KR20080017707A - A heat solution sheet and a electronic device included the sheet - Google Patents

Abstract

A heat diffusion sheet and an electronic device adopting the same are provided to increase reliability of the sheet by removing air gap generation probability due to film laminating. A heat diffusion sheet includes a graphite sheet and at least one filler(14) combined or inserted into an edge formed on the graphite sheet. A film laminates at least one plane of the graphite sheet combined or inserted with the filler or laminates only the filler-combined or inserted part of the graphite sheet. An adhesive or a hetero film is further attached to the heat diffusion sheet.

Description

Heat diffusion sheet and electronic device employing the diffusion sheet {A HEAT SOLUTION SHEET AND A ELECTRONIC DEVICE INCLUDED THE SHEET}

1 is a partial cross-sectional view of a heat diffusion sheet produced by a laminating method using a film.

Figure 2 is an exemplary plan view of a heat diffusion sheet according to an embodiment of the present invention.

Figure 3 is a view for explaining a heat diffusion sheet manufacturing method according to an embodiment of the present invention.

4 is a view for explaining a method of manufacturing a heat diffusion sheet according to another embodiment of the present invention.

5 and 6 also illustrate a method of manufacturing a heat diffusion sheet according to another embodiment of the present invention, respectively.

The present invention relates to a heat diffusion sheet, and more particularly, to a heat diffusion sheet having a filler and an electronic apparatus employing the diffusion sheet.

The industry is designing parts, modules, and sets in consideration of high efficiency, high integration, high performance, and light and small size. When designers in each field design to satisfy the above-mentioned technical trends, more heat is generated than heat generated in the conventional design technology. In particular, the heat generated from various panels in the flat panel display area and the BLU (Back Light Unit) of the LCD greatly affects the picture quality. Especially, as the HD resolution and the size of the screen increase, More prominently, the industry is taking this seriously. As a result, the industry continues to research to efficiently deal with thermal problems (ie heat dissipation, heat diffusion, heat dissipation, heat collection, heat transfer, etc.).

As a means to solve the thermal problem, metals such as silver, copper, aluminum, gold, tungsten, iron, platinum, and ceramic-based thermal solution materials such as alumina oxide, magnesium zirconia magnesium oxide and boron nitride have excellent thermal conductivity. Has been used. Graphite materials have higher thermal conductivity (surface direction: 80-450W / mk, thickness direction: 3-7W / mk) and lower price and flexible physical properties than the heat dissipating materials made of metal or ceramics. In recent years, it has gained great attention not only in the electronics industry but also in industries requiring thermal solutions.

However, the biggest disadvantage of the graphite (Graphite) is that the chip (Chip: graphite powder) occurs during the production process because of the characteristics composed of the peeled particles. If these chips are scattered in electronic circuits, they cause short-circuits and cause great damage.

  As a surface treatment method for solving such a problem, a method using a coating liquid, a laminating method using a film, and the like are widely known.

Hereinafter, a problem of the above methods will be described by taking a heat dissipating or heat diffusing graphite sheet applied to a BLU bottom chassis of an LCD as an example.

First of all, the BLU's crack chassis can have irregularities, not flatness, in order to attach and fix various parts. The graphite sheet attached to the burch chassis must also be shaped to correspond to the irregularities formed in the burch chassis. In this case, it is necessary to process the edges of the holes formed so that the protrusions of the irregularities formed in the burch chassis can pass.

The method of treating the edges of the holes formed in the graphite sheet using the coating liquid will be described in detail.

First, a method of using a coating liquid is a method of coating a plane (upper and lower surface) and side edges of the graphite sheet by coating the coating liquid on a roller. This coating method has the advantage that the process sequence is monotonous, but it is not possible to expect a complete chip removal effect because it can not expect a uniform coating effect in the edge coating of the holes formed inside the graphite sheet.

On the other hand, the laminating method using a film can provide a good coating effect on the surface and hole edges, which can effectively solve the problem caused by chip scattering, but a separate heat press for edge sealing of the hole or sheet itself. Because of the need for a process, you must bear the loss of adding production facilities and adding production processes. Furthermore, in the laminating method using a film, the film located at the upper and lower portions of the graphite sheet is pressed and sealed by a hot press process, but the graphite sheet itself is shown in FIG. 1 between the upper and lower films F by the thickness of the graphite sheet itself. An air gap AG may be formed. The air gap AG causes the phenomenon of lifting of the sealed upper and lower films, and consequently acts as a factor of lowering product reliability.

