KR102116558B1 - Thermal diffusion sheet and manufacturing method for thereof - Google Patents

Abstract

The present invention relates to a heat-diffusion sheet and a method for manufacturing the same, and more particularly, to a heat-diffusion sheet and a method for manufacturing the heat-diffusion sheet that is disposed adjacent to the heating element and can effectively dissipate heat transferred from the heating element.

Description

Heat diffusion sheet and its manufacturing method {THERMAL DIFFUSION SHEET AND MANUFACTURING METHOD FOR THEREOF}

The present invention relates to a heat-diffusion sheet and a method for manufacturing the same, and more particularly, to a heat-diffusion sheet and a method for manufacturing the heat-diffusion sheet that is disposed adjacent to the heating element and can effectively dissipate heat transferred from the heating element.

Portable terminals such as mobile phones, tablet PCs, notebook PCs, and PDAs are equipped with antennas for realizing near field communication (NFC), wireless charging, or other functions. In addition, batteries are provided for power supply in electric vehicles and portable terminals, and display elements are installed in display panels such as TVs, laptops, and monitors.

Components such as antennas, batteries, and display elements generate heat during operation, and when the corresponding components (hereinafter, heating elements) such as antennas, batteries, and display elements are overheated or heat generated is transferred to other electronic components, the performance of the components There is a problem that the reliability of the product may be lowered by causing the fall or the failure of a component.

Accordingly, a heat diffusion sheet is used to diffuse heat generated from the heating element and radiate heat to the outside. Referring to FIG. 1, conventionally, an adhesive, graphite, adhesive and PET film (PET film) are used. ) Were sequentially stacked, and the heat spreading sheet of the laminated structure bonded together was disposed around the heating element to dissipate heat generated from the heating element.

On the other hand, graphite has excellent thermal conductivity and was used as a main heat dissipation composition for heat-diffusion sheets. Graphite easily breaks and cracks, so its surface is easily damaged, and a problem occurs that damaged powders electrically affect electronic components. Did. In addition, graphite is produced by sintering a powder body, and there is a problem in that bonding with the pressure-sensitive adhesive is not smooth and thus the binding power is poor.

As described above, a PET film was additionally laminated on one surface of the graphite to prevent cracking, breakage, and powder flying (see FIG. 1). There was a problem in that the thickness of the heat spreading sheet became thicker with this structure. In addition, there is a problem in that the heat generated from the heating element is not directly transferred to the graphite but is transferred to the graphite through the PET film, resulting in a low heat dissipation rate.

Korean Patent Publication No. 10-2017-0109981 (October 10, 2017)

Accordingly, the technical problem of the present invention is conceived in this regard, and an object of the present invention is to provide a heat spreading sheet capable of improving the heat dissipation effect by directly dissipating heat generated from the heat generating element and dissipating heat from the heat generating element. Provides a manufacturing method.

In addition, there is provided a heat-diffusion sheet and a method of manufacturing the heat-diffusion sheet that can minimize the configuration of the heat-diffusion sheet to make the thickness of the heat-diffusion sheet slim.

According to one embodiment for realizing the object of the present invention described above, the film layer; An adhesive layer formed on one surface of the film layer and coated with an adhesive material; And a heat dissipation layer disposed adjacent to the heating element, formed on the other surface of the film layer, and radiating heat transferred from the heating element.

The heat dissipation layer may include a thermally conductive material and a thermal radioactive material.

The heat dissipation layer is formed by applying a heat dissipation composition, and the heat dissipation composition may include a filler, a binder, and a solvent including a thermally conductive material and a thermal radioactive material.

The heat dissipation composition may include 20 to 30% by weight of the filler, 5 to 50% by weight of a binder, and a residual solvent.

At this time, the filler may be made of 10 to 90% by weight of thermally conductive material and 10 to 90% by weight of thermally radioactive material.

In this case, the thermally conductive material may include one or more materials selected from the group consisting of alumina, aluminum and copper.

In this case, the thermal radioactive material may be boron.

Meanwhile, according to another embodiment for realizing the object of the present invention, applying an adhesive material to one surface of the film; And applying a heat dissipation composition comprising a filler, a binder, and a solvent containing a thermally conductive material and a thermally radioactive material to the other surface of the film.

In this case, the thermally conductive material is at least one material selected from the group consisting of alumina, aluminum and copper, and the thermally radioactive material may be boron.

After the step of applying the heat dissipation composition, the method may further include drying the film coated with the heat dissipation composition under a temperature of 150 to 200 ° C. for 15 to 20 minutes.

