JPH06130223A - Polarizing filter - Google Patents

Abstract

PURPOSE:To provide a polarizing filter having function to clear a linearly polarizable picture together with conditions necessary for interior design and applicable to a window, a shade, a louver, etc. CONSTITUTION:Both sides of a polarizing fabric composed of polarizing fibers 1 having a flat section made of polyvinyl alcohol, an ethylene-vinyl alcohol copolymer, etc., contg. an added dichroic direct dye and nonpolarizing fibers 2 are coated with layers 3 of a flame retardant transparent resin to obtain the objective polarizing filter.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polarizing filter.

[0002]

2. Description of the Related Art Digital video equipment centering on a liquid crystal display device is in the process of development. However, when an image projected on a large-area screen overlaps with external light, it becomes unclear. I have to watch the video. Therefore, while paying attention to the fact that the image light projected from the liquid crystal display device is linearly polarized light, the external light is usually unpolarized light,
A method is devised so that the image can be clearly viewed even in a bright environment by selectively removing only the external light on the screen. For example, there has been proposed a technique for reducing the reflection amount of non-polarizing external light by mounting a light-absorption type polarizing filter oriented in a direction of transmitting linearly polarized image light on the surface of a screen ( See JP-A-62-266980 and JP-A-64-77085). In addition, a technique has been proposed in which a linearly polarized image is sharpened by covering an illumination light source or an illumination window with a light absorption type polarization filter oriented in a direction orthogonal to the polarization filter on the screen (Japanese Patent Laid-Open No. Hei 2). -267536). Conventionally, a general-purpose polarizing filter has been a polyvinyl alcohol (abbreviated as P).
In the stretched film of VA) (thickness: about 20 μm), the rod-shaped aggregate of iodine is oriented in the stretching direction, and then a transparent protective film of triacetyl cellulose (abbreviated as TAC) (thickness: about 80 μm) is formed on both sides of the stretched film.
In the liquid crystal display device, it is used for converting non-polarized light source light into linearly polarized light and forming image light. A polarizing filter in which a dichroic organic dye is oriented in a stretching direction in a stretched film of polyester (abbreviated as PET) is also commercially available, but the fact is that the degree of polarization is lower than that of a PVA / iodine type polarizing filter. .

[0003]

A linearly polarized image projected from a liquid crystal display device can be sharpened by utilizing a polarizing filter in principle. However, an optical product equipped with such a polarizing filter is indoors. Since it is usually used,
In addition to the optical function, the interior quality is required.
Regarding polarizing screens, the forms and base materials cultivated in conventional non-polarizing screens can be diverted, but since there are no examples of polarizing windows, polarizing blinds, polarizing louvers, etc., decorativeness, heat resistance, flame retardancy, processability, strength Issues such as are unsolved.
A PVA / iodine type polarizing filter has a high degree of polarization in the entire wavelength range of visible light, but it is difficult to form a large area due to the restrictions on the stretching technique of the PVA film. Since the protective film is rigid, the flexibility is poor, and it is flammable, so there is a problem as an interior, and because it lacks decorativeness, it is difficult to adapt to the interior.

An object of the present invention is to provide a polarizing filter having both a sharpening function of a linearly polarized image and a necessary condition as an interior.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a polarizing filter of the present invention is a flame-retardant transparent resin made of a polarizing woven fabric having a polarizing flat cross section yarn as a constituent element. It is characterized by being coated with.

The polarizing flat cross section yarn in the present invention comprises PVA to which a dichroic direct dye is added,
For example, a copolymer of ethylene and vinyl alcohol (abbreviated as EVOH) to which a dichroic direct dye is added can be used.

[0007]

The large area of the conventional flat film type polarizing filter is restricted by the limit of the lateral uniaxial stretching technique. However, a polarizing woven fabric in which a polarizing flat cross section yarn and a non-polarizing yarn are crossed is used. When the polarizing filter is manufactured by using the above method, the constraint condition for increasing the area is remarkably relaxed. The polarizing cross-section yarn can be produced by adding a dichroic dye to a transparent polymer, spinning and drawing with a spinneret having a flat opening, or film-forming by a conventional method, longitudinal uniaxial drawing and cutting. Dichroic pigments are roughly classified into direct dyes for hydrophilic polymer films and disperse dyes for hydrophobic polymers,
The former has been put into practical use, such as benzidine, dianisidine, tolidine, and sterbene, and the latter azo and anthraquinone. The polarization degree of the PVA / iodine type polarization filter reaches 99.9% or more, whereas the polarization degree of the polarization filter using the dichroic dye is about 98% or less, but the linear polarization image is sharpened. 90 for the purpose
% Around is enough. The heat-resistant temperature for the degree of polarization of PVA / iodine type polarizing filters is the denaturation temperature (6
On the other hand, the heat resistance temperature for the polarization degree of a polarizing filter using a dichroic dye is about 0 ° C.), and the polymer glass that constitutes the polarizing filter is the discoloration temperature of the dichroic dye (usually 200 ° C. or higher). It is regulated by the lower one of the transition temperatures (usually 200 ° C. or lower), but it is often much higher than the PVA / iodine system.

