CN111063521A - Flame-retardant heat-conducting dry-type transformer encapsulating method - Google Patents
Flame-retardant heat-conducting dry-type transformer encapsulating method Download PDFInfo
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- CN111063521A CN111063521A CN201911389442.9A CN201911389442A CN111063521A CN 111063521 A CN111063521 A CN 111063521A CN 201911389442 A CN201911389442 A CN 201911389442A CN 111063521 A CN111063521 A CN 111063521A
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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
- H01F41/005—Impregnating or encapsulating
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K13/00—Use of mixtures of ingredients not covered by one single of the preceding main groups, each of these compounds being essential
- C08K13/04—Ingredients characterised by their shape and organic or inorganic ingredients
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/34—Silicon-containing compounds
- C08K3/36—Silica
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/49—Phosphorus-containing compounds
- C08K5/51—Phosphorus bound to oxygen
- C08K5/52—Phosphorus bound to oxygen only
- C08K5/521—Esters of phosphoric acids, e.g. of H3PO4
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K7/00—Use of ingredients characterised by shape
- C08K7/16—Solid spheres
- C08K7/18—Solid spheres inorganic
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/08—Cooling; Ventilating
- H01F27/22—Cooling by heat conduction through solid or powdered fillings
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2217—Oxides; Hydroxides of metals of magnesium
- C08K2003/2224—Magnesium hydroxide
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2227—Oxides; Hydroxides of metals of aluminium
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/02—Flame or fire retardant/resistant
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2203/00—Applications
- C08L2203/20—Applications use in electrical or conductive gadgets
- C08L2203/206—Applications use in electrical or conductive gadgets use in coating or encapsulating of electronic parts
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- Chemical & Material Sciences (AREA)
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- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Epoxy Resins (AREA)
Abstract
The invention discloses a flame-retardant heat-conducting dry-type transformer encapsulating method, which comprises the steps of encapsulating by adopting heat-conducting epoxy resin, wherein the heat-conducting epoxy resin comprises 100 parts by weight of liquid epoxy resin; 70-100 parts of a curing agent; 10-20 parts of a toughening agent; 0.1-0.7 part of an accelerator; 0.1-0.5 part of defoaming agent; 100 portions of alumina powder and 500 portions of alumina powder; then, carrying out secondary encapsulation by adopting flame-retardant epoxy resin, wherein the flame-retardant epoxy resin comprises 180 parts by weight of 100 parts of liquid epoxy resin; 70-100 parts of a curing agent; 5-10 parts of a toughening agent; 1-10 parts of a diluent; 1-10 parts of a flame retardant; 0.01-0.7 part of dispersant; 0.01-0.8 part of defoaming agent and 40-60 parts of alumina. The dry-type transformer manufactured by the invention has excellent flame retardance and heat conductivity, and the overall performance of the encapsulated dry-type transformer can be improved.
Description
Technical Field
The invention relates to the technical field of dry-type transformer encapsulation, in particular to a flame-retardant heat-conducting dry-type transformer encapsulation method.
Background
Dry transformers have found widespread use in electrical power systems. Because it has simple structure, maintains characteristics such as convenient, long-lived, high reliability, high fire-retardant, makes the work load of maintaining and overhauing in the operation reduce greatly, but the mountable is in the load center again simultaneously, receives more and more attention and promotes.
The epoxy resin dry-type transformer is clean and environment-friendly electric equipment, mainly uses epoxy resin as an insulating material, and the epoxy resin has been verified to have a reliable solid insulating material for more than 40 years. The dry type transformer poured by epoxy resin is valued and popularized due to the characteristics of no maintenance, high reliability, no pollution, recyclable use after the service life is over, and the like, and is widely applied to the fields of industrial and mining enterprises, power stations, airports, subways, ocean drilling platforms, and the like.
Epoxy resin dry-type transformers are generally installed and used indoors, and because of the danger of fire, the hidden danger of fire is increased. On the one hand, dry-type transformer surfaces, such as those in contact with external fire sources, may be ignited. On the other hand, the dry-type transformer in live operation is a latent fire itself and may ignite. Common causes of ignition are: the abnormal temperature rise of the dry type transformer causes local or overall overheating, external or internal short circuit, and electric sparks and arcs generated by insulation breakdown. In order to prevent the accident, when designing the dry type transformer and selecting the insulating material thereof, it should be considered to reduce the risk of fire of the dry type transformer.
