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ECO-705 Silicone Diffusion Pump Oil

ECO-705 Silicone Diffusion Pump Oil

Regular price $475.00 $650.00 Sale

Our products also come in 5 gallon and other large sized packaging, inquire about discount pricing by calling our hotline at 1 (855) 208-2005 or by sending us an email at info@diffusionpumpoilc.com.
  • ECO-705 diffusion pump oil is the perfect replacement for Dow Corning DC-705 diffusion pump oil that offers higher performance with a longer service life. We guarantee you will not find a better replacement for DC-705.

    ECO-705 is a clear, single component, high viscosity pentaphenyl-trimethyl-trisiloxane silicone fluid manufactured specifically for use in diffusion pumps with an ultra-high vacuum range of 10E-10 torr untrapped and 10E-11 torr trapped.

    Compared to ECO-702 and ECO-704, ECO-705 diffusion pump oil offers the highest phenyl content as well as the lowest vapor pressure allowing the most resistance to oxidation and radiation. Therefore, if you're in an application where contamination is a factor, we highly suggest using ECO-705.

    As our top-of-the-line diffusion pump fluid, the ECO-705 is an excellent choice for space-simulation chambers, thin film coating systems, plasma physic research, and in high purity metalizing applications where thermal, radiation and chemical stability as well as quick pump-down is a requirement.

    *Next day shipping is available only when orders are placed before 12PM EST.

    Compare Specifications

    Specifications ECO-705 DC-705 (Dow Corning, Discontinued)
    Chemical Profile Penta Phenyltri-methyltrisiloxane Penta Phenyltri-methyltrisiloxane
    Color Transparent Transparent
    Ultimate Vacuum (untrapped) 10E-9 to 10E-10 torr 10E-9 to 10E-10 torr
    Extrapolated Vapor Pressure 3 x 10E-10 torr 3 x 10E-10 torr
    Specific Gravity at 25°C 1.09 1.09
    Viscosity at 25°C 175 cSt 175 cSt
    Flash Point (open cup) 243°C 243°C
    Boiling Point (at 0.5 torr) 245°C 245°C
    Hazardous Ingredients None None
    Chemical Profile Mixed Phenylmethyl-dimethyl cyclosiloxane Tetramethyltetraphenyl-Trisiloxane Penta phenyltri-methyltrisiloxane
    Color Clear/Light Straw Transparent Transparent
    Ultimate Vacuum (untrapped) 10E-6 torr 10E-7 to 10E-8 torr 10E-9 to 10E-10 torr
    Ultimate Vacuum (trapped) - to 10E-11 torr 10E-11 torr
    Extrapolated Vapor Pressure 1 x 10E-6 torr 2 x 10E-8 torr 3 x 10E-10 torr
    Specific Gravity at 25°C 1.07 1.07 1.09
    Viscosity at 25°C 45 cSt 39 cSt 175 cSt
    Flash Point (open cup) 193°C 221°C 243°C
    Boiling Point (at 0.5 torr) 180°C 215°C 245°C
    Typical Boiler Temperature 220°C 230°C – 240°C 250°C – 260°C
    Surface Tension 30 dynes/cm 37.3 dynes/cm 36.5 dynes/cm
    Heat of Vaporization (kcal/g mole) 21.7/190°C 25.5/200°C 28.2/250°C
    Refractive Index at 25°C / 77°F 1.5550 – 1.5650 1.5500 – 1.5600 1.5765 – 1.5785
    Congealing Point - -35°C / -31°F -14 to -18°C / 6.8 to -0.4°F
    Hazardous Ingredients None None None
    Shelf Life 5 Years 5 Years 5 Years
  • If you have any questions regarding the MSDS-files, feel free to contact us.

    Download US Version: msds-logo ECO-705 Diffusion Pump Oil MSDS (ver. us)
    Download EU Version: msds-logo ECO-705 Diffusion Pump Oil MSDS (ver. eu)
  • ECO-702

    ECO-702 is by far the most affordable type of silicone diffusion pump oil and is considered to be a general-purpose oil recommended for larger volumes of gas and can attain chamber vacuum pressures up to 10E-6 torr. ECO-702 is ideal for general manufacturing that gives off a larger amount of gas. A part from diffusion pumps, ECO-702 can alternatively be used in any vapor ejector pump to attain a maximum vacuum of 10E-5 torr.


    ECO-704 is the most commonly used diffusion pump oil on the market. It is suitable for a wide range of heavy operations and offers a quick pump-down. It is a single-component oil with a pure chemical profile of Tetramethyltetra-phenyltrisiloxane which can produce a ultimate vacuum of 10E-7 torr to 10E-8 torr in a untrapped state and 10E-10 torr to 10E-11 torr in a trapped state. The main reason why so many manufacturers choose ECO-704 is due to its ability to withstand tough and rugged operations while producing an extremely powerful vacuum. Most diffusion pump oils cannot come in the slightest contact with air, but ECO-704 can actually handle air-exposure when operating temperatures are reached.


    ECO-705 is the most advanced diffusion pump oil up to date. Just like ECO-704, it is a single-component oil and is made of high-quality and pure Penta phenyl tri-methyltrisiloxane. ECO-705 is basically an upgraded version of ECO-704 with a ultrahigh vacuum of 10E-9 torr to 10E-10 torr in a untrapped state, and up to 10E-11 torr when trapped. It offers such powerful vacuum and low vapor pressure that most diffusion pumps operating on ECO-705 can withstand radiation and do not need a cold trap or refrigeration because of its ultrahigh and yet smooth applications. Overall, all three types of diffusion pump oils by Enparticles have their own unique profiles and advantages. If you have questions, make sure to read our FAQs or contact us.