On the other hand, in order to attach a thermal solution material such as graphite sheet to the BLU's crack chassis, an adhesive must be applied to one or both sides of the thermal solution material.At the convenience of the process, adhesive and release paper or release film are attached to the graphite sheet. Thomson may be cut in the condition. In this case, when the user peels the release paper or the release film from the graphite sheet, a problem may occur in that the release paper is torn due to the hole of the other perforated shape.

Accordingly, the present invention was devised to solve the above-mentioned problems, and an object of the present invention is to remove the possibility of graphite particles being scattered, while eliminating the possibility of air gap caused by film lamination, thereby increasing the reliability of the sheet itself. The present invention provides a heat spreading sheet and an electronic device employing the sheet.

Furthermore, another object of the present invention is to provide a heat diffusion sheet and an electronic device employing the sheet, which can secure the reliability of a product while significantly reducing the amount of film to be laminated, but laminating the graphite sheet.

In addition, another object of the present invention to provide a heat diffusion sheet and an electronic device employing the sheet that can be manufactured without a heat press process,

It is another object of the present invention to provide a heat diffusion sheet capable of lowering manufacturing cost and increasing production yield.

Furthermore, another object of the present invention is to provide a heat diffusion sheet capable of rapidly absorbing and diffusing heat from a heat source by improving thermal conductivity in the thickness direction as well as the surface direction of the sheet, and an electronic device employing the sheet.

Heat diffusion sheet according to an embodiment of the present invention for achieving the above object,

Graphite sheet;

At least one filler coupled to or inserted into an edge formed on the graphite sheet;

It characterized in that it comprises a; film laminating the at least one surface of the graphite sheet bonded or inserted filler or only the portion bonded or inserted filler.

According to this feature, a separate thermal process for sealing the edge portion is required by inserting a filler into the edge of the hole formed in the graphite sheet and the outer edge of the sheet. Of course, by eliminating the probability of occurrence of the air gap due to the hot press process, it is possible to speed up the production process and increase the reliability of the product.

Furthermore, at least one of the holes formed in the graphite sheet, which is the heat diffusion sheet of the present invention, is coupled to a part of the filler to be inserted and is shaped to serve as a locking step. This is to prevent the filler inserted graphite sheet is separated from the outer edge of the sheet when inserted into the roller for the film laminating.

Furthermore, in addition to the general anisotropic graphite sheet, the graphite sheet which is the heat diffusion sheet of the present invention may use a semi-anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20. This is to improve the thickness thermal conductivity of the sheet, so as to be able to quickly absorb the heat of the heat source to diffuse in the plane direction.

Furthermore, the electronic device according to the embodiment of the present invention,

A heat source;

Heat is absorbed and diffused from the heat source, wherein one or more fillers are bonded or inserted into an edge formed on the graphite sheet so that only one or more sides of the film are laminated or only one portion of the fillers is inserted or inserted into the film or more. It is characterized in that it comprises a diffusion sheet.

The electronic device of the present invention also has the same characteristics as those of the heat diffusion sheet described above.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of related known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

First, Figure 2 illustrates a planar structure of the heat diffusion sheet according to an embodiment of the present invention, as shown in the graphite sheet (Graphite Sheet: also known as GPS) is a component of the heat diffusion sheet (e.g., A plurality of holes 12 are formed to penetrate the structure formed in the burr chassis. The holes 12 are not necessarily formed in the graphite sheet 10, and may be selectively formed according to the demand of the consumer. Filler 14 for preventing chip scattering may be inserted into or coupled to the edge of the holes 12 and / or the outer edge of the graphite sheet GPS. The top and bottom surfaces of the graphite sheet (GPS: 12) inserted (or bonded) with the filler material 14 are laminated using a film, or one surface is laminated and the other surface is coated with a coating liquid. It can be processed to produce one heat diffusion sheet. In some cases, only the insertion or bonding portion of the filler may be laminated and the remaining portion may be coated.

Hereinafter, a description will be given of the structure of each heat diffusion sheet while explaining the manufacturing process of the above-described heat diffusion sheets by embodiment.

3 is a view for explaining a method for manufacturing a heat diffusion sheet according to an embodiment of the present invention, and more particularly, relates to a method for manufacturing a heat diffusion sheet when the heat diffusion sheet is laminated on both sides by a film. .

