Organic paste having gradient volatilization rate and method for preparing the same

Abstract

To provide an organic paste having a gradient volatilization rate and a method of preparing the same.SOLUTION: An organic paste comprises a rare earth powder, organic solvent and resin, and further a dispersant and / or an anti-settling agent and / or a synergist, having components by weight percentage of 50%-90% of a rare earth powder, 8%-50% of organic solvent, 0.4%-6% of resin, 0%-5% of a dispersant, 0%-3% of an anti-settling agent and 0%-3% of a synergist. The method of preparing includes: weighing a rare earth powder, organic solvent, resin, a dispersant and / or an anti-settling agent and / or a synergist by weight percentage respectively; obtaining an organic carrier by adding weighed components in order into a mixer so that they are stirred at constant temperature and then cooled down to room temperature; obtaining a coarse organic paste by adding the organic carrier and the rare earth powder weighed into a vacuum high-speed disperser; and obtaining a fine organic paste by transferring the coarse organic paste into a gap-adjustable triple roll mill to perform abrasion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the field of screen printing technology, and more particularly to an organic paste having a gradient volatilization rate and a method for preparing the same. [Background technology]

[0002] Since the discovery of NdFeB (neodymium iron boron) permanent magnet material in the 1980s, its excellent properties such as high residual magnetism, coercivity, and maximum magnetic energy product have led to its widespread use in many fields, including the electronics and medical industries. In recent years, to satisfy the performance requirements of sintered neodymium magnets used in drive motors for new energy vehicles and direct-drive permanent magnet units for wind power generation, it is usually necessary to improve the coercivity of the magnets by applying grain boundary diffusion treatment. Conventional grain boundary diffusion often involves applying heavy rare earth monomers, fluorides, hydrides, oxides, and alloys to the magnet surface using methods such as sputtering, vapor deposition, electrophoresis, surface coating, and impregnation, using these as diffusion sources. However, the above diffusion sources have low diffusion efficiency, require large quantities, and there is no low-cost grain boundary diffusion process suitable for industrialized, large-scale, and stable production, which has limited the development and application of high-end NdFeB magnets.

[0003] To overcome the shortcomings of existing grain boundary diffusion methods, screen printing technology is being applied to the neodymium industry. Screen printing involves using a screen stencil and paste, where the paste is printed onto a substrate through the holes in the stencil by scraping. Screen printing combines the advantages of both sputtering and surface coating methods, offering low cost, high production efficiency, and easy automation, making it a promising development as the mainstream process for NdFeB grain boundary diffusion. The paste, as a raw material for screen printing, directly influences the printing and subsequent diffusion effects.

[0004] Conventional techniques primarily involve dispersing rare earth powders in organic solutions such as alcohol / acetone while stirring. Organic pastes struggle to simultaneously meet the requirements of low volatility at room temperature and high volatility at high temperatures. High volatility at room temperature leads to large amounts of organic solvent evaporating during the printing process, increasing the viscosity of the paste and making it difficult to pass through the screen. Conversely, low volatility at high temperatures not only prolongs drying time but also causes flow in the coated film layer, resulting in a non-uniform film layer and ultimately affecting the diffusion effect. [Overview of the project]

[0005] The object of the present invention is to provide an organic paste having a gradient volatilization rate and a method for preparing the same, thereby solving at least one of the above technical problems and enabling gradient volatilization of the paste.

[0006] Embodiments of the present invention are realized as follows.

[0007] An organic paste having a gradient volatilization rate, comprising rare earth powder, organic solvent and resin, further comprising a dispersant and / or anti-settling agent and / or synergistic agent, wherein the weight percentage of each component is: Rare earth powder 50%~90%, Organic solvents 8% to 50%, Resin 0.4%~6%, Dispersant 0%~5%, Anti-settlement agent 0%~3%, The synergistic effect is present in 0% to 3% of the total.

[0008] In a preferred embodiment of the present invention, the rare earth powder in the NdFeB screen printing organic paste comprises one or a mixture of two selected from a pure metal powder of a heavy rare earth element, an alloy powder containing a heavy or light rare earth element, and a heavy rare earth powder containing hydrides, fluorides, and oxides of a heavy rare earth element.

[0009] In preferred embodiments of the present invention, the pure metal powder in the above-mentioned organic paste for NdFeB screen printing comprises one or more of Tb, Dy, Ho, and Gd, The alloy powder is composed of RExMy in weight percent, where RE is one or more of Tb, Dy, Ho, Gd, Pr, Nd, La, Ce, and Y, and M is one or more of Ga, Cu, Al, Ni, and Fe, with 60 ≤ x ≤ 95 and 5 ≤ y ≤ 40.

[0010] In a preferred embodiment of the present invention, the particle size of the rare earth powder in the NdFeB screen printing organic paste is D50 < 3 μm.

[0011] In preferred embodiments of the present invention, the organic solvent in the above-mentioned NdFeB screen printing organic paste comprises one or more of the following: propylene glycol phenyl ether, DBE, methyl isobutyl ketone, and propylene glycol methyl ether acetate.

[0012] In preferred embodiments of the present invention, the resin in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: ethylcellulose, polyvinyl butyral, acrylic resin, vinyl chloride resin, polyester resin, and polyurethane.

[0013] As a technical effect, the resin improves the adhesion of the organic paste to the substrate and ensures subsequent grain boundary diffusion.

[0014] In a preferred embodiment of the present invention, the dispersant in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: polyvinyl butyral, polyvinylpyrrolidone, sodium polyacrylate, and polyvinylamide.

[0015] As a technical effect, the dispersant prevents the re-aggregation of the diffusion source powder in the organic paste, reduces the powderiness of the organic paste itself, and improves the homogeneity of the weight increase during screen printing.

[0016] In preferred embodiments of the present invention, the anti-settling agent in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: polyamide wax, polyethylene wax, organic bentonite, and fumed silica.

[0017] As a technical effect, the aforementioned settling inhibitor improves the stability of the organic paste during standing, suppresses the occurrence of delamination, and further reduces the volatilization rate at room temperature.

