CN1854342A - Method for controlling concentration of peroxide and copper in microetching liquid and its circulative usage - Google Patents
Method for controlling concentration of peroxide and copper in microetching liquid and its circulative usage Download PDFInfo
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- CN1854342A CN1854342A CN 200510031481 CN200510031481A CN1854342A CN 1854342 A CN1854342 A CN 1854342A CN 200510031481 CN200510031481 CN 200510031481 CN 200510031481 A CN200510031481 A CN 200510031481A CN 1854342 A CN1854342 A CN 1854342A
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- etching solution
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Abstract
A method for controlling peroxide concentration and copper concentration in micro-etch solution and its application for recycling. It keeps copper concentration in certain range by separating it selectively and keeps peroxide concentration in required range by electrochemistry technique in micro-etch process. Micro-etch solution produced by this method can be recycled.
Description
Technical field
The present invention relates to the control method of peroxide concentrations in a kind of micro-etching solution, copper concentration and the application in it recycles.
Background technology
Micro-etching solution is that printed-wiring board (PWB) (claims circuit card again, PCB), widely used in the fields such as metal cleaning and surface treatment, five metals processing and electroplating industry, dissolve the solution of pending workpiece surface top material by chemical oxidation or galvanic corrosion mechanism, its objective is the surface coarsening that makes pending workpiece and increase sticking power (bonding force) between itself and the exotic; Micro-etching solution is called microcorrosion liquid again, is pasting dry film operation, plating (copper, lead as printed-wiring board (PWB) (PCB) industry, tin, gold, nickel, palladium, or its alloy etc.) operation, electroless plating (copper, lead, tin, gold, nickel, palladium, or its alloy etc.) all need use micro-etching solution before the operation such as operation, spray tin (slicker solder) operation, to increase the sticking power between workpiece surface (copper-clad plate surface) and exotic such as dry film, electroplating substance or the electroless plating material; The present invention be directed to peroxide type micro-etching solution commonly used, be characterized in containing superoxide, superoxide is to contain peroxide bridge (compound O-O-) such as hydrogen peroxide, persulphate have another name called peroxydisulfate (as ammonium persulphate, Potassium Persulphate and Sodium Persulfate etc.), peroxy acid (claiming Caro's acid CARO ACID again as peroxosulphuric, the peroxide organic carboxyl acid), peroxy-monosulfate (as potassium hydrogen peroxymonosulfate) etc.Can be also can be the mixture of multiple superoxide in actual the use with a kind of superoxide.In micro-etching solution uses, the copper concentration in its solution is controlled in certain scope, as≤40g/L, best≤24g/L; Superoxide total concn in its solution is controlled in certain scope, as (peroxide radical content) 〉=2.5g/L; Copper concentration is too high, or the superoxide total concn when too low the microetch effect of micro-etching solution just can't reach the requirement of some technologies, face and scrap, be i.e. output Liquid wastes (useless micro-etching solution).Because its high toxicity and complicacy, the useless micro-etching solution of discharge belong to State Environmental Protection Administration's dangerous liquid refuse category qualitatively, forbid transboundary movement.For this class dangerous liquid refuse, serious environment pollution directly discharges in the small-sized PCB enterprise that has; It is that the recycling of starting point is as processing copper sulfate etc. that bigger PCB enterprise or waste treatment unit have then carried out to carry copper, but the further output number of course of processing meeting decuples the trade effluent of useless microetch liquid measure, copper concentration wherein generally is higher than the wastewater discharge standard of State Bureau of Environmental Protection, and the non-copper component in the useless micro-etching solution is not more taked control measures targetedly.Therefore, processing after micro-etching solution is scrapped at present or governance process are one makes the further process of diffusion of source of pollution, and water resources and ecotope are damaged.
Summary of the invention
The present invention is from pollution prevention (being cleaner production) rather than does not hold the thinking of administering, copper concentration and peroxide concentrations in the micro-etching solution are control effectively, they always are in the desired scope of microetch process, promptly adopt the method for selective separation copper that the copper concentration in the micro-etching solution is controlled in the scope of processing requirement, as≤24g/L; The method that adopts the method for the online generation superoxide of electrochemistry or add superoxide maintains in the desired peroxide concentrations of microetch technology (peroxide radical content) scope superoxide in the micro-etching solution, as 〉=2.5g/L.After the method for above-mentioned selective separation copper is carried out certain process combination with the method for keeping peroxide concentrations in the micro-etching solution, can realize recycling of micro-etching solution.
