JPH0216498B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a transmissive blackstrive screen with good contrast for use in large television screens.

(Prior art) Conventionally, blackstrive screens with improved contrast include:
By making the screen on the incident side of the projected image a rough surface and applying anti-reflection treatment to the screen surface on the exit side of the projected image, that is, on the viewing side, or by making the screen material itself have a slight light absorption property. Measures have been taken to prevent room illumination light from being reflected on the screen surface and reducing the contrast of the projected image.

However, applying a good anti-reflection finish to the screen surface increases the cost due to the complicated process, and providing the screen material itself with light absorption properties reduces the amount of transmitted light of the projected image itself. It had the disadvantage of becoming.

As a method to eliminate these drawbacks, a lenticular sheet made of transparent synthetic resin with the light refraction directions perpendicular to each other is provided on both sides, and by limiting the light dispersion angle in the horizontal and vertical directions of projection, the contrast can be improved. Screens that improve this have been proposed.

This method gives directionality to the light emitted from the screen, allowing more of the projected image's light to enter the viewer's eyes, thereby increasing the ratio to the constant light in the room and improving contrast. However, it is difficult to obtain sufficient contrast because indoor light reflected from the screen surface still enters the viewer's eyes.

Furthermore, Japanese Patent Application Laid-Open No. 56-38035 proposes a method that solves the above drawback by providing a light absorbing layer only on the projection image exit surface of a screen made of a lenticular sheet, excluding the light transmitting part. has been done.

(Problem to be Solved by the Invention) In the device disclosed in Japanese Patent Application Laid-Open No. 56-38035, a convex strip is formed on the back surface of the lenticular lens surface corresponding to the non-light condensing part of the lenticular lens, and This is a lenticular sheet with a light-absorbing layer provided on the stripes, but since the light-absorbing layer is formed by a printing method, it has the disadvantage that the appearance quality of the screen deteriorates due to uneven coating. It is often necessary to print etc.

Furthermore, since a solvent is used when printing ink, it is necessary to dry and remove the solvent after application, and if this is not done properly and the sheets are stacked or used, blocking may occur between the sheets or light may be blocked. The disadvantage is that the absorption layer may peel off or become uneven, and since curable ink has high durability after curing, if it is used for the light absorption layer, it requires aging to harden. The life of the ink is limited by the pot life, and it is extremely difficult to maintain constant physical properties for long-term continuous production.

Therefore, the present invention eliminates the drawbacks of ink printing by forming a light absorption layer on the convex stripes formed on the back side of a lenticular sheet by thermal transfer, and provides a method for use in large-sized televisions with good contrast. The object of the present invention is to provide a method for manufacturing a transmission type screen that allows a blackstrive screen to be manufactured easily and at low cost.

(Means for Solving the Problems) In order to achieve the above objects, the present invention has the following features:
The present invention provides the following method for manufacturing a transmission screen.

That is, manufacturing a transmission screen in which a lenticular surface is formed on one surface of a transparent substrate, a protruding strip is formed on the other surface at a portion other than the lenticular light condensing section, and a light absorption layer is provided on the protruding strip. During the step of forming a lenticular surface on a transparent substrate using a lenticular mold, a concave groove portion is formed using a mold having a convex portion on the back surface of the molded lenticular surface at a position corresponding to the light condensing portion. Transfer paper that contains a light absorber and is laminated with a resin that can be thermally bonded to the lenticular sheet on the protruding stripes between the concave grooves formed at positions other than the light condensing section. This method of manufacturing a transmission screen is characterized in that a light absorbing layer is formed by pressing with a hot pressure mold and thermally bonding only a resin layer containing a light absorbing agent.

(Function) The present invention forms a convex strip on the back surface of a lenticular sheet or a screen made of a Fresnel lens and a lenticular sheet by molding, and then forms a light absorption layer by thermal transfer. It forms the

(Example) Examples will be described below with reference to the drawings.

First, the configuration of the screen according to the present invention will be explained as follows.
To explain the figure, 1 is a light source, 2 is a Fresnel lens sheet for making the light rays from the light source 1 parallel lines, and 3 is its lens surface.

4 is a lenticular sheet for widening the viewing angle, and its lens surface 5 faces the Fresnel lens sheet 2 side, and the back surface 7 corresponds to the non-light transmitting portion 6 of the concave portion of the lens surface 5. There are protrusions 8 at the positions, and between the protrusions 8 there are grooves 9. The concave groove portion 9 is a light transmitting portion, and a light absorption layer 10 is formed on the surface of the convex strip portion 8.

The reason why the contrast in a screen with such a configuration increases is that the transmitted light brightness of the maximum part of the transmitted light of the image projected from the screen is Tmax,
The transmitted light brightness at the minimum part is Tmin, the reflected light intensity of a normal screen without a light absorption layer is R, the reflection intensity of a screen with a light absorption layer is R', and the normal screen and the screen with a light absorption layer are Let the respective contrasts be C and C', C=Tmax+R/Tmin+R, C'=Tmax+R'/Tmin
+R′.

Here, since Tmax>Tmin and R>R', C-C'=(Tmax-Tmin)(R'-R)/(Tmin+R)
(Tmin+R')<0, and the contrast is greater in a screen with a light absorption layer.

Next, the manufacturing method of the present invention will be explained.

In FIG. 2, reference numeral 11 denotes a T-die for extruding a transparent substrate or a translucent substrate material 12 kneaded with a light diffusing agent into a sheet.
4, and embossing rolls 15 are provided below.

