Solar reflecting film and preparation method thereof

A solar reflecting film, comprising a substrate and a functional layer, the functional layer comprising a first reflecting layer, a barrier layer and a second reflecting layer stacked on the substrate in order;

• wherein the barrier layer comprises a first barrier layer and a second barrier layer stacked on the first barrier layer;
• the first barrier layer is metal fluoride, inorganic non-metallic oxide, metal oxide or a combination thereof;
• the second barrier layer is metal oxides, metal nitrides, semiconductor doped compounds or a combination thereof;
• and
• a material of the first barrier layer is at least partially different from that of the second barrier layer,
• the barrier layer further comprises a third barrier layer between the first barrier layer and the second barrier layer, a material of the third barrier layer is metal fluoride, inorganic non-metal oxide, metal oxide, metal nitride, semiconductor doping compound, or a combination thereof, and
• a material of the third barrier layer is at least partially different from that of the first barrier layer and that of the second barrier layer.