JPS59151112A - Polarizing plate - Google Patents

Abstract

PURPOSE:To improve durability, heat stability, and scratch resistance by forming a hardened film made from a UV hardenable polyester acrylate type resin compsn. contg. silica sol on the surface of an unstretched or monoaxially stretched plastic layer. CONSTITUTION:A hardened film layer 3 is formed using a compsn. of a UV hardenable polyester acrylate type resin contg. silica sol on the surface of a plastic layer 2 of a polarizing material formed by coating the surface of a polarizing film 1 with an unstretched or monoaxially stretched plastic film 2. Such a polarizing plate is given superior durability and heat stability by forming the film 3 of the polyester acrylate resin, and good scratch resistance by the high hardness of the film 3, and scratches are prevented in using it for a large- sized polarizing plate of a motorcar meter or the like during the manufacturing process and in the practical application stages.

Description

[Detailed description of the invention]
Excellent<11if) Y: 1 da 1 on the board.

The polarizing plate is generally made by cutting a transparent plastic FI'I on the surface of a lightning film (σ), and its alter egos are also used for conventional calculators, time h1-, etc. As a small power distribution unit, a meter for own #-1ff, and an instrument.
) is being expanded to larger items.

With the expansion of this field of use, polarizing plates [Star-End Sa
Properties such as durability and thermal stability are also desired to be more controlled.

On the other hand, as polarizing plates become more important, scratch resistance on one side of the polarizing plate itself is desired. This occurs during the manufacturing and mounting of polarizing plates.
1 Ino 1ii Kougen board surface r If scratches occur, product circumstances will become apparent 1
．． <This is to prevent the appearance and optical characteristics of the display device from decreasing as well.

The polarizing plate was developed in response to such a request, and its gist is to form a plastic layer on the surface of the polarizing film, either unstretched or stretched in one direction/7). Polarizing base material σ) A cured film layer of I-1, which is a composition containing silica solke in an ultraviolet curable polyester acrylate resin, is formed on the surface of the plastic layer.

Misfire f+7) According to the polarizing plate, a cured film layer made of a composition containing ultraviolet light, jil, and curable polyester acrylate resin M silica sol is formed on the polarizing base material/7) Glasstic F41tri, so that the surface It is characterized by high hardness and excellent scratch resistance, as well as good durability and stability.

The ultraviolet curable polyester acrylate resin used in the present invention generally comprises a polyester polyol and an acrylate or methacrylate monomer having a hydroxyl group such as 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate. It has been discovered that by using such a resin, the composition can be cured by ultraviolet rays, and a cured film layer with high surface hardness and excellent single-shot scratch properties can be obtained. Ta.

The silica sol used in the present invention is amorphous, porous, and colloidally dispersed. Particle size and L7 are 30 mμ or less, preferably average particle size 5 to 25
mμ, its phase refractive index is about 1.46, and its apparent specific gravity is about (1,836).

The ratio of ultraviolet-curable polyester acrylate resin and silica sol is 9 parts by weight of all + 0 to 9 parts by weight, and it is desirable to mix the silica sol in an amount of 1.1 to 35 parts by weight. If the amount of silica sol is less than 0.1 parts by weight, the surface hardness of the cured film layer will be low, and if it is more than 35 parts by weight, the optical properties will be deteriorated, which is not preferable.

In addition to crosslinking components such as polyisocyanate compounds, the composition of UV-curable polyester acrylate resin and silica sol contains ethyl (meth)acrylate, isopropyl ( meth)acrylate, alkyl(meth)acrylates such as butyl(meth)acrylate, styrene, (
Seven polymers such as vinyl ester monomers such as meth)acrylonitrile and vinyl acetate, and functional monomers such as (meth)acrylate and glycidyl methacrylate can be added, and the range is 1 to 40M at most. .

Further, additives such as dyes, pigments, and antistatic agents may be added to the composition, and a photopolymerization initiator for the resin may be added.

The initiator and 1. Examples of photosensitizers include those selected from the group such as acetophenone, benzophenone, Michlagton, benzyl, and benzoin.
An imidazole compound, peroxide, etc. can also be used in combination with a raw material compound or the like as a thermally exclusive initiator.

The composition blended in this manner may be added to an organic bath agent which is inert to the positive layer described below, either alone or by coating and curing the composition, so that the solid content concentration is 20 to 951 M%.
It was coated on a cloth plate, coated with a general coating method such as a spinner coater, gravure coater, reverse coater, spray coater, or slot orifice coater to a coating density of 1 to 30)/m (+d type), and after drying, it was cured by ultraviolet rays. It is something that

The polarizing substrate on which a cured film layer made of such a composition is formed is a plastic layer formed on both sides or one side of a polarizing film by means such as coating or bonding, without stretching or stretching only in one direction. It consists of

Therefore, the polarizing plate of the present invention includes, for example, those having the shapes shown in FIGS. 1 to 3.

