A cleaning solution composition for copper-aluminum stack heat spreaders

Abstract

The application discloses a cleaning liquid composition for a copper-aluminum stack heat sink, which is prepared from the following raw materials: a novel polyether, an organic solvent, a dispersing agent, an emulsifier and a penetrating agent. The cleaning liquid composition prepared by the application does not contain acid and alkali components, has excellent material compatibility with copper and aluminum, and cannot cause metal discoloration. The preparation is simple, the raw materials are common, the cleaning effect is good, the material compatibility is wide, and the cleaning liquid composition is suitable for the current copper-aluminum stack heat sink manufacturing process.

Description

Technical Field

[0001] This invention belongs to the field of heat sink cleaning fluid, specifically relating to a cleaning fluid composition for copper-aluminum stacked heat sinks. Background Technology

[0002] A heatsink is a device used to dissipate heat from electronic components in electrical appliances. It is typically made of aluminum alloy, brass, or bronze, and can be in the form of plates, sheets, or multiple sheets. Regarding heatsink materials, each material has different thermal conductivity, ranked from highest to lowest: silver, copper, aluminum, and steel. However, using silver for heatsinks would be too expensive, so copper is the best option. Although aluminum is much cheaper, its thermal conductivity is obviously not as good as copper (approximately only 50% of copper's). Currently, the most commonly used heatsink materials are copper and aluminum alloys, each with its own advantages and disadvantages. Copper has good thermal conductivity, but it is expensive, difficult to process, and too heavy (many pure copper heatsinks exceed the weight limits of CPUs). It also has a relatively small heat capacity and is prone to oxidation. Pure aluminum is too soft to be used directly; only aluminum alloys provide sufficient hardness. The advantages of aluminum alloys are low price and light weight, but their thermal conductivity is much worse than copper. Some heatsinks combine the advantages of both materials, embedding a copper plate in the aluminum alloy heatsink base.

[0003] To optimize costs and increase profits, manufacturers have developed solutions that fold and press copper and aluminum sheets into various shapes of heat sinks. These are then welded to suitable heat sink base plates. This achieves heat dissipation while accelerating production and facilitating mass production. However, flux residue, primarily rosin, remains on the surface of the welded heat sinks. At high temperatures, this rosin softens and flows, potentially causing corrosion or contamination. To prevent this, the heat sinks need to be cleaned.

[0004] Currently, cleaning solutions on the market are mainly divided into water-based and solvent-based solutions. Water-based solutions have a long service life, are safe to use, and pose less harm to humans. However, most water-based solutions use strong acids and alkalis as additives, resulting in poor material compatibility and a tendency to cause corrosion and discoloration of copper and aluminum. Therefore, solvent-based cleaning solutions are more commonly used for cleaning heat sinks. Solvent-based cleaning solutions utilize the principle of "like dissolves like," dissolving contaminants in organic solvents for cleaning. However, solvent-based cleaning solutions generally have drawbacks such as high volatility, low flash point, and a tendency to cause accidents. Therefore, solvent-based cleaning solutions are not the best choice for cleaning heat sinks. Developing a water-based cleaning solution with better material compatibility for cleaning heat sinks has broad market prospects. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a cleaning fluid composition for copper-aluminum stacked heat sinks.

[0006] The present invention adopts the following technical solution: A cleaning fluid composition for copper-aluminum stacked heat sinks, comprising the following raw materials by mass fraction: Polyether 5-10% Organic solvents 60-75% Dispersant 5-10% Emulsifier 5-10% Penetrant 5-10%; The polyether has the following structure: .

[0007] Furthermore, the organic solvent is one or more of dimethyl carbonate, dibutyl maleate, dimethyl maleate, butyl tartrate, and butyl acetate.

[0008] Furthermore, the dispersant is one or more of polycarboxylate dispersants, sodium methylene bis(naphthalene) sulfonate, sodium methylene bis(naphthalene) sulfonate, and oleamide.

