CN112420371A - Inductor preparation method - Google Patents
Inductor preparation method Download PDFInfo
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- CN112420371A CN112420371A CN202011164397.XA CN202011164397A CN112420371A CN 112420371 A CN112420371 A CN 112420371A CN 202011164397 A CN202011164397 A CN 202011164397A CN 112420371 A CN112420371 A CN 112420371A
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- amorphous nanocrystalline
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- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- 239000000843 powder Substances 0.000 claims abstract description 54
- 238000000034 method Methods 0.000 claims abstract description 24
- 238000000576 coating method Methods 0.000 claims abstract description 20
- 238000000137 annealing Methods 0.000 claims abstract description 16
- 239000011248 coating agent Substances 0.000 claims abstract description 13
- 238000009692 water atomization Methods 0.000 claims abstract description 5
- 238000000748 compression moulding Methods 0.000 claims abstract description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 18
- 238000010438 heat treatment Methods 0.000 claims description 15
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 13
- 229910017604 nitric acid Inorganic materials 0.000 claims description 13
- 238000002156 mixing Methods 0.000 claims description 10
- 238000002161 passivation Methods 0.000 claims description 7
- 238000003756 stirring Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 238000009413 insulation Methods 0.000 claims description 5
- 238000004321 preservation Methods 0.000 claims description 5
- 238000001132 ultrasonic dispersion Methods 0.000 claims description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000006247 magnetic powder Substances 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002159 nanocrystal Substances 0.000 description 2
- 239000002707 nanocrystalline material Substances 0.000 description 2
- 229920000647 polyepoxide Polymers 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 229910000976 Electrical steel Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910001004 magnetic alloy Inorganic materials 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229910000889 permalloy Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000009702 powder compression Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical group [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0206—Manufacturing of magnetic cores by mechanical means
- H01F41/0246—Manufacturing of magnetic circuits by moulding or by pressing powder
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Soft Magnetic Materials (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention provides a preparation method of an inductor, which comprises the following steps: s1, preparing spherical amorphous nanocrystalline powder by a water atomization preparation method; s2, carrying out pre-annealing treatment on the obtained amorphous nanocrystalline powder; s3, carrying out insulating coating treatment on the amorphous nanocrystalline powder after the pre-annealing treatment to obtain coated powder; and S4, performing compression molding and baking curing on the obtained coated powder to obtain the inductor. The inductor preparation method based on the pre-annealing treatment is applied, so that the inductor product prepared by the method has the characteristics of low loss and high magnetic conductivity.
Description
Technical Field
The invention relates to the technical field of soft magnetic alloy metallurgy, in particular to a preparation method of an inductor.
Background
The amorphous nanocrystalline material has high saturation magnetic induction, high magnetic conductivity, low coercive force, low high-frequency loss, good strong hardness, wear resistance, corrosion resistance, good temperature and environmental stability and the like, has excellent comprehensive performance, replaces permalloy, silicon steel and ferrite, is applied to the power electronic technology, shows the characteristics of small volume, high efficiency, energy conservation and the like, and has the optimal cost performance ratio in all metal soft magnetic materials.
The insulating coating is a key technology in the preparation process of the amorphous nanocrystalline product, the performance of the insulating coating layer is an important factor influencing the high-frequency loss of the magnetic powder core, and if the insulating coating layer is not completely or uniformly coated, the eddy current loss among the magnetic powder particles is sharply increased, so that the high-frequency loss of the magnetic powder core is increased.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a preparation method for an inductor.
The preparation method of the inductor comprises the following steps:
s1, preparing spherical amorphous nanocrystalline powder by a water atomization preparation method;
s2, carrying out pre-annealing treatment on the obtained amorphous nanocrystalline powder;
s3, carrying out insulating coating treatment on the amorphous nanocrystalline powder after the pre-annealing treatment to obtain coated powder;
and S4, performing compression molding and baking curing on the obtained coated powder to obtain the inductor.
Further, in step S2, the pre-annealing process includes continuously heating the amorphous nanocrystal powder at 400-500 ℃ for 50-80 min.
