CN112622368A

CN112622368A - Low-stress heat conduction pad, preparation method thereof and electronic product

Info

Publication number: CN112622368A
Application number: CN202011498446.3A
Authority: CN
Inventors: 廖志盛; 李峰
Original assignee: Hangzhou Zhaoke Electronic Materials Co ltd
Current assignee: Hangzhou Zhaoke Electronic Materials Co ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2021-04-09
Anticipated expiration: 2040-12-17
Also published as: CN112622368B

Abstract

The application relates to the field of heat conduction materials, in particular to a low-stress heat conduction pad, a preparation method thereof and an electronic product. The preparation method of the heat conduction pad comprises the following steps: arranging protective layers on two surfaces of the heat-conducting silica gel layer; the protective layer is a glass fiber cloth layer and/or a polyimide film layer. Through set up glass fiber cloth layer and/or polyimide film layer on two surfaces at heat conduction silica gel layer, formed the support to heat conduction silica gel layer, even hardness shore00 also can use well at the very soft heat conduction silica gel layer between 1 ~ 6. And because the glass fiber cloth layers and/or the polyimide film layers are arranged on the two surfaces of the heat-conducting silica gel layer, the bending resistance of the heat-conducting silica gel layer is improved, the heat-conducting silica gel layer is prevented from being torn in the using process, and the using range is greatly expanded.

Description

Low-stress heat conduction pad, preparation method thereof and electronic product

Technical Field

The application relates to the field of heat conduction materials, in particular to a low-stress heat conduction pad, a preparation method thereof and an electronic product.

Background

Since chips, circuit boards, etc. are prone to generate heat, heat conductive pads are required to be provided in electronic products. Typically, a thermally conductive silicone sheet is used.

However, the conventional lowest hardness of the existing heat-conducting silicone sheet is shore 15, which limits the application range of the heat-conducting silicone sheet because the heat-conducting silicone sheet is too hard in use.

Disclosure of Invention

An object of the present invention is to provide a low-stress thermal pad, a method for manufacturing the same, and an electronic product, which are capable of providing a thermal pad with low hardness and convenient operation.

In a first aspect, the present application provides a method for manufacturing a thermal pad, including:

arranging protective layers on two surfaces of the heat-conducting silica gel layer; the protective layer is a glass fiber cloth layer and/or a polyimide film layer.

Through set up glass fiber cloth layer and/or polyimide film layer at two surfaces of heat conduction silica gel layer, formed the support to heat conduction silica gel layer, even heat conduction silica gel layer hardness is very low (shore 00 is between 1 ~ 6) also can use well. The double-sided support can improve the supporting force of the heat-conducting silica gel layer and solve the problem of high viscosity of low-hardness heat-conducting silica gel. And because two surfaces of the heat-conducting silica gel layer are provided with the glass fiber cloth layers and/or the polyimide film layers, the bending resistance of the heat-conducting silica gel layer is improved, the heat-conducting silica gel layer is prevented from being torn in the using process, and the using range is greatly expanded. This heat conduction pad can use shore00 at the heat conduction silica gel between 1 ~ 6 to guarantee that it has excellent support intensity, and viscosity is lower, make user convenient operation. Moreover, the heat conducting pad is thin in thickness, can meet the requirements of lightness and thinness of the existing electronic products, and is wide in application range.

In other embodiments of the present application, the step of disposing the protective layer on two surfaces of the heat conductive silicone layer includes:

and (4) carrying out composite molding on the protective layer and the heat-conducting silica gel layer in a rolling mode.

In other embodiments of the present application, the step of calendering comprises:

mixing and uniformly dispersing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil in parts by mass to obtain a first dispersing material;

mixing and uniformly dispersing the first dispersing material, 300-1900 parts of heat-conducting powder and 0.5-100 parts of flame-retardant auxiliary agent to obtain a second dispersing material;

and coating the second disperse material between the protective layers, and rolling and forming.

