JPH10197957A - Reflection type screen for projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflection type screen whose angle of visibility is large, and which is especially suitable for the projection of a personal computer image. SOLUTION: A light diffusing and reflecting layer including non-leafing type scaly aluminum paste 10 to 80 pts.wt. as light reflection agent to a binder resin 100 pts.wt. and light diffusing agent of >=50wt.% to the light reflection agent is provided on a base material. Transparent resin beads whose average particle diameter is 2 to 25μm are preferably used as the light diffusion agent. Comparatively large amount of light diffusion agent is included, so that a practical SG(screen gain) value and a contrast ratio can be obtained; therefore, the reflection type screen in which the enlargement of the angle of visibility and the improvement of a horizontal(peripheral) light quantity ratio are attained can be obtained. As to this reflection type screen; a character is displayed as a dark part, and such still image as the image of the personal computer whose white part is large can be clearly reflected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection type screen for a projector for projecting an image projected from a projector such as an OHP, a slide, a projector and the like as reflected light, and more particularly to a still image such as a personal computer (hereinafter referred to as a personal computer) image. The present invention relates to a reflective screen for a projector, which is suitable for projection of a projector.

[0002]

2. Description of the Related Art Conventionally, as a reflection type screen, a two-layer reflection type screen having a reflection layer for reflecting light from a projector and a light diffusion layer for diffusing reflected light is known. . In such a two-layer reflective screen, the reflective layer is made of an aluminum vapor-deposited layer or an aluminum paste-coated layer, and the light reflected by this reflective layer is further diffused by a light diffusion layer to provide a relatively wide viewing angle. You can see images without glare. However, since the reflected light is diffused by the light diffusion layer, the SG (screen gain) value is generally low, and there is a problem that the contrast is reduced due to the influence of external light, particularly when used for viewing in a bright room.

On the other hand, there has been proposed a technique in which a paste in which non-leafing type aluminum scales and pearl pigment scales are mixed is used for the reflective layer in order to improve the reflection luminance (Japanese Patent Application Laid-Open No. 3-119334). However, in such a reflection type screen, when the light diffusion layer is not provided on the reflection layer, the gloss of the screen surface becomes large and the problem of glare remains.

On the other hand, with the recent development of the liquid crystal projector side, a projector having an extremely bright light source and a large difference from external light has been manufactured. When such a projector is used, a reflective film is required. , SG values, that is, superior in the horizontal light amount and the peripheral light amount. In particular, with the increase in size of the screen, a screen capable of viewing a bright image at a wide angle is required. For this reason, a reflective screen (JP-A-6-14846) in which a reflective layer in which a light diffusing agent having a low refractive index is dispersed is formed on a support,
A projection screen in which a diffusing agent such as mica powder or silicon oxide powder and a thixotropic agent for preventing sedimentation of the glittering pigment are added to a reflective layer containing the glittering pigment (Japanese Patent Laid-Open No. 8-231904).
Has been proposed.

[0005]

However, the above-mentioned conventional screen is designed so that a light-irradiated portion (bright portion) has a high contrast with respect to a dark portion as a background. Suitable for moving images,
In a still image in which characters are displayed as dark portions and there are many white backgrounds (bright portions) like a personal computer image, it is necessary that the dark portions be clearly displayed over the entire screen. Also, with the recent increase in the size of reflective screens, screens with particularly excellent horizontal and peripheral light amounts are required. However, conventional screens have sufficient horizontal and peripheral light amounts for large screens such as 60 inches and 80 inches. Has not been realized.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a reflection type screen capable of improving a horizontal light amount ratio and a peripheral light amount ratio, and particularly capable of clearly displaying a still image such as a personal computer image.

[0007]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies on the material constituting the reflective layer and found that the reflective layer containing the light reflective agent contained a light diffuser, By setting the content of the light diffusing agent to 50% by weight or more with respect to the light reflecting agent, even one layer exhibits a reflection characteristic close to the case where two layers of the reflecting layer and the light diffusing layer are formed, and has a horizontal light amount ratio. Also, it has been found that a screen having a high peripheral light amount ratio and particularly suitable for projecting a still image can be obtained.

That is, the reflection type screen for a projector according to the present invention is a reflection type screen for a projector comprising a base material provided with a light diffusion reflection layer containing a binder resin, a light reflection agent and a light diffusion agent. Light reflecting agent 10
More than 50 parts by weight per 0 parts by weight. As the light diffusing agent, transparent resin particles having a particle size of 2 to 25 μm are preferably used. As the light reflecting agent, a non-leafing type flaky aluminum paste is used, and its content is preferably 10 to 80 parts by weight based on 100 parts by weight of the binder resin.

