Patent ID: 7681299

Claim:
A method of insulating an article having first and second walls spaced at a distance from each other to define an insulating space therebetween, the method comprising: providing a vent in communication with the insulating space; providing an exit pathway for gas molecules to exit from the insulating space through the vent by varying the distance between the first and second walls in a portion of the insulating space proximate to the vent such that gas molecules are guided towards the vent when a vacuum is applied to the vent; placing the article in a vacuum chamber to apply a vacuum to the vent, wherein the vacuum applied to the vent is sufficiently low that molecule-to-molecule interactions within the insulating space no longer dominate; generating a vacuum within the insulating space that is deeper than the vacuum applied to the vent as a result of the exit pathway increasing the probability of gas molecule egress from the insulating space as compared with the probability of gas molecule ingress into the insulating space; and sealing the vent to maintain the deeper vacuum within the insulating space.