Soldering paste capable of resisting high-temperature post-welding residues and preparation method of soldering paste

Abstract

The invention discloses soldering paste resistant to high-temperature post-soldering residues and a preparation method of the soldering paste. The soldering paste comprises soldering flux and paste flux according to the weight ratio of (8-9): (1-2). The solder comprises a tin-bismuth series alloy and a titanate coupling agent modified halloysite nanotube. On the basis of the flux paste, the flux paste comprises the following raw materials in parts by weight: 35-65 parts of composite rosin; 35 to 55 parts of a solvent; 5-15 parts of tartaric acid; 5-10 parts of a thickening agent; 1-3 parts of a corrosion inhibitor; 2-4 parts of an antioxidant; and 2-3 parts of oleyl alcohol polyoxyethylene ether. The high-temperature-resistant soldering paste left after welding has the advantages of being resistant to high temperature, low in splashing and good in wettability, the welding effect is hard and firm, and welding spots are full and bright. In addition, the preparation method provided by the invention has the advantages of being simple, easy to operate and beneficial to large-scale production and application.

Description

Technical Field

[0001] The present application relates to the technical field of solder materials, and in particular to a solder paste having high temperature resistant post-weld residue and a preparation method thereof. Background Art

[0002] Solder paste is widely used in the electronics manufacturing industry and is an indispensable welding material in the SMT process. However, existing solder pastes often have problems such as not being resistant to high temperatures, being prone to spattering, and having poor wettability during high-temperature soldering. These problems seriously affect the welding quality and product performance, especially in high-energy density welding scenarios. Therefore, there is an urgent need to develop a solder paste with excellent high-temperature resistance and its corresponding preparation process to address the deficiencies in the prior art. Summary of the invention

[0003] In order to solve at least one of the above technical problems, a solder paste with high temperature resistance, low spatter and good wettability is developed. The present application provides a solder paste with high temperature resistance after welding residue and a preparation method thereof.

[0004] In a first aspect, the present application provides a solder paste having high temperature resistant post-soldering residue, the solder paste comprising solder and flux paste in a weight ratio of (8-9):(1-2); The solder comprises a tin-bismuth series alloy and a titanate coupling agent-modified halloysite nanotube; Based on the soldering solder paste, the soldering solder paste includes the following raw materials in parts by weight: 35-65 parts of compound rosin; 35-55 parts of solvent; 5-15 parts of tartaric acid; Thickener 5-10 parts; 1-3 parts of corrosion inhibitor; 2-4 parts of antioxidant; 4-7 parts of hydrogenated castor oil; 2-3 parts of oleyl alcohol polyoxyethylene ether.

[0005] By adopting the above technical scheme, the present application provides a new type of solder paste, which aims to solve the technical problems existing in the existing solder paste during high-temperature welding, such as not resistant to high temperature, easy to produce splashes, poor wettability, etc. The solder paste is composed of solder and flux paste, wherein the solder adopts a tin-bismuth series alloy, which has a high melting point and good heat resistance; at the same time, the addition of halloysite nanotubes modified by a titanate coupling agent can not only improve the fluidity of the solder paste, but also improve its wettability and heat resistance. The flux paste part contains a variety of components such as composite rosin, solvent, tartaric acid, thickener, corrosion inhibitor, antioxidant, hydrogenated castor oil and oleyl alcohol polyoxyethylene ether. These components are used in a specific proportion to effectively reduce the spatter phenomenon during welding, improve the reliability of solder joints, and maintain good welding effects under high temperature conditions. The solder paste provided by the present application can significantly improve the welding quality and product performance, is particularly suitable for high energy density welding scenarios, can effectively cope with challenges in high temperature environments, and ensure the consistency and reliability of welding. Specifically, the solder paste provided by the present application is composed of solder and flux paste, wherein the weight ratio of solder to flux paste is (8-9):(1-2). The solder part contains a tin-bismuth series alloy and halloysite nanotubes modified by a titanate coupling agent. The present application increases the stability of the solder and improves the formation of solder joints by utilizing halloysite nanotubes. In addition, the flux paste includes multiple components, among which composite rosin, as the main active substance, can remove oxides on the metal surface, promote solder flow, and improve wettability. The solvent is used to dissolve other components in the flux paste to ensure that the flux is evenly distributed in the solder paste. Tartaric acid, as an acidic substance, helps to remove the oxide layer on the metal surface and improve the welding quality.

