JP2000305064A - Protective sheet for liquid crystal module and liquid crystal module with protective sheet and method for protecting liquid crystal display part of liquid crystal module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective sheet for a liquid crystal module which does not generate a change of an optical color tone of the liquid crystal module even if it is preserved and kept in a state in which the surface of the display part of the liquid crystal module is covered with the surface protective sheet and besides not only the surface protective sheet but also the liquid crystal module, the coated body, is not charged when the surface protective sheet is released. SOLUTION: The protective sheet 10 for a liquid crystal module is obtained by forming a repeatedly releasable adhesive layer 12 for example in a square frame, belt-like shape in a region corresponding to a bezel (a fixed frame) of the liquid crystal module, the coated body, on one surface of a plastic substrate 11 having rigidity capable of maintaining a non-contact state with the surface of the display part of the liquid crystal module when mounted on it, composed of polyester, acrylic, polycarbonate or the like. Also the substrate 11 is subjected to antistatic treatment for example by being provided with an antistatic layer 13 on its one or both surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective sheet for a liquid crystal module, a liquid crystal module with a protective sheet, and a method for protecting a liquid crystal display of a liquid crystal module. In particular,
The present invention relates to a protection sheet for a liquid crystal module used in a liquid crystal display device used for a personal computer, a word processor, a television, and the like, a liquid crystal module provided with the protection sheet, and a method for protecting a liquid crystal display portion of the liquid crystal module.

[0002]

2. Description of the Related Art A liquid crystal display device used for a personal computer, a word processor, a television or the like has a liquid crystal section 2 composed of a glass substrate and liquid crystal, and a reflection plate 3 composed of aluminum or the like disposed on the back of the liquid crystal section 2. Various optical films 4 such as a polarizing film, a retardation film and an anti-reflection film are laminated, and the outer periphery thereof is fixed frame 5 made of a metal plate such as stainless steel called "Vessel".
Then, the liquid crystal module 1 is fixed to the liquid crystal module 1, and the liquid crystal module 1 is assembled and stored in a housing together with other components.

[0003] A surface protection sheet (film) is usually mounted on the display surface 6 of the liquid crystal module 1 in order to prevent the attachment or contamination of dust and the like during the assembly process and distribution process.

Conventionally, as the surface protective sheet, for example, as shown in FIG. 5, an adhesive sheet 51 in which a releasable adhesive layer 53 is formed on one entire surface of a flexible plastic film 52 is used. In some cases, the agent layer 53 was attached to the surface of the vessel 5 and the surface 6 of the display unit. Further, as shown in FIG. 6, a method of covering the display surface 6 with a protective sheet 55 made of a rigid plastic and fixing the periphery thereof with an adhesive tape has been adopted.

[0005]

However, when the adhesive sheet 51 is used as shown in FIG.
A region 54 where the pressure-sensitive adhesive sheet 51 cannot adhere to the display unit surface 6 occurs in a region along the inside of the image. As a result, if the adhesive sheet 51 is left under high humidity with the adhesive sheet 51 covered, an optical color change occurs between the area where the adhesive sheet 51 is in close contact with the display surface 6 and the area 54 where the adhesive sheet 51 is not in close contact. As a result, the reliability of the liquid crystal display device may be reduced.

Further, when the adhesive sheet 51 is used, the liquid crystal module 1 is charged when the surface protection sheet 50 is peeled off, and there is a problem that semiconductor devices and liquid crystals inside the liquid crystal module 1 are destroyed. Was. In such a case, an attempt has been made to prevent electrification by forming an antistatic layer on the surface protection sheet 50, but this method can suppress the electrification of the surface protection sheet 50 itself during peeling, Liquid crystal module 1 as body
Was incapable of charging.