In FIG. 1, 1 is a polarizing film, 2 is a plastic layer, and 3 is a cured film layer made of the above composition.

In FIG. 2, 1(a) 2.2 and 3.3 are formed on both sides of the film 1, respectively.

ffJ3 The figure shows a polarizing plate and a plastic liquid crystal cell substrate. When used in σ) This is an example in which a patterned transparent electroconductive film 4 is formed on the surface of a layer 3 made of a cured film, and the layer 3 prevents the film 4 from being disconnected due to scratches or the like.

The polarizing film may be a hydrophilic polymer film such as a polyvinyl alcohol film, a partially formalized vinyl alcohol film, or a saponified ethylene-vinyl acetate copolymer film, on which iodine and/or dichroic dyes are adsorbed. Turn [.

iodine and/or dichroic dye-based polarizing film, polyene-based polarizing film in which polyene is distributed by dehydrating a polyvinyl alcohol film or treating a polyvinyl chloride film at a desalting facility. These are usually used having a thickness of 10 to 80 μm.

A plastic layer (I+'1
-The length is approximately 1 +1~201t (1μm is &l"tL)
Polyacrylic thread 1 resin, polyurethane resin can be coated and cured, or polyester resin film, polycarbonate film, polysulfone film, polyether film, trimethylpentene film, polyetherketone film, ) Polyester yarn adhesive, polyacrylic adhesive, plastic film made by unstretched or unidirectionally stretched acrylonitrile film with excellent optical transparency.
It is constructed by bonding with an adhesive that has high optical transparency such as a polyurethane adhesive or a polyvinyl acetate adhesive, or by bonding means such as welding. However, if the plastic layer is desired to have strong chemical properties, it should be at least 5 inches, preferably 50 degrees, only in the vertical or horizontal axis direction.
A polyester film which is stretched at a temperature of 1-110° C. to 230° C. for 5 to 60 minutes is preferable.

In a tlIil optical base made of such a polarizing film and a plastic layer, the surface of the plastic layer on which the composition is applied and cured is treated with alkali treatment, corona treatment, etc. Performing surface treatment such as processing, sputtering, coating of silane coupling agent, or surface modification treatment such as Si vapor deposition, etc.
This is preferred from the viewpoint of improving adhesion between the plastic layer and the cured film layer consisting of the composition/7).

The first polarizing plate obtained in this way has good scratch resistance due to the high hardness of the cured film layer.1-1 Also, the film is made of polyester acrylate resin/7) and is durable. It has the characteristics of quick response to properties and thermal stability.

Below is an example of misfire 1 ladle θ).

Example: A film with a thickness of 1 (
) Adhesion of a 0 μm uniaxially stretched polyester film (low elongation rate 300%) using a polyester adhesive 1. I made a polarizing substrate.

One film of this substrate was coated with composition 4 shown in Table 1.
- Coated with a spinner coater at a line speed of 102 n/min (after drying at 111°C for 3 minutes, ozone type high 14 mercury lamp (80 W/an, 15 ah condensing type)
Ultraviolet irradiation was performed using two lamps to obtain a polarizing plate having a cured 11J layer with an average coating thickness of 4 μmg.

The surface hardness of the coating layer surface of each bucket board is JISKs 40.
] 8U・Identification f-1-j Measured by handwriting trial training l
As a result, the film-forming (7) surface hardness of the reference example was H, whereas each of the non-executive examples had a hardness of 2 to 4 H17').

Table 1 shows all Vrc compositions (unit squirt parts) and measurement results. What are the light transmittance and degree of polarization in Table 1? Measured by J method.

Table 1 (Note) 1) Tumacoat TP-2:32 manufactured by Somar Kogyo Co., Ltd.
2) Coronate HL manufactured by Nippon Borikretan Co., Ltd. 3) Manufactured by Yuuzou Kasei Kogyo Co., Ltd. 17) O8CAP-3102, particle size distribution 1O
~20mμ 4) Manufactured by Ciba Geigy (7) Irgakia-184

[Brief explanation of drawings]

Figures 1 to 3 are partially enlarged side views showing examples of polarizing plates for non-explosion. 3...Cured film j1-1 Patent origin: Hijikata Sanbe, Representative of Hitoichito City Industrial Co., Ltd.

Claims (1)

[Claims] A polarizing group formed by forming a positive layer consisting of a surface film stretching or one direction/7) of a 11ni optical film. 1. A polarizing plate comprising: a set 11 containing silica sol; and a hardened film layer 1- formed thereon.