Detection method and detection device for copper-coated particles

Abstract

The embodiment of the invention relates to the field of material detection, and provides a detection method and a detection device for copper-coated particles, and the method comprises the following steps: placing the copper-coated particles subjected to heat treatment in an acid solution with the pH value of 4-6; the color of the acid solution is collected every other time period, if the color of the acid solution is lighter than the standard color in the preset time period, it is determined that the compactness of the copper-coated particles meets the standard, and if the color of the acid solution is darker than the standard color in the preset time period, it is determined that the copper-coated particles have the compactness defect. The preset time period and the pH value of the acid solution have a preset relationship, and the preset time period comprises a plurality of time periods. According to the detection method of the copper-clad particles, provided by the embodiment of the invention, at least the problem that the detection period of the metal copper-clad slurry is relatively long can be improved.

Description

Technical Field

[0001] This application relates to the field of materials testing, and in particular to a method and apparatus for detecting copper-clad particles. Background Technology

[0002] Solar cells have high requirements for the quality of metal powder coating in copper-clad metal paste. Copper-clad particles, as a low-cost, high-conductivity metal powder, are widely used in the low-temperature conductive paste of solar cells. However, traditional methods for detecting the density and encapsulation of metal powder in copper-clad metal paste generally suffer from problems such as long detection cycles, complex operations, high equipment dependence, or stringent conditions. These methods are difficult to meet the quality monitoring needs of copper-clad metal paste in the large-scale production of high-efficiency cells, which require rapid, intuitive, low-cost, and online-applicable quality control. Summary of the Invention

[0003] This application provides a method and apparatus for detecting copper-clad particles, which at least helps to improve the problem of long detection cycles for copper-clad metal pastes in the prior art.

[0004] According to some embodiments of this application, one aspect of this application provides a method for detecting copper-clad particles, comprising: placing the heat-treated copper-clad particles in an acidic solution, wherein the pH value of the acidic solution is 4-6; collecting the color of the acidic solution at regular intervals; if the color of the acidic solution is lighter than the standard color within a preset time interval, it is determined that the density of the copper-clad particles meets the standard; if the color of the acidic solution is darker than the standard color within the preset time interval, it is determined that the copper-clad particles have the density defect; wherein the preset time interval has a preset relationship with the pH value of the acidic solution, and the preset time interval includes multiple time intervals.

[0005] In some embodiments, the solute in the acidic solution includes at least one of the following: organic acids and inorganic acids.

[0006] In some embodiments, the molar ratio of the organic acid to the inorganic acid is 1:9 to 9:1.

[0007] In some embodiments, the organic acid includes at least one of the following: glacial acetic acid, citric acid, and tartaric acid.

[0008] In some embodiments, the inorganic acid includes at least one of the following: hydrochloric acid, phosphoric acid, sulfuric acid, and nitric acid.

[0009] In some embodiments, when the acidic solution is the organic acid, the temperature of the acidic solution is 60~95°C.

[0010] In some embodiments, when the solute in the acidic solution is glacial acetic acid, the concentration of glacial acetic acid is 99.5-100%.

[0011] In some embodiments, the detection method further includes: comparing the color of the solution after the copper-clad particles and the acidic solution react with a standard color chart, wherein the standard color chart includes at least one of the following: Pantone color chart, LAUTER color chart, and national standard industrial color chart.

[0012] In some embodiments, the preset time period is 2 to 10 minutes.

[0013] In some embodiments, the temperature of the heat treatment is 200~300℃ and the time is 1~20min.

[0014] According to some embodiments of this application, another aspect of this application provides a detection device for copper-clad particles, comprising: a placement module for placing heat-treated copper-clad particles in an acidic solution, the pH value of the acidic solution being 4-6; and a collection module for collecting the color of the acidic solution at regular intervals. If the color of the acidic solution is lighter than a standard color within a preset time interval, the density of the copper-clad particles is determined to meet the standard. If the color of the acidic solution is darker than the standard color within the preset time interval, the copper-clad particles are determined to have a density defect. The preset time interval has a preset relationship with the pH value of the acidic solution, and the preset time interval includes multiple time intervals.

