a tip seal for use in a scroll - type vacuum pump includes a seal element and an energizer element affixed to the seal element . the scroll - type vacuum pump includes first and second scroll blades that are nested together to define one or more interblade pockets , and an eccentric drive that produces orbiting movement of the first scroll blade relative to the second scroll blade . at least one of the first and second scroll blades has a seal groove along an edge thereof . the tip seal is positioned in the seal groove between the first and second scroll blades . the energizer element is formed of a resilient material having multiple compressible voids , so that the energizer element having compressible voids is more compressible than the resilient material alone , when confined by the seal groove . in one embodiment , the energizer element is a foam such as a low porosity urethane foam . in another embodiment , the energizer element is an elastomer material having a predetermined pattern of voids .