On the other hand, when the protective sheet 55 made of plastic is used, the optical color tone does not change, but the mounting is troublesome and the workability is poor.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a liquid crystal module which can be stored and stored in a state in which a display unit surface is covered with a surface protection sheet. An object of the present invention is to provide a protective sheet for a liquid crystal module which does not cause an optical color tone change of the liquid crystal module and which does not charge not only the surface protective sheet but also the liquid crystal module as an adherend when the surface protective sheet is peeled off.

[0009]

A protective sheet for a liquid crystal module according to the present invention is a protective sheet for a liquid crystal module mounted on a liquid crystal module having a fixed frame around a liquid crystal display section. Characterized in that a re-peelable pressure-sensitive adhesive layer was formed on one side of a plastic base material having rigidity capable of maintaining a non-contact state with the surface of the liquid crystal module, which is an adherend, in a region corresponding to a fixed frame of the liquid crystal module. And

At this time, it is preferable that the plastic substrate is subjected to an antistatic treatment.

The liquid crystal module with a protective sheet according to the present invention includes a liquid crystal module having a fixed frame around a liquid crystal display portion and a liquid crystal module with a protective sheet for a liquid crystal module according to claim 1 or 2. The pressure-sensitive adhesive layer is attached to the fixing frame in a state where the base material of the liquid crystal module protective sheet does not contact the liquid crystal display of the liquid crystal module.

Further, the method for protecting a liquid crystal display portion of a liquid crystal module according to the present invention is a method for protecting the liquid crystal display portion of a liquid crystal module having a fixed frame around the liquid crystal display portion,
A plastic substrate having rigidity capable of maintaining a non-contact state with the surface of the liquid crystal display unit when attached is attached to the surface of the fixed frame using an adhesive while not in contact with the surface of the liquid crystal display unit. Features.

At this time, it is desirable that the pressure-sensitive adhesive is set so that the anchoring force between the pressure-sensitive adhesive and the base material is larger than the adhesive force between the pressure-sensitive adhesive and the fixing frame.

[0014]

FIG. 1 shows a protective sheet for a liquid crystal module (hereinafter referred to as a "protective sheet") according to an embodiment of the present invention.
Called. 3A is a schematic structural view, wherein FIG. 3A is a sectional structural view, FIG. 3B is a rear view thereof, and FIG. 2 is a liquid crystal according to an embodiment of the present invention equipped with the protective sheet. FIG. 3 is a schematic cross-sectional structural view of the module, FIG. 3 is a rear view of a protection sheet according to another embodiment, and FIG. 4 is a rear view of a protection sheet according to another embodiment. Hereinafter, the present invention will be described in detail with reference to the drawings.

The protective sheet 10 for a liquid crystal module according to the present invention has a substrate 11 made of a plastic sheet or film, and an adhesive layer 12 to be attached to the liquid crystal module 1.

The base material 11 is for coating the display surface 6 of the liquid crystal module 1, and can maintain a non-contact state with the display surface 6 during coating in order to prevent contact with the display surface 6. Those having a degree of rigidity are used. The required rigidity varies depending on the size of the display unit of the liquid crystal module 1 as the adherend. That is, as described below, when the peripheral portion of the protective sheet 10 is adhered to the vessel (fixed frame) 5 of the liquid crystal module 1, even when the central portion, which is particularly flexible, bends (see the broken line in FIG. 3). ,
What is necessary is just to have sufficient rigidity so as not to contact the surface 6 of the display unit. Therefore, the material of the base material 11 used depends on the required rigidity, and the material of the base material 11, its thickness, and the like are appropriately selected and determined according to the rigidity. The sheet or film in the present invention is used not only in terms of a so-called flexible sheet or film, but also in terms of a so-called plate-shaped material having higher rigidity. From the viewpoint of efficiency, a sheet or film having flexibility is more preferably used.

[0017] Therefore, the material is not particularly limited as long as the above object can be achieved. Examples thereof include polyester, acrylic, polycarbonate, polystyrene, hard vinyl chloride, polyethylene, and polypropylene. Alternatively, a film or sheet made of a blend of two or more kinds is used. In addition, the substrate 11 is not limited to a single-layer substrate made of these materials, and a substrate in which two or more sheets or films are laminated can be suitably used.

