METHOD OF PRODUCING DIELECTRIC LAYER ON ALUMINIUM SUBSTRATE SURFACE Russian patent published in 2019 - IPC C25D11/04 H05K1/05 

FIELD: chemistry.

SUBSTANCE: invention relates to production of dielectric layer on surface of aluminium substrate. Technical result is achieved by the fact that dielectric layer is formed by deep porous anodic oxidation of aluminium (anodizing) in acidic solution at anode value of 40–120 V. Anodizing is carried out in two stages. First anodizing step is 20–60 minutes. Then, the second anodizing step is carried out with the second anodic parameters. At the second stage, the first at least 20 % of the anodizing time use a voltage equal to the anodic strain at the first stage, and the rest of not more than 80 % of the time voltage is smoothly increased to value 1.5–2 times higher compared to the voltage at the first anodizing step with obtaining pores of variable diameter along their length. Duration of the second anodizing step is 170–250 minutes. Pores of obtained anode porous aluminium oxide are impregnated with dielectric material using ultrasound.

EFFECT: providing uniform distribution of dielectric material in pores of anodic aluminium oxide, which allows to increase breakdown voltage.

12 cl, 7 dwg, 1 tbl, 5 ex