For reference, the thermal diffusion sheet manufactured by double-sided lamination,

The filler 14 having a material different from that of the graphite sheet 10 is bonded or inserted into at least one of the graphite sheet 10 and the edge of the hole 12 formed on the outer edge or the inner surface of the graphite sheet 10 to form a film. It characterized in that the double-sided laminating treatment at (16).

Referring to FIG. 3, first, at least one hole 12 is formed in the graphite sheet GPS: 10 using a method such as Thomson cutting (Step I) as necessary. As is already known, the graphite sheet (GPS: 10) is formed in a sheet state by rolling graphite with a strong force by foaming graphite in a flake structure. Such a graphite sheet (GPS: 10) is usually made to have a thermal anisotropy coefficient of 20 to 30, and has characteristics of a high anisotropic graphite sheet. For reference, the thermal properties of the high anisotropic graphite sheet have a high thermal conductivity in the plane direction of the graphite sheet but a low thermal conductivity in the thickness direction of the sheet as close as 20: 1 to 50: 1. For this reason, applying the high anisotropic graphite sheet to a large-area display device has limitations in effectively dissipating and removing heat generated from the center of the display. Therefore, by increasing the thermal conductivity of the heat source and the horizontal direction, a quasi-anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20 is used to rapidly absorb and diffuse heat generated from the heat source, thereby reducing the difference in heat diffusion between the display center and the outer portion. It is more preferable to use.

For reference, a method of manufacturing a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20 will be described by way of example. First, 30-150 mesh, preferably 30-100 mesh natural graphite, for example, high concentration of nitric acid and sulfuric acid Dilute the mixed solution (90% sulfuric acid and 10% nitric acid in volume ratio) with distilled water so that the normal concentration of sulfuric acid (first solution) is 0.3-1.5, low concentration intercalate solution, and advantageously natural graphite Intercalate by dispersing at a level of about 5-300 parts by weight of the intercalate solution per 100 parts by weight.

After draining and rinsing the excess solution from the intercalated natural graphite, the washed natural side edges are exposed to increased temperature (above 700 ° C-1000 ° C), and the intercalated graphite particles are in the original volume in the c-direction. It expands 20-80 times to form worm-shaped low-expansion graphite particles. Compression rolling molding the expanded graphite in this manner produces a semi-anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20.

On the other hand, the hole 12 formed in the graphite sheet (GPS: 10) is to penetrate the structure formed in the skin complex to which the heat diffusion sheet is attached to be formed in accordance with the number of structures. Furthermore, one or more of the holes formed in the graphite sheet GPS: 10 may be shaped to protrude to the inner side from the outer edge surface to form the locking step 22 as shown in FIG. 2. This is to prevent the graphite sheet (GPS: 10) in which the filler 14 described later is inserted from the sheet outer edge when inserted into the roller for film lamination.

As described above, when one or more holes are formed in the graphite sheet (GPS: 10) by Thomson cutting, only one side (lower surface) of the hole-formed graphite sheet (GPS: 10) is preferentially a resin-based film or a thin metal film. (Foils), an optical film, a lamination treatment (Step II) with any one of the film containing at least one powder having a thermal conductivity. For example, by laminating one side of the graphite sheet (GPS: 10) using a film, a problem that may occur when the graphite sheet 10 is handled, namely, damage to the graphite sheet 10, foreign matter adhesion, chip scattering, and body contamination Problems can be solved.

After the lamination is completed on one side, the filler 14 is inserted into the hole 12 formed in the graphite sheet (GPS: 10) and the outer edge of the sheet 10 by hand or jig (step III) (or joining). )do. At this time, the filler 14 is supported by a film laminated on the lower surface. The filler 14 is to prevent scattering of chips generated at the inner edge of the holes 12 and the outer edge of the graphite sheet GPS, and the material of the filler 14 is Any material may be used as long as it is not the same material as that of the graphite sheet 12 and can prevent chip generation of the graphite sheet 12. Preferably, the user or manufacturer may select and use various fillers according to the thickness of the graphite sheet or the shape of the holes formed on the inner surface. For example, metals, ceramics, plastics, sponges, papers, powders, rubbers, films, liquids, epoxys, resins, fibers such as cotton, wool, styrofoams, vinyls, and woods , Nylons, mixed materials containing one or more graphite particles or mixed materials containing one or more particles of the above-mentioned materials can be used in a variety of ways, and filling materials of different materials depending on the hole position Can be used. This allows for thermal equilibrium and, in some cases, differentiation of location-specific thermal solutions. If a solid filler such as metal or plastic is used as the filler 14, a separate component may be coupled to the filler 14 to facilitate coupling and assembly with other devices / components.

