Alkaline electroplating indium composition and use method thereof

Abstract

The invention relates to an alkaline electroplating indium composition and a use method thereof, and belongs to the technical field of coating protection processes, and the alkaline electroplating indium composition comprises the following preparation raw materials in parts by weight: 6-8 parts of an indium composition, 3-5 parts of a complexing agent and 1-3 parts of caustic alkali. The alkaline electroplating indium composition prepared from the indium composition composed of sulfuric acid and methanesulfonic acid, the complexing agent composed of citric acid and the caustic alkali composed of potassium hydroxide is more uniform after forming a film on the metal surface, and in addition, an electroplating film on the surface of a nickel metal sheet has good wettability, so that the surface tension is better; furthermore, a uniform coating or printing effect can be formed outside the electroplating film more easily, and good surface adhesion of the electroplating film and good binding force of a passive film can be ensured; the scratch-resistant agent prepared from the tin powder, the copper powder and the titanium powder can effectively improve the scratch resistance of the surface of an electroplated layer formed by the alkaline electroplating indium composition.

Description

Technical Field

[0001] The invention belongs to the technical field of coating protection technology, and in particular relates to an alkaline indium electroplating composition and a use method thereof. Background Art

[0002] The traditional coating protection process is to form an organic protective film on the copper surface through chemical solutions, thereby forming an anti-oxidation, heat-resistant and moisture-resistant protection for the bottom coating. However, the surface and interior of the metal surface film prepared by the traditional coating protection process are uneven, the adhesion is low, and the passivation film has poor bonding strength, which makes the passivation film not resistant to high temperature and organic cleaning, reduces corrosion resistance, affects the appearance, and causes the passivation film to fall off. Summary of the invention

[0003] The object of the present invention is to provide an alkaline indium electroplating composition and a method for using the same in order to solve the above problems.

[0004] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0005] The present invention provides an alkaline electroplating indium composition, wherein the raw materials for preparing the composition include, by weight: 6-8 parts of indium composition, 3-5 parts of complexing agent, and 1-3 parts of caustic alkali;

[0006] Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources;

[0007] The water-soluble indium ion source includes sulfuric acid, nitric acid, methanesulfonic acid, methylsulfonic acid, ethanesulfonic acid, butanesulfonic acid and carboxylic acid;

[0008] Wherein, the complexing agent comprises, by weight, one or more organic acids soluble in an aqueous environment;

[0009] The organic acid soluble in an aqueous environment includes nicotinic acid, citric acid, gluconic acid, malic acid, tartaric acid, a compound containing a phosphate group, quinoline and hydroxyquinoline, and the total concentration of the complexing agent is 20-200 g / L;

[0010] Wherein, the caustic alkali is at least one selected from the following by weight: sodium hydroxide and potassium hydroxide, and the total concentration thereof is 20-200 g / L.

[0011] As a further optimization scheme of the present invention, the carboxylic acid is specifically citric acid, acetic acid or glyoxylic acid.

[0012] As a further optimization scheme of the present invention, the compound containing a phosphate group is specifically amino trimethylene phosphonic acid, hydroxy ethylidene diphosphonic acid, ethylenediamine tetramethylene phosphonic acid or diethylenetriamine penta methylene phosphonic acid.

[0013] As a further optimization scheme of the present invention, the pH value of the caustic soda is 12.

[0014] As a further optimization scheme of the present invention, the raw materials for preparing the alkaline electroplating indium composition further include, by weight: 3-6 parts of a scratch resistant agent;

[0015] Wherein, by weight, the raw materials for preparing the scratch-resistant agent include 3-5 parts of tin powder, 6-8 parts of copper powder, and 1-2 parts of titanium powder.

[0016] As a further optimization scheme of the present invention, the preparation method of the scratch-resistant agent is: tin powder, copper powder and titanium powder are uniformly mixed and stirred, and the stirring speed is controlled to be 10-16 r / min and the control time is controlled to be 20-30 min.

[0017] As a further optimization scheme of the present invention, the preparation method of the alkaline electroplating indium composition is: uniformly mixing and stirring the indium composition, the complexing agent, the caustic alkali and the scratch resistant agent, controlling the stirring speed to 10-16r / min, and controlling the time to 20-30min

[0018] A method for using the alkaline indium electroplating composition is characterized by comprising the following steps:

[0019] The alkaline indium electroplating composition is poured into the electroplating tank, and the alkaline indium electroplating composition is energized at a temperature of 15-35° C., the energization time is 1-300 seconds, and the current density is 1-10 ASD to perform electroplating.

