EP4148165B1

EP4148165B1 - Method for preparing heat dissipation component with high flexibility made of graphite or graphene material

Info

Publication number: EP4148165B1
Application number: EP21199008.0A
Authority: EP
Inventors: Meixing Pang
Original assignee: Shenzhen Ruixi New Material Technology Co Ltd
Current assignee: Shenzhen Ruixi New Material Technology Co Ltd
Priority date: 2021-09-08
Filing date: 2021-09-24
Publication date: 2024-04-17
Anticipated expiration: 2041-09-24
Also published as: JP7187069B1; KR102631465B1; EP4148165C0; EP4148165A1; TWI777783B; CN113622007A; TW202311157A; KR20230036941A; US20230070481A1; JP2023039376A

Description

TECHNICAL FIELD

The present disclosure belong to the field of preparation of parts made of a graphite or graphene material, and relates to a method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material.

BACKGROUND

Graphite is a two-dimensional carbon nanomaterial presented with hexagonal honeycomb lattices and composed of carbon atoms in sp2 hybrid orbitals. Graphite has a very good thermal conduction performance. The pure and defect-free single-layer graphite has thermal conductivity up to 5300 W/mK, and is the carbon material with the highest thermal conductivity so far, and its thermal conductivity is higher than those of a single-walled carbon nanotube (3500 W/mK) and a multi-walled carbon nanotube (3000 W/mK). When it is used as a carrier, the thermal conductivity can also reach 600 W/MK. Furthermore, the ballistic thermal conductivity of graphite can lower the lower limit of the ballistic thermal conductivity of a carbon nanotube of unit circumference and length.
All kinds of electronic elements in electronic products need to dissipate heat. When traditional graphite or graphene is applied for heat dissipation of the electronic elements, it mainly fixes a metal layer on the surface of graphite or graphene, and in particular the metal layer is fixed onto graphite or graphene by bonding or electroplating, wherein electroplating is better than bonding in heat conduction efficiency.
In order to ensure the electroplating quality of the metal layer on the surface of graphite or graphene, it is usually necessary to subject the surface of graphite or graphene to multiple passes of cleaning processes before electroplating. During the cleaning process, after the surface of graphite or graphene is treated with an OP-10 surfactant, the smoothness of the surface of graphite or graphene is general, which leads to poor binding effect and uneven thickness of the metal layer electroplated on the surface of graphite or graphene, and thus affects the flexibility of the prepared heat dissipation component, and the surface of the heat dissipation component is easy to generate creases.
CN109748267 discloses a multi-pass cleaning based preparation method of a graphene heat-dissipating component. The preparation method comprises the following processing steps: 1), cleaning a grapheneraw material by using ultrasonic; 2), continuing cleaning the graphene raw material by using an activator, wherein the activator comprises 10-20% of sulfuric acid, 0.05-1% of a surfactant and the balance of water; 3), continuing cleaning the graphene raw material by using deionized water; 4), electroplating the graphene raw material to form a copper layer on the surface of graphene raw material;5), continuing cleaning the copper layer-electroplated graphene raw material by using deionized water; 6), continuing to dry the copper layer-electroplated graphene raw material.
CN108823615 discloses a preparation method of a high-heat-conductivity nanometer copper-graphite film composite material. The preparation method comprises the specific steps of: (1) chemical roughening of graphite films; (2) plasma treatment of the roughened graphite films; (3) copper electroplating of the plasma-treated graphite films; and (4) passivation of the graphite film after copper electroplating; and the high-heat-conductivity nanometer copper-graphite film composite material product is obtained through cleaning and drying after passivation.
CN103943281 describes a preparation method of an electric wire and cable with a copper-graphene complex phase conductive wire core. The preparation method includes the steps: preparing copper sulfate, sulfuric acid, surface active agents and hydrochloric acid into copper plating liquid; adding graphene nano-sheets into the copper plating liquid to obtain electroplating liquid containing graphene; taking a phosphor copper sheet as an anode, taking a washed substrate as a cathode, placing the phosphor copper sheet and the substrate into the electroplating liquid for electroplating to obtain a plate with a copper-graphene complex phase plating layer, and rolling and drawing the plate to form the conductive wire core. The conductive wire core is prepared by the aid of a copper-graphene complex phase, so that the obtained electric wire and cable is light in weight, high in mechanical strength, fine in conductivity and excellent in oxidation resistance and corrosion resistance. The preparation process is simple, the performances of the conductive wire core can be controlled by adjusting an electroplating process, and controllability of the process is high.

