KR101203053B1 - Aluminium Laminating Bottom Chassis Having High Heat Radiation Efficiency for LED TV and Manufacturing Method of the Same - Google Patents

Abstract

The present invention relates to a bottom chassis for accommodating a backlight unit in an LED television and a method for manufacturing the same, and to provide heat dissipation while using existing CR, GI, and EG steel sheets.
To this end, the present invention, the LED array 61 is arranged a plurality of LEDs, the PCB (PCB) 63 for controlling the light emission of the LED array, and the reflective sheet 62 formed on the front of the PC 63 In the bottom chassis 70 for LED TVs accommodating the led module 60, the bottom chassis 70 includes a cold rolled steel sheet layer 71 formed of any one of CR, GI, and EG steel sheets. And a pretreatment agent layer 72 applied on the upper surface of the cold rolled steel sheet layer 71, an adhesive layer 73 formed on the top surface of the pretreatment agent layer 72, and an upper surface laminating of the adhesive layer 72 ( It characterized in that it comprises a laminating aluminum foil (Foil) layer (74).

Description

Aluminum Laminating Bottom Chassis Having High Heat Radiation Efficiency for LED TV and Manufacturing Method of the Same}

The present invention relates to a bottom chassis for accommodating a backlight unit in an LED television and a manufacturing method thereof, and more particularly, to one surface of a cold rolled steel sheet such as a cold roll (CR), galvanizing (GI), and electronic galvanizing (EG). The present invention relates to a high heat dissipating aluminum laminating bottom chassis capable of securing high heat dissipation performance by laminating an aluminum foil on a substrate, and a method of manufacturing the same.

Conventional televisions (hereinafter referred to as "TVs") mostly use cathode ray tubes (CRTs) (also called CRTs).

The cathode ray tube used as the receiving tube of a TV consists of a glass vacuum container, the electron gun which emits an electron beam, a deflector, the fluorescent surface which is a display part, etc.

The electron gun focuses electrons emitted from the cathode to make an electron beam, and the electron beam is deflected according to an electrical signal applied to the deflection coil to display an image on a fluorescent surface.

The cathode ray tube has been used in various industrial fields, such as not only a TV receiver tube, but also a measuring tube, a radar tube used for radar, an accumulation tube for temporarily storing waveforms and images, and a computer monitor.

However, in recent years, TVs using such cathode ray tubes are gradually disappearing, and so-called flat-panel TVs having a thin flat display device have been in the spotlight.

In addition, the display device used in flat-panel TVs is increasingly larger in size, and the thickness thereof is becoming thinner due to the preference of a wall-mounted TV.

Currently, display devices used in flat panel TVs include a plasma display device (PDP), a liquid crystal display (LCD), and a display using a light emitting diode (LED).

In the above-described plasma display device (hereinafter, simply referred to as 'PDP'), a positive electrode and a negative electrode are placed between a front glass and a rear glass and a glass sealed by a partition therebetween, such as Ne + Ar and Ne + Xe. A voltage is applied by an electrode of to emit neon light.

In other words, the PDP uses gas discharge generated by filling gas and applying a voltage between opposite and opposite electrodes.

The PDP is a so-called light emitting display that emits light by itself, and can easily display a large screen, has a high response speed, high reliability, and long life.

In addition, it has the advantages of comfortable eyes, smooth screen and high resolution, but has a disadvantage of relatively high power consumption and heat dissipation.

On the other hand, a liquid crystal display (hereinafter referred to as "LCD") is a device for displaying information by using the electrical and optical properties of the liquid crystal material injected into the liquid crystal display panel, in recent years, not only TV but also monitors of computers, It is widely used in various information and communication devices such as portable video cameras and digital cameras.

The LCD receives an image signal from an information processing apparatus, converts the image signal into a liquid crystal control signal, and adjusts the amount of light transmitted through the liquid crystal to visually recognize an image signal of an electrical form.

In other words, the light passing through the liquid crystal formed from the liquid state of the device through the back, the screen has a clear and clear advantage, but the eye is easily tired and the sharpness varies greatly depending on the location.

Since the LCD is a so-called light-receiving display that cannot emit light by itself, a separate light source is required, and such a separate light source is called a backlight unit.

As such a backlight unit, there is a Cold Cathod Fluorescent Lamp (CCFL).

The cold cathode fluorescent lamp projects the light generated from the lamp onto the liquid crystal display through the diffusion plate.