[0006] Thickeners are used to adjust the viscosity of solder paste and prevent the solder paste from collapsing during printing or placement. Corrosion inhibitors reduce corrosion to metal substrates during welding and protect the substrate from damage. Antioxidants prevent flux from becoming ineffective due to oxidation during storage and use. Hydrogenated castor oil improves the lubricity and stability of solder paste and reduces spattering during welding. Oleyl alcohol polyoxyethylene ether, as a surfactant, can further improve the wettability of solder paste and promote good bonding between solder and metal surfaces. In summary, by optimizing the proportion of each component and selecting suitable additives, the solder paste proposed in this application can maintain good welding performance in a high temperature environment, reduce spattering, and improve wettability, thereby effectively solving the problems in the prior art.

[0007] Optionally, the composite rosin is prepared by compounding water-white rosin and polymerized rosin in a weight ratio of (3-5):1.

[0008] By adopting the above technical solution, the compound use of water-white rosin and polymerized rosin can enhance the deoxidation ability and wettability of the flux paste while maintaining good welding performance.

[0009] Optionally, the preparation method of the titanate coupling agent modified halloysite nanotubes includes the following steps: adding halloysite nanotubes to an ethanol solvent, adding a titanate coupling agent under stirring, reacting for 12-24 hours under a nitrogen atmosphere at 70-80°C, filtering, washing and drying to obtain the titanate coupling agent modified halloysite nanotubes.

[0010] By adopting the above technical scheme, the present application provides a method for preparing titanate coupling agent modified halloysite nanotubes, which aims to improve the performance problems of solder paste in the process of high temperature welding, such as not resistant to high temperature, easy to produce splashing, poor wettability, etc. Specifically, the method involves adding halloysite nanotubes to an ethanol solvent, adding a titanate coupling agent under stirring, and reacting for 12-24 hours under a nitrogen atmosphere and 70-80°C, followed by filtering, washing, drying and other steps, and finally obtaining titanate coupling agent modified halloysite nanotubes. This modified halloysite nanotube can significantly improve the wettability of the solder paste, enhance the stability of the solder paste under high temperature conditions, and reduce the splashing phenomenon during welding. By adding this modified halloysite nanotube to the solder paste, the overall performance of the solder paste can be improved, especially in high energy density welding scenarios, showing better welding quality and reliability, thereby solving the technical problems existing in the existing solder paste during high temperature welding.

[0011] Optionally, the solvent is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:(4-6).

[0012] By adopting the above technical scheme, the solvent is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:(4-6). This compound solvent has a high boiling point and good solubility, can improve the rheological properties and stability of the solder paste, and at the same time help to improve the heat resistance of the solder paste under high temperature conditions.

[0013] Optionally, the solder is selected from Sn63Pb37.

[0014] Optionally, the halloysite nanotubes account for (0.6-0.8) wt % of the solder.

[0015] Optionally, the mass ratio of the titanate coupling agent to the halloysite nanotubes is (0.2-0.3):1.

[0016] Optionally, the thickener is selected from ethylene bisstearamide.

[0017] Optionally, the corrosion inhibitor is selected from benzotriazole.

[0018] In a second aspect, the present application provides a method for preparing a solder paste with high-temperature resistant post-weld residue, the preparation method comprising the following steps: putting composite rosin, solvent, tartaric acid, oleyl alcohol polyoxyethylene ether, corrosion inhibitor, antioxidant, and hydrogenated castor oil into a container, stirring at 90-110°C until the solution becomes transparent; heating to 130-150°C, putting solder and thickener into the container, stirring for 5-7 minutes, and obtaining the solder paste with high-temperature resistant post-weld residue.

