CN110783108A - Method for manufacturing corrosion foil - Google Patents

Abstract

The invention discloses a method for manufacturing an etched foil, which comprises five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-processing on high-purity aluminum foil. The pretreatment includes: immersing the aluminum foil in the pretreatment solution for 60-70s; after cleaning, placing it in a primary corrosion mixture with a temperature of 70-85°C, and applying a direct current with a current density of 1800mA/cm ² for electrolysis Corrosion for 65‑75s, clean with pure water, put it into a temperature of 60‑90℃, put it in a hydrochloric acid solution containing 10%‑12%, chemically corrode for 300‑400s; Drying in an oven at 150 °C; simple pretreatment process and convenient operation. The two processing steps of porosity corrosion are adjusted to make the porosity effect uniform, greatly reduce the dispersion rate of the corrosion foil for aluminum electrolytic capacitors, and improve the bending performance. The post-processing steps are improved so that annealing is not required, enabling continuous production of etched foils.

Description

A kind of manufacturing method of corroded foil

technical field

The invention relates to the technical field of corrosion foil production, in particular to a manufacturing method of corrosion foil.

Background technique

The prior art discloses a manufacturing process of a medium corrosion foil, which includes five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-processing of high-purity aluminum foil. The method described in the pretreatment is to put the aluminum foil into the corrosion foil and soak it in the pretreatment solution for 40-50s; then clean it, put it in a primary corrosion mixture with a temperature of 80-90°C, and clean it with pure water The temperature is 70-80 ° C, put into a nitric acid bath containing 2%, and the direct current with a current density of 0.15 A/cm ² is applied for electrolytic corrosion for 500-600s; the post-treatment adopts two stages Different temperature annealing heat treatment, the pretreatment process of the present invention is simple, the operation is convenient, and no deformation occurs, and the annealing process is improved in the post treatment. Bending properties of etched foils for capacitors. However, the annealing heat treatment process is complex, cannot realize automatic industrial production, and has no practicability.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for manufacturing an etched foil, so as to solve one or more technical problems existing in the prior art, and at least provide a beneficial option or create conditions.

The technical solutions adopted to solve the above technical problems:

A manufacturing method of etched foil includes five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-processing on high-purity aluminum foil. Specifically include:

Pretreatment: Soak the aluminum foil in the pretreatment solution for 60-70s; then clean it and place it in a primary corrosion mixture with a temperature of 70-85℃, and apply a direct current with a current density of 1800mA/cm ² for electrolytic corrosion 65-75s, rinse with pure water, put it at a temperature of 60-90°C, put it in a hydrochloric acid solution containing 10%-12%, and chemically corrode it for 300-400s; ℃ oven for drying;

First-level pore corrosion: put the pre-treated aluminum foil in the first-level pore etching solution at a temperature of 70-85 °C, and apply a direct current with a current density of 1500-2100mA/cm ² to conduct pore corrosion for 65-75s. The pore etching solution is a mixed solution containing 1-3% hydrochloric acid and 6-10% sulfuric acid in mass percentage;

Secondary porosity corrosion: Put the aluminum foil after primary porosity corrosion in the secondary porosity corrosion solution at a temperature of 80-85°C, and apply a direct current with a current density of 300-400mA/cm ² to conduct porosity corrosion for 200- 300s;

Pore Enlarging Corrosion: Put the aluminum foil after secondary porosity corrosion in the hole enlarging etching solution at a temperature of 60-90 ℃, and carry out chemical hole enlarging corrosion for 300-400s;

Post-treatment: Soak the aluminum foil after hole expansion and corrosion in nitric acid solution at a temperature of 50-80 °C.

Wherein, the first-stage pore etching solution in the first-stage pore etching step contains a complexing agent, specifically polybenzenesulfonic acid or sodium polybenzenesulfonate, with a molecular weight of 50,000. When the aluminum foil has completed the first-level pore corrosion, it is taken out from the etching solution tank, and it is sprayed with the first-level pore etching solution, and the spray flow rate is 18L/h.