SUMMARY

An objective of the present disclosure is to provide a method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material, which includes the following steps: firstly, plasma cleaning a surface of graphite or graphene, and then treating the surface of graphite or graphene with an activator compounded by sulfuric acid, an OP-10 surfactant and sodium dodecyl sulfate, so that the surface of the material has good smoothness, and it ensures a copper film layer electroplated on the surface of graphite or graphene has good binding quality and uniform, and enhances the flexibility of the prepared heat dissipation component, and the surface of the heat dissipation component is not easy to generate creases.
In order to achieve the aforementioned objective, the present disclosure adopts the following technical solution: a method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material, including the following steps:

1) plasma cleaning a graphite or graphene raw material;
2) taking preparation materials of an activator including the following components in percentage by weight: 10-20% of sulfuric acid, 0.05-1% of an OP-10 surfactant, 0.05-1% of sodium dodecyl sulfate, and the balance being water;
3) mixing the aforementioned components of the activator to prepare the activator, and continually cleaning the graphite or graphene raw material with the activator;
4) continually cleaning the graphite or graphene raw material with deionized water;
5) conducting a electroplating process on a surface of the graphite or graphene raw material to form a copper film layer;
6) continually cleaning the graphite or graphene raw material electroplated with the copper film layer on the surface thereof with deionized water;
7) forming a protective film on the graphite or graphene raw material by soaking, including: the graphite or graphene raw material is firstly soaked in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film, and then put into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film; and
8) drying the graphite or graphene raw material electroplated with the copper film layer.

As a further description of the aforementioned technical solution:
In the step 1), the graphite or graphene raw material is placed in a plasma cleaning machine for cleaning.
As a further description of the aforementioned technical solution:
In the step 2), the activator includes the following components in percentage by weight: 12-16% of sulfuric acid, 0.05-0.5% of an OP-10 surfactant, 0.05-0.5% of sodium dodecyl sulfate, and the balance being water.
As a further description of the aforementioned technical solution:
in the step 2), the activator includes the following components in percentage by weight: 15% sulfuric acid, 0.1% of the OP-10 surfactant, 0.1% of sodium dodecyl sulfate, and the balance being water.
As a further description of the aforementioned technical solution:
in the step 5), the graphite or graphene raw material is subjected to the electroplating process twice with an electroplating solution, and the electroplating solution includes the following components in percentage by weight: 5% of copper ions; 14% of sulfuric acid; 0.8% of a brightener; 0.06% of an adjuvant; 0.06% of a leveling agent; and the balance being water.
As a further description of the aforementioned technical solution:
when the graphite or graphene raw material is electroplated with the electroplating solution for the first time, the temperature is 40 celsius degrees and the time is 20 minutes; and when the graphite or graphene raw material is electroplated with the electroplating solution for the second time, the temperature is 40 celsius degrees and the time is 15 minutes.
In view of the above, by employing the aforementioned technical solution, the present disclosure has the following beneficial effects.

1. in the present disclosure, the graphite or graphene raw material is firstly placed in a plasma cleaning machine for plasma cleaning, and then the surface of graphite or graphene is treated with an activator compounded by sulfuric acid, the OP-10 surfactant and sodium dodecyl sulfate. Sulphuric acid can wash away oil stains from the graphite or graphene raw material, the OP-10 surfactant improves the smoothness of the surface of the graphite or graphene raw material, and sodium dodecyl sulfate increases the dispersibility of graphite or graphene and further increases the smoothness of the surface of the graphite or graphene raw material, so that the electroplated copper film layer has good binding quality and is uniform, which enhances the flexibility of the prepared heat dissipation component, and the surface of the heat dissipation component is not easy to generate creases, and the heat dissipation and acid and alkali resistance performances of the heat dissipation component are improved.
2. In the present disclosure, after the copper film layer is formed on the graphite or graphene raw material by electroplating, the graphite or graphene raw material electroplated with the copper film layer is first soaked in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film on the copper film layer, and then put into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film on the copper film layer, which effectively prevents the copper film layer from color changing.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary examples of the present disclosure will be described in more detail below. Although exemplary examples of the present disclosure are shown, it should be understood that the present disclosure may be implemented in various forms, and should not be limited by the examples set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art.
Example 1:
This example of the present disclosure provided a method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material, including the following steps:

1) placing a graphite or graphene raw material in a plasma cleaning machine for plasma cleaning, wherein the plasma cleaning machine had an air pressure of 2 MPa and a power of 550-600 W, and the time for the plasma cleaning was 30 min;
2) taking preparation materials of an activator including the following components in percentage by weight: 15% of sulfuric acid, 0.1% of an OP-10 surfactant, 0.1% of sodium dodecyl sulfate, and the balance being water;
3) mixing the aforementioned components of the activator to prepare the activator, and continually cleaning the graphite or graphene raw material with the activator;
4) continually cleaning the graphite or graphene raw material with deionized water;
5) conducting a electroplating process on a surface of the graphite or graphene raw material twice to form a copper film layer;
6) continually cleaning the graphite or graphene raw material electroplated with the copper film layer on the surface thereof with deionized water;
7) firstly, soaking the graphite or graphene raw material plated with the copper film layer in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film on the copper film layer, and then putting into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film on the copper film layer to effectively prevent the copper film from color changing;
8) drying the graphite or graphene raw material electroplated with the copper film layer.

In the step 5), it included two electroplating procedures: firstly, the graphite or graphene raw material was subjected to primary electroplating with an electroplating solution; and secondly, the graphite or graphene raw material was subjected to secondary electroplating with the electroplating solution. The electroplating solution included the following components in percentage by weight: 5% of copper ions; 14% of sulfuric acid; 0.8% of a brightener; 0.06% of an adjuvant; 0.06% of a leveling agent; and the balance being water. During the electroplating process, pickling could be carried out at the same time, so that the flatness of the heat dissipation component was good.

Various process parameters of Example 1 were shown in the table below:

Electroplating process	Component name	Solution concentration	Temperature	Time
Activation	sulfuric acid	15%	25°C	3 minutes
	Surfactant A (OP-10)	0.10%
	sodium dodecyl sulfate	0.10%
Washing with pure water	deionized water		25°C	20 seconds
Pre-plating of copper	Copper ions	50 g/l	40°C	20 minutes
	sulfuric acid	14%
	Additive A (brightener)	0.80%
	Additive B (adjuvant)	0.06%
	Additive C (leveling agent)	0.06%
Electroplating of copper	Copper ions	50 g/l	40°C	15 minutes
	sulfuric acid	14%
	Additive A (brightener)	0.80%
	Additive B (adjuvant)	0.06%
	Additive C	0.06%
	(leveling agent)
Cleaning with pure water	deionized water		25°C	20 seconds
Protection 1	methyl benzotriazole	5g/l	25°C	20 seconds
Protection 2	cetylpyridinium bromide	0.5g/l	25°C	20 seconds
Drying	drying oven		80°C	2 minutes

Example 2

This example of the present disclosure provided a method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material, including the following steps:

1) placing a graphite or graphene raw material in a plasma cleaning machine for plasma cleaning, wherein the plasma cleaning machine had an air pressure of 2 MPa and a power of 550-600 W, and the time for the plasma cleaning was 30 min;
2) taking preparation materials of an activator including the following components in percentage by weight: 16% of sulfuric acid, 0.2% of an OP-10 surfactant, 0.2% of sodium dodecyl sulfate, and the balance being water;
3) mixing the aforementioned components of the activator to prepare the activator, and continually cleaning the graphite or graphene raw material with the activator;
4) continually cleaning the graphite or graphene raw material with deionized water;
5) conducting a electroplating process on a surface of the graphite or graphene raw material twice to form a copper film layer;
6) continually cleaning the graphite or graphene raw material electroplated with the copper film layer on the surface thereof with deionized water;
7) firstly, soaking the graphite or graphene raw material plated with the copper film layer in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film on the copper film layer, and then putting into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film on the copper film layer to effectively prevent the copper film from color changing;
8) drying the graphite or graphene raw material electroplated with the copper film layer.