[0019] By adopting the above technical solution, the preparation method provided by the present application has the advantages of being simple, easy to operate, and conducive to large-scale production and application.

[0020] In summary, the present invention includes at least one of the following beneficial technical effects: 1. The present application provides a new type of solder paste, which aims to solve the technical problems existing in the existing solder paste during high-temperature welding, such as not being resistant to high temperatures, easy to produce splashes, and poor wettability. The solder paste is composed of solder and flux paste, wherein the solder adopts a tin-bismuth series alloy, which has a high melting point and good heat resistance; at the same time, the addition of halloysite nanotubes modified by a titanate coupling agent can not only improve the fluidity of the solder paste, but also improve its wettability and heat resistance. The flux paste part contains multiple components such as composite rosin, solvent, tartaric acid, thickener, corrosion inhibitor, antioxidant, hydrogenated castor oil and oleyl alcohol polyoxyethylene ether. These components are used in combination in a specific proportion, which can effectively reduce the splash phenomenon during welding, improve the reliability of solder joints, and maintain good welding effects under high temperature conditions. The solder paste provided by the present application can significantly improve the welding quality and product performance, is particularly suitable for high-energy density welding scenarios, can effectively cope with challenges in high-temperature environments, and ensure the consistency and reliability of welding. Specifically, the solder paste provided by the present application is composed of solder and flux paste, wherein the weight ratio of solder to flux paste is (8-9):(1-2). The solder part contains a tin-bismuth series alloy and halloysite nanotubes modified by a titanate coupling agent. The present application increases the stability of the solder and improves the formation of solder joints by utilizing halloysite nanotubes. In addition, the flux paste includes multiple components, wherein the composite rosin is used as the main active substance to remove oxides on the metal surface, promote solder flow, and improve wettability. The solvent is used to dissolve other components in the flux paste to ensure that the flux is evenly distributed in the solder paste. Tartaric acid, as an acidic substance, helps to remove the oxide layer on the metal surface and improve the welding quality. The thickener is used to adjust the viscosity of the solder paste to prevent the solder paste from collapsing during printing or placement. The corrosion inhibitor reduces the corrosion of the metal substrate during the welding process and protects the substrate from damage. The antioxidant prevents the flux from failing due to oxidation during storage and use. Hydrogenated castor oil improves the lubricity and stability of the solder paste and reduces the spatter phenomenon during welding. As a surfactant, oleyl alcohol polyoxyethylene ether can further improve the wettability of the solder paste and promote good bonding between the solder and the metal surface. In summary, by optimizing the ratio of each component and selecting appropriate additives, the solder paste proposed in this application can maintain good welding performance in a high temperature environment, reduce spatter, and improve wettability, thereby effectively solving the problems in the prior art.

[0021] 2. The present application provides a method for preparing a titanate coupling agent modified halloysite nanotube, which aims to improve the performance problems of solder paste during high-temperature welding, such as not being resistant to high temperatures, easy to produce splashes, poor wettability, etc. Specifically, the method involves adding halloysite nanotubes to an ethanol solvent, adding a titanate coupling agent under stirring, and reacting for 12-24 hours under a nitrogen atmosphere and 70-80°C, followed by filtering, washing, drying, and other steps to finally obtain a titanate coupling agent modified halloysite nanotube. This modified halloysite nanotube can significantly improve the wettability of the solder paste, enhance the stability of the solder paste under high temperature conditions, and reduce the splashing phenomenon during welding. By adding this modified halloysite nanotube to the solder paste, the overall performance of the solder paste can be improved, especially in high energy density welding scenarios, showing better welding quality and reliability, thereby solving the technical problems existing in the existing solder paste during high-temperature welding.

[0022] 3. The preparation method provided in this application is simple, easy to operate, and conducive to large-scale production and application. DETAILED DESCRIPTION

[0023] The present application is further described in detail below with reference to the embodiments.

