KR102237256B1 - LED module and LED lightening device including the same - Google Patents

Abstract

An LED module is provided. An LED module according to an exemplary embodiment of the present invention includes a light source unit including a plurality of LEDs mounted on one surface of a circuit board; A heat sink including a base substrate made of a metal material to support the light source unit and dissipate heat generated from the light source unit, and an insulating heat dissipation coating layer applied to an outer surface of the base substrate; A protective cover coupled to one surface of the heat sink to protect the light source unit from an external environment; And an internal space formed between the circuit board and the protective cover facing each other. At least one protrusion protruding from one surface of the protective cover and at least one protruding part for maintaining the internal pressure and the external pressure of the internal space in an equilibrium state by performing the role of a passage through which the air in the internal space can move to the outside. And an air vent means, wherein the at least one protrusion forms the inner space by maintaining a gap between one surface of the protective cover and the circuit board when the protective cover is coupled to the heat sink.

Description

LED module and LED lighting device including the same

The present invention relates to an LED module and an LED lighting device including the same, and more particularly, to an LED module and an LED lighting device capable of preventing an increase in internal pressure due to heat generated during operation of the LED.

LED is used in various lighting devices because it consumes little power, generates high brightness, and can be used semi-permanently.

For example, the LED is applied to a street lamp installed along a roadside for lighting of a street, safety of traffic, or aesthetics, or is installed in a tunnel and is used to secure a vehicle driver's view.

Such an LED lighting device has a structure in which a housing is made of metal such as aluminum, ceramic, plastic, etc., and an LED light source is disposed on one surface or inside of the housing, and then a translucent cover is coupled to the housing.

However, since the LED emits a lot of heat when it emits light, the air existing inside the light-transmitting cover is heated by heat, thereby increasing the exercise capacity and increasing the internal pressure.

This increase in the internal pressure acts as an external force to press the weakly engaging portion of the mechanically coupled portion.

Therefore, in order to improve the airtightness, the gasket that is normally disposed at the coupling portion cannot be restored to its original state even if the internal pressure is decreased due to repetitive stress caused by an increase in internal pressure, and the airtightness is weakened by maintaining the deformed state. have.

KR 10-2011-0097586 A

The present invention was conceived in consideration of the above points, and an LED module capable of improving the problem of an increase in internal pressure due to an increase in temperature by allowing the space formed between the light source unit and the protective cover to communicate with the outside, and an LED lighting including the same Its purpose is to provide a device.

In addition, another object of the present invention is to provide an LED module capable of improving heat dissipation while reducing overall weight by applying an insulating heat dissipation coating layer to a heat sink, and an LED lighting device including the same.

In order to solve the above problems, the present invention includes a light source unit including a plurality of LEDs mounted on one surface of a circuit board; A heat sink including a base substrate made of a metal material to support the light source unit and dissipate heat generated from the light source unit, and an insulating heat dissipation coating layer applied to an outer surface of the base substrate; A protective cover coupled to one surface of the heat sink to protect the light source unit from an external environment; And an internal space formed between the circuit board and the protective cover facing each other. At least one protrusion protruding from one surface of the protective cover and at least one protruding part for maintaining the internal pressure and the external pressure of the internal space in an equilibrium state by performing the role of a passage through which the air in the internal space can move to the outside. An air vent means; wherein the at least one protrusion comprises an LED for forming the inner space by maintaining a gap between one surface of the protective cover and the circuit board when the protective cover and the heat sink are coupled to each other. Modules are provided.

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In addition, the heat sink may include a plate-shaped radiating fin protruding from the base material in one direction, and the radiating fin may have at least one protrusion formed to increase a contact area with external air.

In addition, the protective cover includes a plurality of convex portions formed upwardly in regions corresponding to the plurality of LEDs, and the plurality of convex portions are accommodated to accommodate the LED on an opposite surface facing the LED. Each of the spaces is formed, and the receiving spaces respectively formed in the plurality of convex portions are the inner spaces so that the air heated by the light emission of the LED can flow along the inner space and then be discharged to the outside through the air vent means. They can communicate with each other through.

In addition, the air vent means may include a moving path formed through the heat sink to communicate with the inner space, and a vent member attached to one surface of the heat sink to cover an open upper portion of the moving path. In this case, the vent member may be made of a membrane material having breathability and moisture permeability.

In addition, the air vent means may be disposed so that at least a portion of the air vent means is located at a position not overlapping with the circuit board.

In addition, the insulating heat dissipation coating layer is a coating layer forming component comprising a main resin; And an insulating heat dissipating filler included in an amount of 25 to 70 parts by weight based on 100 parts by weight of the main resin.

In a preferred embodiment, the insulating heat dissipating filler may include silicon carbide, and the insulating heat dissipating filler may have an average particle diameter of 10 nm to 15 μm. In addition, the insulating heat dissipation filler may have a ratio of D50 and D97 of 1:4.5 or less (here, D50 and D97 mean particle diameters of the insulating heat dissipation filler when the cumulative degrees are 50% and 97%, respectively, in the volume cumulative particle size distribution. box)

According to the present invention, the space formed between the light source unit and the protective cover is communicated with the outside through the air vent means to maintain the airtightness and mechanical coupling force by maintaining the pressure between the inner space and the outside in an equilibrium state to secure durability and product reliability. can do.