With the rapid development of economic construction in China, the urban and rural electric load is continuously increased. The safe operation and service life of a dry-type transformer depends to a large extent on the safety and reliability of the insulation of the transformer windings. The resin insulation dry type transformer adopts epoxy resin as an insulation medium, and compared with an oil immersed transformer, the insulation performance and the heat resistance of the resin insulation dry type transformer are greatly improved, but the heat conduction performance of the resin insulation dry type transformer is influenced. The damage of the insulation material due to the temperature of the winding exceeding the thermal endurance limit of the insulation material is one of the main causes of the failure of the transformer, and thus the heat dissipation of the transformer is very important.
Disclosure of Invention
The invention aims to provide a flame-retardant heat-conducting dry-type transformer potting method to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme that the method for encapsulating the flame-retardant heat-conducting dry-type transformer comprises the steps of encapsulating heat-conducting epoxy resin to manufacture a heat-conducting inner core, wherein the heat-conducting epoxy resin comprises 100 parts by weight of liquid epoxy resin, 70-100 parts by weight of curing agent, 10-20 parts by weight of flexibilizer, 0.1-0.7 part by weight of accelerator, 0.1-0.5 part by weight of defoaming agent, 100 parts by weight of alumina powder and 500 parts by weight of high-heat-conductivity inorganic alumina powder is one or more of spherical alumina, spheroidal alumina and high-purity α -alumina.
The method comprises the following steps:
(1) 100 parts by weight of liquid epoxy resin is put into a defoaming kettle, stirring is started, 500 parts of alumina powder is put in when the temperature is raised to 70-100 ℃, and the pressure is reduced for 1-2 hours for defoaming after uniform stirring to obtain the component A.
(2)70-100 parts of curing agent and 10-20 parts of toughening agent are put into another defoaming kettle, 0.1-0.7 part of accelerant and 0.1-0.5 part of defoaming agent are put into the kettle after stirring, the mixture is uniformly stirred after being heated to 70-100 ℃, and then the pressure is reduced for 1-2 hours for defoaming to obtain a component B;
(3) adding the component A into the component B obtained in the step (2) in the stirring process, controlling the temperature of the material to be stable at 70-100 ℃, and injecting the material into a first vacuum mold of a dry-type transformer coil for casting molding;
(4) when the dry type transformer coil is cast and molded in vacuum, the temperature is controlled to be 70-100 ℃, the air pressure is controlled to be 100-150Pa, and the time is 0.5-2h, and the dry type transformer coil is demoulded and molded to form the heat-conducting inner core.
Then, manufacturing a flame-retardant layer on the outer layer of the heat-conducting inner core; 100 parts of flame-retardant heat-conducting epoxy resin by weight; 70-100 parts of a curing agent; 5-10 parts of a toughening agent; 1-10 parts of a diluent; 1-10 parts of a flame retardant; 0.01-0.7 part of dispersant; 0.01-0.8 part of defoaming agent and 40-60 parts of alumina. The flame retardant is one or a mixture of more of phosphate, magnesium hydroxide and silicon dioxide.
A flame-retardant heat-conducting dry-type transformer encapsulating method is characterized in that: the method comprises the following steps:
(1) and (2) putting 100 parts by weight of liquid epoxy resin into a defoaming kettle, stirring, adding 40-60 parts of alumina when the temperature is raised to 70-100 ℃, uniformly stirring, and decompressing for 1-2 hours for defoaming to obtain the component C.
(2)70-100 parts of curing agent, 5-10 parts of toughening agent and 1-10 parts of diluent; 1-10 parts of a flame retardant; 0.01-0.7 part of dispersant; 0.01-0.8 part of defoaming agent is added into another defoaming kettle, and after the temperature is raised to 70-100 ℃ while stirring, the pressure is reduced for 1-2h for defoaming to obtain a component D;
(3) adding the component C into the component D in the stirring process, controlling the temperature of the materials to be stable at 70-100 ℃, and injecting the materials into a second mold containing a heat-conducting inner core for vacuum casting molding;
(4) and during vacuum casting molding, controlling the temperature at 70-100 ℃, controlling the air pressure at 100-150Pa, and demolding and molding for 0.5-2h to manufacture the heat-conducting flame-retardant dry-type transformer.
