JPH06175228A - Reflection type projection screen - Google Patents

Abstract

PURPOSE:To provide the reflection type projection screen which can assure bright images without the disturbance in videos by the stray light which does not focus at a high-density light diffusion reflection layer. CONSTITUTION:A net layer 2 of tri- to octagonal shapes of a black color formed of twisted yarn or monofilaments having 0.8 to 2.0mm aperture diameter and 0.03 to 0.06mm yarn diameter, the high-density light diffusion reflection layer 3 and a dimension stabilizing base material sheet 4 are laminated in this order on a translucent light diffusion layer 1 consisting of a soft plastic sheet constituted by forming microrugged patterns la on the photodetecting surface of a resin layer dispersed with bright pigments. Further, white or black pigments are further added at need to the dimension stabilizing base material sheet 4 and in some cases, a white opaque resin layer 5 or a black opaque resin layer 6 is laminated successively on the high-density light diffusion reflection layer of this sheet.

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 reflective screen for projecting moving images such as movies and projection televisions.

[0002]

2. Description of the Related Art A screen for projecting slides or OHPs, or for projecting movies or videos is generally a black backing sheet laminated with a white polyvinyl chloride sheet. Such a screen has a uniform isotropic diffusivity in all directions and an appropriate reflectance of projected light, and it is a wrinkle-resistant and easy-to-handle reflective projection screen that is a dark plastic sheet made of black opaque resin. In the layer, a glass fiber base cloth, a reflection sheet having a reflective layer printed with an ink containing a bright pigment or calcite powder on the image-receiving surface of a white opaque flexible substrate sheet, and a fine powder of the bright pigment or calcite A white opaque, flexible plastic substrate sheet that has a light-diffusing layer of a semi-transparent and flexible plastic resin containing a film, and has a projection screen with an embossed surface and a light-absorbing layer that is a solid printing layer of dark color ink. On the non-printed surface of the, a glass fiber base cloth, and a semi-transparent flexible plastic that becomes a light diffusion layer in which a bright pigment or calcite fine powder is kneaded. The lower surface of Kkushito provided a sheet having an ink layer containing a fine powder of the bright pigment or calcite in the order, the reflection type projection screen having been subjected to embossing is proposed to the surface. (Practical application 3-2462
issue)

When such a reflection type projection screen is used, it is sometimes white due to the action of a double image due to stray light (an image which is not focused on the reflection layer surface by light other than the image passing through the semitransparent light diffusion layer). However, there is a problem in that the contrast and the sharpness are lacking. In addition, this type of screen causes unevenness on the surface of the projection film due to the weave of the glass fiber base cloth or nonwoven cloth during the laminating process, uneven texture, etc., and the moire caused by interference between the pixels and these uneven shapes. However, there is a problem that it is difficult to obtain a shape having stable optical characteristics.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to have stable and appropriate optical characteristics, to prevent moire and image distortion on the projection surface, and to always secure a clear image with high contrast even in a bright place. It is to provide a reflective screen that can be used.

[0005]

The reflection type projection screen of the present invention comprises a resin layer in which a glittering pigment or a fine powder of calcite is dispersed, and a soft plastic resin sheet in which a light-receiving surface is provided with a fine concavo-convex pattern. On the non-light-receiving surface of the semi-transparent light diffusion layer, the opening diameter is 0.8 to 2.0 mm and the thread diameter is 0.0.
3 to 3 made from twisted yarn or monofilament of 3 to 0.06 mm
~ Octagonal black net, a dense light diffuse reflection layer made of a resin layer in which a bright pigment is dispersed, and a dimensionally stable and flexible base sheet are laminated in this order And

