CN109161881B - Chromium-free anti-oxidation liquid and washing-free anti-oxidation process for electrolytic copper foil - Google Patents
Chromium-free anti-oxidation liquid and washing-free anti-oxidation process for electrolytic copper foil Download PDFInfo
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- CN109161881B CN109161881B CN201811101186.4A CN201811101186A CN109161881B CN 109161881 B CN109161881 B CN 109161881B CN 201811101186 A CN201811101186 A CN 201811101186A CN 109161881 B CN109161881 B CN 109161881B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/40—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates
- C23C22/42—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates containing also phosphates
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D1/00—Electroforming
- C25D1/04—Wires; Strips; Foils
Abstract
The invention provides a chromium-free anti-oxidation liquid for electrolytic copper foil, which comprises the following components: 5-9g/L of sodium tungstate, 1-3g/L of hydroxyethylidene diphosphonic acid, 4-7g/L of disodium ethylene diamine tetraacetate and 1-3ml/L of phosphoric acid. The chromium-free anti-oxidation liquid does not contain a chromium element which is carcinogenic to a human body and a zinc simple substance which reduces the performance of the battery, does not need to be washed, does not generate waste water to pollute the environment in the working procedure, is environment-friendly and saves the cost. The invention also provides a washing-free anti-oxidation process using the chromium-free anti-oxidation liquid, a passivation film formed by the process is kept consistent, good wettability and conductivity of the electrolytic copper foil are ensured, the operation is simple, the control is convenient, a washing procedure is reduced, the energy consumption is saved, and no wastewater polluting the environment is generated.
Description
Technical Field
The invention relates to the technical field of electrolytic copper foil manufacturing, in particular to a chromium-free anti-oxidation liquid, namely a washing-free anti-oxidation process, of an electrolytic copper foil.
Background
The conventional electrolytic copper foil raw foil manufacturing process mainly comprises the following steps: the method comprises the steps of copper foil generation, copper foil stripping, drying, anti-oxidation treatment, water washing, water extrusion, drying before rolling and rolling. In the process of anti-oxidation treatment, the prior anti-oxidation agent is generally acid chromate, and after the metal is contacted with a chromate passivating agent, the surface is partially dissolved and reprecipitated in the form of metal-chromium oxide.
The production process has long distance, and the appearance problems of cockling, water spots, color difference and the like are easy to occur when the ultrathin electrolytic copper foil is produced. Moreover, the chromium-containing anti-oxidation passivation solution has the following defects and shortcomings:
(1) contains chromium element which can cause cancer to human body and harm the body of the operator; (2) after the copper foil is used, some copper foil products need to be dried by a high-temperature oven, and the high temperature causes the temperature of a sealed rolling room to be extremely high, so that the copper foil products are not suitable for personnel to operate; (3) an anode plate is added to the smooth surface and the hair surface of the copper foil in the anti-oxidation groove, and certain current is supplied to ensure the anti-oxidation requirement; (4) some anti-oxidation passivation solutions contain zinc, metal zinc is formed on the surface of copper foil after electrodeposition, and a zinc simple substance can form a primary battery under electrolyte in the battery, so that the capacity and the charge-discharge performance of the battery are reduced, and even explosion is caused.
In addition, after the chromium-containing anti-oxidation passivation solution is used for anti-oxidation treatment, the chromium-containing anti-oxidation passivation solution needs to be washed with water, a washing device comprises 1 pump and 4 spray pipes, a large amount of electric energy and industrial water need to be consumed, waste water can be generated subsequently, the environment is polluted, and the water treatment cost is increased.
In order to save cost and protect environment, the prior oxidation-preventing passivating agent and water washing process need to be optimized and improved.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a chromium-free anti-oxidation liquid which does not contain a chromium element which is carcinogenic to a human body and a zinc simple substance which reduces the performance of a battery, does not need to be washed, does not generate wastewater to pollute the environment in the working procedure, is environment-friendly and saves the cost. The invention also provides a washing-free anti-oxidation process using the chromium-free anti-oxidation liquid, a passivation film formed by the process is kept consistent, good wettability and conductivity of the electrolytic copper foil are ensured, the operation is simple, the control is convenient, a washing procedure is reduced, the energy consumption is saved, and no wastewater polluting the environment is generated.
In order to achieve the purpose, the invention provides the following technical scheme:
a chromium-free anti-oxidation liquid for electrolytic copper foil comprises the following components: 5-9g/L of sodium tungstate, 1-3g/L of hydroxyethylidene diphosphonic acid, 4-7g/L of disodium ethylene diamine tetraacetate and 1-3ml/L of phosphoric acid.