According to embodiments of the present invention, the present invention can improve the heat dissipation effect by directly dissipating the heat generated from the heat generating element by the main heat dissipation configuration of the heat diffusion sheet.

In addition, the configuration of the heat diffusion sheet can be minimized to make the thickness of the heat diffusion sheet slim.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a schematic view of a heat diffusion sheet according to the prior art.
2 is a schematic view for explaining a heat diffusion sheet according to an embodiment of the present invention.
3 is a block diagram illustrating a method of manufacturing a heat diffusion sheet according to another embodiment of the present invention.
4 and 5 are reference views for comparing the heat diffusion sheet according to an embodiment of the present invention with a heat diffusion sheet according to the prior art.

The present invention can be applied to various changes and can have various forms, and the embodiments are described in detail in the text. However, this is not intended to limit the present invention to a specific disclosure form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals are used for similar components. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms.

The terms are used only for the purpose of distinguishing one component from other components. The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, terms such as “comprises” or “consisting of” are intended to indicate the presence of features, numbers, steps, operations, components, parts or combinations thereof described in the specification, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, actions, components, parts or combinations thereof are not excluded in advance.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. Terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present application. Does not.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

2 is a schematic view for explaining a heat diffusion sheet according to an embodiment of the present invention. Referring to FIG. 2, the heat diffusion sheet according to an embodiment of the present invention includes a film layer 100 and an adhesive layer 200. , The heat dissipation layer 300 may be included.

The film layer 100 is a thin thin film and supports the adhesive layer 200 and the heat dissipation layer 300, which will be described later. At this time, the film layer 100 may be a PI (Polyimide) film having strong chemical resistance, abrasion resistance, and heat resistance.

The adhesive layer 200 is formed on one surface of the film layer 100 and is formed by applying an adhesive material. At this time, one surface of the film layer 100 may mean a lower surface of the film layer 100 in the drawing. The heat spreading sheet may be adhered to other external parts by the adhesive layer 200 formed on one surface of the film layer 100, and the external external parts may be magnetic sheets (not shown). The magnetic sheet (not shown) is a plurality of nano-ribbon layers stacked to block electromagnetic waves transmitted from the outside. When the heat diffusion sheet is adhered to the magnetic sheet through the adhesive layer 200, there is an effect that can block not only heat dissipation, but also electromagnetic fields transmitted from the outside.

The heat dissipation layer 300 is disposed adjacent to the heating element 700, is formed on the other surface of the film layer 100, and dissipates heat transferred from the heating element 700. At this time, the other surface of the film layer 100 may mean the upper side of the film layer 100 in the drawing.

The heat dissipation layer 300 is used to dissipate heat transferred from the external heat generating element 700 to prevent overheating of the heat generating element 700 or to prevent heat generated from being transmitted to other electronic components. ) May include a thermally conductive material and a thermally radioactive material.

In this case, the thermally conductive material may include one or more materials selected from the group consisting of alumina, aluminum, and copper (Cu). Further, the thermal radioactive material may be boron (B).

While alumina, aluminum, and copper are materials having high thermal conductivity, boron has heat radiation properties, but thermal conductivity has very low properties, so heat is formed by combining heat conductive materials such as alumina and boron to form a heat dissipation layer 300 It is to improve the thermal diffusivity by allowing the layer 300 to have thermal conductivity and thermal radiation.

At this time, the heat dissipation layer 300 may be formed by applying a heat dissipation composition, and the heat dissipation composition may include a filler, a binder, and a solvent including a thermally conductive material and a thermal radioactive material. Specifically, the heat dissipation layer 300 may be formed by applying and drying the heat dissipation composition on the other surface of the film layer 100.

In this case, the thermally conductive material constituting the filler may be at least one material selected from the group consisting of alumina, aluminum and copper, and the thermally radioactive material may be boron. Further, the solvent may be methanol or ethanol, and the binder may be an epoxy resin, acrylic resin, hydrocarbon resin, polyester resin, vinyl resin, or urethane resin, which is well dissolved in methanol and ethanol and has good adhesion and bonding strength. have.

At this time, the heat dissipation composition may include 20 to 30% by weight of the filler, 5 to 50% by weight of the binder, and the remainder of the solvent.

In addition, the filler may be made of 10 to 90% by weight of the conductive material and 10 to 90% by weight of the thermal radioactive material. This means that 20 to 30% by weight of the filler is assumed to be 100%, of which 10 to 90% by weight of the conductive material and the balance is composed of a radioactive material.

According to the present embodiment, since the heat dissipation layer 300 is formed by applying the ink-type heat dissipation composition to the film layer 100, there is a fear that the filler is bonded to the film layer 100 to crack the filler or cause powder blowing. This eliminates the need for a protective film such as a PET film. Therefore, the heat dissipation layer 300 may be disposed immediately adjacent to the heating element 700.

