JP2737093B2 - Reflective projection screen - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection screen, and more particularly to a reflection type screen for projecting a moving image such as a movie.

[0002]

2. Description of the Related Art Generally, a screen used for projecting a slide or OHP, or for projecting a movie or a video is formed by laminating a white polyvinyl chloride (PVC) film on a dark backing sheet. Conventional screens have low reflectance and dark images, so if you do not darken the room, you cannot see the images. Moreover, because of the low diffusivity, only within a limited range of angles to the screen surface,
I can't see the video.

There is a screen in which glass beads are adhered to a PVC film in order to increase the reflectance and the diffusivity. However, the screen has irregularities on the surface and is easily stained. There is a disadvantage that it is easily peeled off. When this kind of screen is used as a roll-up type screen, there is a problem that the glass beads gradually fall off as the screen is rolled and stretched many times.

The above-mentioned dark backing sheet and white PV
In a screen made of a C film, a metal deposition layer is provided as a reflective layer on a white PVC film, and a translucent PVC film containing a pearl pigment is laminated thereon,
A surface having a specific embossed surface has been proposed (Japanese Utility Model Application Laid-Open No. 64-40835).

[0005] A screen having a metal reflective layer has too high a light reflectance to cause halation, making it difficult to view an image. In addition, in order to form a metal vapor deposition layer as a reflective layer, a plastic sheet with strong adhesion to the vapor deposition layer
The disadvantage is that such plastic sheets tend to wrinkle, although (mainly polyester sheets) must be used. In other words, the bending that occurs when the screen is transported or wound up remains, and is conspicuous due to the high reflectance. These problems are serious when a large screen, for example, a 100-inch screen is used.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reflective screen which has appropriate diffusivity and reflectivity as a projection screen, is hardly wrinkled, and is easy to handle.

[0007]

According to one embodiment of the reflection type projection screen of the present invention, as shown in FIG. 1 showing a cross section, a glass fiber is provided on a light absorbing layer (5) which is a dark plastic sheet. Base cloth (4), a white opaque and flexible plastic base sheet (3), a reflective layer (2) printed with an ink containing a glitter pigment or calcite powder, and a glitter pigment or calcite powder. A light-diffusing layer (1) made of kneaded translucent and flexible plastic is sequentially provided, and embossed (9) is applied to the surface.

The plastic used for the base sheet and the light diffusing layer is not particularly limited as long as it is flexible. For example, polyvinyl chloride is representative. In addition, polypropylene and polyethylene are suitable. In particular, a soft material obtained by adding about 50 to 60 parts by weight of a plasticizer to 100 parts by weight of polyvinyl chloride is preferable. The thickness of the base sheet may be in the range of 0.05 to 1 mm.

As the base sheet, a sheet formed by kneading a white pigment and a glittering pigment into a plastic can be used, but a large amount of the coarse glittering pigment is dispersed uniformly and uniformly in the plastic. It is difficult to do so, and it is not advisable to use a large amount of expensive brilliant pigments, and since such a sheet has low flexibility, only a white pigment is kneaded to form a film. It is advantageous to print inks with glitter pigments.

The following are examples of glitter pigments. (A) What is called a pearl pigment, specifically, crushed inner part of shell shell or pearl, mica, fine particles of mica baked with TiO ₂ or iron oxide,
(B) metal powders, specifically fine particles of preferably 1 to 120 μm, such as copper, aluminum, brass, bronze, gold, silver, etc., (c) crushed plastic film fragments, for example, polyethylene terephthalate film. Such metal, usually aluminum, is evaporated and ground. These brilliant pigments preferably have a scaly shape. When the surface of the scaly body is arranged in parallel with the surface of the base sheet, high-brightness diffuse reflection can be achieved.

The calcite powder has an average particle size of 2 to 20 μm.
Is preferable, and the particle size distribution is preferably as narrow as possible. For example, when the average particle size is 5 μm, 80
The particle size distribution is such that the weight% or more falls within the range of 3 to 7 μm.

The amount of the glitter pigment or calcite powder added to the plastic used as the light diffusion layer is preferably 0.5 to 10% by weight, particularly preferably about 2% by weight.

