Selection Guide for Dimethyl Silicone Oil Viscosity in Fluid Lamps for Permanent Display

Types of Fluid Lamps and Silicone Oil Selection

1. Traditional Lava Lamps: They use a mixture of mineral oil and wax, and generally do not use dimethyl silicone oil.
2. Silicone Fluid Lamps: They specially use dimethyl silicone oil as the main liquid and are suitable for permanent display. Thanks to its high chemical stability, low volatility, high temperature resistance (-50℃~+200℃) and almost unchanged viscosity with temperature variations.

Recommended Optimal Viscosity

Reasons for Choosing This Viscosity Range

1. Stability: Silicone oil within the range of 50–500 cSt maintains an ideal balance of fluidity and stability at room temperature, ensuring the fluid lamp effect lasts for a long time without flowing too fast to cause visual fatigue.
2. Anti-aging Property: Dimethyl silicone oil in this viscosity range has extremely low volatility (≤1.5%), so it hardly diminishes or deteriorates during long-term display, guaranteeing a consistent permanent display effect.
3. Temperature Adaptability: Silicone oil has a very small viscosity-temperature coefficient. Temperature changes have minimal impact on its viscosity, allowing it to maintain stable flow characteristics across different ambient temperatures.

Practical Recommendations

• Avoid low-viscosity silicone oil (< 50 cSt): It has overly strong fluidity, making it difficult to form a stable fluid shape. Moreover, slight volatilization during long-term display may affect the effect.
• Avoid high-viscosity silicone oil (> 1000 cSt): It is excessively thick and flows extremely slowly or even nearly stops, losing the dynamic beauty of the fluid lamp.
• Brand Selection: It is recommended to use Type 201 dimethyl silicone oil (e.g., 201-100, 201-350, 201-500). As an industry-standard model, it offers stable performance at a moderate price.

Summary

For fluid lamps designed for permanent display, dimethyl silicone oil with a viscosity of 350–500 cSt is recommended. It achieves the optimal balance among fluidity, stability and durability, ensuring the fluid lamp retains its attractive dynamic effect during long-term display. If you need to adjust the flow speed, you can choose a viscosity within the range of 50–1000 cSt: the higher the viscosity, the slower the flow; the lower the viscosity, the faster the flow.