Pretreatment production mode of graphene heat dissipation film coiled material

Abstract

The invention discloses a graphene heat dissipation film coiled material pretreatment production mode. The graphene heat dissipation film coiled material pretreatment production mode comprises the steps of coating, rolling, drying and pretreatment, and stripping and rolling. In the winding process, the high-temperature-resistant base material cloth is wound together, the high-temperature-resistant base material cloth can serve as a supporting layer, a film layer is fixedly supported, a supporting effect is achieved on the situation that the supporting performance of the coiled material is insufficient in the pretreatment process, and the high-temperature-resistant base material cloth can be used for producing the ultra-thin graphene heat conduction film coiled material. A fixed channel capable of overflowing gas is formed between layers of the coiled material after covering and rolling due to the existence of the high-temperature-resistant base material cloth, meanwhile, heat accumulation in the coiled material is effectively prevented, and a prevention effect is achieved on the smoldering phenomenon possibly generated in pretreatment.

Description

Technical Field

[0001] The invention relates to the technical field of graphene coil production, and in particular to a graphene heat dissipation film coil pretreatment production method. Background Art

[0002] In the era of electronic product technology, the power consumption of high-power electronic devices such as smart terminals has been improved with the performance, and the heat dissipation problem has become increasingly prominent. Graphene thermal conductive film is a thermal conductive film formed by directional self-assembly of graphene oxide and high-temperature sintering. During the heat treatment process, part of the bound water, oxygen-containing groups and impurity volatiles in the film material will generate a large amount of gas pressure during the volatilization process, which can easily cause the film material to expand and bubble. Therefore, the existing graphene thermal conductive films are all fired in sheets, and the generation of large bubbles is suppressed by covering during the firing process.

[0003] At present, the production method of large-scale preparation of graphite film thermal conductive film coils is mainly in the coating stage: in the stripping stage, due to the characteristics of graphene oxide, dense crust is easily formed during the drying process, resulting in uneven moisture content in the film material. The production efficiency is low (rate of about 1m / min), and the yield rate is poor during the stripping process because the stripping force changes with the degree of dryness of the surface layer; and during the storage of the coil, it is very easy for heat to accumulate in some areas, which cannot evaporate quickly and cause smoldering; during the pretreatment process, due to the increase in the thickness of the coil film, there is a large amount of moisture in the middle that cannot be dried quickly, thereby prolonging the storage and pretreatment time, resulting in the inability to improve production efficiency; during the pretreatment process, the degree of dryness inside and outside the coil is different, and a large amount of heat is easily accumulated inside, resulting in the coil explosion furnace situation has not been effectively improved. Therefore, improvements are needed. Summary of the invention

[0004] The present invention aims at the defects of uneven drying, smoldering and the like which easily occur in the film material during the coating stage in the prior art, and provides a new production method for pretreatment of graphene heat dissipation film coils.

[0005] In order to solve the above technical problems, the present invention is implemented by the following technical solutions:

[0006] A graphene heat dissipation film coil pretreatment production method comprises the following steps:

[0007] S1. Coating: taking a high temperature resistant substrate cloth as a coating support substrate, coating to form a graphene oxide film layer;

[0008] S2. Rolling: The coating layer is not peeled off and the coating layer is rolled up together with the high temperature resistant substrate cloth. The layers are fixed due to the presence of the high temperature resistant substrate cloth and the gas can overflow the fixed gap;

[0009] It can not only adjust the uniformity, but also increase the production efficiency in disguise. During the production process, the moisture content of the winding can be increased from 18% to about 35%, which nearly doubles the production coating speed.

[0010] When the thickness of the graphene oxide coil is less than 65um, it is easy to deform due to its poor support, which will limit the width of the coil. In the case of lamination and winding, the coated substrate is used as the support layer, and the film layer has a fixed support. This can solve and deal with the occurrence of such situations. It plays a supporting role in the case of insufficient support of the coil in the pretreatment, and can be used to produce ultra-thin graphene thermal conductive film coils. The original ultra-thin film layer has been unable to be mass-produced due to its weak support. After the overall lamination and winding, the production of coils below 10um has also been verified. The production of substrates below 10um can continue in this direction, and in the subsequent graphitization stage, the graphene oxide material becomes more supportive after dehydration, and can also be supported by its own strength after the substrate is peeled off. The original coil width is greatly limited by the thickness, which leads to the limitation of the film width, but after adding the coated substrate as a support layer, the original coil width increases from 180mm to 500mm, greatly improving the energy consumption utilization rate.