4 is a reference diagram for comparing and explaining a heat diffusion sheet according to an embodiment of the present invention and a heat diffusion sheet according to the prior art.

Referring to FIG. 4, the conventional heat diffusion sheet is to be transferred from the heating element 700 because the protective film (PET FILM) must be adhered to the upper surface of the graphite through the adhesive material (ADHENSIVE) to prevent this due to graphite cracking or powder flying. As the transferred heat is transferred in the order of PET film => adhesive material => graphite => adhesive material, the heat radiation value decreases (a in FIG. 4). On the other hand, according to the present embodiment, since the protective film for protecting the filler is not required, the heat dissipation layer 300 including the thermally conductive material and the thermal radioactive material can directly receive heat, and thus, from the heating element 700 As the transferred heat is transferred in the order of heat dissipation layer 300 => film layer 100 => adhesive, it is advantageous for heat diffusion compared to the prior art. In addition, the heat-diffusion sheet according to this embodiment does not require a protective film as compared to the heat-diffusion sheet according to the prior art, so that the thickness of the heat-diffusion sheet can be relatively reduced.

Specifically, the heat radiation values of the heat diffusion sheet according to the prior art and the heat diffusion sheet according to the present invention are compared with reference to FIG. 5 as follows.

In the present embodiment, when the heat dissipation composition is 26 wt% of the filler, and the binder and the solvent are 74 wt% of the remainder, the heat dissipation composition is applied to the film layer 100, and the film on which the heat dissipation composition is applied is 150-200 ° C. This is the case where the heat dissipation layer 300 is formed by drying for 15-20 minutes. At this time, the filler was a mixture of boron and alumina.

In this embodiment, the heat radiation value is represented by 0 to 1.0, and the closer the heat radiation value is to 0, the worse the radiation effect is, and the closer it is to 1, the higher the radiation effect.

Referring to (a) of FIG. 5, the heat radiation values of the heat diffusion sheet according to the prior art are PET film 0.72 to 0.76, adhesive material 0.72, graphite 0.72, and adhesive material 0.72.

On the other hand, referring to (b) of FIG. 5, the heat radiation values of the thermal expansion sheet according to the present embodiment are 0.82 to 0.86 of the heat dissipation layer 300, 0.72 to 0.76 of the film layer 100, and 0.72 of the adhesive material. Therefore, it was found that the heat dissipation value of the heat diffusion sheet according to the present embodiment is very high compared to the heat diffusion sheet according to the prior art. As described above, the heat diffusion sheet according to the present embodiment has the number of components constituting the heat diffusion sheet compared to the heat diffusion sheet according to the prior art (heat diffusion sheet of the present invention: 3, heat diffusion sheet according to the prior art: 4 As well as less), since the heat radiation layer 300, which is a radiation material, can directly receive heat generated from the heat radiation body 700, the radiation effect is excellent.

On the other hand, the heat dissipation layer 300 of the heat diffusion sheet according to the present embodiment appears to have a higher thermal radiation value than the graphite of the heat diffusion sheet according to the prior art, which means that the heat dissipation layer 300 according to the present embodiment is thermally conductive. It is due to the inclusion of materials and thermal radioactive materials.

On the other hand, according to another embodiment of the present invention, the step of applying an adhesive material to the film (S200), the step of applying the heat dissipation composition (S300) and drying the film (S400), the method of manufacturing a heat diffusion sheet Gives

Referring to Figure 3, the method for manufacturing a heat diffusion sheet according to this embodiment, the step of preparing a film (S100); Applying an adhesive material to one surface of the film (S200); It may include the step (S300) of applying a heat dissipation composition comprising a filler, a binder and a solvent containing a thermally conductive material and a thermal radioactive material on the other surface of the film.

At this time, the film may be a PI (Polyimide) film having strong chemical resistance, abrasion resistance, and heat resistance. In addition, the thermally conductive material constituting the filler may include one or more materials selected from the group consisting of alumina, aluminum and copper (Cu), and the thermally radioactive material may be boron (B).

In the present embodiment, the adhesive material is applied to one side of the film, and then the heat dissipation composition is applied to the other side, but is not limited thereto. It is also possible to apply the adhesive material to one side after applying the heat dissipation composition to the other side of the film.