Preferably, the secondary porosity etching solution is a solution of 0.5-1% nitric acid by mass. When the aluminum foil has completed the secondary porosity corrosion, after taking it out of the etching solution tank, it is sprayed with the secondary porosity corrosion solution, and the spray flow rate is 18L/h.

Preferably, the hole-enlarging etching solution is a hydrochloric acid solution with a mass percentage of 10-12%.

Preferably, the nitric acid solution used in the post-treatment is a solution of 2% nitric acid by mass.

Compared with the prior art, the beneficial effects of the present invention are:

The pretreatment process is simple and the operation is convenient. The two processing steps of porosity corrosion are adjusted to make the porosity effect uniform, greatly reduce the dispersion rate of the corrosion foil for aluminum electrolytic capacitors, and improve the bending performance. The post-processing steps are improved so that annealing is not required, enabling continuous production of etched foils.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

In the embodiment of the present invention, a method for manufacturing an etched foil includes five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-treatment on high-purity aluminum foil, and the pre-treatment is as follows: Immerse the aluminum foil in the pretreatment solution for 60s; then clean it and place it in a primary corrosion mixture with a temperature of 70°C, apply a direct current with a current density of 1500mA/cm ² for electrolytic corrosion for 65s, and clean it with pure water Put it into a 10% hydrochloric acid solution at a temperature of 60°C, and carry out chemical corrosion for 300s; finally, clean it with pure water and then put it into an oven with a temperature of 100°C for drying.

Wherein, in the first-stage pore corrosion, the pre-treated aluminum foil is placed in a first-stage pore corrosion solution with a temperature of 70°C, and a direct current with a current density of 1500 mA/cm ² is applied to carry out pore corrosion for 65s. The grade porosity etching solution is a mixed solution containing 1% hydrochloric acid and 6% sulfuric acid by mass. When the aluminum foil has completed the first-level pore corrosion, it is taken out from the etching solution tank, and it is sprayed with the first-level pore etching solution, and the spray flow rate is 18L/h.

The secondary pore corrosion is to place the aluminum foil after primary pore corrosion in a secondary pore etching solution with a temperature of 80°C, and apply a direct current with a current density of 300 mA/cm ² to perform pore corrosion for 200s. The secondary pore etching solution is a solution containing 0.5% nitric acid by mass. When the aluminum foil has completed the secondary porosity corrosion, after taking it out of the etching solution tank, it is sprayed with the secondary porosity corrosion solution, and the spray flow rate is 18L/h.

The said hole expansion corrosion is to put the aluminum foil after the secondary hole corrosion in the hole expansion corrosion solution with a temperature of 60 ° C. The hole expansion corrosion solution is a hydrochloric acid solution with a mass percentage of 10%, and the chemical hole expansion corrosion is carried out for 300s. .

A complexing agent is added to the hole-enlarging etching solution, and the complexing agent is a sulfonic acid-containing compound or a salt thereof.

The sulfonic acid-containing compound or its salt is polybenzenesulfonic acid or sodium polybenzenesulfonate with a molecular mass of 50,000.

The post-treatment is to soak the aluminum foil after hole expansion and corrosion in a solution of 2% nitric acid by mass at a temperature of 50° C. and a time of 50 s.

Comparative Example 1

Compared with Example 1, no spraying was performed, and the rest was the same as Example 1.

Example 2

In the embodiment of the present invention, a method for manufacturing an etched foil includes five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-treatment on high-purity aluminum foil, and the pre-treatment is as follows: Soak the aluminum foil in the pretreatment solution for 65s; then clean it and put it in a primary corrosion mixture with a temperature of 80°C, apply a direct current with a current density of 1800mA/cm ² for electrolytic corrosion for 70s, and clean it with pure water The temperature is 75 ℃, and it is put into a hydrochloric acid solution containing 11%, and chemical corrosion is carried out for 350 s; finally, the pure water is cleaned and then placed in an oven with a temperature of 120 ℃ for drying.