In other embodiments of the present application, the raw materials of the methyl vinyl silicone rubber include: one or more of methyl end-capping glue, vinyl end-capping glue and linear polydimethylsiloxane;

alternatively, the linear polydimethylsiloxane has a molecular weight of 45 to 80 ten thousand and a vinyl content of between 0.0% and 5%;

optionally, the vinyl silicone oil is selected from one or more of monovinyl-terminated polydimethylsiloxane, divinyl-terminated polydimethylsiloxane and methyl-terminated polydimethylsiloxane;

alternatively, the viscosity of the vinyl silicone oil is at 100-.

In other embodiments of the present application, the step of mixing and uniformly dispersing 2 to 30 parts of methyl vinyl silicone rubber and 8 to 70 parts of vinyl silicone oil to obtain a first dispersed material comprises:

mixing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil, and dispersing at high speed under a vacuum heating condition;

optionally, the linear velocity of dispersion is not less than 12m/s, the vacuum degree is 0.05-0.10 MPa, and the temperature is 130-150 ℃;

alternatively, the stirring time is 30-40 minutes.

In other embodiments of the present application, the heat conductive powder is selected from one or more of aluminum nitride, boron nitride, aluminum oxide, aluminum hydroxide, zinc oxide, and silicon carbide;

optionally, the flame retardant auxiliary agent is selected from one or more of aluminum hydroxide, aluminum oxide and magnesium oxide;

optionally, the flame retardant aid is spherical or spheroidal in shape.

In other embodiments of the present application, before the second bulk material is subjected to the calendaring step, the second bulk material and the auxiliary agent are uniformly mixed;

optionally, the auxiliary agent comprises, in parts by mass: 0.3-10 parts of mold release agent, 0.3-6 parts of processing aid, 2-15 parts of crosslinking aid, 0.3-3 parts of delay agent and 0.3-5 parts of catalyst;

optionally, the release agent is selected from one or more of a surfactant, hydroxyl linear polydimethylsiloxane and diphenyl silanediol;

optionally, the processing aid is selected from one or more of talcum powder, silicon dioxide and titanium dioxide;

optionally, the crosslinking assistant is selected from one or more of bis-tetra, bis-penta and hydrogen-containing silicone oil;

optionally, the retarder is ethynylcyclohexanol;

alternatively, the main active ingredient of the catalyst is metallic platinum.

In other embodiments of the present application, the fiberglass cloth layer is made of alkali-free fiberglass cloth, optionally, having a thickness of 0.033-0.082 mm;

the polyimide film layer is prepared by pyromellitic dianhydride and 4.4-diaminodiphenyl ether or resin; optionally, the thickness is 0.025-0.2 mm.

In a second aspect, the present application provides a thermal pad comprising:

a heat conductive silica gel layer; and

a protective layer; the protective layers are arranged on two surfaces of the heat-conducting silica gel layer; the protective layer is a glass fiber cloth layer and/or a polyimide film layer.

In other embodiments of the present application, the shore00 of the thermally conductive silica gel layer is between 1 and 6.

In a third aspect, the present application provides an electronic product including a thermal pad obtained by the method for manufacturing a thermal pad according to any one of the above embodiments; or the aforementioned thermal pad.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments.

Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

The inventor finds that the heat-conducting silica gel with the shore00 of 1-6 has excellent heat conductivity and can be applied to more use scenes. Therefore, the problem that the application scene of the heat-conducting silica gel is limited due to the fact that the heat-conducting silica gel is too hard in the prior art can be solved. However, the heat-conducting silica gel with the shore00 of 1-6 is very easy to deform due to too low hardness and too high viscosity, and the heat-conducting silica gel with the hardness is difficult to be made into a silica gel sheet, and is very inconvenient for a user to hold due to too high viscosity of the heat-conducting silica gel which is easy to deform during use.

The embodiment of the application provides a heat conduction pad, and this heat conduction pad can use shore00 heat conduction silica gel between 1 ~ 6 to guarantee that it has excellent support intensity, and viscosity is lower, make user convenient operation. Moreover, the heat conducting pad is thin in thickness, can meet the requirements of lightness and thinness of the existing electronic products, and is wide in application range.

Further, the heat conduction pad includes: heat conduction silica gel layer and inoxidizing coating. Further, the protective layer sets up two surfaces at heat conduction silica gel layer.

Further, the protective layer is a glass fiber cloth layer and/or a polyimide film layer.