Further, in step S3, the insulating coating process uses a nitric acid solution as a passivation agent, and a uniform oxide film is formed on the surface of the amorphous nanocrystal powder by heating.
Further, in step S3, the insulation coating process includes the following steps:
s3-1, mixing the pre-annealed amorphous nanocrystalline powder with a nitric acid solution and an acetone solution, placing the obtained mixture in a closed container, heating in a water bath at constant temperature, and performing heat preservation treatment;
s3-2, fully reacting, and then opening the closed container until acetone is volatilized to obtain coated powder.
Further, in step S3-1, the heating temperature range of the constant temperature heating of the water bath is 55 to 80 ℃.
Further, in step S3-1, the heat preservation time is 25-40 min.
Further, in step S3-1, the mass ratio of the nitric acid solution to the amorphous nanocrystalline powder is 1.2-2.4 wt% during the mixing process.
Further, the mass ratio of the acetone solution to the amorphous nanocrystalline powder is 30-40 wt%.
Further, in step S3-2, the fully reacting process includes fully stirring the mixture in the closed container with a magnetic stirrer.
Further, in step S3-2, the fully reacting process includes outputting ultrasonic waves to the inside of the closed container, and subjecting the mixture to ultrasonic dispersion and mixing.
The invention has the beneficial effects that:
the inductor preparation method based on the pre-annealing treatment is applied, so that the inductor product prepared by the method has the characteristics of low loss and high magnetic conductivity.
By applying the coating method of the amorphous nanocrystalline powder, the amorphous nanocrystalline powder prepared by the method has good passivation effect, and the formed passivation film has the characteristic of regular and uniform coating; and the amorphous nanocrystalline powder obtained by coating has good insulation effect and higher voltage-resistant effect.
Drawings
FIG. 1 is a Xrd diagram of the amorphous nanocrystalline powder of the present invention after pre-annealing treatment;
FIG. 2 is a characteristic diagram of the amorphous nanocrystalline powder according to the present invention in a coating state after the insulating coating treatment;
FIG. 3 is a characteristic diagram of the coating state of amorphous nanocrystalline powder after phosphoric acid passivation insulation coating treatment in the prior art.
FIG. 4 is a graph of loss of an inductor integrally formed from different powders at 1 MHz.
Detailed Description
In order to make the technical solution, the purpose and the advantages of the present invention more apparent, the present invention will be further explained with reference to the accompanying drawings and embodiments.
The invention relates to a preparation method of an inductor, which comprises the following steps:
(1) the mother alloy is treated by a water atomization method to obtain spherical amorphous nanocrystalline powder.
(2) The amorphous nanocrystalline powder is subjected to pre-annealing treatment to eliminate cooling stress generated in the water atomization process.
(3) And carrying out insulating coating treatment on the amorphous nanocrystalline powder subjected to the pre-annealing treatment to obtain coated powder.
(4) And adding a binder into the coated powder to perform shaping treatment, and granulating by using a granulator to obtain shaped powder.
(5) Adding a lubricant into the obtained shaped powder, and stirring and mixing to obtain finished powder.
(6) And winding a coil and welding for forming, implanting the formed coil into a die, filling the formed coil with the finished product powder for pressing, and performing press forming to obtain an inductor blank.
(7) And baking and curing the inductor blank to obtain the finished inductor.
In the step (2), the pre-annealing temperature is controlled within-100 ℃ of the crystallization temperature to continue heating based on the limitation of the crystallization temperature. Taking 550 ℃ as an example of the crystallization temperature, the pre-annealing temperature is preferably 450 ℃ and the continuous heating time is preferably 60 min.
The following experimental data are listed for the pre-annealing treatment of the corresponding amorphous nanocrystalline powders:
in the step (3), an amorphous nanocrystalline powder coating method may be applied to the insulating coating process, and the method includes the following steps:
a1, mixing the obtained amorphous nanocrystalline powder with a nitric acid solution and an acetone solution, placing the obtained mixture in a closed container, heating in a water bath at constant temperature, and performing heat preservation treatment; the heating temperature of the constant-temperature heating of the water bath is preferably 60 ℃; the heat preservation treatment time is preferably 30 min.
