Film with heat dissipation structure and manufacturing method thereof

Abstract

The present invention discloses a film with a heat dissipation structure and a manufacturing method thereof. The film comprises a first low-temperature silver paste layer and a P-type ink layer thereon forming a first inner core, a second low-temperature silver paste layer and an N-type ink layer thereon forming a second inner core, a first thermal insulation ink layer being sandwiched between the first inner core and the second inner core, a third low-temperature silver paste layer covering the first and second inner cores and the first thermal insulation ink layer to form an overall inner core, upper and lower thermally conductive insulating silicone cloths covering the upper and lower sides of the overall inner core, and second and third thermal insulation ink layers covering the left and right sides of the overall inner core. The manufacturing method comprises the following steps of firstly forming the first, second and third thermal insulation ink layers, the first and second low-temperature silver paste layers, the P-type ink layer, the N-type ink layer and the third low-temperature silver paste layer on the lower thermally conductive insulating silicone cloth in sequence by printing, heating and curing, and finally affixing the thermally conductive insulating silicone cloth on the upper surface of the third low-temperature silver paste layer. The heat dissipation temperature of the film manufactured by the present invention can be as low as 0 to 10°C.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal conductive interface materials, and in particular to a film with a heat dissipation structure and a manufacturing method thereof. Background Art

[0002] As electronic products become smaller, lighter, and perform better, the heat generated by electronic components continues to increase. How to effectively and quickly transfer the large amount of heat generated to the outside of the product while reducing its weight has become an important issue in electronic product design.

[0003] To address heat dissipation issues in electronic products, heat dissipation materials can be installed to dissipate heat from the heat source. Traditional heat dissipation materials, such as thermal pads, thermal grease, thermal gel, two-component thermal caulking materials, epoxy thermal adhesive, and acrylic thermal adhesive, all transfer heat from the heat source to the surrounding environment. However, the lowest heat dissipation temperature cannot be lower than the ambient temperature, resulting in low thermal efficiency. Furthermore, thermally conductive materials occupy a large space within consumer electronics, which is inconsistent with the trend toward miniaturization of consumer electronics. Summary of the Invention

[0004] In order to make up for the above shortcomings, the present invention provides a film with a heat dissipation structure and a method for manufacturing the same. The film with a heat dissipation structure manufactured by this method can achieve multiple functions of high thermal conductivity and miniaturization, and can be applied to lightweight new energy vehicles, hard disks, optical communications, consumer electronics and other fields.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a film with a heat dissipation structure, including a first thermal insulation insulating ink layer, a second thermal insulation insulating ink layer, a third thermal insulation insulating ink layer, a P-type ink layer, an N-type ink layer, an upper thermal conductive insulating silicone cloth, a lower thermal conductive insulating silicone cloth, a first low-temperature silver paste layer, a second low-temperature silver paste layer and a third low-temperature silver paste layer, the first low-temperature silver paste layer for connecting the positive electrode is fixedly stacked with a P-type ink layer on the upper surface, and the second low-temperature silver paste layer for connecting the negative electrode is fixedly stacked with an N-type ink layer on the surface, the first low-temperature silver paste layer and the P-type ink layer thereon form a first inner core, the second low-temperature silver paste layer and the N-type ink layer thereon form a second inner core, and the upper and lower sides of the first thermal insulation insulating ink layer are aligned and fixedly clamped between the first inner core and the second core. A third low-temperature silver paste layer is fixedly stacked on the upper surfaces of the P-type ink layer, the N-type ink layer, and the first thermal insulation ink layer. The first inner core, the second inner core, the first thermal insulation ink layer, and the third low-temperature silver paste layer together form an integral inner core. The upper and lower thermally conductive insulating silicone cloths are fixedly stacked on the lower two sides of the integral inner core, completely covering them. The second and third thermal insulation ink layers are fixedly stacked on the left and right sides of the integral inner core, completely covering them. The overall thickness of this film is 0.03-1mm. Its heat dissipation principle is mainly based on the Peltier effect of semiconductor materials. When direct current passes through a galvanic couple formed by two different semiconductor materials in series, heat is absorbed and released at both ends of the galvanic couple, achieving the purpose of cooling. The upper and lower thermally conductive insulating silicone cloths serve as thermal conductors and insulators; the first, second, and third thermal insulation ink layers serve as thermal insulation and insulation; and the first, second, and third low-temperature silver paste layers serve as electrical conductors and thermal conductors.