[0015] The technical solution provided in this application has at least the following advantages:

[0016] The detection method for copper-clad particles in this application first places the copper-clad particles in an acidic solution with a pH of 4-6. The color of the acidic solution is collected at preset time intervals. If the color of the acidic solution is lighter than the standard color within a preset time period, the density of the copper-clad particles is determined to meet the standard; if the color of the acidic solution is darker than the standard color within a preset time period, the copper-clad particles are determined to have a density defect. By using an acidic solution with a pH of 4-6 under mild conditions to rapidly develop a color reaction in the copper-clad paste, and comparing the collected color with the standard color, a lighter color indicates less copper dissolution and a denser coating layer, while a darker color indicates the opposite. This allows for rapid qualitative assessment of the density of the silver coating layer based on the degree of color development, solving the problems of complex operation and long time consumption in traditional methods. It meets the need for rapid screening of paste quality in high-efficiency solar cell production lines, and further solves the problem of long detection cycles for copper-clad pastes in existing technologies. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of a method for detecting copper-clad particles according to an embodiment of this application;

[0019] Figure 2 This is a schematic diagram of a detection device for copper-clad particles proposed in an embodiment of this application. Detailed Implementation

[0020] As can be seen from the background technology, traditional methods for detecting the density and encapsulation of metal powder in metal-coated copper paste generally suffer from problems such as long detection cycles, complex operations, high equipment dependence, or stringent conditions, making it difficult to meet the quality monitoring needs of metal-coated copper paste in the large-scale production of high-efficiency batteries, which require fast, intuitive, low-cost, and online-applicable production lines.

[0021] This application provides a method and apparatus for detecting copper-clad particles. The method includes: placing the heat-treated copper-clad particles in an acidic solution with a pH of 4-6; collecting the color of the acidic solution at regular intervals; if the color of the acidic solution is lighter than the standard color within a preset time period, the density of the copper-clad particles is determined to meet the standard; if the color of the acidic solution is darker than the standard color within a preset time period, the copper-clad particles are determined to have a density defect. The preset time period has a preset relationship with the pH value of the acidic solution, and the preset time period includes multiple time periods.

[0022] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0024] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0025] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0026] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0027] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0028] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0029] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0030] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the word "part" is also intended to include the plural form, unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0031] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0032] According to one embodiment of this application, such as Figure 1 As shown, a method for detecting copper-clad particles is proposed, including:

[0033] Step S1: Place the heat-treated copper-clad particles in an acidic solution with a pH of 4 to 6.

[0034] Optionally, heat treatment can promote or accelerate the deterioration of the density of the copper coating layer, thus allowing for faster detection results. The amount of copper-clad particles can be 1-3g. The reaction environment should be kept weakly acidic throughout the reaction. This can be achieved by using a weak acid directly, or by diluting a strong acid to obtain a solution with a pH of 4-6. The acidic solute used to form the acidic solution can be selected appropriately based on the specific detection environment. Within this pH range, the hydrogen ion concentration in the solution is sufficient to provide a certain degree of corrosion driving force, but not enough to trigger a violent chemical reaction or non-selectively dissolve the copper-clad particles. Since the structure of the copper-clad particles depends on the physical coating of the internal copper core by the external silver layer, this weakly acidic condition can selectively act on areas with defects in the silver layer, causing the exposed copper to react with hydrogen ions, while the dense and intact silver layer can still effectively block the penetration of the acidic solution. Limiting the pH value restricts the intensity and selectivity of the reaction, ensuring that the detection process only responds to areas of incomplete coating. This avoids the silver layer being eroded due to excessive acidity or having no visible reaction due to insufficient acidity, thus providing a controllable and repeatable chemical environment basis for determining coating integrity. The copper-clad particles (metal-coated copper particles) can be tin-coated copper particles, nickel-coated copper particles, or silver-coated copper particles; this application does not specify a particular type.

