WO2019061341A1

WO2019061341A1 - White aluminum part and preparation method therefor

Info

Publication number: WO2019061341A1
Application number: PCT/CN2017/104541
Authority: WO
Inventors: 吴元凯; 王飞; 熊宜松
Original assignee: 欧朋达科技(深圳)有限公司
Priority date: 2017-09-29
Filing date: 2017-09-29
Publication date: 2019-04-04
Also published as: CN108138351A

Abstract

Disclosed is a method for preparing a white aluminum part, which method comprises the following steps: carrying out a surface micro-etching treatment on an aluminum part (S01); carrying out an electro-coloring treatment on the aluminum part (S02), wherein a white coloring slurry is electrolyzed onto a surface of the aluminum part, the surface of which has undergone a micro-etching treatment; and carrying out a dehydration treatment and a drying treatment on a white film layer (S03).

Description

White aluminum piece and preparation method thereof

Technical field

[0001] The present invention belongs to the technical field of materials, and more particularly to a white aluminum member and a method for preparing the same.

Background technique

[0002] With the development of electronic products in the world and other requirements in the development of lightweight materials such as aviation, products are extending in a light and thin direction. As a result, the demand for lightweight materials is increasing, and the associated mechanical performance requirements for the corresponding materials are also higher. Among them, aluminum and its alloys are widely used due to their light weight and good mechanical properties.

[0003] Consumers are increasingly demanding the thinness and mechanical performance of products. With the trend of consumer personalized consumption development, consumption and the color of products also have diverse requirements. Among them, white is one of the colors that the public likes, but the white realization of the current aluminum metal products is generally painted with metal or plastic into white, which is not scratch-resistant and has no good texture.

[0004] For example, the current aluminum alloy mobile phone casing with relatively large market consumption, the aluminum alloy anodized mobile phone casing is currently the mainstream product on the market, that is, aluminum and its alloys in the corresponding electrolyte and specific process conditions. Next, a process of forming an oxide film on the aluminum product (anode) due to the applied current. However, the current aluminum anodizing dye has no white color, that is, the current anodizing treatment cannot form a white oxide film layer, so the white film layer cannot be realized by the conventional anode + dyeing.

[0005] In order to achieve white, such as the realization of white aluminum casing, it is now mostly achieved by painting.

However, the film thickness of the painted product is at least 20-30μηι, and its texture is completely the same as that of the resin, thus reducing the metal texture of the aluminum product, such as the aluminum mobile phone case.

technical problem

[0006] The object of the present invention is to overcome the above-mentioned deficiencies of the prior art, and to provide a white aluminum member and a preparation method thereof, to solve the problem that the metal texture of the prior aluminum component is poor, or the anodization cannot form a white film layer. Technical problem.

Problem solution

Technical solution In order to achieve the above object, an aspect of the present invention provides a method for preparing a white aluminum member, comprising the following steps:

[0008] The aluminum member is subjected to surface micro-etching treatment, and the surface of the aluminum member is etched to form micropores;

[0009] etching the aluminum member formed with micropores to perform an electro-coloring treatment to form a white film layer on the surface of the aluminum member;

[0010] performing a dehydration treatment and a drying treatment on the white film layer;

[0011] wherein, the electrochromic treated electrolyte is a white colored paste comprising water, paint and a white paste; and the mass ratio of the water, paint and white paste is (12-13) : ( 2-3) : (1-1.2).

[0012] In another aspect, the invention provides a white aluminum piece. The white aluminum member includes an aluminum member body, and the surface of the aluminum member body is etched with a plurality of micropores, at least in the micropores, a white film layer is electrically colored; wherein the white coloring paste forming the white film layer is formed Including water, paint, and white stock; and the mass ratio of the water, paint, and white stock is (12-13): (2-3): (1-1.2).

Advantageous effects of the invention

Beneficial effect

[0013] Compared with the prior art, the method for preparing the white aluminum member described above uses an electro-coloring method to electrolyze the white colored paste onto the surface of the surface of the aluminum-etched aluminum member to form a high-light white film layer on the surface of the aluminum member. The same effect is achieved by reducing the thickness of the film layer, so that the aluminum member has a good metal texture, and the white film layer has a high bonding strength with the aluminum surface. In addition, the preparation method is easy to control, the product quality is stable, the production efficiency is effectively improved, and the production cost is reduced.

