An aqueous based cleaner for use after anodizing aluminum and methods of making and using the same

Abstract

The application provides a water-based cleaning agent for aluminum anodic oxidation and a preparation method and use method thereof, and comprises pure water, an ion chelating agent, a pH regulator, a surfactant, a solubilizer and a defoaming agent; the preparation method comprises the following steps: a. dissolving the ion chelating agent in the pure water at room temperature; b. adding the pH regulator and stirring uniformly; c. sequentially adding the surfactant, the solubilizer and the defoaming agent, and stirring the mixture uniformly; and d. after standing, the water-based cleaning agent is translucent to transparent. The use method comprises the following steps: S1, a pretreatment stage; S2, a water-based cleaning agent cleaning stage; S3, a multiple cleaning and treatment stage; and S4, a final treatment stage. The application is more friendly to an aluminum alloy anodic oxidation film, can maintain the color of the aluminum alloy anodic oxidation film, and keeps the sealing quality of the oxidation film. The application has the advantages of small component raw material dosage, low cost, strong cleaning capacity, no harmful substances such as phosphorus, nitrate and borax, safety and environmental protection, and simple operation.

Description

Technical Field

[0001] This invention belongs to the field of cleaning agents, specifically a water-based cleaning agent for aluminum anodizing, its preparation method, and its usage method. Background Technology

[0002] Currently used commercial cleaning agents are primarily alkaline. During the cleaning process, especially for metals such as aluminum alloys, they can easily damage the surface oxide film, affecting its color change and even the sealing quality of the oxide film, thus reducing the quality of the anodic oxide film. Furthermore, the cleaning methods are not ideal for removing stubborn dirt or residues, particularly in small structures or pores where thorough penetration and cleaning are difficult. Additionally, after cleaning, the material is typically only passable with a #34 dyne pen; for applications requiring high levels of cleanliness, these cleaning agents and methods need further improvement.

[0003] For example, Chinese patent literature has disclosed an acidic cleaning agent, its preparation method, and a cleaning method [Chinese Patent No.: CN116083917A]. This invention discloses an acidic cleaning agent, its preparation method, and a cleaning method, which exhibit excellent cleaning effects on various types of dirt and has a wide range of applications. The acidic cleaning agent includes: an acidic agent, a first auxiliary agent, a second auxiliary agent, a corrosion inhibitor, a descaling agent, a surfactant, and a solvent.

[0004] In the above technical solutions, the cleaning effect achieved by the various components used in the acidic cleaning agent needs to be improved, the preparation method needs to be optimized, and the cleaning method is not simple enough. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a water-based cleaning agent for aluminum anodizing, its preparation method, and its usage method.

[0006] The objective of this invention can be achieved through the following technical solution: a water-based cleaning agent for aluminum anodizing, characterized in that it comprises an ion chelating agent, a pH adjuster, a surfactant, a solubilizer, an antifoaming agent, and pure water; The ion chelating agent is selected from at least one of sodium citrate, potassium citrate, sodium pentahydroxyhexanoate, sodium polyacrylate, sodium tartrate, disodium ethylenediaminetetraacetate, and sodium thiosulfate. The ion chelating agent accounts for 3% to 15% of the total weight of the water-based cleaning agent. The ion chelating agent is used to form a complex of metal ions and prevent the deposition of metal ions. The pH adjuster is selected from at least one of sodium hydroxide, sodium carbonate, sodium silicate, oxalic acid, acetic acid, citric acid, potassium oxalate, sodium acetate, sodium carbonate, tartaric acid, and sodium tartrate. The pH adjuster accounts for 0.5% to 5% of the total weight of the water-based cleaning agent. The pH of the solution is adjusted to the required range to ensure the protective effect of the cleaning agent on the product.

[0007] The surfactant is selected from at least one of polyoxyethylene fatty alcohol ether, alkylphenol polyoxyethylene ether, isomeric alcohol polyoxyethylene ether, alkyl alcohol polyoxyethylene ether, polyethylene glycol, fatty alcohol alkyl ether, and polyoxyethylene fatty alcohol ether sulfate. The surfactant accounts for 2% to 15% of the total weight of the water-based cleaning agent. The surfactant is used to reduce the surface tension of the liquid, making it easier for the water-based cleaning agent to contact the surface of the object being cleaned. The solubilizer is selected from at least one of propylene glycol, dipropylene glycol, tripropylene glycol, glycerol, glyceryl stearate, diethylene glycol, isopropanol, n-butanol, dimethyl sulfoxide, tripropylene glycol methyl ether, and tripropylene glycol butyl ether. The solubilizer accounts for 0.1% to 8% of the total weight of the water-based cleaning agent. The solubilizer enables pure water and ion chelating agents, pH adjusters, and surfactants to mix thoroughly, thereby improving the overall mixing performance of the water-based cleaning agent. The defoamer is selected from at least one of polypropylene glycol, oleic acid, dimethyl silicone oil, organosilicon, and polyether-modified polysiloxane, and the defoamer accounts for 0% to 0.5% of the total weight of the water-based cleaning agent.