[0024] Tartaric acid: Langfang Qianyao Technology Co., Ltd., content 99%.

[0025] Hydrogenated castor oil: CAS No. 8001-78-3, content 99%.

[0026] Oleyl alcohol polyoxyethylene ether: CAS No. 9004-98-2, content 99%.

[0027] Water-white rosin: Jining Tangyi Chemical Co., Ltd., water-white hydrogenated rosin, content 98%.

[0028] Polymerized rosin: Jining Tangyi Chemical Co., Ltd., the active ingredient content is 95%.

[0029] Tetraethylene glycol methyl ether: CAS No. 23783-42-8, Lierji Industrial (Shanghai) Co., Ltd.

[0030] Propylene glycol diacetate: Shandong Jibei New Materials Co., Ltd., CAS No. 623-84-7, content 99%.

[0031] Ethylene bisstearamide: Zhonghe Chemical (Shandong) Co., Ltd., model ZH-6598.

[0032] Benzotriazole: CAS number 95-14-7, content 99%. Specific embodiments

[0033] Example 1 This embodiment provides a solder paste with high temperature resistant post-soldering residue, the solder paste comprising solder and flux paste in a weight ratio of 9:1; The solder comprises a tin-bismuth series alloy and halloysite nanotubes modified by a titanate coupling agent (the halloysite nanotubes account for 0.7 wt % of the solder).

[0034] Based on the soldering paste, the soldering paste includes the following raw materials in parts by weight: 55 parts of compound rosin; 35 parts of solvent; 5 parts of tartaric acid; 5 parts of thickener; 1 part of corrosion inhibitor; 2 parts of antioxidant; 4 parts of hydrogenated castor oil; 2 parts of oleyl alcohol polyoxyethylene ether. The compound rosin is prepared by compounding water-white rosin and polymerized rosin in a weight ratio of 4.5:1.

[0035] Halloysite nanotubes were added to an ethanol solvent, titanate coupling agent was added under stirring, reacted for 22 hours under nitrogen atmosphere and 80°C, filtered, washed (washed with deionized water 3 times), and dried (dried at 50°C) to obtain titanate coupling agent-modified halloysite nanotubes. The mass ratio of titanate coupling agent to halloysite nanotubes was 0.25:1.

[0036] The solvent in this embodiment is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:4.

[0037] The solder in this embodiment is selected from Sn63Pb37 The antioxidant in this embodiment is butylated hydroxytoluene.

[0038] The corrosion inhibitor in this embodiment is benzotriazole.

[0039] The thickener in this embodiment is ethylene bisstearamide.

[0040] The method for preparing the residual solder paste after high temperature resistant welding in this embodiment comprises the following steps: Put composite rosin, solvent, tartaric acid, oleyl alcohol polyoxyethylene ether, corrosion inhibitor, antioxidant and hydrogenated castor oil into a container, stir at 100°C until the solution becomes transparent; raise the temperature to 145°C, put solder and thickener into the container, stir for 7 minutes, and obtain high temperature resistant solder paste.

[0041] Example 2 The difference between this embodiment and embodiment 1 is that, when preparing a solder paste with high temperature resistant post-weld residue, the total weight of the composite rosin is 55 parts; wherein the weight ratio of water-white rosin to polymerized rosin is 3:1.

[0042] Example 3 The difference between this embodiment and embodiment 1 is that, when preparing a solder paste with high temperature resistant post-weld residue, the total weight of the composite rosin is 55 parts, wherein the weight ratio of water-white rosin to polymerized rosin is 4:1.

[0043] Example 4 The difference between this embodiment and embodiment 1 is that, when preparing a solder paste with high temperature resistant post-weld residue, the total weight of the composite rosin is 55 parts, wherein the weight ratio of water-white rosin to polymerized rosin is 5:1.

[0044] Comparative Examples 1-3 Comparative Example 1 The difference between this comparative example and Example 1 is that, in preparing a solder paste having high temperature resistant post-weld residue, an equal amount of water-white rosin is used instead of polymerized rosin.