[0035] Step S2: At regular intervals, the color of the acidic solution is collected. If the color of the acidic solution is lighter than the standard color within a preset time period, it is determined that the density of the copper-clad particles meets the standard. If the color of the acidic solution is darker than the standard color within a preset time period, it is determined that the copper-clad particles have a density defect. The preset time period has a preset relationship with the pH value of the acidic solution. The preset time period includes multiple time periods.

[0036] Optionally, the preset time period can be 2 to 10 minutes, or a shorter period within this range, such as 20 seconds or 30 seconds. This preset time period is sufficient to observe whether the copper-clad particles have a density problem. Collecting the color of the acidic solution at regular intervals means observing and recording the visual color state of the liquid in the reaction system at fixed time intervals to obtain dynamic information on color changes. If the color of the acidic solution is lighter than the standard color within the preset time period, the density of the copper-clad particles is determined to meet the standard, indicating that the observed color has not reached the preset reference threshold, reflecting that the amount of copper ion dissolution is lower than the level corresponding to the standard. If the color of the acidic solution is darker than the standard color within the preset time period, the copper-clad particles are determined to have a density defect, indicating that the observed color exceeds the preset reference threshold, reflecting that the amount of copper ion dissolution is higher than the level corresponding to the standard. Thus, a qualitative judgment on the integrity of the silver coating layer is achieved through direct comparison of color depth.

[0037] The detection method described in this application uses an acidic solution with a pH of 4-6 to rapidly develop a colorimetric reaction in the copper-coated metal paste under mild conditions. The collected color is compared with a standard color. The lighter the color, the less copper is dissolved and the denser the coating layer, and vice versa. This allows for a rapid qualitative assessment of the density of the silver coating layer based on the degree of color development. This solves the problems of complex operation and long time consumption in traditional methods, meets the needs of high-efficiency solar cell production lines for rapid screening of paste quality, and solves the problem of long detection cycles for copper-coated metal pastes in the prior art.

[0038] In some optional embodiments, the heat treatment temperature is 200~300℃ and the time is 1~20min. Before inspecting the copper-clad particles, the copper-clad particles can be heat-treated first. Setting the heat treatment temperature and time to the above range can gently reduce the density of the outer coating of the copper-clad particles, which is equivalent to amplifying the defects. This can magnify the inspection results, making the inspection results more intuitive and accurate.

[0039] In addition to the method of detecting through pH value mentioned above, the mass of copper-plated particles before and after the reaction can also be used to determine the result.

[0040] The copper-coated particles before the reaction are placed on an electronic balance to obtain their initial value. The electronic balance can be a high-sensitivity analytical balance with an accuracy of ±0.1 mg. A glacial acetic acid solution (concentration ≥99.7%) is used. This solution reacts with copper oxide (copper oxide formed when exposed copper reacts with oxygen) to produce copper acetate and water (under heating conditions: 4CH3COOH + 2Cu + O2 → 2Cu(CH3COO)2 + 2H2O). After the reaction, the copper-coated particles are separated from the glacial acetic acid solution, and the particles are weighed to obtain the final value. The difference between the final and initial values ​​indicates copper loss, thus determining whether the density of the copper-coated particles meets the requirements. If the mass loss is within a preset range, the density is preliminarily determined to be acceptable; if it is outside the preset range, the density is deemed unacceptable. Combining the pH value detection method with the mass difference before and after the reaction can further refine the results. The preset range can be selected based on actual conditions.

[0041] The above reaction principle can also be improved by adding hydrogen peroxide solution to the reaction solution. This can accelerate the reaction rate of the first stage, allowing the exposed copper to fully react and form copper oxide, thus making the reaction result more accurate (2CH3COOH+Cu+H2O2→2Cu(CH3COO)2+2H2O).

