TWI555035B - Silver paste and method for manufacturing the same - Google Patents

Description

Silver glue and its manufacturing method

The present invention relates to a metal glue, and more particularly to a silver paste and a method of manufacturing the same.

In order to increase the efficiency of the twinned solar cell, the silver electrode on the front side of the solar cell has progressed toward the direction of the thin line width. In order to reduce the line width of the silver electrode, it is necessary to increase the viscosity of the silver paste used to make the silver electrode. However, while the viscosity of the silver glue is increased, it is necessary to increase the thixotropy of the silver glue so as not to cause the battery efficiency to rise and fall.

A method of increasing the thixotropy of silver paste is to add a thixotropic agent to the silver paste. When the thixotropic agent is added to the colloid containing the metal particles, the colloid can have a higher consistency at rest, and the colloid can become a low-consistency fluid under the action of external force. At present, there are four types of thixotropic agents commonly used, including gas phase process of cerium oxide, organic bentonite, hydrogenated castor oil and polyamidamine wax. Among them, cerium oxide and organic bentonite will participate in or interfere with the reaction between silver colloid and twin crystal, so it is usually not used in silver gel of twin solar cells; hydrogenated castor oil and polyamide wax have no such disadvantages. It is often used to increase the thixotropy of silver glue.

For the preparation of silver paste for solar cells, hydrogenated castor oil and polyamide wax do not participate in or interfere with the reaction between silver gel and twin crystal, but hydrogenated castor oil and polyamide wax must be dissolved before use. In a solvent, add in the desired ratio. Due to the solubility limitation of hydrogenated castor oil and polyamidamide wax in organic solvents, in order to further increase the thixotropic coefficient of silver paste, it is necessary to increase the amount of thixotropic agent added, thus affecting the dosage of other additives, resulting in a process. The complexity is improved.

Therefore, an object of the present invention is to provide a silver paste and a method for producing the same, which is characterized in that after the colloidal kneading, the liquid polydimethyl decane is added to the gel body in a small amount of successively, thereby not only effectively improving The thixotropy of silver gel provides lubrication and is easy to measure and easy to operate.

In accordance with the above objects of the present invention, a silver paste is proposed for use in the fabrication of electrodes. The silver paste contains a conductive paste and a thixotropic agent. The conductive paste comprises a binder solution, a glass frit, an organic dispersant, a second solvent, and a silver powder. The binder solution comprises a solute and a first solvent, wherein the solute comprises ethylcellulose, and the first solvent dissolves ethylcellulose. The content of the binder solution is from 7.0 wt% to 7.7 wt%. The glass frit is mixed in the binder solution, wherein the glass frit contains lead, boron and antimony. The content of the glass frit is from 4.2% by weight to 4.4% by weight. The organic dispersant is mixed in the binder solution. The content of the organic dispersant is from 0.10% by weight to 0.35% by weight. The second solvent is mixed in the binder solution. The second solvent content is from 0 wt% to 2.0 wt%. Silver powder mixed in a binder solution, in which silver powder The content is from 84.3 wt% to 86.5 wt%. The thixotropic agent is mixed in the conductive paste, wherein the thixotropic agent comprises polydimethyl decane, and the weight of the thixotropic agent is 0.02% to 2.5% of the total weight of the conductive paste.

According to an embodiment of the invention, the thixotropic agent is pure polydimethyl decane.

According to another embodiment of the invention, the solute further comprises a lubricant.

According to still another embodiment of the present invention, the first solvent and the second solvent comprise a hexyl carbitol (HC) solvent and a butyl carbitol acetate (BCA) solvent.

According to still another embodiment of the present invention, the first solvent further comprises terpineol.

According to still another embodiment of the present invention, the first solvent comprises a dibasic acid ester solvent (DBE) or diethylene glycol monobutyl ether (BC).