An object of the present invention is, the copper concentration in the micro-etching solution is control effectively, it always is in the desired scope of microetch process.Micro-etching solution is a solution widely used in the fields such as processing of printed-wiring board (PWB) (PCB), metal cleaning and surface treatment, five metals and electroplating industry, increase the sticking power (bonding force) between itself and the exotic by the surface coarsening that makes pending workpiece; Be called microcorrosion liquid etc. again, as the micro-etching solution of PCB industry use before pasting dry film operation, electroplating work procedure, electroless plating operation and spray tin operations such as (slicker solders); A technical characterictic of micro-etching solution is only faint corrosion (as depth of corrosion 0.2-3.5 micron) rather than degree of depth corrosion (as 8-15 micrometer depth or more corrosion etc.) to be carried out in the surface of processed workpiece, more is not whole dissolvings.
Another object of the present invention is that the concentration of keeping superoxide in the micro-etching solution makes it always can satisfy the requirement of microetch process in certain scope.When the method with selective separation copper is after effective control method of copper concentration in the micro-etching solution and the method for keeping peroxide concentrations in the micro-etching solution are carried out certain process combination, can make micro-etching solution realize recycling, and make the form output of isolating copper with metallic copper, the suspicion of non-secondary pollution.
By first aspect of the present invention, the copper concentration in the micro-etching solution controlled have following feature:
(1) micro-etching solution is the peroxide type micro-etching solution, and the industry of using of its first-selection is industry of printed circuit boards.
(2) span of control of the copper concentration in the micro-etching solution is: copper≤40g/L, preferable range is copper≤24g/L.
(3) method of copper concentration is following selective separation copper method in the said control micro-etching solution: or solvent extration, or film-electrodip process, or the precipitator method; Or the arbitrary combination of these three kinds of methods.
Solvent extraction wherein is conventional phase disengagement method, is about to pending micro-etching solution and contacts with the organic phase that contains copper extractant, makes the copper in the micro-etching solution be transferred to organic phase; The mother liquor that stays after the extraction can be used as the raw material that micro-etching solution recycles, and the copper in the organic phase is recyclable after back extraction.
Film-electrodip process wherein is a kind of technology (device) that membrane sepn process and electrochemical process are combined, employed film is a kind of spacer that solution can be isolated but can allow ion pass through, and galvanic deposit adopts direct current to make target product that chemical reaction take place on the anode or on the negative electrode exactly; The copper micro-etching solution can be placed on the positive column of film-electric deposition device, and the cupric ion in the solution can migrate to the cathodic area and separate out at negative electrode from the positive column at this moment; The copper micro-etching solution also can be delivered to the cathodic area this moment of the cupric ion in the solution of film-electric deposition device and can directly separate out on negative electrode, and dual mode has all been realized the selective copper separation.Said film is selected from ceramic membrane, asbestos diaphragm and organic high molecular layer, and organic high molecular layer comprises anion-exchange membrane and cationic exchange membrane.
Wherein the characteristics of the precipitator method are to add some can make the precipitated material that comes out of copper in micro-etching solution, as precipitation agent and reductive agent etc.Precipitation agent comprises and contains S
2-Or S
-Material, or contain sulfydryl (material SH), as ammonium sulfide, sulphur hydrogenation ammonium (NH
4HS), dithioglycol etc.Reductive agent be in can reducing solution monovalence copper or (with) cupric material, as sodium borohydride, hydrazine hydrate, hydrogen, formaldehyde etc.
For the precipitation process, film-electrodeposition process and the solvent extraction process that make separating copper from micro-etching solution is effective, can carry out necessary pre-treatment such as redox potential earlier to pending micro-etching solution and regulate, PH regulates, temperature regulation etc.
The selective separation copper process of micro-etching solution can be finished under the room temperature normal pressure, also can finish under other temperature and pressure.Generally speaking, behind selective separation copper, the copper concentration in the micro-etching solution is controlled in the desired scope of microetch process, as≤24g/L, make recycling of micro-etching solution become possibility.