[0042] In the above embodiments, the range of the difference between the final and initial values ​​of the copper-clad particles reflects the barrier effect of the copper-clad particle coating on the internal copper core. A well-dense coating inhibits the reaction between oxygen and copper, thereby reducing the reaction between acid and copper oxide. Conversely, a lack of density leads to an intensified reaction, resulting in more copper oxide being generated and more copper ions being displaced. This range of the difference between the final and initial values ​​of the copper-clad particles, along with color interpretation, forms a dual verification mechanism. This effectively avoids subjective errors caused by differences in illumination, visual misjudgment, uneven sample dispersion, or fluctuations in local reaction intensity. It improves the objectivity, stability, and anti-interference ability of the density assessment, thereby achieving a more accurate and reliable quantitative determination of the coating quality of the copper-clad particles.

[0043] In some optional embodiments, the solute in the acidic solution includes at least one of the following: organic acid and inorganic acid. The copper-clad particles are placed in an acidic solution with a pH of 4-6, and the solute in this acidic solution can be an organic acid, an inorganic acid, or a mixture of organic and inorganic acids. The acidic solution of this application can use a variety of acids as the solute, making the detection method more practical and applicable to a wider range of scenarios.

[0044] If the acidic solution is a mixed acid, in some optional embodiments, the molar ratio of organic acid to inorganic acid is 1:9 to 9:1. The organic acid content can be 10% to 90%, for example, 20%, 30%, 40%, 50%, 60%, 70%, and 80%, with a range of 20% to 30%, 30% to 70%, and 80% to 90%. The inorganic acid content can also be 10% to 90%, for example, 20%, 30%, 40%, 50%, 60%, 70%, and 80%, with a range of 20% to 30%, 30% to 70%, and 80% to 90%. The inorganic acid in the mixed acid can regulate the reaction rate, and the organic acid can inhibit corrosion of the coating layer, thus producing a synergistic effect.

[0045] In some optional embodiments, the organic acid includes at least one of the following: glacial acetic acid, citric acid, and tartaric acid. When the acidic solution is a mixture of inorganic and organic acids, the organic acid dominates the selective colorimetric reaction. The inorganic acid acts as a "buffer stabilizer" to regulate the pH of the system, suppressing pH fluctuations caused by the volatilization of some organic acids or the introduction of moisture into the sample. The organic acid can be at least one of glacial acetic acid, citric acid, and tartaric acid. Combined with an environmental condition of pH 4-6, the acidic solution maintains moderate corrosiveness while allowing for a mild reaction. This results in rapid detection without easily damaging the coating layer, generating a characteristic blue-green copper salt colorimetric reaction. The presence of the organic acid effectively suppresses excessive oxidation or color interference that may be caused by the inorganic acid, thereby achieving a stable and rapid colorimetric response to defects in the density of the coating layer. When the acidic solution contains only organic acids, this allows for a gentler reaction on the copper-clad particles. The organic acids only slowly corrode the exposed copper, having almost no effect on the intact silver layer. This ensures that the detection response originates solely from coating defects, avoiding false positives. Furthermore, it lacks strong oxidizing properties and metal precipitation interference, resulting in stable color development (copper acetate blue is easily identifiable), and is non-toxic, readily biodegradable, and has extremely low wastewater treatment costs. The accuracy of the detection results is improved through the synergistic judgment of color depth and preset time periods.

[0046] In some optional embodiments, the inorganic acid includes at least one of the following: hydrochloric acid, phosphoric acid, sulfuric acid, and nitric acid. When the acidic solution is a mixture of inorganic and organic acids, wherein the inorganic acid may include at least one of hydrochloric acid, phosphoric acid, sulfuric acid, and nitric acid, the inorganic acid is diluted extensively and then mixed with the organic acid to achieve a pH of 4-6. This allows for the detection of the density of copper-clad particles, providing faster results without easily damaging the coating, and generating a characteristic blue-green copper salt color reaction. When the acidic solution is solely an inorganic acid, the chemical reaction occurs more rapidly, resulting in faster detection and significantly shortening the detection time. The acidic solute selectivity of this application is high, expanding the range of applicable scenarios and increasing the selectivity for materials.

