Etching solution for refining metal grid nodes

Abstract

The invention discloses an etching solution for refining metal grid nodes, which comprises the following components in percentage by mass: 40-50% of a main etching agent, 20-30% of an etching auxiliary agent, 10-20% of a wetting agent and 5-10% of a bank protection agent, the main etching agent comprises a chemical agent with relatively good etching capability on metal copper, the main etching agent comprises one of inorganic acid, ammonium persulfate and ferric trichloride, the pH value of etching liquid in the main etching agent is 2-6, the etching auxiliary agent adopts an oxidizing etching auxiliary agent, the etching auxiliary agent adopts one of sodium chlorate or hydrogen peroxide, and the etching auxiliary agent adopts one of sodium chloride or hydrogen peroxide. According to the invention, through selection and content allocation of the main etching agent and the auxiliary etching agent in the metal grid node refinement etching liquid, and through addition of the wetting agent and the bank protection agent, refined etching and node refinement of the metal grid are realized, and the defects of uneven line width, serious lateral erosion, thick and large nodes and the like in the process of preparing the metal grid by using the existing etching liquid are overcome; and the node refining etching liquid provided by the invention can greatly improve the appearance and the light transmittance performance of the metal grid product.

Description

Technical Field

[0001] The invention relates to the technical field of chemical etching agents, in particular to an etching solution for refining metal grid nodes. Background Art

[0002] As a key capacitive touch screen component, metal grid is widely used in touch screen panels due to its excellent conductivity, high transmittance and good flexibility. The copper film yellow photoetching process is one of the most mature technologies for preparing metal grids. It involves using photoresist as a mask to define the metal grid pattern through exposure and development steps, and then removing the copper film area not protected by the photoresist through an etching process to form a fine metal grid structure.

[0003] However, there are some defects in the existing yellow light subtractive process. In particular, during the copper film etching process, copper ions tend to gather in large quantities at the grid nodes, which will lead to obstructed mass transfer, slow down the exchange rate of the etching solution, and then cause the nodes to become thicker. This node coarsening phenomenon not only reduces the transmittance of the metal grid, but also affects its appearance quality, ultimately affecting the performance and user experience of the entire touch screen. Summary of the invention

[0004] The object of the present invention is to provide an etching solution for metal grid node refinement to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solution: an etching solution for metal grid node refinement, the etching solution is composed of the following according to mass percentage: 40%-50% main etching agent, 20%-30% etching auxiliary agent, 10%-20% wetting agent, and 5%-10% revetment agent.

[0006] Preferably, the main etchant includes a chemical agent having good etching ability for metallic copper, and the main etchant includes one of inorganic acid, ammonium persulfate, and ferric chloride.

[0007] Preferably, the addition of the main etchant makes the pH of the etching solution 2-6.

[0008] Preferably, the etching auxiliary agent is an oxidizing etching auxiliary agent.

[0009] Preferably, the etching auxiliary agent is selected from sodium chlorate or hydrogen peroxide.

[0010] Preferably, the total content of the etching auxiliary agent is 0.1-3 mol / L.

[0011] Preferably, the wetting agent is one of sulfate or sulfonate series.

[0012] Preferably, the wetting agent content is 0.01-50 g / L.

[0013] Preferably, the shore protection agent is one of fatty mercaptan or thioether.

[0014] Preferably, the content of the bank protection agent is controlled at 0.01-10 g / L.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention achieves fine etching and node refinement of the metal mesh by selecting and adjusting the content of the main and auxiliary etchants in the metal mesh node refinement etching solution, and adding a wetting agent and a shore protection agent, thereby solving the defects of uneven line width, severe side etching, and coarse nodes in the process of preparing metal meshes with existing etching solutions. The node refinement etching solution provided by the present invention significantly improves the appearance and transmittance performance of the metal mesh product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a comparison chart of the etching effects of the common etching solution and the node refinement etching solution of the present invention.