In addition, a material that can maintain a transparent or translucent state is preferably used so that the surface state of the display unit can be visually confirmed at the time of coating.

The protective sheet 10 is manufactured by forming an adhesive layer 12 at a predetermined position on the back side of the substrate 11. The pressure-sensitive adhesive layer 12 is attached to the surface of the vessel 5 constituting the liquid crystal module 1. Therefore, the pressure-sensitive adhesive layer 12 is set in accordance with the structure of the liquid crystal module 1 to be used, specifically, the size and position of the vessel 5. The vessel 5 is generally formed on all sides of the liquid crystal module 1 as described above. For example, in the protective sheet 10 shown in FIG.
It is formed in the shape of a square frame band on the periphery of the back surface. The width of the pressure-sensitive adhesive layer 12 is set substantially equal to or slightly smaller than the width of the vessel 5.

Since the protective sheet 10 is to be peeled again after it is once mounted on the liquid crystal module 1, a removable peelable adhesive is used as the adhesive. Is not particularly limited. Examples of these adhesives include conventionally used acrylic adhesives, rubber adhesives, and synthetic rubber adhesives.

The thickness of the pressure-sensitive adhesive layer 12 is approximately 3
The thickness is set to about 100 μm, preferably about 10 to 40 μm. The thickness of the pressure-sensitive adhesive layer 12 is appropriately set according to the degree of adhesion of the pressure-sensitive adhesive. However, when the pressure-sensitive adhesive layer 12 is partially formed on the peripheral edge of the back surface of the base material 11 as described below, the pressure-sensitive adhesive layer 12 is formed as thin as possible in order to reduce the gap between the base material 11 and the surface of the vessel 5. Is preferred.

At this time, of course, in order to be in a re-peelable state, the adhesive force of the adhesive is such that the anchoring force with the substrate 11 is greater than the adhesive force with the vessel 5. Is adjusted as follows.

Further, in the protective sheet 10 shown in FIG. 1, an antistatic layer 13 is formed on the surface side of the base material 11,
Antistatic treatment has been applied. The antistatic layer 13 is
It is formed by applying a generally used antistatic agent, and its antistatic property is generally about 10 ¹⁰ Ω / □ or less to the extent that dust does not adhere.

If the antistatic layer 13 is formed on at least one of the substrates 11, the effect can be sufficiently exhibited. When the antistatic layer 13 is processed on one side, the surface on which the adhesive layer 12 is formed (liquid crystal) It may be formed on the module 1 side), that is, on the back side of the protective sheet 10, or may be formed on the non-formation side of the adhesive layer 12, that is, on the front side of the protective sheet 10.
Further, the antistatic layer 13 may be formed on both surfaces of the substrate 11.

Further, as an antistatic treatment, an antistatic agent called a kneading type antistatic agent may be kneaded into the substrate 11. In this case,
The surface resistance is set so that the antistatic effect can be exhibited. By performing the antistatic treatment on the base material 11 as described above, the protective sheet 10 itself can be prevented from being charged, and adhesion of dust and dust can be reduced.

In order to improve the anchoring force between the base material 11 and the pressure-sensitive adhesive layer 12 and the antistatic layer 13, the surface of the base material 11 may be subjected to corona treatment, if necessary. It goes without saying that various types of undercoating and backside processing may be performed.

The protective sheet 10 thus produced
The adhesive layer 12 is attached to the surface of the vessel 5 of the liquid crystal module 1 and is used to prevent damage and dust adhesion during transportation and during assembly of the liquid crystal display device. At this time, it is necessary to attach the protective sheet 10 as flexibly as possible, and it is necessary to take care that the protective sheet 10 does not contact the display surface 6.