Further, the shore00 of the heat-conducting silica gel layer is between 1 and 6.

Further optionally, the shore00 of the heat conductive silica gel layer is between 2 and 5.

Illustratively, the above-described thermally conductive silicone gel layer has a shore00 of 3, 4, or 5.

Through set up glass fiber cloth layer and/or polyimide film layer on two surfaces at heat conduction silica gel layer, formed the support to heat conduction silica gel layer, even hardness shore00 also can use well at the very soft heat conduction silica gel layer between 1 ~ 6. And because the glass fiber cloth layers and/or the polyimide film layers are arranged on the two surfaces of the heat-conducting silica gel layer, the bending resistance of the heat-conducting silica gel layer is improved, the heat-conducting silica gel layer is prevented from being torn in the using process, and the using range is greatly expanded.

In some embodiments, a method for manufacturing a thermal pad is provided, which can be used to manufacture the thermal pad provided in the above embodiments.

In some embodiments of the present application, the method for manufacturing a thermal pad includes: the protective layers are arranged on two surfaces of the heat-conducting silica gel layer.

Further, set up the step on two surfaces on heat conduction silica gel layer with the inoxidizing coating, include: and (4) carrying out composite molding on the protective layer and the heat-conducting silica gel layer in a rolling mode.

Further, the step of calendering comprises: mixing and uniformly dispersing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil in parts by mass to obtain a first dispersing material;

In some embodiments, the above method for preparing the thermal pad by calendering composition comprises the following steps:

and step S1, removing impurities from the heat-conducting powder.

Through carrying out the edulcoration to the heat conduction powder, can improve the compound effect of follow-up heat conduction powder and other raw materialss.

Further, the heat conducting powder is subjected to impurity removal in a high-temperature dehydration mode.

Further, the heat conducting powder is selected from one or more of aluminum nitride, boron nitride, aluminum oxide, aluminum hydroxide, zinc oxide and silicon carbide.

Illustratively, the above-mentioned heat conductive powder is aluminum nitride, boron nitride, aluminum oxide, aluminum hydroxide, zinc oxide, or silicon carbide; or the heat conducting powder is aluminum nitride and boron nitride; or the heat conducting powder is aluminum nitride, boron nitride and aluminum oxide; or the heat conducting powder is aluminum hydroxide, zinc oxide and silicon carbide.

And step S2, preparing a heat-conducting silica gel layer.

The preparation method of the heat-conducting silica gel layer comprises the following steps:

mixing and uniformly dispersing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil to obtain a first dispersing material;

and rolling and molding the second dispersing material to obtain the heat-conducting silica gel layer.

Further, the step of mixing and uniformly dispersing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil to obtain a first dispersed material comprises the following steps:

alternatively, the stirring time is 30-40 minutes.

In some embodiments of the present application, 2 to 30 parts of methyl vinyl silicone rubber and 8 to 70 parts of vinyl silicone oil are mixed and added into a high-speed dispersing machine or a planetary mixer, and a high-speed dispersing disk is added for high-speed dispersion.

Further optionally, the linear velocity of dispersion is 12-20 m/s, the vacuum degree is 0.06-0.09 MPa, and the temperature is 135-149 ℃.

Further optionally, the linear velocity of the dispersion is 13-19 m/s, the vacuum degree is 0.07-0.09 MPa, and the temperature is 136-148 ℃.

Illustratively, the linear velocity of the dispersion is 15m/s, the vacuum is 0.08MPa, and the temperature is 140 ℃.

Further, the raw materials of the methyl vinyl silicone rubber comprise: one or more of methyl end-capping glue, vinyl end-capping glue and linear polydimethylsiloxane.

Alternatively, the linear polydimethylsiloxane has a molecular weight of 45 to 80 ten thousand and a vinyl content of between 0.0% and 5%.

Further alternatively, the linear polydimethylsiloxane has a molecular weight of 46 to 79 ten thousand and a vinyl content of between 0.01% and 4%.

Illustratively, the molecular weight of the linear polydimethylsiloxane is 50 ten thousand with a vinyl content of 1%.

