阅读说明：本技术 一种超细银粉色差的检测方法 (Method for detecting chromatic aberration of superfine silver powder ) 是由 袁帅 张圣欢 赵磊 郭翻坐 余明行 张宏亮 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种超细银粉色差的检测方法,向干净整洁、表面平整的PE自封袋中装入待测银粉或者向玻璃培养皿中装入待测银粉后将粉末压实,作为待测样,将标准超细银粉样品作为参照样,使用色差仪分别测定待测样和参照样,形成标准样品数据,记录色差仪的测量结果L,a,b以及ΔL,Δa,Δb,通过公式计算色差△E,若△E＜2判定待测银粉在合格范围内,若△E≥2则判定为待测银粉不合格；本发明在解决粉末态物料松散、表面不平造成的测试误差的问题上提供了有效解决手段,方法操作易行、方法重现性高,测试结果较为稳定。(The invention discloses a method for detecting chromatic aberration of superfine silver powder, which comprises the steps of filling silver powder to be detected into a PE self-sealing bag which is clean and tidy and has a flat surface or filling the silver powder to be detected into a glass culture dish, compacting the powder to be detected to be used as a sample to be detected, using a standard superfine silver powder sample as a reference sample, respectively measuring the sample to be detected and the reference sample by using a chromatic aberration meter to form standard sample data, recording measurement results L, a and b and delta L, delta a and delta b of the chromatic aberration meter, calculating the chromatic aberration delta E by a formula, judging that the silver powder to be detected is in a qualified range if the delta E is less than 2, and judging that the silver powder to be detected is unqualified if the delta E is more than or equal to 2; the invention provides an effective solution for solving the problem of test errors caused by loose powder materials and uneven surfaces, and the method has the advantages of easy operation, high reproducibility and stable test result.)

1. A method for detecting chromatic aberration of superfine silver powder is characterized by comprising the following steps: comprises the following steps

Filling silver powder to be detected into a clean, tidy and flat-surface PE self-sealing bag, and removing redundant air to flatly spread the silver powder in the bag; or, after the silver powder to be tested is filled into the glass culture dish, the powder is compacted, and the powder is flatly paved at the bottom of the culture dish; using the sample as a sample to be tested;

taking a standard superfine silver powder sample as a reference sample;

using a calibration white board as a calibration board to calibrate the color difference meter, then using the color difference meter to respectively measure a sample to be measured and a reference sample to form standard sample data, and recording measurement results L, a and b of the color difference meter;

the color difference Δ E is calculated by the following formula:

ΔE=[(ΔL)² + (Δa)² + (Δb)²]^1/2，

wherein, the delta L, the delta a and the delta b are the difference values of the sample to be tested and the reference sample;

and if the delta E is less than 2, judging that the silver powder to be detected is in the qualified range, and if the delta E is more than or equal to 2, judging that the silver powder to be detected is unqualified.

2. The method for detecting the chromatic aberration of the superfine silver powder according to claim 1, wherein the mass of the superfine silver powder filled in the PE self-sealing bag is 20.0-35.0 g.

3. The method for detecting the chromatic aberration of superfine silver powder according to claim 1, wherein the size of the glass culture dish is 35-75 mm.

Technical Field

The invention belongs to the technical field of material detection, and particularly relates to a method for detecting chromatic aberration of superfine silver powder.

Background

The superfine silver powder is used as one of important raw materials for preparing the conductive paste, and the batch stability of the superfine silver powder greatly influences the quality of a finished paste product.

The indexes commonly used for judging the quality of the superfine silver powder comprise chemical components, specific surface area, apparent density, tap density, particle size, micro morphology, chromatic aberration and the like.

The color difference is an index parameter which is more intuitive for judging the stability of the superfine silver powder batch. However, based on the particle state of the metal powder, no powder state color difference detection method exists in the industry at present, only by visual observation, and a few methods for preparing a wet sample are adopted for detection.

The methods are complicated to operate and long in time, or the results cannot be accurately judged, and the production quality is difficult to control well.

Disclosure of Invention

In view of the above, the present application provides a method for detecting chromatic aberration of ultrafine silver powder, which performs chromatic aberration test on the premise of eliminating interference of powder stacking density and powder flatness, thereby performing quality control.

In order to achieve the purpose, the technical scheme provided by the invention is a method for detecting the color difference of silver powder, which comprises the following steps:

step one, sample preparation: the invention provides two sample preparation methods;

taking the PE self-sealing bag as a sample container, filling silver powder to be detected into a clean, tidy and flat-surface No. 1 PE self-sealing bag, and removing redundant air to flatly spread the silver powder in the bag; or, taking the glass culture dish as a sample container, filling the silver powder to be detected into the glass culture dish, wherein the amount of the powder is ensured to be flatly paved at the bottom of the culture dish, and compacting the powder after filling so as to flatly pave the powder at the bottom of the culture dish; using the sample as a sample to be tested;

taking a standard superfine silver powder sample approved by both suppliers and demanders as a reference sample;

step two, calibration: using a calibration white board as a calibration board to calibrate the color difference meter;

step three, testing: respectively measuring a sample to be measured and a reference sample by using a color difference meter to form standard sample data, and recording measurement results L, a and b and difference values delta L, delta a and delta b of the sample to be measured and the reference sample;

fourthly, judging the result: the color difference meter is represented by the formula delta E = [ (delta L)² + (Δa)² + (Δb)²]^1/2Calculating delta E; the difference between the sample and the standard sample depends on the size of delta E, the difference between the sample and the standard sample is judged to be small when the delta E is less than 2, and the difference between the sample and the standard sample is large when the delta E is more than or equal to 2 in a qualified range, and the sample is judged to be unqualified.