 A planar illustration of the graphite sheet (GPS: 10) with the filler material 14 inserted therein is shown in FIG. 3 (III). For reference, the height of the filler 14 and the graphite sheet to be inserted should be the same, but is not limited thereto. In addition, in the case where local heat is generated in the display device, in order to achieve thermal equilibrium, it may be desirable to form a hole at a location where local heat is generated and insert a filler having high thermal conductivity.

Meanwhile, when insertion (or bonding) of the filler 14 is completed, the remaining surface (upper surface) of the graphite sheet (GPS: 10) inserted after the filler 14 is replaced with a resin-based film, a thin metal film 16, and an optical fiber. The laminating process (step IV) is performed with any one of a film and a film containing at least one powder having thermal conductivity. FIG. 3 (IV) shows a cross section in the case where portion A shown in FIG. 3 (III) is subjected to double side laminating.

For reference, the optical films (reflective film, diffuser film, prism film, protective film, etc.) used as one of the films laminated on the graphite sheet (GPS: 10) are assumed to be applied to the BLU. This is to have the purpose of surface treatment of the sheet (GPS: 10) and the function of the optical film at the same time.

When the double-sided laminating treatment is completed for the graphite sheet (GPS: 10) in which the filler 14 is inserted, punching (punching) the film inside the hole formed in the double-sided laminating graphite sheet (GPS: 10) by a method such as cutting Thompson. ) Accordingly, the structure formed on the skin complex is in a state capable of penetrating into the hole 12 formed in the graphite sheet GPS: 10.

Thereafter, the adhesive solution 26 is applied onto one side film 16 of the graphite sheet (GPS: 10) which has been punched out, and the release paper 28 is attached onto the adhesive solution 26 (step V). At this time, the release paper 28 may be perforated to conform to the hole shape, and may not be perforated regardless of the hole shape. When the release paper 28 is perforated according to the hole shape, the release paper 28 may be torn due to the perforated hole shape when the release paper 28 is peeled off. Therefore, it is preferable to attach the release paper that is not perforated. will be. The adhesive solution 26 and the release paper 28 may be attached to both sides of the laminated film 16. For reference, the adhesive liquid 26 may be referred to as an adhesive because it is solidified. Of course, an adhesive such as a double-sided tape can also be used.

In this manner, a cross section of a portion (part A) of the graphite sheet 10 to which the adhesive liquid 26 and the release paper 28 are attached is shown in FIG. Referring to Fig. 3V, it can be seen that there is no air gap in the outer edge portion of the heat diffusion sheet according to the present invention.

That is, the heat diffusion sheet made by the above-described manufacturing method inserts the filler 14 into the inner edge of the hole 12 and the outer edge of the sheet 12 formed in the graphite sheet 10, thereby forming the inner edge of the hole 12 and the outer edge of the sheet. The surface treatment effect on the edge can be obtained. Furthermore, the present invention inserts the filler material 14 into the inner edge of the hole 12 formed in the graphite sheet 10 and the outer edge of the sheet, thereby preventing air gaps that may appear in the process of sealing the films located on both sides of the sheet. It will be able to prevent the occurrence at its source.

As a result, the heat diffusion sheet of the present invention has an advantage of having an excellent effect on surface treatment effect and product reliability as well as simplification of the manufacturing process equipment in comparison with a heat diffusion sheet manufactured by a general laminating method or a coating method. can do.

Furthermore, since the method attaches the release paper onto the adhesive after punching the film inside the hole formed in the sheet, the release paper may also be solved when the release paper is peeled from the sheet due to the perforated hole shape.

In the above embodiment, it is assumed that the adhesive sheet and the release sheet is a heat diffusion sheet attached, but may be assumed to be manufactured and sold as a heat diffusion sheet without the adhesive and the release paper attached.

Furthermore, the film 16 laminated on the graphite sheet 10 preferably includes metal or ceramic powder or graphite particles having at least excellent thermal conductivity in order to increase thermal conductivity.

Hereinafter, referring to FIG. 4, a method of manufacturing a heat diffusion sheet according to another embodiment of the present invention, and more specifically, only one surface thereof, will be described.