[0011] S3. Drying and pretreatment: The coiled material in step S2 is placed vertically in an oven together with the high temperature resistant substrate cloth for drying. Since the film layer and the substrate are rolled up together, and the high temperature resistant substrate cloth has a fixed air permeability and a uniform thickness, the graphene oxide film layer has a uniform rewetting efficiency and water volatilization efficiency. The high temperature resistant substrate cloth supports the coating layer that has not yet dried, and the heat generated and the oxygen elements generated by heating overflow from the fixed gap in the form of carbon dioxide and carbon monoxide;

[0012] S4. Peeling and rewinding: When the coiled material obtained in step S3 is placed vertically, the high temperature resistant substrate cloth is pulled out upward to complete the peeling of the high temperature resistant substrate cloth and the coiled material.

[0013] In the past, the production of graphene oxide layers was prone to uneven water loss (partially too dry or too wet), which made it impossible to peel off evenly. Now, by rolling up without peeling, a balanced state can be achieved by adjusting the temperature and humidity. The overdry parts can be re-moistened by absorbing water, while the over-wet parts can achieve the same effect by slowly letting the water out.

[0014] After the GO coil is laminated and rolled, the presence of the high-temperature resistant substrate cloth forms a fixed channel between the layers where gas can overflow. This effectively prevents heat accumulation inside the coil and plays a preventive role in the smoldering phenomenon that may occur during pretreatment.

[0015] During the pretreatment drying process, the heat generated and the oxygen elements generated by heating overflow in the form of carbon dioxide and carbon monoxide. The volatile gases can all overflow through the fixed gap. The original film explosion and heat accumulation are greatly improved due to the existence of the fixed gap. The pretreatment yield rate has increased from the original 70% to 95%.

[0016] Preferably, in the above-mentioned graphene heat dissipation film coil pretreatment production method, the material of the high temperature resistant substrate cloth is glass fiber.

[0017] The material of the high temperature resistant base cloth is glass fiber, which can better prevent the occurrence of smoldering.

[0018] As a preferred method, in the above-mentioned graphene heat dissipation film coil pretreatment production method, the air permeability of the high temperature resistant substrate cloth is less than 120L / m 2 *s, graphene oxide slurry viscosity>20000CP.

[0019] During the coating process, a high temperature resistant substrate cloth (glass fiber substrate) is used as the coating support substrate. After measurement, the air permeability is <120L / m 2 *s, when the viscosity of graphene oxide slurry is greater than 20000CP, the cloth base will not leak, which enhances the coating production efficiency, increases the coating speed, and improves the coating yield.

[0020] Preferably, in the above-mentioned graphene heat dissipation film coil pretreatment production method, Teflon coating is provided on the surfaces of the upper and lower sides of the high-temperature resistant substrate cloth.

[0021] After the graphene oxide coil is pretreated at high temperature, it shrinks and wrinkles at high temperature, and the cloth base can be easily delaminated from the graphene oxide coating. And due to the presence of Teflon coating on the surface, when the graphene oxide film material completes the pretreatment process, the cloth base can be easily delaminated from the graphene oxide film material laterally. And the substrate can be recycled and reused.

[0022] As a preferred method, in the above-mentioned graphene heat dissipation film coil pretreatment production method, when the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 14-15mm, and the air permeability is>100L / cm 2 / s, weight is 320g / m 2 .

[0023] As a preferred method, in the above-mentioned graphene heat dissipation film coil pretreatment production method, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 7-8mm, and the air permeability is>80L / cm 2 / s, weight is 220g / m 2 .

[0024] As a preferred method, in the above-mentioned graphene heat dissipation film coil pretreatment production method, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 2-3mm, and the air permeability is>80L / cm 2 / s, weight is 150g / m 2 . DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with specific embodiments, but they are not intended to limit the present invention:

[0026] Example 1

[0027] A graphene heat dissipation film coil pretreatment production method comprises the following steps:

[0028] S1. Coating: taking a high temperature resistant substrate cloth as a coating support substrate, coating to form a graphene oxide film layer;

[0029] S2. Rolling: The coating layer is not peeled off and the coating layer is rolled up together with the high temperature resistant substrate cloth. The layers are fixed due to the presence of the high temperature resistant substrate cloth and the gas can overflow the fixed gap;

[0030] S3. Drying and pretreatment: The coiled material in step S2 is placed vertically in an oven together with the high temperature resistant substrate cloth for drying. Since the film layer and the substrate are rolled up together, and the high temperature resistant substrate cloth has a fixed air permeability and a uniform thickness, the graphene oxide film layer has a uniform rewetting efficiency and water volatilization efficiency. The high temperature resistant substrate cloth supports the coating layer that has not yet dried, and the heat generated and the oxygen elements generated by heating overflow from the fixed gap in the form of carbon dioxide and carbon monoxide;

[0031] S4. Peeling and rewinding: When the coiled material obtained in step S3 is placed vertically, the high temperature resistant substrate cloth is pulled out upward to complete the peeling of the high temperature resistant substrate cloth and the coiled material.

[0032] Preferably, the high temperature resistant substrate cloth is made of glass fiber.

[0033] As a preferred option, the air permeability of the high temperature resistant base fabric is 120L / m 2 *s, the viscosity of graphene oxide slurry is 20000CP.