[0014] The white aluminum member electrically colores the white film layer on the surface on which the micropores are etched on the surface, thereby imparting a high gloss whiteness to the film layer, and the film layer has a high bonding strength with the surface of the aluminum member. In addition, the white film layer is thin, imparting a good metallic texture to the white aluminum member, effectively improving the quality of the aluminum member and improving its market competitiveness.

Brief description of the drawing

DRAWINGS

1 is a flow chart of a method for preparing a white aluminum member of the present invention;

2 is a flow chart of a method for surface micro-etching of an aluminum member of the present invention.

Embodiments of the invention [0017] In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail below with reference to the embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0018] The mass percentages of the components mentioned in the description of the embodiments of the present invention may not only indicate the proportional relationship between the masses of the components, but also the specific content of each component, and therefore, as long as it is according to the present invention The content of each component of the pharmaceutical composition in the specification of the examples is enlarged or reduced in proportion to the scope of the specification of the embodiment of the present invention. Specifically, the mass described in the specification of the embodiment of the present invention may be a mass unit well known in the art such as μ _§ , mg , g , kg , etc., and may of course be regarded as a mass percentage.

[0019] Embodiments of the present invention provide a method of preparing a white aluminum member. The flow chart of the method for preparing the white aluminum piece is shown in Fig. 1, which comprises the following steps:

[0020] Step S01. Surface micro-etching treatment of the aluminum member: the aluminum member is subjected to surface micro-etching treatment, and the micro-hole is formed by etching on the surface of the aluminum member;

[0021] Step S02. Electro-coloring treatment of the aluminum member: the aluminum member formed by etching the micropores is subjected to electro-coloring treatment to form a white film layer on the surface of the aluminum member;

[0022] Step S03: Dehydrating and drying the white film layer.

[0023] Specifically, the surface of the aluminum member is micro-etched in the above step S01, so that the surface of the aluminum member has micropores, so that the white coating formed by the electro-coloring in the above step S02 can be combined with the surface of the aluminum member with high strength. One.

[0024] In an embodiment, the method of performing surface micro-etching treatment on the aluminum member in this step can be processed according to the process flow shown in FIG. 2. The method for performing surface micro-etching treatment on the aluminum member comprises the following steps:

[0025] Step S011: the aluminum parts are sequentially subjected to degreasing treatment, alkali etching treatment and pretreatment of neutralization treatment;

[0026] Step S012: performing an anodic electrolysis treatment on the surface of the pretreated aluminum member to form micropores on the surface of the aluminum member;

[0027] Step S013: performing reaming treatment on the aluminum member subjected to the anodic electrolysis treatment.

[0028] The aluminum member in the above step S011 may be a cast or an intermediate member, etc., and the aluminum member may be a pure aluminum member or an aluminum alloy member. In a particular embodiment, the aluminum piece can be, but not exclusively, an aluminum phone case.

[0029] Since the aluminum parts are attached to the surface during the previous molding, polishing, storage and handling process, some oil and dust adhere to the surface.

Therefore, the aluminum member in the step S011 can be effectively removed from the surface of the aluminum member after being degreased. Oil and dust, etc., can also ensure that the surface of the aluminum part can be fully infiltrated by the subsequent treatment liquid, and has been uniformly treated. Therefore, in an embodiment, the aluminum material is degreased in the step S011 by placing the aluminum member in a degreasing liquid for processing. Specifically, the degreasing liquid can be a conventional degreasing liquid

For example, if the neutral (PH8) degreasing powder HX-800 is dissolved in pure water, the concentration is 55g/l-65g/l. After heating to 55 ° C, the aluminum parts were immersed therein for 3 minutes.

[0030] Before the aluminum member is degreased, the aluminum member is polished and mirrored. After the aluminum parts are degreased, the aluminum parts are cleaned with pure water, such as level 2 water washing, before the alkali etching treatment.

[0031] The alkali etching treatment in the step S011 is effective to remove the oxide layer on the surface of the aluminum member to expose the essential metal of the aluminum member.

In one embodiment, the alkali etching treatment is performed by using a base of the film and a pure water to prepare a concentration of 40 g/L to 50 g/L. After the temperature is raised to 60 °C, the product is immersed in the solution for 2 minutes to fully react the surface oxide of the aluminum part with the solution to expose the essential metal of the aluminum part.