[0045] Comparative Example 2 The difference between this comparative example and Example 1 is that when preparing a solder paste having high temperature resistant post-weld residue, an equal amount of polymerized rosin is used to replace water-white rosin.

[0046] Comparative Example 3 The difference between this comparative example and Example 1 is that, when preparing a solder paste having high temperature resistant post-weld residue, an equal amount of halloysite nanotubes is added to replace the titanate coupling agent-modified halloysite nanotubes.

[0047] Experimental testing: 1. Expansion rate: The expansion rate of solder paste was measured according to SJ / T11389-2019 "Method for Lead-free Soldering Flux". The test results are shown in Table 1.

[0048] 2. Tin balls: The tin balls after soldering with solder paste were measured according to IPCJSTD005. The test results are shown in Table 1.

[0049] 3. Wettability: The wettability of solder paste after welding was measured according to IPCJSTD005. The test results are shown in Table 1.

[0050] Table 1 - Experimental test results of Examples 1-4 and Comparative Examples 1-3 Example Expansion rate (%) Tin beads (grade) Wettability (grade) Example 1 87.9 2 2 Example 2 84.4 2 2 Example 3 86.2 2 2 Example 4 85.7 2 2 Comparative Example 1 80.3 3 3 Comparative Example 2 82.1 3 3 Comparative Example 3 63.2 3 4 Result analysis: The difference between Examples 2-4 and Example 1 is that when preparing a solder paste with high temperature resistant post-weld residue, the weight ratio of water-white rosin and polymerized rosin is different. Combined with the experimental test data in Table 1, it can be seen that when the weight ratio of water-white rosin and polymerized rosin is 4.5:1, the comprehensive performance of the solder paste with high temperature resistant post-weld residue is better. The difference between Comparative Example 1 and Example 1 is that when preparing a solder paste with high temperature resistant post-weld residue, an equal amount of water-white rosin is used instead of polymerized rosin. The difference between Comparative Example 2 and Example 1 is that when preparing a solder paste with high temperature resistant post-weld residue, an equal amount of polymerized rosin is used instead of water-white rosin. Combined with the experimental test data in Table 1, it can be seen that when polymerized rosin and water-white rosin are used at the same time, it has a significant effect on improving the wetting performance and expansion rate of the solder paste. The difference between Comparative Example 3 and Example 1 is that when preparing a solder paste with high temperature resistant post-weld residue, an equal amount of halloysite nanotubes is added instead of the titanate coupling agent modified halloysite nanotubes. Combined with the experimental test data in Table 1, it can be seen that when halloysite nanotubes are used instead of the titanate coupling agent modified halloysite nanotubes, the expansion rate, wettability and tin bead generation of the solder paste will be affected. The reason may be that the modified halloysite nanotubes can significantly improve the wettability and expansion rate of the solder paste and reduce the generation of tin beads. This is because the modification improves the interface compatibility between the halloysite nanotubes and the solder powder, thereby improving the overall performance of the solder paste.

[0051] In summary, through the comparison of the examples and the comparative examples, it can be concluded that a specific ratio of composite rosin and modified halloysite nanotubes has a significant effect on improving the comprehensive performance of solder paste. These findings provide important guidance for the development of solder paste with high temperature resistance, low spatter and good wettability.

[0052] Embodiment 5-6 Example 5 The difference between this embodiment and embodiment 1 is that, when preparing a solder paste having high temperature resistant post-weld residue, the weight fractions of some components are changed. The difference is shown in Table 2.

[0053] Table 2 - Differences between Example 5-6 and Example 1 Ingredients (portions) Example 1 Example 5 Example 6 Compound rosin 35 58 65 Solvents 35 47 55 tartaric acid 5 12 15 Thickener 5 8 10 Corrosion Inhibitor 1 2 3 Antioxidants 2 3.5 4 Oleyl alcohol polyoxyethylene ether 2 2.7 3 Hydrogenated Castor Oil 4 6 7 The experimental test results of Examples 5-6 are shown in Table 3.

