阅读说明：本技术 一种柔性石墨烯电热膜制备工艺 (Preparation process of flexible graphene electrothermal film ) 是由 佘政国 于 2021-09-17 设计创作，主要内容包括：本发明提供了一种柔性石墨烯电热膜制备工艺,包括以下步骤：步骤1)：将氧化石墨烯粉末制备成浓度为0.05-0.09mg/ml的氧化石墨烯分散液；步骤2)：将所述氧化石墨烯分散液喷涂到基材上,烘干,形成氧化石墨烯薄膜,获得第一步成品；步骤3)：沿所述基材的长度方向,将银浆分别印刷在氧化石墨烯薄膜的两侧,形成两条第一银浆条,然后在两条第一银浆条之间,继续用银浆印刷形成至少两条第二银浆条,烘干,获得第二步成品；步骤4)：将铜箔覆盖在第二步成品中的第一银浆条上,然后通过5-20Mpa的压力将覆膜覆盖在所述铜箔的上表面,得到成品柔性石墨烯电热膜。本申请通过设置第一银浆条、第二银浆条,降低氧化石墨烯薄膜与银浆条交界处热量,提高产品的安全性能。(The invention provides a preparation process of a flexible graphene electrothermal film, which comprises the following steps: step 1): preparing graphene oxide powder into graphene oxide dispersion liquid with the concentration of 0.05-0.09 mg/ml; step 2): spraying the graphene oxide dispersion liquid on a substrate, and drying to form a graphene oxide film to obtain a first-step finished product; step 3): respectively printing silver paste on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing the silver paste between the two first silver paste strips to form at least two second silver paste strips, and drying to obtain a second-step finished product; step 4): and covering a copper foil on the first silver paste strip in the second-step finished product, and covering a covering film on the upper surface of the copper foil under the pressure of 5-20Mpa to obtain the finished product of the flexible graphene electrothermal film. This application reduces the heat of oxidation graphite alkene film and silver thick liquid strip juncture through setting up first silver thick liquid strip, second silver thick liquid strip, improves the security performance of product.)

1. A preparation process of a flexible graphene electrothermal film is characterized by comprising the following steps:

step 1): preparing graphene oxide powder into graphene oxide dispersion liquid with the concentration of 0.05-0.09 mg/ml;

step 2): spraying the graphene oxide dispersion liquid on a substrate, and drying to form a graphene oxide film to obtain a first-step finished product;

step 3): respectively printing silver pastes on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing the silver pastes between the two first silver paste strips to form at least two second silver paste strips, and drying to obtain a second-step finished product, wherein the intervals between the adjacent second silver paste strips are the same, and the widths of the first silver paste strips are larger than those of the second silver paste strips;

step 4): covering a copper foil on the first silver paste strip in the second step of the step 3), and covering a film on the upper surface of the copper foil under the pressure of 5-20Mpa to obtain the finished flexible graphene electrothermal film.

2. The preparation process of the flexible graphene electrothermal film according to claim 1, characterized in that: the drying temperature in the step 1) is 100-140 ℃.

3. The preparation process of the flexible graphene electrothermal film according to claim 2, characterized in that: the drying temperature in the step 2) is 100-170 ℃.

4. The preparation process of the flexible graphene electrothermal film according to claim 1, characterized in that: the coating film in the step 4) is a plastic film or a pre-coating film.

5. The preparation process of the flexible graphene electrothermal film according to claim 3, characterized in that: in the step 2), after more than two second silver paste strips are printed between two first silver paste strips, 8-10 second silver paste strips are printed by silver paste per centimeter continuously along the width direction of the substrate, and the intervals between the second silver paste strips are equal.

6. The preparation process of the flexible graphene electrothermal film according to claim 5, characterized in that: in the step 2), the edges of the first silver paste strips close to the edges of the substrate where the first silver paste strips are located are neat.

7. The preparation process of the flexible graphene electrothermal film according to claim 1, characterized in that: the specific preparation method of the graphene oxide dispersion liquid in the step 1) comprises the following steps:

and (3) freeze-drying the graphene oxide powder, and then dispersing the graphene oxide powder in a solvent to obtain the graphene oxide powder.

8. The preparation process of the flexible graphene electrothermal film according to claim 7, characterized in that: after the graphene oxide powder is freeze-dried, a dispersed solvent is any one of deionized water, ethanol, dimethyl sulfoxide and acetone.

9. The preparation process of the flexible graphene electrothermal film according to claim 7, characterized in that:

the graphene oxide dispersion liquid in the step 2) is sprayed on the substrate, and the specific operation method comprises the following steps:

and the contact angle between the substrate and the dispersion liquid drop of the graphene oxide dispersion liquid is 45 degrees, the substrate is heated at the temperature of 155 ℃ for 25min, and a graphene oxide film is formed on the surface of the substrate.

10. The preparation process of the flexible graphene electrothermal film according to claim 8, characterized in that: the thickness of the graphene oxide film is 3 um.