The relationship between the lenticular mold roll 13 and the embossing roll 15 is as follows:
The concave arc-shaped part 16 and the chevron-shaped convex strip part 17 on the mold surface of No. 3 are
Disc part 18 and valley part 19 of embossing roll 15, respectively
The embossing roll 15 can be moved in the axial direction to adjust the relationship between the two.

A transparent substrate extruded from a T-die 11 or a translucent substrate material kneaded with a light diffusing agent, that is, a lenticular sheet material 12 is placed between a lenticular mold roll 13 and a press roll 14 with a lens surface 5 on the surface. are formed, and at the same time, protrusions 8 and grooves 9 are formed on the back surface 7 between the lenticular mold roll 13 and the embossing roll 15.

As this lenticular sheet material 12,
Transparent resin such as vinyl chloride, acrylic, polycarbonate, polystyrene, polyester, or
A translucent resin mixed with a light diffusing agent such as glass beads, silica, or talc is used.

The lenticular sheet 4 in which the lens surface 5 is formed on the front surface and the uneven stripes 8 and 9 are formed on the back surface 7 in this way,
It is cut to the required length as a lens.

Next, this cut lenticular sheet 4
A light absorbing layer 10 is formed on the convex stripes 8 on the back surface 7 of the paper, as shown in FIG. The light absorbing layer 21 of the transfer paper 22 is passed between the pressure roll 23 and the back surface 7 of the lenticular sheet 4 and rotated or fed together in the direction of the arrow. is peeled off from the peelable film 20 side and thermally bonded to the convex strips 8 on the back side 7 of the lenticular sheet 4 to form the light absorption layer 10.

In this case, the transfer paper 22 can be thermally bonded to the lenticular sheet 4 to a peelable film 20, for example, a synthetic resin film such as polyester, nylon, cellophane, olefin, etc., or a base film made by laminating silicone, olefin, etc. on paper. resins such as vinyl chloride, acrylic, urethane,
The light absorbing material layer 21 is laminated by applying an ink made of polyamide or the like and a light absorbing agent such as metal powder, carbon, etc. using a conventional coating method such as a gravure method, a roll coating method, or a silk screen method. be.

In addition, the transfer paper may be provided with a layer for the purpose of mold release or surface protection between a peelable film like a normal transfer paper and a light absorbing material layer, or a layer may be provided for the purpose of mold release or surface protection. A heat seal layer may be provided to enhance adhesion to the lenticular sheet.

The transfer method is not limited to the roll transfer method as shown in FIG. 4, but may be a flat plate method.

(Effects of the Invention) As described above, the present invention provides a light absorbing layer on the convex stripes on the back side of the lenticular sheet by the transfer method, so the light absorbing layer is formed by the printing method. It has the following advantages compared to:

a By controlling the thickness of the resin layer formed on the transfer paper, it is easy to control the thickness of the light absorption layer after being transferred onto the screen, and the thickness can also be formed uniformly.

Therefore, it is possible to solve the problem of deterioration in the appearance quality of the screen due to uneven coating that occurs in printing methods.

In addition, with the printing method, it was often necessary to perform overprinting to obtain the required density of the light absorption layer, but with the present invention, it is easy to do this by setting the resin layer on the transfer paper to the desired thickness and density. A highly concentrated light absorption layer can be obtained.

b. When printing with ink, a solvent is used, so it is necessary to dry and remove the solvent after application. If this is not done properly and the sheets are stacked or used, blocking may occur between the sheets. The light absorption layer may peel off or become uneven.

According to the present invention, the light-absorbing layer becomes stable immediately after its formation, so there is no problem as described above.

c Curable ink has high durability after curing, so it is often used for the light absorption layer. Although such curable ink requires aging in order to be cured, the present invention does not require such a step, so the process can be simplified.

Furthermore, the lifespan of curable inks is limited by the pot life, and it is extremely difficult to maintain constant physical properties of the ink during long-term continuous production. However, it is possible to form a uniform light absorption layer.

[Brief explanation of drawings]

The drawings relate to the manufacturing method of the present invention, and FIG. 1 is an explanatory drawing of the screen configuration to be manufactured;
Fig. 2 is a schematic side view of the apparatus for carrying out the process, Fig. 3 is a front view of the lenticular mold roll and embossing roll, and Fig. 4 is a schematic diagram showing the state in which the light absorbing material layer is transferred from the transfer paper. FIG. DESCRIPTION OF SYMBOLS 1... Light source, 2... Fresnel lens sheet, 4... Lenticular sheet, 8... Convex strip, 10... Light absorption layer, 11... T-die, 12... Transparent, translucent substrate material, 13... Lenticular mold roll, 14... Press roll, 15... Embossing roll, 20... Peelable film, 21... Light absorption layer, 22... Transfer paper, 23
...Heat pressure roll.

Claims (1)

[Claims] 1. In the production of a transmission type screen in which a lenticular surface is formed on one side of a transparent substrate, a protruding strip is formed in a region other than the lenticular light collecting section on the other surface, and a light absorption layer is provided on the protruding strip. During the process of forming a lenticular surface on a transparent substrate using a lenticular mold, a concave groove portion is formed using a mold having a convex strip at a position on the back surface of the molded lenticular surface corresponding to the light condensing portion. Then, a transfer paper containing a light absorbing agent and laminated with a resin that can be thermally bonded to the lenticular sheet is placed on the protruding stripes between the grooves formed at positions other than the light condensing section. 1. A method for producing a transmissive screen, which comprises forming a light absorption layer by thermally bonding only a resin layer containing a light absorption agent by pressing with a hot pressure mold.