[0020] The beneficial effects of the present invention are as follows: the alkaline electroplated indium composition composed of sulfuric acid and methanesulfonic acid, the complexing agent composed of citric acid and the caustic soda composed of potassium hydroxide are prepared, and the alkaline electroplated indium composition is more uniform after film formation on the metal surface. In addition, the electroplated film on the surface of the nickel metal sheet has good wettability, so that the surface tension is better, and it is easier to form a uniform coating or printing effect on the outside of the electroplated film, which helps to ensure good adhesion of the electroplated film surface and good bonding force of the passivation film; the scratch-resistant agent made of tin powder, copper powder and titanium powder can effectively improve the ability of the electroplated layer formed by the alkaline electroplated indium composition to resist scratches on the surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the appearance of the present invention;

[0022] Figure 2 It is a microscopic schematic diagram of the present invention;

[0023] Figure 3 This is a schematic diagram of the performance of Example 2 of the present invention when applied with a dyne pen;

[0024] Figure 4This is a schematic diagram of the performance of comparative example 3 of the present invention when applied with a dyne pen. DETAILED DESCRIPTION

[0025] The present application is described in further detail below. It is necessary to point out that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technicians in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0026] 1. Materials

[0027] Unless otherwise specified, the methods used in the present invention are conventional methods known to those skilled in the art, and the reagents and other materials used are commercially available products unless otherwise specified.

[0028] (1) In the present invention;

[0029] The water in the present invention is pure water.

[0030] 2. Embodiment

[0031] Example 1

[0032] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 6 parts of indium composition, 3 parts of complexing agent, and 1 part of caustic alkali (the pH value of the caustic alkali is 12);

[0033] Wherein, the indium composition includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5) by weight, and the total concentration of the indium composition is 25 g / L;

[0034] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0035] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0036] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 3 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 3 parts of tin powder, 6 parts of copper powder, and 1 part of titanium powder;

[0037] Scratch resistant agent: Evenly mix tin powder, copper powder and titanium powder, control the stirring speed to 10r / min, and control the time to 20min;

[0038] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and anti-scratch agent are uniformly mixed and stirred, and the stirring speed is controlled to be 10r / min and the control time is 20min;

[0039] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 15° C., applying power for 1 second, and carrying out electroplating at a current density of 1ASD.

[0040] Example 2

[0041] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0042] Wherein, the indium composition includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5) by weight, and the total concentration of the indium composition is 25 g / L;

[0043] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0044] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0045] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 4 parts of tin powder, 7 parts of copper powder, and 1.5 parts of titanium powder;

[0046] Scratch resistant agent: Evenly mix tin powder, copper powder and titanium powder, control the stirring speed to 13r / min, and control the time to 25min;

[0047] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 13r / min and the control time is 25min;

[0048] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0049] Example 3

[0050] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 8 parts of indium composition, 5 parts of complexing agent, and 3 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0051] Wherein, the indium composition includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5) by weight, and the total concentration of the indium composition is 25 g / L;

[0052] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0053] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight.

[0054] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 6 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 5 parts of tin powder, 8 parts of copper powder, and 2 parts of titanium powder;

[0055] Scratch resistant agent: Evenly mix tin powder, copper powder and titanium powder, control the stirring speed to 16r / min, and control the time to 30min;

[0056] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 16r / min and the control time is 30min;

[0057] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating bath, applying power to the alkaline electroplating indium composition at a temperature of 35° C. for 300 seconds at a current density of 10 ASD, and performing electroplating.

[0058] Comparative Example 1

[0059] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0060] Wherein, the indium composition is nitric acid, and the total concentration of the indium composition is 5 g / L, by weight;

[0061] Wherein, by weight, the complexing agent is aminotri(methylenephosphonic acid), and the total concentration of the complexing agent is 40 g / L;

[0062] Wherein, the caustic alkali is sodium hydroxide, and its total concentration is 90g / L by weight;

[0063] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 4 parts of tin powder, 7 parts of copper powder, and 1.5 parts of titanium powder;

[0064] Scratch resistant agent: Evenly mix tin powder, copper powder and titanium powder, control the stirring speed to 13r / min, and control the time to 25min;

[0065] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 13r / min and the control time is 25min;

[0066] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0067] Comparative Example 2

[0068] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition;

[0069] Wherein, the indium composition is sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5) by weight, and the total concentration of the indium composition is 25 g / L;

[0070] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 4 parts of tin powder, 7 parts of copper powder, and 1.5 parts of titanium powder;

[0071] Scratch resistant agent: Evenly mix tin powder, copper powder and titanium powder, control the stirring speed to 13r / min, and control the time to 25min;

[0072] Alkaline electroplating indium composition: the indium composition and the scratch resistant agent are uniformly mixed and stirred, the stirring speed is controlled to be 13r / min, and the control time is 25min;

[0073] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0074] Comparative Example 3

[0075] Prepare a sealing agent (SF1003 Guangzhou Tianzhi Environmental Protection Technology Co., Ltd.) working solution, use copper material nickel-plated and silver-plated, and soak for 10 seconds.