In addition, according to the present invention, by applying an insulating heat dissipating coating layer to the heat sink, the overall weight is reduced and heat dissipation is improved, thereby preventing a decrease in light efficiency due to deterioration and extending the life of the product.

1 is a view showing an LED module according to an embodiment of the present invention,
Figure 2 is a bottom perspective view of Figure 1,
Figure 3 is an exploded view of Figure 1,
Figure 4 is a view as seen from the bottom of Figure 3,
5 is a partially cutaway view of the protective cover and heat sink in FIG. 1;
6 is an exploded view showing an LED module according to another embodiment of the present invention;
FIG. 7 is a partially cutaway view of the protective cover and the heat sink in the state in which FIG. 6 is combined;
8 is a view showing a cable fastener applied to FIG. 6, (a) is a perspective view, (b) is a partially cutaway view,
9 is a view showing an LED module according to another embodiment of the present invention,
Figure 10 is an exploded view of Figure 9, and,
11 is a partial cutaway view of the protective cover in FIG. 9.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and the same reference numerals are added to the same or similar components throughout the specification.

The LED modules 100, 200, and 300 according to an embodiment of the present invention include a light source unit 110, a heat sink 120, and a protective cover 130, as shown in FIGS. 1 to 11.

The light source unit 110 generates light when power is applied, and at least one light source may be mounted on a plate-shaped circuit board 112 having a predetermined area.

Here, the light source may be a known LED 111, and a plurality of the light sources may be arranged in a predetermined pattern. In addition, the circuit board 112 may be a printed circuit board having a circuit pattern formed on at least one surface thereof, and the printed circuit board may be a flexible circuit board or a rigid circuit board. Preferably, the circuit board 112 may be a metal PCB so that heat generated when the LED 111 generates heat can be smoothly transferred to the heat sink 120 side.

The light source unit 110 may be electrically connected to power supplied from the outside by including a connector 113 electrically connected to the circuit pattern on the side of the circuit board 112. Here, the connector 113 may be electrically connected to an external power source through a cable C passing through a cable insertion hole 125 formed through the base substrate 121 side of the heat sink 120 to be described later. .

In addition, in the light source unit 110, one surface of the circuit board 112 may be attached to one surface of the heat sink 120 through an adhesive layer, or may be detachably fixed through a fastening member.

The heat sink 120 supports the light source unit 110 and discharges heat generated when the LED 111 is operated to the outside. To this end, the heat sink 120 may include a plate-shaped base material 121 having a predetermined area to support the light source unit 110.

That is, the base substrate 121 may be made of a material having excellent heat dissipation so that heat generated from the LED 111 can be effectively radiated while firmly supporting the light source unit 110. For example, the base substrate 121 may be a metal material such as aluminum or copper.

Accordingly, heat generated when the LED 111 emits light is transferred to the heat sink 120 and then released to the outside, thereby preventing a decrease in light efficiency due to deterioration and extending the product life of the LED.

At this time, the heat sink 120 may include at least one radiating fin 122 protruding from the base material 121 in one direction, and the radiating fin 122 may have a plate shape to increase a contact area with outside air. It can be implemented in the form of.

In addition, at least one protrusion 123 may be recessed on the surface of the radiating fin 122 so as to further increase the contact area with the outside air. For example, the protrusion 123 may be formed in a direction parallel to the width direction of the radiating fin 122. However, the shape of the protrusion 123 is not limited thereto, and any known method can be applied as long as the contact area with the outside air is increased, such as a grid pattern and a diagonal pattern.

In addition, the base substrate 121 is not limited thereto, and any material having heat dissipation may be used without limitation. As a part of this, the base substrate 121 may be made of only a known heat-dissipating plastic material, and may be in a form in which a metal material and heat-dissipating plastic are integrated through insert molding.

As a specific example, the base substrate 121 may be formed of a heat dissipating member-forming component including a graphite composite and a polymer resin, and a metal plate and the heat dissipating member-forming component may be integrated through insert injection molding.

Here, when the base material is configured in a form in which a metal plate and the heat dissipating member forming component are integrated through insert injection molding, the metal plate may be completely covered with the heat dissipating member forming component, and the light source unit 110 is disposed. It may be in a form in which one side that is exposed is exposed to the outside.

In addition, the graphite composite may be formed as a composite in which nanometal particles are bonded to the surface of plate-shaped graphite, and the nanometal particles may be a conductive metal to exhibit an electromagnetic wave shielding effect, and the graphite composite may be the nanometal. A catecholamine layer may be included on the particles. Moreover, when a catecholamine layer, for example a polydopamine layer, is formed on the nanometal particles constituting the graphite composite, the graphite composite may be included in an amount of 50 to 80% by weight based on the total weight of the heat dissipating member forming component constituting the heat sink. have.

Meanwhile, the heat sink 120 may include an insulating heat dissipation coating layer 126 for preventing electrical short while implementing more excellent heat dissipation. That is, the insulating heat dissipation coating layer 126 may be formed to surround the outer surface of the base material 121.