A2, stirring the mixture in the closed container to make the mixture fully react; the stirring treatment mode can be selected to fully stir the mixture in the closed container by a magnetic stirrer or output the mixture in the closed container by ultrasonic waves so as to make the mixture subjected to ultrasonic dispersion mixing; a uniform oxide film is generated on the surface of the amorphous nanocrystalline powder based on the application of nitric acid solution as a passivating agent, and a coating powder is formed.
A3, after full reaction, opening the closed container to volatilize the acetone; and taking out the coated powder.
Wherein, as a preferred embodiment, the mass ratio of the nitric acid solution to the amorphous nanocrystalline powder is 1.2-2.4 wt% based on the mass of the amorphous nanocrystalline powder, and the nitric acid solution can be concentrated nitric acid with a concentration of 68%; the acetone solution accounts for 30-40 wt% of the amorphous nanocrystalline powder. No corresponding nitric acid reaction waste liquid is generated in the process, and no environmental pollution is caused.
The relevant performance data of the pressed inductance test ring prepared by insulating coating treatment of the corresponding amorphous nanocrystalline material are listed as verification reference: (pressed into rings 14X 8mm, pressure 600Mpa, 180 ℃ baking)
Obviously, the nitric acid passivation scheme has the advantages of higher dielectric strength and comparable permeability compared with the phosphoric acid passivation scheme.
The results of the pressed inductance test loop test with different concentrations are provided below:
in the step (4), the binder material is prepared by mixing organic silicon resin, epoxy resin and curing agent, and the mixture ratio is, in parts by mass, organic silicon resin: epoxy resin: the curing agent was 14.5:3: 1. The mass ratio of the binder material to the amorphous nanocrystalline powder is 1.0-5 wt%.
In the step (4), the lubricant is zinc stearate.
In the step (6), the pressure for press molding is controlled to be 500-800 MPa.
The following performance comparison conditions of the amorphous powder and crystalline powder compression ring test are provided:
the above description is only a preferred embodiment of the present invention, and those skilled in the art may still modify the described embodiment without departing from the implementation principle of the present invention, and the corresponding modifications should also be regarded as the protection scope of the present invention.
Claims (10)
1. The preparation method of the inductor is characterized by comprising the following steps of:
s1, preparing spherical amorphous nanocrystalline powder by a water atomization preparation method;
s2, carrying out pre-annealing treatment on the obtained amorphous nanocrystalline powder;
s3, carrying out insulating coating treatment on the amorphous nanocrystalline powder after the pre-annealing treatment to obtain coated powder;
and S4, performing compression molding and baking curing on the obtained coated powder to obtain the inductor.
2. The method for preparing an inductor according to claim 1, wherein in step S2, the pre-annealing process comprises continuously heating the amorphous nanocrystalline powder at 400-500 ℃ for 50-80 min.
3. The method for preparing an inductor according to claim 1, wherein in step S3, the insulation coating process uses a nitric acid solution as a passivation agent, and a uniform oxide film is formed on the surface of the amorphous nanocrystalline powder by heating.
4. The method for preparing an inductor according to claim 3, wherein in step S3, the insulation coating process comprises the steps of:
s3-1, mixing the pre-annealed amorphous nanocrystalline powder with a nitric acid solution and an acetone solution, placing the obtained mixture in a closed container, heating in a water bath at constant temperature, and performing heat preservation treatment;
s3-2, fully reacting, and then opening the closed container until acetone is volatilized to obtain coated powder.
5. The method for preparing the inductor according to claim 4, wherein in step S3-1, the heating temperature range of the water bath constant temperature heating is 55-80 ℃.
6. The method for preparing an inductor according to claim 5, wherein in step S3-1, the heat-preserving treatment time is 25-40 min.