[0009] Furthermore, the emulsifier is one or more of the following: triethanolamine dodecylbenzenesulfonate, triisopropanolamine dodecylbenzenesulfonate, sodium dodecyl diphenyl ether disulfonate, disodium lauryl polyoxyethylene ether sulfosuccinate monoester, and ammonium alkylphenol polyoxyethylene ether sulfate.

[0010] Furthermore, the penetrant is one or more of JFC-E, JFC-2G, and JFC-SF.

[0011] Furthermore, the preparation process is as follows: First, an organic solvent is added to a stirred tank, and then polyether, dispersant, emulsifier and penetrant are added in sequence. During the feeding process, each component needs to be stirred until it is clear before the next component can be added. After all components have been added, stirring continues for 5-15 minutes to obtain the cleaning liquid composition.

[0012] Furthermore, the method of use is as follows: when using, the cleaning solution composition is diluted with DI water to 10-20wt%.

[0013] Furthermore, the method for preparing the cleaning fluid composition includes the following steps: Step 1: Add 1 mol of 4-bromoresveratrol, 2 mol of sodium iodide, 50 mol of DMAEMA, and 0.5 mol of pentamethyldiethylenetriamine sequentially to a reactor. Irradiate with UVB light for 50-70 minutes under a nitrogen atmosphere. After recrystallization from cyclohexane, C20 is obtained.14 H 11 O2-PDMAEMA-I; Step two, take the 1 mol of C obtained in step one... 14 H 11 O2-PDMAEMA-I and 0.05 mol of catalyst were added to the reactor, and dehydration was carried out at 150°C for 6 min. Under a nitrogen atmosphere, 0.5 mol of propylene oxide was added, and the temperature was maintained at 150°C and the pressure less than 0.3 MPa. When the reaction pressure dropped significantly and the temperature rose sharply, 20 mol of propylene oxide was added, and the temperature was maintained at 140-160°C and the pressure less than 0.3 MPa. This continued until the pressure in the reactor no longer decreased. The temperature was maintained for another 30 min, and the unreacted propylene oxide was removed by depressurization to obtain polyether PPO-C. 14 H 11 O2-PDMAEMA-I, wherein the catalyst is composed of K3[Co(CN)6]·6Cu(NO3)2·5H2O·0.5ZnCl2 in a molar ratio of 1:6:5:0.5.

[0014] As can be seen from the above description of the present invention, compared with the prior art, the beneficial effects of the present invention are: First, the cleaning fluid composition prepared in this application does not contain acid or alkali components, exhibits excellent material compatibility with copper and aluminum, and will not cause discoloration of the metal. Furthermore, it is simple to prepare, uses common raw materials, has good cleaning effect, and broad material compatibility, making it suitable for current copper-aluminum stacked heat sink manufacturing processes. Specifically, by adding a self-developed polyether, which is formed by the polymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA) to form a hydrophilic chain and by the polymerization of propylene oxide (PO) to form a hydrophobic tail chain, the addition of DMAEMA introduces a large number of ester groups into the polyether, which synergistically interacts with ester organic solvents to increase the emulsification performance of the flux. The addition of PO enables the polyether to have a certain defoaming ability, therefore, no additional defoamer needs to be added to this system. Secondly, by adding self-made polyether, this invention improves the cleaning performance of the cleaning solution and increases the emulsification and dispersibility of contaminants. Therefore, the heat sink can be cleaned under neutral conditions. Since the main materials of the heat sink are copper and aluminum, which are relatively active and easily corroded by alkalis, especially aluminum, as an amphoteric metal, it is afraid of both acids and alkalis. The cleaning solution disclosed in this invention is neutral, dissolves the flux with ester solvents, and further improves the cleaning effect with various additives, and does not corrode the materials. Third, the cleaning fluid composition defined in this invention requires only simple physical mixing and does not involve chemical reactions. The overall preparation process is simple and safe. Furthermore, it only needs to be diluted with DI water during use, which can be done at the customer's location. Therefore, it can be produced, sold, and transported in the form of a concentrated solution, reducing storage and transportation costs. Attached Figure Description

[0015] Figure 1 This is a synthetic route diagram for the polyether of the present invention. Detailed Implementation

[0016] The present invention will be further described below through specific embodiments.

