CN114023511B - Method for preparing high-temperature electronic paste based on organic phosphorus salt - Google Patents

Abstract

The invention discloses a method for preparing high-temperature electronic slurry based on organic phosphorus salts. The present invention uses n-hexyl-3-methylimidazole hexafluorophosphate (NHIHP) to surface modify the conductive phase powder to improve the dispersion and the bonding strength of the conductive powder; the applied high-temperature electronic slurry includes in parts by mass The following composition: 7 to 12 parts of new slurry carrier, 78 to 90 parts of conductive powder with different particle sizes, and 3-5 parts of glass phase. The present invention uses the surface combination of NHIHP and the conductive phase to make the slurry particles evenly distributed. It can not only enhance the bonding strength between the conductive particles and form a dense film, but also has environmentally friendly ingredients. It can not only enhance the conductive effect of the slurry, but also improve the performance of the slurry. Performance of high temperature electronic pastes.

Description

A method for preparing high-temperature electronic slurry based on organophosphorus salts

Technical field

The invention relates to a modification method, in particular to a method for preparing high-temperature electronic slurry based on organic phosphorus salts.

Background technique

High-temperature electronic paste is widely used in the industrial production of electronic components and integrated circuits. It is usually composed of a conductive phase, a glass phase and an organic solvent. It can be printed to form conductive nanowires; after high-temperature sintering, the organic phase and surfactant After pyrolysis and volatilization, the glass powder melts on the substrate and bonds with the silver powder to form a conductive dense film. During this process, the distribution of conductive particles and the contact resistance between particles have a profound impact on the properties of the slurry, affecting the formation of dense conductive films of the slurry and its conductive properties. There are many problems that need to be solved urgently in high-temperature electronic slurries, such as: there are too many pollutants in the organic solvent, which is not friendly to the environment; the conductive phase particles have large surface energy, poor dispersion, and are easy to agglomerate; the surface morphology of the conductive phase particles is not modified due to The gaps are large, the distribution is uneven, the conductive film has many gaps, and the connections are not tight, causing unnecessary energy consumption and other problems. Various shortcomings have always hindered the industrialization process of high-temperature electronic pastes.

CN108666002A discloses a metallic glass-ceramic powder, including TeO ₂ : 10-50wt%, TiO ₂ : 15-70wt%, ZnO: 2-10wt%, SiO ₂ : 1-15wt% and Li ₂ O: 5-20wt %, the glass phase has high viscosity at high temperature, is not easy to flow, has high surface tension, and has precise lines during printing, but has poor adhesion effect on the conductive phase, conductive powder is easy to agglomerate, has large connection gaps, and has poor conductive effect.

CN202011529639.0 discloses a method that uses toluenesulfonyl hydrazide to adhere to the surface of conductive particles, and hydrolyzes to produce microscopic bubbles to evenly disperse them. In the invention, the dispersibility of the slurry is improved, but the microbubbles increase the contact resistance between conductive particles. , the slurry performance is low.

_{CN202011253070 . _ _ _ _ _} :1～5%. Glass and slurry have good dispersion, and the dispersion of the conductive phase is improved. However, the addition of additives such as toluene and xylene causes serious environmental pollution.

Therefore, providing an environmentally friendly modification technology method that enables the conductive phase to have good dispersion performance and the conductive phase powder to adhere tightly is an urgent problem that those skilled in the art need to solve. This patent uses 1-n-hexyl-3-methylimidazole hexafluorophosphate as a surface modification agent to modify the surface of conductive phase powder, improve dispersion and bonding strength, and produce environmentally friendly and high-performance high-temperature electronic slurry.

Contents of the invention

In view of this, the purpose of the present invention is to provide a method for preparing high-temperature electronic slurry based on organic phosphorus salts in order to solve the problems existing in the prior art. In particular, it provides an environmentally friendly method that enables good dispersion performance of the conductive phase and adhesion of the conductive phase powder. Compact modification technology approach and its application in high-temperature electronic slurries.

In order to achieve the above objects, the technical solutions of the present invention are as follows:

A surface modification method based on organophosphorus salts, including the following steps:

The conductive powder is uniformly dispersed in a mixed solution of ethanol and ether, the organic phosphorus salt is added to the solution, stirred uniformly at a constant temperature of 45°C for 30 minutes, and centrifuged and vacuum dried to obtain a pretreated conductive phase.