Meanwhile, after the step of applying the heat dissipation composition (S300), the step of drying the film (S400) may be further included. Specifically, the film coated with the heat dissipation composition may be dried under a temperature of 150 to 200 ° C. for 15 to 20 minutes. When the heat dissipation composition is dried, a filler containing a thermally conductive material and a thermally radioactive material is bonded to the film, so that there is no fear of cracking of the filler or powder blowing, and a protective film such as a PET film is not required. Therefore, in the heat diffusion sheet manufactured according to the present embodiment, the heat dissipation layer 300 including the filler can be disposed directly adjacent to the heating element 700, so that the heat radiation value is higher than that of the heat diffusion sheet according to the prior art. appear.

Specifically, the heat radiation values of the heat diffusion sheet according to the prior art and the heat diffusion sheet according to the present embodiment are compared with reference to FIG. 5 as follows.

In this embodiment, the heat dissipation composition is 26 wt% of the filler, and the binder and the solvent are 74 wt% of the remainder. The heat dissipation composition is applied to the film layer (film), and the film on which the heat dissipation composition is applied is 150 to 200 ° C. This is the case where the heat dissipation layer 300 is formed by drying for 15-20 minutes. At this time, the filler was a mixture of boron and alumina.

In this embodiment, the heat radiation value is represented by 0 to 1.0, and the closer the heat radiation value is to 0, the worse the heat dissipation effect, and the closer it is to 1, the higher the heat radiation effect.

Referring to (a) of FIG. 5, the heat radiation values of the heat diffusion sheet according to the prior art are PET films 0.72 to 0.76, adhesive materials 0.72, graphite 0.72, and adhesive materials 0.72, and consequently, the heat radiation values are 0.2687 to 0.2837. Appears as

On the other hand, referring to (b) of FIG. 5, the heat radiation values of the heat diffusion sheet according to the method of manufacturing the heat diffusion sheet in this embodiment are heat dissipation layer 300 0.82 ~ 0.86, film layer 100 0.72 ~ 0.76, adhesive material As 0.72, as a result, the heat radiation value is 0.4251 to 0.4706. Therefore, it was found that the heat radiation value of the heat diffusion sheet according to the method of manufacturing the heat diffusion sheet of this embodiment is very high compared to the heat diffusion sheet according to the prior art.

In addition, the heat-diffusion sheet according to this embodiment does not require a protective film as compared to the heat-diffusion sheet according to the prior art, so that the thickness of the heat-diffusion sheet can be relatively reduced.

As described above, according to the present invention, the heat dissipation effect of the heat dissipation layer 300 including the heat-conducting material and the heat-radiating material can be directly received and dissipated to dissipate heat to improve the heat dissipation effect. In addition, since the protective film for protecting the heat dissipation layer 300 is not required, the thickness of the heat diffusion sheet can be made slim.

Although described above with reference to the embodiments, skilled artisans skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. You will understand that there is.

100: film layer
200: adhesive layer
300: heat dissipation layer
700: heating element

Claims (10)

Film layer;
An adhesive layer formed on one surface of the film layer and coated with an adhesive material; And
It is disposed adjacent to the heating element, is formed on the other surface of the film layer, and includes a heat dissipation layer for dissipating heat transferred from the heating element,
The heat dissipation layer,
It is formed by drying the film layer on which the heat dissipation composition is applied under a temperature of 150 to 200 ° C. for 15 to 20 minutes,
The heat dissipation composition includes a filler, a binder, and a solvent containing a thermally conductive material and a thermal radioactive material,
The heat dissipation composition,
The filler 20 to 30% content, the binder 5 to 50% content and the balance of the solvent,
The filler,
It consists of 10 ~ 90% content of thermally conductive material and 10 ~ 90% content of thermal radioactive material,
The thermally conductive material,
It includes at least one material selected from the group consisting of alumina, aluminum and copper,
The thermal radioactive material,
A heat diffusion sheet, characterized in that it is boron.
delete delete delete delete delete delete Applying an adhesive material to one side of the film; And
On the other side of the film, the step of applying a heat dissipation composition comprising a filler, a binder and a solvent comprising a thermally conductive material and a thermally radioactive material,
The heat dissipation composition includes a filler, a binder, and a solvent containing a thermally conductive material and a thermal radioactive material,
The heat dissipation composition,
The filler 20 to 30% content, the binder 5 to 50% content and the balance of the solvent,
The filler,
It consists of 10 ~ 90% content of thermally conductive material and 10 ~ 90% content of thermal radioactive material,
After the step of applying the heat dissipation composition,
Further comprising the step of drying the film coated with the heat dissipation composition for 15-20 minutes at a temperature of 150 ~ 200 ℃,
The thermally conductive material,
One or more materials selected from the group consisting of alumina, aluminum and copper,
The thermal radioactive material,
Boron, characterized in that the heat diffusion sheet production method.
delete delete

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