Further, the vinyl silicone oil is selected from one or more of monovinyl-terminated polydimethylsiloxane, divinyl-terminated polydimethylsiloxane and methyl-terminated polydimethylsiloxane.

Further, the viscosity of the vinyl silicone oil is 100-5000 cps.

Further optionally, the vinyl silicone oil has a viscosity of 110-.

Further optionally, the vinyl silicone oil has a viscosity of 120-4000 cps.

Illustratively, the vinyl silicone oil has a viscosity of 130cps, 200cps, 300cps, 400cps, 500cps, 600cps, 1000cps, 1500cps, 2500cps, 3000 cps.

And step S3, uniformly mixing the second dispersing material and the auxiliary agent.

Further, the auxiliary agent comprises the following components in parts by mass: 0.3-10 parts of mold release agent, 0.3-6 parts of processing aid, 2-15 parts of crosslinking aid, 0.3-3 parts of delay agent and 0.3-5 parts of catalyst;

further, the release agent is selected from one or more of a surfactant, hydroxyl linear polydimethylsiloxane and diphenyl silanediol.

In some embodiments, the surfactant is Silicone Oil surfactant.

Further, the processing aid is selected from one or more of talcum powder, silicon dioxide and titanium dioxide.

Further, the crosslinking assistant is selected from one or more of bis-tetra, bis-penta and hydrogen-containing silicone oil.

Further, the retarder is ethynylcyclohexanol.

Further, the main active ingredient of the catalyst is metallic platinum.

In some embodiments of the present application, the heat conductive powder prepared in step S1 is prepared in an amount of 300-1900 parts, the first dispersion material prepared in step S2 is prepared in an amount of 0.5-100 parts; 0.3-10 parts of mold release agent, 0.3-6 parts of processing aid, 2-15 parts of crosslinking aid, 0.3-3 parts of retarder and 0.3-5 parts of catalyst are mixed and uniformly dispersed to obtain second dispersed material.

Further, 1900 parts of the heat-conducting powder prepared in the step S1, 0.5-100 parts of the first dispersing material prepared in the step S2 and 0.5-100 parts of a flame-retardant auxiliary agent; 0.3-10 parts of mold release agent, 0.3-6 parts of processing aid, 2-15 parts of crosslinking aid, 0.3-3 parts of retarder and 0.3-5 parts of catalyst are mixed and stirred by a high-speed dispersion machine or a planetary stirrer.

And S4, forming the heat-conducting silica gel layer obtained in the step S3 and the protective layer into a whole.

Further, arranging the protective layers on two surfaces of the heat-conducting silica gel layer in a physical compounding mode; the protective layer is a glass fiber cloth layer and/or a polyimide film layer.

Further, set up the step on two surfaces on heat conduction silica gel layer through the mode of physics complex with the inoxidizing coating, include:

and stacking the protective layer and the heat-conducting silicon layer, and then compounding the protective layer and the heat-conducting silicon layer into a whole in a rolling mode.

In some embodiments of the present application, an 8-roll calender is adopted, the upper film is provided with the glass fiber cloth \ polyimide film and the PET release film, the lower film is provided with the glass fiber cloth \ polyimide film and the PET release film, and the lower film is rolled to obtain a product with a thickness required by a customer by adjusting the thickness at different intervals.

Further, the glass fiber cloth layer is made of alkali-free glass fiber cloth, optionally, with a thickness of 0.033-0.082 mm.

Further optionally, the glass fiber cloth layer has a thickness of 0.035-0.080 mm.

Further optionally, the glass fiber cloth layer has a thickness of 0.030-0.070 mm.

Illustratively, the fiberglass cloth layer has a thickness of 0.040mm, 0.050mm, or 0.060 mm.

Further, the polyimide film layer is made of pyromellitic dianhydride and 4, 4-diaminodiphenyl ether or resin; optionally, the thickness is 0.025-0.2 mm.

Further alternatively, the thickness of the polyimide film layer is 0.030 to 0.15 mm.

Further optionally, the thickness of the polyimide film layer is 0.050-0.10 mm.

Illustratively, the polyimide film layer thickness is 0.060mm, 0.080mm, 0.090 mm.