[0032] After the aluminum piece is subjected to alkali etching treatment, before the neutralization treatment, the aluminum piece is subjected to pure water cleaning, such as level 2 washing.

[0033] The neutralization treatment in this step S011 is effective to remove the alkali remaining on the surface of the aluminum member. In one embodiment, the neutralization solution of the neutralization treatment is prepared using 68% nitric acid plus purified water. Formulated at a concentration of 100 g/L - 120 g/L. The purpose is to remove the alkaline solution on the surface of the aluminum part. After the aluminum parts are subjected to neutralization treatment, the aluminum parts are subjected to pure water washing, such as a 2-stage water washing to remove the neutralizing solution.

[0034] The pretreatment of the aluminum member is performed to effectively remove impurities and an oxide layer on the surface of the aluminum member, thereby improving the cleanliness of the surface of the aluminum member, so that the aluminum material is exposed to the bare metal, and the anode of the aluminum member is electrolytically treated in step S012. The micropores on the surface of the aluminum piece are enlarged to be fully prepared, and the uniformity of the micropores of the aluminum piece in step S012 is improved.

[0035] The anodic electrolysis treatment in the step S012 is to cause the aluminum on the surface of the aluminum member to be corroded to leave micropores, so that the surface of the aluminum member forms an uneven rough surface having pits. The micro-etching treatment is performed by subjecting the pretreated aluminum member to an anodic electrolytic electrolytic solution for etching treatment.

[0036] In an embodiment, the electrolyte electrolytically treated in the step S012 comprises: 280-300 g/L sulfuric acid, preferably 290-300 g/L, specifically 280; 1.0-2 g/L oxalic acid, preferably 1.0-1.5g/L, specifically 1.5g/L.

[0037] In a further embodiment, the process conditions of the anodic electrolysis treatment are: temperature: 18-20 ° C, preferably 20 ° C; daytime: 18-20 min, preferably 20 min; voltage: 18-20 V, preferably 20V. Due to the anode electrolysis The temperature is controlled at 18-20 ° C. Therefore, during the anodic electrolysis process, an intelligent cooling circulation system is arranged to ensure that the temperature of the electrolyte for processing the crucible is constant. In a preferred embodiment, the voltage is gradually increased from 0V to 18-20V, preferably 20V. Specifically, the voltage is uniformly increased to the voltage range within 1 minute. By gradually increasing the voltage, the rate of etching the micropores is lowered, and the micropores are further uniformly and aligned by slowing down the surface of the aluminum member to a micropore speed.

Further, during the anodic electrolysis treatment, the concentration of the aluminum ion in the electrolytic solution is controlled to be 4-7 g/L.

[0039] By controlling the process conditions of the anodic electrolysis process, the aluminum on the surface of the aluminum member becomes aluminum ions and enters the solution, thereby leaving micropores on the surface of the aluminum member, that is, forming a layer of micropores on the surface of the aluminum member. The rough surface, and the micropores formed by etching are uniform, such as forming a microporous layer structure such as a honeycomb, and the pore diameter is moderate. Thus, the bonding strength of the surface of the aluminum member, such as the bonding strength with the white film layer, is effectively increased. As an embodiment, the pores formed by the anodic electrolysis treatment have a pore diameter of 30 to 35 nm. In order to effectively enter the white colorant particles during the subsequent electro-coloring process, the adhesion is enhanced, and the color is not easily faded, so that the workpiece maintains a long-lasting appearance.

[0040] After the anodic electrolysis treatment is completed, the aluminum member is subjected to microporous washing treatment to remove impurities and electrolytes in the porous layer of the aluminum member, such as anodic electrolytic treatment of the electrolyte, so as to implement the next step and avoid the next step. The effect of the process implementation has an adverse effect. Therefore, in one embodiment, the microporous washing treatment may be a 2-stage pure water treatment or a 2-stage ultrasonic pure water treatment. Of course, it can also be a washing liquid commonly used in aluminum electrolysis, so that the residue in the microporous layer of the residual aluminum member is sufficiently removed, thereby providing an effective guarantee for the implementation and implementation of the subsequent process steps.