By second aspect of the present invention, the peroxide concentrations in the micro-etching solution controlled have following feature:
The method of peroxide concentrations is electrochemistry online generation superoxide method or the method that adds superoxide (as hydrogen peroxide) in the said control micro-etching solution: add the superoxide method and promptly directly add superoxide (as hydrogen peroxide) in solution, so that the concentration of superoxide wherein meets the requirement of microetch, as (peroxide radical content) 〉=2.5g/L; The online generation superoxide of electrochemistry method is (both can be before having adjusted copper concentration with the solution of peroxide concentrations to be adjusted, also can be after adjusting copper concentration, also can carry out synchronously with the process of adjusting copper concentration) place the positive column of an electrolyzer as anolyte, select the suitable superoxide anode of analysing, the electrolysis regular hour in certain volts DS scope, certain temperature range and certain current density scope, wherein peroxide concentrations is returned in the scope that microetch requires.The electrolyzer of being learned can be that common electrolyzer also can be the electrolyzer that the film spacer is arranged; Wherein said film (spacer) can be selected from ceramic membrane, asbestos diaphragm and organic high molecular layer, and organic high molecular layer comprises anion-exchange membrane and cationic exchange membrane.The superoxide anode of analysing that said electrolyzer uses can be lead anode or graphite anode or platinum anode, also can be the insoluble titanium anode (DSA) etc. that coating of metal oxides such as platinum ruthenium iridium is arranged, and negative electrode can be titanium plate or steel plate etc. not.The selective separation copper process of copper micro-etching solution can be finished under the room temperature normal pressure, also can finish under other temperature and pressure.
After the above-mentioned selective separation copper of process is the adjusting of effective control of copper concentration and peroxide concentrations, copper concentration in the micro-etching solution and peroxide concentrations just can satisfy the requirement of microetch process, making it continue to use or using for a long time becomes possibility, stops or reduced significantly the Liquid wastes discharging of microetch operation.
Embodiment 1:
A kind of Sodium Persulfate type micro-etching solution that the PCB industry is used, when normally using its microetch speed as the 1-7 micron/minute, the microetch process generally controls its copper content and Sodium Persulfate concentration is respectively: copper≤24g/L, 20-80g/L (in Sodium Persulfate).Its microetch speed is 0.15 micron/minute when scrapping, and the concentration of its copper and Sodium Persulfate is respectively after measured: copper 32.5g/L, Sodium Persulfate 6.5g/L; Get 1 liter of this useless micro-etching solution, placing cumulative volume is that 2 liters of (each 1 liter of yin, yang polar region), membrane areas are 450cm
2The positive column (film is the Nafion ion-exchange membrane of Du Pont company) of film-electrolyzer, it is sulfuric acid-ammoniumsulphate soln of 1-5 that pH is placed in the cathodic area, anode adopts titanium base insoluble anode (DSA), negative electrode adopts stainless steel plate, the temperature of maintenance system is at 20-65 ℃, pressing 2.1-5.1 volt and electric current at groove is under the condition of 0.5-2 (peace) electrolysis 15-20 hour, the copper concentration that records positive column solution becomes 10.5 grams per liters, and Sodium Persulfate concentration becomes 45.3g/L (in Sodium Persulfate), and cathodic area output copper 22 grams; With above-mentioned anolyte after having passed through the control of copper concentration and peroxide concentrations and regulating again as micro-etching solution also with relevant component (as the halogen ion, copper inhibitor etc.) be adjusted to the normal range that microetch requires after, record its microetch speed and be copper the 2-5 micron/minute, meet the requirement of microetch process.
Embodiment 2:
A kind of ammonium persulphate type micro-etching solution that the PCB industry is used, when normally using its microetch speed as the 1-7 micron/minute, the microetch process generally controls its copper content and Sodium Persulfate concentration is respectively: copper≤24g/L, 25-85g/L (in ammonium persulphate).Its microetch speed is 0.23 micron/minute when scrapping, and the concentration of its copper and ammonium persulphate is respectively after measured: copper 31.5g/L, ammonium persulphate 5.3g/L; Get 1 liter of this useless micro-etching solution, placing cumulative volume is that 2 liters of (each 1 liter of yin, yang polar region), membrane areas are 450cm
2The positive column (film is the JCM cationic membrane that the global profit in Beijing reaches environmental protection company) of film-electrolyzer, it is sulfuric acid-ammoniumsulphate soln of 1-5 that pH is placed in the cathodic area, anode adopts titanium base insoluble anode (DSA), negative electrode adopts stainless steel plate, the temperature of maintenance system is at 30-60 ℃, pressing 2.3-5.2 volt and electric current at groove is under the condition of 0.75-1.5A (peace) electrolysis 20-24 hour, the copper concentration that records positive column solution is 12.5 grams per liters, and ammonium persulphate concentration becomes 50.2g/L (in ammonium persulphate), and cathodic area output copper 19 grams; With above-mentioned anolyte after having passed through the control of copper concentration and peroxide concentrations and regulating again as micro-etching solution also with relevant component (as the halogen ion, copper inhibitor etc.) be adjusted to the normal range that microetch requires after, record its microetch speed and be copper the 3-6 micron/minute, meet the requirement of microetch process.