According to the above object of the present invention, there is further provided a method for producing a silver paste comprising the following steps. A binder solution is prepared to dissolve the solute in a first solvent, wherein the solute comprises ethylcellulose. Prepare a conductive paste. The step of preparing the conductive paste comprises the following steps. Mixing a glass frit with an organic dispersant to form a mixture in which the content of the glass frit is from 4.2 wt% to 4.4 wt%, the content of the organic dispersant is from 0.10 wt% to 0.35 wt%, and the glass frit contains lead and boron. With 矽. A second solvent and a binder solution are added to the mixture, wherein the binder solution is present in an amount of 7.0 wt% to 7.7% by weight, and the second solvent content is 0 wt% to 2.0 wt%. Adding silver powder to the mixture mixed with the second solvent and the binder solution, wherein the content of the silver powder is 84.3 wt% to 86.5 wt%. The thixotropic agent is added to the conductive paste, wherein the thixotropic agent comprises polydimethyl decane, and the weight of the thixotropic agent is 0.02% to 2.5% of the total weight of the conductive paste.

According to an embodiment of the invention, the thixotropic agent is pure polydimethyl decane.

According to another embodiment of the present invention, the first solvent and the second solvent comprise a diethylene glycol hexyl ether (HC) solvent and diethylene glycol butyl ether acetate (BCA). In the first solvent and the second solvent, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) is 1:1.

According to still another embodiment of the present invention, after the silver powder is added to the mixture mixed with the second solvent and the binder solution, the step of preparing the conductive paste further comprises performing a plurality of kneading treatments using the three rollers.

According to still another embodiment of the present invention, the step of adding the thixotropic agent to the conductive paste comprises the following steps. Reduce the speed of the three rollers. When the conductive paste is in the three rolls, the thixotropic agent is added in portions. After the conductive agent is added to the thixotropy, a plurality of re-kneading treatments are performed using the three rollers.

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The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Flow chart of the method; [Fig. 2] shows a formula guide according to an embodiment of the present invention. Flow chart of electric glue.

In view of the fact that some thixotropic agents may participate in or interfere with the reaction between silver colloid and twin, some of them have limited solubility in organic solvents, so these conventional thixotropic agents are not unsuitable for addition to the silver used to make the electrodes of solar cells. In the glue, there is a problem of adding complicated programs. Therefore, the present invention proposes a silver paste and a method for producing the same, which uses liquid polydimethyl decane as a thixotropic agent for silver gum, which can improve the thixotropy of the silver paste, and can provide a lubricating effect and is easy to measure. It can simplify the addition of thixotropic agents.

In one embodiment of the invention, silver paste can be used to make electrodes, such as electrodes for solar cells, particularly front electrodes for solar cells. In some embodiments, the silver paste mainly comprises a conductive paste and a thixotropic agent, wherein the conductive paste is a main component and the thixotropic agent is an additive. For example, in silver paste, the weight of the thixotropic agent may be from 0.02% to 2.5% of the total weight of the conductive paste.

In some examples, the conductive paste may mainly comprise a binder solution, a glass frit, an organic dispersant, a second solvent, and silver powder. In the conductive paste, the content of the binder solution may be, for example, 7.0% by weight to 7.7% by weight. The binder solution may comprise a solute and a first solvent. Further, the binder solution may be an organic solution. For example, the solute comprises ethyl cellulose. Alternatively, the solute may contain a lubricant in addition to ethyl cellulose. In the case where the solute contains ethyl cellulose, the first solvent is a solvent which can dissolve the ethyl cellulose. The first solvent may, for example, comprise diethylene glycol hexyl ether (HC) solvent and/or diethylene glycol butyl ether acetate Ester (BCA) solvent. In an exemplary embodiment of the first solvent of some of the binder solutions, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) solvent is 1:1. However, in other examples, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) solvent may not be 1:1, but other ratios.