[0041] The reaming treatment in the above step S013 is to enlarge the pore diameter in the porous layer of the cleaned aluminum member, so that the aluminum member has a suitable aperture as required for the subsequent white film layer process, thereby enhancing the white film aluminum layer. The bonding strength of the surface of the piece. In an embodiment, the reaming process is performed by placing the aluminum piece after the microporous washing process in a reaming treatment liquid to perform a hole expanding micro-etching process. In a specific embodiment, the expanding The pore treatment liquid comprises 95% of an organic solvent, 3% of an inorganic solvent, and 1.8% of an active agent, wherein the organic solvent is at least one of triethanolamine and styrene, and the inorganic solvent is not only ethylenediamine. The active agent is at least one of, but not exclusively, a lignosulfonate or an alkylsulfonate. In a further embodiment, the process conditions of the reaming treatment are: temperature: 25-30 ° C, daytime: 3-3.5 min, pH: 8-10. Through the control of the reaming treatment liquid and the reaming treatment process conditions, the hole in the porous layer on the surface of the aluminum piece is ensured. The homogeneity of the diameter of the diameter can appropriately enlarge the pore size, for example, the pore diameter of the micropores is 50-70 nm, so that the white color paste particles can be effectively entered during the subsequent electro-coloring treatment, thereby enhancing the adhesion, It is easy to fade, leaving the workpiece with a long-lasting appearance.

In a further embodiment, after the reaming treatment in the step S013, a step of performing a microporous washing treatment on the aluminum member is further included to remove residues in the micropores, such as a reaming treatment liquid or the like. In a specific embodiment, the microporous washing treatment can be directly carried out by referring to the microporous washing treatment process steps and process conditions in step S013.

[0043] In a preferred embodiment, after the micropore washing treatment after the reaming treatment in step S013, before performing the electro-coloring treatment in step SO2, further comprising surface treating the aluminum member, the surface treatment The aluminum member after the micro-etching treatment is placed in a MICRO CLEAN F4 solution for cleaning. In one embodiment, the MICRO CLEAN F4 solution comprises a MICRO CLEAN F4 cleaning agent and water, and the ratio of the MICRO CLEAN F4 cleaning agent to water is (1-1.5): (5-6), and the The pH of the MICRO CLEAN F4 solution is 8.5-9. By the surface treatment, the impurities in the residual micropores can be removed without cleaning the micropores, and the MICRO CLEAN F4 can be adhered to the surface of the micropores of the aluminum member, and after the aluminum member is subjected to the electrocoloring treatment in the following step S02, The bonding strength of the white film layer to the surface of the aluminum member, particularly the microporous surface, can be enhanced, thereby enhancing the bonding force of the white film layer. Among them, MICRO CLEAN F4 is anhydrous sodium sulfate 5 parts: isopropanol 3 parts: ethylene glycol butyl ether 1 part: glycidyl ester 2 parts by mass of a mixture.

[0044] The electro-coloring process in the above step S02 is that the aluminum member processed in the step S01 is used as a cathode, and the lead plate is built in the tank as an anode, and the electro-coloring treatment is performed under the action of direct current, so that the white colored paste acts on the direct current. The deposition is carried out into the micropores of the surface of the aluminum member which is microetched in step S01.

[0045] In one embodiment, the electrochromic treated electrolyte is a white colored paste comprising water, paint, and a white paste; and the mass ratio of the water, paint, and white paste is (12-13): (2-3) : (1-1.2) , the specific can be 12:2:1.

[0046] In a specific embodiment, the paint includes the following components by mass:

[0047] hydroxyethyl acrylate 5 ± 0.2 parts

[0048] butyl acrylate 3 ± 0.2 parts

[0049] glycidyl fat 2.5 ± 0.1 parts [0050] 1 ± 0.1 parts of lactic acid

[0051] Propylene glycol phenyl ether 0.8 ± 0.1 parts.

[0052] In another specific embodiment, the white slurry comprises the following components by mass:

[0053] White toner 3 ± 0.3 parts, organic solvent 5 ± 1 part.