[0018] In preferred embodiments of the present invention, the synergistic agent in the above-mentioned organic paste for NdFeB screen printing is one or more of the modified polyhydroxycarboxylic acid ester, BYK-SYNERGIST 2105, and BYK-SYNERGIST 2100, as well as a mixture of two or more of these.

[0019] As a technical effect, the synergistic agent can improve the mesh structure of the organic carrier.

[0020] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Pure metal powder 65%~75%, 10% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. 0.4% to 4% of one or more of ethylcellulose, polyvinyl butyral, and polyester resin. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0021] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Alloy powder 70%~80%, 20% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. One or more of acrylic resin, polyurethane, and polyester resin in a concentration of 0.4% to 5%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0022] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Heavy rare earth powder 60%~80%, 10% to 30% of one or two of DBE and propylene glycol methyl ether acetate, One or more of the following materials: polyvinyl chloride resin, polyester resin, and polyurethane, in an amount of 0.4% to 4%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0023] A method for preparing an organic paste having the gradient volatilization rate described above, Weigh the rare earth powder, organic solvent, resin, dispersant and / or anti-settling agent and / or synergistic agent, each in weight percentage, The weighed rare earth powder, the organic solvent, the resin, the dispersant and / or the anti-settling agent and / or the synergistic agent are sequentially added to a mixer, stirred at a constant temperature of 20 to 70°C at a rotation speed of 600 r / min to 1200 r / min for 0.25 to 6 hours, and then cooled to room temperature to obtain an organic carrier. As a result of this technology, the manufactured organic carrier is homogeneous and free from aggregated substances. The organic carrier and the weighed rare earth powder are added to a vacuum high-speed disperser and dispersed at a rotation speed of 1000 r / min to 4000 r / min for 0.25 to 1 hour to obtain a crude organic paste. As a result of this technology, the manufactured crude organic paste is free of air bubbles and is homogeneously dispersed. The process includes transferring the aforementioned coarse organic paste to a gap-adjustable three-roller mill and polishing it 1 to 3 times to obtain a fine organic paste, As a result of this technology, the fine organic paste produced has a particle size of less than 5 μm.

[0024] The beneficial effects of the embodiments of the present invention are as follows:

[0025] The present invention provides an organic paste having a gradient volatilization rate and a method for preparing the same, which establishes a gradient of organic components and forms an organic carrier in a mesh structure through strong polishing interactions, thereby achieving a gradient volatilization rate of less than 0.05% / h at room temperature and more than 1.2% / h at high temperatures of 120°C. The prepared organic paste for screen printing of rare earth permanent magnet materials has a low volatilization rate at room temperature, effectively preventing clogging and uneven printing due to the volatilization of organic solvents during printing. At high temperatures, its volatilization rate is high and the curing time is short, significantly reducing drying time, improving processing efficiency, and reducing the amount of oxygen, carbon, and other impurities that penetrate the magnet during the curing and subsequent heat treatment stages. [Brief explanation of the drawing]

[0026] To more clearly explain the technical solutions of the embodiments of the present invention, the drawings used in the embodiments are briefly introduced below. However, these drawings merely illustrate specific embodiments of the present invention and should not be considered limiting in scope. Those skilled in the art should understand that other relevant drawings can be obtained based on these drawings without requiring any creative effort. [Figure 1] This is a schematic diagram showing the flow of the method for preparing an organic paste having a gradient volatilization rate according to the present invention. [Figure 2] This is a schematic diagram of the volatilization profiles of an example of an organic paste having a gradient volatilization rate according to the present invention, held at 40°C, 80°C, and 120°C for 2 hours. [Figure 3] This is a schematic diagram of the volatilization profile of a comparative example of an organic paste having a gradient volatilization rate according to the present invention, held at 40°C, 80°C, and 120°C for 2 hours. [Figure 4] This is a schematic diagram showing a metallographic image of the surface of a coating film after drying an example of an organic paste having a gradient volatilization rate according to the present invention at 120°C for 10 minutes. [Modes for carrying out the invention]

[0027] To more clearly explain the object, technical solution, and advantages of the embodiments of the present invention, the following will clearly and completely describe the technical solution in the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. It should be noted that the described embodiments are only a part of the embodiments of the present invention, not all of them. In general, the components of the embodiments of the present invention described and illustrated in the drawings can be arranged and designed in various configurations.

[0028] A first embodiment of the present invention provides an organic paste having a gradient volatilization rate, comprising rare earth powder, an organic solvent and a resin, and further comprising a dispersant and / or a settling inhibitor and / or a synergistic agent, wherein the weight percentage of each component is: Rare earth powder 50%~90%, Organic solvents 8% to 50%, Resin 0.4%~6%, Dispersant 0%~5%, Anti-settlement agent 0%~3%, The synergistic effect is present in 0% to 3% of the total.

[0029] Preferably, the weight percentage of each component is Rare earth powder 60%~80%, 10% to 30% organic solvents, Resin 0.4%~5%, Dispersant 0%~3%, Anti-settlement agent 0%~2%, The synergistic effect is present in 0% to 2% of the product.

[0030] In a preferred embodiment of the present invention, the rare earth powder in the NdFeB screen printing organic paste comprises one or a mixture of two selected from a pure metal powder of a heavy rare earth element, an alloy powder containing a heavy or light rare earth element, and a heavy rare earth powder containing hydrides, fluorides, and oxides of a heavy rare earth element.

[0031] In preferred embodiments of the present invention, the pure metal powder in the above-mentioned organic paste for NdFeB screen printing comprises one or more of Tb, Dy, Ho, and Gd.

[0032] The alloy powder is composed of RE by weight percentage x M y where RE is one or a mixture of two or more of Tb, Dy, Ho, Gd, Pr, Nd, La, Ce, Y, and M is one or a mixture of two or more of Ga, Cu, Al, Ni, Fe, and 60 ≦ x ≦ 95, 5 ≦ y ≦ 40.

[0033] In a preferred embodiment of the present invention, the pure metal powder in the above-mentioned NdFeB screen printing organic paste contains one or two of Tb and Dy.