Technical Field

The invention relates to the technical field of electrothermal film preparation, in particular to a preparation process of a flexible graphene electrothermal film.

Background

In recent years, with the development of consumer upgrading and health industry, various flexible heating application products are continuously pushed out in the market, and particularly, graphene far infrared health related products are rapidly developed and are also accepted by consumers. The graphene far infrared health physiotherapy product can emit far infrared light waves, the wavelength range mainly falls in a range of 6-14um, far infrared rays in the range are easily absorbed by a human body and are called as 'life light waves', and the product is gradually seen by consumers.

And along with current electronic components's high integration, the healthy physiotherapy product of flexible graphite alkene far infrared generally all adopts graphite alkene flexible electric heat membrane as the electric heating element, and current graphite alkene flexible electric heat membrane adopts the electrically conductive thick liquids as the core layer that generates heat, then sets gradually corresponding protective layer, shielding layer on the surface, but the security is lower wholly.

Disclosure of Invention

The purpose of the invention is: the utility model provides a flexible graphite alkene electric heat membrane preparation technology, through set up many second silver thick liquid strips on two silver thick liquid strips, reduce the heat in boundary region to reduce graphite alkene electric heat membrane's resistance, and then solved current graphite alkene flexible electric heat membrane and had technical problem such as security performance.

The technical content of the invention is as follows:

a preparation process of a flexible graphene electrothermal film is characterized by comprising the following steps:

step 1): preparing graphene oxide powder into graphene oxide dispersion liquid with the concentration of 0.05-0.09 mg/ml;

step 2): spraying the graphene oxide dispersion liquid on a substrate, and drying to form a graphene oxide film to obtain a first-step finished product;

step 3): respectively printing silver pastes on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing the silver pastes between the two first silver paste strips to form at least two second silver paste strips, and drying to obtain a second-step finished product, wherein the intervals between the adjacent second silver paste strips are the same, and the widths of the first silver paste strips are larger than those of the second silver paste strips;

step 4): covering the copper foil on the first silver paste strip in the second step of the step 2), and covering the coated film on the upper surface of the copper foil through the pressure of 5-20Mpa to obtain a finished product.

Optionally, the drying temperature in the step 1) is 100-140 ℃.

Optionally, the drying temperature in the step 2) is 100-170 ℃.

Optionally, the coating film in the step 4) is a plastic film or a pre-coating film.

Optionally, in the step 2), after more than two second silver paste strips are printed between two first silver paste strips, 8 to 10 second silver paste strips are printed with silver paste per centimeter continuously along the width direction of the substrate, and the distances between the second silver paste strips are equal.

Optionally, in the step 2), edges of the first silver paste strips, which are close to the edges of the substrate, are neat.

Optionally, the specific preparation method of the graphene oxide dispersion liquid in the step 1) comprises: and (3) freeze-drying the graphene oxide powder, and then dispersing the graphene oxide powder in a solvent to obtain the graphene oxide powder.

Optionally, after the graphene oxide powder is freeze-dried, a dispersed solvent is any one of deionized water, ethanol, dimethyl sulfoxide and acetone.

Optionally, the graphene oxide dispersion liquid in step 2) is sprayed on the substrate, and the specific operation method is as follows:

and the contact angle between the substrate and the dispersion liquid drop of the graphene oxide dispersion liquid is 45 degrees, the substrate is heated at the temperature of 155 ℃ for 25min, and a graphene oxide film is formed on the surface of the substrate.

Optionally, the thickness of the graphene oxide film is 3 um.

By adopting the technical scheme, the invention mainly has the following technical effects:

the heat that this application technical scheme during operation produced can transmit first silver thick liquid strip, through set up the second silver thick liquid strip more than two between two first silver thick liquid strips, the width of first silver thick liquid strip is greater than the width of second silver thick liquid strip, reduces the resistance in boundary area, and the heat that produces can improve the security performance that corresponds the product to reduce the resistance of whole graphite alkene film, realize the low pressure and use.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view of a preparation process in the present application.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, the terms "upper", "lower", "front", and "rear", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention but do not require that the present invention must be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

The following further describes embodiments of the present invention with reference to the drawings.

Example 1:

referring to fig. 1, in the present embodiment, a preparation process of a flexible graphene electrothermal film is provided, in which 200mg of freeze-dried graphene oxide powder is dispersed in 4000ml of deionized water to prepare a 0.05mg/ml graphene oxide dispersion, and the graphene oxide dispersion is uniformly mixed;

spraying the graphene oxide dispersion liquid on a substrate in a spraying mode, wherein a spraying device can be used for spraying, when in spraying, the contact angle between the dispersion liquid drop of the graphene oxide dispersion liquid and the plane of the substrate is 45 degrees, heating the substrate at 155 ℃ for 25min, and then drying at 100 ℃ to form a graphene oxide film on the surface of the substrate, thereby obtaining a first-step finished product;

respectively printing silver paste on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing silver paste between the two first silver paste strips to form more than two second silver paste strips with the same interval, continuously printing 8 second silver paste strips per centimeter along the width direction of the substrate, wherein the intervals between the second silver paste strips are equal, and drying at 100 ℃ to obtain a second-step finished product;

and covering the copper foil on the first silver paste strip in the second-step finished product, and covering the covering film on the upper surface of the copper foil through the pressure of 5Mpa to obtain the finished product.

