Aluminum foil products can be divided into the following categories.
(1) By shape
Aluminum foil is divided into roll aluminum foil and sheet aluminum foil according to its shape. The vast majority of aluminum foil products are in roll form, and only a very small number of handicraft packaging users use sheet aluminum foil.
(2) By thickness
Aluminum foil is generally divided into double foil and single foil according to its thickness. Generally, manufacturers call aluminum foil with a thickness of less than or equal to 0.012mm double foil, and aluminum foil with a thickness greater than 0.012mm single foil.
(3) By state
Aluminum foil is classified into full hard foil, soft foil, semi-hard foil, quarter hard foil and three-quarter hard foil according to its state.
① Full hard foil. Refers to aluminum foil that has not been annealed after rolling (fully annealed material and cold-rolled by more than 75%). Due to the lack of annealing, there is residual oil on the surface of the aluminum foil. The application areas include processing aluminum foil utensils, decorative foil, medicinal foil, etc.
② Soft foil. Refers to aluminum foil that has become soft after full annealing after rolling. Due to full annealing, the tensile strength of the aluminum foil is reduced, the elongation is increased, the material is soft, and there is no residual oil on the surface. The application areas include composite packaging materials such as food and cigarettes, and the electrical industry.
③ Semi-hard foil. Refers to aluminum foil whose tensile strength is between full hard foil and soft foil. The application areas include air conditioning foil, bottle cap materials, etc.
④ Three-quarter hard foil. Refers to aluminum foil whose tensile strength is between full hard foil and semi-hard foil. Application areas include air conditioning foil, aluminum-plastic pipe foil, etc.
⑤ Quarter-hard foil. Refers to aluminum foil with a tensile strength between soft foil and semi-hard foil, and its application areas include air conditioning foil, etc.
(4) By surface state
Aluminum foil is classified into single-sided smooth foil and double-sided smooth foil according to its surface state. Aluminum foil rolling is divided into single sheet rolling and double sheet rolling. When single sheet rolling is carried out, the upper and lower sides of the aluminum foil are in contact with the rollers, and both sides have a bright metallic luster. This kind of foil is called double-sided smooth foil. When double sheet rolling is carried out, only one side of each foil is in contact with the rollers. The surface in contact with the rollers and the surface in contact with each other of the aluminum foils have different surface brightness. The surface in contact with the rollers is bright, and the surface in contact with each other of the aluminum foils is dark. This kind of aluminum foil is called single-sided smooth foil.
The minimum thickness of double-sided smooth aluminum foil mainly depends on the diameter of the working roller, which is generally not less than 0.01mm. The thickness of single-sided smooth aluminum foil is generally not more than 0.03mm.
(5) By use
Aluminum foil is mainly classified into packaging foil, daily necessities foil, electrical equipment foil and construction foil according to its use.