[0034] The alloy powder is composed of RE by weight percentage x M y where RE is one or a mixture of two or more of Tb, Dy, Pr, Nd. When RE is Tb, M is one or a mixture of two or more of Ga, Cu, Al, Ni, and 70 ≦ x ≦ 90, 10 ≦ y ≦ 30. When RE is Dy, M is one or a mixture of two or more of Ni, Fe, Ga, and 60 ≦ x ≦ 80, 20 ≦ y ≦ 40. When RE is two or three of Tb, Pr, Nd, M is one or a mixture of two of Cu and Al, and 80 ≦ x ≦ 95, 5 ≦ y ≦ 20. By adding the above alloy elements, the melting point of the diffusion source decreases, the diffusion changes from solid-liquid diffusion to liquid-liquid diffusion, and the diffusion efficiency is greatly improved. In addition, after the above alloy elements diffuse into the magnet, most of them are distributed at the grain boundaries, and the intergranular magnetic exchange coupling can be reduced.

[0035] In a preferred embodiment of the present invention, the particle size of the rare earth powder in the above-mentioned NdFeB screen printing organic paste is D50 < 3 μm.

[0036] Preferably, the particle size of the rare earth powder is 1.6 < D50 < 2.4. When the particle size of the powder is within this range, due to the small particle size of the powder, the preparation efficiency of the powder will not be significantly reduced, and excellent stability can be obtained.

[0037] In preferred embodiments of the present invention, the organic solvent in the above-mentioned NdFeB screen printing organic paste comprises one or more of the following: propylene glycol phenyl ether, DBE, methyl isobutyl ketone, and propylene glycol methyl ether acetate.

[0038] Preferably, the organic solvent is one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. Since the organic solvent is easily volatilized at high temperatures, it improves the drying efficiency after screen printing, reduces impurities such as C and O into the magnet during grain boundary diffusion, and ensures the magnet's performance after diffusion.

[0039] In preferred embodiments of the present invention, the resin in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: ethylcellulose, polyvinyl butyral, acrylic resin, vinyl chloride resin, polyester resin, and polyurethane.

[0040] Preferably, the resin is a mixture of one or more of polyvinyl butyral, polyvinyl chloride resin, polyester resin, and polyurethane. The resin has a high molecular weight, can significantly improve the viscosity of the organic paste with only a small amount added, has a low thermal decomposition rate, and can reduce the penetration of C and O elements into the magnet through grain boundary diffusion treatment.

[0041] As a technical effect, the resin improves the adhesion of the organic paste to the substrate and ensures subsequent grain boundary diffusion.

[0042] In a preferred embodiment of the present invention, the dispersant in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: polyvinyl butyral, polyvinylpyrrolidone, sodium polyacrylate, and polyvinylamide.

[0043] Preferably, the dispersant is a mixture of one or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide, and the dispersant is advantageous for dispersing the diffusion source powder because it is readily soluble in organic solvents and has good wettability to the diffusion source powder.

[0044] As a technical effect, the dispersant prevents the re-aggregation of the diffusion source powder in the organic paste, reduces the powderiness of the organic paste itself, and improves the homogeneity of the weight increase during screen printing.

[0045] In preferred embodiments of the present invention, the anti-settling agent in the above-mentioned organic paste for NdFeB screen printing comprises one or more of the following: polyamide wax, polyethylene wax, organic bentonite, and fumed silica.

[0046] Preferably, the settling inhibitor comprises one or a mixture of polyamide wax and polyethylene wax, and since the settling inhibitor decomposes completely at high temperatures, it can reduce the amount of carbon remaining on the magnet surface during high-temperature grain boundary diffusion. As a technical effect, the settling inhibitor can improve the stability of the organic paste during standing, suppress the occurrence of delamination, and further reduce the volatilization rate at room temperature.

[0047] In preferred embodiments of the present invention, the synergistic agent in the above-mentioned organic paste for NdFeB screen printing is one or more of the modified polyhydroxycarboxylic acid ester, BYK-SYNERGIST 2105, and BYK-SYNERGIST 2100, as well as a mixture of two or more of these.

[0048] Preferably, the synergistic agent is a modified polyhydroxycarboxylic acid ester, and the addition of the synergistic agent significantly improves the high-temperature drying rate of the organic paste without affecting the room-temperature volatilization rate, thereby reliably achieving a gradient volatilization rate.

[0049] As a technical effect, the synergistic agent can improve the mesh structure of the organic carrier.

[0050] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Pure metal powder 65%~75%, 10% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. 0.4% to 4% of one or more of ethylcellulose, polyvinyl butyral, and polyester resin. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0051] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Alloy powder 70%~80%, 20% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. One or more of acrylic resin, polyurethane, and polyester resin in a concentration of 0.4% to 5%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0052] In preferred embodiments of the present invention, the weight percentage of each component in the above NdFeB screen printing organic paste is: Heavy rare earth powder 60%~80%, 10% to 30% of one or two of DBE and propylene glycol methyl ether acetate, One or more of the following materials: polyvinyl chloride resin, polyester resin, and polyurethane, in an amount of 0.4% to 4%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in a concentration of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% It consists of one or more of the modified polyhydroxycarboxylic acid esters, BYK-SYNERGIST 2105 and BYK-SYNERGIST 2100, in an amount of 0% to 2%.

[0053] Referring to Figure 1, a second embodiment of the present invention provides a method for preparing an organic paste having the gradient volatilization rate described above. Weigh the rare earth powder, organic solvent, resin, dispersant and / or anti-settling agent and / or synergistic agent, each in weight percentage, The weighed rare earth powder, the organic solvent, the resin, the dispersant and / or the anti-settling agent and / or the synergistic agent are sequentially added to a mixer, stirred at a constant temperature of 20 to 70°C at a rotation speed of 600 r / min to 1200 r / min for 0.25 to 6 hours, and then cooled to room temperature to obtain an organic carrier. As a result of this technology, the manufactured organic carrier is homogeneous and free from aggregated substances. The organic carrier and the weighed rare earth powder are added to a vacuum high-speed disperser and dispersed at a rotation speed of 1000 r / min to 4000 r / min for 0.25 to 1 hour to obtain a crude organic paste. As a result of this technology, the manufactured crude organic paste is free of air bubbles and is homogeneously dispersed. The process includes transferring the aforementioned coarse organic paste to a gap-adjustable three-roller mill and polishing it 1 to 3 times to obtain a fine organic paste, As a technical effect, the powder fineness of the produced fine organic paste is less than 5 μm.