[0047] In some optional embodiments, when the acidic solution is an organic acid, the temperature of the acidic solution is 60~95°C. The aforementioned temperature can be 70°C, 80°C, or 90°C, and the temperature range can be 60~70°C, 70~80°C, or 80~90°C. When the acidic solution is an organic acid (any one or more of glacial acetic acid, citric acid, and tartaric acid), by controlling the solution temperature within the range of 60~95°C, the reaction rate can be accelerated, allowing for a stable increase in the erosion rate of the copper substrate by the organic acid. This achieves controllability and repeatability of the color change response under pH conditions of 4~6. This temperature range effectively avoids the delay in judgment caused by slow reaction at low temperatures and the false positive signal caused by excessively rapid reaction at high temperatures, ensuring that the color changes collected within the preset time period can truly reflect the density differences of the silver coating layer, thereby improving the speed and reliability of the detection results, and ultimately achieving an accurate and intuitive assessment of the quality of the copper-clad particle coating layer.

[0048] In some alternative embodiments, when the solute in the acidic solution is glacial acetic acid, the concentration of the glacial acetic acid is 99.5% to 100%. The concentration can be 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, and 100%, with concentration ranges of 99.5% to 99.7%, 99.7% to 99.9%, and 99.9% to 100%. Using high-purity glacial acetic acid ensures that the reaction system has sufficient H₂. + Concentration and ability to dissolve exposed copper. When the solute in the acidic solution is glacial acetic acid, by limiting the concentration of glacial acetic acid to the above range, a stable and sufficient amount of H₂ is provided while maintaining a weakly acidic environment of pH 4-6. + The concentration of ions can effectively penetrate the microscopic defects in the copper-clad particle coating and selectively dissolve the exposed copper substrate, inducing quantifiable color changes. It can also avoid interference phenomena such as slow reaction and insensitive defect response due to too low acetic acid concentration, or non-specific corrosion of the silver layer and deepening of the solution background color due to too high concentration. This ensures a stable correspondence between color change and coating density, improves the sensitivity of the detection process, enhances the reliability of judgment, and ultimately achieves a rapid, intuitive, and accurate assessment of the coating quality of copper-clad particles.

[0049] In some optional implementations, the detection method further includes comparing the color of the solution after the copper-clad particles react with the acidic solution with a standard color chart, which includes at least one of the following: Pantone color chart, ROLAL color chart, and national standard industrial color chart. The copper-clad particles are placed in an acidic solution with a pH of 4-6 for reaction, and the color change of the solution is collected periodically within a preset time period. By visually comparing the actual color of the solution after the reaction with at least one legally recognized industrial standard color chart from the Pantone, ROLAL, or national standard industrial color charts, the original reliance on subjective judgment of "color depth" is transformed into an objective comparison with the standardized color chart. This eliminates inconsistencies in interpretation caused by individual visual differences, ensuring that the density assessment results have a unified judgment benchmark across different operators, batches, and testing environments. This achieves accurate and efficient identification of density defects in the copper-clad particle coating, improving the reliability and industrial applicability of the detection.

[0050] In some optional implementations, the preset time period is 2-10 minutes. The copper-clad particles are placed in an acidic solution with a pH of 4-6, and the color change of the solution is periodically collected within the 2-10 minute time window. By comparing the color intensity with a standard color, the density of the coating layer can be quickly determined. This time range and the pH value of the acidic solution form a synergistic constraint, ensuring sufficient reaction while compressing the traditional observation cycle of over 30 minutes to less than 10 minutes. This effectively avoids the problem of low detection efficiency caused by ambiguous time settings, achieving efficient, stable, and repeatable screening of copper-clad particle coating quality in a production line environment, significantly improving the speed and accuracy of quality control in the manufacturing process.

