Gelid has been around for quite a while now and have been the go to solution for thermal pads and paste for many enthusiasts.
Gelid has now come out with the new HeatPhase Ultra thermal pads for AMD and Intel CPUs. The thermal pads are a phase change material (PCM). This allows the thermal pad to offer high performance, super long durability without drying out or crumbling and, best of all, does not exhibit thermal pump out.
For those who are new to the scene, thermal pump out is when the heatsink or coldplate expands and contracts over time due to thermal cycles. Eventually, this movement causes the thermal paste to be "pumped" out away from the core. As a result, thermal performance drops over time and some thermal pastes exhibit this phenomenon more than others.