Method for improving warping of electrolytic copper foil

Abstract

The invention relates to a method for improving warping of an electrolytic copper foil. According to the method, sodium 3, 3 '-dithiodipropane sulfonate is added into an electrolyte. The electrolytic copper foil prepared by the method has relatively low warpage, is more suitable for automatic production of CCL and PCB lamination, and effectively improves the production yield of downstream products.

Description

Technical Field

[0001] The invention belongs to the technical field of electrolytic copper foil, and in particular relates to a method for improving the warping of electrolytic copper foil. Background Art

[0002] Printed circuit boards (PCBs) are crucial components in the electronics industry, often called the "mother of electronic products." PCBs rely on copper foil circuits to transmit current and signals. Electrolytic copper foil, a primary raw material in PCB and CCL production, is known as a neural network. During the production process, electrolytic copper foil generates certain stresses. When these stresses exceed a certain value, the foil warps. This warping affects stacking and cutting processes for downstream customers (PCBs and CCLs), ultimately preventing them from achieving continuous automation, severely impacting their production efficiency and product dimensional stability.

[0003] Under current production conditions, the warping of electrolytic copper foil can only be improved by adding excessive collagen, but adding excessive collagen will also bring new problems, such as seersucker and vertical stripes. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for improving the warping of electrolytic copper foil. The electrolytic copper foil prepared by this method has lower warping and is more suitable for the automated production of CCL and PCB pressing, effectively improving the production yield of downstream products.

[0005] The present invention provides a method for improving the warping of electrolytic copper foil, comprising the following steps: Adding sodium polydisulfide dipropylene sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and ultimately produces electrolytic copper foil with low warpage.

[0006] Preferably, the addition amount of the sodium polydisulfide dipropane sulfonate is 0.5-5 mg / L.

[0007] Preferably, the components of the electrolyte include Cu 2+ 90-100g / L, H2SO4 120-130g / L, temperature 50-60℃, current density 8000-9000A / m 2 .

[0008] Preferably, the components of the electrolyte further include collagen with a concentration of 1-5 ppm and a molecular weight of 1000-2000 Daltons.

[0009] Preferably, the low warpage refers to cutting a copper foil of 100*100 mm in size, placing it on a glass table with the rough side facing up, measuring the height of the upward bending of the four corners, and taking the maximum value as the warpage value of the copper foil, which is ≤5 mm.

[0010] The invention improves the grain structure of the electrolytic copper foil by adding a certain amount of sodium polydisulfide dipropane sulfonate, thereby releasing the stress of the copper foil and balancing the compressive stresses of the rough and smooth surfaces of the electrolytic copper foil, thereby ultimately improving the warping of the electrolytic copper foil.

[0011] Beneficial effects The electrolytic copper foil prepared by the present invention has lower warpage and is more suitable for the automated production of CCL and PCB pressing, effectively improving the production yield of downstream products. DETAILED DESCRIPTION

[0012] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0013] Example 1 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 0.5mg / L.

[0014] Example 2 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 1.0mg / L.

[0015] Example 3 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 1.5mg / L.

[0016] Example 4 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 2.0mg / L.

[0017] Example 5 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 2.5mg / L.

[0018] Example 6 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, collagen concentration: 1.5ppm, sodium polydisulfide bispropane sulfonate: 3.0mg / L.

[0019] Example 7 Adding sodium polydisulfide dipropane sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and finally produces the electrolytic copper foil with low warpage; wherein, the electrolyte composition is Cu 2+ :93g / L, H2SO4:125g / / L, temperature:54℃, current density:8566A / m 2 , collagen molecular weight: 1500 Daltons, and collagen concentration: 1.5ppm.

[0020] Table 1 Relationship between warping and collagen of different concentrations and molecular weights From the results in the above table, we can see that under certain conditions, with the increase of sodium polydipropylene glycol disulfide sulfonate, the warpage of electrolytic copper foil tends to first decrease and then increase.

[0021] In summary, the preferred concentration is 1.5 mg / L sodium polydisulfide dipropane sulfonate.

Claims

1. A method for improving the warpage of electrolytic copper foil, comprising the following steps: Adding sodium polydisulfide dipropylene sulfonate to the electrolyte improves the grain structure of the electrolytic copper foil, and ultimately produces electrolytic copper foil with low warpage.

2. The method according to claim 1, wherein: The addition amount of the sodium polydisulfide dipropane sulfonate is 0.5-5 mg / L.

3. The method according to claim 1, wherein: The components of the electrolyte include Cu 2+ 90-100g / L, H2SO4 120-130g / L, temperature 50-60℃, current density 8000-9000A / m 2 .

4. The method according to claim 3, wherein: The components of the electrolyte also include collagen with a concentration of 1-5 ppm and a molecular weight of 1000-2000 Daltons.

5. The method according to claim 1, wherein: The low warpage refers to cutting a copper foil of 100*100mm in size, placing it on a glass table with the rough side facing up, measuring the height of the upward bending of the four corners, and taking the maximum value as the warpage value of the copper foil, which is ≤5mm.

Images