[0051] Another embodiment of this application provides a detection device for copper-clad particles, such as... Figure 2 As shown, it includes: a placement module 10, used to place the heat-treated copper-clad particles in an acidic solution with a pH value of 4-6; and a collection module 20, used to collect the color of the acidic solution at regular intervals. If the color of the acidic solution is lighter than the standard color within a preset time period, it is determined that the density of the copper-clad particles meets the standard. If the color of the acidic solution is darker than the standard color within a preset time period, it is determined that the copper-clad particles have a density defect. The preset time period has a preset relationship with the pH value of the acidic solution, and the preset time period includes multiple time periods.

[0052] By setting up a placement module to stably place the sample in an acidic solution with a pH value of 4-6, and combining this with a data acquisition module to periodically acquire solution color change data, and judging based on the correspondence between preset time periods and pH values, a systematic recording and comparison of the dynamic response process of coating density is achieved. Through standardized environmental control and periodic color acquisition, this device reduces human interpretation errors and improves the repeatability and traceability of test results. It is especially suitable for rapid screening of multiple batches of samples in production line environments. Compared with manual colorimetric methods, it enhances the objectivity and stability of the detection process, and supports automated matching with standard colorimetric sequences, providing engineering-feasible hardware support for online quality control of copper-clad particle coating quality.

[0053] This application, based on the core technical solution of "acetic acid heating and color development + simultaneous monitoring of the mass difference of copper-clad particles before and after the reaction," achieves a revolutionary speedup in the detection of copper-clad particle coating properties, reducing the time required from "several hours" to "within 2 minutes." Traditional methods, such as EDTA titration, require pretreatment, titration, and calculation, taking more than 60 minutes; the silver nitrate method requires waiting 20-40 minutes for color gradation; and the high-temperature oleic acid method requires heating at 300℃ for 20-40 minutes plus cooling, with a total time exceeding 60 minutes, and none of these methods can be linked online. In contrast, this solution only requires adding 1-3g of copper-clad particle sample to glacial acetic acid (or a mixture of inorganic and organic acids) at pH 4-6, heating at a constant temperature of 85℃, and automatically identifying the depth of the blue-green change in the solution within 5-10 minutes via an image system (compared with a standard color chart). Replacing the acidic solution with an inorganic acid can further shorten the detection time. Simultaneously, a high-precision electronic scale is used to collect and interpret the mass loss of copper-plated particles caused by the displacement of copper ions. These two indicators are collected and interpreted in parallel, which can significantly shorten the waiting time and make the judgment results more accurate. The entire process, from sample addition to outputting the "qualified / downgraded / unqualified" conclusion, takes ≤10 minutes, improving the testing efficiency by about 3 times.

[0054] The detection method for copper-clad particles described above in this application will be specifically described below with reference to specific embodiments and comparative examples.

[0055] Example 1

[0056] 3g of silver-coated copper particles, heated at 200℃ for 5min, were placed in 99.8% glacial acetic acid (acidic solution) at 80℃.

[0057] Every 30 seconds, the color of glacial acetic acid was collected and compared with the Pantone color chart.

[0058] Example 2

[0059] The difference from Example 1 is that the acidic solution is dilute sulfuric acid with a pH of 4.

[0060] Example 3

[0061] The difference from Example 1 is that the acidic solution is a mild solution of glacial acetic acid and dilute sulfuric acid, with a molar ratio of 1:1.

[0062] Example 4

[0063] The difference from Example 3 is that the molar ratio of glacial acetic acid to dilute sulfuric acid is 1:9.

[0064] Example 5

[0065] The difference from Example 3 is that the molar ratio of glacial acetic acid to dilute sulfuric acid is 9:1.

[0066] Comparative Example 1

[0067] The silver-coated copper powder was mixed with a ferric chloride solution with a concentration of 80g / 500mL to obtain a mixed solution. The mass ratio of ferric oxide to silver-coated copper powder was 1:3.