The reflective screen can display a brighter image than a screen provided with a separate light diffusing layer, and can obtain good light diffusing properties without providing a separate light diffusing layer, and can provide uneven brightness. You can see the video without any. Further, since the horizontal light amount ratio and the peripheral light amount ratio can be greatly improved while maintaining practical luminance, the size of the screen can be increased.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a reflective screen for a projector according to the present invention will be described in detail.

As shown in FIG. 1, the reflection type screen for a projector according to the present invention comprises a substrate 1 and a light diffusive reflection layer 2 formed on the substrate 1 as shown in FIG.

As the substrate 1, a resin sheet of a homo- or copolymer of a (meth) acrylate such as methyl methacrylate or methyl acrylate, a polyester such as polyethylene terephthalate, a polycarbonate, a polyvinyl chloride, a polystyrene or the like is used. be able to. Such a substrate 1 may be transparent, but it is preferable to use a material in which a white pigment is kneaded in order to enhance the reflection characteristics of the light-diffusing reflective layer 2. Further, for the purpose of blocking external light, it is preferable to provide a light blocking layer 3 on the side opposite to the light diffusive reflection layer 2 as shown in FIG. The light-blocking layer 3 may be a black film in which a black pigment such as carbon black is appropriately contained in a resin, a paper colored black, or the like. The light-blocking layer 3 is coated on the surface of the substrate 1 opposite to the light-diffusing reflective layer 2. Alternatively, it can be formed by laminating.

The light-diffusing reflective layer 2 comprises a binder resin,
It includes a light reflecting agent 2b and a light diffusing agent 2a. As the binder resin, vinyl acetate resin, modified vinyl acetate resin, modified vinyl acetate / acrylic copolymer resin, ethylene / vinyl acetate resin, polyester resin, acrylic copolymer resin, acrylic silicone resin, cellulose resin, vinyl chloride / vinyl acetate One or two selected from copolymer resins, styrene resins, urethane resins, epoxy resins, modified polyvinyl alcohol resins, acrylonitrile rubber, and the like.
A mixture of more than one species can be used.

As the light reflecting agent, a flaky aluminum paste can be used, and a nonleafing type flaky aluminum paste is particularly preferable. Non-leafing type aluminum paste is made by coating aluminum flakes with oleic acid.When dispersed in a binder resin, the aluminum flakes are properly dispersed without floating on the surface. When incorporated, good light reflectivity can be imparted without impairing the function of the light dispersant. As the aluminum paste, not only one composed of aluminum flakes coated with oleic acid and an organic solvent but also one further containing a resin can be used.

The scaly aluminum paste has an average particle size of the scaly aluminum of 4 to 60 μm, preferably 10 to 40 μm.
Use the one in the range of m. If the particle size of the flaky aluminum is too small, sufficient reflectivity cannot be obtained, and the luminance will be low. If the particle size is too large, glare will be noticeable.

The content of the light reflecting agent is determined by the binder resin 10
The range is preferably 10 to 80 parts by weight, more preferably 30 to 60 parts by weight, based on 0 parts by weight. By setting the amount of the light reflecting agent in such a range, it is possible to obtain sufficient luminance without causing glare.
Here, when the content of the light reflecting agent is an aluminum paste containing a resin in the aluminum paste,
It refers to the content of aluminum solids excluding such resins.

As the light diffusing agent, transparent resin beads are preferred, and those having a spherical shape are particularly preferred. Mica,
An appropriate amount of inorganic particles such as pearl pigments can also be used by mixing with resin beads. By using transparent resin beads, appropriate light diffusing properties can be imparted without impairing the reflection characteristics of the light reflecting agent. As such resin beads, resin beads such as acrylic beads, styrene beads, and urethane beads can be used, and styrene beads are particularly preferable. Resin beads have a particle size of 2 to 25 μm
Are preferred. By using the transparent resin beads having a particle size in such a range, a wide viewing angle and a high SG value can be obtained.

The content of the light diffusing agent is at least 50 parts by weight, preferably at least 70 parts by weight, based on 100 parts by weight of the light reflecting agent. The upper limit of the content of the light diffusing agent is not particularly limited,
The amount is preferably less than 500 parts by weight from the viewpoints of adhesion to the support and physical strength of the layer.