In the chromium-free anti-oxidation liquid, the addition of sodium tungstate can improve the surface roughness of the copper foil, so that a uniform passivation film is formed in the anti-oxidation treatment process.
Hydroxyethylidene diphosphonic acid, HEDP for short, is an organic phosphoric acid scale and corrosion inhibitor which can form a stable complex with iron, copper, zinc and other metal ions and can dissolve oxides on the metal surface. Research shows that HEDP can still play a good role in corrosion and scale inhibition at 250 ℃, is stable at a high pH value, is not easy to hydrolyze, and is not easy to decompose under the common photo-thermal condition. The acid and alkali resistance and the chlorine and oxidation resistance are better than those of other organic phosphates. HEDP can form a six-ring chelate with metal ions in water, especially calcium ions, so HEDP has a good scale inhibition effect and an obvious solubility limit effect, and shows an ideal synergistic effect when being used in combination with other water treatment agents.
Disodium ethylenediaminetetraacetate, abbreviated as EDTA-2Na, is a good complexing agent in chemistry, has six coordinating atoms, and forms stable chelates with almost all metal ions.
The main function of the phosphoric acid is to adjust the pH value in the anti-oxidation liquid, so that the anti-oxidation liquid can play an anti-oxidation and passivation role under a proper pH condition.
According to the invention, through selecting the components and optimizing the proportion, sodium tungstate, hydroxyethylidene diphosphonic acid, disodium ethylene diamine tetraacetate and phosphoric acid are prepared in the same solution system and cooperate with each other to form a uniform polymeric complex film on the surface of the electrolytic copper foil, and the passivation film is stable and insoluble in a plurality of solvents and has good corrosion resistance protection effect.
As a further description of the technical solution of the present invention, the following components are included: 6g/L of sodium tungstate, 2g/L of hydroxyethylidene diphosphonic acid, 5g/L of disodium ethylene diamine tetraacetate and 2ml/L of phosphoric acid.
As a further description of the technical solution of the present invention, the pH of the chromium-free anti-oxidation solution is 2 to 4, and the inventors found that when the pH of the anti-oxidation solution is controlled to 2 to 4, a passivation film formed on the surface of the copper foil is uniform and has no color difference.
The invention also provides a washing-free anti-oxidation process adopting the chromium-free anti-oxidation liquid, which comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
the foil generating equipment comprises a cathode roller, an anode tank, a transmission and control system, a rectification system, a conductive system, a liquid supply pipeline and the like. The specific foil-producing process is that a rotary cathode roller and an insoluble material supported anode are arranged in an electrolytic bath, the bottom of the roller is immersed in electrolyte, and after electrification, copper ions in the solution are deposited on the surface of the roller to form a copper foil.
(2) And (3) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas.
The hot air drying device comprises an air heater, a hot air pipeline, an air outlet pipe and an acid mist blocking shield provided with an air draft interface, so that the copper foil can be ensured not to contain water before being stripped, and acid gas can be effectively extracted.
(3) And (3) anti-oxidation treatment: the chromium-free anti-oxidation liquid is adopted for anti-oxidation passivation treatment, and comprises the following components: 5-9g/L of sodium tungstate, 1-3g/L of hydroxyethylidene diphosphonic acid, 4-7g/L of disodium ethylene diamine tetraacetate and 1-3ml/L of phosphoric acid.
(4) Extruding the anti-oxidation liquid by adopting a dead-weight pressurization type liquid extruding method.
(5) Drying, rolling and cutting, packaging after passing quality inspection and leaving factory.
The drying equipment before rolling comprises a drying oven, a far infrared radiation heating tube, an axial flow fan and other devices, wherein a water vapor collecting pipeline is arranged on the upper portion and the lower portion of the drying oven, and a gold-plated reflecting layer is arranged on the back face of the far infrared radiation heating tube to enhance far infrared radiation energy and is used for drying the copper foil before rolling. And a small-sized inflatable roller is adopted for rolling, so that the rim charge is convenient to disassemble.
As further description of the technical scheme of the invention, the anti-oxidation passivation treatment time is 6s, and the temperature is 24-26 ℃.
By adopting the chromium-free anti-oxidation process, the produced electrolytic copper foil anti-oxidation passivation film is uniform, and a good anti-oxidation effect can be achieved without washing, thereby avoiding the generation of Cr-containing wastewater, reducing the wastewater treatment cost and emission, realizing clean production and reducing the pollution to the environment.
Based on the technical scheme, the invention has the following technical effects:
(1) the chromium-free anti-oxidation liquid for the electrolytic copper foil does not contain a chromium element which is carcinogenic to a human body and a zinc simple substance which reduces the performance of a battery, can form a uniform polymeric complex film on the surface of the electrolytic copper foil, is stable and insoluble in a plurality of solvents, and has a good corrosion-resistant protection effect.