In another embodiment, the conditions of the electro-coloring treatment are: a direct current voltage of 125V-135V, an electrolyte temperature of 25-27 ° C, and an electrolyte pH of 7.0-7.5. Since the temperature of the electro-coloring treatment is controlled at 25-27 ° C, an intelligent cooling circulation system can be disposed in the anodic electrolysis process as in the above step S012 to ensure that the electro-dyed electrolytic solution of the crucible is also processed. That is, the temperature of the bath is constant

[0055] The condition of the above electro-coloring treatment causes the white colored paste to be decomposed into a cation-yang electrolyte under the action of a direct current voltage, so that under the action of the voltage, the electrolyte moves to be adsorbed in the micropores on the surface of the aluminum member and forms a white film. Floor. Moreover, the white film layer is provided with high luminosity and has mirror characteristics. The same effect reduces the thickness of the white film layer, so that the aluminum member has a good metal texture, and the white film layer has a high bonding strength with the aluminum surface.

Further, under the conditions of the above-described electro-coloring treatment, the thickness of the white film layer formed by the electro-coloring treatment can be adjusted by controlling the turn of the electro-coloring treatment. In one embodiment, the turn of the electrochromic treatment is 2 min. Or by controlling the electric coloring treatment, the thickness of the white film layer formed is 5-8 μm.

[0057] In the above step S03, the formed white film layer is subjected to dehydration treatment to dehydrate the white film layer to improve the stability of the film layer. In one embodiment, the dehydration treatment is to immerse the aluminum member subjected to the electro-coloring treatment into a dehydration solution; wherein the dehydration solution comprises a surfactant and water, and the quality of the surfactant and water The ratio is (1-2): 100, specifically as 1:100. Wherein the surfactant is, but not limited to, at least one of absolute ethanol and glycerin. Through the control of the above-described dehydration treatment conditions, the aluminum member including the white film layer realizes slow-drawing dehydration. After dehydration treatment, the aluminum parts are washed before the drying process, such as pure water treatment, to remove the residual dehydration liquid, to avoid adverse effects on the performance of the white film layer such as white stability. This dehydration treatment can be carried out at normal temperature.

[0058] The drying process in the step S03 includes a pre-baking process and a post-baking process. The pre-baking treatment temperature is 75-82 ° C, specifically 80 ° C; the daytime is 9-l lmin, specifically 10 min. The post-baking treatment temperature is 178-182 ° C, specifically 180 ° C; the daytime is 38-41 min, specifically 40 min. [0059] By the dehydration treatment and the drying treatment in the above step S03, the sealing treatment of the white film layer is realized, thereby improving the mechanical strength of the white film layer, such as improving the scratch resistance and the bonding strength, and simultaneously improving the white film layer. White stability.

It can be seen from the above that the white coloring paste of the above-mentioned white aluminum member is electrolyzed to the surface of the surface of the surface of the aluminum material which is subjected to micro-etching by an electro-coloring method, so that a high-light white film layer is formed on the surface of the aluminum member. The same effect reduces the thickness of the film layer, so that the aluminum piece has a good metal texture, and the white film layer has a high bonding strength with the surface of the aluminum piece. In addition, the preparation method is easy to control, the product quality is stable, the production efficiency is effectively improved, and the production cost is reduced.

In addition, in order to improve the stability of the processing in the above steps, the conductivity of the control water is preferably controlled within the range of 1.5-2 u _S /cm.

Accordingly, based on the above-described method for preparing a white aluminum member, the embodiment of the present invention further provides a white aluminum member. The white aluminum member includes an aluminum member body, and the surface of the aluminum member body is etched with a plurality of micro holes

A white film layer is electrically colored at least in the micropores.

[0063] wherein, the aluminum piece body is as described above in the method for preparing a white aluminum piece, the surface micro-etched aluminum piece

. Thus, the surface of the aluminum body is etched to form micropores. In an embodiment, the pore size of the micropores is 50-7

Specifically, the plurality of micropores are distributed in a honeycomb shape on the surface of the aluminum member.

The white coloring paste of the above-mentioned white film layer formed by electrochromic coloring is as described in the above-described method for producing a white aluminum member, which includes water, paint, and a white slurry. And the mass ratio of the water, the paint and the white slurry is (12-1)

3) : (2-3) : ( 1-1.2) , the specific can be 12:2: 1.