[0054] Specifically, the following examples and comparative examples are used to further elaborate on the implementation effects of the present invention. The distribution of various components in each example is shown in Table 1.

[0055]

Table 1

Example

[0056] 70%Dy 80 Ni 20 Diffusion source powder, 15% propylene glycol methyl ether acetate, 10% DBE, 1% vinyl chloride resin, 2% polyester resin, 2% sodium polyacrylate are weighed in weight percentages. Here, Dy 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.83 μm.

[0057] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, and sodium polyacrylate are sequentially added to a mixer and stirred at a constant temperature of 60 °C at a rotation speed of 1200 r / min for 5 hours to obtain a homogeneous and non-agglomerating organic carrier.

[0058] Dy 80 Ni 20 The diffusion source powder and the prepared organic carrier are added to a vacuum high-speed disperser and highly dispersed at a rotation speed of 2200 r / min for 25 minutes to preliminarily prepare an organic paste. Then, the organic paste obtained by high-speed dispersion is transferred to a three-roll mill and polished twice to obtain an organic paste with a powder fineness of less than 5 μm.

Example

[0059] 70% Tb 83 Cu7Al 10 The diffusion source powder, 10% methyl isobutyl ketone, 12% polyester resin, 2% acrylic resin, 0.4% polyvinylpyrrolidone, 0.6% polyvinylamide, 3% organic bentonite, and 2% BYK-SYNERGIST 2100 were weighed in weight percent, where Tb 80 Cu 10 Al 10 The particle size of the diffusion source powder is D50 = 2.54 μm.

[0060] Methyl isobutyl ketone, polyester resin, acrylic resin, polyvinylpyrrolidone, polyvinylamide, organic bentonite, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 1000 r / min for 25 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0061] Tb 80 Cu 10 Al 10 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0062] 70% Dy diffusion source powder, 10% propylene glycol, 16% methyl ether acetate, 3% polyester resin, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 2.31 μm.

[0063] Propylene glycol, methyl ether acetate, polyester resin, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 50°C and a rotation speed of 900 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0064] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0065] 70%Pr 90 Al5Ga5 diffusion source powder, 11% methyl isobutyl ketone, 11% polyester resin, 0.5% polyurethane, 1.5% polyester resin, 0.5% polyvinylpyrrolidone, 0.5% polyvinylamide, 1% polyamide wax, 1% polyethylene wax, and 3% BYK-SYNERGIST 2105 were weighed in weight percent, and here, Pr 90 The particle size of the Cu5Ga5 diffusion source powder is D50 = 1.89 μm.

[0066] Methyl isobutyl ketone, polyester resin, polyurethane, polyester resin, polyvinylpyrrolidone, polyvinylamide, polyamide wax, polyethylene wax, and BYK-SYNERGIST 2105 were sequentially added to a mixer and stirred at a constant temperature of 30°C and a rotation speed of 1000 r / min for 1 hour to obtain a homogeneous, non-aggregating organic carrier.

[0067] Pr 90 Cu5Ga5 diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0068] 70% Dy 80 Ni 20The diffusion source powder, 12% propylene glycol methyl ether acetate, 12.5% ​​DBE, 1% vinyl chloride resin, 2% polyester resin, 2% sodium polyacrylate, and 0.5% modified polyhydroxycarboxylic acid ester were weighed in weight percent, and here, Dy 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.5 μm.

[0069] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 60°C and a rotation speed of 1000 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0070] Dy 80 Ni 20 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0071] 60% Tb-H diffusion source powder, 35% propylene glycol phenyl ether, and 5% ethyl cellulose were weighed out by weight percentage, where the particle size of the Tb-H diffusion source powder was D50 = 1.99 μm.

[0072] Propylene glycol phenyl ether and ethyl cellulose were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0073] The Tb-H diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0074] 70% DyO diffusion source powder, 23% propylene glycol methyl ether acetate, 1% polyester resin, 1% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed out in weight percentages, where the particle size of the TbO diffusion source powder was D50 = 2.27 μm.

[0075] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 4 hours to obtain a homogeneous, non-aggregating organic carrier.

[0076] The DyO diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0077] 90% TbH diffusion source powder, 8% propylene glycol phenyl ether, and 2% ethyl cellulose were weighed out in weight percentages, where the particle size of the TbH diffusion source powder was D50 < 2.5 μm.

[0078] Propylene glycol phenyl ether and ethyl cellulose were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0079] The Tb-H diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2500 r / min for 50 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0080] 70% TbF diffusion source powder, 12% propylene glycol methyl ether acetate, 10.5% DBE, 1.5% vinyl chloride resin, 1.5% polyester resin, 2% sodium polyacrylate, and 2.5% modified polyhydroxycarboxylic acid ester were weighed in weight percent, where Tb 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.33 μm.

[0081] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0082] The TbF diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0083] 70% TbO diffusion source powder, 20% propylene glycol methyl ether acetate, 4% polyester resin, 1% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed out in weight percentages, where the particle size of the TbO diffusion source powder was D50 = 2.17 μm.

[0084] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 60°C and a rotation speed of 1000 r / min for 5.5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0085] TbO metal powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 40 minutes to pre-prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0086] 70% Tb diffusion source powder, 24% DBE, 4% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 1.63 μm.

[0087] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0088] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 15 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0089] 50% Tb-H diffusion source powder, 44% propylene glycol phenyl ether, and 6% ethyl cellulose were weighed out by weight percentage, where the particle size of the Tb-H diffusion source powder was D50 = 2.43 μm.

[0090] Propylene glycol phenyl ether and ethyl cellulose were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0091] The Tb-H diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0092] 70% Dy diffusion source powder, 12% propylene glycol, 12% methyl ether acetate, 3% polyester resin, 2% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 1.67 μm.