(2) The chromium-free anti-oxidation liquid is used for carrying out anti-oxidation passivation on the electrolytic copper foil, the appearance quality of the copper foil is improved, the appearance problems of water spots, color difference and the like are avoided, and the higher wettability and the higher conductivity of the electrolytic copper foil are maintained due to the uniform and consistent passivation film.
(3) The anti-oxidation process of the chromium-free anti-oxidation liquid provided by the invention adopts the chromium-free anti-oxidation liquid with the optimized components, does not need water washing, reduces one procedure in the production process of the electrolytic copper foil, saves the production cost, does not generate chromium-containing wastewater, and is environment-friendly and free from environment pollution.
Detailed Description
In order that the invention may be more fully understood, reference will now be made to the specific embodiments illustrated. The invention provides a preferred embodiment. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
Example 1
A chromium-free anti-oxidation liquid for electrolytic copper foil comprises the following components: 6g/L of sodium tungstate, 2g/L of hydroxyethylidene diphosphonic acid, 5g/L of disodium ethylene diamine tetraacetate and 2ml/L of phosphoric acid; wherein, the pH value of the chromium-free anti-oxidation liquid is 3.
The washing-free anti-oxidation process of the chromium-free anti-oxidation liquid comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
(2) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas;
(3) and (3) anti-oxidation treatment: carrying out anti-oxidation passivation treatment by adopting the chromium-free anti-oxidation liquid, wherein the treatment time is 6s, and the temperature is controlled to be 25 ℃;
(4) extruding the anti-oxidation liquid;
(5) drying, rolling and cutting, packaging after passing quality inspection and leaving factory.
Example 2
A chromium-free anti-oxidation liquid for electrolytic copper foil comprises the following components: 5g/L of sodium tungstate, 1g/L of hydroxyethylidene diphosphonic acid, 4g/L of disodium ethylene diamine tetraacetate and 1ml/L of phosphoric acid; wherein, the pH value of the chromium-free anti-oxidation liquid is 4.
The washing-free anti-oxidation process of the chromium-free anti-oxidation liquid comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
(2) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas;
(3) and (3) anti-oxidation treatment: carrying out anti-oxidation passivation treatment by adopting the chromium-free anti-oxidation liquid, wherein the treatment time is 6s, and the temperature is controlled to be 24 ℃;
(4) extruding the anti-oxidation liquid;
(5) drying, rolling and cutting, packaging after passing quality inspection and leaving factory.
Example 3
A chromium-free anti-oxidation liquid for electrolytic copper foil comprises the following components: 9g/L of sodium tungstate, 3g/L of hydroxyethylidene diphosphonic acid, 7g/L of disodium ethylene diamine tetraacetate and 3ml/L of phosphoric acid; wherein, the pH value of the chromium-free anti-oxidation liquid is 2.
The washing-free anti-oxidation process of the chromium-free anti-oxidation liquid comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
(2) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas;
(3) and (3) anti-oxidation treatment: carrying out anti-oxidation passivation treatment by adopting the chromium-free anti-oxidation liquid, wherein the treatment time is 6s, and the temperature is controlled to be 26 ℃;
(4) extruding the anti-oxidation liquid;
(5) drying, rolling and cutting, packaging after passing quality inspection and leaving factory.
Example 4
A chromium-free anti-oxidation liquid for electrolytic copper foil comprises the following components: 7g/L of sodium tungstate, 2g/L of hydroxyethylidene diphosphonic acid, 5g/L of disodium ethylene diamine tetraacetate and 2ml/L of phosphoric acid; wherein, the pH value of the chromium-free anti-oxidation liquid is 3.
The washing-free anti-oxidation process of the chromium-free anti-oxidation liquid comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
(2) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas;
(3) and (3) anti-oxidation treatment: carrying out anti-oxidation passivation treatment by adopting the chromium-free anti-oxidation liquid, wherein the treatment time is 6s, and the temperature is controlled to be 25 ℃;
(4) extruding the anti-oxidation liquid;
(5) drying, rolling and cutting, packaging after passing quality inspection and leaving factory.
Comparative example
After the copper foil is stripped, the electrolytic copper foil enters an anti-oxidation passivation solution only containing 5g/L of ethylene diamine tetraacetic acid through a guide roller, wherein the temperature is controlled to be 25 ℃, the treatment time is 6s, and the electrolytic copper foil is dried at high temperature and then wound.