[0076] Comparative Example 4

[0077] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0078] Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources;

[0079] The water-soluble indium ion source includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5), and the total concentration of the indium composition is 25 g / L;

[0080] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0081] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0082] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 3 parts of copper powder and 2.5 parts of titanium powder;

[0083] Scratch resistant agent: Mix copper powder and titanium powder evenly, control the stirring speed to 13r / min, and control the time to 25min;

[0084] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 13r / min and the control time is 25min;

[0085] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0086] Comparative Example 5

[0087] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0088] Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources;

[0089] The water-soluble indium ion source includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5), and the total concentration of the indium composition is 25 g / L;

[0090] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0091] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0092] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 9 parts of tin powder and 3.5 parts of titanium powder;

[0093] Scratch resistant agent: Mix tin powder and titanium powder evenly, control the stirring speed to 13r / min, and control the time to 25min;

[0094] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 13r / min and the control time is 25min;

[0095] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0096] Comparative Example 6

[0097] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0098] Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources;

[0099] The water-soluble indium ion source includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5), and the total concentration of the indium composition is 25 g / L;

[0100] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0101] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0102] The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 5 parts of a scratch resistant agent, wherein, by weight, the raw materials for preparing the scratch resistant agent include 4.5 parts of tin powder and 8 parts of copper powder;

[0103] Scratch resistant agent: Mix tin powder and copper powder evenly, control the stirring speed to 13r / min, and control the time to 25min;

[0104] Alkaline electroplating indium composition: the indium composition, complexing agent, caustic alkali and scratch resistant agent are uniformly mixed and stirred, and the stirring speed is controlled to be 13r / min and the control time is 25min;

[0105] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0106] Comparative Example 7

[0107] An alkaline electroplating indium composition, wherein the raw materials for its preparation include, by weight: 7 parts of indium composition, 4 parts of complexing agent, and 2 parts of caustic alkali (the pH value of the caustic alkali is 12);

[0108] Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources;

[0109] The water-soluble indium ion source includes sulfuric acid and methanesulfonic acid (the mass ratio of sulfuric acid to methanesulfonic acid is 1:1.5), and the total concentration of the indium composition is 25 g / L;

[0110] Wherein, the complexing agent is citric acid, and the total concentration of the complexing agent is 130 g / L by weight;

[0111] Wherein, the caustic alkali is potassium hydroxide, and its total concentration is 150g / L by weight;

[0112] Alkaline electroplating indium composition: uniformly mix and stir the indium composition, complexing agent and caustic alkali, control the stirring speed to 13r / min, and control the time to 25min;

[0113] A method for using the above-mentioned alkaline electroplating indium composition comprises the following steps: pouring the alkaline electroplating indium composition into an electroplating tank, applying power when the alkaline electroplating indium composition is at a temperature of 25° C., applying power for 10 seconds, and carrying out electroplating at a current density of 2ASD.

[0114] 3. Test experiment (refer to the attached figure of the instruction manual) Figure 1-4 )

[0115] 3.1 Appearance and micro-observation experiments

[0116] (1) Experimental procedures

[0117] The alkaline indium electroplating composition prepared by Examples 1-3 and Comparative Examples 1-2 was electroplated on a nickel metal sheet, and then the nickel metal sheet was photographed and observed and scanned by SEM at a magnification of 2.5K. Figure 1 and Figure 2 As shown:

[0118] Depend on Figure 1It can be seen from the comparison of the appearance pictures in that compared with Example 1, Example 3 and Comparative Examples 1-2, Example 2 has a uniform and smooth overall appearance, and Example 2 is the best;

[0119] Depend on Figure 2 It can be seen from the comparison of the microscopic pictures in that compared with Example 1, Example 3 and Comparative Examples 1-2, Example 2 is microscopically uniform and flat as a whole, and Example 2 is the best;

[0120] In summary, the alkaline electroplating indium composition prepared by the indium composition composed of sulfuric acid and methanesulfonic acid, the complexing agent composed of citric acid and the caustic soda composed of potassium hydroxide is more uniform after film formation on the metal surface.