[0006] As a further improvement of the present invention, the upper ends of the second thermal insulation insulating ink layer and the third thermal insulation insulating ink layer are completely covered and fixedly stacked on both side surfaces of the upper thermally conductive insulating silicone cloth, and the lower ends of the second thermal insulation insulating ink layer and the third thermal insulation insulating ink layer are completely covered and fixedly stacked on both side surfaces of the lower thermally conductive insulating silicone cloth, and the upper and lower ends of the second thermal insulation insulating ink layer and the third thermal insulation insulating ink layer are respectively aligned and connected with the surfaces of the upper and lower thermally conductive insulating silicone cloths.

[0007] A method for manufacturing a thin film with a heat dissipation structure, the specific steps are as follows:

[0008] Step 1: Printing thermal insulation ink on the lower thermal conductive insulating silicone cloth and heating and curing it to form a first thermal insulation ink layer, a second thermal insulation ink layer and a third thermal insulation ink layer;

[0009] Step 2: Printing low-temperature silver paste on the lower thermally conductive insulating silicone cloth and heating and curing it to form a first low-temperature silver paste layer located between the first thermal insulating ink layer and the second thermal insulating ink layer, and a second low-temperature silver paste layer located between the first thermal insulating ink layer and the third thermal insulating ink layer;

[0010] Step 3: Printing P-type ink on the surface of the first low-temperature silver paste layer, printing N-type ink on the surface of the second low-temperature silver paste layer, heating and curing to form a P-type ink layer and an N-type ink layer;

[0011] Step 4: Printing low-temperature silver paste on the upper surfaces of the P-type ink layer, the N-type ink layer, and the first thermal insulation ink layer and heating and curing them to form a third low-temperature silver paste layer;

[0012] Step 5: Attach thermally conductive insulating silicone cloth to the upper surface of the third low-temperature silver paste layer.

[0013] As a further improvement of the present invention, the P-type ink includes the following components in mass percentage: 5% to 90% bismuth telluride doped with antimony, 6.9% to 90% silver powder, 1% to 30% epoxy resin, 0.1% to 30% curing agent, 1% to 30% solvent and 1% to 10% additives; the N-type ink includes the following components in mass percentage: 5% to 90% bismuth telluride doped with selenium, 6.9% to 90% silver powder, 1% to 30% epoxy resin, 0.1% to 30% curing agent, 1% to 30% solvent and 1% to 10% additives.

[0014] As a further improvement of the present invention, the purity of the bismuth telluride doped with antimony and the bismuth telluride doped with selenium is above 99.99, and the particle size D50 is 0.5-30 μm.

[0015] As a further improvement of the present invention, the silver powder is flaky silver powder with a particle size D50 of 0.1-40 μm.

[0016] As a further improvement of the present invention, the epoxy resin is selected from at least one of aliphatic epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin and core-shell epoxy resin, and core-shell epoxy resin is more preferred.

[0017] As a further improvement of the present invention, the curing agent is selected from one of 2-ethyl 4-methylimidazole, imidazole, 4-methylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, dicyandiamide and 2-methylimidazole curing agents, and dicyandiamide curing agent is more preferred.

[0018] As a further improvement of the present invention, the solvent is selected from one of acetone, MIBK, 2-(2-ethoxyethoxy)ethyl acetate and γ-butyrolactone, and more preferably γ-butyrolactone and 2-(2-ethoxyethoxy)ethyl acetate.

[0019] As a further improvement of the present invention, the additive is selected from at least one of acetic acid, propionic acid, acetamide, propionamide, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, diamino functional silane and 3-aminopropyltriethoxysilane.

[0020] The beneficial technical effects of the present invention are as follows: the present invention is mainly based on the Peltier effect of semiconductor materials. When direct current passes through a galvanic couple formed by two different semiconductor materials connected in series, heat can be absorbed and released at both ends of the galvanic couple, respectively, to achieve the purpose of cooling. The thermally conductive insulating silicone cloth plays a role in heat conduction and insulation; the thermally insulating insulating ink plays a role in heat insulation and insulation; the low-temperature silver paste plays a role in electricity conduction and heat conduction. The thin film material obtained by the present invention has high thermal conductivity efficiency, and the heat dissipation temperature can be as low as 0-10°C. Moreover, due to its thin film structure, it can be used in lightweight new energy vehicles, hard disks, optical communications, consumer electronics and other places with high heat generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure principle of the film with heat dissipation structure of the present invention.

