JPH0968613A - Reflection type polarizing plate and production of liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance reflectivity and to make display of characters, etc., visible as brightly as possible by forming silver by vapor deposition at a thickness of a specific value or above on the matted surface of a reflection material. SOLUTION: A liquid crystal cell 1 is formed by holding the cell with a polarizing plate 2 and a polarizing plate 3 with the reflection material 4. A polyester film 4a subjected to matting is adopted for the reflection material 4 of the polarizing plate 3 with the reflection material 4. The silver 4b is deposited by evaporation at a thickness of >=1300 angstrom on the matted surface of the polyester film 4a. The durability may be improved while the excellent optical characteristic of enhancing the reflectivity is maintained if the thickness of the vapor deposited layer of the silver 4b is set at >=1300 angstrom. As a result, the reflection type polarizing plate and liquid crystal display with which the display of characters, etc., is more distinctly visible and which have the extremely outstanding durability are obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflective polarizing plate and a method for manufacturing a liquid crystal display, which enables brighter visual recognition of characters and the like.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal cell 1 is sandwiched between a polarizing plate 2 (transmissive polarizing plate) and a polarizing plate 3 with a reflecting material 4 (reflective polarizing plate). Various types of liquid crystal displays have been proposed (the same components as those in this embodiment are designated by the same reference numerals).

A polarizing film 3 with a reflecting material 4 used in such a reflection type liquid crystal display body is generally formed by laminating an aluminum foil on a polyester film as the reflecting material 4.
Alternatively, a matte-processed polyester film with aluminum vapor-deposited is used.

By the way, in order to make the display of characters and the like visible more brightly, it is indispensable to increase the reflectance of the reflecting material and effectively use the outside light.

The present invention provides a reflection type polarizing plate and a method for manufacturing a liquid crystal display, which enhances the reflectance by adopting a reflecting material having a predetermined structure, thereby making it possible to visually recognize characters and the like as brightly as possible. To do.

[0006]

The gist of the present invention will be described with reference to the accompanying drawings.

A reflective polarizing plate comprising a polarizing plate 3 laminated on the matte surface of a reflective material 4 having a surface matte processed,
The present invention relates to a reflective polarizing plate characterized in that silver 4b having a thickness of 1300 angstrom or more is vapor-deposited and formed on a matte surface of a reflective material 4.

The reflective polarizing plate according to claim 1 is characterized in that a polyester film 4a is adopted as the reflecting material 4.

A reflection type polarizing plate in which a polarizing plate 3 is laminated on the matte surface of a reflecting material 4 having a surface matte treatment, wherein an undercoat 4c of acrylic resin is provided on the matte surface of the reflecting material 4. The present invention relates to a reflection type polarizing plate characterized in that a vapor deposition layer of silver 4b having a thickness of 1300 Å or more and a top coat 4d made of an acrylic resin are laminated in this order.

A method of manufacturing a liquid crystal display body, in which a liquid crystal cell 1 is sandwiched between a polarizing plate 2 and a polarizing plate 3 with a reflecting material 4, wherein the reflecting material 4 of the polarizing plate 3 with the reflecting material 4 is used. As
The present invention relates to a method for producing a liquid crystal display, characterized in that a matte-processed polyester film 4a is adopted and silver 4b is vapor-deposited on the matte surface of the polyester film 4a in a thickness of 1300 Å or more.

A method of manufacturing a liquid crystal display body, in which a liquid crystal cell 1 is sandwiched between a polarizing plate 2 and a polarizing plate 3 with a reflecting material 4, wherein the reflecting material 4 of the polarizing plate 3 with the reflecting material 4 is used. As
A matte-processed polyester film 4a is adopted, an undercoat 4c is applied to the matte surface of the polyester film 4a by an acrylic resin, and subsequently, a silver 4b having a thickness of 130 is formed on the undercoat 4c.
The present invention relates to a method for producing a liquid crystal display, characterized in that vapor deposition is performed at 0 angstrom or more, and then a top coat 4d is applied to the silver vapor deposition surface with an acrylic resin.

Further, in the method for manufacturing a liquid crystal display according to claim 5, the acrylic resin undercoat 4c is used.
And a top coat 4d having a thickness of 1 to 2 μm.

[0013]

The function and effect of the present invention, the present inventors have already filed Japanese Patent Application No. 7-193487 "reflective type polarizing plate and a method for producing a liquid crystal display", the matte processing of the reflective material 4 surface matte When silver 4b is vapor-deposited on the surface, an undercoat 4c made of an acrylic resin, a vapor-deposited layer of silver 4b, and a top coat 4d made of an acrylic resin are laminated in this order on the matte surface of the reflective material 4 having a matte surface. Then, it has been confirmed by an experiment that the reflectance of the reflector 4 is increased.

According to the present invention, on the basis of the above experimental results, based on various comparison data based on 1300 angstrom as the thickness of the vapor-deposited layer of silver 4b, the thickness of the vapor-deposited layer of silver 4b is 1300 angstroms or more. if you did this,
It has been confirmed that durability can be improved while maintaining excellent optical characteristics such as increased reflectance, and it is summarized as a claim.

As described above, the present invention provides a method of manufacturing a reflective polarizing plate and a liquid crystal display, which enables the display of characters and the like to be seen brighter and has extremely excellent durability. You will get it.

[0016]

EXAMPLE A first example will be described (see FIG. 1).

Polyester film 4a having a thickness of 50 μm
Is matted (kneading type) on its surface, and silver 4b is vapor-deposited (vacuum vapor deposition) with a thickness of 1300 angstroms on the matte surface.