As described above, the protective sheet 10 of the present invention is intended to prevent the attached protective sheet 10 from contacting the display surface 6 of the liquid crystal module 1 and has sufficient rigidity for this purpose. A substrate 11 is used. Therefore, there is no need to apply excessive tension to the base material 11 to make the base material 11 taut. For this reason, the pressure-sensitive adhesive layer 12 is
It is sufficient to suppress the movement of the head, and it is not always necessary to provide the entire area corresponding to the surface of the vessel 5, but it may be provided partially in the corresponding area. For example, as shown in FIG. 3, the base material 11 may be provided in a belt shape along two sides in the major axis direction (or the minor axis direction shown by a broken line in FIG. 3), or as shown in FIG. May be provided partially in a region corresponding to the vessel 5, such as a dot-like configuration in a region corresponding to the above (shown by a broken line in FIG. 4). Further, the pressure-sensitive adhesive layer 12 does not need to be formed on the entire surface of the belt, and may be formed in a few stripes.

In some cases, the above-mentioned pressure-sensitive adhesive is applied to the surface of the vessel 5 in advance to form a pressure-sensitive adhesive layer 12, and a base material 11 is adhered on the pressure-sensitive adhesive layer 12.
The display surface 6 may be protected.

[0030]

EXAMPLES Next, various protective sheets according to examples of the present invention were prepared, and the effects of the present invention were confirmed.

Example 1 A cationic surfactant ("Electro Stripper QN", Kao Corporation) was diluted about 100 times with isopropyl alcohol, and the thickness was 118 μm and the width was measured with a bar coater. 202mm rolled polyester sheet ("Lumirror", Toray Industries, Inc.)
Was uniformly coated so that the coating amount after drying was 0.3 g / m ² , and a substrate subjected to an antistatic treatment was obtained.

Next, along the two sides in the major axis direction on the surface opposite to the surface subjected to the antistatic treatment, the following acrylic pressure-sensitive adhesive was dried to a thickness of about 30 μm, and the width of the pressure-sensitive adhesive layer was 4 mm. After being applied with a coating machine, the sheet was cut into a size of 275 mm in length according to the size of the liquid crystal module as an adherend, and a protective sheet of Example 1 was produced.

As the acrylic pressure-sensitive adhesive, a polymer obtained by a usual solution polymerization method (polymer composition weight ratio:
BA / EA / AN / AA = 70/24/3/3 100 parts by weight of an average molecular weight and 100 parts by weight of an epoxy-based cross-linking agent ("Tetrad C", Mitsubishi Gas Chemical Co., Ltd.) are used. Was.

Example 2 A substrate subjected to an antistatic treatment in the same manner as in Example 1 was cut into a size of 275 mm × 202 mm according to the size of a liquid crystal module as an adherend. Next, on a surface opposite to the surface on which the antistatic treatment was performed, a total of 10 hot melt-based pressure-sensitive adhesives described below were placed in a region shown in FIG. About 30μ after drying
m, applied to form a circle having a diameter of about 4 mm.
Was produced.

As a hot-melt adhesive, 55 parts by weight of ethylene-vinyl acetate copolymer ("EV45X", Mitsui DuPont Chemical Co., Ltd.), terpene phenolic resin ("YS Polystar T100", Yasuhara Chemical Co., Ltd.) ) 25 parts by weight, oxidized wax (“OX-WEI”)
SSEN-8 ", manufactured by Nippon Seisaku Co., Ltd.) in an amount of 25 parts by weight.

Example 3 A polymer having a quaternary ammonium group ("Bondip PA-100 main agent (solid content: about 3
0%), 10 parts by weight of Konishi Co., Ltd., and an epoxy-based curing agent (“Bondip PA-100 curing agent (solid content: about 30%)
%), 10 parts by weight of Konishi Co., Ltd., an antistatic agent consisting of 30 parts by weight of water and 30 parts by weight of isopropyl alcohol, and having a corona treatment on one side so that the thickness after drying becomes about 1 μm. A base material which was applied to a corona-treated surface of a roll-shaped polyester sheet ("Lumirror", Toray Industries, Inc.) having a width of 118 μm and a width of 202 mm to obtain an antistatic treatment was obtained.

