Copper Ion-Exchanged Zeolite Compact for Vacuum Insulators

The patent employs a porous silicate material (zeolite) as the gas adsorbent. The porous structure provides extensive surface area for gas adsorption while maintaining low thermal conductivity, as the pores trap air and reduce heat transfer pathways. This resolves the contradiction by achieving high gas adsorption capacity through the porous structure without the high solid heat conductivity associated with metallic adsorbents like Ba-Li alloy.

The patent creates a composite material by combining copper ion-exchanged ZSM-5 type zeolite particles with an inorganic binding material. This composite structure maintains the excellent gas adsorption properties of the zeolite while the binding material aggregates the particles into a cohesive form that prevents dispersion during handling and installation, thus improving ease of operation without sacrificing adsorption capacity.

The patent employs an organic binder during the molding process that is intentionally designed to be temporary and decomposable. The binder facilitates manufacturing by holding the zeolite and inorganic material together during formation, but is completely decomposed and removed during the firing process. This leaves no organic residue that would compromise insulation performance, thus achieving both ease of manufacture and maintained reliability.

The patent optimizes the molding density parameter to a specific range (0.9 to 1.4 g/cm³) that balances two competing requirements. At this optimized density, the compact has sufficient mechanical strength and low dust generation for good handling characteristics, while simultaneously maintaining adequate porosity (40-60%) to preserve gas adsorption capacity. This parameter optimization resolves the contradiction between handling ease and adsorption performance.