Alternatively, the first solvent may further comprise terpineol in addition to the diethylene glycol hexyl ether (HC) solvent and the diethylene glycol butyl ether acetate (BCA) solvent. The first solvent of the binder solution may comprise other solvents that dissolve ethylcellulose, such as an aliphatic dibasic ester mixture (DBE) and butyl carbitol (BC). Further, in some exemplary examples of the binder solution, the weight ratio of the solute to the first solvent may be 1:10.

The glass frit is mixed in the binder solution. In some examples, the glass frit may contain lead and other elements such as boron, bismuth, and the like. Further, the content of the glass frit in the conductive paste may be, for example, 4.2% by weight to 4.4% by weight. For example, before mixing the glass frit into the binder solution, the glass frit may be mixed with the organic dispersant, and the mixture of the glass frit and the organic dispersant may be mixed together in the binder solution. The content of the organic dispersant may be, for example, from 0.10% by weight to 0.35% by weight in the conductive paste. In some examples, the organic dispersant can be stearic acid.

When the mixture of the glass frit and the organic dispersant is mixed in the binder solution, the second solvent may be mixed together at the same time. The content of the second solvent in the conductive paste may be, for example, 0% by weight to 2.0% by weight. In some examples, the second solvent can comprise the same components as the first solvent. For example, the second solvent and The first solvent each contains a diethylene glycol hexyl ether (HC) solvent and a diethylene glycol butyl ether acetate (BCA) solvent. In the second solvent, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) solvent may be, for example, 1:1. In other examples, the second solvent of the diethylene glycol hexyl ether (HC) solvent and the diethylene glycol butyl ether acetate (BCA) solvent may be in other ratios. Silver powder is also mixed in the binder solution. In some examples, the content of the silver powder in the conductive paste may be, for example, 84.3 wt% to 86.5 wt%.

The thixotropic agent is mixed in the conductive paste. In the present embodiment, the thixotropic agent comprises polydimethyldecane. In some specific examples, the thixotropic agent is pure polydimethyl decane. The polydimethyl decane selected for the thixotropic agent may be of lower viscosity or higher viscosity.

Please refer to FIG. 1 , which is a flow chart of a method for manufacturing a silver paste according to an embodiment of the present invention. In the present embodiment, when manufacturing silver paste, step 100 may be performed first to prepare a binder solution. When the binder solution is prepared, the solute is mixed with the first solvent, and the solute is dissolved in the first solvent by, for example, standing and heating. The prepared binder solution can be an organic solution. In some examples, the solute comprises ethyl cellulose. In addition to ethyl cellulose, the solute may optionally contain a lubricant. In the case where the solute contains ethyl cellulose, the first solvent is a solvent which can dissolve the ethyl cellulose. The first solvent may, for example, comprise a diethylene glycol hexyl ether (HC) solvent and/or a diethylene glycol butyl ether acetate (BCA) solvent. For example, the first solvent comprises a diethylene glycol hexyl ether (HC) solvent and a diethylene glycol butyl ether acetate (BCA) solvent, and the diethylene glycol hexyl ether (HC) solvent and diethylene glycol butyl ether Acetate (BCA) solvent The weight ratio is 1:1. In other examples, the weight ratio of diethylene glycol hexyl ether (HC) solvent to diethylene glycol butyl ether acetate (BCA) solvent can be other ratios.

In addition to the diethylene glycol hexyl ether (HC) solvent and the diethylene glycol butyl ether acetate (BCA) solvent, the first solvent more selectively comprises terpineol. The first solvent of the binder solution may also comprise other solvents which dissolve ethylcellulose, such as dibasic acid ester solvent (DBE) and diethylene glycol monobutyl ether (BC). Further, in some exemplary examples, the weight ratio of the solute to the first solvent may be 1:10.

