Low-density vacuum heat insulation material and preparation method thereof

The invention provides a low-density vacuum heat insulation material. The low-density vacuum heat insulation material comprises a non-woven fabric bag internally provided with a core material, and a barrier film, the non-woven fabric bag is of a sealed structure, the core material in the non-woven fabric bag is directly placed in the non-woven fabric bag without being subjected to pre-pressing treatment, and the whole non-woven fabric bag containing the core material is subjected to drying, barrier film wrapping and vacuumizing treatment. The non-woven fabric bag is wrapped with the barrier film. According to the preparation method, the core material which is not pressed is directly put into the non-woven fabric bag, the core material does not need to be pre-pressed, the operation procedures can be reduced, and the cost is reduced. And the low-density product is easy to bend, can be slotted, and is suitable for being used in multiple environments and conditions. Meanwhile, after the non-woven fabric bag is fi