Next, the same acrylic pressure-sensitive adhesive as in Example 1 was applied to a coating machine so that the thickness after drying was about 30 μm along two sides in the major axis direction on the antistatically treated surface. Then, the sheet was cut into a size having a length of 275 mm according to the size of the liquid crystal module as an adherend, and a protective sheet of Example 3 was produced.

Example 4 An acrylic plate ("Acrylite L", Mitsubishi Rayon Co., Ltd.) having a thickness of 0.5 mm was used.
A protective sheet of Example 4 was produced in the same manner as in Example 1 except that both surfaces were subjected to an antistatic treatment.

(Example 5) 100 parts by weight of a polypropylene resin ("Noblen FL-4", Mitsubishi Chemical Corporation)
After mixing 1 part by weight of a kneading type antistatic agent (“Chemistat 1100”, Sanyo Chemical Co., Ltd.) using a Henschel mixer, using an injection molding machine (nozzle temperature about 230 ° C., mold temperature about 50 ° C.) Thus, a film having a thickness of 1 mm was obtained. Using the film, a circular pressure-sensitive adhesive layer having a diameter of about 4 mm was formed in the same manner as in Example 2 to obtain a protective sheet of Example 5.

Comparative Example 1 A protective sheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that a polyester film having a thickness of 50 μm was used.

(Comparative Example 2) One side of a polyethylene film having a thickness of 50 μm was subjected to a corona treatment, and the treated surface was coated with the same acrylic pressure-sensitive adhesive as in Example 1 to a thickness of 10 μm after drying.
The protective film of Comparative Example 2 was obtained by uniformly coating the entire surface of the film with a coating machine so as to have a thickness of μm.

[Evaluation Test] Next, the following evaluation tests were performed using the protective sheets of the above Examples and Comparative Examples. (Presence or absence of contact between display surface and protective sheet) 12.1 inch TFT liquid crystal module (total size: 202 mm × 275 mm, size of display portion: 189)
(mm × 250 mm), each protective sheet was adhered to the surrounding bezel, and it was visually confirmed whether or not the protective sheet was in contact with the display surface.

(Presence or absence of change in color tone of display section) Each liquid crystal module to which the protective sheet was adhered was subjected to a temperature of 40 ° C. and a relative humidity of 9
After being stored in a 0% oven for 10 days, the backlight was turned on to evaluate whether or not the display had a change in color tone.

(Electrification Property of Protective Sheet) The area of each protective sheet to which the pressure-sensitive adhesive was not applied (however, when the antistatic layer was formed, the non-formed surface side) was treated at a temperature of 23 ° C. and a relative humidity of 60 ° C. % Of the cigarette ash placed on a desk and approached to a position 10 cm above the cigarette ash placed on a desk in an environment of 10%, it was visually confirmed whether or not the cigarette ash adhered to the protective sheet. .

(Electrostatic Resistance to Liquid Crystal Module) Each protective sheet was attached to the liquid crystal module and stored at room temperature for 10 days. Then, at a temperature of 23 ° C. and a relative humidity of 60%, an ungrounded conductive mat was used. The distance from the back to the back was set to 20 mm, and the protective sheet was peeled off so that the pulling speed of the protective sheet became about 10 m / min. The digital electrostatic potential meter (Kasuga Electric Co., Ltd.) , The charged voltage (v) on the surface of the liquid crystal module display was measured.

The evaluation results are shown in Table 1. As can be seen from Table 1, in the protective sheet of each embodiment, there was no contact with the surface of the display section of the display module, and a change in color tone of the display section was observed. Did not. In addition, the non-adhesiveness of dust and the like was excellent, and no charge was observed on the display module. Thus, the effect of the present invention was confirmed.

