JPS6140084B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel and useful reflective polarizing plate having coloring ability and reflective ability.

Conventionally, a polarizing plate is made by adsorbing and aligning a polarizing element such as iodine to a film such as a polyvinyl alcohol film, and a surface protection film such as an acetate film is bonded to both sides of the polarizer.

On the other hand, a color liquid crystal display device incorporating this polarizing plate has polarizing plates arranged on both sides of a liquid crystal cell with liquid crystal sealed between two substrates, and a color polarizing plate on the visible side to guide light to the inner side. A reflective light diffusing plate such as aluminum foil is provided through the body.

However, since the light diffusing plate is made of aluminum foil, it is not only easily damaged, but also has the problem of making the entire display device bulky.

The present invention relates to a novel reflective polarizing plate that solves these problems, and its gist is as follows:
A polarizer made by adsorbing and aligning a polarizing element to a film; one side of the polarizer is provided with a surface protective film layer that imparts colored transparency, and the other side is made of a surface that is imparted with light reflecting ability by mixing pearl pigments. A protective film is provided.

As the polarizer, as is generally known, a polarizing element such as iodine or a dichroic dye is adsorbed and aligned on a film such as a polyvinyl alcohol film or a polyvinyl butyral film, and a polyene polarizing film is used.

The surface protection film layer provided on one side of the polarizer is made of (meth)acrylic resin, polycarbonate, acetate, polyester, polystyrene,
It is composed of a polymer material such as polyurethane or a transparent substance such as glass material, which is given colored transparency by adding a coloring agent such as dye or adsorbing it to a film, and the other side is made of a transparent material such as a glass material. For example, basic lead carbonate,
It is made by uniformly dispersing and mixing pearl pigments such as bismuth acid chloride and titanium dioxide-coated mica to create a colored transparent state.

Therefore, as a surface protection film imparted with colored transparency, the average transmittance in the visible light region of 570 to 700 nm is 60% or more, and the average transmittance in the visible light region of 420 to 570 nm is lower than the average transmittance in the visible light region of 570 to 700 nm. Preferably the value when subtracting is 10-50%
It is preferable to set the content to 15 to 35% because a suitable gold-colored reflective polarizing plate can be obtained.

In addition, as a pearl pigment, muscovite, which has excellent colorless transparency, is cleaved and crushed to have an average longest diameter of about 3 to 150μ, and 1/10 or less of the diameter, preferably 1/15 to 1/100.
Titanium dioxide-coated mica is made of scaly mica with a thickness of In use, the mica (pearl pigment) is arranged in a film layer to create a layered structure, and the incident light is regularly and multiple reflected by the arranged scale-like mica, resulting in a soft and deep luster. Therefore, it is preferable.

The amount of pearl pigment added depends on the size, shape,
Although it varies depending on the material, it can be added in a range of about 5 to 50% by weight. If it is less than 5% by weight, the light transmittance is good, but the reflection and diffusion effects are insufficient, and if it is more than 50% by weight, the diffusion effect is insufficient and the transmittance is reduced, which is not preferable.

To integrate each protective film layer with a polarizer, a mixture of dyes or pearl pigments uniformly dispersed in a transparent material is formed into a film (about 15 to 100μ thick) in advance, and then attached to the polarizer. Alternatively, a transparent substance with a composition that can be applied and cured by a polymerization reaction is selected, and a dye or pearl pigment is uniformly dispersed and mixed therein, and the coating is applied to the polarizer surface and dried. It's okay.

When the reflective polarizing plate of the present invention is used in a color liquid crystal display device using a light emitter, the color polarizing plate, reflective light diffuser plate, light guide, and surface protection film on one side (the side where the conventional reflective plate is installed) are omitted. Therefore, the display device as a whole does not become bulky and has the feature that it can be made smaller and lighter. Moreover, the protective film layer imparted with light reflecting ability is less susceptible to scratches than aluminum, so the product yield is significantly improved.

Claims (1)

[Claims] 1. A polarizer made by adsorbing and aligning a polarizing element to a film. One side of the polarizer is provided with a surface protection film layer that gives it colored transparency, and the other side is given a light reflecting ability by mixing a pearl pigment. A reflective polarizer with a protective film layer.