In some embodiments of the present application, the upper surface and the lower surface of the heat conducting pad are both provided with a glass fiber cloth layer.

In some embodiments of the present application, the upper surface and the lower surface of the thermal pad are both provided with a polyimide film layer.

In some embodiments of the present disclosure, the glass fiber cloth layer is disposed on the upper surface of the thermal pad, and the polyimide film layer is disposed on the lower surface of the thermal pad.

In some embodiments of the present disclosure, the glass fiber cloth layer is disposed on the lower surface of the thermal pad, and the polyimide film layer is disposed on the upper surface of the thermal pad.

The thicknesses of the glass fiber cloth layer and the polyimide film layer are selected according to actual needs. The number of the layers of the glass fiber cloth layer and the polyimide film layer may be selected and set as a plurality of layers according to actual needs.

Some embodiments of the present application also provide an electronic product including a thermal pad manufactured by the method for manufacturing a thermal pad provided in any one of the foregoing embodiments; or the aforementioned thermal pad.

The features and properties of the present application are described in further detail below with reference to examples:

example 1

Providing a heat conducting pad, which is prepared by the following steps:

(1) and removing impurities from the heat conducting powder.

And removing impurities by adopting a high-temperature dehydration mode. The heat conducting powder consists of aluminum nitride, boron nitride, aluminum oxide, aluminum hydroxide, zinc oxide and silicon carbide.

(2) And removing impurities from the heat conducting powder.

Mixing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil, adding the mixture into a high-speed dispersion machine or a planetary stirrer, and adding a high-speed dispersion disc to perform high-speed dispersion to obtain a first dispersion material.

The raw materials of the methyl vinyl silicone rubber comprise: methyl terminated glues, vinyl terminated glues and linear polydimethyl siloxane.

The molecular weight of the linear polydimethylsiloxane is 50 ten thousand, and the vinyl content is 4 percent.

(3) 800 parts of the heat conducting powder prepared in the step (1), 0.5 part of the first dispersing material prepared in the step (2) and 0.5 part of a flame retardant auxiliary agent; 0.3 part of mold release agent, 0.3 part of processing aid, 3 parts of crosslinking aid, 0.3 part of retarder and 0.3 part of catalyst are mixed and uniformly stirred and dispersed by a high-speed disperser or a planetary stirrer to obtain a second dispersing material.

(4) And adopting an 8-roller calender, laminating a polyimide film and a PET release film, discharging a lower film with glass fiber cloth and the PET release film, adjusting the thickness of different intervals, and calendering and molding the second dispersing material obtained in the step S3 and the protective layer to obtain a preset thickness product.

Example 2

The heat conducting pad is basically the same as the preparation step of the embodiment 1, except that in the step (4), the upper film is provided with the glass fiber cloth and the PET release film, and the lower film is provided with the polyimide film and the PET release film.

Example 3

The heat conducting pad is basically the same as the preparation step of the embodiment 1, except that in the step (4), the upper film is provided with the glass fiber cloth and the PET release film, and the lower film is provided with the glass fiber cloth and the PET release film.

Example 4

A thermal pad was provided, which was prepared substantially in the same manner as in example 1, except that in step (4), the upper film was provided with a polyimide film and a PET release film, and the lower film was provided with a polyimide film and a PET release film.

Example 5

Providing a heat conducting pad, which is basically the same as the preparation steps of the embodiment 1, except that in the step (3), 1900 parts of heat conducting powder, 100 parts of the first dispersing material prepared in the step (2) and 100 parts of a flame retardant auxiliary agent are used; 10 parts of mold release agent, 6 parts of processing aid, 2 parts of crosslinking aid, 3 parts of retarder and 5 parts of catalyst are mixed and then stirred and dispersed uniformly by a high-speed disperser or a planetary stirrer to obtain second dispersing material.

Example 6

Comparative example 1

Basically the same procedure as in example 1 was followed except that in step (4), only the top film was provided with the glass cloth and the PET release film.

Comparative example 2

A process substantially the same as that of example 1 except that in step (4), only the lower film was provided with polyimide glass and a PET release film was provided.

Examples of the experiments

The performance of the thermal pads having a thickness of 2.0mm as the test samples provided in examples 1 to 6 and comparative examples 1 to 2 was tested.