The products of examples 1 to 4 and comparative example were subjected to the oxidation prevention test, and the test results were as follows:
table 1 results of oxidation resistance test conducted on copper foil products of examples 1 to 4 and comparative example
It can be seen from the test results in table 1 that the oxidation-preventing passivation solution of disodium ethylenediaminetetraacetate is only used, and almost no protection effect is provided to the copper foil, while the copper foil using the chromium-free oxidation-preventing solution has a good oxidation-preventing effect, mainly because the oxidation-preventing solutions of examples 1 to 4 can prepare sodium tungstate, hydroxyethylidene diphosphonic acid, disodium ethylenediaminetetraacetate and phosphoric acid in the same solution system, and cooperate with each other, so as to form a uniform polymeric complex film on the surface of the electrolytic copper foil, and the passivation film is stable and insoluble in many solvents, and has a good corrosion-resistant protection effect.
The foregoing is merely exemplary and illustrative of the structures of the present invention, which are described in some detail and detail, and are not to be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications are possible without departing from the inventive concept, and such obvious alternatives fall within the scope of the invention.
Claims (1)
1. A washing-free anti-oxidation process of a chromium-free anti-oxidation liquid by adopting an electrolytic copper foil is characterized in that the chromium-free anti-oxidation liquid comprises the following components: 5-9g/L of sodium tungstate, 1-3g/L of hydroxyethylidene diphosphonic acid, 4-7g/L of disodium ethylene diamine tetraacetate and 1-3ml/L of phosphoric acid; the pH value of the chromium-free anti-oxidation liquid is 2-4;
the washing-free anti-oxidation process comprises the following steps:
(1) depositing copper ions in the electrolyte on the surface of the roller to form a copper foil;
(2) stripping the copper foil, drying by adopting a hot air drying device before stripping, and effectively pumping acid gas;
(3) and (3) anti-oxidation treatment: carrying out anti-oxidation passivation treatment by adopting the chromium-free anti-oxidation liquid;
(4) extruding the anti-oxidation liquid;
(5) drying, rolling and slitting, packaging after passing quality inspection, and leaving the factory;
the anti-oxidation passivation treatment time is 6s, and the temperature is 24-26 ℃;
the hot air drying device comprises an air heater, a hot air pipeline, an air outlet pipe and an acid mist shielding shield provided with an air draft interface.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811101186.4A CN109161881B (en) | 2018-09-20 | 2018-09-20 | Chromium-free anti-oxidation liquid and washing-free anti-oxidation process for electrolytic copper foil |
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| CN201811101186.4A CN109161881B (en) | 2018-09-20 | 2018-09-20 | Chromium-free anti-oxidation liquid and washing-free anti-oxidation process for electrolytic copper foil |
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| CN109161881B true CN109161881B (en) | 2021-02-12 |
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| CN110344043A (en) * | 2019-07-05 | 2019-10-18 | 国工恒昌新材料沧州有限公司 | A kind of processing of lead frame copper strip plate curing means and maintenance process |
| CN111472005B (en) * | 2020-04-27 | 2022-05-24 | 青海电子材料产业发展有限公司 | Acidic environment-friendly anti-oxidation process for electrolytic copper foil |
| CN112095108A (en) * | 2020-08-11 | 2020-12-18 | 湖北工程学院 | Electrolytic copper foil antioxidant and anti-oxidation process using same |
| CN113564572A (en) * | 2021-08-04 | 2021-10-29 | 武汉轻工大学 | Preparation and application of novel electrolytic copper foil anti-oxidation liquid |
| CN113463078B (en) * | 2021-08-04 | 2023-10-27 | 武汉轻工大学 | Preparation method and application of antioxidant liquid containing polyhydroxy organic matters |
| CN116333593A (en) * | 2023-03-22 | 2023-06-27 | 江苏铭丰电子材料科技有限公司 | Environment-friendly anti-oxidation liquid for electrolytic copper foil and anti-oxidation process thereof |
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| CN100585004C (en) * | 2008-02-28 | 2010-01-27 | 武汉钢铁(集团)公司 | The chromium-free passivation liquid that is used for galvanized steel sheet surface |
| CN102747372B (en) * | 2011-04-22 | 2014-09-17 | 比亚迪股份有限公司 | Copper protective agent and its preparation method and copper protection method |
| CN104342681A (en) * | 2014-09-22 | 2015-02-11 | 东莞市凯盟表面处理技术开发有限公司 | Passivating film formation liquid and application thereof |
| CN107634228A (en) * | 2017-09-14 | 2018-01-26 | 江苏铭丰电子材料科技有限公司 | A kind of lithium ion battery electrolytic copper foil Chrome-free anti-oxidation technology |
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