Gel-Pak products are made from a highly cross-linked proprietary polymer material referred to as "Gel". The material immobilizes a device on contact based on surface tension. The degree of holding force is intrinsic to the tackiness of the Gel material, which is referred to as Retention Level. The Gel material is strong in both the shear and vertical directions, but weak in the peel direction, which allows the device to be easily unloaded from the Gel surface.
The Gel material is reusable and has a minimum shelf life of 2 years, making it possible to store devices for extended periods of time. Gel is an extremely durable and versatile material that maintains its properties between -40°C to 220°C.
Over the years, Gel-Pak has refined its Gel chemistry to provide a wide range of retention (tack) levels from an extremely low tack Gel for holding small polished optics to a high tack Gel for holding large ceramic substrates. The standard retention levels available are: XT, XL, X0, X4, X5, X6, X8.
Retention Level Comparison Chart
The optimum tack level for individual devices is dependent on the material type, surface roughness, size, thickness and weight. While there is no exact formula to determine the recommended retention level for a device, the general guidelines are low tack level (XL, X0) for polished surfaces, medium tack level (X4, X5) for etched surfaces, and high tack level (X8) for rough surfaces such as ceramic. The XT retention level is an ultra low tack for special applications.
Standard and Process B Gel
Gel-Pak manufactures two grades of Gel material; a standard grade and a highly purified version (Process B) which is recommended for highly sensitive devices. The Vacuum Release™ (VR) product line is built using Process B Gel. Process B is also available as a special option for the Gel-Box,Gel-Tray®, Gel-Slide, and Gel-Film® products, WF Film, PF Film & DGL Film.
ISO 9001:2008 Cleanroom
Gel-Pak Gel Technology