[0093] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 45°C and a rotation speed of 1000 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0094] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0095] 70% Tb diffusion source powder, 15% DBE, 12.6% polyurethane, 0.4% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 1.84 μm.

[0096] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 20 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0097] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0098] 70% TbF diffusion source powder, 11% propylene glycol methyl ether acetate, 12% DBE, 1.5% vinyl chloride resin, 1.5% polyester resin, 2% sodium polyacrylate, and 2% modified polyhydroxycarboxylic acid ester were weighed in weight percent, where Tb 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.45 μm.

[0099] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 70°C and a rotation speed of 1200 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0100] The TbF diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 40 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0101] 70% Tb 60 Ni 40 The diffusion source powder, 10% propylene glycol methyl ether acetate, 13.5% DBE, 2% vinyl chloride resin, 1% polyester resin, 2% sodium polyacrylate, and 1.5% modified polyhydroxycarboxylic acid ester were weighed in weight percent, where Tb 60 Ni 40 The particle size of the diffusion source powder is D50 = 2.25 μm.

[0102] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 65°C and a rotation speed of 1200 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0103] Tb 60 Ni 40 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0104] 70% TbO diffusion source powder, 23% propylene glycol methyl ether acetate, 1% polyester resin, 1% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed in weight percentages, where the particle size of the TbO diffusion source powder was D50 < 3 μm.

[0105] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 45°C and a rotation speed of 1000 r / min for 4 hours to obtain a homogeneous, non-aggregating organic carrier.

[0106] The TbO diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 35 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0107] 70% Dy diffusion source powder, 9% propylene glycol, 12% methyl ether acetate, 3% polyester resin, 5% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 2.46 μm.

[0108] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1200 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0109] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0110] 5% Tb 82 Fe 18 , 25% La 80 Al20 , 30% Ce 80 Fe 20 The diffusion source powder, 10% propylene glycol, 12% methyl ether acetate, 2% polyester resin, 1% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, 1.5% modified polyhydroxycarboxylic acid ester, and 1.5% BYK-SYNERGIST 2100 were weighed in weight percent, where Tb 82 Fe 18 La 80 Al 20 Ce 80 Fe 20 The particle sizes D50 of the diffusion source powders are 2.33, 2.17, and 2.48 μm, respectively.

[0111] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, modified polyhydroxycarboxylic acid ester, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0112] Tb 82 Fe 180 La 80 Al 20 Ce 80 Fe 20 Metal powder and a prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0113] 5%Nd 90 Cu5Al5, 60%Dy 90Weigh the following in weight percent: Cu5Al5, 5% TbF diffusion source powder, 10% propylene glycol methyl ether acetate, 12% methyl isobutyl ketone, 2% polyester resin, 1% polyvinylpyrrolidone, 1% polyamide wax, 1% polyethylene wax, 2% modified polyhydroxycarboxylic acid ester, and 1% BYK-SYNERGIST 2100, where Nd 90 Cu5Al5, Dy 90 The particle sizes D50 of the Cu5Al5 and TbF diffusion source powders are 1.73, 2.07, and 1.88 μm, respectively.

[0114] Propylene glycol methyl ether acetate, methyl isobutyl ketone, polyester resin, polyvinylpyrrolidone, polyamide wax, polyethylene wax, modified polyhydroxycarboxylic acid ester, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0115] Nd 90 Cu5Al5, Dy 90 Cu5Al5, TbF diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0116] 5%Nd 90 Cu5Al5, 50%Dy 90 Cu5Al5, 15%Dy 80 Fe 20 The diffusion source powder, 22% methyl isobutyl ketone, 2% acrylic resin, 0.5% polyvinylpyrrolidone, 0.5% polyvinylamide, 2% polyamide wax, and 3% BYK-SYNERGIST 2105 were weighed in weight percent, where Nd 90 Cu5Al5, Dy 90 Cu5Al5, Dy 80 Fe20 The particle sizes D50 of the diffusion source powders are 2.02, 2.13, and 2.27 μm, respectively.

[0117] Methyl isobutyl ketone, acrylic resin, polyvinylpyrrolidone, polyvinylamide, polyamide wax, and BYK-SYNERGIST 2105 were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 1000 r / min for 20 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0118] Nd 90 Cu5Al5, Dy 90 Cu5Al5, Dy 80 Fe 20 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 40 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0119] 80% Tb-H diffusion source powder, 17% propylene glycol phenyl ether, and 3% ethyl cellulose were weighed out by weight percentage, where the particle size of the Tb-H diffusion source powder was D50 = 1.67 μm.

[0120] Propylene glycol phenyl ether and ethyl cellulose were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0121] The Tb-H diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 45 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0122] 10% Tb, 20% Nd 90 Cu5Al5, 40%Tb 90 The following components were weighed in weight percent: Cu5Ho5 diffusion source powder, 10% methyl isobutyl ketone, 12% polyester resin, 0.5% polyurethane, 1.5% polyester resin, 0.6% polyvinylpyrrolidone, 0.4% polyvinylamide, 0.5% polyamide wax, 1.5% polyethylene wax, and 3% BYK-SYNERGIST 2105, where Tb and Nd 90 Cu5Al5, Tb 90 The particle size D50 of the Cu5Ho5 diffusion source powders is 1.45, 1.56, and 1.73 μm, respectively.

[0123] Methyl isobutyl ketone, polyester resin, polyurethane, polyester resin, polyvinylpyrrolidone, polyvinylamide, polyamide wax, polyethylene wax, and BYK-SYNERGIST 2105 were sequentially added to a mixer and stirred at a constant temperature of 70°C and a rotation speed of 1200 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0124] Tb, Nd 90 Cu5Al5, Tb 90 Cu5Ho5 diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0125] 70% Tb 80 Cu 10 Al 10 The diffusion source powder, 22% methyl isobutyl ketone, 3% acrylic resin, 0.5% polyvinylpyrrolidone, 0.5% polyvinylamide, 2% polyamide wax, and 2% BYK-SYNERGIST 2100 were weighed in weight percent, and here, Tb 80 Cu 10 Al 10 The particle size of the diffusion source powder is D50 <= 2.17 μm.