After the preparation of the binder solution is completed, step 102 is performed to prepare a conductive paste by using the binder solution as one of the components. Referring to FIG. 2 together, a flow chart of preparing a conductive adhesive according to an embodiment of the present invention is shown. As shown in FIG. 2, in some examples, when preparing the conductive paste, step 200 may be first performed to place the glass frit into a container, such as a Teflon beaker, and then the organic dispersant is added to the container, and the glass is placed. The powder is thoroughly mixed with the organic dispersant to form a mixture. In some examples, the glass frit may contain lead and other elements such as boron, antimony, and the like. Further, the content of the glass frit in the conductive paste may be, for example, 4.2% by weight to 4.4% by weight. The content of the organic dispersant in the conductive paste may be, for example, from 0.10% by weight to 0.35% by weight. In some examples, the organic dispersant can be stearic acid.

Next, step 202 is performed to add the second solvent and the binder solution to the container, thereby mixing the second solvent and the binder solution in the mixture of the glass frit and the organic dispersant. The content of the second solvent in the conductive paste may be, for example, 0% by weight to 2.0% by weight. The content of the binder solution in the conductive paste may be, for example, 7.0% by weight to 7.7% by weight. In some examples, the second solvent can be The first solvent contains the same ingredients. For example, both the second solvent and the first solvent comprise a diethylene glycol hexyl ether (HC) solvent and a diethylene glycol butyl ether acetate (BCA) solvent. In the second solvent, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) solvent may be, for example, 1:1. In other examples, the second solvent of the diethylene glycol hexyl ether (HC) solvent and the diethylene glycol butyl ether acetate (BCA) solvent may be in other ratios.

After the glass frit is completely wetted in the organic dispersant, the second solvent and the binder solution, step 204 is performed to add the silver powder to the glass frit, the organic dispersant, and the second solvent and the binder solution mixture. The content of the silver powder in the conductive paste may be, for example, from 84.3 wt% to 86.5 wt%. In some examples, the silver powder, the glass frit, the organic dispersant, the second solvent, and the binder solution may be thoroughly mixed, and then kneaded twice or three times with a three-roller to prepare a conductive paste.

After the preparation of the conductive paste is completed, as shown in FIG. 1, step 104 is performed to add the thixotropic agent to the conductive paste to complete the preparation of the silver paste. In the silver paste, the weight of the thixotropic agent may be, for example, 0.02% to 2.5% of the total weight of the conductive paste. In the present embodiment, the thixotropic agent comprises polydimethyldecane. In some specific examples, the thixotropic agent is pure polydimethyl decane. The polydimethyl decane selected for the thixotropic agent may be of lower viscosity or higher viscosity.

In some examples, when the thixotropic agent is added to the conductive paste, the rotation speed of the three rollers can be first reduced, and the thixotropic agent is added to the conductive paste in the three rollers in batches. After the thixotropic agent is added to the conductive paste, the mixture of the conductive paste and the thixotropic agent is subjected to re-kneading treatment twice or more times by using the three rollers.

By using liquid polydimethyl decane as a thixotropic agent, a thixotropic agent can be added to the conductive adhesive in a small amount of successive additions. Therefore, the embodiment can improve the thixotropy of the silver paste and provide a lubricating effect. Moreover, the metering is easy and the addition of the thixotropic agent can be simplified.

The advantages of the present invention are illustrated below using a number of examples and comparative examples. In Comparative Example 1, the preparation of the binder solution was first carried out. When preparing the binder solution, 1.60 g of ethylcellulose and 8.0 g of diethylene glycol hexyl ether (HC) solvent and 8.0 g of diethylene glycol butyl ether acetate (BCA) solvent were weighed first. The ethyl cellulose was mixed with a diethylene glycol hexyl ether (HC) solvent and a diethylene glycol butyl ether acetate (BCA) solvent, placed in a pressure-resistant glass bottle, and sealed. Next, it was heated at 90 ° C until completely ethyl cellulose was completely dissolved. An additional 4.0 g of oleic acid polyoxyethylene Sinopol 170 was added and heating was continued until all solutes were completely dissolved and then cooled. Subsequently, 5.31 g of terpineol was added and stirred until homogeneously mixed to complete the preparation of the binder solution.