[0017] A cleaning fluid composition for copper-aluminum stacked heat sinks, comprising the following raw materials by mass fraction: Polyether 5-10% Organic solvents 60-75% Dispersant 5-10% Emulsifier 5-10% Penetrant 5-10%.

[0018] The preparation process is as follows: First, add organic solvent to a stirred tank, and then add polyether, dispersant, emulsifier and penetrant in sequence at a speed of 100 r / min. During the feeding process, each component needs to be stirred until it is clear before adding the next component. After all components have been added, continue stirring for 5-15 min to obtain the cleaning liquid composition.

[0019] The method of use is as follows: When using, the cleaning solution composition is diluted with DI water to 10-20wt%.

[0020] The structure of polyether is as follows: .

[0021] The preparation method includes the following steps: Step 1: Add 1 mol of 4-bromoresveratrol, 2 mol of sodium iodide, 50 mol of DMAEMA, and 0.5 mol of pentamethyldiethylenetriamine sequentially to a reactor. Irradiate the reactor with UVB light at a wavelength of 315-280 nm for 50-70 minutes under a nitrogen atmosphere. After recrystallization from cyclohexane, C0 can be obtained. 14 H 11 O2-PDMAEMA-I; Step two, take the 1 mol of C obtained in step one... 14 H 11O2-PDMAEMA-I and 0.05 mol of catalyst were added to the reactor, and dehydration was carried out at 150°C for 6 min. Under a nitrogen atmosphere, 0.5 mol of propylene oxide was added, and the temperature was maintained at 150°C and the pressure less than 0.3 MPa. When the reaction pressure dropped significantly and the temperature rose sharply, 20 mol of propylene oxide was added, and the temperature was maintained at 140-160°C and the pressure less than 0.3 MPa. This continued until the pressure in the reactor no longer decreased. The temperature was maintained for another 30 min, and the unreacted propylene oxide was removed by depressurization to obtain polyether PPO-C. 14 H 11 O2-PDMAEMA-I, wherein the catalyst is composed of K3[Co(CN)6]·6Cu(NO3)2·5H2O·0.5ZnCl2 in a molar ratio of 1:6:5:0.5.

[0022] The organic solvent is one or more of dimethyl carbonate, dibutyl maleate, dimethyl maleate, butyl tartrate, and butyl acetate.

[0023] The dispersant is one or more of polycarboxylate dispersant (SN5040), sodium methylene bis(naphthalene) sulfonate (NNO), sodium methylene bis(naphthalene) sulfonate (MF), and oleamide.

[0024] The emulsifier is one or more of the following: triethanolamine dodecylbenzenesulfonate (LAS-TEA), triisopropanolamine dodecylbenzenesulfonate (LAS-IPA), sodium dodecyl diphenyl ether disulfonate (DB-45), disodium lauryl polyoxyethylene ether sulfosuccinate (MES-30), and ammonium alkylphenol polyoxyethylene ether sulfate (APESA).

[0025] The penetrant is one or more of JFC-E, JFC-2G, and JFC-SF. Example

[0026] Each embodiment and comparative example was prepared according to the parameters in Table 1. Table 1. Parameter composition of each embodiment and comparative example Cleaning test Test procedure: First, the cleaning solution was diluted according to the ratio to make the mass fraction of the original solution 20%. Then, it was added to an offline pneumatic cleaner, heated to 60°C, and the heat sink was placed in for cleaning for 10 minutes. After cleaning, it was rinsed three times with DI water at room temperature for 5 minutes each time. After rinsing, it was dried with hot air at 80°C. The cleaning effect and material compatibility were observed under a 40x magnified optical microscope. The specific results are shown in Table 2.