[0008] In the above-mentioned water-based cleaning agent for aluminum anodizing, the pH value of the water-based cleaning agent for aluminum anodizing is 5 to 7.

[0009] A method for preparing a water-based cleaning agent for aluminum anodizing, wherein the method yields the water-based cleaning agent for aluminum anodizing as described in claim 1 or 2, and the preparation method includes the following steps: a. Dissolve the ion chelating agent in pure water at room temperature; b. Add pH adjuster and stir well; c. Add surfactant, solubilizer and defoamer in sequence, and stir the mixture until it is homogeneous; d. After standing, the water-based cleaning agent becomes translucent to transparent.

[0010] The settling time should be between 5 and 10 minutes.

[0011] A method for using a water-based cleaning agent for aluminum anodizing, wherein the method is applied to the water-based cleaning agent for aluminum anodizing as described in claim 1 or 2, and the method comprises the following steps: S1 Preprocessing Stage: Pre-soaking / pre-spraying: The product is pre-soaked or sprayed in pure water for cleaning to remove primary impurities on the surface; S2 water-based cleaning agent cleaning stage: The pretreated product is placed in a cleaning machine and cleaned using the water-based cleaning agent to remove cutting residues; the concentration of the water-based cleaning agent is 3% to 7%. S3 Multiple Cleaning and Treatment Stages: Single-stage air cutting: A single-stage air cutting process is used to remove residual moisture from the product surface; Hot water wash: Use pure water at a temperature of 45℃ to 60℃ for hot water washing for 60 to 240 seconds to further clean and purify the product surface; Secondary air cutting: A secondary air cutting process is used to remove moisture from the surface of the product after hot water washing; Cold water wash: Use room temperature pure water for cold water washing to ensure the surface is clean, for a duration of 60 to 240 seconds; Three-stage air cutting: The product surface moisture is removed after cold water washing by a three-stage air cutting process; S4 final processing stage: Cool air blower: Use room temperature air to dry the surface; Hot air drying: Use hot air at a temperature of 55℃ to 80℃ for final drying.

[0012] In the above-described method of using the water-based cleaning agent after aluminum anodizing, in step S1, the pre-immersion / pre-spraying time is 5 to 60 seconds.

[0013] In the above-mentioned method of using water-based cleaning agent after aluminum anodizing, in step S2, the cleaning machine is specifically a gantry cleaning machine or a tunnel cleaning machine, the cleaning time is 15 seconds to 60 seconds, and the cleaning temperature is 45°C to 65°C.

[0014] In the above-mentioned method of using water-based cleaning agent after aluminum anodizing, in step S3, the process of the first air cut / the second air cut / the third air cut is to blow compressed air through a flat air outlet to the product surface by a blower, so as to return the agent on the product surface to the previous chemical tank, or to make the moisture on the product surface evaporate and dry.

[0015] In the above-mentioned method of using water-based cleaning agent after aluminum anodizing, in step S4, the cold air blowing time is 5 to 60 seconds; the hot air blowing time is 120 to 300 seconds.

[0016] Compared with existing technologies, this water-based cleaning agent for aluminum anodizing, its preparation method, and its application method have the following advantages: The water-based cleaning agent used in this invention exhibits excellent cleaning performance after aluminum anodizing, passing the dyne pen test at 40# or higher, which is a significant improvement compared to the 34# dyne pen test of traditional cleaning agents and methods. At the same time, the pH value of the cleaning agent is controlled between 5 and 7, which is more friendly to the aluminum alloy anodized film, not only maintaining its color but also helping to maintain the sealing quality of the oxide film. Detailed Implementation

[0017] The following are specific embodiments of the present invention, which further describe the technical solution of the present invention, but the present invention is not limited to these embodiments. Example 1

[0018] Preparation process of water-based cleaning agent No. 1: At room temperature, 2% sodium pentahydroxyhexanoate and 1% potassium citrate were dissolved in water as ion chelating agents; 1% citric acid was added as a pH adjuster and stirred until homogeneous; the following components were added sequentially: 2% polyoxyethylene fatty alcohol ether AEO-9, 0.5% dipropylene glycol, 3.5% tripropylene glycol methyl ether and 6% isomeric alcohol polyoxyethylene ether E-1003 as surfactants; 0.5% polyethylene glycol as a solubilizer; and 0.01% silicone as a defoamer. The mixture was stirred until homogeneous and allowed to stand until the cleaning agent became translucent to transparent. Example 2

