self-reliance of the high-end vacuum industry chain.

Vacuum diffuser oils are the essential working medium in oil diffusers; they are often referred to as the “blood” of high-vacuum systems. Diffusers use the oil to generate supersonic airflow through heating and vaporization, thereby removing gases. After cooling, the oil returns to the system for continuous operation. The performance of the oil directly determines the maximum vacuum level of the system, the cleanliness of the chamber, and the stability of continuous production processes. In applications such as optical coating, electronic component manufacturing, vacuum metallurgy, material research, and aerospace simulation chambers, if the oil has a high oil return rate or decomposes easily at high temperatures, it can easily cause contamination of the workpieces, reduced yield, and frequent maintenance needs. High-end applications require strict standards regarding oil purity, distillation uniformity, and resistance to aging.

It is understood that the newly developed vacuum diffuser oils undergo advanced molecular distillation processes to control the distillation range, effectively reducing evaporation and backflow. The oil does not easily decompose or form soot under long-term high-temperature conditions, and its oil change interval is significantly longer compared to ordinary mineral-based diffuser oils. These oils can be used in both conventional metal and glass diffusers, as well as in precision coating and electron beam evaporation processes that require high cleanliness levels. The products come in two types: mineral-based and phenylsilicone-based oils, and they can meet the requirements of various levels of high-vacuum environments, from 10⁻³ Pa to 10⁻⁷ Pa, while also meeting the needs of general industrial applications and ultra-high-vacuum research facilities.

Industry experts say that with the expansion of domestic photovoltaic coating, display panel, semiconductor, and precision optics industries, along with the continuous development of high-end vacuum testing platforms in universities and research institutions, demand for high-purity diffuser oils is increasing steadily. In the past, high-end phenyl-based diffuser oils relied heavily on foreign brands, with long delivery times and high purchase costs. In recent years, domestic oil manufacturers have made significant efforts to improve purification processes, optimize formulations, and ensure batch consistency. The performance of domestic diffuser oils has gradually surpassed imported counterparts, and they are now being used on a larger scale in smaller batches, thereby enhancing supply chain resilience.

In terms of industry trends, market demand is shifting from simply pursuing extreme vacuum levels to more comprehensive solutions that emphasize low pollution, long lifespan, low maintenance costs, and stable mass production. Downstream customers also place greater emphasis on technical support related to oils, including guidance on oil selection, oil change procedures, and troubleshooting of vacuum system contamination. Many vacuum equipment manufacturers and coating companies have begun testing domestic diffuser oils, thereby establishing a stable verification system.

It is predicted that with continued advancements in silicone and specialty lubricants, domestic vacuum diffuser oils will further improve in terms of ultra-high cleanliness and low gas emission. They will become increasingly important in high-stakes applications such as semiconductors and aerospace vacuum simulations, providing crucial materials for the domestic high-vacuum equipment industry.