The shape of the black net is defined by the size and density of pixels, and the following requirements are required. That is, this type of reflective projection screen has a minimum size of 100c.
The number of pixels to be used and projected at m or more is 525 in the case of a normal television and 1125 in the case of a high-definition television. Therefore, the period and size of the pixel are
100 cm / 525 to 100 cm / 1125 = 19
It is from 00 μm to 890 μm. The size of the pixel is 0.8 to 0.8, which corresponds to the size of the pixel in view of the size of the pixel.
The aperture diameter is 1.8 mm, and the thread diameter is about one digit smaller than the pitch and has a strength of about 0.08 mm or less. It can be said that the larger the yarn diameter in the present invention, the better in consideration of giving strength to the projection screen, but the preferable numerical value was 0.04 to 0.06 mm. The aperture diameter described in the present invention is the minimum length of one side of the net aperture portion.
The shape of the net is slightly different from the shape of the pixel, the shape of the light diffusing micro-relief pattern, and the shape required for the black net depending on the mechanism, etc. In particular, a regular polygon having 6 to 8 sides is preferable, and a combination of hexagonal turtle shells is preferable.

The net material must have heat resistance of 100 ° C. or higher, which is the processing condition for the laminated sheet of the present invention, and synthetic fibers such as polyester, polyamide, rayon and acrylic as well as natural fibers such as cotton and hemp can be used. It can also be a material. The warp / weft yarns that compose the net include monofilament / monofilament, monofilament / multifilament, and multifilament / multifilament, any of which can be used. Natural fiber is heat resistant,
Although it is excellent in stackability, it is not suitable for projection screens that require precision because it is a multi-filament in which short fiber threads are twisted together, which may cause thread fluff and damage the image. In the present invention, polyamide multifilament / multifilament, which is a synthetic fiber free from yarn fluff, is a preferable material because it has good post-processability.

The dimensional stable base sheet imparts strength and dimensional stability to the screen, and is flexible enough to be wound in a cylindrical shape having a minimum diameter of 30 mm in which the projection screen is usually stored in a roll shape. Maximum tension of 2 when winding / unwinding
Withstands tension of 0 Kg / m width, the most important factor is
There is no deformation such as slack, curl or wrinkle after repeated use of winding / unwinding, and there is no translucent light diffusing layer on this surface, and unnecessary unevenness such as texture and unevenness does not appear on the outermost surface. It is necessary that it has smoothness, and that it does not hinder the heat and tension of the processing steps for laminating and printing other materials. Materials that meet these requirements have an elastic limit of 60 kg /
cm ² or more, Young's modulus 2.5 × 10 ⁴ Kg / cm ² or more, bending elastic modulus 3.5 × 10 ⁴ Kg / cm ² or less, thickness 3
It is preferable that the center line average roughness and waviness of JIS-B-0601 are both 5 μm to 200 μm and 100 μm or less. A dimensionally stable substrate sheet having these characteristics is required by a single plastic sheet or by laminating, and those sheets must also have the optical characteristics of the projection screen such as light absorption, whiteness and reflection. Is desirable.

The plastic sheet for the dimensionally stable substrate sheet satisfying these requirements includes transparent, white or black stretched polyethylene terephthalate, polybutylene terephthalate, stretched polyamide nylon 6 and nylon 66 (trademarks), Synthetic paper and natural cellulose produced from a single sheet or low-foaming plastic sheet based on cellulose triacetate, polystyrene, polyarylate, polycarbonate, Noryl (registered trademark of GE), polyether sulfone, polymethylmethacrylate, etc. Examples include opalescent parchment paper that is treated with sulfuric acid and is not delaminated on paper containing titanium white. Further, these sheets may be used as a single layer or may be used by laminating a plurality of sheets, as long as they satisfy the above-mentioned performance. The dense light diffusing / reflecting layer and the semitransparent light diffusing layer laminated on these sheets, and if necessary, the white and dark opaque resin layers laminated on the back surface have a higher elongation than the dimension-stable substrate sheet. Use by laminating a large soft plastic sheet. The soft plastic sheet that can be used in this case has, for example, an average degree of polymerization of 1000 to 2000, and a plasticizer containing 30 to 70 parts by weight of dioctyl phthalate (DOP) as a soft polyvinyl chloride, polyethylene, ethylene / vinyl acetate copolymer ( There are unstretched sheets such as EVA), ionomer, ethylene / ethyl acrylate copolymer (EEA), ethylene / acrylic acid copolymer (EAA), methylpentene polymer and polybutene.