[0065] In a specific embodiment, the paint includes the following components by mass:

[0066] hydroxyethyl acrylate 5 ± 0.2 parts

[0067] butyl acrylate 3 ± 0.2 parts

[0068] glycidyl grease 2.5±0.1 parts

[0069] Lactic acid 1 ± 0.1 parts

[0070] propylene glycol phenyl ether 0.8 ± 0.1 parts.

[0071] In another specific embodiment, the white slurry comprises the following parts by mass:

[0072] White toner 3±0.3 parts, organic solvent 5±1 parts.

[0073] In another embodiment, the conditions of the electro-coloring process are: DC voltage is 125-130V, electrolyte The temperature is controlled to 25-27 ° C and the pH of the electrolyte is 7.0-7.5. Since the temperature of the electro-coloring process is controlled at 25-27

°C, therefore, in the anodic electrolysis process, an intelligent cooling circulation system can be disposed as in the above step S012 to ensure that the temperature of the electrolyte for the electrochromic treatment of the crucible is constant.

The conditions of the above electro-coloring treatment are such that the white colored paste is at least in the micropores of the surface of the aluminum member and forms a white film layer. Moreover, the white film layer is provided with high luminosity and has mirror characteristics. The same effect reduces the thickness of the white film layer, so that the aluminum piece has a good metal texture, and the white film layer has a high bonding strength with the surface of the aluminum piece. Further, under the conditions of the above-described electro-coloring treatment, the thickness of the white film layer formed by the electro-coloring treatment can be controlled by controlling the turn of the electro-coloring treatment. In one embodiment, the turn of the electrochromic treatment is 2 min. Or by controlling the electric coloring treatment, the thickness of the white film layer formed is 5 μm. Therefore, the above-mentioned white aluminum member is electrically colored with a white film layer on the surface on which the micropores are etched, thereby imparting a high gloss to the film layer, and the film layer has a high bonding strength with the surface of the aluminum member. In addition, the white film layer is thin, imparting a good metallic texture to the white aluminum member, effectively improving the quality of the aluminum member and improving its market competitiveness.

[0075] In addition, the white aluminum member may be any one of a mobile phone case, a computer case, an air conditioner frame and a casing, and a TV case.

[0076] The present invention will now be further described in detail by taking a specific white aluminum member and its preparation method as an example.

Embodiment 1

[0078] A white aluminum member and a preparation method thereof, comprising the following process steps:

[0079] S11: Degreasing the mirror-treated aluminum piece - 2 grade water washing - alkali etching treatment - 2 grade water washing - neutralization treatment

To remove the impurity layer on the surface of the aluminum member, including the oxide layer, so that the aluminum member is exposed to the intrinsic metal; wherein, [0080] degreasing treatment: the degreasing powder is a neutral (ΡΗ8) degreasing powder ΗΧ-800, and The pure aqueous phase is dissolved, and the concentration is 55 g/lg/l. After heating to 55 ° C, the workpiece is immersed therein for 3 minutes;

[0081] Alkali etching treatment: using a base of alkali and pure water, the concentration is 40g / Lg / l, after heating to 60 ° C, the aluminum parts are soaked in the solution for 2 minutes, so that the aluminum surface oxide Fully react with the solution to expose the essential metal;

[0082] Neutralization treatment: The neutralization solution is prepared by using 68% nitric acid plus pure water at a concentration of 100 g/L g/1.

. The purpose is to remove the alkaline solution of the product surface and prepare for the entry into the anode electrolysis cell;

[0083] S12: performing surface micro-etching treatment on the aluminum member pretreated in step S11, and etching the surface of the aluminum member Microporous; wherein, the micro-etching process is: anodic electrolysis treatment - 2 grade water washing - reaming treatment - 2 grade water washing;

[0084] The conditions of the anodic electrolysis treatment are as follows:

[0085] Electrolyte: sulfuric acid 300g / L, oxalic acid 1.5g / L, the rest is pure water;

[0086] The anodic electrolysis process parameters: temperature 18-20 ° C, daytime 20 min, voltage 20 V, the voltage is raised to 20 V at a constant rate within 1 minute;

[0087] The concentration of aluminum ions in the electrolyte during the electrochemical anode treatment is controlled to be 4-7 g/L.

