With the rapid development in semiconductor manufacturing, aerospace engineering, nuclear physics research, and high-end analytical instruments, the ability to obtain and maintain an ultra-high vacuum environment has become one of the important indicators for measuring a country's technological competitiveness. As the core working medium of ultra-high vacuum systems, the performance of diffusion pump oil directly determines the system's ultimate vacuum degree, return oil rate, and operational stability. The product, 705 (domestic brand 275), launched by Anhui Aiyota Silicone Oil Co., Ltd., demonstrates outstanding applicability under extremely demanding conditions with a saturated vapor pressure as low as ten to the power of negative nine, excellent thermal stability, and antioxidant properties. It provides reliable oil supply for high-end vacuum applications. 
I. Core Physical and Chemical Parameters of the Product 
The product ultra-high vacuum diffusion pump oil 705 is a colorless transparent oily liquid. At 25 degrees Celsius, its kinematic viscosity ranges from 170 to 175 square millimeters per second. Its refractive index is from 1.5765 to 1.5785, and its relative density is from 0.090 to 0.10. The open cup flash point is not lower than 243 degrees Celsius, and the freezing point ranges from -14 degrees Celsius to -18 degrees Celsius. 
The core technical advantage of this product lies in its outstanding vacuum performance indicators. The ultimate vacuum level can reach an extremely high level of less than one times ten to the power of negative nine torr to ten times ten to the power of negative ten torr, and the saturated vapor pressure is lower than three times ten to the power of negative ten torr. This extremely low vapor pressure characteristic ensures that under ultra-high vacuum working conditions, the volatile molecules of the oil itself contribute very little to the system vacuum degree, effectively avoiding the risk of oil vapor contamination of the evacuated container and the surface of the workpiece. At the same time, its flash point higher than 243 degrees Celsius and good thermal stability enable the pump oil to maintain chemical inertness during the heating evaporation and high-speed jetting working processes, resist thermal oxidation degradation, and extend the service life of the oil. 
II. Widespread Application Domains 
The ultra-high vacuum diffusion pump oil 705, with its outstanding vacuum performance and thermal chemical stability, can play a crucial role in several cutting-edge technologies and high-end manufacturing fields, including: 
1. Semiconductor and Integrated Circuit Manufacturing. In the key processes of chip manufacturing such as lithography, etching, ion implantation, and chemical vapor deposition, an ultra-high vacuum environment is the fundamental condition for ensuring the cleanliness of the wafer surface and the performance of the devices. The product ultra-high vacuum diffusion pump oil 705 can provide the ability to achieve ultra-high vacuum for mainstream semiconductor manufacturing equipment. Its extremely low oil return rate effectively reduces the adverse effects of particles and organic pollutants on the yield of chips, and is suitable for the vacuum processes of large-scale integrated circuits, power devices, and MEMS sensors, etc. 
II. High Vacuum Smelting and Special Metal Processing. In the production processes of high-end alloys such as vacuum induction melting, vacuum arc remelting, and electron beam melting, the product ultra-high vacuum diffusion pump oil 705 can maintain a vacuum degree of less than 10 to the power of minus 8 torr in the melting chamber, effectively removing gases and impurities from the molten metal, and improving the purity and performance of special metals such as high-temperature alloys, titanium alloys, and superconducting materials. At the same time, it can also be used in the high vacuum coating field for vacuum evaporation and sputtering deposition processes of functional films such as optical lenses, precision molds, and decorative coatings. 
III. Manufacturing of Electron Tubes and Vacuum Devices. The product's ultra-high vacuum diffusion pump oil 705 is widely used in the exhaust and packaging processes of high-power electron tubes, speed-regulating tubes, magnetron tubes, and traveling wave tubes, which are microwave vacuum electronic devices. In these devices, the ultra-high vacuum degree directly determines the output power, efficiency, and service life of the devices. The excellent oxidation resistance and chemical stability of this product ensure stable vacuum performance during repeated high-temperature baking and exhaust processes. 
IV. Atomic Energy Accelerators and Nuclear Physics Experimental Facilities. The beam pipes and target chambers of particle accelerators need to maintain an ultra-high vacuum of less than 10 to the power of minus 9 torr to reduce the collision and scattering of the beam with residual gas molecules. The product ultra-high vacuum diffusion pump oil 705 can still maintain a low saturated vapor pressure and good stability in a radiation environment, and is suitable for the maintenance of vacuum systems in large scientific facilities such as synchrotron radiation sources, spallation neutron sources, and tokamak nuclear fusion devices. 
V. Electron Microscopes and Surface Analysis Instruments. High-end analytical instruments such as scanning electron microscopes, transmission electron microscopes, Auger electron spectrometers, and X-ray photoelectron spectrometers all have extremely high requirements for vacuum. The product's ultra-high vacuum diffusion pump oil 705 can provide a clean and stable ultra-high vacuum environment for these instruments, ensuring the accuracy of high-resolution imaging and surface element analysis. 
VI. Display and Optoelectronic Device Manufacturing. In the vacuum evaporation processes of OLED panels, quantum dot displays, and thin-film solar cells, product ultra-high vacuum diffusion pump oil 705 can ensure a high vacuum level and low re-oiling rate within the coating chamber, improving the film formation quality of luminescent materials and electrode layers, thereby enhancing the luminous efficiency and lifespan of the devices. 
VII. Space Environment Simulation and Aerospace Testing. The spacecraft thermal vacuum test chamber and space environment simulation equipment need to simulate the extremely high vacuum and extreme temperature conditions in space. The product ultra-high vacuum diffusion pump oil 705 can maintain good fluidity under the low-temperature starting conditions ranging from minus 14 degrees Celsius to minus 18 degrees Celsius, and maintain low volatility and thermal stability under the high-temperature baking degassing conditions, meeting the strict requirements of ground verification tests for aerospace products. 
III. Packaging Specifications and Storage Conditions 
The ultra-high vacuum diffusion pump oil 705 is available in various packaging sizes such as one kilogram plastic bottles, five kilograms, twenty-five kilograms, fifty kilograms plastic drums, and two hundred kilograms iron drums. This enables flexible selection by laboratories of different scales, R&D centers, and production enterprises. The finished product should be stored in a warehouse protected from moisture, humidity, and direct sunlight, with the indoor temperature range allowed to be from minus forty degrees Celsius to fifty degrees Celsius. The finished product is transported and stored as non-hazardous goods. During transportation, it should be avoided from severe impacts and packaging damage, and the container should be kept sealed to prevent external contaminants from entering. If unopened and under storage conditions, the shelf life of this product is three years. 
IV. Quality Assurance and Application Value 
The product ultra-high vacuum diffusion pump oil 705 has established a strict quality control system during the production process. It conducts full-process testing on key indicators such as appearance, viscosity, refractive index, relative density, flash point, freezing point and ultimate vacuum degree to ensure consistency and reliability between batches. Its extremely low saturated vapor pressure and excellent thermal oxidation stability enable it to demonstrate significant technical advantages in high-end vacuum applications. 
With continuous investment by our country in strategic scientific and technological fields such as semiconductors, aerospace, nuclear physics, and new materials, the demand for ultra-high vacuum acquisition and maintenance technologies will continue to expand. The product ultra-high vacuum diffusion pump oil 705, as a representative of domestically produced high-performance vacuum oil products, its stable quality and excellent performance are gradually replacing imported products, providing strong support for the independent guarantee and cost optimization of domestic high-end vacuum equipment, and helping our country's vacuum science and technology industry reach a higher level.