Next, the preparation of the conductive paste is performed. When preparing conductive paste, first weigh 2.6g of lead powder and lead glass powder, and place the glass powder into the Teflon beaker. Further, 0.2 g of an organic dispersant was added to the Teflon beaker, and the glass frit was thoroughly mixed with the organic dispersant by hand. Next, 0.7 g of diethylene glycol hexyl ether (HC) / diethylene glycol butyl ether acetate (BCA) solvent and 4.6 g of a binder solution were added. In this solvent, the weight ratio of diethylene glycol hexyl ether (HC) to diethylene glycol butyl ether acetate (BCA) was 1:1. After the glass frit was completely wetted, 51.60 g of silver powder was added and thoroughly mixed, and then kneaded three times with a three-roller to obtain a conductive paste of Comparative Example 1, that is, the silver paste of Comparative Example 1.

In each of the examples and comparative examples, the silver gums obtained were all measured at 2 rpm and 27.0 ± 0.5 ° C using a viscometer DV-II + Pro viscometer cone/plate version supplied by Brookfield, USA.

In Comparative Example 2, the previous experimental conditions and operation of the preparation of the cement solution were substantially the same as those of the cement solution of Comparative Example 1, except that 5.31 g of pine oil containing 10% polyamine 6500 was further added. The alcohol solution was stirred until homogeneously mixed. The steps and methods for preparing the silver paste are the same as those for the silver paste of Comparative Example 1, but the binder solution is the solution of the binder of the comparative example.

In Comparative Example 3, the previous experimental conditions and operation of the preparation of the binder solution were substantially the same as those of the binder solution of Comparative Example 1, except that 5.31 g of a terpineol solution containing 10% of HCO was further added. Stir until homogeneously mixed. The steps and methods for preparing the silver paste are the same as those for the silver paste of Comparative Example 1, but the binder solution is the solution of the binder of the comparative example.

In Example 4, the binder solution was the same as Comparative Example 1. The preparation steps and methods of the conductive adhesive are the same as those of the comparative example 1, but after the preparation of the conductive adhesive is completed, the rotation speed of the three rollers is adjusted, and 0.020 g of polydimethyl decane-1 is successively added to the conductive rubber, and then three rollers are used. The silver paste of this example was obtained by mixing again three times.

In Examples 5 to 14, the binder solution was the same as Comparative Example 1. The steps and methods for preparing the conductive paste were the same as in Comparative Example 1. The thixotropic agent was added in the same manner as in Example 4 except that the weight of the polydimethyldecane-1 was changed to 0.047 g to 1.20 g.

In Example 15, the binder solution was the same as Comparative Example 1. The steps and methods for preparing the conductive paste were the same as in Comparative Example 1. The thixotropic agent was added in the same manner as in Example 4 except that the thixotropic agent was changed to add 0.020 g of polydimethylnonane-2. Among them, the molecular weight of polydimethyldecane-1 is higher than the molecular weight of polydimethyldecane-2.

In Examples 16 to 21, the binder solution was the same as Comparative Example 1. The steps and methods for preparing the conductive paste were the same as in Comparative Example 1. The method of adding the thixotropic agent was the same as in Example 15, except that the amount of polydimethyldecane-2 added was changed to 0.095 g to 1.20 g.

In Comparative Examples 22 and 23, the binder solution was the same as Comparative Example 1. The procedure and method for preparing the conductive paste were the same as in Comparative Example 1, except that 0.10 g of a diethylene glycol hexyl ether (HC)/diethylene glycol butyl ether acetate (BCA) solvent having a weight ratio of 1:1 was added. The thixotropic agent was added in the same manner as before, except that 0.095 g or 0.379 g of modified polyoxyalkylene was added.