Accordingly, the LED module (100, 200, 300) according to the present invention can implement more excellent heat dissipation through the insulating heat dissipation coating layer 126, thereby reducing the number of radiating fins 122 protruding from the base substrate 121 or reducing the number of radiating fins ( Even if the area of 122) is narrowed, it is possible to secure heat dissipation at a level equal to or higher than the conventional one.

Through this, the LED module (100, 200, 300) according to the present invention can reduce the number of use of the radiating fins 122 included in the heat sink 120 or the formation area of the radiating fins 122, thereby reducing the overall weight and being equivalent to the conventional one. The heat dissipation performance above the level can be realized.

In addition, the heat sink 120 according to the present invention secures insulation through the insulating heat dissipation coating layer 126, so that even if the LED modules 100, 200, and 300 according to the present invention are applied outdoors, an electrical short circuit caused by an external environment such as rainwater in rainy weather. Stable operation may be possible by remarkably reducing the possibility of occurrence. In addition, even if the base substrate 121 constituting the heat sink 120 is made of a metal material having electrical conductivity, electrical stability and reliability can be secured.

A detailed description of the insulating heat dissipation coating layer 126 will be described later.

The protective cover 130 is for protecting the light source unit 110 disposed on one surface of the heat sink 120 from an external environment, and may be detachably coupled to one surface of the heat sink 120.

To this end, at least one fastening hole 124 and 133 may be formed through the heat sink 120 and the protective cover 130 at positions corresponding to each other so that the fastening member 170 can pass therethrough. Accordingly, the protective cover 130 may be fixed to the heat sink 120 through the fastening member 170.

Here, the fastening member 170 may be fixed in a screwing manner through a screw portion formed on the inner surfaces of the fastening holes 124 and 133, or may be fixed through a fixing member such as a separate nut member.

In addition, an airtight member 140 such as an O-ring may be disposed on a contact surface between the protective cover 130 and the heat sink 120 on the edge side of the protective cover 130. Through this, when the protective cover 130 and the heat sink 120 are coupled to each other through the fastening member 170, moisture can be prevented from flowing into the light source unit 110 through the coupled gap.

In this case, the protective cover 130 may include a convex portion 131 formed to be convex upward in a region corresponding to the LED 111, and the convex portion 131 faces the LED 111 An accommodation space 132 for accommodating the LED 111 may be formed on the opposite surface.

Through this, when the protective cover 130 is fastened to the heat sink 120, the LED 111 having a predetermined height may be accommodated by the receiving space 132, and the protective cover 130 The edge side may be in close contact with the heat sink 120 smoothly.

In addition, when a plurality of LEDs 111 are mounted on the circuit board 112, a plurality of convex portions 131 formed on the protective cover 130 may also be formed in a plurality to correspond to the LED 111.

In this case, the plurality of receiving spaces 132 for accommodating the LED 111 are mutually formed through an inner space S formed between one surface of the protective cover 130 and one surface of the heat sink 120 facing each other. Can be communicated.

To this end, at least one protrusion 134 for maintaining a distance from the circuit board 112 may be formed on one surface of the protective cover 130, more specifically, on one surface facing the heat sink 120. have. Accordingly, a predetermined internal space (S) is formed through the protrusion 134 between one surface of the protective cover 130 and one surface of the heat sink 120 facing each other, so that a plurality of accommodation spaces 132 Can be communicated.

For example, the protrusions 134 may be provided in a bar shape having a predetermined length as shown in FIG. 4, and a plurality of the protrusions 134 may be spaced apart at intervals. However, the shape of the protrusion 134 is not limited thereto, and may be provided in a dot shape, and if a shape capable of forming a predetermined gap between the circuit board 112 and the protective cover 130 facing each other It should be noted that both can be applied.

The air vent means (150, 250, 350) serves as a passage through which the air in the inner space (S) formed through the protrusion (134) can move to the outside, so that the pressure of the inner space (S) and the external pressure are brought into an equilibrium state. I can keep it.

That is, the air existing in the receiving space 132 may be heated by heat generated when the LED 111 emits light, and may flow along the inner space S in which the plurality of receiving spaces 132 communicate. have. Accordingly, when a predetermined time elapses after the air heated by the heat generated when the LED 111 emits light flows through the inner space (S), it enters the plurality of accommodation spaces 132 and the inner space (S). The temperature of the existing air can all be changed to an elevated state.

For this reason, the air existing in the receiving space 132 and the inner space S tends to decrease the pressure by increasing the volume in order to maintain an equilibrium state. Accordingly, when the receiving space 132 and the inner space S communicated with each other are completely sealed, the internal pressure may increase due to the increase in temperature, and the increased internal pressure is an external force that pushes the weak part of the mechanism coupling part. By acting as, it is possible to weaken the durability of the mechanism coupling portion.

In particular, in the case of the hermetic member 140 disposed between the protective cover 130 and the heat sink 120 for airtightness, the strength of the material is weak due to the characteristics of the material, and thus deformation due to the internal pressure may occur. Accordingly, the airtight member 140 may be repeatedly deformed depending on whether or not the light source unit 110 is operated, thereby losing a restoring force, and thus may not maintain initial airtightness.

In the present invention, the receiving space 132 according to the temperature change of the LED 111 by allowing the air existing in the receiving space 132 and the inner space (S) to be moved to the outside through the air vent means (150, 250, 350). ) And the internal pressure of the internal space (S) can be flexibly changed. For this reason, the internal pressure of the receiving space 132 and the internal space S can always maintain an equilibrium state with the external air pressure.

