KR20170136365A - Display module and electronic device including the same - Google Patents

Abstract

Provided is a display module. According to an embodiment of the present invention, the display module includes: a display panel; a metal radiating sheet attached to a side of the display panel to disperse heat generated from an electronic device; a circuit substrate electrically connected with the display panel, and placed on a side of the radiating sheet; and a conductive thermal reaction adhesion layer applied to a side of the radiating sheet. The conductive thermal reaction adhesion layer includes a conductive filler for carrying current between the radiating sheet and the circuit substrate, and adhesive force at no less than 60C is able to be relatively smaller than adhesive force at 25C. As such, if the display module is applied to a smartphone, noise on the phone is removed or reduced, and the display panel and the radiating sheet are conveniently separated during a rework procedure without any damage.

Description

Display module and an electronic device including the same [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display module, and more particularly, to a display module and a portable electronic device including the display module.

Recently, with the spread of portable information communication devices such as mobile phones, smart phones, tablet PCs, and the like, demand for thinner, lighter and wider screen portable electronic devices is increasing.

This is related to the integration of electronic circuits and the improvement of flat panel display panels such as LCD, OLED, and PDP. However, since such a flat panel display panel is very vulnerable to impact, mechanical design for preventing breakage due to impact is indispensable.

Accordingly, in order to protect the display panel which is vulnerable to an external impact, a reinforcement member such as a window bracket is usually attached to the main body of the electronic apparatus to prevent breakage of the display panel.

That is, the window bracket is bonded to the display panel on the front or partially so that the display panel is not moved independently even when an external impact is applied, thereby protecting the display panel from external impacts.

To this end, the window bracket is made of a metal material such as magnesium or aluminum, or a plastic material such as polycarbonate or polyamide.

However, the display panel is fixed to the window bracket via the adhesive or fixed to the window bracket via the heat-radiating sheet for heat radiation. Accordingly, in the process of performing the rework process in the case where the parts are damaged during the use process or the defective product is present at the time of the first assembly, the display panel or the heat radiation sheet is not easily separated from the window bracket, There is a problem that the heat-radiating sheet or the display panel is damaged.

KR 10-2013-0102812 A

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a display module capable of easily performing a rework process without damaging a product by having a pressure sensitive adhesive applied to one surface of a heat- The present invention is directed to a portable electronic device.

According to an aspect of the present invention, there is provided a display device comprising: a display panel; A heat dissipation sheet attached to one surface of the display panel and made of a metal material so as to disperse heat generated from the electronic device; A circuit board electrically connected to the display panel and disposed on one surface of the heat-radiating sheet; And a conductive heat-sensitive adhesive layer applied to one surface of the heat-radiating sheet, wherein the conductive heat-sensitive adhesive layer comprises a conductive filler for conducting the circuit board and the heat-radiating sheet, The display module having a size relatively smaller than the adhesive force at 25 [deg.] C.

The conductive filler may be a silver powder or a nickel powder.

The conductive filler may be present in an amount of 1 to 10 wt% based on the total weight of the conductive heat-reactive adhesive layer.

In addition, the conductive heat-sensitive adhesive layer may have an adhesive strength at a temperature of 60 ° C or higher to 50% or lower with respect to an adhesive strength at 25 ° C.

The heat-radiating sheet may be made of copper.

An auxiliary heat-radiating sheet for heat dissipation may be disposed between the heat-radiating sheet and the display panel.

The auxiliary heat-radiating sheet may be made of a material including at least one of graphite and metals other than copper.

In addition, the circuit board may be attached to the heat-radiating sheet via the conductive heat-reactive adhesive layer.

In addition, the heat-radiating sheet may be directly attached to the metal bracket of the main body of the electronic apparatus via the conductive heat-reactive adhesive layer in a region other than the circuit board.

Meanwhile, the present invention provides a portable electronic device including the above-described display module.

According to the present invention, the display module can be separated from the metal bracket without damaging the product during the rework process.