In Comparative Examples 24 and 25, the binder solution was the same as Comparative Example 1. The procedure and method for preparing the conductive paste were the same as in Comparative Example 1, but 0.20 g of a 1:1 mixture of HC and BCA was added to each other because of a slightly higher viscosity. The thixotropic agent was added in the same manner as before, except that 0.095 g or 0.379 g of epoxy decane was added.

In Comparative Examples 26 and 27, the binder solution was the same as Comparative Example 1. The procedure and method for preparing the conductive paste were the same as in Comparative Example 1, but the viscosity was outside the range measurable by the viscometer, and 0.70 g and 1.20 g of a 1:1 mixture of HC and BCA were added. The thixotropic agent was added in the same manner as before, except that 0.095 g or 0.379 g of aminodecane was added.

In Examples 28 and 29, the preparation method of the binder solution was similar to that of Comparative Example 1, except that the weight ratio of diethylene glycol hexyl ether (HC) to diethylene glycol butyl ether acetate (BCA) in the solvent was changed to 1 : 3, and no terpineol was added. Conductive The preparation steps and methods of the gel were the same as those of Comparative Example 1, except that 1.0 g of the dispersant contained 10% of the solution of stearic acid (SA), and the solution of the binder was changed to the new solution of this example, and the amount was changed to 4.60 g. The thixotropic agent was added in the same manner as before, except that 0.40 g or 1.0 g of polydimethylnonane-1 was added.

In Examples 30 and 31, the binder solution was the same as in Example 28. The procedure and method for preparing the conductive paste were the same as those in Example 28. The thixotropic agent was added in the same manner as before, except that 0.40 g or 1.0 g of polydimethylnonane-2 was added.

Table 1 below lists the characteristics of the above comparative examples and examples.

Several examples are additionally used below to illustrate the effect of different solvents on the thixotropic effect of polydimethyl decane.

In Examples 32 and 33, the binder solution was prepared in the same manner as in Example 28 above except that the solvent was changed to a dibasic acid ester solvent (DBE), and no terpineol was added. The procedure and method for preparing the conductive paste were the same as those in Example 28. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-1 in the same manner as before.

In Examples 34 and 35, the binder solution was prepared in the same manner as in Example 32 except that the solvent was changed to diethylene glycol monobutyl ether (BC). The steps and methods for preparing the conductive paste were the same as those in Example 32. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-1 in the same manner as before.

In Examples 36 and 37, the binder solution was prepared in the same manner as in Example 32. The steps and methods for preparing the conductive paste were the same as those in Example 32. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-2 in the same manner as before.

In Examples 38 and 39, the binder solution was prepared in the same manner as in Example 32 except that the solvent was changed to diethylene glycol monobutyl ether (BC). The steps and methods for preparing the conductive paste were the same as those in Example 32. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-2 in the same manner as before.

Table 2 below lists the characteristics of Examples 32-39.

In Table 2, Examples 32, 33, 36 and 37 used a dibasic acid ester solvent (DBE) as a solvent having a flash point of 100 °C. In Examples 34, 35, 38 and 39, diethylene glycol monobutyl ether (BC) was used as a solvent, and the flash point was 99 °C. The silver gums prepared in Examples 32 to 39 were all measured at 2 rpm and 27.0 ± 0.5 ° C using a viscometer DV-II + Pro viscometer cone/plate version supplied by Brookfield, U.S.A.

As can be seen from Table 1, Comparative Example 1 is a method for preparing a silver paste to which no thixotropic agent is added, and the thixotropic coefficient is only 3.88. In Comparative Examples 2 and 3, polydecylamine (6500) and HCO (hydrogenated castor oil) were respectively added to the binder solution, and each was formulated into a silver paste of 0.15% polyamine or HCO, and the thixotropy coefficient was increased to 4.43 and 4.98.

Examples 4 to 14 were prepared according to the method of Comparative Example 1, and 0.033% to 2.50% of polydimethylnonane-1 was added, respectively. The thixotropic of these examples The coefficient is between 4.02 and 6.74, and the effect of improving the thixotropy of the silver gel is very remarkable, and the lubrication effect is improved, and the preparation operation is easy.