The polyester film 4a was directly coated with the pressure-sensitive adhesive 5 (acrylic) on the silver-deposited surface with a thickness of 15 to 20 μm, and dried, and then the known polarizing plate 3 (PVA film was TAC
The polarizing plate 3) held by the film is attached.

Subsequently, the liquid crystal cell 1 is formed on the upper surface of the polarizing plate 3.
Are bonded via an adhesive 5 (acrylic), and the polarizing plate 2 having the same structure as the above is bonded via an adhesive 5 (acrylic) to obtain a liquid crystal display.

A second embodiment will be described (see FIG. 2).

Polyester film 4a having a thickness of 50 μm
Matte surface (kneading type) is applied to the surface, and the matte surface is undercoated with acrylic resin undercoat 4c having a thickness of 1 to 2 μm. Then, a top coat 4d having a thickness of 1 to 2 μm is applied to the silver vapor deposition surface with an acrylic resin. Since the vapor-deposited layer of silver 4b is sandwiched and protected by the undercoat 4c and the topcoat 4d, corrosion of the silver 4b is prevented.

The top coat surface of the polyester film 4a is directly coated with the adhesive 5 (acrylic) having a thickness of 15 to 20.
After coating and drying with a thickness of μm, a known polarizing plate 3 (a polarizing plate 3 in which a PVA film is sandwiched with a TAC film) is attached.

Then, the liquid crystal cell 1 is formed on the upper surface of the polarizing plate 3.
Are bonded via an adhesive 5 (acrylic), and the polarizing plate 2 having the same structure as the above is bonded via an adhesive 5 (acrylic) to obtain a liquid crystal display.

The vapor deposition layer of silver 4b is controlled by adjusting the processing speed during vacuum deposition, the degree of vacuum, the temperature of the melting crucible of silver, and the like.

Table 1 shows the evaluation results of the optical characteristics of this embodiment. The reflective material 4 according to the second embodiment is used as the reflective material 4, and four types of reflective materials 4 having different silver vapor deposition thicknesses are used.
Was prepared, and the reflectance and hue of each of them were evaluated.

[0026]

[Table 1]

It can be confirmed from Table 1 that the four types are almost equal and excellent in terms of reflectance and brightness L and hues a and b.

Table 2 shows that the above-mentioned four types of reflecting materials 4 are integrated with the polarizing plate 3 (reflective type polarizing plate), and the temperature is 40 ° C.
95% RH x 250 Hr, 70 ° C-dry x 250 Hr
The durability is evaluated.

40 ° C. × 90% RH × 250 Hr is
The condition was that it was left for 250 hours in an atmosphere of 40 ° C. and 95% relative humidity, and 70 ° C.-dry × 250.
Hr is a condition of being left for 250 hours in a dry atmosphere at 70 ° C.

[0030]

[Table 2]

From Table 2, the deposition thickness of silver 4b is 1
It can be confirmed that the durability is excellent when the thickness is 300 angstroms or more.

As described above, according to the experimental results shown in Tables 1 and 2, the reflective material 4 maintains excellent optical characteristics even if the vapor deposition thickness of silver 4b is 1300 angstroms or more.
It can be confirmed that corrosion resistance and durability are excellent when the thickness is 00 angstroms or more.

Regarding the upper limit of the vapor deposition thickness of silver 4b with respect to durability, the thicker the vapor deposition thickness is, the more the durability is not improved. I presume. On the other hand, if the vapor deposition thickness is increased, problems such as an increase in cost and a tendency for cracks to occur in the vapor deposition layer when bent will occur. Therefore, the upper limit of the deposition thickness of silver 4b is estimated to be about 1600 angstroms.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first embodiment.

FIG. 2 is an explanatory diagram of a second embodiment.

[Explanation of symbols]

 1 Liquid Crystal Cell 2 Polarizing Plate 3 Polarizing Plate 4 Reflecting Material 4a Polyester Film 4b Silver 4c Undercoat 4d Topcoat

Claims (6)

[Claims] 1. A reflection type polarizing plate comprising a polarizing plate laminated on the matte surface of a reflective material having a surface matte processed, wherein silver is vapor-deposited and formed on the matte surface of the reflective material in a thickness of 1300 Å or more. A reflective polarizing plate characterized by the above. 2. The reflective polarizing plate according to claim 1,
A reflective polarizing plate characterized by using a polyester film as a reflective material. 3. A reflection type polarizing plate comprising a reflective material having a surface matte processed and a polarizing plate laminated on the matte surface, wherein the matte surface of the reflective material is undercoated with an acrylic resin and has a thickness of 1300 angstroms. A reflective polarizing plate comprising the above vapor-deposited silver layer and a top coat of acrylic resin laminated in this order. 4. A method of manufacturing a liquid crystal display body, comprising a liquid crystal cell sandwiched between a polarizing plate and a polarizing plate with a reflecting material, wherein matting is applied as the reflecting material of the polarizing plate with the reflecting material. A method for producing a liquid crystal display, which comprises using a polyester film and depositing silver on the matte surface of the polyester film in a thickness of 1300 Å or more. 5. A method of manufacturing a liquid crystal display body, comprising a liquid crystal cell sandwiched between a polarizing plate and a polarizing plate with a reflecting material, wherein matting is applied as the reflecting material of the polarizing plate with the reflecting material. A polyester film is used, and the matte surface of this polyester film is undercoated with an acrylic resin. Then, silver is vapor-deposited on the undercoat surface to a thickness of 1300 angstroms or more. A method for producing a liquid crystal display, comprising: applying a top coat of acrylic resin on the above. 6. The method for producing a liquid crystal display according to claim 5, wherein the undercoat and the top coat made of an acrylic resin have a thickness of 1 to 2 μm.