An example of the polarization filter of the present invention is shown in FIG. In the polarizing filter shown in FIG. 1, a water-soluble dichroic direct dye is added to hydrophilic PVA or EVOH having an intermediate property between hydrophilicity and hydrophobicity to produce a polarizing flat cross-section yarn 1 (A flat cross section yarn made of these materials has a heat resistant temperature of 150 ° C. or higher) and a non-polarizing yarn 2,
Polarized woven fabrics having a geometrical pattern peculiar to woven fabrics include, for example, polyvinyl chloride (abbreviated as PVC) and polycarbonate (abbreviated as P).
It is covered with a transparent and thermoplastic resin layer 3 such as C). Non-polarized light A that has entered the polarization filter passes through the polarization filter and becomes linearly polarized light B.

The polarizing filter according to the present invention has a decorative property based on a geometrical pattern of a woven fabric, flame retardancy exhibited by a coating material, machinability, thermoformability, tensile strength, bending strength,
Since it has excellent properties required for interior optical products such as large area and light weight, it is widely applied to substrates such as polarizing windows, polarizing blinds and polarizing louvers as illustrated in Fig. 2, Fig. 3 and Fig. 4. it can.

[0010]

【Example】

Example 1 PVA whose moisture content was adjusted to 50% by weight (average degree of polymerization: 17
40, saponification degree 99.9 mol% and dichroic direct dyes (Direct Red 81, Direct Green 85 and Direct Blue 1 manufactured by Mitsubishi Kasei Co., Ltd.) at 38:44:18.
0.30% by weight was added, and the mixture was heated in a single-screw extruder to melt, and then a rectangular opening (length 0.10 mm, width 1)
A flat cross section yarn having a thickness of 92 μm, a width of 8.50 μm and a water content of 1.50 wt% was spun using a spinneret having a diameter of 0.0 mm). This flat cross section yarn at 215 ° C.
After stretching by 0 times, the shape is stabilized by shrinking 20% in the longitudinal direction at 220 ° C. to obtain a dry tensile strength of 5.1 g / d, a dry tensile elongation of 12.2%, a thickness of 32 μm, and a width of 6.80 mm. A polarizing flat cross section yarn was prepared. A PVA monofilament having a fineness of 97 denier was obtained by spinning the thus obtained polarizing flat section yarn as a warp and using the same PVA as in the case of the polarizing flat section yarn with a spinneret having a circular opening (diameter 0.40 mm). A polarizing woven fabric having a width of 1.0 m was manufactured as a weft. This polarizing woven fabric was coated with a PVC resin layer having a thickness of 80 μm using a topping machine to prepare a polarizing filter having an average thickness of 280 μm, a width of 1.0 m and a polarization degree of 90%. A sheet 4 made of this polarizing filter was laminated with glass 5 and attached to a window frame 6 to produce a polarizing window as shown in FIG.

Example 2 PVA (average degree of polymerization: 17) adjusted to a moisture content of 45% by weight.
40, saponification degree 99.9 mol% and dichroic direct dyes (Direct Red 81, Direct Green 85 and Direct Blue 1 manufactured by Mitsubishi Kasei Co., Ltd.) at 38:44:18.
Of 0.35% by weight), heated in a twin-screw extruder to melt, and then discharged from a general-purpose film-forming die onto a mirror-finishing roller and dried at 50 to 145 ° C. to a drying roller. To prepare a film having a thickness of 145 μm and a width of 1.0 m. This film was cut into a tape with a width of 10 mm by a slitter, and stretched 5.00 times in the longitudinal direction at 220 ° C.
A method of stabilizing the morphology by shrinking 15% in the longitudinal direction at 225 ° C., a dry tensile strength of 3.8 g / d, a dry tensile elongation of 13.
A polarizing flat cross section yarn having a thickness of 1%, a thickness of 45 μm and a width of 8.00 mm was prepared. The thus obtained polarizing flat cross section yarn was used as a warp, and the transparent non-polarizing flat cross section yarn prepared by omitting the addition of the dichroic direct dye was used as a weft. A polarizing woven fabric of 1.8 m was woven. Using a topping machine, the polarizing woven fabric was covered with a PC resin layer having a thickness of 60 μm, an average thickness of 210 μm, a width of 1.8 m,
A polarizing filter having a polarization degree of 92% was produced. The support frame 8, the hanging cord 9 and the operation cord 10 were attached to the sheet 7 made of this polarizing filter to manufacture a polarizing blind as shown in FIG.

