The aluminum powder used for the pigment means that the particles are scaly, and it is very easy to use after the surface coating treatment, so the output and dosage are relatively large.

Compared with other pigments, aluminum pigments have more characteristics, which are shown in the following aspects:

1. The characteristics of scaly covering. The aluminum powder particles are scaly, and the ratio of the diameter to the thickness is about (40:1)-(100:1). After the aluminum powder is dispersed into the carrier, it has the characteristic of being parallel to the substrate. The aluminum powder is connected to each other, and the large and small particles fill each other to form a continuous metal film, which covers the substrate and reflects the light outside the coating film. This is the unique hiding power of aluminum powder. The hiding power of aluminum powder depends on the surface area, which is the diameter-to-thickness ratio. Aluminum is stretched during the grinding process, and the diameter-to-thickness ratio continues to increase, and the hiding power also increases.

2. The shielding characteristics of aluminum powder. The aluminum powder dispersed in the carrier floats. The result of its movement is always to make itself parallel to the substrate coated by the carrier to form a continuous aluminum powder layer. Multiple layers are arranged in parallel in the carrier film. The pores between the layers of aluminum powder are staggered, cutting off the capillary pores of the carrier film, and external moisture and gas cannot pass through the capillary pores to reach the substrate. This feature is the good physical shielding of the aluminum powder.

3. The characteristics of light reflection of aluminum powder. Aluminum powder is made of aluminum with light color and high metallic luster. The surface is smooth and can reflect 60%-90% of visible light, ultraviolet light and infrared light. It is coated with paint containing aluminum powder. The surface of the object is silvery white and bright.

4. The "dual-color effect" characteristics of aluminum powder. Aluminum powder has the characteristics of metallic luster and parallel to the coated object. In a carrier containing transparent pigments, the gloss and color depth of aluminum powder vary with the incident angle and viewing angle of the incident light. The change of light and color occurs, and this characteristic is called the "two-color effect". The aluminum powder is arranged in different levels in the coating film. When the incident light illuminates each layer of aluminum flakes, the coating film of different thickness is weakened differently, and the reflected light is obviously different in brightness. When light enters the film containing transparent pigments and aluminum powder, the incident light passes through the pigment particles to become colored light, and then is reflected by different levels of aluminum powder, and changes in color tone and metallic light will occur, incident light and viewing angle From vertical, the angular position shifts gradually, and the light passes through pigments of different particle numbers and aluminum powders of different particle sizes, and the color tone and metallic light of the reflected light also undergo infinite changes. This characteristic of aluminum powder has been widely used in coatings as hammer paint or metallic paint.

5. Floating characteristics of aluminum powder. A large type of aluminum pigment powder is floating type, which is characterized by scaly floating on the surface of the coating film.