Claims (7)
1. the present invention relates to the control method of a kind of micro-etching solution peroxide concentrations, copper concentration and the application in it recycles, it is characterized in that:
(1) micro-etching solution is the peroxide type micro-etching solution, and the industry of using of its first-selection is industry of printed circuit boards.
(2) span of control of the copper concentration in the micro-etching solution is: copper≤40g/L.
(3) the concentration span of control of superoxide is in the micro-etching solution: peroxide root (O-O-) content 1-10g/L.
(4) purpose that superoxide and copper concentration are regulated and control is to realize recycling of micro-etching solution.
2. according to the method for claim 1, it is characterized in that: said microetch is a kind of surface treatment work area, its uses micro-etching solution to dissolve part material on the pending workpiece surface, its objective is the surface coarsening that makes pending workpiece and increases sticking power between itself and the exotic; Its technical characterictic is only faint corrosion (as depth of corrosion 0.1-3.5 micron) rather than degree of depth corrosion (as 8-15 micrometer depth or more corrosion etc.) to be carried out in the surface of processed workpiece, more is not whole dissolvings.The peroxide type micro-etching solution that the present invention is directed to is characterized in containing superoxide, and superoxide is to contain peroxide bridge (compound O-O-) such as hydrogen peroxide, persulfuric acid and salt thereof, peroxycarboxylic acid and salt thereof, permonosulphuric acid and salt thereof etc.
3. according to the method for claim 1 and 2, it is characterized in that: the span of control of the copper concentration in the micro-etching solution is: copper≤40g/L, preferable range is copper≤24g/L.The method of copper concentration is following selective separation copper method in the said control micro-etching solution: or solvent extration, or film-electrodip process, or the precipitator method; Or the arbitrary combination of these three kinds of methods.
4. according to the method for claim 1,2 and 3, it is characterized in that: the scope of peroxide concentrations is in the said control micro-etching solution: peroxide radical content 1-10g/L, preferable range is peroxide radical content: 2.5-6g/L.The method of peroxide concentrations is the method for the online generation superoxide of electrochemistry or the method that adds superoxide in the control micro-etching solution; The method that wherein adds superoxide promptly directly adds superoxide in solution, so that the concentration of superoxide wherein meets the requirement of microetch, as make peroxide radical content 〉=2.5g/L; The method of the online generation superoxide of electrochemistry is the positive column that the micro-etching solution of peroxide concentrations to be adjusted is placed an electrolyzer as anolyte, select the suitable superoxide anode of analysing, the electrolysis regular hour in certain volts DS scope, certain PH scope, certain temperature range and certain current density scope, wherein peroxide concentrations is returned in the scope that microetch requires; As make peroxide radical content 〉=2.5g/L.
5. according to claim 1,2,3 and 4 method, it is characterized in that: on order of operation, the process of said control micro-etching solution peroxide concentrations both can be before the copper concentration of regulation and control micro-etching solution, also can after the copper concentration of regulation and control micro-etching solution, also can carry out synchronously with the process of regulation and control micro-etching solution copper concentration.
6. according to claim 1,2,3,4 and 5 method, it is characterized in that: originally owing to copper ion concentration too high and (or) the peroxide concentrations underproof micro-etching solution of microetch index (promptly so-called give up micro-etching solution) that causes on the low side, after through above-mentioned copper concentration control and peroxide concentrations adjusting, can use as micro-etching solution again.