[0126] Methyl isobutyl ketone, acrylic resin, polyvinylpyrrolidone, polyvinylamide, polyamide wax, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a rotation speed of 1000 r / min for 25 minutes at a constant temperature of 25 °C to obtain a homogeneous and non-cohesive organic carrier.

[0127] Tb 80 Cu 10 Al 10 The prepared organic carrier and the diffusion source powder were added to a vacuum high-speed disperser and highly dispersed at a rotation speed of 2200 r / min for 25 minutes to preliminarily prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roll mill and polished once to obtain an organic paste with a powder fineness of less than 5 μm.

Example

[0128] 70% TbF diffusion source powder, 10% propylene glycol methyl ether acetate, 12% DBE, 2% vinyl chloride resin, 1% polyester resin, 2% sodium polyacrylate, and 3% modified polyhydroxycarboxylic acid ester were weighed by weight percentage. Here, Tb 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.36 μm.

[0129] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a rotation speed of 1200 r / min for 4 hours at a constant temperature of 55 °C to obtain a homogeneous and non-cohesive organic carrier.

[0130] The prepared organic carrier and the TbF diffusion source powder were added to a vacuum high-speed disperser and highly dispersed at a rotation speed of 2200 r / min for 25 minutes to preliminarily prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roll mill and polished once to obtain an organic paste with a powder fineness of less than 5 μm.

Example

[0131] 70% Tb diffusion source powder, 22% DBE, 6% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 2.53 μm.

[0132] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 1000 r / min for 30 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0133] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0134] 70% Tb diffusion source powder, 23% DBE, 5% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 1.93 μm.

[0135] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 25 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0136] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0137] 70% Tb diffusion source powder, 10% DBE, 16% polyurethane, 2% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 2.07 μm.

[0138] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 600 r / min for 40 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0139] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 35 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0140] 70% Dy 80 Ni 20 The diffusion source powder, 11% propylene glycol methyl ether acetate, 12% DBE, 3% polyester resin, 2% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed in weight percent, and here, Dy 80 Ni 20 The particle size of the diffusion source powder is D50 = 2.5 μm; Propylene glycol methyl ether acetate, DBE, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 4 hours to obtain a homogeneous, non-aggregating organic carrier.

[0141] Dy 80 Ni 20The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotational speed of 2200 r / min for 25 minutes to preliminarily prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roll mill and polished once to obtain an organic paste with a powder fineness of less than 5 μm.

Example

[0142] Weigh 70% Tb diffusion source powder, 10% DBE, 17% polyurethane, 1% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester by weight percentage. Here, the particle size of the Tb diffusion source powder is D50 = 2.36 μm.

[0143] Add DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester to the mixer sequentially, and stir at a rotational speed of 900 r / min for 20 minutes at a constant temperature of 25°C to obtain a homogeneous and non-agglomerating organic carrier.

[0144] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotational speed of 2200 r / min for 30 minutes to preliminarily prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roll mill and polished twice to obtain an organic paste with a powder fineness of less than 5 μm.

Example

[0145] 70%Tb 80 Cu 10 Al 10 Weigh 28% diffusion source powder, 22% methyl isobutyl ketone, 3% acrylic resin, 0.5% polyvinyl pyrrolidone, 0.5% polyvinyl amide, 1% polyamide wax, and 3% BYK-SYNERGIST 2100 by weight percentage. Here, 80 Cu 10 Al 10 the particle size of the diffusion source powder is D50 = 1.91 μm.

[0146] Methyl isobutyl ketone, acrylic resin, polyvinylpyrrolidone, polyvinylamide, polyamide wax, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 1000 r / min for 25 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0147] Tb 80 Cu 10 Al 10 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 45 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0148] 70% TbO diffusion source powder, 22% propylene glycol methyl ether acetate, 2% polyester resin, 2% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed out in weight percentages, where the particle size of the TbO diffusion source powder was D50 = 2.38 μm.

[0149] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 45°C and a rotation speed of 1000 r / min for 4 hours to obtain a homogeneous, non-aggregating organic carrier.

[0150] The TbO diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0151] 30%Nd 90Cu5Al5, 20%Y 80 Fe 20 Weighing 20% ​​Tb diffusion source powder, 10% propylene glycol methyl ether acetate, 12% DBE, 0.5% polyester resin, 1.5% polyester resin, 1% acrylic resin, 2% polyamide wax, 1% modified polyhydroxycarboxylic acid ester, and 2% BYK-SYNERGIST 2105 in weight percent, where Nd 90 Cu5Al5,Y 80 Fe 20 The particle size D50 of the Tb diffusion source powders is 1.67, 1.85, and 2.02 μm, respectively.

[0152] Propylene glycol methyl ether acetate, DBE, polyester resin, polyester resin, acrylic resin, polyamide wax, modified polyhydroxycarboxylic acid ester, and BYK-SYNERGIST 2105 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1200 r / min for 3 hours to obtain a homogeneous, non-aggregating organic carrier.

[0153] Nd 90 Cu5Al5,Y 80 Fe 20 The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0154] 70% DyO diffusion source powder, 22% propylene glycol methyl ether acetate, 4% polyester resin, 2% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed out in weight percentages, where the particle size of the TbO diffusion source powder was D50 = 2.32 μm.

[0155] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0156] The DyO diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0157] 70% Dy 80 Ni 20 The diffusion source powder, 11% propylene glycol methyl ether acetate, 13% DBE, 2% vinyl chloride resin, 1% polyester resin, 2% sodium polyacrylate, and 1% modified polyhydroxycarboxylic acid ester were weighed in weight percent, where Tb 80 Ni 20 The particle size of the diffusion source powder is D50 = 1.99 μm.