The organic phosphorus salt is 1-n-hexyl-3-methylimidazole hexafluorophosphate.

Another object of the present invention is to provide a method for preparing high-temperature electronic slurry.

In order to achieve the above objects, the present invention adopts the following technical solutions:

A method for preparing high-temperature electronic slurry, the method specifically includes the following steps:

(1) Surface pretreatment of conductive phase powder: Evenly disperse the conductive phase powder in a mixed solution of ethanol and ether, add 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then add hypophosphorous acid sodium, stir uniformly at a constant temperature of 45°C for 30 minutes, and centrifuge and vacuum dry to obtain pretreated conductive powder.

(2) Preparation of glass powder: glass components include in mass percentage: Bi ₂ O ₃ : 67-78 wt%; B ₂ O ₃ : 5-11 wt%; SiO ₂ : 0-3 wt%; ZnO: 8-15 wt%; InO: 1-7wt%; CuO: 0-2wt%; SnO: 0-2wt%; Put the glass components into the sintering furnace in proportion, raise the temperature to 1100°C and bake at a constant temperature for 2 hours, then take it out and pour it into deionized water to cool. After quenching and ball milling, glass powder with a particle size of 5-40 μm is obtained;

(3) Prepare organic carrier: the mass ratio of the slurry carrier is organic solvent, reducing agent, dispersant, coupling agent, thickener and 1-n-hexyl-3-methylimidazole hexafluorophosphate in proportion Under the conditions of 45-65℃, stir evenly for 15-30 minutes at a rotation speed of 150-250r/min to obtain a uniformly mixed slurry carrier.

(4) Prepare high-temperature electronic slurry: Stir and mix the obtained pretreated conductive powder, glass powder and organic carrier with a disperser to obtain the high-temperature electronic slurry.

Preferably, in step (1), the conductive phase powder is at least one of silver powder and silver-coated copper powder, and the conductive phase powder and 1-n-hexyl-3-methylimidazole hexafluorophosphate are by mass Mix at ratio (28-32):1.

Further, the proportioned conductive phase powder is surface-pretreated silver powder or silver-coated copper powder, the small particle size powder is a granular powder with an average particle size of 0.5-1 μm, and the large particle size powder is an average particle size. A flaky powder of 7-10 μm; the average particle size of the granular conductive phase powder is 0.5 μm, 0.7 μm, 0.9 μm or 1 μm, and the average particle size of the flaky conductive phase powder is 7 μm, 8 μm, 9 μm or 10 μm; small particles The mass ratio of small particle size powder to large particle size powder is M _small : M _large = (0.6-1): 2, where the mass ratio can be 0.6:2, 0.7:2, 0.8:2, 0.9:2, 1: 2.

Furthermore, the mass ratio of ethanol to ether in the mixed solution of ethanol and ether is (3-5):1, the centrifugal speed is 6000-10000rpm, and the time is 5-10 minutes.

Preferably, in step (2), the glass phase powder is glass powder prepared based on Bi-B-Zn.

Preferably, in step (3), the organic solvent is high temperature resistant resin or terpineol, the reducing agent is at least one of citric acid, ascorbic acid, and formic acid, the dispersing agent is polyvinyl alcohol, and the The coupling agent is a silane coupling agent, and the thickening agent is ethyl cellulose.

Further, the mass ratio of organic solvent, reducing agent, dispersant, coupling agent, thickener and 1-n-hexyl-3-methylimidazole hexafluorophosphate in the slurry carrier is (65-85): (5-15):(1-8):(3-10):(2-10):(0-2).

Preferably, in step (4), the mass ratio of slurry carrier, conductive phase powder and glass phase powder in the high-temperature electronic slurry is (7-12): (78-90): (3-5).

Further, the rotating speed of the disperser in the stirring step is 9000-15000 rpm, and the processing time is 15-30 minutes.