7. The method for preparing an inductor according to claim 4, wherein in step S3-1, the mass ratio of the nitric acid solution to the amorphous nanocrystalline powder is 1.2-2.4 wt% in the mixing process.
8. The method for preparing an inductor according to claim 7, wherein the acetone solution accounts for 30-40 wt% of the amorphous nanocrystalline powder.
9. The method for preparing an inductor according to claim 4, wherein in step S3-2, the fully reacting process comprises fully stirring the mixture in the closed container with a magnetic stirrer.
10. The method for preparing an inductor according to claim 4, wherein in step S3-2, the fully reacting process comprises outputting ultrasonic waves to the inside of the closed container, and subjecting the mixture to ultrasonic dispersion mixing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011164397.XA CN112420371A (en) | 2020-10-27 | 2020-10-27 | Inductor preparation method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011164397.XA CN112420371A (en) | 2020-10-27 | 2020-10-27 | Inductor preparation method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102031511A (en) * | 2010-12-30 | 2011-04-27 | 合肥华清金属表面处理有限责任公司 | Surface processing agent for neodymium-iron-boron permanent magnet as well as preparation method and processing method thereof |
| CN102693798A (en) * | 2012-06-20 | 2012-09-26 | 浙江科达磁电有限公司 | Preparation method of high-performance nano-crystal magnetic powder core |
| CN103456480A (en) * | 2013-08-28 | 2013-12-18 | 黑龙江八一农垦大学 | One-step heat treatment preparation process method for soft nanocrystalline magnetic powder core |
| CN103594218A (en) * | 2013-09-13 | 2014-02-19 | 横店集团东磁股份有限公司 | Manufacturing method of high-superposition low-loss metal magnetic powder core |
| CN106229104A (en) * | 2016-08-31 | 2016-12-14 | 北京康普锡威科技有限公司 | A kind of soft magnetic composite powder and preparation process for magnetic powder core thereof |
| CN108666115A (en) * | 2018-05-08 | 2018-10-16 | 苏州世诺新材料科技有限公司 | A kind of low-loss amorphous, nanocrystalline magnetic sheet and preparation method thereof |
| CN109215924A (en) * | 2018-09-19 | 2019-01-15 | 鲁东大学 | A kind of in-situ passivation insulating wrapped processing method of metal soft magnetic composite material |
| CN109754979A (en) * | 2019-01-25 | 2019-05-14 | 同济大学 | A kind of multilayer coating structure soft-magnetic composite material and preparation method thereof |
-
2020
- 2020-10-27 CN CN202011164397.XA patent/CN112420371A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102031511A (en) * | 2010-12-30 | 2011-04-27 | 合肥华清金属表面处理有限责任公司 | Surface processing agent for neodymium-iron-boron permanent magnet as well as preparation method and processing method thereof |
| CN102693798A (en) * | 2012-06-20 | 2012-09-26 | 浙江科达磁电有限公司 | Preparation method of high-performance nano-crystal magnetic powder core |
| CN103456480A (en) * | 2013-08-28 | 2013-12-18 | 黑龙江八一农垦大学 | One-step heat treatment preparation process method for soft nanocrystalline magnetic powder core |
| CN103594218A (en) * | 2013-09-13 | 2014-02-19 | 横店集团东磁股份有限公司 | Manufacturing method of high-superposition low-loss metal magnetic powder core |
| CN106229104A (en) * | 2016-08-31 | 2016-12-14 | 北京康普锡威科技有限公司 | A kind of soft magnetic composite powder and preparation process for magnetic powder core thereof |
| CN108666115A (en) * | 2018-05-08 | 2018-10-16 | 苏州世诺新材料科技有限公司 | A kind of low-loss amorphous, nanocrystalline magnetic sheet and preparation method thereof |
| CN109215924A (en) * | 2018-09-19 | 2019-01-15 | 鲁东大学 | A kind of in-situ passivation insulating wrapped processing method of metal soft magnetic composite material |
| CN109754979A (en) * | 2019-01-25 | 2019-05-14 | 同济大学 | A kind of multilayer coating structure soft-magnetic composite material and preparation method thereof |
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