1 is a schematic view showing a portable electronic device to which a display module according to an embodiment of the present invention is applied,
FIG. 2 is a sectional view showing a display module applied to FIG. 1,
3 is a view showing a state before and after attachment of a circuit board and a heat radiation sheet in a display module according to an embodiment of the present invention,
4 is a cross-sectional view illustrating a state in which an auxiliary heat-radiating sheet is applied to a display module according to an embodiment of the present invention,

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

The display module 100 according to an exemplary embodiment of the present invention is applied to a portable electronic device such as a smart phone, a tablet, and a notebook computer to visualize signals transmitted from the circuit board 130 and display the signals on an image. 110, a circuit board 130, a heat radiation sheet 120, and a conductive heat-reactive adhesive layer 140.

However, the display module 100 according to the present invention is not limited thereto, and may be applied to a home appliance such as a TV, an audio or a refrigerator, a monitor of a PC, or a guide indicator installed in a bus stop, a subway station, .

The display panel 110 is for displaying an image by visualizing a signal transmitted from the circuit board 130. The display panel 110 may be a known liquid crystal display panel (LCD), an electroluminescence display panel (ELD), a field emission display panel (FED), a plasma display panel (PDP), a thin film liquid crystal display panel And an organic light emitting diode display panel (OLED).

The display panel 110 may be an organic light emitting diode (OLED) panel capable of touching a user.

That is, the display panel 110 recognizes a contact position and a position change when a human hand or an object touches the screen, identifies a gesture corresponding to the position change, and displays an operation command corresponding to the contact position or an operation corresponding to the gesture It may be a form capable of performing a function corresponding to the confirmed operation command after confirming the command and displaying an image thereon.

However, the present invention is not limited thereto. The display panel 110 may display an image corresponding to a user's operation command, recognize a contact position and a positional change when a human hand or an object touches the screen, And a known touch panel (not shown) for identifying the gesture may be separately provided.

An electronic circuit for driving the display panel 110 may be formed on the circuit board 130 by being electrically connected to the display panel 110 at one side. That is, the circuit board 130 confirms the position of the touch point based on the touch signal output from the display panel 110, confirms the icon displayed at the position of the confirmed touch point, And control the result of execution of the function to be displayed to the outside.

The circuit board 130 may be an FPCB having a circuit pattern formed on one side or both sides of the insulating substrate, and may be partially folded and disposed on the back surface of the display panel 110 (refer to FIG. 3).

In addition, the display module 100 may be disposed inside an external bezel 112 to form an exterior and protect the display module 100 from external environments (see FIG. 1).

The heat dissipation sheet 120 is attached to one surface of the display panel 110 to disperse heat generated from the electronic panel to which the display panel 110 or the display panel 110 is applied.

The heat-radiating sheet 120 may be made of a material having a high thermal conductivity. For example, the heat-radiating sheet 120 may be made of a material including at least one of copper, aluminum, and graphite. However, when the display module 100 according to the present invention is applied to a smartphone, Or may be made of a metal material.

The heat radiation sheet 120 may be attached to one side of the display panel 110 through an adhesive layer 122 and the adhesive layer 122 may include a thermally conductive component.

The conductive heat-sensitive adhesive layer 140 is coated on one surface of the heat-radiating sheet 120 to have a predetermined thickness and the display panel 110 having the heat- And the circuit board 130 folded back toward the back of the display panel 110 may be attached to the heat radiation sheet 120 side.

The conductive heat-sensitive adhesive layer 140 may be formed on the entire surface of the heat-radiating sheet 120 so that the circuit board 130 connected to the display panel 110 is folded on the back surface of the heat- The display panel 110 with the heat radiation sheet 120 attached thereto through the conductive heat-reactive adhesive layer 140 applied to the remaining part of the entire area of the heat radiation sheet 120 except for the area corresponding to the circuit board 130 Can be attached to the main body 10 of the electronic apparatus.

The main body 10 of the electronic apparatus may include a metal bracket 12 for physically supporting the display panel 110 to prevent damage to the display panel 110, Can be directly attached to the metal bracket 12 via the conductive heat-reactive adhesive layer 140. [ For example, when the electronic device is a smart phone, the electronic device includes the electronic device body 10 including the metal bracket 12, the battery 14, and the back cover 16, and the display module 100 according to the present invention. And the display module 100 may be attached to the metal bracket 12 via the conductive heat-reactive adhesive layer 140. [ In addition, it is noted that a separate circuit board may be additionally provided in the main body 10 of the electronic apparatus.