An LCD TV using a cold cathode fluorescent lamp includes a light guide plate for transmitting light generated from a fluorescent lamp as a light source, a reflection plate for reflecting light transmitted from the light guide plate to a liquid crystal screen, a diffusion plate laminated on the upper surface of the light guide plate, A plate, a protective plate, and the like.

Components of the LCD TV are housed inside the chassis for protection from external shocks. The chassis includes a bottom chassis that accommodates a backlight unit and a top chassis that accommodates a liquid crystal display panel.

The top chassis is mainly made of a metal material such as aluminum alloy or stainless steel to protect the liquid crystal panel and to prevent the separation of the backlight unit components.

The bottom chassis is mainly made of an electrogalvanized steel sheet called EG (Electronic Galvanizing) material to protect and reinforce the entire rear surface of the liquid crystal panel and the backlight unit.

However, the cold cathode fluorescent lamp (CCFL) used in the backlight unit of the LCD TV is subject to environmental regulations because it contains harmful mercury to the human body and requires a wire for connection with the inverter, .

In addition, the cold-cathode fluorescent lamp has a disadvantage in that it is weak in vibration and impact and invisible in terms of color reproducibility.

Recently, LEDs are used as a light source of a backlight in order to overcome these disadvantages.

That is, the LED TV uses a light emitting diode (Light Emitting Diode) as a light source of the backlight in the LCD TV.

Since the LED has high light conversion efficiency, power consumption is very low, and there is an advantage in that the LED can be miniaturized, thinned, and lightweight.

In addition, LED has a big advantage that it has a long lifespan, no gas or filament, and strong against shock and safe, and since it does not use mercury or gas for discharge, it is more environmentally friendly than PDP and LCD.

In addition, the LED is capable of high-speed response, and the brightness or color can be freely changed by adjusting the amount of red, green, and blue LEDs, thereby providing excellent color reproducibility.

Due to the above-mentioned advantages, LEDs have recently been used not only for display devices, but also for various signs, automobiles, traffic lights, and general lighting.

In particular, it is recently attracting a lot of attention as a light source of the backlight used in small devices such as mobile phones, navigation, PMP, the use range is expected to expand gradually in the future.

LED TVs that use these LEDs as backlights have the advantages of being brighter, clearer and using less electricity than conventional PDP or LCD TVs.

In particular, since the size of the LED itself is small, the LED TV can reduce the thickness of the backlight unit, and thus has the advantage of satisfying the recent consumer desire for a TV with a large screen and a thin thickness.

The disadvantage of LED TV is that it is expensive, but it is expected to lead the future TV market with 3D TV in the future.

In terms of the technological development of TV, it is expected to progress from the CRT (cathode ray tube) TV era to the PDP and LCD TV era, followed by the LED TV and 3D TV era.

The backlight unit applied to the LDE TV can be classified into a direct type in which LEDs are disposed on the entire rear side and an edge type in which LEDs are disposed only at corners.

The direct type backlight unit has a limitation in reducing the thickness of the backlight unit because it requires a certain distance between the LED and the diffusion plate in order to obtain uniform brightness and color uniformity.

There is an edge type backlight unit as a backlight unit to solve the above disadvantages.

The backlight unit has an advantage of having a thinner thickness than the direct type because the LED is disposed at the corners, but has a disadvantage in that heat generated from the LED is not sufficiently dissipated to the outside.

1 schematically shows a structure of a general LED TV employing a direct-type backlight unit.

As shown in FIG. 1, a general LED TV includes a LED module 60 in which a plurality of LEDs are disposed, and a diffusion sheet provided on an upper portion of the LED module to mitigate unbalance of light generated from the LED module 60 ( 50), the prism sheet 40 is provided on the diffusion sheet 50 to increase the brightness by collecting light, the protective sheet 30 to protect the prism sheet 40 and increase the viewing angle, the upper portion of the protective sheet A liquid crystal panel 90 provided at the top chassis, a top chassis 20 provided on and supporting the liquid crystal panel 90, a front cover 10 provided at a front surface of the top chassis 20, The bottom chassis 70 is provided below and supports the LED module 60, and the rear cover 80 is provided on the rear surface of the bottom chassis 70.

The LED module 60 includes an LED array 61 in which a plurality of LEDs are arranged, a printed circuit board 63 for controlling the LED array 61, And a reflective sheet 62 provided on the front surface of the light guide plate 62.