It can be seen from the above technical solutions that compared with the existing technology, the present invention provides a method for preparing high-temperature electronic slurry based on organic phosphorus salts, which has the following excellent effects:

The present invention uses 1-n-hexyl-3-methylimidazole hexafluorophosphate to surface modify the conductive phase powder to improve the dispersion and the bonding strength of the conductive powder; the applied high-temperature electronic slurry includes the following in terms of mass parts Composition: 7-12 parts of slurry carrier, 78-90 parts of conductive powder with different particle sizes, 3-5 parts of glass phase. The present invention uses the surface combination of 1-n-hexyl-3-methylimidazole hexafluorophosphate and the conductive phase to uniformly distribute the slurry particles. It can not only enhance the bonding strength between the conductive particles and form a dense film, but also has environmentally friendly ingredients. , which can not only enhance the conductive effect of the slurry, but also improve the performance of high-temperature electronic slurry.

Detailed ways

The technical solutions in the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

The embodiment of the present invention discloses a method for preparing high-temperature electronic slurry based on 1-n-hexyl-3-methylimidazole hexafluorophosphate, and more specifically discloses a method for preparing high-temperature electronic slurry.

In order to better understand the present invention, the present invention will be further described in detail through the following examples, but they should not be understood as limitations of the present invention. For some non-essential improvements and adjustments made by those skilled in the art based on the above-mentioned content of the invention, It is also considered to fall within the protection scope of the present invention.

Below, the technical solution of the present invention will be further described with reference to specific embodiments.

Example 1:

A method for preparing high-temperature electronic slurry based on organophosphorus salts, specifically including the following steps:

Step 1: Surface pretreatment of conductive phase powder: Disperse 85g of the proportioned conductive phase powder in 510 mL of ethanol and ether mixed solution, add 1g of 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then Add 4g of sodium hypophosphite, stir evenly for 30 minutes at a constant temperature of 45°C, centrifuge at 10,000 rpm for 15 minutes, and dry in a vacuum to obtain pretreated conductive phase powder;

Step 2: Prepare glass powder: Take out each glass component in proportion and put it into a sintering and holding furnace for firing. Then use deionized water to cool and quench the glass. After ball milling, the glass powder is obtained;

Step 3: Preparation of organic carrier: The mass ratio of the slurry carrier is terpineol, citric acid, polyvinyl alcohol, silane coupling agent, ethyl cellulose and 1-n-hexyl-3-methylimidazolium The fluorophosphate is stirred evenly for 20 minutes at a speed of 150 rpm at 50°C in a mass ratio of 76:8:6:5:5:0 to obtain a uniformly mixed slurry carrier;

Step 4: Preparation of slurry: Disperse the obtained pretreated conductive powder, glass phase powder, and organic carrier with a disperser at a rotation speed of 8000 rpm for 20 minutes in a mass ratio of 85:5:10 to obtain a uniform and environmentally friendly high-temperature electronic slurry. .

Example 2:

A method for preparing high-temperature electronic slurry based on organophosphorus salts, specifically including the following steps:

Step 1: Surface pretreatment of conductive phase powder: Disperse 85g of the proportioned conductive phase powder in 510 mL of ethanol and ether mixed solution, add 3g of 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then Add 4g of sodium hypophosphite, stir evenly for 30 minutes at a constant temperature of 45°C, centrifuge at 10,000 rpm for 15 minutes, and dry in a vacuum to obtain pretreated conductive phase powder;

Step 2: Prepare glass powder: Take out each glass component in proportion and put it into a sintering and holding furnace for firing. Then use deionized water to cool and quench the glass. After ball milling, the glass powder is obtained;

Step 3: Preparation of organic carrier: The mass ratio of the slurry carrier is terpineol, citric acid, polyvinyl alcohol, silane coupling agent, ethyl cellulose and 1-n-hexyl-3-methylimidazolium The fluorophosphate is stirred evenly for 20 minutes at a speed of 150 rpm at 50°C in a mass ratio of 76:8:6:5:5:0 to obtain a uniformly mixed slurry carrier.

Step 4: Preparation of slurry: Disperse the obtained pretreated conductive powder, glass phase powder, and organic carrier with a disperser at a rotation speed of 10,000 rpm for 20 minutes in a mass ratio of 85:5:10 to obtain a uniform and environmentally friendly high-temperature electronic slurry. .

