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Santovac 5  Diffusion Pump Fluid
500cc Bottle

Santovac 5
500 cc Bottle

• Polyphenyl Ether Diffusion Pump Fluid
• Vacuum Diffusion Pump Oil
• Used in some Varian (Agilent) Leak Detectors
• Includes 2017 Vendor Price Increase

Former LDS Part Numbers:

500cc - Santovac 5

Santovac 5 Diffusion Pump Oil


Light Yellow (Essentially Clear Liquid)


Odorless to slight phenolic

Boiling Point

889F @ 760 mm Hg

Pour Point 


Specific Gravity

1.195 - 1.201 @ 25/25C



Vapor Density

15.5 (Air = 1)


Soluble in Acetone & Light Aromatic Solvents;  Insoluble in Water

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Santovac 5 is a five-ring polyphenyl ether fluid, operates efficiently, economically and safely in diffusion pumps to produce ultra-high vacuums in the 10-10 torr range in properly designed systems. Santovac 5's wide liquid range, low vapor pressure, and the unique balance of properties listed below make it an ideal candidate for your vacuum needs.

LOW VAPOR PRESSURE: Extremely low vapor results in low ultimate pressures. Vapor pressure of Santovac 5 at 25°C, (obtained by extrapolation at higher temperature data) is 4x10-10 torr. This means lower ultimate vacuum.

LOW BACKSTREAMING: Backstreaming depends on the vapor pressure of the fluids, the system design, operating conditions and the temperature of the collecting surface. Santovac 5 has inherently low backstreaming characteristics -- as low or lower than any other commercially available fluid.

The result is less contamination in chambers and longer-term operation for those processes that are sensitive to organic matter. This makes polyphenyl ether type fluids like Santovac 5 well suited for electronic component applications.

Contact LDS Vacuum with any questions:
Phone (407)862-4643 via Fax (407)862-8723 or

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