Wherein, in the first-stage pore corrosion, the pre-treated aluminum foil is placed in a first-stage pore corrosion solution with a temperature of 80°C, and a direct current with a current density of 1800 mA/cm ² is applied for 70 s to perform pore corrosion. The grade porosity etching solution is a mixed solution containing 2% hydrochloric acid and 8% sulfuric acid by mass. When the aluminum foil has completed the first-level pore corrosion, it is taken out from the etching solution tank, and it is sprayed with the first-level pore etching solution, and the spray flow rate is 18L/h.

The secondary pore corrosion is to place the aluminum foil after the primary pore corrosion in the secondary pore etching solution with a temperature of 75°C, and apply a direct current with a current density of 350 mA/cm ² to perform pore corrosion for 250s. The secondary pore etching solution is a solution containing 0.8% nitric acid by mass. When the aluminum foil has completed the secondary porosity corrosion, after taking it out of the etching solution tank, it is sprayed with the secondary porosity corrosion solution, and the spray flow rate is 18L/h.

The said hole-enlarging corrosion is to put the aluminum foil after secondary hole-etching in a hole-enlarging etching solution with a temperature of 75°C. The hole-enlarging etching solution is a hydrochloric acid solution with a mass percentage of 11%, and chemical hole-enlarging corrosion is carried out for 350s. .

A complexing agent is added to the hole-enlarging etching solution, and the complexing agent is a sulfonic acid-containing compound or a salt thereof.

The sulfonic acid-containing compound or its salt is polybenzenesulfonic acid or sodium polybenzenesulfonate with a molecular mass of 50,000.

In the post-treatment, the aluminum foil after hole expansion and corrosion is soaked in a solution of 2% nitric acid by mass, the temperature is 65°C, and the time is 50s.

Comparative Example 2

Compared with Example 2, no spraying was performed, and the rest was the same as Example 2.

Example 3

In the embodiment of the present invention, a method for manufacturing an etched foil includes five steps of pre-treatment, primary pore corrosion, secondary pore corrosion, pore expansion corrosion and post-treatment on high-purity aluminum foil, and the pre-treatment is as follows: Soak the aluminum foil in the pretreatment solution for 70s; then clean it and put it in a primary corrosion mixture with a temperature of 85°C, apply a direct current with a current density of 2100mA/cm ² for electrolytic corrosion for 75s, and clean it with pure water Put it into a 12% hydrochloric acid solution at a temperature of 90°C, and carry out chemical corrosion for 400s; finally, clean it with pure water and then put it into an oven with a temperature of 150°C for drying.

Wherein, in the first-stage pore corrosion, the pre-treated aluminum foil is placed in a first-stage pore corrosion solution with a temperature of 85°C, and a direct current with a current density of 2100 mA/cm ² is applied for 75 s to perform pore corrosion. The grade porosity etching solution is a mixed solution containing 3% hydrochloric acid and 10% sulfuric acid by mass. When the aluminum foil has completed the first-level pore corrosion, it is taken out from the etching solution tank, and it is sprayed with the first-level pore etching solution, and the spray flow rate is 18L/h.

The secondary pore corrosion is to place the aluminum foil after primary pore corrosion in the secondary pore etching solution with a temperature of 85°C, and apply a direct current with a current density of 400 mA/cm ² to conduct pore corrosion for 300s. The secondary pore etching solution is a solution containing 1% nitric acid by mass. When the aluminum foil has completed the secondary porosity corrosion, after taking it out of the etching solution tank, it is sprayed with the secondary porosity corrosion solution, and the spray flow rate is 18L/h.

The said hole expansion corrosion is to put the aluminum foil after the secondary hole corrosion in the hole expansion corrosion solution with a temperature of 90°C, and the hole expansion corrosion solution is a hydrochloric acid solution with a mass percentage of 12%, and chemical hole expansion corrosion is carried out for 300s. .

A complexing agent is added to the hole-enlarging etching solution, and the complexing agent is a sulfonic acid-containing compound or a salt thereof.