To this end, the air vent means (150, 250, 350) includes a moving path 151 formed through to communicate with the inner space (S), and a vent member 152 covering the open upper portion of the moving path 151. I can.

In this case, the vent member 152 may be made of a membrane material having breathability and moisture permeability. Accordingly, the LED module (100, 200, 300) according to the present invention can maintain a pressure equilibrium state with the outside air through free movement of the air flowing in and out through the vent member 152, and the internal space (S) from the outside. Condensation can be improved by blocking the inflow of moisture to the side to prevent oxidation of electronic components due to penetration of moisture, while water vapor existing in the inner space S can be discharged to the outside.

As the vent member 152, a membrane material having breathability and moisture permeability has been exemplified, but the present invention is not limited thereto, and all known materials commonly used for discharging the air inside may be used.

Meanwhile, in the drawing, one air vent means 150, 250, 350 is provided to communicate with the inner space S, but the present invention is not limited thereto, and at least one or more air vent means 150, 250, and 350 may be installed with the inner space S, and the When the inner space S is formed of a plurality of spaces isolated from each other, the plurality of spaces isolated from each other may be installed in a number matching at least one-to-one. In addition, it should be noted that the installation positions and the number of installations of the air vent means 150, 250, and 350 can be appropriately changed according to design conditions.

As a specific example, in the air vent means 150, the moving path 151 is formed through the heat sink 120 as shown in FIGS. 1 to 5 to communicate with the inner space (S). , The vent member 152 may be attached to one surface of the heat sink 120 to cover the open upper portion of the moving path 151.

In this case, the vent member 152 may have a relatively larger area than the cross-sectional area of the moving path 151, and the moving path 151 is formed at a position where at least a portion does not overlap with the circuit board 112 Can be.

As another example, the air vent means 250 is formed through the movement path 151 along the height direction of the cable fixing unit 160 as shown in Figs. 6 to 8 to communicate with the inner space (S). The vent member 152 may be attached to one surface of the cable fixing member 160 so as to cover the open upper portion of the moving path 151.

Here, the cable fixing tool 160 may have a through hole 162 through which a cable (C) for electrically connecting an external power source to the connector 113 may be inserted, and the heat sink 120 By being inserted into the cable insertion hole 125 formed in the, it can simultaneously serve as a sealing member that prevents external moisture from flowing into the light source unit 110.

In this case, compared to the above-described embodiment, since a separate processing for changing the heat sink 120 itself or forming a moving path is unnecessary, reliability and productivity of the product can be improved.

As another example, the air vent means 350 may have the moving path 151 formed through the protective cover 130 to communicate with the inner space S as shown in FIGS. 9 to 11. In addition, the vent member 152 may be attached to the inner surface of the protective cover 130 so as to cover the open lower part of the moving path 151.

Meanwhile, the insulating heat dissipation coating layer 126 applied to the present invention may include a coating layer forming component including a main resin and an insulating heat dissipation filler, and the insulating heat dissipation filler is 25 to 70 parts by weight based on 100 parts by weight of the main resin. Can be included.

Specifically, the main resin is for forming a coating layer, and components known in the art may be used without limitation.

However, the main resin has improved heat dissipation performance due to improved adhesion to the base substrate 121, heat resistance not embrittled by heat, insulation not embrittled by electrical stimulation, mechanical strength, and insulating heat dissipation filler. Glycidyl ether type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, linear aliphatic type epoxy resin, rubber-modified epoxy resin and these It may include an epoxy resin containing at least one selected from the group consisting of derivatives of.

In addition, when considering the heat dissipation characteristics, durability improvement of the insulating heat dissipation coating layer, surface quality improvement of the insulating heat dissipation coating layer, and improvement of dispersibility of the heat dissipation filler, the main resin is compared with the insulating heat dissipation filler described later, especially silicon carbide. It may contain compounds with very good compatibility.

In addition, the type of the curing agent included in the coating layer forming component together with the epoxy resin that can be used as the above-described main resin may vary according to the specific type of epoxy that can be selected, and the specific type is a curing agent known in the art. It may be used, and preferably includes any one or more components of an aliphatic polyamine-based curing agent, an aromatic polyamine-based curing agent, an acid anhydride-based curing agent, and a catalyst-based curing agent.

Meanwhile, the coating layer forming component may include a first curing agent including an aliphatic polyamine-based curing agent as a curing agent and a second curing agent including at least one selected from the group consisting of an aromatic polyamine-based, acid anhydride-based curing agent, and a catalyst-based curing agent. I can.

This is very advantageous in improving compatibility with the insulating heat dissipating filler described later, especially silicon carbide, and is advantageous in all physical properties such as adhesion, durability, and surface quality of the insulating heat dissipating coating layer. There is an advantage of further preventing cracks from occurring or peeling in the insulating heat dissipating coating layer formed on the corresponding portion when curved or stepped, not a smooth plane, is formed. In addition, in order to express more improved physical properties, preferably, the curing agent may include the first curing agent and the second curing agent in a weight ratio of 1:0.5 to 1.5, preferably in a weight ratio of 1:0.6 to 1.4.