[0158] Propylene glycol methyl ether acetate, DBE, vinyl chloride resin, polyester resin, sodium polyacrylate, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 65°C and a rotation speed of 1200 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0159] Dy 80 Ni 20 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 45 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0160] 70% DyO diffusion source powder, 20% propylene glycol methyl ether acetate, 4% polyester resin, 1% polyvinylpyrrolidone, 0.5% organic bentonite, 1.5% fumed silica, and 2% BYK-SYNERGIST 2100 were weighed out in weight percentages, where the particle size of the TbO diffusion source powder was D50 = 2.35 μm.

[0161] Propylene glycol methyl ether acetate, polyester resin, polyvinylpyrrolidone, organic bentonite, fumed silica, and BYK-SYNERGIST 2100 were sequentially added to a mixer and stirred at a constant temperature of 79°C and a rotation speed of 1200 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0162] TbO metal powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 30 minutes to pre-prepare an organic paste. Then, the organic paste obtained by high-speed dispersion was transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0163] 70% Dy diffusion source powder, 11% propylene glycol, 12% methyl ether acetate, 3% polyester resin, 3% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 1.96 μm.

[0164] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 70°C and a rotation speed of 900 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0165] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0166] 10%Nd 90 Cu5Al5, 40%Dy 90 Cu5Al5, 20%Dy 80 Fe 20 The diffusion source powder, 11% propylene glycol methyl ether acetate, 11% DBE, 1% polyester resin, 1% polyester resin, 1% acrylic resin, 2% polyamide wax, 1% modified polyhydroxycarboxylic acid ester, and 2% BYK-SYNERGIST 2105 were weighed in weight percent, where Nd 90 Cu5Al5, Dy 90 Cu5Al5, Dy 80 Fe 20 The particle sizes D50 of the diffusion source powders are 2.34, 2.47, and 2.35 μm, respectively.

[0167] Propylene glycol methyl ether acetate, DBE, polyester resin, polyester resin, acrylic resin, polyamide wax, modified polyhydroxycarboxylic acid ester, and BYK-SYNERGIST 2105 were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0168] Nd 90 Cu5Al5, Dy 90 Cu5Al5, Dy 80 Fe 20 The diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 35 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0169] 70% Dy diffusion source powder, 10% propylene glycol, 12% methyl ether acetate, 3% polyester resin, 4% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 1.97 μm.

[0170] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 55°C and a rotation speed of 1000 r / min for 4.5 hours to obtain a homogeneous, non-aggregating organic carrier.

[0171] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished three times to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0172] 70% Tb-H diffusion source powder, 26% propylene glycol phenyl ether, and 4% ethyl cellulose were weighed out by weight percentage, where the particle size of the Tb-H diffusion source powder was D50 = 1.64 μm.

[0173] Propylene glycol phenyl ether and ethyl cellulose were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 600 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0174] The Tb-H diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0175] 70% Dy diffusion source powder, 15% propylene glycol, 10% methyl ether acetate, 3% polyester resin, 1% polyvinylpyrrolidone, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Dy diffusion source powder was D50 = 2.06 μm.

[0176] Propylene glycol, methyl ether acetate, polyester resin, polyvinylpyrrolidone, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 45°C and a rotation speed of 1200 r / min for 6 hours to obtain a homogeneous, non-aggregating organic carrier.

[0177] The Dy diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2300 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished twice to obtain an organic paste with a fineness of less than 5 μm. [Examples]

[0178] 70% Tb diffusion source powder, 25% DBE, 3% polyvinyl butyral, 1% polyethylene glycol, and 1% modified polyhydroxycarboxylic acid ester were weighed out in weight percentages, where the particle size of the Tb diffusion source powder was D50 = 2.08 μm.

[0179] DBE, polyvinyl butyral, polyethylene glycol, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 20 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0180] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm.

[0181] <Comparative Example 1> 60% Tb diffusion source powder, 35.7% anhydrous ethanol, 2% polyvinyl butyral, 1% polyvinylpyrrolidone, 1% polyamide wax, and 0.3% modified polyhydroxycarboxylic acid ester were weighed in weight percent, where the particle size of the Tb diffusion source powder was D50 < 3 μm.

[0182] Anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone, polyamide wax, and modified polyhydroxycarboxylic acid ester were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 900 r / min for 15 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0183] The Tb diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2000 r / min for 25 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm.

[0184] <Comparative Example 2> 80% TbNi diffusion source powder, 17.5% acetone, 1.5% polyvinyl butyral, and 1% polyethylene glycol were weighed out in weight percentages, where the particle size of the TbNi diffusion source powder was D50 < 3 μm.

[0185] Acetone, polyvinyl butyral, and polyethylene glycol were sequentially added to a mixer and stirred at a constant temperature of 25°C and a rotation speed of 1000 r / min for 20 minutes to obtain a homogeneous, non-aggregating organic carrier.

[0186] The weighed TbNi diffusion source powder and the prepared organic carrier were added to a vacuum high-speed disperser and dispersed at a rotation speed of 2200 r / min for 15 minutes to pre-prepare an organic paste. The organic paste obtained by high-speed dispersion was then transferred to a three-roller mill and polished once to obtain an organic paste with a fineness of less than 5 μm.

[0187] The volatilization profiles of the neodymium magnet screen printing organic pastes with gradient volatilization rates prepared in Examples 1-4 and the organic pastes prepared in Comparative Examples 1-2 were sequentially tested after being held at 40°C, 80°C, and 120°C for 2 hours, and the results are shown in Figures 2 and 3. As can be seen from Figure 2, the volatilization rates at 40°C for Examples 1-4 are extremely low, all less than 0.15%, ensuring storage and printing stability. When the temperature is raised to 120°C, the volatilization rate increases significantly, ensuring drying efficiency. As can be seen from Figure 3, while Comparative Examples 1-2 have very high volatilization rates at high temperatures, their volatilization rates at 40°C exceed 10% and 40%, respectively, seriously affecting the printing stability of the organic paste and making them unsuitable for continuous production.

[0188] The organic paste prepared in Example 1 was applied to the surface of a neodymium magnet by screen printing and dried at 120°C for 10 minutes. The magnet coating was then observed using a metallurgical microscope, as shown in Figure 4. The uniformity of the coating after drying was good, there were no obvious cracks or bubbles, and the bonding with the substrate was good, indicating that the volatilization rate of the organic substance during the drying process was appropriate.