[0047]

[Table 1]

[0048]

According to the protective sheet for a liquid crystal module of the present invention, the pressure-sensitive adhesive layer comes into contact only with the fixing frame of the liquid crystal module, and the protective sheet does not come into contact with the surface of the display section. There is no charging of the liquid crystal module as the body. Therefore, destruction of the semiconductor device in the liquid crystal module and destruction of the liquid crystal due to separation charging do not occur.

Further, the protective sheet does not contact the surface of the display unit at all, and there is no boundary between the contact area and the non-contact area of the protective sheet on the display unit surface. Therefore, no optical color tone change occurs in the liquid crystal module.

Further, since the pressure-sensitive adhesive layer is provided on the protective sheet in advance, the workability of mounting the liquid crystal module on the liquid crystal module is good.

Further, in the liquid crystal module of the present invention, since the protective sheet of the present invention is mounted, no optical color change occurs.

Further, according to the method for protecting a liquid crystal display portion of a liquid crystal module of the present invention, the display surface of the liquid crystal module can be well protected without causing an optical color tone change.

As described above, according to the present invention, it is possible to prevent adhesion of dust and damage to the surface during transportation and storage without lowering the reliability of the liquid crystal module and thus the liquid crystal display device.

[Brief description of the drawings]

1 is a schematic structural view of a protective sheet for a liquid crystal module according to an embodiment of the present invention, wherein FIG. 1 (a) is a sectional structural view and FIG. 1 (b) is a rear view thereof.

FIG. 2 is a schematic cross-sectional structural view of the liquid crystal module according to one embodiment of the present invention, on which the protective sheet for a liquid crystal module is mounted.

FIG. 3 is a rear view of a liquid crystal module protection sheet according to another embodiment of the present invention.

FIG. 4 is a rear view of a liquid crystal module protection sheet according to still another embodiment of the present invention.

FIG. 5 is a schematic sectional structural view showing an example of a conventional liquid crystal module with a protective sheet attached.

FIG. 6 is a schematic sectional structural view showing another example of a conventional liquid crystal module with a protective sheet attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal module 2 Liquid crystal part 3 Reflector 4 Various optical films 5 Bessel (fixed frame) 10 Protective sheet for liquid crystal modules according to the present invention 11 Base material 12 Adhesive layer 13 Antistatic layer

Claims (5)

[Claims] 1. A protective sheet for a liquid crystal module to be mounted on a liquid crystal module having a fixed frame around a liquid crystal display section, wherein the plastic sheet has rigidity capable of maintaining a non-contact state with the surface of the liquid crystal display section when mounted. A protective sheet for a liquid crystal module, wherein a releasable pressure-sensitive adhesive layer is formed on one surface of a substrate made of a material in a region corresponding to a fixing frame of the liquid crystal module as an adherend. 2. The protective sheet for a liquid crystal module according to claim 1, wherein the plastic substrate has been subjected to an antistatic treatment. 3. A liquid crystal module provided with a fixed frame around a liquid crystal display portion, and a liquid crystal module with a protective sheet provided with the protective sheet for a liquid crystal module according to claim 1 or 2. The liquid crystal module with a protective sheet, wherein the pressure-sensitive adhesive layer is attached to the fixed frame in a state where the base material does not contact the liquid crystal display portion of the liquid crystal module. 4. A method for protecting a liquid crystal display part of a liquid crystal module having a fixed frame around a liquid crystal display part, the plastic having rigidity capable of maintaining a non-contact state with a surface of the liquid crystal display part when mounted. A method for protecting a liquid crystal display portion of a liquid crystal module, wherein the base material is affixed to the surface of the fixed frame using an adhesive while not in contact with the surface of the liquid crystal display portion. 5. The method for protecting a liquid crystal display portion of a liquid crystal module according to claim 4, wherein the adhesive has an anchoring force with respect to the base material greater than an adhesive force with the fixing frame. .