The PCB 63 includes an electrode unit (not shown) and a circuit for controlling the LED array 61 to transmit control signals to the respective LEDs. Thus, the PCB 63 controls the emission of red light, green light and blue light through the control circuit and the electrode part.

The diffusion sheet 50 is disposed at a predetermined distance from the LED array 61 so that the light emitted from the LED array 61 has a uniform distribution and the reflection sheet 62 is disposed at a predetermined distance from the LED array 61, And reflects light reflected toward the PCB 63 without being transmitted through the diffusion sheet 50.

Light generated from the LED array 61 and transmitted through the diffusion sheet 50 is incident to the liquid crystal panel 90 through the prism sheet 40 and the protection sheet 30, and does not penetrate the diffusion sheet 50. The light incident to the PC 63 is not reflected back by the reflective sheet 62.

The lower surface of the bottom chassis 70 disposed below the LED module 60 is provided with an LED driving IC chip (not shown), a connector (not shown), etc. for driving the LED array.

The present invention relates to an aluminum laminating steel sheet used in the bottom chassis 70 for accommodating and supporting the LED module in the LED TV having the above-described structure.

An EG (Electronic Galvanizing) steel sheet is known as a material of the bottom chassis.

The EG steel sheet is most widely used in existing LCD TVs using a cold cathode fluorescent lamp (CCFL) as a backlight unit.

Since the thickness of the LCD TV is thicker than that of the LED TV, even if the EG steel sheet described above is used as the bottom chassis 70, the heat dissipation is not a problem. In addition, when the TV screen is small, heat dissipation did not matter.

However, as the recent trend of TVs has shifted from LCD TVs to LED TVs, the heat dissipation performance of TVs has emerged as a very important problem due to the trend toward larger and slimmer screens.

In other words, since the LED TV screen is getting larger due to the development of LED-related technology, the heat generated from the TV is rapidly increased. If the heat generated inside the TV is not discharged to the outside, the afterimage may occur on the screen, thereby degrading the quality of the screen and adversely affecting various electrical components.

Therefore, it is important to secure heat dissipation performance and to efficiently dissipate heat generated inside the TV in a large sized and slimmed flat panel TV.

In order to secure the heat dissipation performance of the TV, it is necessary to secure a certain space. In recent years, the TV becomes a problem because the thickness is rather thin.

Furthermore, as the size of the screen and the slimmer of the TVs are expected to accelerate further, the problem of securing heat dissipation performance is expected to be intensified.

In order to solve this problem, an aluminum material has been proposed as a material of the bottom chassis of the LED TV. Since the aluminum material is excellent in heat dissipation performance, there is an advantage that it is suitable for a large size slim LED TV.

However, using aluminum as the bottom chassis of LED TVs has the following problems.

First, there is a problem that aluminum material is very expensive compared to the existing galvanized steel sheet.

In particular, as the size of the bottom chassis is gradually increasing as the size of the recent TV is getting bigger, there is a problem that the manufacturing cost of the bottom chassis is greatly increased when aluminum is used as the material of the bottom chassis.

Second, there is a problem that stable supply of aluminum material is difficult in Korea.

At present, there are not many companies manufacturing aluminum in Korea, and most of the aluminum is dependent on imports, so the supply and demand is very unstable.

Therefore, in order to mass-produce LED TVs, aluminum materials must be continuously and stably supplied, but in reality, there is a serious problem of this.

As is well known, international raw materials such as aluminum have a disadvantage in that the price fluctuations are large and they are not smooth even in the supply and demand, unlike in the case of a general steel sheet.

As a result, unless a stable supply of aluminum material is secured, it is difficult to mass-produce large LED TVs.

In other words, in order to manufacture a large-scale LED TV, a bottom chassis cannot use a conventional EG steel sheet, and thus an aluminum material should be used.

The present invention has been proposed to solve the above problems of the prior art, and an object thereof is to provide a material that can replace the bottom chassis of aluminum materials used in large-size LED TV.

Another object of the present invention is to ensure a heat dissipation performance while using a CR, GI, EG steel sheet, etc. in a large LED TV.

Still another object of the present invention is to reduce the manufacturing cost of the bottom chassis.

Another object of the present invention to build a mass production system of LED TV by using a material that can stably supply the bottom chassis material.