First, the heat diffusion sheet manufactured by laminating only one surface may include a graphite sheet 10, a filler 14 bonded or inserted into part or all of edges formed on the outer or inner surface of the graphite sheet 10, and One or more coating liquid layers 24 laminated on one side of the graphite sheet 10 bonded or inserted with the filler 14 and on the surface portion and the edge portion of the graphite sheet 10 not laminated. Characterized in that it comprises a.

Referring to FIG. 4, first, as shown in FIG. 3, one or more holes 12 are formed in the graphite sheet GPS: 10 using a Thomson cutting method (step I). As described above, the graphite sheet (GPS: 10) may be a high anisotropic graphite sheet having a thermal anisotropy coefficient of 20 to 30, and in some cases, a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20 may be used. . In addition, one or more of the holes formed in the graphite sheet (GPS: 10) is preferably formed to be combined with a part of the filler to be inserted to serve as the locking step 22. Of course, the graphite sheet of the present embodiment may also be a sheet without holes formed as in the previous embodiment.

As described above, when one or more holes are formed in the graphite sheet (GPS: 10) by Thomson cutting, one side (lower surface) of the hole-formed graphite sheet (GPS: 10) may be formed by a resin or thin film metal film or optical film. By laminating (Step II) the film containing one or more powders having thermal conductivity properties, the graphite sheet 10 may be damaged, foreign matter adhered, chip scattering, and body contamination.

After the one side laminating process is completed, the remaining surface (upper side, side) and the edge portion of the inside of the hole of the graphite sheet (GPS: 10), which are subsequently laminated, are subjected to roll coating 24 treatment with a resin-based coating solution ( Step III). The cross section of the graphite sheet (GPS: 10) coated with the coating is shown in FIG. 4 (III). By this coating treatment, not only one side of the graphite sheet (GPS: 10) but also the inner edge of the hole and the outer edge of the sheet are surface treated with the coating liquid layer. For reference, at least one coating liquid layer formed of the coating liquid may be formed. In addition, the coating liquids, resin-based films, adhesive liquids, and the like used may include a part of a metal powder having excellent thermal conductivity, or a ceramic powder, graphite particles, or the like.

On the other hand, when the coating treatment is completed on one side of the sheet 10, the film inside the hole formed in the coated graphite sheet (GPS: 10) is then punched out by a method such as cutting Thompson, and then the punched graphite sheet (GPS). The adhesive liquid 26 is applied onto the coating liquid layer 24 of: 10, and the release paper 28 is attached onto the adhesive liquid 26 (step IV). The adhesive solution 26 and the release paper 28 are also the same as those described with reference to FIG. 3, and a heat diffusion sheet to which the adhesive solution and the release paper is attached to the coating solution layer 24 and the film, respectively.

Thus, a partial cross section of the graphite sheet 10 to which the adhesive liquid 26 and the release paper 28 are attached is shown in FIG. 4 (IV). Referring to FIG. 4 (IV), it can be seen that the air diffusion sheet according to another embodiment of the present invention also does not have an air gap in the outer edge portion.

That is, the heat diffusion sheet made by the above-described manufacturing method coats the inner edge of the hole 12 formed in the graphite sheet 10 and the outer edge of the sheet with the coating liquid 24, so that only the lamination of one side of the sheet is used for the hole ( 12) The surface treatment effect on the inner edge and the outer edge of the sheet can be obtained. In addition, the present method has an advantage of increasing the heat diffusion effect than the case of using the film because the surface treatment effect is obtained by using the coating liquid instead of film laminating.

As a modified embodiment of the above-described manufacturing method, prior to the above-mentioned coating process of step III, a method of attaching a filler coated on one side to only the outer edge of the graphite sheet (GPS: 10) or only inside the hole You could do it. For example, the filler 12 is attached to only the outer edge of the sheet without inserting the filler into the hole 12 formed therein.

In some cases, the method of attaching the filler coated on one side to the graphite sheet (GPS: 10) may be additionally devised. In some cases, a method of attaching tapes or films coated with a pressure-sensitive adhesive to corner portions of coated surfaces of the graphite sheet 10 may be devised.

The reason why the filler is attached to the sheet edge and the outer edge of the sheet is that the edge of the sheet 10 may be damaged during the release of the release paper 28. To protect.

As a modification of the above-described embodiment, the filler may be combined or inserted into the outer edge and the outer edge portion of the graphite sheet 10.