[0189] The organic pastes prepared in Examples 1-8 were applied to the surface of neodymium magnets by screen printing. After drying, the neodymium magnets were heat-treated at 900°C for 5 hours, followed by tempering at 500°C for 3 hours. The measured magnet performance is shown in Table 2. The decrease in residual magnetization after diffusion was < 0.3 kGs. This indicates that the organic paste did not affect the subsequent diffusion process.

[0190] [Table 2] The embodiments of the present invention aim to protect organic pastes having a gradient volatilization rate and methods for preparing the same, and have the following effects.

[0191] The organic components are arranged in a gradient, and the strong interaction of polishing forms an organic carrier mesh structure, achieving gradient volatilization of the paste with a volatilization rate of less than 0.05% / h at room temperature and more than 1.2% / h at high temperatures of 120°C. The prepared organic paste for screen printing of rare earth permanent magnet materials has a low volatilization rate at room temperature, effectively preventing clogging and uneven printing due to the volatilization of organic solvents during printing. At high temperatures, its volatilization rate is high and the curing time is short, significantly reducing drying time, improving processing efficiency, and reducing the amount of oxygen, carbon, and other impurities that penetrate the magnet during the curing and subsequent heat treatment stages.

[0192] It should be understood that the above-described specific embodiments of the present invention are used solely to illustrate or interpret the principles of the present invention and do not limit the invention. Accordingly, modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention shall be within the scope of protection of the invention. Furthermore, the claims of the present invention are intended to cover all variations and modifications that fall within the scope and boundaries of the appended claims, or equivalent forms thereof.

Claims

1. It comprises rare earth powder, organic solvent, resin and modified polyhydroxycarboxylic acid ester, and further comprises a dispersant and / or anti-settling agent, with each component in weight percentage, Rare earth powder 50% to 90%, Organic solvents 8% to 50%, Resin 0.4% to 6%, Dispersant 0% to 5%, Anti-settlement agent 0% to 3%, An organic paste characterized by containing more than 0% and 3% or less of a modified polyhydroxycarboxylic acid ester.

2. The organic paste according to claim 1, characterized in that the rare earth powder comprises a mixture of one or two selected from a pure metal powder of a heavy rare earth element, an alloy powder containing a heavy or light rare earth element, and a heavy rare earth powder of hydrides, fluorides, and oxides containing a heavy rare earth element.

3. The pure metal powder comprises one or more of Tb, Dy, Ho, and Gd, The alloy powder is RE in weight percent ｘ M ｙ The organic paste according to claim 2, characterized in that it is composed of, where RE is one or more of Tb, Dy, Ho, Gd, Pr, Nd, La, Ce, and Y, and M is one or more of Ga, Cu, Al, Ni, and Fe, and 60 ≤ x ≤ 95 and 5 ≤ y ≤ 40.

4. The organic paste according to claim 1, characterized in that the particle size of the rare earth powder is D50 < 3 μm.

5. The organic paste according to claim 2, characterized in that the organic solvent comprises one or a mixture of two or more of propylene glycol phenyl ether, DBE, methyl isobutyl ketone, and propylene glycol methyl ether acetate.

6. The organic paste according to claim 5, characterized in that the resin comprises one or more of the following: ethylcellulose, polyvinyl butyral, acrylic resin, vinyl chloride resin, polyester resin, and polyurethane.

7. The organic paste according to claim 6, characterized in that the dispersant comprises one or more of the following: polyvinyl butyral, polyvinylpyrrolidone, sodium polyacrylate, and polyvinylamide.

8. The organic paste according to claim 7, characterized in that the anti-settling agent comprises one or more of the following: polyamide wax, polyethylene wax, organic bentonite, and fumed silica.

9. The weight percentage of each component is: Pure metal powder 65% to 75%, 10% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. 0.4% to 4% of one or more of ethylcellulose, polyvinyl butyral, and polyester resin. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in an amount of 0% to 3%. The organic paste according to claim 8, characterized in that it contains more than 0% and 2% or less of a modified polyhydroxycarboxylic acid ester.

10. The weight percentage of each component is: Alloy powder 70% to 80%, 20% to 30% of one or more of propylene glycol phenyl ether, DBE, and propylene glycol methyl ether acetate. One or more of acrylic resin, polyurethane, and polyester resin in an amount of 0.4% to 5%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in an amount of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% The organic paste according to claim 8, characterized in that it contains more than 0% and 2% or less of a modified polyhydroxycarboxylic acid ester.

11. The weight percentage of each component is: Heavy rare earth powder 60% to 80%, 10% to 30% of one or two of DBE and propylene glycol methyl ether acetate, One or more of the following: polyvinyl chloride resin, polyester resin, and polyurethane, in an amount of 0.4% to 4%. One or more of polyethylene glycol, polyvinylpyrrolidone, and polyvinylamide in an amount of 0% to 3%. One or two of polyamide waxes and polyethylene waxes, 0% to 2% The organic paste according to claim 8, characterized in that it contains more than 0% and 2% or less of a modified polyhydroxycarboxylic acid ester.

12. Weighing out rare earth powders, organic solvents, resins, and modified polyhydroxycarboxylic acid esters, as well as dispersants and / or anti-settling agents, in weight percentages, The weighed organic solvent, the resin, the modified polyhydroxycarboxylic acid ester, and the dispersant and / or the anti-settling agent are sequentially added to a mixer, stirred at a constant temperature of 20 to 70°C at a rotation speed of 600 r / min to 1200 r / min for 0.25 to 6 hours, and then cooled to room temperature to obtain an organic carrier. The organic carrier and the weighed rare earth powder are added to a vacuum high-speed disperser and dispersed at a rotation speed of 1000 r / min to 4000 r / min for 0.25 to 1 hour to obtain a crude organic paste. A method for preparing an organic paste according to any one of claims 1 to 11, characterized by comprising: transferring the coarse organic paste to a gap-adjustable three-roller mill and polishing it one to three times to obtain a fine organic paste.

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