The dense-density light diffusing / reflecting layer may be a layer formed by kneading a white pigment and a glittering pigment into plastic, and using a film, but a large amount of the coarse-grained glittering pigment is uniformly applied to the plastic. It is difficult to disperse in it, and it is not a good idea to use a large amount of expensive bright pigment,
A layer containing a large amount of inorganic material has reduced flexibility. Therefore, it is advantageous to form an ink containing a bright pigment on a sheet formed by kneading only a white pigment and forming a film, by printing a primer layer if necessary.

Examples of the bright pigment are as follows. A pearl pigment produced by baking titanium oxide or iron oxide on mica, crushed pearls, mica, and flake-shaped fine particles of mica having an average particle size of 10 to 30 μm. Copper, aminium, brass, bronze, gold, silver, etc. 1-12
A metal powder that is fine particles of 0 μm. Pieces of polyethylene terephthalate film vacuum-deposited with the metals described above, usually aluminum. The shape of these bright pigments is preferably scale-like,
When the surface of the scaly body is arranged parallel to the surface of the base material reflection sheet,
Diffuse reflection can be achieved with high brightness. As a material, a pearl pigment composed of titanium oxide-coated mica is particularly preferable.

It is preferable that the calcite fine powder has a particle size distribution of 2 to 20 μm and that the particle size distribution is as narrow as possible. For example, when the average particle size is 5 μm, 80% or more of the grades are in the range of 3 to 7 μm. .

The plastic layer, which is a semi-transparent light diffusion layer, transmits the light rays once diffused and reflected by the dense light diffusion reflection layer, and further diffuses a part of the light rays to reduce glare on the screen and reduce the visual field. It also acts to spread appropriately. The amount of the luster pigment or the calcite fine powder added thereto is 0.5 to 10% by weight, preferably 2% by weight.

Further, the dense-density light diffusing / reflecting layer efficiently reflects almost all of the projection layer and appropriately diffuses the reflected light rays. Since the thickness of the layer is only a few μm, it is preferably formed by printing or painting, and the ink used is an ordinary binder resin in which the bright pigment is dispersed in the highest concentration possible. The vehicle is formed by dissolving a vinyl chloride / vinyl acetate copolymer, an acrylic resin, a urethane resin, a polyester resin or the like in an appropriate solvent.
The ink composition is preferably in the range of 5 to 100 parts by weight, especially 10 to 50 parts by weight of the vehicle per 100 parts by weight of the above pigment, and is constituted by adding an ink auxiliary agent such as a surfactant. Further, it is desirable to select a material having good adhesion to the transparent bright embossing layer and the net for the resin composition of the ink binder, such as vinyl chloride / vinyl acetate copolymer,
Urethane compounds are preferred. When heat-sealing the dense light diffusive reflection layer and the net, in order to strengthen the adhesion, a heat-sensitive resin is applied on the dense light diffuse reflection layer, or the concentration of the bright pigment is 1/5 to 1 /. Print with low density light diffuse reflection ink lowered to 2. The thickness of the ink film needs to cover the entire surface of the printed sheet with a bright pigment.
0 μm and 2 to 4 μm are preferable.

An ink made of a material having a poor affinity with the vehicle, such as a bright pigment, is likely to cause unevenness during printing. Therefore, it is preferable to perform overprinting several times to use the ink for covering the entire surface. The amount can be reduced and the effect of light diffusion can be enhanced.

In the case of using the calcite fine powder, the ink composition should be as high as possible for the above reason.
1 to 10 vehicles for 100 parts by weight of fine calcite powder
A range of 0 parts by weight, particularly 10 to 50 parts by weight is preferable.

The coating can be carried out by a known technique such as printing by gravure, silk screen, spray coating, roll coating, etc., which uniformly covers the front surface and has a solid content of 1 μm or more. It is necessary. Further, since the dense light diffusive reflection layer facilitates fusion bonding of the net, it is possible to reduce the pigment concentration of the ink layer to impart heat-sensitive adhesiveness.