Compared with the prior art, the invention has the beneficial effects that: the dry-type transformer manufactured by the invention has excellent flame retardance and heat conductivity, and the overall performance of the encapsulated dry-type transformer can be improved; the flame-retardant epoxy resin adopted by the invention has good high-temperature resistance, good toughness and high flame retardance, and further improves the flame retardance and heat conductivity of the transformer.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example (b):
manufacturing a heat conducting inner core; 100 parts of liquid epoxy resin according to parts by weight; 80 parts of a curing agent; 15 parts of a toughening agent; 0.5 part of an accelerator; 0.3 part of defoaming agent; 250 parts of alumina powder. The high heat conductivity inorganic alumina powder is spherical alumina.
The method comprises the following steps:
(1) 100 parts by weight of liquid epoxy resin is put into a defoaming kettle, stirring is started, 250 parts of alumina powder is put into the kettle when the temperature is raised to 80 ℃, and the components are uniformly stirred and decompressed for 2 hours for defoaming to obtain the component A.
(2)80 parts of curing agent and 15 parts of toughening agent are put into another defoaming kettle, 0.5 part of accelerant and 0.3 part of defoaming agent are put into the kettle after stirring, the mixture is uniformly stirred after being heated to 80 ℃, and then the pressure is reduced for 2 hours for defoaming, thus obtaining a component B;
(3) adding the component A into the component B obtained in the step (2) in the stirring process, controlling the temperature of the material to be stable at 90 ℃, and injecting the material into a first vacuum mold of a dry type transformer coil for casting molding;
(4) when the dry type transformer coil is molded by vacuum casting, the temperature is controlled at 90 ℃, the air pressure is controlled at 120Pa, and the demoulding and molding are carried out for 1 hour to manufacture the heat conducting inner core.
Then, encapsulating by adopting flame-retardant epoxy resin, wherein the flame-retardant epoxy resin comprises 100 parts by weight of liquid epoxy resin; 70 parts of a curing agent; 5 parts of a toughening agent; 1 part of diluent; 1 part of a flame retardant; 0.01 part of a dispersant; 0.01 part of defoaming agent and 40 parts of alumina.
The method comprises the following steps:
(1) and (3) putting 100 parts by weight of liquid epoxy resin into a defoaming kettle, starting stirring, adding 40 parts of alumina when the temperature is raised to 80 ℃, uniformly stirring, and decompressing for 1h for defoaming to obtain the component C.
(2)70 parts of curing agent, 5 parts of toughening agent and 1 part of diluent; 1 part of a flame retardant; 0.01 part of a dispersant; 0.01 part of defoaming agent is added into another defoaming kettle, and after the temperature is raised to 70 ℃ while stirring, the pressure is reduced for 2 hours for defoaming to obtain a component D;
(3) adding the component C into the component D in the stirring process, controlling the temperature of the material to be stable at 90 ℃, and injecting the material into a second mold containing a heat-conducting inner core for vacuum casting molding;
(4) and (3) during vacuum casting molding, controlling the temperature at 80 ℃ and the air pressure at 120Pa, and demolding and molding for 1h to manufacture the heat-conducting flame-retardant dry-type transformer.
In conclusion, the dry-type transformer manufactured by the invention has excellent flame retardance and heat conductivity, and the overall performance of the encapsulated dry-type transformer can be improved; the flame-retardant epoxy resin adopted by the invention has good high-temperature resistance, good toughness and high flame retardance, and further improves the flame retardance and heat conductivity of the transformer.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A flame-retardant heat-conducting dry-type transformer encapsulating method is characterized in that: encapsulating by using heat-conducting epoxy resin to manufacture a heat-conducting inner core; 100 parts of liquid epoxy resin according to parts by weight; 70-100 parts of a curing agent; 10-20 parts of a toughening agent; 0.1-0.7 part of an accelerator; 0.1-0.5 part of defoaming agent; 100 portions and 500 portions of alumina powder.
2. The method for encapsulating the flame-retardant and heat-conductive dry-type transformer according to claim 1, wherein the high-heat-conductivity inorganic alumina powder is one or more of spherical alumina, spheroidal alumina and high-purity α -alumina.
3. A heat-conducting epoxy resin dry-type transformer potting method is characterized in that: the method comprises the following steps:
(1) 100 parts by weight of liquid epoxy resin is put into a defoaming kettle, stirring is started, 500 parts of alumina powder is put in when the temperature is raised to 70-100 ℃, and the pressure is reduced for 1-2 hours for defoaming after uniform stirring to obtain the component A.