If the weight ratio of the first and second hardeners is less than 1:0.5, the adhesion strength with the base substrate 121 may be weakened, and if the weight ratio exceeds 1:1.4, the elasticity of the coating film may be lowered and durability. Because it can fall.

In addition, the coating layer forming component may include 25 to 100 parts by weight of the curing agent, preferably 40 to 80 parts by weight, based on 100 parts by weight of the main resin. This is, when the curing agent is provided in less than 25 parts by weight, the durability of the resin is uncured or the formed insulating heat dissipating coating layer may be deteriorated. This is because the coating layer can break.

Meanwhile, the insulating heat dissipating filler may be used without limitation as long as it has both insulation and heat dissipation properties in its material. In addition, the shape and size of the insulating heat dissipation filler are not limited, and the structure may be porous or non-porous, and may be selected differently depending on the purpose. For example, the insulating heat dissipation filler is silicon carbide, magnesium oxide, titanium dioxide, aluminum nitride, silicon nitride, boron nitride, aluminum oxide, silica, zinc oxide, barium titanate, strontium titanate, beryllium oxide, manganese oxide, zirconia and boron oxide. It may include one or more selected from the group consisting of. However, preferably, silicon carbide in terms of facilitating the achievement of desired properties such as excellent insulation and heat dissipation performance, ease of formation of an insulating heat dissipation coating layer, uniform insulation and heat dissipation performance after the formation of an insulating heat dissipation coating layer, and surface quality of the insulating heat dissipation coating layer. Can be

In addition, in the case of the insulating heat dissipating filler, a filler whose surface is modified with a functional group such as a silane group, an amino group, an amine group, a hydroxy group, or a carboxyl group may be used, and at this time, the functional group may be directly bonded to the surface of the filler, or It may be indirectly bonded to the filler via a substituted or unsubstituted aliphatic hydrocarbon having 1 to 20 carbon atoms or a substituted or unsubstituted aromatic hydrocarbon having 6 to 14 carbon atoms.

In addition, the insulating heat dissipation filler may be a core-shell type filler having a known conductive heat dissipation filler such as carbon-based or metal as a core, and an insulating component surrounding the core.

In this case, the insulating heat dissipation filler may have an average particle diameter of 10 nm to 15 μm, preferably 30 nm to 12 μm. If the average particle diameter is less than 10 nm, there is a risk of an increase in product unit cost, and the amount of insulating heat dissipating filler buried on the surface after being implemented as an insulating heat dissipating coating layer increases, resulting in a decrease in heat dissipation performance. This is because if it is exceeded, the uniformity of the surface may decrease. On the other hand, the insulating heat-dissipating filler provided to improve the dispersibility of the heat-dissipating heat-dissipating filler may have a ratio of D50 and D97 of 1:4.5 or less, preferably 1:1.2 to 3.5. This is because when the ratio of D50 and D97 exceeds 1:4.5, the uniformity of the surface decreases, the dispersibility of the heat dissipation filler is not good, so the heat dissipation effect may not appear uniformly, and the particle diameter contains relatively large particles. This is because the thermal conductivity may be relatively high, but the desired heat dissipation characteristic cannot be expressed. The D50 and D97 denote the particle diameters of the insulating heat dissipating filler when the cumulative degrees are 50% and 97%, respectively, in the volume cumulative particle size distribution. Specifically, in a graph (particle diameter distribution based on volume) in which the particle diameter on the horizontal axis and the volume accumulation frequency from the side with the smallest particle diameter on the vertical axis, the volume percent from the smallest particle diameter to the volume cumulative value (100%) of all particles. The particle diameters of the particles corresponding to the cumulative values of 50% and 97%, respectively, correspond to D50 and D97. The cumulative volume particle size distribution of the insulating heat dissipating filler can be measured using a laser diffraction scattering particle size distribution device.

On the other hand, the average particle diameter of the insulating heat dissipation filler can be used by changing the particle diameter according to the coating thickness of the insulating heat dissipation coating layer to be formed. For example, when forming an insulating heat dissipation coating layer having a thickness of 25 μm, heat dissipation of an average particle diameter of 1 to 7 μm A filler may be used, and in the case of forming an insulating heat dissipating coating layer having a thickness of 35 μm, a heat dissipating filler having an average particle diameter of 8 to 12 μm may be used. However, in order to further improve the dispersibility of the heat dissipating filler in the composition, it is preferable to use an insulating heat dissipating filler that satisfies both the average particle diameter range of the heat dissipating filler according to the present invention and the ratio range of D50 and D97.

In addition, the insulating heat dissipation coating composition may further include a property enhancing component. When the insulating heat dissipation coating layer 126 applied to the present invention is coated on the base substrate 121, such a property enhancing component may exhibit further improved insulation and heat dissipation and at the same time exhibit excellent adhesion, thereby improving durability. Such a property enhancing component may be a silane-based compound, and a known silane-based compound employed in the art may be used without limitation.

On the other hand, the above-described insulating heat dissipation coating composition may contain a colorant to minimize loss of color due to light, air, moisture, or extreme temperature, and a matting agent for removing light to realize the stability of the coating film surface. It may further include, and may further include a flame retardant for improving flame retardancy.

