Sunoit provide a series of silicone oil used as an alternative to  DC702, DC704, DC705 and many others. They are designed for all types of diffusion pumps and for a very wide vacuum pressure range. The vapor pressure and backflow are so low that the use of cold traps is not required for most vacuum applications. Ultra-high vacuum down to the 10-10 mbar range can be achieved without a cold trap and up to the 10-11 mbar range with a cold trap. It is a significant improvement over all mineral diffusion pump oils .The reconditioning of silicone oil after contact with air at high temperatures is significantly faster than with mineral oils. Even at high oil temperatures, the rate of oxidation and hydrolysis is low if air penetrates.

SNY-704 is chemically named as tetraphenyltetramethyltrisiloxane .

SNY-705 silicone oil is chemically named as pentaphenyltrimethyltrisiloxane.

Due to the highest phenyl content of all diffusion pump oils, they have the best temperature stability. The one-component silicone oil reaches the maximum absorbency in a much shorter time than a multi-component silicone oil or a mineral oil. Diffusion pumps with silicone oil can work up to 20 to 300 percent higher fore-vacuum pressures than when using mineral oils. At medium vacuum pressures, the heating power can be increased by 20-30% to improve suction power.

The chemical structure of the silicone oil results in a high resistance to oxidation and leads to low water absorption at operating temperature. The oil does not react with metals, elastomers or with gases that are common in vacuum. It is especially suitable for pumping out large amounts of oxygen. The chemical stability ensures a long service life for the oil even under difficult conditions. Due to the low vapor pressure and the low backflow of silicone oils, the chamber walls are almost oil-free and can easily be cleaned of process contamination. Silicone oils are chemically and thermally stable even under difficult operating conditions; this allows longer oil change intervals. Significantly higher productivity results in lower operating costs.

Features:

• Extremely wide range of uses
• Chemically inert, highest temperature stability
• Increased suction power of up to 30% compared to mineral oil
• Lowest ultimate pressures
• Shortest conditioning times after an oil change and air ingress
• Longer service life, longer maintenance intervals
• Allows higher pressures in the fore-vacuum
• Lowest oil backflow and therefore lowest contamination of the process chamber