[0088] The conditions for the reaming treatment are as follows:

[0089] Reaming treatment liquid: organic solvent 95%, inorganic solvent 3%, active agent 1.8%;

[0090] Process parameters of the reaming treatment: temperature: 25 ° C; daytime: 3 min; pH: 8;

[0091] S13: cleaning the aluminum component microetched in step S12 in a MICRO CLEAN F4 solution to clean impurities in the micropores and improve adhesion in the micropores; wherein, the MICRO CLEAN F4 solution is The ratio of MICRO CLEAN F4 cleaning agent to pure water is 1: 5, and the pH control range is 8.5-9;

[0092] S14: the aluminum member subjected to the cleaning process of the aluminum member in step S13 is subjected to an electro-coloring treatment to form a white film layer on the surface of the aluminum member;

[0093] The conditions of the electro-coloring treatment are as follows:

[0094] Electrolyte: The mass ratio of water, paint and white slurry is 12:2:1; wherein the paint is formulated as (hydroxyethyl acrylate) 5: (butyl acrylate) 3: (shrinkage) Glycerol) 2.5: (lactic acid) 1 : (propylene glycol phenyl ether) 0.8; white paste formulation (white toner) 3: (organic solvent) 5;

[0095] Process parameters of the electro-coloring treatment: a direct current voltage of 130 V, an electrolyte temperature of 25 ° C, an electrolyte pH of 7.0, and a daytime of 2 minutes;

[0096] S15: performing the dehydration treatment-pre-baking treatment-post-drying treatment of the aluminum member treated in step S14;

Dehydration treatment All dehydration solutions include a surfactant and water, and the mass ratio of the surfactant to water is 1:100. Wherein the surfactant is an organic solvent;

[0098] The temperature of the pre-baking treatment is 80 ° C; the daytime is lOmin;

[0099] The temperature of the post-baking treatment was 180 ° C; the daytime was 40 min.

Example 2 [0101] Repeat the example 1 step, where S12

After the medium voltage operation was changed to 20V, the electrolysis was reduced to 18 minutes, and other conditions were unchanged.

Example 3

[0103] Repeat Example 1 to increase the electrolytic coloring time in S14 to 2 minutes and 30 seconds, and the other conditions are unchanged [0104] Comparative Example 1

The aluminum member of Example 1 was anodized with a conventional anodizing method.

Comparative Example 2

[0107] The aluminum member in Example 1 was formed by using a conventional paint.

[0108] Related performance test:

The white aluminum members prepared in the above Examples 1-3 and the aluminum members provided in the comparative examples were subjected to the relevant performance tests in Table 1 below, and the test results are shown in Table 1.

Table 1

[]

[] [Table 1]

As can be seen from Table 1, the white aluminum member provided by the embodiment of the present invention is white and has a specular high gloss white color. The thickness of the same film layer is low, and the metal texture is strong. Due to the presence of micropores, the white film layer has a high bonding strength with the surface of the aluminum piece. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

Claim

[Claim 1] A method for preparing a white aluminum member, comprising the steps of:

The aluminum member is subjected to a surface micro-etching treatment, and the micro-hole is etched on the surface of the aluminum member; the aluminum member formed by etching the micro-hole is electrically colored, and a white surface is formed on the surface of the aluminum member. The layer is subjected to dehydration treatment and drying treatment;

Wherein the electrochromic treated electrolyte is a white colored paste comprising water, paint and a white paste; and the mass ratio of the water, paint and white paste is (12-13): (2-3 ) : (1-1.2).

[Claim 2] The preparation method according to claim 1, wherein the paint comprises a component of the following mass parts:

Acetate hydroxyethyl ester 5±0.2 parts

Butyl acrylate 3±0.2 parts

Glycidylglycerol 2.5±0.1 parts

Lactic acid 1 soil O.lfo'

Propylene glycol phenyl ether 0.8 ± 0.1 parts.

[Claim 3] The preparation method according to claim 1, wherein the white paste comprises the following components:

White toner 3±0.3 parts, organic solvent 5±1 parts.

[Claim 4] The preparation method according to any one of claims 1 to 3, wherein the conditions of the electro-coloring treatment are: a direct current voltage of 125V-130V, and an electrolyte temperature control of 25-27 °C. The pH of the electrolyte is 7.0-7.5.

[Claim 5] The preparation method according to any one of claims 1 to 3, wherein the white film layer has a thickness of 5-8 μm.