Preferably, the mass of the superfine silver powder charged in the first step is 20.0-35.0 g.

Preferably, the size of the culture dish in the first step is 35-75 mm, and the bottom of the culture dish is not scratched in the processes of adding and flattening the metal powder and cleaning the culture dish, so that the result is not interfered.

The invention has the beneficial effects that: the invention provides two methods for preparing superfine silver powder samples, wherein the powder can form a smooth and compact light shielding layer in a PE bag or a culture dish, so that the test error caused by loose powder materials and uneven surface is avoided, the test accuracy and convenience are effectively improved, the influence of human factors on chromatic aberration is avoided, and a control means is provided for the batch quality of the superfine silver powder; meanwhile, the sample preparation method is simple and convenient to operate, the repeatability of the test result is good, the instrument is simple and easy to obtain, the judgment basis of the result is sufficient, and the method has popularization and application values.

The method provides an effective solution for solving the problem of test errors caused by loose powder materials and uneven surfaces, is easy to operate, has high reproducibility and stable test results, can provide a reliable quality control means for the stability of production batches of the superfine silver powder, and is suitable for large-scale industrial production.

Drawings

FIG. 1 is a diagram of a standard ultrafine silver powder sample prepared using a PE valve bag as a sample container;

FIG. 2 is a diagram of a sample of the ultrafine silver powder to be measured prepared using a glass petri dish as a sample container.

Detailed Description

The present invention will be further described with reference to the following specific examples.

Example 1

1) And filling the silver powder to be detected into the clean, tidy and smooth-surface No. 1 PE self-sealing bag, and removing redundant air to enable the powder to be flatly paved in the bag.

2) And using the calibration white board as a calibration board to calibrate the color difference meter.

3) And (3) taking a standard superfine silver powder sample approved by both suppliers and demanders as a reference sample, measuring by using a color difference meter to form standard sample data, then measuring the sample by using the color difference meter, and recording the measurement results L, a and b.

4) By the formula Δ E = [ (Δ L)² + (Δa)² + (Δb)²]^1/2And calculating delta E, judging that the delta E is in a qualified range when the delta E is less than 2, and judging that the delta E is not more than 2.

The reproducibility of the method, the specific sample loading and the data obtained are shown in the following table, tested by a number of tests:

according to the 12 groups of test results, the test method has high reproducibility and stability, and meanwhile, the color difference test results of different sample filling amounts during sample preparation are compared, so that the test result has the minimum deviation and the best repeatability when the filling amount is 30 g.

Example 2

1) And (3) filling silver powder to be detected into the glass culture dish, wherein the amount of the powder is ensured to be capable of being flatly paved at the bottom of the culture dish. After loading, the powder was compacted and spread evenly on the bottom of the petri dish.

2) And using the calibration white board as a color difference meter calibration board to calibrate the instrument.

3) And (3) taking a standard superfine silver powder sample approved by both suppliers and demanders as a reference sample, measuring by using a color difference meter to form standard sample data, then measuring the sample by using the color difference meter, and recording the measurement results L, a and b.

4) And calculating delta E, judging that the delta E is in a qualified range when the delta E is less than 2, and judging that the delta E is not more than 2.

The repeatability of the method was examined over multiple tests, and the specific dish size, sample loading and data obtained are shown in the following table:

according to the 9 groups of test results, the test method has high reproducibility and stability, and meanwhile, the results of the color difference test performed by culture dishes with different diameters in sample preparation are compared, so that the result deviation is small, and the repeatability is good. The larger the dish diameter, the larger the amount of sample required.

Example 3

1-1) filling silver powder to be detected into a glass culture dish with the diameter of 35mm, wherein the amount of the powder is ensured to be flatly paved at the bottom of the culture dish. After loading, the powder was compacted and spread evenly on the bottom of the petri dish. The preparation of 3 samples was repeated.

1-2) filling the silver powder to be measured into a glass culture dish with the diameter of 35mm, wherein the amount of the powder is ensured to be flatly paved at the bottom of the culture dish. After loading, the powder was not compacted and was allowed to lay loosely on the bottom of the petri dish. The preparation of 3 samples was repeated.

2) And using the calibration white board as a calibration board to calibrate the color difference meter.

3) And taking a standard superfine silver powder sample approved by both suppliers and demanders as a reference sample, measuring by using a color difference meter to form standard sample data, then measuring the sample by using the color difference meter, and recording four values of the measurement results L, a, b and delta E.

4) And calculating delta E, judging that the delta E is in a qualified range when the delta E is less than 2, and judging that the delta E is not more than 2.

The repeatability of the method was checked over multiple tests and the data obtained are shown in the following table:

as can be seen from the above 6 test results, the accumulation state and the flatness of the sample in the culture dish have a great influence on the repeatability of the result.

The embodiments are merely illustrative of the principles of the present invention and its efficacy, and it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept of the present invention, and these changes and modifications are within the scope of the present invention.