The thickness of the semi-transparent light diffusing layer is set so as to reduce the attenuation of the reflected light and keep the image bright when the dense light diffusing and reflecting layer is not provided, and the thickness is in the range of 80 to 100 μm. Appropriate. When the light diffusing / reflecting layer is provided, the amount of reflected light is less attenuated. Therefore, the range of 50 to 300 μm is suitable from the viewpoint of thickening the light diffusing layer and scattering the light rays to widen the half-value angle. Further, in order to prevent the surface from being contaminated due to the adhesion of dust, it is necessary to select and add a surfactant serving as an antistatic agent.

In order to further improve the optical characteristics of the reflection type screen, a white opaque resin layer may be laminated on the surface of the dimensionally stable substrate sheet opposite to the dense light diffusive reflection layer, and further a black opaque resin layer may be laminated thereon. preferable. For the white and black opaque resin layers, a resin having the same physical properties as the semitransparent light diffusion layer is used, and in the case of white, a white pigment such as titanium oxide is black so that the opacity is 90% or more. In this case, in addition to carbon black, a plastic sheet in which metal powder such as aluminum powder is mainly added and other colored pigments are appropriately added and dispersed is used.

Either the white opaque resin layer or the black opaque resin layer can also serve as the dimensionally stable substrate sheet. In that case, a white pigment, a black pigment, or the like is dispersed in a dimensionally stable substrate sheet, and in some cases, synthetic paper or the like obtained by subjecting these plastic sheets to low foaming processing is used. Further, these white opaque resin layer and black opaque resin layer may be formed by laminating previously formed sheets, and can be formed by painting or printing. In order to prevent the curl of the projection screen, it is desirable that layers having the same physical properties are laminated on both sides of the dimensionally stable substrate sheet.

To insert a net in the constituent layers of the reflection type projection screen of the present invention, as shown in FIG. 9, a net is applied to a semi-transparent diffusion layer and a dimensionally stable substrate sheet to form a dense light diffusion reflection layer. And is sandwiched between two metal endless belts having heaters at the top and bottom, and hot-pressure fusion is performed while moving. Before entering the nip roll, the net supply is a dancer roll that can move up and down, and controls to correct the distortion and turning of the net.

The method of integrally laminating the reflection type projection screen of the present invention may be either the above-mentioned heat-pressure fusion method or the dry laminating method which is carried out by applying an adhesive.
It can also be formed by embossing at the time of film formation of the semitransparent glittering plastic sheet, or by using an embossing plate and heat pressure at the time of heat pressure fusion.

The fine concavo-convex pattern is a pattern in which corrugations are crossed by 90 degrees as is commonly used in conventional reflection type screens, as well as a grain pattern, a satin pattern, a hairline pattern, a cylindrical lenticular lens, and a triangular prism. A lenticular lens, a fly's eye lens, etc. are optional. When the spectators are lined up not only on the front of the screen but also on the left and right, it is necessary to diffuse the light in the horizontal direction, and for this purpose, the minute concavo-convex pattern that forms the semi-cylindrical lenticular lens group with the vertical axis is formed. Suitable. Further, when pixels are arranged periodically in the vertical and horizontal directions as in the case of projecting a liquid crystal display type television, moire is caused by a random and aperiodic uneven pattern such as sand and satin. It is preferable because it does not occur.

If an outer frame is printed with a dark ink on the surface of the reflection type projection screen of the present invention as shown in FIG. 8 by an appropriate means such as silk screen printing, the edges of the image are trimmed. Is performed properly and has the effect of making the screen clearer.

[0025]

The projection screen of the present invention comprises a dimensionally stable substrate sheet, a dense light diffusive and reflective layer of a glittering ink,
A black net layer with a stray light prevention effect and a semi-transparent light diffusion layer made of soft plastic with a minute uneven pattern formed on top of each other in order to prevent the occurrence of interfering images due to stray light on the light receiving surface and at the same time provide appropriate diffusivity. And high reflectivity have been realized.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a method of manufacturing a reflection type projection screen according to the present invention will be described with reference to the drawings.