The ink used for printing on the base sheet is an ink in which a glitter pigment or calcite powder is dispersed in a usual ink vehicle. Examples of the vehicle include polyvinyl chloride, vinyl chloride-vinyl acetate copolymer , Acrylic resin, polyurethane, polyester and the like. It is preferable that the proportion of the glitter pigment in the ink is high, but if the proportion of the vehicle is too low, it becomes difficult to form a print layer on the base sheet. Therefore, the ink composition is 5 to 50 parts by weight of the vehicle with respect to 100 parts by weight of the pigment. Parts are preferred. The thickness applied by printing is usually 1
About 10 μm.

This type of ink in which a coarse-grained brilliant pigment is dispersed tends to cause unevenness during printing, so that printing is not performed to a desired thickness at one time, but is performed to a thickness of a fraction. It is preferable to perform overprinting which is repeated several times to obtain a desired thickness in all the layers, since the light-diffusing layer can have high reflection performance.

When calcite powder is used, the composition of the ink is preferably in the range of 10 to 100 parts by weight, particularly 10 to 50 parts by weight of the vehicle with respect to 100 parts by weight of calcite powder for the same reason as described above.

The printing may be performed by a known method such as a printing method such as a gravure method or a silk screen method, or a coating method such as spray coating or roll coating. The thickness of the printed layer is 1 μm in a dry state. That's all you need.

When the reflection layer is not provided, the thickness of the light diffusion layer is preferably in the range of 0.04 to 0.8 mm based on the consideration of reducing the amount of attenuation of the reflected light and keeping the image bright. is there. When a reflective layer is provided, the range of 0.05 to 1 mm is appropriate from the viewpoint of increasing the half-value angle by increasing the thickness of the light diffusion layer because the amount of reflected light is little attenuated.

The base fabric is used to enhance the dimensional stability of the screen, and when used as a roll-up screen, it is required to work to prevent the lowered screen from sagging. In addition, when the screen stored by winding up is to be rewound and used for projection again, the image is distorted if the curl remains, so that the base fabric is required to have sufficient elasticity and rigidity. What satisfies these requirements is a woven or nonwoven fabric of glass fiber, or a plastic sheet such as polyester or triacetyl cellulose having a large number of micropores and flexibility.

The plastic sheet serving as the light absorbing layer is formed by kneading a dark color, for example, black, dark brown or dark blue pigment, into a plastic material similar to that of the base sheet. The thickness of this sheet is preferably about the same as the base sheet or the total thickness of the base sheet, the reflective layer and the light diffusion layer, so that the screen is well-balanced in the thickness direction, which is preferable.

In the above screen, a laminate of a plastic sheet to be a light absorbing layer, a reflective layer and a light diffusing layer is integrated by heating and pressing with a glass fiber base cloth interposed therebetween.
At the same time, it can be manufactured by embossing the surface of the diffusion layer. The integration may be performed by any of a heat fusion method and a dry lamination method.

The lamination of the substrate sheet and the light diffusion layer can be performed by laminating a plastic sheet to be the light diffusion layer on the reflection layer on the substrate sheet, and a plastic sol to be the light diffusion layer. It is also possible by coating.

The embossing pattern may be a pattern in which corrugations intersect at 90 ° as commonly used in a conventional reflection type screen, and may be any other pattern such as a grained tone or a hairline tone. If the audience is not only in front of the screen but also on the left and right, it is necessary to diffuse the light with a large half-value angle in the horizontal direction, which is achieved by embossing which provides a group of semi-cylindrical lenticular lenses with a vertical axis. It is suitable.

As shown in FIG. 2, another embodiment of the reflection type projection screen of the present invention is a white opaque and flexible plastic base sheet having a light absorbing layer (6) which is a solid printing layer of dark ink. On the non-printing surface of 3), a base fabric of glass fiber (4), a reflective layer (2) printed with an ink containing a glitter pigment or calcite powder, and a glitter pigment or calcite powder were kneaded. A light diffusion layer (1) made of a translucent and flexible plastic is provided in order and embossed (9) is applied to the surface.

The base sheet, the base cloth, the translucent plastic sheet, the pigment and the like may be the same as those described above. The light absorbing layer may be formed by a known method such as a gravure method or a screen method using ordinary printing.
The screen may be manufactured by a method similar to the above, in which the base sheet and the translucent plastic sheet are integrated by heating and pressing with the base cloth therebetween, and simultaneously embossing is performed.