The high heat dissipation aluminum laminating bottom chassis of the present invention for achieving the above object, the LED array (LED Array) in which a plurality of LEDs are arranged, the PCB (PCB: Printed Circuit Board) for controlling the light emission of the LED array, In a bottom chassis for LED televisions containing an LED module consisting of a reflective sheet formed on the front surface of the PC, the bottom chassis is applied to the cold rolled steel sheet layer made of any one of CR, GI, EG steel sheet and the upper surface of the cold rolled steel sheet layer It characterized in that it comprises a pretreatment agent layer, an adhesive layer applied to the upper surface of the pretreatment agent layer, and an aluminum foil layer (Laminating) of the upper surface of the adhesive layer.

In addition, the aluminum foil layer is characterized in that the thin plate layer of 50 ~ 200㎛ thickness formed by extruding 1000 series aluminum several times.

In addition, the adhesive applied to the adhesive layer is produced by using a thermoplastic polyurethane (TPU: Thermoplastic Polyurethane) resin and an epoxy resin as main components and an isocyanate as a curing agent.

In addition, the number average molecular weight (Mn) of the thermoplastic polyurethane resin is characterized in that 1,000 to 10,000.

In addition, the number average molecular weight (Mn) of the epoxy resin is characterized in that 15,000 ~ 35,000.

In addition, the anti-fingerprint layer is further formed on the opposite surface on which the aluminum foil layer is formed.

Meanwhile, the method of manufacturing a bottom chassis for an LED TV according to the present invention includes preparing a cold rolled steel sheet of any one of CR, GI, and EG steel sheets, applying a pretreatment agent to the cold rolled steel sheet, and applying an adhesive on the pretreatment agent. The step of applying, the adhesive and curing in a hot air oven, characterized in that it comprises a step of laminating the aluminum thin layer after curing is completed.

According to the present invention, there is an effect that can replace the aluminum material used as the bottom chassis of the LED TV that is becoming larger, slimmer.

In addition, while using a CR, GI, EG steel plate as the material of the bottom chassis of a large LED TV, it is possible to secure heat dissipation performance similar to that of aluminum.

Accordingly, there is an effect of preventing the phenomenon in which afterimages occur on the screen due to deterioration of the heat radiation performance and adversely affect the electrical components.

In addition, by using the existing CR, GI, EG steel sheet in a large LED TV, it is possible to reduce the manufacturing cost of the bottom chassis, and to effectively cope with supply and demand problems caused by the import of aluminum raw materials.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows a configuration of a general LED TV; FIG.
2 shows a bottom chassis in accordance with the present invention;
3 is a sectional view taken along the line AA in Fig.

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

Since the description of the general structure of the LED TV has been described in the background art above, only the bottom chassis, which is a feature of the present invention, will be described.

The bottom chassis 70 according to the present invention is applied to a cold rolled steel sheet layer 71 made of any one of a cold roll (CR), galvanizing (GI), and electronic galvanizing (EG) steel plate, and an upper surface of the cold rolled steel sheet layer 71. The pretreatment agent layer 72 layer, the adhesive layer 73 formed on the upper surface of the pretreatment agent layer 72, and the aluminum foil layer 74 laminated on the upper surface of the adhesive layer 72. ).

The present invention is characterized in that it is used as a material of the bottom chassis of the LED TV by laminating an aluminum foil on a conventional CR, GI, EG steel sheet.

The adhesive applied to the adhesive layer 73 is produced by using a thermoplastic polyurethane (TPU: Thermoplastic Polyurethane) resin and an epoxy resin as main components and isocyanate as a curing agent.

In the adhesive, the number average molecular weight (Mn) of the thermoplastic polyurethane resin is preferably 1,000 to 10,000. Moreover, it is preferable that the number average molecular weights (Mn) of the said epoxy resin are 15,000-35,000.

The aluminum foil layer is formed by laminating a pressing roll as a thin plate layer having a thickness of 50 to 200 μm formed by extruding 1000 series aluminum several times.

In addition, the anti-fingerprint layer 75 may be further formed on the opposite surface on which the aluminum foil layer 74 is formed.

Hereinafter, the manufacturing process of the bottom chassis for LED TV according to the present invention.

First, a cold rolled steel sheet of any one of CR, GI, and EG steel sheets is prepared. Since the CR, GI, EG steel sheet is widely produced in Korea, there is no problem in supply and demand of materials.

Subsequently, a pretreatment agent is applied to the cold rolled steel sheet at about 100 mg / m ² . The pretreatment improves the adhesion between the cold rolled steel sheet and the adhesive.