The silver gums of Examples 15 to 21 were prepared in the same manner as in Example 4 except that 0.033% to 2.5% of the lower molecular weight polydimethylnonane-2 was added, and the thixotropic coefficients of these examples ranged from 4.68 to 6.29. between.

In Comparative Examples 22 and 23, when silver paste was prepared in accordance with Comparative Example 1, 0.10 g and 0.20 g of a solvent were added during the preparation of the conductive paste. After the preparation was completed, 0.16% and 0.63% of the modified polyoxyalkylene were separately added. The thixotropy coefficients of Comparative Examples 22 and 23 were 3.37 and 3.54, respectively, and did not improve the thixotropy of the silver paste.

In Comparative Examples 24 and 25, when silver paste was prepared in accordance with Comparative Example 1, 0.20 g of a solvent was added during the preparation of the conductive paste. After the preparation was completed, 0.16% and 0.63% of epoxy decane were separately added. The thixotropic coefficients of Comparative Examples 24 and 25 were 3.41 and 3.55, respectively, and did not improve the thixotropy of the silver paste.

In Comparative Examples 26 and 27, when silver paste was prepared according to Comparative Example 1, 0.70 g and 1.20 g of a solvent were added during the preparation of the conductive paste. After the preparation was completed, 0.16% and 0.63% of the amino decane were separately added. The thixotropic coefficients of Comparative Examples 26 and 27 were 3.43 and 2.59, respectively, and did not improve the thixotropy of the silver paste.

The preparation method of the binder solutions of Examples 28 and 29 was as in Comparative Example 1, except that the ratio of diethylene glycol hexyl ether (HC) to diethylene glycol butyl ether acetate (BCA) was changed to 1:3, and was not added. Terpineol. The dispersant was changed to 1.0 g of a 10% stearic acid solution, and the amount of the binder solution was changed to 4.60 g. Thixotropic agent is added 0.40 g and 1.0 g of polydimethylnonane-1. The thixotropic coefficients of Examples 28 and 29 were 6.39 and 6.34, respectively.

The formulation methods of Examples 30 and 31 were as in Example 28 except that the thixotropic agent was changed to 0.40 g or 1.0 g of polydimethylnonane-2, respectively. The thixotropic coefficients of Examples 30 and 31 were 6.58 and 7.20, respectively.

Further, as is apparent from Table 2, the binder solutions of Examples 32 and 33 were prepared in the same manner as in Example 28 except that the solvent was changed to a dibasic acid ester solvent (DBE) and no terpineol was added. The conductive paste was prepared in the same manner as in Example 28. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-1, respectively, in the same manner as before. The thixotropic coefficients of Examples 32 and 33 were 5.89 and 5.86, respectively.

The conductive pastes of Examples 36 and 37 were prepared in the same manner as in Example 32 except that the thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-2, respectively, in the same manner as before. The thixotropic coefficients of Examples 36 and 37 were 6.79 and 7.88, respectively.

The binder solutions of Examples 34 and 35 were prepared in the same manner as in Example 28 except that the solvent was changed to diethylene glycol monobutyl ether (BC). The conductive paste was prepared in the same manner as in Example 28. The thixotropic agent was added with 0.40 g or 1.0 g of polydimethylnonane-1, respectively. The thixotropic coefficients of Examples 34 and 35 were 5.24 and 5.23, respectively.

The silver gums of Examples 38 and 39 were prepared in the same manner as in Example 34 except that the thixotropic agent was changed to 0.40 g or 1.0 g of polydimethylnonane-2, respectively. The thixotropic coefficients of Examples 38 and 39 were 5.44 and 5.76, respectively.

It can be seen from the above embodiments that the present invention is advantageous in that, in the preparation of the silver paste, the liquid polydimethylsilane is added to the gel body in a small amount after the colloidal mixing, thereby being effective not only effective mention The high-silver gel is thixotropy and provides lubrication, and has the advantages of easy metering and convenient operation.