In addition, the above-described insulating heat-dissipating coating composition may include a dispersant and a solvent for improving the dispersibility of the insulating heat-dissipating filler and realizing a uniform insulating heat-radiating coating layer, and may include a UV stabilizer for preventing yellowing due to UV. In addition, it may contain an antioxidant for preventing discoloration of the coating dried coating film, preventing degradation of physical properties such as brittleness due to oxidation, adhesion strength, and the like. In addition, the insulating heat dissipation coating composition is a leveling agent, a pH adjuster, an ion trapping agent, a viscosity modifier, a thixotropic agent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a colorant, a dehydrating agent, a flame retardant, an antistatic agent. One or two or more kinds of various additives such as, anti-repellent, preservative, and the like may be added.

The present invention will be described in more detail through the following examples, but the following examples do not limit the scope of the present invention, which should be construed to aid understanding of the present invention.

<Example 1>

The insulating coating layer forming component is polyethylene polyamine as the first curing agent and 2,4,6-tris[N,N-dimethylamino]methyl]phenol as the first curing agent based on 100 parts by weight of the compound represented by the following formula (1) as the main resin. 60 parts by weight of a hardener containing a weight ratio of 1: 1, an average particle diameter of 5 μm, 47 parts by weight of silicon carbide with a ratio of D50 and D97 of 1:1.6, an epoxy-based silane compound, a physical property enhancing component (Shanghai Tech Polymer Technology , Tech-7130) 3 parts by weight, 44 parts by weight of talc as a colorant, 44 parts by weight of titanium dioxide as a matting agent, 22 parts by weight of a flame retardant trizinc bis (orthophosphate), 2-(2'-) as a UV stabilizer 0.5 parts by weight of hydroxy-3, 5'-di(1, 1-dimethylbenzyl-phenyl)-benzotriazole, 1 part by weight of 2-hydroxyphenylbenzothiazole as antioxidant, dispersant (isobutylaldehyde and urea) Condensate) 5 parts by weight, 13 parts by weight of 1-butanol, 13 parts by weight of n-butyl acetate, 13 parts by weight of 2-methoxy-1-methylethyl acetate, 9 parts by weight of methyl ethyl ketone, 37 parts by weight of ethyl acetate Parts, 9 parts by weight of toluene, 43 parts by weight of 4-methyl-2-pentanone, and 103 parts by weight of xylene were mixed and stirred, after stirring, air bubbles contained in the mixture were removed, and the final viscosity was 100 to 130 cps based on 25°C. To prepare an insulating heat dissipation coating composition as shown in Table 1 below, and then stored at 5°C.

[Formula 1]

Each of R ¹ to R ⁴ is a methyl group, and n is a rational number such that the weight average molecular weight of the compound represented by Formula 1 is 2000.

<Examples 2 to 13>

It was prepared in the same manner as in Example 1, but as shown in Tables 1 and 2 below, an insulating heat-dissipating coating composition was prepared by changing the average particle diameter, particle size distribution, and weight ratio of the curing agent.

<Comparative Examples 1 to 3>

It was prepared in the same manner as in Example 1, but an insulating heat dissipating coating composition was prepared by changing the content of the insulating heat dissipating filler as shown in Table 3 below.

<Experimental Example 1>

The heat dissipation coating composition prepared in Examples and Comparative Examples was spray-coated so that the final thickness was 25 µm on the entire surface of an aluminum material (Al 1050) having a thickness of 1.5 mm and a width x length of 35 mm x 34 mm, respectively. After heat treatment at 150° C. for 10 minutes to prepare a heat dissipating unit with an insulating heat dissipating coating layer formed, the following physical properties were evaluated and shown in Tables 1 to 3.

1. Thermal conductivity evaluation

After placing the heat dissipation unit in the center of the acrylic chamber 32 cm x 30 cm x 30 cm in width, length and height respectively, the temperature inside the chamber and the temperature of the heat dissipation unit were adjusted to be 25±0.2°C. Thereafter, a test specimen was prepared by attaching an LED of 20 mm x 20 mm horizontally and vertically to the heat dissipation unit as a heat source using a TIM (thermal conductive tape: 1W/mk). Heat was generated by applying an input power of 2.1W (DC 3.9V, 0.53A) to the heat source of the prepared specimen, and after holding for 90 minutes, the temperature of the heat dissipation unit was measured to evaluate the thermal conductivity. Specifically, the thermal conductivity was calculated according to Equation 1 below based on the temperature measured under the same conditions for a substrate not provided with a heat dissipation coating layer.

[Equation 1]

2. Heat radiation evaluation

After placing the heat dissipation unit in the center of the acrylic chamber 32 cm x 30 cm x 30 cm in width, length and height respectively, the temperature inside the chamber and the temperature of the heat dissipation unit were adjusted to be 25±0.2°C. Thereafter, a test specimen was prepared by attaching an LED of 20 mm x 20 mm horizontally and vertically to the heat dissipation unit as a heat source using a TIM (thermal conductive tape: 1W/mk). Heat was generated by applying an input power of 2.1W (DC 3.9V, 0.53A) to the heat source of the prepared specimen, and after holding for 90 minutes, the temperature of the upper 5cm point of the center of the heat dissipation unit was measured to evaluate the heat emissivity. Specifically, the thermal emissivity was calculated according to Equation 2 below based on the temperature measured under the same conditions for the substrate not provided with the insulating heat dissipation coating layer.