Example 3:

A method for preparing high-temperature electronic slurry based on organophosphorus salts, specifically including the following steps:

Step 1: Surface pretreatment of conductive phase powder: Disperse 85g of the proportioned conductive phase powder in 510mL of ethanol and ether mixed solution, add 5g of 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then Add 4g of sodium hypophosphite, stir evenly for 30 minutes at a constant temperature of 45°C, centrifuge at 10,000 rpm for 15 minutes, and dry in a vacuum to obtain pretreated conductive phase powder;

Step 2: Prepare glass powder: Take out each glass component in proportion and put it into a sintering and holding furnace for firing. Then use deionized water to cool and quench the glass. After ball milling, the glass powder is obtained;

Step 3: Preparation of organic carrier: The mass ratio of the slurry carrier is terpineol, citric acid, polyvinyl alcohol, silane coupling agent, ethyl cellulose and 1-n-hexyl-3-methylimidazolium The fluorophosphate is stirred evenly for 20 minutes at a speed of 150 rpm at 50°C in a mass ratio of 76:8:6:5:5:0 to obtain a uniformly mixed slurry carrier;

Step 4: Preparation of slurry: Disperse the obtained pretreated conductive powder, glass phase powder, and organic carrier with a disperser at a rotation speed of 10,000 rpm for 20 minutes in a mass ratio of 85:5:10 to obtain a uniform and environmentally friendly high-temperature electronic slurry. .

Example 4:

A method for preparing high-temperature electronic slurry based on organophosphorus salts, specifically including the following steps:

Step 1: Surface pretreatment of conductive phase powder: Disperse 85g of the proportioned conductive phase powder in 510 mL of ethanol and ether mixed solution, add 3g of 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then Add 4g of sodium hypophosphite, stir evenly for 30 minutes at a constant temperature of 45°C, centrifuge at 10,000 rpm for 15 minutes, and dry in a vacuum to obtain pretreated conductive phase powder; Step 2: Prepare glass powder: Take out each glass component in proportion and put it into a sintering and holding furnace for sintering. After preparation, use deionized water to cool and quench, and the obtained glass is ball-milled to obtain glass powder;

Step 3: Preparation of organic carrier: The mass ratio of the slurry carrier is terpineol, citric acid, polyvinyl alcohol, silane coupling agent, ethyl cellulose and 1-n-hexyl-3-methylimidazolium The fluorophosphate is stirred evenly for 20 minutes at a speed of 150 rpm at 50°C in a mass ratio of 76:8:6:5:5:2 to obtain a uniformly mixed slurry carrier.

Step 4: Preparation of slurry: Disperse the obtained pretreated conductive powder, glass phase powder, and organic carrier with a disperser at a rotation speed of 10,000 rpm for 20 minutes in a mass ratio of 85:5:10 to obtain a uniform and environmentally friendly high-temperature electronic slurry. .

Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other.

The content of the present invention is not limited to the content of the above-mentioned embodiments, and the combination of one or several embodiments can also achieve the purpose of the present invention.

In order to further verify the excellent effect of the present invention, the inventor also conducted the following experiments:

Comparative example 1:

This comparative example provides a high-temperature electronic slurry, which is consistent with Example 2 except that 1-n-hexyl-3-methylimidazole hexafluorophosphate is not added in the surface pretreatment of the conductive phase powder in step 1.

Comparative example 2:

This comparative example provides a high-temperature electronic slurry, which is consistent with Example 4 except that 1-n-hexyl-3-methylimidazole hexafluorophosphate is not added in the surface pretreatment of the conductive phase powder in step 1.

Comparative example 3

High temperature electronic paste is common in a certain market.

Performance Testing:

The conductive pastes provided in Examples 1-4 and Comparative Examples 1-3 were used to form films:

A semi-automatic precision printing machine was used with a 325-mesh screen and a film thickness of 30um. After printing, the film was cured at 400°C for 10 minutes and then cured at 700°C for 20 minutes to conduct resistance testing and adhesion strength testing.

The slurry is printed on the flexible substrate, and after curing for 10 minutes, it is bent 200 times, and the resistivity after bending is tested.

The result is as follows:

The above results show that the products provided by the present invention have better electrical conductivity; comparing Examples 1-4 and Comparative Examples 1-3, it can be found that the present invention uses 1-n-hexyl-3-methylimidazole hexafluorophosphate surface modification technology The use of this method makes the conductive powder more dispersed and the conductive film denser. Its reducing properties make the gaps in the conductive film of the slurry smaller and improve the performance of the slurry.