[0121] 3.2 Dyne pen test experiment

[0122] (1) Experimental procedures

[0123] The alkaline indium electroplating composition prepared in Example 2 and Comparative Example 3 was electroplated on a nickel metal sheet, and then a mark was drawn on the nickel metal sheet using a 36# dyne pen, and then the nickel metal sheet was photographed and observed. Figure 3 and Figure 4 As shown:

[0124] Depend on Figure 3 and Figure 4 From the comparison of the pictures in , it can be seen that, compared with Example 3, the dyne pen in Example 2 is easier to remain on the surface of the electroplated film, thereby knowing that the electroplated film on the surface of the nickel metal sheet has good wettability, and it is easier to form a uniform coating or printing effect on the outside of the electroplated film.

[0125] 3.3 Scratch resistance test

[0126] (1) Experimental procedures

[0127] ① Take 10 portions of each of the alkaline indium electroplating compositions prepared in Example 2 and Comparative Examples 4-7;

[0128] ② electroplating 50 parts of the alkaline indium electroplating composition on the nickel metal sheets;

[0129] ③ Use a scratch resistance tester to test the scratch resistance of the electroplated layer formed on the surface of the nickel metal sheet;

[0130] ④ The depth and length of the scratches produced on the surface of the electroplated layer formed by the alkaline electroplating indium composition prepared in the same embodiment or comparative example are averaged, as shown in the following table:

[0131] project depth length Example 2 0.001nm 0.3mm Comparative Example 4 0.01nm 2.1mm Comparative Example 5 0.2nm 3mm Comparative Example 6 0.1nm 5mm Comparative Example 7 0.2nm 6mm

[0132] From the comparison of the pictures in the above table, it can be seen that compared with comparative examples 4-7, the scratch-resistant agent made of tin powder, copper powder and titanium powder in Example 2 can effectively improve the scratch resistance of the surface of the electroplated layer formed by the alkaline electroplated indium composition.

[0133] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An alkaline indium electroplating composition, characterized in that The raw materials for its preparation include, by weight: 6-8 parts of indium composition, 3-5 parts of complexing agent, and 1-3 parts of caustic alkali; Wherein, the indium composition comprises, by weight, one or more water-soluble indium ion sources; The water-soluble indium ion source includes sulfuric acid, nitric acid, methanesulfonic acid, methylsulfonic acid, ethanesulfonic acid, butanesulfonic acid and carboxylic acid; Wherein, the complexing agent comprises, by weight, one or more organic acids soluble in an aqueous environment; The organic acid soluble in an aqueous environment includes nicotinic acid, citric acid, gluconic acid, malic acid, tartaric acid, a compound containing a phosphate group, quinoline and hydroxyquinoline, and the total concentration of the complexing agent is 20-200 g / L; Wherein, the caustic alkali is at least one selected from the following by weight: sodium hydroxide and potassium hydroxide, and the total concentration thereof is 20-200 g / L.

2. An alkaline indium electroplating composition according to claim 1, characterized in that: The carboxylic acid is specifically citric acid, acetic acid or glyoxylic acid.

3. An alkaline indium electroplating composition according to claim 1, characterized in that: The compound containing a phosphoric acid group is specifically amino trimethylene phosphonic acid, hydroxy ethylidene diphosphonic acid, ethylenediamine tetramethylene phosphonic acid or diethylenetriamine pentamethylene phosphonic acid.

4. An alkaline indium electroplating composition according to claim 1, characterized in that: The pH value of the caustic soda is 12.

5. An alkaline indium electroplating composition according to claim 1, characterized in that: The raw materials for preparing the alkaline electroplating indium composition further include, by weight: 3-6 parts of a scratch resistant agent; Wherein, by weight, the raw materials for preparing the scratch-resistant agent include 3-5 parts of tin powder, 6-8 parts of copper powder, and 1-2 parts of titanium powder.

6. An alkaline indium electroplating composition according to claim 5, characterized in that: The preparation method of the scratch-resistant agent is: uniformly mixing tin powder, copper powder and titanium powder, and stirring the mixture, controlling the stirring speed to 10-16 r / min, and controlling the time to 20-30 min.

7. An alkaline indium electroplating composition according to claim 1, characterized in that: The preparation method of the alkaline electroplating indium composition is: uniformly mixing and stirring the indium composition, the complexing agent, the caustic alkali and the anti-scratch agent, controlling the stirring speed to 10-16 r / min, and controlling the time to 20-30 min.

8. A method for using the alkaline indium electroplating composition according to any one of claims 1 to 7, characterized in that: The following steps are involved: The alkaline indium electroplating composition is poured into the electroplating tank, and the alkaline indium electroplating composition is energized at a temperature of 15-35° C., the energization time is 1-300 seconds, and the current density is 1-10 ASD to perform electroplating.

Images