[0054] Table 3 - Experimental test results of Examples 5-6 Example Expansion rate (%) Tin beads (grade) Wettability (grade) Example 1 87.9 2 2 Example 5 89.2 1 1 Example 6 88.3 2 2 Result analysis: The difference between Example 5-6 and Example 1 is that when preparing a solder paste with high temperature resistant post-weld residue, the weight proportions of some components are different. Combined with the experimental test results in Table 3, it can be seen that the comprehensive performance of the solder paste with high temperature resistant post-weld residue prepared by Example 5 is better.

[0055] Embodiment 7-8 Example 7 The difference between this embodiment and embodiment 5 is that the solvent in this embodiment is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:5.5.

[0056] Example 8 The difference between this embodiment and embodiment 5 is that the solvent in this embodiment is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:6.

[0057] The experimental test results of Examples 7-8 are shown in Table 4.

[0058] Table 4 - Experimental test results of Examples 7-8 Example Expansion rate (%) Tin beads (grade) Wettability (grade) Example 5 89.2 1 1 Example 7 91.2 1 1 Example 8 90.6 1 1 Result analysis: The difference between Example 7-8 and Example 5 is that when preparing solder paste with high temperature resistant post-weld residue, the weight ratio of tetraethylene glycol methyl ether and propylene glycol diacetate is different. Combined with the experimental test data in Table 4, it can be seen that when the weight ratio of tetraethylene glycol methyl ether and propylene glycol diacetate is 5:5.5, the comprehensive performance of the prepared solder paste is better.

[0059] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A solder paste with high temperature resistant post-weld residue, characterized in that: The solder paste comprises solder and flux paste in a weight ratio of (8-9):(1-2); The solder comprises a tin-bismuth series alloy and a titanate coupling agent-modified halloysite nanotube; Based on the soldering solder paste, the soldering solder paste includes the following raw materials in parts by weight: 35-65 parts of compound rosin; 35-55 parts of solvent; Tartaric acid 5-15 parts; Thickener 5-10 parts; 1-3 parts of corrosion inhibitor; 2-4 parts of antioxidant; 4-7 parts of hydrogenated castor oil; 2-3 parts of oleyl alcohol polyoxyethylene ether.

2. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The composite rosin is prepared by compounding water-white rosin and polymerized rosin in a weight ratio of (3-5):

1.

3. The solder paste with high temperature resistant post-weld residue according to claim 1, wherein the preparation method of the titanate coupling agent modified halloysite nanotubes comprises the following steps: The halloysite nanotubes are added to an ethanol solvent, and a titanate coupling agent is added under stirring, and the reaction is carried out for 12-24 hours at 70-80° C. in a nitrogen atmosphere, and the titanate coupling agent-modified halloysite nanotubes are obtained by filtering, washing and drying.

4. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The solvent is prepared by compounding tetraethylene glycol methyl ether and propylene glycol diacetate in a weight ratio of 5:(4-6).

5. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The solder is selected from Sn63Pb37.

6. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The halloysite nanotubes account for (0.6-0.8) wt % of the solder.

7. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The mass ratio of the titanate coupling agent to the halloysite nanotubes is (0.2-0.3):

1.

8. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The thickener is selected from ethylene bisstearamide.

9. The solder paste with high temperature resistant post-weld residue according to claim 1, characterized in that: The corrosion inhibitor is selected from benzotriazole.

10. A method for preparing the solder paste with high temperature resistant post-welding residue according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: adding composite rosin, solvent, tartaric acid, oleyl alcohol polyoxyethylene ether, corrosion inhibitor, antioxidant and hydrogenated castor oil into a container, stirring at 90-110° C. until the solution becomes transparent; heating to 130-150° C., adding solder and thickener into the container, stirring for 5-7 minutes, and obtaining the high-temperature resistant solder paste residual after welding.