The light-diffusing reflective layer of the present invention may be made of a black color such as carbon black in order to enhance the contrast between a light-irradiated portion (bright portion) and a dark portion, in addition to the above-mentioned light reflecting agent and light diffusing agent. Although a slight amount of a colorant can be contained, the content of the colorant is, for example, 4 parts by weight with respect to 100 parts by weight of the binder resin in the case of carbon black for the purpose of the present invention of clearly displaying a still image. The content is preferably as follows, more preferably 0.5 to 4.0 parts by weight.

Further, the light-diffusing reflection layer of the present invention can contain known additives such as an ultraviolet absorber and an antistatic agent.

The reflection type screen of the present invention is formed by applying the above-mentioned binder resin, light reflecting agent, light diffusing agent and, if necessary, a black colorant and an additive together with a suitable solvent onto a substrate and drying it. it can. The thickness of the light-diffusing reflective layer is not particularly limited, but is usually about 6 to 20 μm. When a light-blocking layer is provided on the substrate, the binder resin and the black colorant forming the light-blocking layer may be formed by coating and drying on a substrate together with a suitable solvent,
Laminate a black film or paper on the side opposite to the light diffusing reflective layer.

The reflection type screen of the present invention having such a configuration is excellent in the ratio of the amount of light in the horizontal direction to the ratio of the amount of light in the periphery, has a wide viewing angle, and can clearly display a still image having a particularly large white background in a wide range.

[0023]

Embodiments of the present invention will be described below. Example 1 100 μm-thick polyester film (Lumirror E2
0: Toray Industries, Inc.), a coating liquid for a light-diffusing reflective layer having the following formulation was applied by a bar coater and dried to form a reflective layer, and a reflective screen was obtained.

Acrylic resin (resin solid content 50%) 30 parts by weight (Acrydic A-807: Dainippon Ink and Chemicals, Inc.) Hardener (solid content 60%) 6 parts by weight (Takenate D110N: Takeda Pharmaceutical Company Limited) Leafing type scaly aluminum paste (50% aluminum solid content) 16 parts by weight (5501EA: Showa Aluminum Powder Co.) Styrene beads (6 μm) 8 parts by weight (SBX-6: Sekisui Chemical Co., Ltd.) Carbon black 0.4 parts by weight acetic acid 40 parts by weight of ethyl 40 parts by weight of butyl acetate

The SG value, contrast ratio, viewing angle, horizontal light amount ratio and peripheral light amount ratio of this reflective screen were measured. The SG value is calculated from the brightness of the screen surface and the illuminance of the light source by the formula SG = (B / E) × π (where B is the brightness of the screen surface (cd / m ² = nit), and E is the illuminance (lm / m). ² = lux)). The contrast ratio is: contrast ratio = (external light reflection luminance + white signal luminance) / (external light reflection luminance +
(Black signal luminance). The viewing angle was measured by changing the angle of the screen surface every 10 ° from 0 ° to 50 ° with the luminance meter fixed, and the luminance at an angle when the front (0 °) luminance was set to 100 was determined. .

As shown in FIG. 3, the horizontal light amount ratio and the peripheral light amount ratio are 10 mm from the edge of the 60-inch screen.
Luminance at 6 points inside% (B1, B2, B3, B5, B6, B7)
And measure the brightness (B4) of one point at the center of the screen,
The following formula: Horizontal light ratio = [{(B2 + B6) / 2} / B4] x 100 Peripheral light ratio = [{(B1 + B3 + B5 + B7) / 4} / B
4] × 100. Table 1 shows the results of the SG value, the contrast ratio, the horizontal light amount ratio, and the peripheral light amount ratio. Table 2 shows the viewing angle results.

Examples 2 to 5, Comparative Example 1 A reflective screen was produced in the same manner as in Example 1 except that the content of styrene beads as a light diffusing agent was changed as shown in Table 1. For these reflective screens, the SG value, the contrast ratio, the viewing angle, the horizontal light amount ratio and the peripheral light amount ratio were measured in the same manner as in Example 1. The results are shown in Tables 1 and 2.

Comparative Examples 2 and 3 Pearl pigment (Iriodin 111: Merck Japan Ltd., Comparative Example 2) and silicon dioxide (Sylysia 770: Fuji Silysia Chemical Ltd., Comparative Example 3) were used as light diffusing agents instead of styrene beads. Otherwise, a reflective screen was manufactured in the same manner as in Example 1. The SG value, contrast ratio, viewing angle, horizontal light amount ratio, and peripheral light amount ratio of these reflective screens were measured in the same manner as in Example 1. The results are shown in Tables 1 and 2.