[Equation 2]

3. Evaluation of uniformity of heat dissipation performance

After placing the heat dissipation unit in the center of the acrylic chamber, which is 32 cm x 30 cm x 30 cm in height, width, height, and height, adjust the temperature inside the chamber and the temperature of the heat dissipation unit to 25±0.2℃ and the humidity inside the chamber to 50% I did. Thereafter, a test specimen was prepared by attaching an LED of 20 mm x 20 mm horizontally and vertically to the heat dissipation unit as a heat source using a TIM (thermal conductive tape: 1W/mk). Generate heat by applying an input power of 2.1W (DC 3.9V, 0.53A) to the heat source of the manufactured specimen, and after holding it for 90 minutes, an arbitrary circle with a radius of 15mm centered on the center of the upper surface of the heat dissipation unit By measuring the temperature at 10 points of, the error of the heating temperature was calculated according to Equation 3 below. The smaller the error is, the more uniform the heat dissipation performance can be, and it can be interpreted that the dispersibility of the heat dissipation filler of the insulating heat dissipation coating layer is higher. The maximum values among the errors of the heating temperature are shown in Tables 1 to 3 below.

[Equation 3]

4. Durability evaluation

After 480 hours elapsed after placing the heat dissipation unit in the chamber at a temperature of 60°C and a relative humidity of 90%, the surface condition of the heat dissipation unit was visually evaluated. As a result of the evaluation, the presence or absence of cracks and peeling (floating) of the insulating heat-dissipating coating layer was checked, and if there was no abnormality, it was indicated as ○ and if abnormality occurred, it was expressed as ×.

5. Adhesion evaluation

The specimens for which the durability was evaluated were cross-cut with a knife so as to be 1 mm apart. After that, attach the scotch tape to the cut surface and pull it at an angle of 60° to check the state in which the insulating heat dissipation coating layer is peeled off. The evaluation criteria were evaluated according to ISO 2409. (5B: 0%, 4B: 5% or less, 3B: 5 to 15%, 2B: 15 to 35%, 1B: 35 to 65%, 0B: 65% or more)

6. Surface quality evaluation

In order to check the surface quality of the heat dissipation unit, it was checked whether there was a bumpy or rough feeling by touching the surface with hands. When there is a smooth feeling 5, When the area of the rough feeling is less than 2% of the total outer surface of the heat dissipation unit 4, When the area is more than 2% and less than 5% 3, When the area is more than 5% and less than 10% 2, the area exceeding 10% and less than 20% is represented as 1, and the area exceeding 20% is represented as 0.

division Example
One Example
2 Example
3 Example
4 Example
5 Example
6 Example
7 Coating layer forming component Subject balance
(Weight average molecular weight) 2000 2000 2000 2000 2000 2000 2000 Hardener content
(Part by weight) 60 60 60 60 60 60 60 Weight ratio of the first curing agent and the second curing agent 1:1 1:1 1:1 1:0.2 1:0.6 1:1.4 1:2 Insulating heat dissipation filler content
(Part by weight) 47 35 60 47 47 47 47 Average particle diameter (㎛) 5 5 5 5 5 5 5 D50, D97 ratio 1:1.6 1:1.6 1:1.6 1:1.6 1:1.6 1:1.6 1:1.6 Heat dissipation unit Insulating heat dissipation coating layer thickness (㎛) 25 25 25 25 25 25 25 Thermal conductivity (%) 18.27 17.65 18.34 16.94 17.72 17.63 17.01 Heat radiation efficiency (%) 90 81 96 86 88 89 88 Heating temperature error (%) 0.5 0.6 0.4 0.5 0.5 0.5 0.5 Adhesiveness 5B 5B 5B 0B 5B 5B 2B durability ○ ○ ○ x ○ ○ x Surface quality 5 5 5 5 5 5 5

division Example
8 Example
9 Example
10 Example
11 Example 12 Example 13 Coating layer forming component Subject balance
(Weight average molecular weight) 2000 2000 2000 2000 2000 2000 Hardener content
(Part by weight) 60 60 60 60 60 60 Weight ratio of the first curing agent and the second curing agent 1:1 1:1 1:1 1:1 1:1 1:1 Insulating heat dissipation filler content
(Part by weight) 47 47 47 47 47 47 Average particle diameter (㎛) 0.005 0.42 10 20 3 5 D50, D97 ratio 1:2.41 1:2.08 1:1.51 1:1.93 1:3.08 1:4.96 Heat dissipation unit Insulating heat dissipation coating layer thickness (㎛) 25 25 25 25 25 25 Thermal conductivity (%) 12.11 17.63 17.92 17.19 17.88 18.31 Heat radiation efficiency (%) 7 88 91 90 81 39 Heating temperature error (%) 0.5 0.5 0.4 2.8 0.8 3.9 Adhesiveness 3B 5B 5B 3B 4B 2B durability ○ ○ ○ ○ ○ ○ Surface quality 5 5 4 0 4 3

division Comparative Example 1 Comparative Example 2 Comparative Example 3 ¹⁾ Coating layer forming component Subject balance
(Weight average molecular weight) 2000 2000 2000 Hardener content (parts by weight) 60 60 60 Weight ratio of the first curing agent and the second curing agent 1:1 1:1 1:1 Insulating heat dissipation filler Content (parts by weight) 15 80 - Average particle diameter (㎛) 5 5 - D50, D97 ratio 1:1.6 1:1.6 - Heat dissipation unit Insulating heat dissipation coating layer thickness (㎛) 25 25 25 Thermal conductivity (%) 14.62 18.36 4.76 Heat radiation efficiency (%) 8 98 2 Heating temperature error (%) 5.3 1.0 0 Adhesiveness 5B 3.8 5B durability ○ × ○ Surface quality 5 One 5 1) Comparative Example 3 shows a composition that does not contain a heat dissipating filler.