While the present invention has been described above by way of example, it is not intended to be construed as a limitation of the scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

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Claims (11)

A silver paste suitable for forming an electrode, the silver paste comprising: a conductive paste comprising: a binder solution comprising a solute and a first solvent, wherein the solute comprises ethyl cellulose, and the first solvent is Dissolving the ethyl cellulose, the content of the binder solution is 7.0 wt% to 7.7% by weight; a glass frit mixed in the binder solution, wherein the glass frit contains lead, boron and antimony, the content of the glass frit Is from 4.2 wt% to 4.4 wt%; an organic dispersant mixed in the binder solution, wherein the content of the organic dispersant is from 0.10 wt% to 0.35 wt%; a second solvent is mixed in the binder solution Wherein the second solvent content is 0 wt% to 2.0 wt%; and a silver powder mixed in the binder solution, wherein the silver powder is contained in an amount of 84.3 wt% to 86.5 wt%; and a thixotropic agent is mixed in the In the conductive paste, wherein the thixotropic agent comprises liquid polydimethyl decane, and the thixotropic agent has a weight of 0.02% to 2.5% of the total weight of the conductive paste. The silver gum of claim 1, wherein the thixotropic agent is pure polydimethyl decane. The silver paste of claim 1, wherein the solute further comprises a lubricant. The silver paste of claim 1, wherein the first solvent and the second solvent comprise a diethylene glycol hexyl ether (HC) solvent and a diethylene glycol butyl ether acetate (BCA) solvent. The silver paste of claim 4, wherein the first solvent further comprises terpineol. The silver paste of claim 1, wherein the first solvent comprises a dibasic acid ester solvent (DBE) or diethylene glycol monobutyl ether (BC). A method for producing a silver paste, comprising: preparing a binder solution to dissolve a solute in a first solvent, wherein the solute comprises ethyl cellulose; preparing a conductive paste, wherein the step of preparing the conductive paste comprises: Mixing a glass frit with an organic dispersant to form a mixture, wherein the content of the glass frit is from 4.2 wt% to 4.4 wt%, the content of the organic dispersant is from 0.10 wt% to 0.35 wt%, and the glass frit comprises Lead, boron and bismuth; a second solvent and the binder solution are added to the mixture, wherein the binder solution is contained in an amount of 7.0 wt% to 7.7% by weight, and the second solvent content is 0 wt% to 2.0 wt%; And adding a silver powder to the mixture in which the second solvent and the binder solution are mixed, wherein the content of the silver powder is from 84.3 wt% to 86.5 wt%; A thixotropic agent is added to the conductive paste, wherein the thixotropic agent comprises liquid polydimethyl decane, and the thixotropic agent has a weight of 0.02% to 2.5% of the total weight of the conductive paste. The method for producing a silver paste according to claim 7, wherein the thixotropic agent is pure polydimethylsilane. The method for producing a silver paste according to claim 7, wherein the first solvent and the second solvent comprise diethylene glycol hexyl ether (HC) solvent and diethylene glycol butyl ether acetate (BCA), and In the first solvent and the second solvent, the weight ratio of the diethylene glycol hexyl ether (HC) solvent to the diethylene glycol butyl ether acetate (BCA) is 1:1. The method for producing a silver paste according to claim 7 , wherein after the silver powder is added to the mixture in which the second solvent and the binder solution are mixed, the step of preparing the conductive paste further comprises using a three-roller Multiple mixing processes. The method for manufacturing a silver paste according to claim 10, wherein the step of adding the thixotropic agent to the conductive paste comprises: reducing a rotation speed of the three rollers; and adding the conductive paste to the three rollers in batches a thixotropic agent; and after the thixotropic agent is added to the conductive paste, a plurality of re-kneading processes are performed using the three rollers.