The invention discloses a PVC blue protective film and a preparation method thereof. The PVC blue protective film comprises a release layer, a blue PVC base film, a priming coat and a pressure-sensitive
adhesive layer which are sequentially arranged from top to bottom. The release layer and the priming coat are respectively designed on the two surfaces of the blue PVC base film, a direct
coating and direct collecting process mode is adopted, an additional release film does not need to be used, the preparation process is simplified, the production cost is reduced, meanwhile, a
plasticizer in the blue PVC base film can be sealed, and the
plasticizer is effectively prevented from being separated out; a direct
coating process instead of a transfer
coating process is adopted, and the base coating is used for clamping, so that the binding strength of the pressure-sensitive
adhesive layer and the blue PVC base film is better; the pressure-sensitive
adhesive layer adopts a slit coating technology, so that the coating thickness is more uniform, rolling is not easy to occur, and the stability of product quality is improved; the resin in the bottom coating can react with the
isocyanate curing agent in the pressure-sensitive adhesive layer, and the resin in the pressure-sensitive adhesive layer can also react with the
isocyanate curing agent in the bottom coating, so that the bonding force between the
layers is enhanced.