In view of the above, compared with the prior art, the method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material as provided by the aforementioned examples has the following advantages. The graphite or graphene raw material is firstly placed in a plasma cleaning machine for plasma cleaning, and then the surface of graphite or graphene is treated with an activator compounded by sulfuric acid, the OP-10 surfactant and sodium dodecyl sulfate. Sulphuric acid can wash away oil stains from the graphite or graphene raw material, the OP-10 surfactant improves the smoothness of the surface of the graphite or graphene raw material, and sodium dodecyl sulfate increases the dispersibility of graphite or graphene and further increases the smoothness of the surface of the graphite or graphene raw material, so that the electroplated copper film layer has good binding quality and is uniform, which enhances the flexibility of the prepared heat dissipation component, and the surface of the heat dissipation component is not easy to generate creases, and the heat dissipation and acid and alkali resistance performances of the heat dissipation component are improved. After the copper film layer is formed on the graphite or graphene raw material by electroplating, the graphite or graphene raw material electroplated with the copper film layer is first soaked in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film on the copper film layer, and then put into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film on the copper film layer, which effectively prevents the copper film layer from color changing.

Claims

A method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material, comprising the following steps:
1) plasma cleaning a graphite or graphene raw material;

2) taking preparation materials of an activator comprising the following components in percentage by weight: 10-20% of sulfuric acid, 0.05-1% of an OP-10 surfactant, 0.05-1% of sodium dodecyl sulfate, and the balance being water;

3) mixing the aforementioned components of the activator to prepare the activator, and continually cleaning the graphite or graphene raw material with the activator;

4) continually cleaning the graphite or graphene raw material with deionized water;

5) conducting an electroplating process on a surface of the graphite or graphene raw material to form a copper film layer;

6) continually cleaning the graphite or graphene raw material electroplated with the copper film layer on the surface thereof with deionized water;

7) forming a protective film on the graphite or graphene raw material by soaking, comprising: the graphite or graphene raw material is firstly soaked in a 5 g/L methyl benzotriazole solution for 20-30 seconds to form a first layer of protective film, and then put into a 0.5 g/L cetylpyridinium bromide solution for 20-30 seconds to form a second layer of protective film; and

8) drying the graphite or graphene raw material electroplated with the copper film layer.
The method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material according to claim 1, wherein in the step 1), the graphite or graphene raw material is placed in a plasma cleaning machine for cleaning.
The method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material according to claim 1, wherein in the step 2), the activator comprises the following components in percentage by weight: 12-16% of sulfuric acid, 0.05-0.5% of the OP-10 surfactant, 0.05-0.5% of sodium dodecyl sulfate, and the balance being water.
The method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material according to claim 3, wherein in the step 2), the activator comprises the following components in percentage by weight: 15% sulfuric acid, 0.1% of the OP-10 surfactant, 0.1% of sodium dodecyl sulfate, and the balance being water.
The method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material according to claim 1, wherein in the step 5), the graphite or graphene raw material is subjected to the electroplating process twice with an electroplating solution, and the electroplating solution comprises the following components in percentage by weight: 5% of copper ions; 14% of sulfuric acid; 0.8% of a brightener; 0.06% of an adjuvant; 0.06% of a leveling agent; and the balance being water
The method for preparing a heat dissipation component with high flexibility made of a graphite or graphene material according to claim 5, wherein in the step 5), when the graphite or graphene raw material is electroplated with the electroplating solution for the first time, the temperature is 40 celsius degrees and the time is 20 minutes; and when the graphite or graphene raw material is electroplated with the electroplating solution for the second time, the temperature is 40 celsius degrees and the time is 15 minutes.