On the surface of the reflection type projection screen of the present invention,
As shown in FIG. 3, if the outer frame (10) is printed by a suitable means such as silk screen printing with dark ink,
This is the recommended mode because the edges of the image are properly trimmed and the screen is sharper.

Further, as one of the preferable embodiments for improving the performance of diffusing and reflecting light and increasing the half-value angle, the texture of the fibers constituting the base fabric and the unevenness of the weave are formed on the surface of the base sheet. Some have emerged. The minute irregularities on the surface of the base sheet contribute to the light diffuse reflection performance.

[0027]

According to the projection screen of the present invention, a light-diffusing layer of translucent plastic containing a brilliant pigment is provided on a white, opaque sheet material so that the light-diffusing layer has an appropriate diffusivity for a reflective screen. High reflectivity has been achieved.

Light projected from the projector onto the screen is partially reflected by the diffusion layer, partially reflected in the surface of the base sheet while traveling in the layer and undergoing slight diffusion, and passes through the diffusion layer again. Willingly emanates from the screen. Embossments on the screen surface also provide refraction as light enters and exits the surface. In this manner, reflection with appropriate diffusion is performed, in which the reflected light is not limited to a specific direction but goes to a wide range of angles. Due to the presence of the reflective layer, a high rate of reflection is performed, and high luminance can be obtained on the screen surface.

[0029]

EXAMPLES [Example] White PVC calendar sheet (DOP: 0.13 mm thick)
60 phr) as a base sheet, and a brilliant ink having the following composition is gravure-printed thereon with 100 parts by weight of a vehicle (PVC) 20 parts by weight of a pigment (titanium-coated mica) so as to have a dry thickness of 3 μm. A reflection sheet was obtained.

A 0.28 mm thick black PVC sheet (DO
P: 60 phr) as a light absorbing layer, on which a glass fiber woven base fabric, the above-mentioned reflection sheet, and about 2% by weight of pearl pigment (titanium-coated mica) are kneaded and extruded to form a 0.15 mm thick half. Transparent PVC sheet (DOP: 60ph
r) and a grained embossing plate were sequentially stacked, integrated by hot-press doubling and embossed. When the half value angle of the obtained reflection type projection screen of the present invention was measured, it was 45 °. The half-value angle is an inclination with respect to a vertical line in a direction in which the brightness becomes half in the horizontal direction with reference to the brightness in front of the screen.

On the surface of the screen obtained as described above, black ink was silk-screen-printed to form an outer frame of a black line having a width of 3 cm, and the book was surrounded by a square having a diagonal length of 100 inches. A preferred embodiment of the reflective projection screen of the invention was produced.

Comparative Example A reflective projection screen was manufactured in the same manner as in Example 1 except that the translucent PVC sheet was omitted. The half-value angle of the obtained screen was 25 °.

[0033]

The projection screen of the present invention can project a high-quality image on a large screen with high luminance, and there is no great difference in the brightness depending on the viewing direction of the screen. Can be used in combination with the projection means.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining an example of a projection screen of the present invention.

FIG. 2 is a view similar to FIG. 1, for explaining a modification of the projection screen of FIG. 1;

FIG. 3 is a plan view for explaining a general preferred embodiment of the projection screen of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light diffusion layer 2 Reflection layer 3 Base sheet 4 Base cloth 5, 6 Light absorption layer 9 Emboss 10 Outer frame

Claims (3)

(57) [Claims] 1. A light-absorbing layer (5) which is a dark-colored plastic sheet, a base cloth (4) of glass fiber, a white opaque and flexible plastic base sheet (3), a powder of brilliant pigment or calcite. A reflective layer (2) printed with an ink containing, and a light diffusion layer (1) of a translucent and flexible plastic kneaded with glitter pigment or calcite powder, and embossing (9) the surface. Reflective projection screen. 2. A glass fiber base cloth (4) on a non-printing surface of a white opaque and flexible plastic base sheet (3) having a light absorbing layer (6) which is a solid printing layer of dark ink. A reflective layer (2) printed with an ink containing a glitter pigment or calcite powder, and a translucent and flexible plastic light diffusion layer (1) kneaded with the glitter pigment or calcite powder are provided in this order. Reflective projection screen with embossing (9) applied to it. 3. The screen according to claim 1, wherein an outer frame (10) is printed around the surface of the light diffusion layer with dark ink.