(2)70-100 parts of curing agent and 10-20 parts of toughening agent are put into another defoaming kettle, 0.1-0.7 part of accelerant and 0.1-0.5 part of defoaming agent are put into the kettle after stirring, the mixture is uniformly stirred after being heated to 70-100 ℃, and then the pressure is reduced for 1-2 hours for defoaming to obtain a component B;
(3) adding the component A into the component B obtained in the step (2) in the stirring process, controlling the temperature of the material to be stable at 70-100 ℃, and injecting the material into a first vacuum mold of a dry-type transformer coil for casting molding;
(4) when the dry type transformer coil is cast and molded in vacuum, the temperature is controlled to be 70-100 ℃, the air pressure is controlled to be 100-150Pa, and the time is 0.5-2h, and the heat conducting inner core is manufactured by demoulding and molding.
4. The method for potting a flame retardant and heat conductive dry type transformer according to claim 1, wherein: manufacturing a flame-retardant layer on the outer layer of the heat-conducting inner core; 100 parts of flame-retardant heat-conducting epoxy resin by weight; 70-100 parts of a curing agent; 5-10 parts of a toughening agent; 1-10 parts of a diluent; 1-10 parts of a flame retardant; 0.01-0.7 part of dispersant; 0.01-0.8 part of defoaming agent and 40-60 parts of alumina.
5. The method for potting a flame retardant and heat conductive dry type transformer according to claim 4, wherein: the flame retardant is one or a mixture of more of phosphate, magnesium hydroxide and silicon dioxide.
6. The method for potting a flame retardant and heat conductive dry type transformer according to claim 4, wherein: the method comprises the following steps:
(1) and (2) putting 100 parts by weight of liquid epoxy resin into a defoaming kettle, stirring, adding 40-60 parts of alumina when the temperature is raised to 70-100 ℃, uniformly stirring, and decompressing for 1-2 hours for defoaming to obtain the component C.
(2)70-100 parts of curing agent, 5-10 parts of toughening agent and 1-10 parts of diluent; 1-10 parts of a flame retardant; 0.01-0.7 part of dispersant; 0.01-0.8 part of defoaming agent is added into another defoaming kettle, and after the temperature is raised to 70-100 ℃ while stirring, the pressure is reduced for 1-2h for defoaming to obtain a component D;
(3) adding the component C into the component D in the stirring process, controlling the temperature of the materials to be stable at 70-100 ℃, and injecting the materials into a second mold containing a heat-conducting inner core for vacuum casting molding;
(4) and during vacuum casting molding, controlling the temperature at 70-100 ℃, controlling the air pressure at 100-150Pa, and demolding and molding for 0.5-2h to manufacture the heat-conducting flame-retardant dry-type transformer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911389442.9A CN111063521A (en) | 2019-12-30 | 2019-12-30 | Flame-retardant heat-conducting dry-type transformer encapsulating method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911389442.9A CN111063521A (en) | 2019-12-30 | 2019-12-30 | Flame-retardant heat-conducting dry-type transformer encapsulating method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114290765A (en) * | 2022-01-11 | 2022-04-08 | 江西省航宇新材料股份有限公司 | Superconductive aluminum-based copper-clad plate and manufacturing method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101567258A (en) * | 2009-02-12 | 2009-10-28 | 天津光电万泰克电子有限公司 | Vacuum encapsulation technology for transformer |
| CN106433533A (en) * | 2016-07-27 | 2017-02-22 | 苏州巨峰电气绝缘系统股份有限公司 | Outdoor high-low-temperature-resistant and thermally-conductive epoxy encapsulating resin and preparation method thereof |
-
2019
- 2019-12-30 CN CN201911389442.9A patent/CN111063521A/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101567258A (en) * | 2009-02-12 | 2009-10-28 | 天津光电万泰克电子有限公司 | Vacuum encapsulation technology for transformer |
| CN106433533A (en) * | 2016-07-27 | 2017-02-22 | 苏州巨峰电气绝缘系统股份有限公司 | Outdoor high-low-temperature-resistant and thermally-conductive epoxy encapsulating resin and preparation method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114290765A (en) * | 2022-01-11 | 2022-04-08 | 江西省航宇新材料股份有限公司 | Superconductive aluminum-based copper-clad plate and manufacturing method thereof |
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Application publication date: 20200424 |