At this time, the conductive heat-sensitive adhesive layer 140 according to the present invention may be provided to have a difference in adhesive strength depending on the temperature. This is because it is possible to prevent damage to the display panel 110 and the heat dissipation sheet 120 when it is necessary to separate the display module 100 from the main body 10 of the electronic device due to a trouble during use of the electronic equipment, This is to facilitate work work.

That is, the conductive heat-sensitive adhesive layer 140 applied to the present invention may be composed of a composition having a cohesive strength at a temperature of 60 ° C or higher and a cohesion strength lower than that at 25 ° C.

For example, the conductive heat-sensitive adhesive layer 140 may have a cohesive strength at a temperature of 60 ° C or higher of 50% or less with respect to the cohesive strength at 25 ° C, and after a certain period of exposure at a temperature of 60 ° C or higher, It can recover to the level of 60 ~ 80% with respect to the original adhesive force. In addition, the conductive heat-sensitive adhesive layer 140 may have an adhesive strength at 25 ° C of 500 to 2500 gf / 25 mm and an adhesive strength at 60 ° C of 180 to 1250 gf / 25 mm.

As a concrete example, the conductive heat-sensitive adhesive layer 140 according to the present invention may have an adhesive strength according to the time of exposure at room temperature (25 ° C.) after being left at a temperature of 60 ° C. for a certain period of time, .

The following Table 1 shows the results of evaluation of the change of adhesive strength with time at a temperature of 25 ° C after KS (KS) was applied after leaving the conductive heat-reactive adhesive layer 140 having an adhesive strength of approximately 2000 gf / 25 mm at a temperature of 25 ° C. at a temperature of 60 ° C. for 10 minutes. This is the result of repeated measurement three times using a T 1028 standard.

60 ° C Temperature exposure time (sec) Room temperature (25 ° C) Exposure time (sec) Adhesion (gf / 25mm) Measure 1 Measure 2 Measure 3 x 1800 2080 2110 1980 600 30 520 520 550 60 540 550 570 180 870 800 880 300 1440 1470 1500 3600 1930 1990 1920

As shown in Table 1, the conductive heat-sensitive adhesive layer 140 according to an embodiment of the present invention can have an adhesive strength at 60 ° C of 50% or less with respect to an adhesive force at 25 ° C, After 10 minutes of exposure, it is possible to recover to 60 ~ 80% of the original adhesive strength after 5 minutes at 25 ° C.

However, the conductive heat-sensitive adhesive layer 140 according to the present invention is not limited thereto, and the adhesive strength at 25 ° C and 60 ° C may be appropriately changed depending on the thickness of the adhesive layer and the content of the filler. However, when the adhesive strength at a temperature of 60 ° C or higher is 50% or less with respect to the adhesive strength at 25 ° C, and after 5 minutes at 25 ° C after exposure for a certain time at a temperature of 60 ° C or higher, If it is a form that can be recovered, it is clear.

In this case, when the display module 100 according to the present invention is to be detached from the metal bracket 12 of the main body 10 of the electronic device, the portable electronic device is detached from the metal bracket 12 for a predetermined time (for example, about 10 minutes) The adhesive force of the conductive heat-sensitive adhesive layer 140 is reduced to 50% or less as compared with the adhesive strength at room temperature, so that the display module 100 with the heat-radiating sheet 120 attached thereto is easily separated from the metal bracket 12 . Accordingly, it is possible to prevent the heat-radiating sheet 120 and the display module 100 from being damaged by a strong adhesive force during the rewiring process.

For this purpose, the conductive heat-sensitive adhesive layer 140 may be formed of an acrylic copolymer resin composition comprising butyl acrylate, 2-hydroxyethyl acrylate (HEA), acrylic acid, rosin ester, and an additive.

For example, the conductive heat-sensitive adhesive layer 140 may include 35 to 45% by weight of butyl acrylate, 30 to 40% by weight of 2-hydroxyethyl acrylate (HEA), 3 to 5% by weight of acrylic acid, 20 to 30% by weight of rosin ester and 1 to 10% by weight of an additive.