[0022] Lower thermal conductive insulating silicone cloth---1 Upper thermal conductive insulating silicone cloth---2

[0023] The first thermal insulation ink layer---3 The second thermal insulation ink layer---4

[0024] The third thermal insulation ink layer---5 The first low-temperature silver paste layer---6

[0025] Second low-temperature silver paste layer---7 Third low-temperature silver paste layer---8

[0026] P-type ink layer---9 N-type ink layer---10

[0027] Heat absorbing end---11 DETAILED DESCRIPTION

[0028] In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the specific implementation methods of the present invention are further described in detail below in conjunction with specific examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0029] Embodiment: A film with a heat dissipation structure comprises a first heat-insulating insulating ink layer, a second heat-insulating insulating ink layer, a third heat-insulating insulating ink layer, a P-type ink layer, an N-type ink layer, an upper heat-conducting insulating silicone cloth, a lower heat-conducting insulating silicone cloth, a first low-temperature silver paste layer, a second low-temperature silver paste layer and a third low-temperature silver paste layer, wherein the upper surface of the first low-temperature silver paste layer for connecting the positive electrode is fixedly stacked with a P-type ink layer, and the surface of the second low-temperature silver paste layer for connecting the negative electrode is fixedly stacked with an N-type ink layer, the first low-temperature silver paste layer and the P-type ink layer thereon form a first inner core, the second low-temperature silver paste layer and the N-type ink layer thereon form a second inner core, the upper and lower sides of the first heat-insulating insulating ink layer are aligned and fixedly clamped between the first inner core and the second inner core, and the third low-temperature silver paste layer is fixedly stacked with a P-type ink layer. The film is fixedly stacked on the upper surfaces of the P-type ink layer, N-type ink layer, and first thermal insulation ink layer. The first inner core, second inner core, first thermal insulation ink layer, and third low-temperature silver paste layer together form a monolithic inner core. The upper and lower thermally conductive insulating silicone cloths are completely stacked on the lower two sides of the monolithic inner core, while the second and third thermal insulation ink layers are completely stacked on the left and right sides of the monolithic inner core. The film has an overall thickness of 0.03-1mm. Its heat dissipation principle is primarily based on the Peltier effect of semiconductor materials. When direct current passes through a galvanic couple formed by two different semiconductor materials in series, heat is absorbed and released at both ends of the galvanic couple, achieving the purpose of cooling. The upper and lower thermally conductive insulating silicone cloths serve as thermal conductors and insulators; the first, second, and third thermal insulation ink layers serve as thermal insulation and insulation; and the first, second, and third low-temperature silver paste layers serve as electrical conductors and thermal conductors.

[0030] The upper ends of the second thermal insulation ink layer and the third thermal insulation ink layer are completely covered and fixedly stacked on both sides of the upper thermally conductive insulating silicone cloth, and the lower ends of the second thermal insulation ink layer and the third thermal insulation ink layer are completely covered and fixedly stacked on both sides of the lower thermally conductive insulating silicone cloth, and the upper and lower ends of the second thermal insulation ink layer and the third thermal insulation ink layer are aligned and connected with the surfaces of the upper and lower thermally conductive insulating silicone cloths respectively.

[0031] A method for manufacturing a thin film with a heat dissipation structure, the specific steps are as follows:

[0032] Step 1: Printing thermal insulation ink on the lower thermal conductive insulating silicone cloth and heating and curing it to form a first thermal insulation ink layer, a second thermal insulation ink layer and a third thermal insulation ink layer;

[0033] Step 2: Printing low-temperature silver paste on the lower thermally conductive insulating silicone cloth and heating and curing it to form a first low-temperature silver paste layer located between the first thermal insulating ink layer and the second thermal insulating ink layer, and a second low-temperature silver paste layer located between the first thermal insulating ink layer and the third thermal insulating ink layer;

[0034] Step 3: Printing P-type ink on the surface of the first low-temperature silver paste layer, printing N-type ink on the surface of the second low-temperature silver paste layer, heating and curing to form a P-type ink layer and an N-type ink layer;

[0035] Step 4: Printing low-temperature silver paste on the upper surfaces of the P-type ink layer, the N-type ink layer, and the first thermal insulation ink layer and heating and curing them to form a third low-temperature silver paste layer;

[0036] Step 5: Attach thermally conductive insulating silicone cloth to the upper surface of the third low-temperature silver paste layer.

[0037] In each of the above steps, the heating and curing temperature is 120° C. to 130° C., and the heating and curing time is 15 minutes to 1 hour.