[0018] A is the effect of ordinary etching solution, and B is the effect of node refinement etching solution. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 The present invention provides a technical solution: an etching solution for metal grid node refinement, wherein the etching solution is composed of the following components according to mass percentage: 40%-50% of a main etching agent, 20%-30% of an etching auxiliary agent, 10%-20% of a wetting agent, and 5%-10% of a shore protection agent.

[0021] The main etchant includes a chemical agent with good etching ability for metallic copper, and the main etchant includes one of an inorganic acid, ammonium persulfate, and ferric chloride; in the etching of the copper film, in view of the accumulation effect of copper ions at the nodes, in order to avoid using chemical reagents containing copper ions, sulfuric acid can be used as the main etchant, and the addition of the main etchant makes the pH of the etching solution 2-6.

[0022] The main etchant is mainly responsible for the dissolution of the metal, the inorganic acid provides strong etching ability, and the organic acid provides a milder etching to control the process.

[0023] The etching auxiliary agent uses an oxidizing etching auxiliary agent. The etching auxiliary agent is a chemical additive used to enhance the etching ability of the etching main agent. For the inorganic acid system, it can greatly enhance the etching ability and broad spectrum of the etching solution. The etching auxiliary agent is selected from sodium chlorate or hydrogen peroxide, and the total content of the etching auxiliary agent is 0.1-3 mol / L.

[0024] Etching aids promote the uniformity of the etching process and improve etching efficiency. Chlorides increase the ionic strength and inorganic peroxides act as oxidants to help remove oxides from the metal surface.

[0025] The wetting agent reduces the surface tension of the etching solution by adding the wetting agent, thereby significantly changing the mass transfer characteristics of the etching solution. The wetting agent mainly includes ionic wetting agents and non-ionic wetting agents. The wetting agent adopts one of the sulfate or sulfonate series, and the wetting agent content is 0.01-50g / L.

[0026] The wetting agent ensures good wettability of the etching solution on the metal surface and ensures that the etching solution evenly covers the metal surface.

[0027] Bank protection agent, also known as selective protective agent, can reduce the test and protect the line side during the etching process, which is beneficial to improve the regularity and stability of the line. The bank protection agent uses one of the fatty mercaptan or sulfide, and the content of the bank protection agent is controlled at 0.01-10g / L.

[0028] Shore protection agents effectively protect metal surfaces from excessive corrosion, weak acid and weak base salts maintain pH stability, and amines act as buffers.

[0029] Embodiment 1:

[0030] The process of etching solution preparation includes the following steps:

[0031] S1: Preparation of main etchant: hydrochloric acid and acetic acid are selected as the main etchants and mixed at a mass percentage of 45%. Inorganic acid provides strong etching ability, while organic acid provides milder etching control. The combination of the two can achieve efficient metal dissolution;

[0032] S2: Sodium chloride and hydrogen peroxide are added to the main etchant, accounting for 25% of the total mass. Chloride increases the ionic strength of the solution and promotes the uniformity of the reaction. Inorganic peroxide acts as an oxidant to help remove oxides on the metal surface and improve etching efficiency.

[0033] S3: adding isopropyl alcohol as a wetting agent to the mixture in the above step, the proportion of which is 15%. The wetting agent ensures good coverage of the etching solution on the metal surface to avoid uneven etching or spots caused by insufficient wetting;

[0034] S4: Sodium bicarbonate and triethylamine are added as shore protection agents at a ratio of 7%. The shore protection agent can effectively maintain the pH value of the solution, prevent excessive corrosion of the metal surface, and provide additional protection for the metal surface;

[0035] S5: After all components are mixed, use a stirrer to stir thoroughly to ensure uniform mixing, check the pH value of the final mixture, and the etching solution pH is 4.2.