At this time, the additive may include a conductive filler such that the adhesive layer 140 has conductivity, and the conductive filler may include at least one of two kinds of fillers having a D50 of 6 to 10 mu m or 1 to 3 mu m .

Here, nickel powder or silver powder may be used as the conductive filler. This is because the nickel powder or the silver powder can significantly improve the electrical conductivity of the conductive heat-sensitive adhesive layer 140 even in a small amount.

Accordingly, the conductive heat-sensitive adhesive layer 140 according to the present invention becomes conductive through the conductive filler, so that the circuit board 130 disposed on the back surface of the heat-radiating sheet 120 is electrically connected to the conductive heat- The heat dissipation sheet 120 made of a metal material is energized to remove or reduce noise. For example, when the display module 100 according to the present invention is applied to a portable terminal such as a smart phone, it is possible to reduce noise generated during a call. Here, the additive may further include one or more of known plasticizers, elastomers and catalysts in addition to the conductive filler.

Although the conductive heat-sensitive adhesive layer 140 is illustrated as being entirely applied to one side of the heat-radiating sheet 120, the present invention is not limited thereto, 130 may be applied only locally to the region corresponding to the area of the circuit board 130 and may be applied only to the region corresponding to the heat generating element mounted on the circuit board 130. [

Meanwhile, in the display module 100 according to the present invention, a separate auxiliary heat-radiating sheet 150 may be disposed between the heat-radiating sheet 120 and the display panel 110 to enhance heat dissipation (see FIG. 4). The auxiliary heat-radiating sheet 150 may be made of a material having excellent thermal conductivity such as a metal material such as aluminum or graphite.

The auxiliary heat-radiating sheet 150 may be made of the same material as the heat-radiating sheet 120, but may have a higher thermal conductivity than the heat-radiating sheet 120 to further enhance heat dissipation. For example, when the heat-radiating sheet 120 is made of a metal material so as to be electrically connected to the circuit board 130 through the conductive heat-reactive adhesive layer 140, the heat-radiating sheet 150 may be made of graphite.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary 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 by the appended claims.

100: display module 110: display panel
112: external bezel 120: heat-radiating sheet
122: adhesive layer 130: circuit board
140: conductive heat-reactive adhesive layer 150: auxiliary heat-radiating sheet
10: Electronic device body 12: Metal bracket
14: Battery 16: Back cover

Claims (10)

A display panel;
A heat dissipation sheet attached to one surface of the display panel and made of a metal material so as to disperse heat generated from the electronic device;
A circuit board electrically connected to the display panel and disposed on one surface of the heat-radiating sheet; And
And a conductive heat-sensitive adhesive layer applied to one surface of the heat-radiating sheet,
Wherein the conductive heat-sensitive adhesive layer includes a conductive filler for conducting electricity to the circuit board and the heat-radiating sheet, and the adhesive force at a temperature of 60 ° C or more is smaller than the adhesive force at 25 ° C. The method according to claim 1,
Wherein the conductive filler is silver powder or nickel powder. The method according to claim 1,
Wherein the conductive filler is 1 to 10 wt% based on the total weight of the conductive heat-reactive adhesive layer. The method according to claim 1,
Wherein the conductive heat-sensitive adhesive layer has an adhesive strength at 60 ° C or higher of 50% or less with respect to an adhesive strength at 25 ° C. The method according to claim 1,
Wherein the heat-radiating sheet is made of copper. The method according to claim 1,
And an auxiliary heat radiation sheet for heat dissipation is disposed between the heat radiation sheet and the display panel. The method according to claim 6,
Wherein the auxiliary heat-radiating sheet is made of a material including at least one of graphite and a metal other than copper. The method according to claim 1,
Wherein the circuit board is attached to the heat-radiating sheet via the conductive heat-reactive adhesive layer. The method according to claim 1,
Wherein the heat dissipation sheet is directly attached to the metal bracket of the main body of the electronic device through the conductive heat-sensitive adhesive layer in a region except for the circuit board. A portable electronic device comprising the display module according to any one of claims 1 to 9.

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