[0019] Preparation process of water-based cleaning agent No. 2: Dissolve 4% sodium pentahydroxyhexanoate and 1.5% sodium citrate as ion chelating agents in water; add 1.5% oxalic acid as a pH adjuster and stir until homogeneous; add 3% alkylphenol polyoxyethylene ether OP-40, 0.5% dipropylene glycol, 4% tripropylene glycol butyl ether and 4.5% isomeric alcohol polyoxyethylene ether E-1005 as surfactants in sequence; add 1% polyethylene glycol 600 as a solubilizer; add 0.01% organosilicon as a defoamer, stir until homogeneous, and let stand until the cleaning agent becomes translucent to transparent. Example 3

[0020] Preparation process of water-based cleaning agent No. 3: Dissolve 2% sodium pentahydroxyhexanoate and 1.5% sodium citrate as ion chelating agents in water; add 1% tartaric acid as a pH adjuster and stir well; add 2% alkylphenol polyoxyethylene ether NP-15, 0.5% diethylene glycol, 3% tripropylene glycol methyl ether and 4% isomeric alcohol polyoxyethylene ether E-1305 as surfactants in sequence; add 0.5% polyethylene glycol as a solubilizer; add 0.01% organosilicon as a defoamer, stir well, and let stand until the cleaning agent becomes translucent to transparent. Example 4

[0021] Preparation process of water-based cleaning agent No. 4: Dissolve 2% sodium pentahydroxyhexanoate and 1% potassium citrate as ion chelating agents in water; add 1.5% citric acid as a pH adjuster and stir well; add 2% polyoxyethylene fatty alcohol ether AEO-9, 1% dipropylene glycol, 3% tripropylene glycol butyl ether and 5% isomeric alcohol polyoxyethylene ether E-1003 as surfactants in sequence; add 0.5% polyethylene glycol as a solubilizer; add 0.01% organosilicon as a defoamer, stir well, and let stand until the cleaning agent becomes translucent to transparent. Example 5

[0022] Preparation process of water-based cleaning agent No. 5: Dissolve 1.5% sodium tartrate and 3% sodium pentahydroxyhexanoate as ion chelating agents in water; add 2% citric acid as a pH adjuster and stir well; add 3.5% polyoxyethylene fatty alcohol ether AEO-9, 0.5% dipropylene glycol, 2% dipropylene glycol butyl ether and 6% isomeric alcohol polyoxyethylene ether E-1005 as surfactants in sequence; add 0.5% polyethylene glycol as a solubilizer; add 0.05% organosilicon as a defoamer, stir well, and let stand until the cleaning agent becomes translucent to transparent.

[0023] The specific experimental parameters for the above water-based cleaning agents No. 1 to No. 5 are shown in the table below:

[0024] Example 6 The cleaning parameters are shown in the table below:

[0025] This cleaning agent can be prepared by adding pure water to a bath according to the specified ratio before use. The spray pressure should be adjusted according to the actual situation of the motor of different equipment.

[0026] Using the technical solution of this invention, aluminum alloy anodized products are cleaned after machining. The surface of the product is visually inspected for chemical residues, and the cleanliness is checked with dyne pens #38, #40, and #42. The color difference Lab value of the product before and after cleaning is measured and specifically represented by DE94. The closer DE94 is to 0, the smaller the color change before and after cleaning. Considering the existence of measurement error, DE94 < 0.3 is usually considered qualified, thereby determining the damage of the cleaning agent to the anodized film and its impact on the color.

[0027] The specific cleaning results based on practical tests are shown in the table below:

[0028] Comparative Example 1 uses an existing POR cleaning agent, whose main components are carbonates, silicates, and surfactants. This comparative example aims to illustrate that the cleaning agent of the present invention can achieve better quality when applied to the same product.

[0029] The above test results show that this water-based cleaning agent can be passed through a 40# dyne pen after cleaning, leaving no chemical residue, and its pH is between 5 and 7, which is friendly to aluminum alloy anodized film.

[0030] This invention provides a non-alkaline water-based aluminum alloy cleaning agent. Its components require small amounts of raw materials, are inexpensive, have strong cleaning power, and do not contain harmful substances such as phosphorus, nitrates, and borax. It is safe, environmentally friendly, and easy to operate, and can be widely used in the electronics industry, metal cleaning industry, and other fields.