1. The compression rate detection step comprises:

1.1 taking a sample with a diameter of 27 mm;

1.2, testing by adopting a compressibility tester, and selecting 10\20\30PSI pressure;

1.3 recording the value according to the test result.

2. The step of detecting the thermal conductivity comprises:

2.1 sampling a sample with a diameter of 30 mm;

2.2, testing by adopting a DRL thermal conductivity tester to test the thermal conductivity coefficient;

2.3 recording the value according to the test result.

3. The detection step of the breakdown voltage comprises the following steps:

3.1 sampling 30mm by 60mm samples;

3.2, testing by adopting a breakdown voltage tester to test breakdown voltage resistance;

3.3 recording the value according to the test result.

4. The hardness detection step comprises the following steps:

4.1 sampling 60mm by 60mm samples;

4.2 testing the hardness by using a Shore oo hardness tester;

4.3 recording the value according to the test result.

The results are shown in Table 1.

TABLE 1

As can be seen from the above test results in table 1, the compressibility of the thermal pad prepared in the examples of the present application is significantly smaller than that of the comparative examples, and the thermal conductivity and the breakdown voltage satisfy the requirements. Therefore, the scheme of the application can keep small stress even if a very soft heat-conducting silica gel layer with the hardness Shore00 of 1-6 is adopted. And because the glass fiber cloth layers and/or the polyimide film layers are arranged on the two surfaces of the heat-conducting silica gel layer, the bending resistance of the heat-conducting silica gel layer is improved, the heat-conducting silica gel layer is prevented from being torn in the using process, and the using range is greatly expanded.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A preparation method of a low-stress heat conduction pad is characterized by comprising the following steps:

2. The method for producing a low-stress thermal pad according to claim 1,

set up the step on two surfaces on heat conduction silica gel layer with the inoxidizing coating, include:

and carrying out composite molding on the protective layer and the heat-conducting silicon adhesive layer in a rolling mode.

3. The method for producing a low-stress thermal pad according to claim 2,

the calendering step comprises:

4. The method according to claim 3, wherein the step of forming the low-stress thermal pad,

the raw materials of the methyl vinyl silicone rubber comprise: one or more of methyl end-capping glue, vinyl end-capping glue and linear polydimethylsiloxane;

optionally, the linear polydimethylsiloxane has a molecular weight of 45-80 ten thousand and a vinyl content of between 0.0% and 5%;

optionally, the viscosity of the vinyl silicone oil is between 100 and 5000 cps.

5. The method for producing a low-stress thermal pad according to claim 3 or 4,

the step of mixing and uniformly dispersing 2-30 parts of methyl vinyl silicone rubber and 8-70 parts of vinyl silicone oil to obtain a first dispersing material comprises the following steps:

alternatively, the stirring time is 30-40 minutes.

6. The method according to claim 3, wherein the step of forming the low-stress thermal pad,

the heat conducting powder is selected from one or more of aluminum nitride, boron nitride, aluminum oxide, aluminum hydroxide, zinc oxide and silicon carbide;

optionally, the flame retardant aid is spherical or spheroidal in shape.

7. The method according to claim 3, wherein the step of forming the low-stress thermal pad,

before the second dispersing material is subjected to the calendaring molding step, the second dispersing material and an auxiliary agent are uniformly mixed;

optionally, the delay agent is ethynylcyclohexanol;

optionally, the main active ingredient of the catalyst is metallic platinum.

8. The method for producing a low-stress thermal pad according to claim 1,

the glass fiber cloth layer is made of alkali-free glass fiber cloth, and optionally, the thickness is 0.033-0.082 mm;

9. A low stress thermal pad, comprising:

a heat conductive silica gel layer; and

a protective layer; the protective layers are arranged on two surfaces of the heat-conducting silica gel layer; the protective layer is a glass fiber cloth layer and/or a polyimide film layer; the shore00 of the heat-conducting silica gel layer is between 1 and 6.

10. An electronic product, comprising the thermal pad obtained by the method for preparing a low-stress thermal pad according to any one of claims 1 to 8; or the low stress thermal pad of claim 9.