[0034] Preferably, the surfaces of the upper and lower sides of the high temperature resistant substrate cloth are both provided with Teflon coatings.

[0035] Example 2

[0036] Preferably, when the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 14mm and the air permeability is 100L / cm 2 / s, weight is 320g / m 2 .

[0037] The remaining steps refer to Example 1.

[0038] Example 3

[0039] Preferably, when the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 15mm and the air permeability is 100L / cm 2 / s, weight is 320g / m 2 .

[0040] The remaining steps refer to Example 1.

[0041] Example 4

[0042] Preferably, when the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 14mm and the air permeability is 110L / cm 2 / s, weight is 320g / m 2 .

[0043] The remaining steps refer to Example 1.

[0044] Example 5

[0045] Preferably, when the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 15mm and the air permeability is 110L / cm 2 / s, weight is 320g / m 2 .

[0046] The remaining steps refer to Example 1.

[0047] Example 6

[0048] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 7mm and the air permeability is 80L / cm 2 / s, weight is 220g / m 2 .

[0049] The remaining steps refer to Example 1.

[0050] Example 7

[0051] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 8mm and the air permeability is 80L / cm 2 / s, weight is 220g / m 2 .

[0052] The remaining steps refer to Example 1.

[0053] Example 8

[0054] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 7mm and the air permeability is 90L / cm 2 / s, weight is 220g / m 2 .

[0055] The remaining steps refer to Example 1.

[0056] Example 9

[0057] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 8mm and the air permeability is 90L / cm 2 / s, weight is 220g / m 2 .

[0058] The remaining steps refer to Example 1.

[0059] Example 10

[0060] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 2mm and the air permeability is 80L / cm 2 / s, weight is 150g / m 2 .

[0061] The remaining steps refer to Example 1.

[0062] Embodiment 11

[0063] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 3mm and the air permeability is 80L / cm 2 / s, weight is 150g / m 2 .

[0064] The remaining steps refer to Example 1.

[0065] Example 12

[0066] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 2mm and the air permeability is 90L / cm2 / s, weight is 150g / m 2 .

[0067] The remaining steps refer to Example 1.

[0068] Example 13

[0069] Preferably, when the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 3mm and the air permeability is 90L / cm 2 / s, weight is 150g / m 2 .

[0070] The remaining steps refer to Example 1.

[0071] In conclusion, the above is only a preferred embodiment of the present invention, and all equivalent changes and modifications made within the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A graphene heat dissipation film coil pretreatment production method, characterized in that: The steps include: S1. Coating: taking a high temperature resistant substrate cloth as a coating support substrate, coating to form a graphene oxide film layer; S2. Rolling: The coating layer is not peeled off and the coating layer is rolled up together with the high temperature resistant substrate cloth. The layers are fixed due to the presence of the high temperature resistant substrate cloth and the gas can overflow the fixed gap; S3. Drying and pretreatment: The coiled material in step S2 is placed vertically in an oven together with the high temperature resistant substrate cloth for drying. Since the film layer and the substrate are rolled up together, and the high temperature resistant substrate cloth has a fixed air permeability and a uniform thickness, the graphene oxide film layer has a uniform rewetting efficiency and water volatilization efficiency. The high temperature resistant substrate cloth supports the coating layer that has not yet dried, and the heat generated and the oxygen elements generated by heating overflow from the fixed gap in the form of carbon dioxide and carbon monoxide; S4. Peeling and rewinding: When the coiled material obtained in step S3 is placed vertically, the high temperature resistant substrate cloth is pulled out upward to complete the peeling of the high temperature resistant substrate cloth and the coiled material.

2. A graphene heat dissipation film coil pretreatment production method according to claim 1, characterized in that: The material of the high temperature resistant base cloth is glass fiber.

3. A graphene heat dissipation film coil pretreatment production method according to claim 2, characterized in that: The air permeability of high temperature resistant base fabric is less than 120L / m 2 *s, graphene oxide slurry viscosity>20000CP.

4. A graphene heat dissipation film coil pretreatment production method according to claim 3, characterized in that: The surfaces of the upper and lower sides of the high temperature resistant base cloth are both provided with Teflon coatings.

5. A graphene heat dissipation film coil pretreatment production method according to claim 4, characterized in that: When the target graphene oxide substrate thickness is 30um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 14-15mm and the air permeability is >100L / cm 2 / s, weight is 320g / m 2 .

6. A graphene heat dissipation film coil pretreatment production method according to claim 4, characterized in that: When the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 7-8mm and the air permeability is >80L / cm 2 / s, weight is 220g / m 2 .

7. A graphene heat dissipation film coil pretreatment production method according to claim 4, characterized in that: When the target graphene oxide substrate thickness is 20um and the water content is 35%, the thickness of the high temperature resistant substrate cloth is 2-3mm and the air permeability is >80L / cm 2 / s, weight is 150g / m 2 .