The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A method for preparing high-temperature electronic slurry based on organophosphorus salts, characterized in that the method specifically includes the following steps: (1) Surface pretreatment of conductive phase powder: Evenly disperse the conductive phase powder in a mixed solution of ethanol and ether, add 1-n-hexyl-3-methylimidazole hexafluorophosphate to the solution, and then add hypophosphorous acid Sodium, stir uniformly at a constant temperature of 45°C for 30 minutes, centrifuge and vacuum dry to obtain pretreated conductive powder; (2) Preparation of glass powder: take the glass components and put them into a sintering furnace for firing, then quench with deionized water and ball mill to obtain glass powder; (3) Preparation of organic carrier: Combine organic solvent, reducing agent, dispersant, coupling agent, thickener and 1-n-hexyl-3-methylimidazole hexafluorophosphate at 45~65℃ at 150 -250 r/min, stir evenly for 15-30 minutes to obtain a uniformly mixed slurry carrier; (4) Preparing high-temperature electronic slurry: Stir and mix the obtained pretreated conductive powder, glass powder and organic carrier with a disperser to obtain the high-temperature electronic slurry. 2. A method for preparing high-temperature electronic slurry based on organic phosphate salts according to claim 1, characterized in that in step (1), the conductive phase powder is at least one of silver powder and silver-coated copper powder. , the conductive phase powder and 1-n-hexyl-3-methylimidazole hexafluorophosphate are mixed at a mass ratio of (28-32): 1. 3. A method for preparing high-temperature electronic slurry based on organic phosphate salts according to claim 1 or 2, characterized in that the conductive phase powder is surface-pretreated silver powder or silver-coated copper powder, and its small particles Small-size powder is a granular powder with an average particle size of 0.5-1 μm, and large-size powder is a flaky powder with an average particle size of 7-10 μm; the average particle size of the granular conductive phase powder is 0.5 μm, 0.7 μm, 0.9 μm. Or 1 μm, the average particle size of the flaky conductive phase powder is 7 μm, 8 μm, 9 μm or 10 μm; the mass ratio of small particle size powder to large particle size powder is M _small : M _large = (0.6-1): 2. 4. A method for preparing high-temperature electronic slurry based on organophosphorus salts according to claim 3, characterized in that the mass ratio of ethanol and ether in the mixed solution of ethanol and ether is (3-5): 1, The centrifugal speed is 6000-10000 rpm and the centrifugal speed is 5-10 minutes. 5. A method for preparing high-temperature electronic slurry based on organophosphorus salts according to claim 1, characterized in that in step (2), the glass component includes, in mass percentage: Bi ₂ O ₃ : 67-78 wt%; B ₂ O ₃ : 5-11 wt%; SiO ₂ : 0-3 wt%; ZnO: 8-15 wt%; InO: 1-7 wt%; CuO: 0 -2wt%; SnO: 0-2 wt%, and the glass powder is a glass powder prepared based on Bi-B-Zn. 6. A method for preparing high-temperature electronic slurry based on organic phosphorus salts according to claim 1 or 5, characterized in that the sintering temperature in step (2) is 1100°C and the constant temperature sintering time is 2 hours. 7. A method for preparing high-temperature electronic slurry based on organophosphorus salts according to claim 1, characterized in that in step (3), the organic solvent is a high-temperature resistant resin or terpineol, and the reducing agent It is at least one of citric acid, ascorbic acid, and formic acid, the dispersant is polyvinyl alcohol, the coupling agent is a silane coupling agent, and the thickening agent is ethyl cellulose. 8. A method for preparing high-temperature electronic slurry based on organic phosphate salts according to claim 6, characterized in that in the slurry carrier, organic solvents, reducing agents, dispersants, coupling agents, thickeners and The mass ratio of 1-n-hexyl-3-methylimidazole hexafluorophosphate is (65-85): (5-15): (1-8): (3-10): (2-10): (0 -2). 9. A method for preparing high-temperature electronic slurry based on organic phosphate salts according to claim 1, characterized in that in step (4), the high-temperature electronic slurry contains a slurry carrier, conductive phase powder and glass phase. The mass ratio of powder is (7-12): (78-90): (3-5). 10. A method for preparing high-temperature electronic slurry based on organic phosphate salts according to claim 1 or 8, characterized in that the rotating speed of the disperser is 9000-15000 rpm, and the processing time is 15-30 min.