[0068] Take the supernatant of the mixed solution, add hydrochloric acid to settle it, make up the volume and add an indicator to obtain the test solution. The volume ratio of hydrochloric acid to supernatant is 1:1, and the indicator is 1-(2-pyridiniazo)-2-naphthol with a mass concentration of 0.9 g / L.

[0069] The test solution was titrated with a 0.05 mol / L disodium ethylenediaminetetraacetate titration solution, and the volume of the titration solution was recorded.

[0070] Comparative Example 2

[0071] Take 3g of silver-coated copper granules and place them in an acidic solution. The acidic solution used is 0.1mol / L silver nitrate solution.

[0072] Start timing from the moment the solution is added, observe and record the time it takes for the solution to turn deep blue.

[0073] 100g of silver-coated copper powder was selected and tested using the detection methods described in Examples 1-5 and Comparative Examples 1-2. The average data from the specific tests are shown in the table below:

[0074] Table 1

[0075]

[0076] As shown in Table 1, the detection time for Examples 1-5 is within 10 minutes. Specifically, the acidic solvent in Example 1 is milder; the acidic solvent in Example 2 reacts faster, significantly shortening the detection time; Examples 3-5 are mixed acids of organic and inorganic acids, with moderate detection times, allowing the detection time to be controlled within 10 minutes even with a relatively mild reaction. The detection method of this application effectively overcomes the limitation of traditional detection methods, which have a detection time exceeding 10 minutes, thus shortening the detection cycle.

[0077] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A method for detecting copper-clad particles, characterized in that, include: The heat-treated copper-clad particles are placed in an acidic solution with a pH of 4 to 6. The color of the acidic solution is collected at regular intervals. If the color of the acidic solution is lighter than the standard color within a preset time period, the density of the copper-clad particles is determined to meet the standard. If the color of the acidic solution is darker than the standard color within the preset time period, the copper-clad particles are determined to have a density defect. The preset time period has a preset relationship with the pH value of the acidic solution, and the preset time period includes multiple time periods.

2. The detection method according to claim 1, characterized in that, The solute in the acidic solution includes at least one of the following: organic acid and inorganic acid.

3. The detection method according to claim 2, characterized in that, The molar ratio of the organic acid to the inorganic acid is 1:9 to 9:

1.

4. The detection method according to claim 2, characterized in that, The organic acid includes at least one of the following: glacial acetic acid, citric acid, and tartaric acid.

5. The detection method according to claim 2, characterized in that, The inorganic acid includes at least one of the following: hydrochloric acid, phosphoric acid, sulfuric acid, and nitric acid.

6. The detection method according to claim 2, characterized in that, When the acidic solution is the organic acid, the temperature of the acidic solution is 60~95°C.

7. The detection method according to claim 4, characterized in that, When the solute in the acidic solution is glacial acetic acid, the concentration of glacial acetic acid is 99.5-100%.

8. The detection method according to claim 1, characterized in that, The detection method further includes: The color of the solution after the reaction of the copper-clad particles and the acidic solution is compared with a standard color chart, which includes at least one of the following: Pantone color chart, ROLAL color chart, and national standard industrial color chart.

9. The detection method according to claim 1, characterized in that, The preset time period is 2 to 10 minutes.

10. The detection method according to claim 1, characterized in that, The heat treatment is performed at a temperature of 200-300℃ for 1-20 minutes.

11. A detection device for copper-clad particles, characterized in that, include: A placement module is used to place the heat-treated copper-clad particles in an acidic solution with a pH value of 4 to 6. The data acquisition module is used to acquire the color of the acidic solution at regular intervals. If the color of the acidic solution is lighter than the standard color within a preset time period, it is determined that the density of the copper-clad particles meets the standard. If the color of the acidic solution is darker than the standard color within the preset time period, it is determined that the copper-clad particles have a density defect. The preset time period has a preset relationship with the pH value of the acidic solution, and the preset time period includes multiple time periods.

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