Next, the adhesive is coated with 10 µm or more and placed in a hot air oven to cure at about 180 ° C of PMT (Peak Metal Temperature).

After curing is completed, the aluminum foil is laminated with a pressing roll to complete the manufacture of the bottom chassis for the LED TV.

Since the laminating process is a well-known process, a detailed description thereof will be omitted.

The aluminum foil is a thin plate formed by extruding 1000 series aluminum several times and preferably has a thickness of 50-200 μm.

According to the test results, the heat dissipation performance is lowered when the thickness of the aluminum foil is 50 μm or less, and the heat dissipation performance is not much improved compared to the thickness when the thickness of the aluminum foil is 200 μm or more.

Therefore, the thickness of the aluminum foil is preferably 50-200㎛.

In addition, as a result of comparing the heat dissipation performance of the bottom chassis manufactured by the present invention and the bottom chassis made of aluminum, the heat dissipation performance of the bottom chassis manufactured by the present invention was found to be close to the heat dissipation performance of the aluminum material.

In particular, when the size of the bottom chassis is large, it was confirmed that the heat dissipation performance of the bottom chassis of the present invention and the bottom chassis of the aluminum material does not have a large difference. This is presumably because the expansion of the heat dissipation area affects the heat dissipation performance.

The biggest feature of the present invention is to escape from the idea that aluminum is the only material of the bottom chassis of a large-sized, slimmer LED TV, and similar heat dissipation performance by laminating aluminum foil on existing CR, GI and EG steel sheets. It is secured.

Accordingly, the existing CR, GI, EG steel sheet can be used as it is, it is possible to significantly reduce the manufacturing cost of the bottom chassis.

In addition, the supply and demand of aluminum, which is the biggest obstacle to mass production of large-size LED TVs, can be greatly alleviated, which can greatly contribute to the expected mass production of LED TVs.

Since Korea relies mostly on imports, it has a fatal problem that it cannot secure stable supply of aluminum, rather than the burden of rising raw material prices.

For this reason, the current large LED TV manufacturers are unable to build a large production line, although the demand for large LED TVs will expand in the future.

According to the present invention, since the EG steel sheet, which has not been used in a large LED TV, can still be used as it is, it is possible to fundamentally solve the problem of price increase and supply and demand instability caused by the use of an aluminum material.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these specific embodiments. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It should be interpreted.

The present invention is to ensure the heat dissipation performance by using an aluminum foil laminated on the CR, GI, EG steel sheet as a material of the bottom chassis of the LED TV, it can be widely used in the field of LED TV manufacturing.

10: front cover 20: top chassis
30: protective sheet 40: prism sheet
50: diffusion sheet 50: LED module
61: LED array 62: reflective sheet
63: PCB (PCB) 70: Bottom Chassis
71: cold rolled steel sheet layer 72: pretreatment layer
73: adhesive layer 74: aluminum foil (Foil) layer
80: back cover

Claims (7)

LED array 61 in which a plurality of LEDs are arranged, a printed circuit board (PCB) 63 for controlling light emission of the LED array, and a reflective sheet formed on the front of the PCB 63 ( In the bottom chassis (70) for the LED television receiving the LED module 60 consisting of 62,
The bottom chassis 70 is a cold rolled steel sheet layer 71 formed of any one of a cold roll (CR), galvanizing (GI), and an electronic galvanizing (EG) steel sheet, and a pretreatment layer applied to an upper surface of the cold rolled steel sheet layer 71. (72), an adhesive layer (73) formed on the upper surface of the pretreatment agent layer (72), and an aluminum foil layer (74) laminated on the upper surface of the adhesive layer (73). and,
The aluminum foil layer 74 is composed of a thin layer of 50 ~ 200㎛ thickness formed by extruding 1000 series aluminum several times,
The adhesive applied to the adhesive layer 73 includes a thermoplastic polyurethane (TPU: Thermoplastic Polyurethane) resin, an epoxy resin and an isocyanate which is a curing agent.
The number average molecular weight (Mn) of the thermoplastic polyurethane resin is 1,000 to 10,000,
The number average molecular weight (Mn) of the said epoxy resin is 15,000-35,000,
Bottom chassis for LED television, characterized in that the anti-fingerprint layer (75) is further formed on the opposite side on which the aluminum foil layer (74) is formed. delete delete delete delete delete delete

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