Example 1 As a dimensional stability base sheet, white polypropylene-based synthetic paper 4a (Oji oil:
Black solid printing 6a is applied to the back side of YUPO 300 μm,
On the opposite surface, brilliant ink having the following composition is gravure-printed so that the thickness when dried is 3 μm, and a resin having the same composition as the binder of the dense ink diffuse reflection layer 3 / and the brilliant ink is formed. Heat-sensitive adhesive layer 3 having a thickness of 3 μm when dried
a is provided. -Brightness ink composition Vinyl chloride / vinyl acetate copolymer Vinylite resin VAGH 10.0 parts Plasticizer 5.0 parts Stabilizer 0.5 parts Titanium oxide coating mica pigment 15.5 parts Ethyl acetate 30.0 parts Ethyl Cellosolve 17.0 parts Toluene 37.0 parts

The surface of the dense paper diffuse reflection layer of synthetic paper, the yarn diameter 0.
A hexagonal net 2 made of polyamide (nylon) dyed in black and made of a monofilament with a diameter of 06 m and an opening diameter of 1.2 mm, and a semi-transparent sand-like fine unevenness pattern 1a with a thickness of 200 μm containing a pearl pigment having the following composition A non-recessed pattern surface of the soft vinyl chloride sheet 1 having the above was heat-bonded with an endless press type heat laminator shown in FIG. 9 to obtain a reflection type projection screen. -Composition of translucent soft vinyl chloride sheet containing pearl pigment Vinyl chloride resin (average degree of polymerization = 1300) 100.0 parts Plasticizer DOP 60.0 parts Stabilizer Epoxidized soybean oil 2.0 parts Antistatic agent 1.0 Part Titanium oxide coating mica 1.0 part Obtained reflective projection screen of the present invention The half value angle of FIG. 5 was measured and found to be 35 degrees. The half-value angle is the inclination with respect to the vertical line in the direction in which the luminance is halved in the horizontal direction with reference to the luminance in front of the screen. Further, even when projected in a room illuminated with a fluorescent lamp, a clear image was obtained without conspicuous deterioration in image quality due to stray light and deterioration due to whitening, as compared with a product without a black net layer.

Example 2 White Biaxially Stretched Polyester Film 4b 100 μm as Dimensionally Stable Substrate Sheet
(Toray, opacity 98%) Titanium oxide coating Mica is replaced with carbon black 1%, and the black soft vinyl chloride sheet 6b of Example 1 is pasted with a polyurethane adhesive on the white polyester film surface. After the linear polyester / isocyanate-based primer treatment, the bright ink of Example 1 was used as the dense density light diffusive reflection layer 3 after two-color printing by gravure printing to a thickness of 3 μm, and the bright pigment was further reduced to 1/3. The diluted glittering ink of Example 1 was applied to the low-concentration light-diffusive reflection layer 3 so that the thickness was 4 μm.
b was printed to obtain a sheet having a dark-density light-diffusive reflection layer having heat-sensitive adhesiveness. A polyester hexagonal net dyed in black with a monofilament having a thread diameter of 0.06 mm and an opening diameter of 1.2 mm in this dense light diffusing and reflecting layer,
A semi-transparent soft vinyl chloride sheet 1 containing the pearl pigment having a thickness of 120 μm and a grain-like embossing plate were sequentially stacked, and integrated by hot pressure doubling, and an uneven pattern 1a was formed. The half-value angle of the resulting reflective projection screen of the present invention shown in FIG. 7 was measured and found to be 45 degrees. Further, even when projected in a room illuminated with a fluorescent lamp, a clear image was obtained without conspicuous deterioration in image quality due to stray light and deterioration due to whitening, as compared with a product without a black net layer.