As another modified embodiment, a heat diffusion sheet in which an adhesive is applied on the coating liquid layer 24 and a release paper or a release film is further attached may be considered.

Figure 5 also shows a view for explaining a method of manufacturing a heat diffusion sheet according to another embodiment of the present invention, more specifically, the lamination process only the part inserted filler.

Thus, the heat diffusion sheet laminating only the portion in which the filler is inserted,

On the graphite sheet, the filler is bonded or inserted into the edge (edge) formed on the graphite sheet, the film laminated only on the portion bonded or inserted into the filler, the surface portion and the edge portion of the non-laminated graphite sheet It characterized in that it comprises at least one coating liquid layer to be laminated.

Referring to FIG. 5, one or more holes 12 are formed (Step I) in the graphite sheet (GPS: 10) using a method such as Thomson cutting as shown in FIG. 3. As described above, the graphite sheet (GPS: 10) may be a high anisotropic graphite sheet having a thermal anisotropy coefficient of 20 to 30, and in some cases, a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20 may be used. . In some cases, a hole may not be formed in the sheet 10. In addition, one or more of the holes formed in the graphite sheet (GPS: 10) may be formed to be combined with a part of the filler to be inserted to serve as the locking step 22.

As described above, when one or more holes are formed in the graphite sheet (GPS: 10) by Thomson cutting, one side (lower surface) of the hole-formed graphite sheet (GPS: 10) is then formed into a resin series, a thin film metal film, an optical film, By laminating with any one of the films containing one or more powders having thermal conductivity (Step II), the graphite sheet 10 is damaged, foreign matter adhesion, chip scattering, body contamination, and the like.

After the lamination process is completed, the filler 14 is inserted into the outer edge of the graphite sheet (GPS: 10) after the lamination process (Step III). As such, the reason for inserting the filler 14 in the outer edge of the sheet 10 is to reduce the laminated film, and also to protect the edge portion of the sheet.

After the filling material 14 is inserted, only the periphery of the outer edge of the filling material 14 is laminated with any one of a resin-based film, an optical film, a thin film metal film, and a film including at least one powder having thermal conductivity. . Subsequently, one side of the non-laminated graphite sheet (GPS: 10) and an edge portion inside the hole are coated with a resin-based coating solution. By this coating treatment, all parts of the graphite sheet (GPS: 10) can be surface treated.

After the coating process is completed, the film inside the hole formed in the coated graphite sheet (GPS: 10) is then punched out by a method such as Thompson cutting, and then the coating liquid layer 24 of the punched graphite sheet (GPS: 10). The adhesive liquid 26 is apply | coated on the film 16 and the release paper 28 is affixed on the adhesive liquid 26 (step IV). In some cases, Thomson may cut the film inside the hole formed in the graphite sheet (GPS: 10) in a state where the release paper 28 is completely attached. 5 (V) and 5 (V) illustrate cross-sections in the case where Thompson cuts the film in the hole formed in the graphite sheet GPS: 10 in the state where the release paper 28 has been completely attached.

The heat diffusion sheet made by the above method is a method of mixing the film laminating method, the coating method and the filler insert, and the coating liquid, the filler, and the film can obtain the effect of surface treatment of all parts of the sheet 10. There is an advantage in that it can be manufactured inexpensively as compared to laminating both sides with a film.

In the above embodiment, the lamination of the entirety of one side is described as laminating only the portion where the filler is inserted with respect to the other side, but only the portion where the filler is inserted for both sides may be laminated.

Figure 6 also shows a view for explaining a method of manufacturing a thermal diffusion sheet in which only the portion of the filler inserted lamination process.

Referring to FIG. 6, first, as shown in FIG. 3, one or more holes 12 are formed in the graphite sheet GPS: 10 using a Thompson cutting method or the like (step I). In the present method, the graphite sheet (GPS: 10) may also be a high anisotropic graphite sheet having a thermal anisotropy coefficient of 20 to 30, and in some cases, a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20 may be used. In addition, one or more of the holes formed in the graphite sheet (GPS: 10) is preferably formed to be combined with a part of the filler to be inserted to serve as the locking step 22.

When one or more holes are formed in the graphite sheet (GPS: 10) by thomson cutting, one side (lower surface) of the hole-formed graphite sheet (GPS: 10) is then formed into a resin-based film, a thin metal film, an optical film, The lamination treatment (step II) with any one of the films containing at least one powder having thermal conductivity.