Example 3 EVOH resin (ethylene content 32 mol%, saponification degree of vinyl acetate component 99.6%, load 2.90 kg at 190 ° C.)
Melt index of 1.3 g / min)
30:58:12 of dichroic direct dye (Direct Red 81, Direct Green 85 and Direct Blue 1 manufactured by Mitsubishi Kasei Co., Ltd.) were added to 100 parts by weight of the mesh pass powder.
40% by weight of a 2.50% by weight aqueous solution (mixed in a weight ratio of 1), and sealed so that water does not evaporate, and the mixture is kept at 80 ° C for 24 hours
After heating, open the package and open at 80 ° C for 48 hours, then 105 ° C.
It was dyed by drying for 48 hours. This dyed powder was pelletized at 210 ° C. using a twin-screw extruder, and then a non-stretched film having a thickness of 120 μm was formed at 210 ° C. using a single-screw extruder, and the longitudinal length was 4.00 times at 80 ° C. Axial stretching and 17
A polarizing film having a thickness of 35 μm and a degree of polarization of 85% was produced by a method of stabilizing the shape by heat treatment at 0 ° C. for 5 seconds. A polarizing flat cross-section yarn obtained by cutting the polarizing film into a tape shape having a width of 5.00 mm by a slitter is used as a warp, which is the PVA used in Example 1.
A polarizing woven fabric having a width of 1.4 m was woven using the single fiber as a weft. An adhesive for dry laminating (Takelac A-385 and Takenate A-50, manufactured by Takeda Pharmaceutical Co., Ltd., mixed in a weight ratio of 6: 1) was used as a solid content of 3 g / m ² on both surfaces of this polarizing woven fabric. After coating and evaporation of the solvent, a thickness of 10
By laminating 0 μm hard PVC film, a polarizing filter having an average thickness of 320 μm, a width of 1.4 m and a polarization degree of 85% was produced. A sheet 11 made of this polarizing filter was attached around the illumination lamp 12 to produce a polarizing louver as shown in FIG.

A polarization window 13, a polarization blind 14 and a polarization louver 15 manufactured by using the polarization filter of the present invention are arranged as shown in FIG.
In the environment where the viewer 18 is bright, the direction of vibration of the linearly polarized image light from 6 is made orthogonal and the illumination light is absorbed on the polarizing screen 17 oriented in a direction that does not absorb the image light. You can see clear images.

[0014]

According to the present invention, it is possible to provide a polarizing filter which can be applied to windows, blinds, louvers and the like, and which has a function of sharpening a linearly polarized image and a necessary condition as an interior.

[Brief description of drawings]

FIG. 1 is a perspective view showing a polarization filter according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a polarizing window manufactured by using the polarizing filter of the present invention.

FIG. 3 is a perspective view showing an example of a polarizing blind manufactured using the polarizing filter of the present invention.

FIG. 4 is a perspective view showing an example of a polarization louver produced by using the polarization filter of the present invention.

FIG. 5 is a perspective view showing an example of a polarization space in which a polarization window, a polarization blind, and a polarization louver made by using the polarization filter of the present invention are arranged.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Polarizing flat cross-section yarn 2 ... Non-polarizing yarn 3 ... Flame-retardant transparent resin layer 4, 7, 11 ... Sheet comprising the polarizing filter of the present invention 13 ... Polarizing window 14 ... Polarizing blind 15 ... Polarizing louver 16 ... Projector 17 ... Polarizing screen A ... Non-polarized B ... Linearly polarized light

Claims (1)

[Claims] 1. A polarizing filter in which a polarizing woven fabric having a polarizing flat cross section yarn as a constituent element is coated with a flame-retardant transparent resin.