Aluminum foil can be divided into rigid foil, semi-hard foil and soft foil according to the temper.
Hard foil:
The aluminum foil that has not been softened (annealed) after rolling, and has no residue on the surface when it is not degreasing. Therefore, the hard foil must be degreased before printing, lamination, and coating, and it can be used directly if it is used for forming.
Semi-hard foil:
aluminum foil whose hardness (or strength) is between hard foil and soft foil, usually used for forming.
Soft foil:
Aluminum foil that has been fully annealed and softened after rolling. The material is soft and there is no residual oil on the surface. Most applications, such as packaging, lamination, electrical materials use flexible foils.
Classification according to the surface state
Aluminum foil can be divided into single sided smooth aluminum foil and both sided smooth aluminum foil according to the surface state.