After the one side lamination process is completed, the filler 14 is inserted into the hole 12 of the graphite sheet (GPS: 10) after the lamination process (Step III). Thus, the reason for inserting the filler 14 only in the hole 12 is also to reduce the laminated film.

When the filling material 14 is inserted, the laminating the film around the hole 12 into which the filling material 14 is inserted (step IV). In this case, the periphery sheet cross section will be as shown in Fig. 6 (IV).

If the periphery of the hole 12 into which the filler 14 is inserted is laminated, then at least one coating liquid layer 24 is formed using a coating liquid on a portion (including the outer edge) of the unlaminated graphite sheet (GPS: 10) (step V). do. In this case, the cross-section is illustrated as (V) of FIG. 6.

After the coating process is completed, the film inside the hole formed in the coated graphite sheet (GPS: 10) is punched out by a method such as cutting Thompson, and then the coating layer 24 of the punched graphite sheet (GPS: 10) and The adhesive liquid 26 is apply | coated on the film 16, and the release paper 28 is affixed on this adhesive liquid 26 (step VI). In some cases, the film inside the hole formed in the graphite sheet (GPS: 10) may be thomson cut in a state where the release paper 28 is completely attached. The puncture state of such adhesive liquid and release paper is the same as that described in FIG.

The cross section of the heat diffusion sheet made by the above method is as shown in FIG. The heat diffusion sheet manufactured by the present method can also obtain the effect that all parts of the sheet 10 are surface-treated by the coating liquid layer, the filler, and the film, and can be manufactured at a lower cost than laminating the film with both sides. There is a profit.

Furthermore, as another embodiment, after laminating one side of the filler bonded or inserted graphite sheet, only the filler portion may be double-sided laminated to manufacture a heat diffusion sheet.

That is, a graphite sheet, a filler coupled or inserted into part or all of an edge formed on the graphite sheet, a first film obtained by laminating one side of the graphite sheet bonded or inserted with filler, and the filler coupled or A heat diffusion sheet may also be prepared including a second film having double-sided lamination only on the inserted portion, and at least one coating liquid layer laminated on the surface portion and the edge portion of the graphite sheet which has not been double-sided laminated.

In such a heat diffusion sheet, the material of each filler, the kind of film, the material of the coating liquid, the number of coating liquid layers, etc. are the same as the above-described embodiments.

Although not specifically mentioned in the above embodiments, the coating liquid and the films for laminating used to prepare the heat diffusion sheet of the present invention, PE, PP, PVC, Polyvinylidence chloride (PVDC), Polymethymethacrylate (PMMA), Polyamide (Nylon 6, 66, 610, 612, 11,46), polyacryl resin, polyalylate, polycarbonate, polyester resin, epoxy resin, polyimide resin, polyuresthane resin, polystyrene, polystyrene, polyacetal resin, polyethylene terephthalate (PET) It may include all or part of the material, the material of the thin metal film (foils) is all or a series of Al, Cu, Ag, Au, Pt, Mg, Zn, Ni, Fe, Pb, Sb, W, etc. It may include some, and may include all or part of various optical films applied to the BLU of the LCD, that is, a reflective film, a diffusion film, a prism film, a protective film.

Adhesives that can be used include Polyphenol resin, Polyvinyl butyral, PVAC, PolyLatex, Melamine resin, Urea resin, Resorcinol resin, a-olefin resin adhesives, CR-based adhesives, NBR, Isoprene rubber, a-cyanoacrylate adhesive, Silicon resin adhesive, It may include all or part of a series of Hot-Melt adhesives, Inorganic adhesives, and the like.

On the other hand, the heat diffusion sheet described in the above embodiments may include a PDP module, an LCD BLU, a portable communication device (mobile phone, PDA, PMP), a notebook computer, a digital camera, a video camera, an LED or an OLED, a FED, an automobile direction indicator, a brake light, and the like. The present invention can also be used as a thermal solution sheet for heat diffusion, heat dissipation, heat transfer, etc. of electronic or electric devices such as traffic signals, and also for edge treatment of graphite sheets applied to heat dissipation PCBs replacing metal metals. This usefully employable will be apparent to those skilled in the art, so a detailed description of the use will be omitted below.

As described above, the present invention inserts a filler into the inner edge of the hole formed in the graphite sheet and the outer edge of the sheet, thereby preventing an air gap that may appear in the process of sealing the films located on both sides of the sheet. Compared to the heat diffusion sheet manufactured by the general laminating method or the coating method, the heat diffusion sheet of the present invention has the advantage of having an excellent effect on the surface treatment effect and product reliability as well as simplifying the manufacturing process equipment. can do.

