The Core Medium for High-Vacuum Environments: Diffusion Pump Oil

In industrial production and scientific research that require high-vacuum environments, diffusion pumps are one of the key devices for achieving high vacuum. As the core working medium of diffusion pumps, the performance of diffusion pump oil directly determines the ultimate vacuum level, pumping efficiency, and operational stability of the vacuum system. An ideal diffusion pump oil must have an extremely low saturated vapor pressure, excellent thermal stability, and strong oxidation resistance. This ensures that it does not easily decompose under high-temperature jet conditions and can rapidly condense after cooling, thereby continuously and efficiently removing gas molecules.

IOTA 704: Designed for High-Vacuum Applications

IOTA 704 is a diffusion pump oil specifically designed for high-vacuum diffusion pumps. It is a colorless, transparent oily liquid that, thanks to its outstanding physical and chemical properties, can meet the vacuum demands of a variety of harsh operating conditions.

• Extremely Low Saturated Vapor Pressure: The saturated vapor pressure of IOTA 704 is below 2×10⁻⁸ Pa, enabling diffusion pumps to achieve an ultimate vacuum of 10⁻⁷ to 10⁻⁸ Pa and providing a clean vacuum environment for precision processes.
• Excellent Thermal Stability: In processes that require sustained high-temperature heating—such as high-vacuum smelting and vacuum coating—thermal stability of the pump oil is critical. IOTA 704 offers excellent thermal stability and oxidation resistance, maintaining stable performance under prolonged high-temperature operation, reducing decomposition and coking, and extending oil change intervals.
• Reliable Physical Properties: It has an open-cup flash point of ≥210°C and a pour point of -35°C, allowing stable operation across a wide temperature range. Its viscosity at 25°C is 38±3 cSt, ensuring good fluidity and sealing performance.

Wide Range of Applications

Thanks to its stable performance, IOTA 704 is widely used across multiple industries and equipment that require high-vacuum environments.

• Vacuum Metallurgy & Materials Preparation: Used in high-vacuum smelting, vacuum sintering, vacuum heat treatment, and other processes to ensure that materials are melted and processed in a pure environment.
• Optical & Electronic Coating: Used as a working medium in vacuum coating machines for producing optical lenses, decorative coatings, tool hardening films, and more, ensuring coating purity and adhesion.
• Electronics & Display Device Manufacturing: Used in the evacuation and encapsulation processes of electron tubes, light bulbs, displays, and other devices, creating the necessary vacuum environment.
• Scientific Research Equipment: Suitable for high-end research instruments such as atomic energy accelerators, electron microscopes, and mass spectrometers, providing foundational support for cutting-edge scientific research.

Technical Specifications

表格

Parameter	Value
Appearance	Colorless or transparent liquid
Viscosity (25°C)	38±3 cSt
Relative Density (25°C)	1.06~1.07
Refractive Index (25°C)	1.5500~1.5600
Flash Point (Open Cup)	≥210°C
Pour Point	-35°C
Ultimate Vacuum	<10⁻⁷~10⁻⁸ Pa
Saturated Vapor Pressure (25°C)	<2×10⁻⁸ Pa

About IOTA

As a "full-chain silicone solutions provider," Anhui IOTA Silicone Oil Co., Ltd. is committed to providing customers with full-process technical services, from selection consulting to application support. IOTA 704 is one of our key products for high-vacuum applications. If you are looking for a stable working medium for your diffusion pump, IOTA 704 is a choice worth considering. For detailed Technical Data Sheets (TDS), Safety Data Sheets (SDS), or application consulting, please visit our website or contact our technical team.

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FAQ

What ultimate vacuum can IOTA 704 achieve?
IOTA 704 can help diffusion pumps achieve an ultimate vacuum of 10⁻⁷ to 10⁻⁸ Pa, with its own saturated vapor pressure below 2×10⁻⁸ Pa. Which industries is IOTA 704 suitable for?
It is mainly used in high-vacuum smelting, electron tube manufacturing, light bulb production, vacuum coating, atomic energy accelerators, electron microscopes, and display manufacturing. What are the flash point and pour point of this pump oil?
IOTA 704 has an open-cup flash point of ≥210°C and a pour point of -35°C, offering a wide operating temperature range. How is the thermal stability of IOTA 704?
It has excellent thermal stability and oxidation resistance, making it suitable for long-term use in high-vacuum equipment that requires sustained high-temperature heating. What packaging sizes are available for IOTA 704?
It is available in 1 kg plastic bottles, as well as 5 kg, 25 kg, 50 kg plastic drums, and 200 kg iron drums. Is IOTA 704 a hazardous material? What are the transport and storage requirements?
IOTA 704 is transported and stored as a non-hazardous material. It should be stored in a moisture-proof warehouse away from direct sunlight, with a storage temperature range of -40°C to 50°C. What is the shelf life of IOTA 704?
Under the specified storage conditions, the shelf life is 3 years. What is the viscosity of IOTA 704?
At 25°C, its kinematic viscosity is 38±3 cSt. How can I obtain technical documentation for IOTA 704?
You can visit the Anhui IOTA Silicone Oil Co., Ltd. website or contact our technical team to obtain the complete Technical Data Sheet (TDS) and Safety Data Sheet (SDS). Can IOTA 704 be used in my diffusion pump?
IOTA 704 is a general-purpose high-vacuum diffusion pump oil suitable for most diffusion pumps requiring a vacuum level in the 10⁻⁷ Pa range. For specific compatibility, we recommend consulting our technical team based on your equipment model and operating conditions.
Silicone Diffusion Pump Oil IOTA 704 （Replacement for DC704）-IOTA