[0038] The raw materials and reagents used are all commercially available. The raw materials used for the P-type ink and the N-type ink are as follows:

[0039] Bismuth telluride doped with antimony (99.99 or above) was purchased from Sichuan Gaochun;

[0040] Bismuth telluride doped with selenium (99.99 or above) was purchased from Sichuan Gaochun;

[0041] Flake silver powder-1: FA-S-18, purchased from Dowa;

[0042] Flake silver powder-2: FA-S-10, purchased from Dowa;

[0043] Flake silver powder-3: FA-S-15, purchased from Dowa;

[0044] Flake silver powder-4: FA-2-3, purchased from Dowa;

[0045] Flake silver powder-5: FA-S-13, purchased from Dowa;

[0046] Core-shell structure epoxy resin-1: MX153, purchased from Zhonghua;

[0047] Core-shell structure epoxy resin-2: MX125, purchased from Zhonghua;

[0048] Bisphenol A epoxy resin: Epiclon 830CRP, purchased from DIC;

[0049] Dicyandiamide curing agent-1: DYHARD 100S, purchased from AlzChem;

[0050] Dicyandiamide curing agent-2: DDA-5, purchased from AlzChem;

[0051] γ-Butyrolactone (solvent), Aladdin;

[0052] Acetic acid (additive), purchased from Aladdin;

[0053] Propionic acid (additive), purchased from Aladdin;

[0054] P-type ink and N-type ink were prepared by mixing according to the recipes of the examples in Table 1 and Table 2 below:

[0055] Table 1 shows the dosage of each component of the P-type ink formula of Examples 1-9 (unit: mass percentage)

[0056]

[0057]

[0058] Table 2 shows the dosage of each component of the N-type ink formula of Examples 1-9 (unit: mass percentage)

[0059]

[0060]

[0061] Using the P-type ink and N-type ink prepared in Examples 1-9, a film with a heat dissipation structure was prepared according to the aforementioned method for preparing a film with a heat dissipation structure. The lower thermally conductive insulating silicone cloth of the film was attached to a heating element (temperature of 80-150° C.), and the temperature of the heat absorbing end located on the upper thermally conductive insulating silicone cloth side of the film was measured, as shown in Table 3 below:

[0062] Table 3 shows the test results of the heat-absorbing end temperature of the films with heat dissipation structures prepared in Examples 1-9:

[0063] Films of Examples Heat absorption end temperature (℃) Example 1 3 Example 2 8 Example 3 5 Example 4 6 Example 5 5 Example 6 6 Example 7 8 Example 8 7 Example 9 5

[0064] One side of the conventional thermal conductive material is attached to a heating element (temperature 80-150°C), and the temperature of the heat absorbing end on the other side of the conventional thermal conductive material is measured as shown in Table 4 below:

[0065] Table 4 shows the temperature test results of the heat absorbing end of a conventional thermal conductive material:

[0066] Conventional thermal conductive materials Heat absorption end temperature (℃) thermal pads ＞25 thermal grease ＞25 Thermally conductive gel ＞25 Two-component thermally conductive gap filling material ＞25 Epoxy thermal adhesive ＞25 Acrylic thermal adhesive ＞25

[0067] From the data measured in Tables 3 and 4, it can be seen that the films obtained in Examples 1 to 9 of the present invention have excellent thermal conductivity, and the temperatures at the heat absorbing ends are all less than 25°C. The temperatures at the heat absorbing ends of conventional thermal conductive materials are all greater than 25°C. It can be seen that the films with heat dissipation structures obtained in the present invention have great advantages over conventional thermal conductive materials.

[0068] The above are only some preferred embodiments of the present invention, and the present invention is not limited to the contents of the embodiments. For those skilled in the art, various changes and modifications can be made within the scope of the technical solution of the present invention, and any changes and modifications made are within the scope of protection of the present invention.