Furthermore, since the heat diffusion sheet of the present invention may obtain a surface treatment effect by using a coating solution instead of film laminating on one side, there is an advantage that the heat diffusion effect may be improved than a method of double-side lamination using a film.

In addition, by attaching a filler only to the outer edge of the graphite sheet, there is an advantage that can be prevented in advance damage to the sheet edge portion that may occur during the release paper release process.

Furthermore, since the present invention attaches the release paper onto the adhesive liquid after punching the film inside the hole formed in the graphite sheet, the effect of solving the problem that the release paper is torn due to the perforated hole shape when peeling the release paper from the sheet is also effective. Have

In addition, since the present invention can be manufactured using a semi-anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20, it also has an effect that can quickly absorb and disperse heat of the heat source compared to the general anisotropic graphite sheet.

On the other hand, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. For example, the material of the filler may be other than the material mentioned in the present embodiment. In addition, one or more coating liquid layers may be laminated on the film of the double-sided laminated graphite sheet, or the coating liquid layer may be laminated on one or both sides of the graphite sheet, and then double-sided lamination may be performed to manufacture the thermal diffusion sheet. . Furthermore, one side or both sides of the graphite sheet may be considered to be coated with a heat diffusion sheet laminated first, and then a heat diffusion sheet for laminating a coating liquid layer on both sides after lamination may be considered. Therefore, the true technical protection scope of the present invention should be defined only by the appended claims.

Claims (14)

Graphite sheet; At least one filler coupled to or inserted into an edge formed on the graphite sheet; And a film obtained by laminating the at least one side of the graphite sheet bonded or inserted into the filler or laminating only the portion of the filler bonded or inserted into the graphite sheet. The heat diffusion sheet according to claim 1, wherein an adhesive and a release paper or a release film are further attached to the heat diffusion sheet. The heat diffusion sheet according to claim 1 or 2, wherein at least one of the fillers has different materials. The method of claim 3, wherein the filler is a material different from the graphite sheet, metals, plastics, ceramics, sponges, papers, powders, rubbers, films, gel-type viscous materials, epoxy, resins, fibers , Styrofoam, vinyl, wood, nylon, mixed material containing at least one graphite particles, or a mixture material containing at least one particle of the above-mentioned materials, heat diffusion sheet, characterized in that . The heat diffusion sheet according to claim 3, wherein the graphite sheet is a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20. The film of claim 3, wherein one surface of the film laminated to the graphite sheet is a resin-based film, and the other surface is a thin metal film, an optical film, a film including at least one powder having thermal conductivity, and a resin-based film. Heat diffusion sheet characterized in that the film using any one of the film. The heat diffusion sheet according to claim 3, wherein the graphite sheet protrudes from the outer edge of the sheet toward the inner side to form a locking step. A heat source; It absorbs heat from the heat source and diffuses or dissipates or transfers, wherein one or more fillers are bonded or inserted into an edge formed on the graphite sheet so that one or more sides of the film lamination treatment or fillers are combined or inserted, and only one or more sides of the film are laminated. And a heat diffusion sheet being processed. The electronic device of claim 8, further comprising an adhesive liquid applied to the heat diffusion sheet. The electronic device of claim 8, wherein the at least one filler is bonded to or inserted into the heat diffusion sheet. The method of claim 8, wherein the filler is a material different from the graphite sheet, metals, plastics, ceramics, sponges, papers, powders, rubbers, films, gel type of viscous materials, epoxy, resins, fibers , Styrofoam, vinyls, trees, nylons, electronic materials, characterized in that any one of the mixed material containing at least one of the graphite particles or the mixed material containing at least one particle of the above-mentioned materials. The method according to claim 8, wherein one side of the film laminated on the heat diffusion sheet is a resin-based film, the other side is a thin metal film, optical film, a film containing at least one powder having thermal conductivity, resin series Electronic film, characterized in that the film using any one of the films of the film. The electronic device of claim 8, wherein the graphite sheet protrudes from the outer edge surface of the sheet to the inner side to form a locking step. The electronic device according to any one of claims 8 to 13, wherein the heat diffusion sheet is a quasi anisotropic graphite sheet having a thermal anisotropy coefficient of 3 to 20.

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