What is corrugated and bubble ?

It is watermarks and bubble spots on the surface of material .Such blister products will directly affect the appearance of packaging items and reduce the appearance image of packaging materials .The cause of water ripples is the relationship between the sheet manufactures in the production process,there are water ripples is the production of film speed .Bubble is caused by the high temperature in the production of sheet metal or mixed production of sheet metal or the infiltration of air in the production of sheet metal .the material with bubble will lead to the perforation and deformation of blister packaging products and become defective products.