Comparative Example 4 A reflective screen was produced in the same manner as in Example 1 except that a pearl pigment (Iliodin 111: Merck Japan) was used instead of the aluminum paste as the light reflector. For these reflective screens, the SG value, the contrast ratio, the viewing angle, the horizontal light amount ratio and the peripheral light amount ratio were measured in the same manner as in Example 1. The results are shown in Tables 1 and 2.

[0030]

[Table 1]

[0031]

[Table 2]

As can be seen from the results of Tables 1 and 2, in the reflective screens of the examples in which the content of the light diffusing agent with respect to the light reflecting agent was 60% by weight or more, the comparative example having a small content of the light diffusing agent was used. Compared with the reflective screen No. 1, the viewing angle, the horizontal light amount ratio and the peripheral light amount ratio were greatly improved. Although not shown in the table, this tendency was not changed when the content of the light diffusing agent with respect to the light reflecting agent was 500% by weight. In addition, the SG value itself calculated from the brightness of the screen surface and the illuminance of the light source tended to decrease as the content of the light diffusing agent with respect to the light reflecting agent increased. As a result, the image was not difficult to see due to the decrease in luminance. Rather, a clear image could be seen even at the periphery of the screen because the horizontal light amount ratio and the peripheral light amount ratio were excellent.

In the reflection type screen of Comparative Example 2 using a pearl pigment as a light diffusing agent, the SG value and the contrast ratio were good, but the viewing angle was extremely narrow, and both the horizontal light amount ratio and the peripheral light amount ratio were low. Was.

The reflective screen of Comparative Example 3 using silicon dioxide as the light diffusing agent showed good values for viewing angle due to low front luminance, but low SG value and low contrast ratio. Further, in the reflection type screen of Comparative Example 4 using a pearl pigment as a light reflector, both the SG value and the contrast ratio were low, and when an image was actually projected and viewed, the image was considerably dark.

From the above results, it can be seen that the reflective screen of this embodiment shows a practical SG value and contrast ratio, and also has an excellent viewing angle, horizontal light amount ratio and peripheral light amount ratio.

[0036]

As is clear from the above examples, the reflective screen of the present invention can obtain a practical SG value and a wide viewing angle by incorporating a relatively large amount of a light diffusing agent into the reflective layer. In particular, a still image with many white backgrounds such as a personal computer image can be clearly displayed. Further, since the reflection type screen of the present invention has a very excellent horizontal light amount ratio and peripheral light amount ratio, it is possible to view an image without uneven brightness even on a large screen of 80 inches or more.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a reflection type screen of the present invention.

FIG. 2 is a sectional view showing another embodiment of the reflection type screen of the present invention.

FIG. 3 is a view for explaining a method of measuring a horizontal and peripheral light amount ratio in a reflective screen.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Light diffusive reflective layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takaaki Kato 4-6-35 Suzuya, Yono-shi, Saitama Pref. Inside the Kimoto Development Laboratory Co., Ltd. (72) Inventor Hideo Takamoto 4--4 Nihonbashi Honishicho, Chuo-ku, Tokyo No. 20 Izumi Co., Ltd. Tokyo Branch Office (72) Inventor Omura Teijiro 4-4-2 Nihonbashi Honishicho, Chuo-ku, Tokyo Izumi Co., Ltd. Tokyo Branch Office

Claims (6)

[Claims] 1. A reflective screen for a projector comprising a substrate and a light-diffusing reflective layer comprising a binder resin, a light-reflecting agent and a light-diffusing agent, wherein the light-diffusing reflective layer comprises a light-diffusing agent. A reflection type screen for a projector characterized in that the content is 50 parts by weight or more based on 100 parts by weight of the light reflecting agent. 2. A reflection type screen for a projector according to claim 1, wherein said light diffusing agent comprises transparent resin particles. 3. The reflective screen for a projector according to claim 1, wherein the average particle size of the light diffusing agent is in a range of 2 to 25 μm. 4. The reflection type screen for a projector according to claim 1, wherein said light reflecting agent is made of a non-leafing type scale-like aluminum paste. 5. The reflective screen for a projector according to claim 1, wherein the light reflecting agent is contained in an amount of 10 to 80 parts by weight based on 100 parts by weight of the binder resin. 6. A light-shielding layer according to claim 1, wherein a light-blocking layer is provided on a surface of said substrate opposite to a surface on which said light-diffusing reflection layer is provided. Reflective screen for projector.