Insulated Glass Desiccant
Application Background
Insulated glass (IG) consists of two or more glass panes separated by spacers, forming a sealed air cavity in between. Any residual moisture in the air cavity causes condensation and fogging on the inner glass surface, seriously degrading thermal insulation performance and service life.
Conventional IG units use aluminum spacers filled with granular molecular sieve desiccant, whereas newer warm-edge technology uses composite spacer tapes (butyl tapes containing molecular sieve activated powder), in which the activated powder acts as an amorphous desiccant embedded directly in the tape material.
Role of Molecular Sieve Activated Powder in Insulated Glass
|
Function |
Description |
|
Air-Cavity Dehumidification |
Adsorbs residual moisture in the sealed air cavity, keeping the dew point below -40 °C |
|
Anti-Condensation / Anti-Fogging |
Completely eliminates condensation on the inner glass surface |
|
Extended Service Life |
Maintains a dry environment over time, preventing spacer corrosion and sealant aging |
|
Improved Thermal Insulation |
Dry air has a much lower thermal conductivity than moist air, providing better insulation |
Technical Advantages
|
Comparison |
Activated-Powder Spacer Tape |
Conventional Aluminum Spacer + Granular Sieve |
|
Desiccant Distribution |
Evenly dispersed within the tape |
Concentrated inside the spacer |
|
Sealing Performance |
Integrated tape seal, no joints |
Multiple seals, joint risk |
|
Thermal Insulation |
Warm-edge technology, reduces edge thermal bridging |
Aluminum spacer has high thermal conductivity |
|
Production Efficiency |
Automated continuous production |
Many process steps, lower efficiency |
|
Moisture Adsorption |
Continuous adsorption, fast |
Requires gas diffusion into the spacer |