7. according to claim 1,2,3,4,5 and 6 method, it is characterized in that: the solvent extration in the said selective separation copper method is conventional phase disengagement method, be about to pending micro-etching solution and contact, make the copper in the micro-etching solution be transferred to organic phase with the organic phase that contains copper extractant; The mother liquor that stays after the extraction can be used as the raw material that micro-etching solution recycles, and the copper in the organic phase is recyclable after back extraction.Film-electrodip process in the said selective separation copper method is a kind of copper separation method that membrane sepn process and electrochemical process are combined, its use can allow ion by but can carry out isolated film and under the effect of DC electric field, realize the directional migration of cupric ion and recovery on negative electrode solution--be that copper separates from micro-etching solution; The optional ceramic membrane of said film, asbestos diaphragm and ion-exchange membrane, first-selected ion-exchange membrane.The precipitator method in the said selective separation copper method are to add some can make the precipitated material that comes out of copper in micro-etching solution, as precipitation agent and reductive agent etc.Generally speaking, behind selective separation copper, the copper concentration in the micro-etching solution is controlled in the desired scope of microetch process, makes recycling of micro-etching solution become possibility.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510031481 CN1854342A (en) | 2005-04-26 | 2005-04-26 | Method for controlling concentration of peroxide and copper in microetching liquid and its circulative usage |
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|---|---|---|---|
| CN 200510031481 CN1854342A (en) | 2005-04-26 | 2005-04-26 | Method for controlling concentration of peroxide and copper in microetching liquid and its circulative usage |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101833341A (en) * | 2010-05-19 | 2010-09-15 | 四川超声印制板有限公司 | Automatic control system of PH value in alkaline etching and control method thereof |
| CN101935838A (en) * | 2010-08-01 | 2011-01-05 | 梅州博敏电子有限公司 | Microetching processing method used before copper deposition of printed circuit board |
| CN101988200A (en) * | 2009-08-04 | 2011-03-23 | 章晓冬 | Cyclic regeneration and metal reclamation equipment for acid chloride-containing etchant |
| CN102833963A (en) * | 2012-09-03 | 2012-12-19 | 高德（无锡）电子有限公司 | Horizontal pre-treatment method for improving copper exposing at bottom of blind drilling hole in soft gold electroplating |
| CN103952705A (en) * | 2014-05-19 | 2014-07-30 | 广州市太和电路板有限公司 | Online regeneration method and device of micro-etching liquid |
| CN107022762A (en) * | 2017-05-08 | 2017-08-08 | 广东光华科技股份有限公司 | The application of three amido fortified phenols or three amido substituted benzene thiophenols and tiny-etching treatment fluid |
-
2005
- 2005-04-26 CN CN 200510031481 patent/CN1854342A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101988200A (en) * | 2009-08-04 | 2011-03-23 | 章晓冬 | Cyclic regeneration and metal reclamation equipment for acid chloride-containing etchant |
| CN101833341A (en) * | 2010-05-19 | 2010-09-15 | 四川超声印制板有限公司 | Automatic control system of PH value in alkaline etching and control method thereof |
| CN101833341B (en) * | 2010-05-19 | 2012-02-22 | 四川超声印制板有限公司 | Automatic control system of PH value in alkaline etching and control method thereof |
| CN101935838A (en) * | 2010-08-01 | 2011-01-05 | 梅州博敏电子有限公司 | Microetching processing method used before copper deposition of printed circuit board |
| CN102833963A (en) * | 2012-09-03 | 2012-12-19 | 高德（无锡）电子有限公司 | Horizontal pre-treatment method for improving copper exposing at bottom of blind drilling hole in soft gold electroplating |
| CN102833963B (en) * | 2012-09-03 | 2015-04-01 | 高德（无锡）电子有限公司 | Horizontal pre-treatment method for improving copper exposing at bottom of blind drilling hole in soft gold electroplating |
| CN103952705A (en) * | 2014-05-19 | 2014-07-30 | 广州市太和电路板有限公司 | Online regeneration method and device of micro-etching liquid |
| CN103952705B (en) * | 2014-05-19 | 2016-02-24 | 广州市太和电路板有限公司 | A kind of method of micro-etching solution on-line regeneration and device |
| CN107022762A (en) * | 2017-05-08 | 2017-08-08 | 广东光华科技股份有限公司 | The application of three amido fortified phenols or three amido substituted benzene thiophenols and tiny-etching treatment fluid |
| CN107022762B (en) * | 2017-05-08 | 2019-07-30 | 广东光华科技股份有限公司 | The application of three amido fortified phenols or three amido substituted benzene thiophenols and tiny-etching treatment fluid |
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