[0031] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A water-based cleaning agent for aluminum anodizing, characterized in that, The water-based cleaning agent is composed of 2% sodium pentahydroxyhexanoate, 1% potassium citrate, 2% polyoxyethylene fatty alcohol ether AEO-9, 0.5% dipropylene glycol, 3.5% tripropylene glycol methyl ether, 6% isomeric alcohol polyoxyethylene ether E-1003, 0.01% organosilicon, and dissolved and mixed with pure water.

2. A water-based cleaning agent for aluminum anodizing, characterized in that, The water-based cleaning agent is composed of 4% sodium pentahydroxyhexanoate, 1.5% sodium citrate, 1.5% oxalic acid, 3% alkylphenol polyoxyethylene ether OP-40, 0.5% dipropylene glycol, 4% tripropylene glycol butyl ether, 4.5% isomeric alcohol polyoxyethylene ether E-1005, 0.01% organosilicon, and dissolved in pure water.

3. A water-based cleaning agent for aluminum anodizing, characterized in that, The water-based cleaning agent is composed of 2% sodium pentahydroxyhexanoate, 1.5% sodium citrate, 1% tartaric acid, 2% alkylphenol polyoxyethylene ether NP-15, 0.5% diethylene glycol, 3% tripropylene glycol methyl ether, 4% isomeric alcohol polyoxyethylene ether E-1305, 0.01% organosilicon, and dissolved in pure water.

4. A water-based cleaning agent for aluminum anodizing, characterized in that, The water-based cleaning agent is composed of 2% sodium pentahydroxyhexanoate, 1% potassium citrate, 1.5% citric acid, 2% polyoxyethylene fatty alcohol ether AEO-9, 1% dipropylene glycol, 3% tripropylene glycol butyl ether, 5% isomeric alcohol polyoxyethylene ether E-1003, 0.01% organosilicon, and dissolved in pure water.

5. A water-based cleaning agent for aluminum anodizing, characterized in that, The water-based cleaning agent is composed of 1.5% sodium tartrate, 3% sodium pentahydroxyhexanoate, 2% citric acid, 3.5% polyoxyethylene fatty alcohol ether AEO-9, 0.5% dipropylene glycol, 2% dipropylene glycol butyl ether, 6% isomeric alcohol polyoxyethylene ether E-1005, 0.05% organosilicon, and dissolved in pure water.

6. The water-based cleaning agent for aluminum anodizing as described in any one of claims 1-5, characterized in that, The pH value of the water-based cleaning agent after aluminum anodizing is 5-7.

7. A method for using a water-based cleaning agent after aluminum anodizing, characterized in that, The method of use applies to the water-based cleaning agent for aluminum anodizing as described in any one of claims 1-6, and the method of use includes the following steps: S1 Preprocessing Stage: Pre-soaking / pre-spraying: The product is pre-soaked or sprayed in pure water for cleaning to remove primary impurities on the surface; S2 water-based cleaning agent cleaning stage: The pretreated product is placed in a cleaning machine and cleaned using the water-based cleaning agent to remove cutting residues; the concentration of the water-based cleaning agent is 3% to 7%. S3 Multiple Cleaning and Treatment Stages: Single-stage air cutting: A single-stage air cutting process is used to remove residual moisture from the product surface; Hot water wash: Use pure water at a temperature of 45℃ to 60℃ for hot water washing for 60 to 240 seconds to further clean and purify the product surface; Secondary air cutting: A secondary air cutting process is used to remove moisture from the surface of the product after hot water washing; Cold water wash: Use room temperature pure water for cold water washing to ensure the surface is clean, for a duration of 60 to 240 seconds; Three-stage air cutting: The product surface moisture is removed after cold water washing by a three-stage air cutting process; S4 final processing stage: Cool air blower: Use room temperature air to dry the surface; Hot air drying: Use hot air at a temperature of 55℃ to 80℃ for final drying.

8. The method of using the water-based cleaning agent after aluminum anodizing as described in claim 7, characterized in that, In step S1, the pre-soaking / pre-spraying time is 5 to 60 seconds; in step S2, the cleaning machine is specifically a gantry cleaning machine or a tunnel cleaning machine, the cleaning time is 15 to 60 seconds, and the cleaning temperature is 45°C to 65°C.

9. The method of using the water-based cleaning agent after aluminum anodizing as described in claim 7, characterized in that, In step S3, the process of the first air cut, the second air cut, or the third air cut involves blowing compressed air through a flat air outlet onto the product surface using a blower.

10. The method of using the water-based cleaning agent after aluminum anodizing as described in claim 7, characterized in that, In step S4, the cold air blows for 5 to 60 seconds; the hot air blows for 120 to 300 seconds.

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