Claims

1. A film with a heat dissipation structure, characterized in that: The invention comprises a first thermal insulation insulating ink layer, a second thermal insulation insulating ink layer, a third thermal insulation insulating ink layer, a P-type ink layer, an N-type ink layer, an upper thermal conductive insulating silicone cloth, a lower thermal conductive insulating silicone cloth, a first low-temperature silver paste layer, a second low-temperature silver paste layer and a third low-temperature silver paste layer, wherein the upper surface of the first low-temperature silver paste layer for connecting the positive electrode is fixedly stacked with a P-type ink layer, the surface of the second low-temperature silver paste layer for connecting the negative electrode is fixedly stacked with an N-type ink layer, the first low-temperature silver paste layer and the P-type ink layer thereon form a first inner core, the second low-temperature silver paste layer and the N-type ink layer thereon form a second inner core, the first insulation The fixed clamp aligned on the upper and lower sides of the thermal insulation ink layer is arranged between the first inner core and the second inner core, and the third low-temperature silver paste layer is fixedly stacked on the upper surface of the P-type ink layer, the N-type ink layer and the first thermal insulation insulation ink layer. The first inner core, the second inner core, the first thermal insulation insulation ink layer and the third low-temperature silver paste layer together form an integral inner core. The upper thermal conductive insulating silicone cloth and the lower thermal conductive insulating silicone cloth are respectively completely covered and fixedly stacked on the lower two side surfaces of the integral inner core. The second thermal insulation insulation ink layer and the third thermal insulation insulation ink layer are respectively completely covered and fixedly stacked on the left and right side surfaces of the integral inner core.

2. The film with a heat dissipation structure according to claim 1, wherein: The upper ends of the second thermal insulation ink layer and the third thermal insulation ink layer are completely covered and fixedly stacked on both sides of the upper thermally conductive insulating silicone cloth, and the lower ends of the second thermal insulation ink layer and the third thermal insulation ink layer are completely covered and fixedly stacked on both sides of the lower thermally conductive insulating silicone cloth, and the upper and lower ends of the second thermal insulation ink layer and the third thermal insulation ink layer are aligned and connected with the surfaces of the upper and lower thermally conductive insulating silicone cloths respectively.

3. A method for manufacturing a thin film with a heat dissipation structure according to claim 1, characterized in that: Specific steps as follows: Step 1: Printing thermal insulation ink on the lower thermal conductive insulating silicone cloth and heating and curing it to form a first thermal insulation ink layer, a second thermal insulation ink layer and a third thermal insulation ink layer; Step 2: Printing low-temperature silver paste on the lower thermally conductive insulating silicone cloth and heating and curing it to form a first low-temperature silver paste layer located between the first thermal insulating ink layer and the second thermal insulating ink layer, and a second low-temperature silver paste layer located between the first thermal insulating ink layer and the third thermal insulating ink layer; Step 3: Printing P-type ink on the surface of the first low-temperature silver paste layer, printing N-type ink on the surface of the second low-temperature silver paste layer, heating and curing to form a P-type ink layer and an N-type ink layer; Step 4: Printing low-temperature silver paste on the upper surfaces of the P-type ink layer, the N-type ink layer, and the first thermal insulation ink layer and heating and curing them to form a third low-temperature silver paste layer; Step 5: Attach thermally conductive insulating silicone cloth to the upper surface of the third low-temperature silver paste layer.

4. The method for manufacturing a thin film with a heat dissipation structure according to claim 3, wherein: The P-type ink includes the following components in mass percentage: 5% to 90% bismuth telluride doped with antimony, 10% to 90% silver powder, 1% to 30% epoxy resin, 0.1% to 30% curing agent, 1% to 30% solvent and 1% to 10% additives; the N-type ink includes the following components in mass percentage: 5% to 90% bismuth telluride doped with selenium, 10% to 90% silver powder, 1% to 30% epoxy resin, 0.1% to 30% curing agent, 1% to 30% solvent and 1% to 10% additives.

5. The method for manufacturing a thin film with a heat dissipation structure according to claim 4, wherein: The bismuth telluride doped with antimony and the bismuth telluride doped with selenium have a purity of 99.99 or higher, and a particle size D50 of 0.5-30 μm.

6. The method for manufacturing a thin film with a heat dissipation structure according to claim 4, wherein: The silver powder is flaky silver powder with a particle size D50 of 0.1-40 μm.

7. The method for manufacturing a thin film with a heat dissipation structure according to claim 4, wherein: The epoxy resin is selected from at least one of aliphatic epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin and core-shell epoxy resin.

8. The method for manufacturing a thin film with a heat dissipation structure according to claim 4, wherein: The curing agent is selected from one of 2-ethyl 4-methylimidazole, imidazole, 4-methylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, dicyandiamide and 2-methylimidazole curing agents.

9. The method for manufacturing a thin film having a heat dissipation structure according to claim 4, wherein: The solvent is selected from one of acetone, MIBK, 2-(2-ethoxyethoxy)ethyl acetate and gamma-butyrolactone.

10. The method for manufacturing a thin film with a heat dissipation structure according to claim 4, wherein: The additive is selected from at least one of acetic acid, propionic acid, acetamide, propionamide, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, diamino functional silane and 3-aminopropyltriethoxysilane.

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