[0036] Embodiment 2:

[0037] The process of etching solution preparation includes the following steps:

[0038] S1: Preparation of main etchant: hydrochloric acid and acetic acid are selected as main etchants and mixed according to a mass percentage of 30%;

[0039] S2: adding sodium chloride and hydrogen peroxide to the main etchant, with the total weight accounting for 25%;

[0040] S3: adding isopropyl alcohol as a wetting agent to the mixture in the above step, the proportion of which is 15%;

[0041] S4: sodium bicarbonate and triethylamine are added as shore protection agents, the proportion of which is 7%;

[0042] S5: After all components are mixed, use a stirrer to stir thoroughly to ensure uniform mixing, check the pH value of the final mixture, and the etching solution pH is 1.5.

[0043] Embodiment three:

[0044] The process of etching solution preparation includes the following steps:

[0045] S1: Preparation of main etchant: hydrochloric acid and acetic acid are selected as main etchants and mixed according to a mass percentage of 60%;

[0046] S2: adding sodium chloride and hydrogen peroxide to the main etchant, with the total weight accounting for 25%;

[0047] S3: adding isopropyl alcohol as a wetting agent to the mixture in the above step, the proportion of which is 15%;

[0048] S4: sodium bicarbonate and triethylamine are added as shore protection agents, the proportion of which is 7%;

[0049] S5: After all components are mixed, use a stirrer to stir thoroughly to ensure uniform mixing, check the pH value of the final mixture, and the etching solution pH is 7.2.

[0050] In summary, in the above three groups of embodiments, the contents of the components of the etching solution in Embodiment 1 meet the expected etching requirements.

[0051] The method of using the etching solution in the production of metal grid patterns includes the following steps:

[0052] S11: Cleaning the metal grid to be etched to remove surface oil and impurities;

[0053] S12: Immerse the cleaned metal grid in the prepared etching solution, and adjust the immersion time according to the etching depth and fineness requirements, the time is 5-15 minutes;

[0054] S13: After the etching process is completed, the metal grid is thoroughly washed with deionized water to remove the residual etching solution, and then dried, which can be done by air drying or baking.

[0055] In summary, the present invention achieves fine etching and node refinement of the metal mesh by selecting and adjusting the content of the main and auxiliary etchants in the metal mesh node refinement etching solution, and adding a wetting agent and a shore protection agent, thereby solving the defects of uneven line width, severe side etching, and coarse nodes in the process of preparing metal meshes with existing etching solutions. The node refinement etching solution provided by the present invention significantly improves the appearance and transmittance performance of the metal mesh product.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An etching solution for metal grid node refinement, Features: The etching solution is composed of the following components according to mass percentage: 40%-50% of a main etching agent, 20%-30% of an etching auxiliary agent, 10%-20% of a wetting agent, and 5%-10% of a shore protection agent.

2. The etching solution for metal grid node refinement according to claim 1, Features: The main etching agent includes a chemical agent with good etching ability for metal copper, and the main etching agent includes one of inorganic acid, ammonium persulfate and ferric chloride.

3. The etching solution for metal grid node refinement according to claim 1, Features: The addition of the main etchant makes the pH of the etching solution 2-6.

4. The etching solution for metal grid node refinement according to claim 1, Features: The etching auxiliary agent is an oxidizing etching auxiliary agent.

5. The etching solution for metal grid node refinement according to claim 4, Features: The etching auxiliary agent is selected from sodium chlorate or hydrogen peroxide.

6. The etching solution for metal grid node refinement according to claim 4, Features: The total content of the etching auxiliary agent is 0.1-3 mol / L.

7. The etching solution for metal grid node refinement according to claim 1, Features: The wetting agent is one of sulfate or sulfonate series.

8. The etching solution for metal grid node refinement according to claim 7, Features: The wetting agent content is 0.01-50g / L.

9. The etching solution for metal grid node refinement according to claim 1, Features: The bank protection agent is one of aliphatic mercaptan or thioether.

10. The etching solution for metal grid node refinement according to claim 9, Features: The content of the bank protection agent is controlled at 0.01-10 g / L.

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