[Claim 6] The preparation method according to any one of claims 1 to 3, wherein the dehydration treatment is to immerse the aluminum member subjected to the electro-coloring treatment in a dehydration liquid; wherein, the dehydration The liquid includes a surfactant and water, and the mass ratio of the surfactant to water is (1-2): 100; and/or The drying process includes a pre-baking process and a post-baking process, the pre-baking process has a temperature of 75-82 ° C, a daytime of 9-l lmin, and a post-baking process temperature of 178- 182 ° C, 38-41 min.

The production method according to claim 6, wherein the surfactant is at least one of anhydrous ethanol and glycerin.

The preparation method according to any one of claims 1 to 3, wherein the pore diameter of the micropores is 50 to 70 nm; and/or

The plurality of micropores are distributed in a honeycomb shape on the surface of the aluminum member.

The preparation method according to any one of claims 1 to 3, characterized in that, after performing the micro-etching treatment on the aluminum member, before performing the electro-coloring treatment, further comprising the aluminum member The surface treatment is performed by placing the aluminum member subjected to the micro-etching treatment in a MICRO CLEAN F4 solution for cleaning treatment.

The preparation method according to claim 9, wherein the MICRO CLEAN F4 solution comprises a MICRO CLEAN F4 cleaning agent and water, and the ratio of the MICRO CLEAN F4 cleaning agent to water is (1-1.5): (5) -6), and control the pH of the MICRO CLEAN F4 solution to 8.5-9.

According to claims 1-3,

The method of claim 7, wherein the performing the surface micro-etching treatment on the aluminum member comprises the following steps:

The aluminum member is sequentially subjected to degreasing treatment, alkali etching treatment and pretreatment of the neutralization treatment; and the surface of the aluminum member subjected to the pretreatment is subjected to anodic electrolysis to form micropores on the surface of the aluminum member;

The aluminum member subjected to the anodic electrolysis treatment is subjected to a reaming treatment.

The preparation method according to claim 11, wherein the conditions of the anodic electrolysis treatment are:

The anodic electrolytically treated electrolyte comprises a concentration of 280-300 g/L of sulfuric acid and 1.0-2 g/L of oxalic acid;

Temperature: 18-20 ° C, daytime: 18-20 min, voltage: 18-20V;

The concentration of aluminum ions in the electrolyte during the electrochemical anode treatment is controlled to be 4-7 g/L. The preparation method according to claim 12, wherein the voltage is raised to 20 V at a constant rate in 1 minute.

The preparation method according to any one of claims 11 to 13, wherein the pores formed by the anodic electrolytic treatment have a pore diameter of 30 to 35 nm; and/or

The pores formed by the reaming treatment have a pore diameter of 50 to 70 nm.

A white aluminum member, comprising an aluminum member body, wherein: the surface of the aluminum member body is etched with a plurality of micropores, and at least the micropores are electrically colored with a white film layer; wherein the white film layer is formed The white coloring paste includes water, paint, and white slurry; and the mass ratio of the water, paint, and white slurry is (12-13): (2-3): (1-1.2).

The preparation method according to claim 15, wherein the paint comprises components of the following mass parts:

Acetate hydroxyethyl ester 5±0.2 parts

Butyl acrylate 3±0.2 parts

Glycidylglycerol 2.5±0.1 parts

Lactic acid 1 ± 0.1 parts

Propylene glycol phenyl ether 0.8 ± 0.1 parts.

The preparation method according to claim 15, wherein the white paste comprises the following components in the following parts:

White toner 3±0.3 parts, organic solvent 5±1 parts.

The preparation method according to any one of claims 15-17, wherein the conditions of the electro-coloring treatment are: a direct current voltage of 125-130 V, an electrolyte temperature control of 25-27 ° C, and a pH of the electrolyte. It is 7.0-7.5.

The preparation method according to any one of claims 15-17, wherein the white film layer has a thickness of 5-8 μm.

The preparation method according to any one of claims 15-17, wherein the pores have a pore diameter of 50 to 70 nm.

The preparation method according to any one of claims 15-17, wherein the plurality of micropores are distributed in a honeycomb shape on a surface of the aluminum member. [Claim 22] The preparation method according to any one of claims 15-17, wherein the white aluminum member is any one of a mobile phone case, a computer case, an air conditioner frame and a casing, and a TV case. Species