The sulfonic acid-containing compound or its salt is polybenzenesulfonic acid or sodium polybenzenesulfonate with a molecular mass of 50,000.

In the post-treatment, the aluminum foil after hole expansion and corrosion is soaked in a solution of 2% nitric acid by mass, the temperature is 80° C., and the time is 50s.

Comparative Example 3

Compared with Example 3, no spraying was performed, and the rest was the same as Example 3.

Performance verification

It can be seen from the above results that the specific volume dispersion ratio of the corroded foil is greatly reduced, and the bending strength is greatly improved. The trace elements of the pores will not be processed and will not be deformed. The early effect is ideal, and the surface pore density is uniform and dense, which is conducive to further operations in the later stage. The specific volume dispersion rate is greatly reduced, and the corrosion resistance of aluminum electrolytic capacitors is improved. Bending performance.

It will be apparent to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, but that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the invention is to be defined by the appended claims rather than the foregoing description, which are therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in the present invention.

Claims (9)

1. a preparation method of corroded foil, comprises five steps of pretreatment, primary porosity corrosion, secondary porosity corrosion, hole expansion corrosion and post-processing to aluminum foil, it is characterized in that: 1) Pretreatment: Soak the aluminum foil in the pretreatment solution for 60-70s; then clean it and place it in a primary corrosion mixture with a temperature of 70-85°C, and apply a direct current with a current density of 1800mA/cm ² to carry out the process. Electrolytic corrosion for 65-75s, clean with pure water, put it at a temperature of 60-90℃, put it in a hydrochloric acid solution containing 10%-12%, chemical corrosion for 300-400s; -150℃ oven for drying; 2) Primary pore corrosion: put the pre-treated aluminum foil in a primary pore corrosion solution with a temperature of 70-85 ° C, and apply a direct current with a current density of 1500-2100 mA/cm ² to conduct pore corrosion for 65-75s, The first-level pore etching solution is a mixed solution containing 1-3% hydrochloric acid and 6-10% sulfuric acid in mass percentage; 3) Secondary porosity corrosion: Put the aluminum foil after primary porosity corrosion in the secondary porosity corrosion solution with a temperature of 80-85°C, and apply a direct current with a current density of 300-400mA/cm ² to conduct porosity corrosion. 200-300s; 4) Pore enlarging corrosion: Put the aluminum foil after secondary porosity corrosion in a porosity-enlarging etching solution with a temperature of 60-90 ℃, and carry out chemical porosity-enlarging corrosion for 300-400s; 5) Post-treatment: soak the aluminum foil after hole expansion and corrosion in a nitric acid solution with a temperature of 50-80°C. 2 . The method for manufacturing an etched foil according to claim 1 , wherein the primary porosity etching solution contains a complexing agent, and the complexing agent comprises a xanthate-containing compound or a salt thereof. 3 . 3 . The method for producing an etched foil according to claim 2 , wherein the complexing agent is polybenzenesulfonic acid or sodium polybenzenesulfonate, and the molecular weight is 50,000. 4 . 4 . The method for producing an etched foil according to claim 3 , wherein the aluminum foil processed in step 2) is sprayed with a first-stage pore etching solution before entering step 3). 5 . 5 . The method for manufacturing an etched foil according to claim 1 , wherein the secondary porosity etching solution is a solution of 0.5-1% by mass of nitric acid. 6 . 6 . The method for producing an etched foil according to claim 5 , wherein the aluminum foil processed in step 3) is sprayed with a secondary pore etching solution before entering step 4). 7 . 7 . The method for manufacturing an etched foil according to claim 4 , wherein the spray flow rate of the liquid spray is all 18L/h. 8 . 8 . The method for manufacturing an etched foil according to claim 1 , wherein the hole-enlarging etchant is a hydrochloric acid solution with a mass percentage of 10-12%. 9 . 9 . The method for producing an etched foil according to claim 1 , wherein the nitric acid solution used in the post-treatment is a solution of 2% nitric acid by mass. 10 .