The planar thermal conductivity of the prepared graphene electrothermal film is 1206Wm^-1k^-1The electrical resistivity was 20 ohm/m, and the film had good flexibility and was broken by repeated bending.

Example 2:

the embodiment provides a preparation process of a flexible graphene electrothermal film, which comprises the steps of dispersing 200mg of freeze-dried graphene oxide powder into 2300ml of deionized water to prepare 0.09mg/ml of graphene oxide dispersion liquid, and uniformly mixing the graphene oxide dispersion liquid and the deionized water;

spraying the graphene oxide dispersion liquid on a substrate in a spraying mode, wherein a spraying device can be used for spraying, when in spraying, the contact angle between the dispersion liquid drop of the graphene oxide dispersion liquid and the plane of the substrate is 45 degrees, heating the substrate at 155 ℃ for 25min, and then drying at 140 ℃ to form a graphene oxide film on the surface of the substrate, thereby obtaining a first-step finished product;

respectively printing silver paste on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing the two first silver paste strips with the silver paste to form more than two second silver paste strips with the same interval, continuously printing 10 second silver paste strips per centimeter along the width direction of the substrate with the silver paste, wherein the intervals between the second silver paste strips are equal, and drying at 100 ℃ to obtain a second-step finished product;

and covering the copper foil on the first silver paste strip in the second-step finished product, and covering the covering film on the upper surface of the copper foil through the pressure of 20Mpa to obtain the finished product.

The planar thermal conductivity of the prepared graphene electrothermal film is 1475Wm^-1k^-1The electrical resistivity was 10 ohm/m, and the film had good flexibility and was broken by repeated bending.

Example 3:

the embodiment provides a preparation process of a flexible graphene electrothermal film, which comprises the steps of dispersing 200mg of freeze-dried graphene oxide powder into 2500ml of deionized water to prepare 0.08mg/ml graphene oxide dispersion liquid, and uniformly mixing the graphene oxide dispersion liquid and the deionized water;

spraying the graphene oxide dispersion liquid on a base material in a spraying mode, wherein a spraying device can be used for spraying, when in spraying, the contact angle between the dispersion liquid drop of the graphene oxide dispersion liquid and the plane of the base material is 45 degrees, heating the base material at 155 ℃ for 25min, and then drying at 120 ℃ to form a graphene oxide film on the surface of the base material, thereby obtaining a first-step finished product;

respectively printing silver pastes on two sides of the graphene oxide film along the length direction of the substrate to form two first silver paste strips, then continuously printing the two first silver paste strips with the silver pastes to form more than two second silver paste strips with the same interval, continuously printing 9 second silver paste strips per centimeter along the width direction of the substrate with the silver pastes, wherein the intervals between the second silver paste strips are equal, and drying at 150 ℃ to obtain a second-step finished product;

and covering the copper foil on the first silver paste strip in the second-step finished product, and covering the covering film on the upper surface of the copper foil through the pressure of 15Mpa to obtain the finished product.

The planar thermal conductivity of the prepared graphene electrothermal film is 1509Wm^-1k^-1The electrical resistivity was 30 ohm/m, and the film had good flexibility and was broken by repeated bending.

Comparative example 1:

current graphite alkene electric heat membrane includes graphite alkene conductive paste core layer that generates heat, graphite alkene conductive paste core layer lower surface that generates heat still spray has PET coating stratum basale, graphite alkene conductive paste core layer upper surface that generates heat still spray has the adhesive linkage, the adhesive linkage upper surface still bonds metal current-carrying strip conducting layer, metal current-carrying conducting layer upper surface still is provided with drenches the rete, the upper surface of drenching the rete still is provided with the PET tie coat, the upper surface of PET tie coat and the lower surface of PET coating base layer all spray have the insulating layer, the insulating layer surface all is equipped with the PET protective layer, PET protective layer surface is provided with the shielding layer. The thermal conductivity of the graphene electrothermal film is 809Wm^-1k^-1The resistivity was 1 ohm-meter.

The graphene electrothermal films prepared in the embodiments 1 to 3 have excellent performance in the aspect of thermal conductivity, higher resistivity value and good safety performance compared with the graphene electrothermal film prepared in the comparative embodiment 1.

It should be noted that the embodiments of the present invention are disclosed only as the preferred embodiments of the present invention, and are only used for illustrating the technical solutions of the present invention, not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art; the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the spirit and scope of the technical solutions of the embodiments of the present application.