As can be seen in Tables 1 to 3 above, Examples 1, 5, and 6 in which the weight ratio of the first curing agent and the second curing agent are within the preferred range of the present invention are not satisfied in Examples 2 and 5 In comparison, it can be seen that adhesion and durability are achieved at the same time.

In addition, it can be seen that the thermal radiation efficiency, thermal conductivity, and surface quality are simultaneously achieved compared to Examples 8 and 11 in which Examples 1, 9, and 10 in which the average particle diameter of the insulating heat-radiating filler is within the preferred range of the present invention are not satisfied have.

In addition, it can be seen that the ratios of D50 and D97 are within the preferred range of the present invention, as compared to Example 13, which does not satisfy this, dispersibility, surface quality, heat radiation efficiency, and adhesion are simultaneously achieved. .

In addition, it can be seen that Examples 1, 2, and 3, in which the content of the heat dissipating filler is within the preferred range of the present invention, are significantly superior in heat dissipation performance and surface quality at the same time as compared to Comparative Examples 1 and 2 which do not satisfy this.

In addition, it can be seen that Comparative Example 3, which does not contain a heat dissipating filler, has significantly lower thermal radiation compared to Example 1.

The LED modules 100, 200, and 300 according to the present invention described above may be installed both indoors or outdoors where lighting is required. For example, the LED modules 100, 200, and 300 may be installed outdoors such as parking lots or tunnels, and used as street lights, security lights, transmission lights, and lighting, and may also be used as indoor lights installed in offices or residential spaces.

Although an embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiment presented in the present specification, and those skilled in the art who understand the spirit of the present invention can add components within the scope of the same idea It will be possible to easily propose other embodiments by changing, deleting, adding, etc., but it will be said that this is also within the scope of the present invention.

100,200,300: LED module 110: light source
111: LED 112: circuit board
120: heat sink 126: insulating heat dissipation coating layer
130: protective cover 131: convex portion
132: accommodation space 150,250,350: air vent means
151: moving path 152: vent member

Claims (11)

A light source unit including a plurality of LEDs mounted on one surface of the circuit board;
A heat sink including a base substrate made of a metal material to support the light source unit and dissipate heat generated from the light source unit, and an insulating heat dissipation coating layer applied to an outer surface of the base substrate;
A protective cover coupled to one surface of the heat sink to protect the light source unit from an external environment; And
An internal space formed between the circuit board and the protective cover facing each other;
At least one protrusion protruding from one surface of the protective cover and
At least one air vent means for maintaining the internal pressure of the internal space and the external air pressure in an equilibrium state by performing the role of a passage through which air in the internal space can move to the outside;
The at least one protrusion forms the inner space by maintaining a gap between one surface of the protective cover and the circuit board when the protective cover and the heat sink are coupled,
The light source unit is electrically connected to an external power source through a connector to which a cable is connected,
The cable is connected to a cable fastener having a middle length detachably coupled to the heat sink,
The air vent means includes a moving path formed through the cable fixture to communicate with the inner space, and a vent member attached to one surface of the cable fixture to cover the moving path. delete The method of claim 1,
The heat sink includes a plate-shaped radiating fin protruding from the base material in one direction,
The LED module, wherein the radiating fin is formed with at least one protrusion to increase a contact area with external air. The method of claim 1,
The protective cover includes a convex portion formed to be convex upward in an area corresponding to each of the plurality of LEDs,
Each of the plurality of convex portions has an accommodation space for accommodating the LED on a surface facing the LED,
The receiving spaces respectively formed in the plurality of convex portions are LEDs communicating with each other through the inner space so that the air heated by the light emission of the LED can flow along the inner space and then be discharged to the outside through the air vent means module. delete The method of claim 1,
The vent member is an LED module made of a membrane material having breathability and moisture permeability. delete The method of claim 1,
The insulating heat dissipation coating layer includes a coating layer forming component including a main resin; And
LED module comprising; an insulating heat dissipation filler contained in an amount of 25 to 70 parts by weight based on 100 parts by weight of the main resin. The method of claim 8,
The insulating heat dissipation filler is an LED module comprising silicon carbide. The method of claim 9,
The insulating heat dissipation filler has an average particle diameter of 10 nm to 15 μm, and an LED module having a ratio of D50 and D97 of 1:4.5 or less (here, D50 and D97 are insulating properties when the cumulative degree is 50% and 97%, respectively, in the volume cumulative particle size distribution. It means the particle size of the heat dissipating filler). An LED lighting device comprising the LED module according to any one of claims 1, 3, 4, 6, and 8 to 10.

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