[0027] Table 2 Test results of each embodiment and comparative example As shown in Table 2, the cleaning solution disclosed in this invention has a good cleaning effect on heat sinks and is non-corrosive to copper and aluminum, exhibiting broad material compatibility. The comparative examples demonstrate that each component in the cleaning solution has a different function; it is the synergistic effect between these components that results in the excellent cleaning effect.

[0028] In summary, the cleaning fluid composition prepared in this application is free of acid and alkali components, exhibits excellent material compatibility with copper and aluminum, and will not cause discoloration of the metal. Furthermore, it is simple to prepare, uses common raw materials, provides good cleaning effect, and has broad material compatibility, making it suitable for current copper-aluminum stacked heat sink manufacturing processes. The addition of a self-developed polyether, formed by the polymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA) to form a hydrophilic chain and propylene oxide (PO) to form a hydrophobic tail chain, introduces a large number of ester groups into the polyether, which synergistically interacts with ester-based organic solvents, increasing the emulsification performance of the flux. The addition of PO gives the polyether a certain defoaming ability, thus eliminating the need for additional defoamers in this system.

[0029] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.

Claims

1. A cleaning fluid composition for copper-aluminum stacked heat sinks, characterized in that: Based on mass fraction, its raw material composition is as follows: Polyether 5-10% Organic solvents 60-75% Dispersant 5-10% Emulsifier 5-10% Penetrant 5-10%; The polyether has the following structure: ； The organic solvent is one or more of dimethyl carbonate, dibutyl maleate, dimethyl maleate, butyl tartrate, and butyl acetate.

2. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The dispersant is one or more of polycarboxylate dispersants, sodium methylene bis(naphthalene) sulfonate, sodium methylene bis(naphthalene) sulfonate, and oleamide.

3. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The emulsifier is one or more of the following: triethanolamine dodecylbenzenesulfonate, triisopropanolamine dodecylbenzenesulfonate, sodium dodecyl diphenyl ether disulfonate, disodium lauryl ether sulfosuccinate monoester, and ammonium alkylphenol polyoxyethylene ether sulfate.

4. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The penetrant is one or more of JFC-E, JFC-2G, and JFC-SF.

5. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The preparation process is as follows: First, add an organic solvent to a stirred tank, then add polyether, dispersant, emulsifier and penetrant in sequence. During the feeding process, each component needs to be stirred until it is clear before adding the next component. After all components have been added, continue stirring for 5-15 minutes to obtain the cleaning liquid composition.

6. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The method of use is as follows: When using, the cleaning solution composition is diluted with DI water to 10-20wt%.

7. The cleaning fluid composition for copper-aluminum stacked heat sinks according to claim 1, characterized in that: The method for preparing the cleaning fluid composition includes the following steps: Step 1: Add 1 mol of 4-bromoresveratrol, 2 mol of sodium iodide, 50 mol of DMAEMA, and 0.5 mol of pentamethyldiethylenetriamine sequentially to a reactor. Irradiate with UVB light for 50-70 minutes under a nitrogen atmosphere. After recrystallization from cyclohexane, C20 is obtained. 14 H 11 O2-PDMAEMA-I; Step two, take the 1 mol of C obtained in step one... 14 H 11 O2-PDMAEMA-I and 0.05 mol of catalyst were added to the reactor, and dehydration was carried out at 150°C for 6 min. Under a nitrogen atmosphere, 0.5 mol of propylene oxide was added, and the temperature was maintained at 150°C and the pressure less than 0.3 MPa. When the reaction pressure dropped significantly and the temperature rose sharply, 20 mol of propylene oxide was added, and the temperature was maintained at 140-160°C and the pressure less than 0.3 MPa. This continued until the pressure in the reactor no longer decreased. The temperature was maintained for another 30 min, and the unreacted propylene oxide was removed by depressurization to obtain polyether PPO-C. 14 H 11 O2-PDMAEMA-I, wherein the catalyst is composed of K3[Co(CN)6]·6Cu(NO3)2·5 H2O·0.5 ZnCl2 in a molar ratio of 1:6:5:0.5.

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