(Example 3) White soft vinyl chloride sheet 5a (200 μm, opacity 9 as a white opaque resin layer)
8%) Stretched nylon film surface of a sheet obtained by sequentially laminating a stretched nylon film 4c25 μm as a dimensionally stable base sheet and a black soft vinyl chloride sheet 6b of Example 1 containing 1% of carbon black via a polyurethane adhesive 7 in order. As the dark-density light-diffusive reflection layer, the bright ink of Example 1 was gravure-printed in two colors to give a thickness of 3 μm, and a dark-density light-diffusive reflection layer 3 was obtained. The warp / weft threads are monofilament / multifilament thread diameters on this dense light diffusion / reflection layer, regular hexagonal hexagonal black net 2 of black nylon thread with 0.05 mm aperture diameter 1.2 mm, semi-transparent diffusion As a layer, a semi-transparent light-diffusing soft vinyl chloride sheet 1b containing the pearl pigment having a thickness of 120 μm and a grain-like embossing plate were sequentially stacked, and integrated by hot pressure doubling, and an uneven pattern 1a was formed. A black frame having a width of 3 cm was provided on the obtained screen surface by silk screen printing with black ink, and a reflection type screen of the present invention surrounded by a square shape having a diagonal line length of 2.5 m was manufactured. The half-value angle of the reflective projection screen of the present invention was measured and found to be 45 degrees. Further, even when projected in a room illuminated with a fluorescent lamp, a clear image was obtained without conspicuous deterioration in image quality due to stray light and deterioration due to whitening, as compared with a product without a black net layer.

[0031]

The reflection type projection screen of the present invention, which is composed of a plastic sheet of stable size and a black net, does not generate an interfering image due to stray light, and pixels are faithfully projected from the aperture of the net. It does not appear on the surface, and the image is not disturbed, the contrast is not lowered, whitening, and moire fringes do not occur. Also, the inserted and fixed net contributes to the dimensional stability of the screen.

[Brief description of drawings]

FIG. 1 is a basic sectional view of the present invention.

FIG. 2 is a diagram showing a cross section of claim 2;

FIG. 3 is a diagram showing a cross section of claim 3;

FIG. 4 is a tortoise shell type net of the embodiment.

FIG. 5 is a cross-sectional view of the reflective projection screen according to the first embodiment.

FIG. 6 is a sectional view of a reflective projection screen according to a second embodiment.

FIG. 7 is a sectional view of a reflective projection screen according to a third embodiment.

FIG. 8 is a plan view of a reflective projection screen according to a third embodiment.

FIG. 9 is a travel diagram of a three-layer laminator using an endless belt.

[Explanation of symbols]

 1 semi-transparent light diffusion layer 1a microscopic uneven pattern of the semi-transparent light diffusion layer 1b semi-transparent light diffusion vinyl chloride sheet 2 black net layer 3 dense light diffusion reflection layer 3a heat-sensitive adhesive layer 3b low concentration light diffusion reflection layer 4 dimensional stability Base material sheet 4a Synthetic paper 4b White polyester film 4c Stretched nylon film 5 White opaque resin layer 5a White soft vinyl chloride sheet 6 Black opaque resin layer 6a Black printing 6b Black soft vinyl chloride sheet 7 Adhesive layer 8 Outer frame dark color printing section 9 Dancer roll part 10 Nip roll part 11 Endless belt 12 Heater 13 Winding part

Claims (4)

[Claims] 1. A semi-transparent light diffusing layer (1) made of a soft plastic resin sheet, which comprises a resin layer in which a glittering pigment or fine powder of calcite is dispersed and which has a fine unevenness pattern (1a) on a light receiving surface. The aperture diameter is 0.8 mm to 2.0 on the light receiving surface.
mm, a 3-8 octagonal black net layer (2) formed from twisted yarn or monofilament having a yarn diameter of 0.03 to 0.06 mm,
A dense light-diffusive reflection layer (3) made of a resin layer in which a bright pigment is dispersed, and a flexible dimensionally stable substrate sheet (4) are laminated in this order to give a total thickness of 0.5 mm to 1. 5m
A reflective projection screen characterized by being m. 2. The reflection type projection according to claim 1, wherein a white opaque resin layer (5) is laminated on the surface of the dimensionally stable substrate sheet (4) opposite to the dense light diffusive reflection layer (3). screen. 3. The reflection type projection screen according to claim 2, wherein a black opaque resin layer (6) is further laminated on the surface of the white opaque resin layer (5) opposite to the dense light diffusive reflection layer (3). . 4. The reflection type projection screen according to claim 1, wherein the flexible, dimensionally stable substrate sheet (4) is a sheet having an opacity of 90% or more in which a white pigment is dispersed.