JPH0594731A - Dazzle preventing sheet for illuminating light display - Google Patents

Abstract

PURPOSE:To enhance visibility in the daytime and evening by superposing a transparent thin film and a clear light shielding thin film, on at least one side of which dark light shielding thin films are laminated, respectively. CONSTITUTION:A transparent thin film 3 and a clear light shielding thin film 1 are welded in an alternately superposed manner, to be sliced in the superposed direction, thus obtaining a striped dazzle preventing sheet 5. Dark light shielding thin films 2, 4 are laminated on one side of each thin film 3, 1, respectively. A rutile type crystalline structure of titanium dioxide is preferable for the clear light shielding thin film 1. Carbon black, iron oxide black and the like can be used as the dark light shielding thin films 2, 4. An adhesive is applied onto opposed surfaces of a set of the obtained dazzle preventing sheet 5, and further, polycarbonate films 7 are attached, thus obtaining a dazzle preventing sheet B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antiglare sheet for an illuminating display, and more particularly, it does not allow the illumination switch used in the interior of an automobile or the like, the letters, symbols on the nameplate, or the light of a design to be reflected on the window glass or the like. The present invention relates to the antiglare sheet for illuminated display bodies used for nameplates, key tops and the like.

[0002]

2. Description of the Related Art A conventional antiglare sheet is produced in the same manner as a single-layer colored or opaque sheet (hereinafter referred to as light shielding) or film (hereinafter referred to as thin film) prepared by using a pressure press or roll. Monochromatic transparent thin films were alternately laminated and joined, and sliced in the stacking direction to obtain a striped pattern antiglare sheet (see JP-A-51-44186 and JP-A-50-26885). In the light-shielding thin film, which is a component of such an antiglare sheet, a large amount of black, which has large light absorption and opacity in plastic, and a chromatic colorant that transmits light of a specific wavelength are dispersed. ing. For the transparent thin film, generally, highly transparent plastic is used. Usually, the striped antiglare sheet alone or the striped antiglare sheet having a monochromatic transparent film attached to at least one surface thereof with an adhesive is called an antiglare sheet.

[0003]

The above-mentioned conventional antiglare sheet improves the contrast of the display portion when illuminated, and when used in an automobile or the like, the illumination switch, the letters of the nameplate, and the light of the symbol are applied to the window glass. Adjust the visible angle range and the light blocking angle range so that they are not reflected in the image. In addition, the displayed information must be easily and clearly identified by the user regardless of whether or not there is illumination or incident light from the surroundings.

Usually, an appropriate color or character on the antiglare sheet
Although symbols and pictures are printed, when the above-mentioned printing is applied to the light source side like a conventional antiglare sheet, the light-shielding thin film inside absorbs a large amount of light and is opaque. Since a chromatic colorant that transmits light of a wavelength is dispersed, it appears dark due to the color tone of the light-shielding thin film during the daytime, and its visibility is inferior to that at night illumination. Also, in order to improve visibility in the daytime, white printing is applied on the viewing side of the antiglare sheet, and even if characters, symbols, or patterns are printed on it, the light from the light source is white printed at night. There was a disadvantage that the effect of the anti-glare sheet was not obtained due to scattering (see Japanese Utility Model Laid-Open No. 2-104389). The present invention is to solve the above-mentioned conventional problems, without impairing the original function of the antiglare sheet, maintaining the visibility during night illumination, and an antiglare sheet having improved daytime visibility. The challenge is to provide.

[0005]

Means for Solving the Problems In the antiglare sheet obtained by alternately laminating transparent thin films and light shielding thin films and joining them and slicing them in the stacking direction, , Studying adding the advantage of improving the visibility of the antiglare sheet proposed by Japanese Patent Application No. 3-75859 in the daytime and the evening, and paying attention to the lightness of the light-shielding thin film and its light hiding property As a result, the antiglare sheet has a configuration in which a dark-color light-shielding thin film is overlapped on at least one surface of the transparent thin film, and a dark-color light-shielding thin film is overlapped on at least one surface of the light-color light-shielding thin film. By doing so, the visibility during daytime / evening hours (unilluminated) is shared by the light-colored light-shielding thin film, and the dark-colored or opaque thin film can achieve effective light-shielding like a conventional antiglare sheet. Inspiration It had achieved the present invention the end of repeated trial and error.

To explain this, the light-shielding thin film of the anti-glare sheet of the present invention includes white, such as zinc white, titanium dioxide, titanium white, and lead white, which are generally well-known light-coloring colorants. Pigments, yellow lead, reddish yellow lead (orange chrome), yellow pigments such as cadmium yellow, or a combination thereof may be used, but the weather resistance and hiding power of the colorant,
Titanium dioxide is particularly preferable because it has low toxicity, brightness of color, stability and the like. The particle shape, particle size, and crystal structure are not particularly limited as long as they do not significantly affect visibility, but it is preferable to use a rutile crystal structure having a particle size of 0.5 to 5.0 μm.

The dark-color light-shielding thin film is a black pigment such as carbon black, graphite, iron oxide black, or the like, which is a generally well-known dark-coloring colorant, or the light-color light-shielding thin film used in the light-color light-shielding thin film. What has a large contrast with the colorant may be used. There is no problem even if it is a single substance or a mixture,
It can be selected and used according to the purpose of shading,
Iron oxide black having a particle size of about 1 to 60 μm can be sufficiently used, as long as the conditions such as cost, light resistance, darkness of color, and stability can be satisfied to some extent. In general, with respect to an antiglare sheet obtained by alternately superimposing a light-shielding thin film and a transparent thin film on each other and slicing them in the stacking direction, the thin-cutting thickness W is approximated by the following formula 1.

[0008]

[Equation 1]

In the formula, Ti, γ, and n represent the thickness (hereinafter simply referred to as thickness) in the direction perpendicular to the laminated surface of the transparent thin film, 1/2 visible angle, and the refractive index of the transparent thin film.
Therefore, if the visible angle 2J is determined, the thin-cutting thickness W and the thickness Ti of the transparent thin film can be arbitrarily set within a physically and mechanically possible range.

With respect to the antiglare sheet according to the present invention, the light transmittance thereof can be adjusted within an arbitrary range by the ratio of the thickness of the transparent thin film and the light shielding thin film, and particularly preferably 5 to 60%. This ratio will also be described with respect to the improvement of visibility during daytime and sunset. When the thickness repeating unit (hereinafter simply referred to as “pitch”) of the transparent thin film and the light shielding thin film is set to 100, the light color portion excluding the transparent color and the dark color is A ratio of 35 to 75 is desirable. This is because the display quality at night as the antiglare sheet is deteriorated as described above, even if the whole is inclined to a dark color at 35 or less and is light at 75 or more.

On the other hand, the light transmittance of the antiglare sheet of the present invention can be adjusted within an arbitrary range by the ratio of the layer thickness of the transparent thin film to the light shielding thin film, but it is particularly preferably 5 to 60%. .. If it exceeds 60%, the ratio of the transparent portion in the antiglare sheet becomes large, and therefore the ratio of the light-shielding thin film must be set small, and the ratio of the light-coloring light-shielding thin film surely becomes smaller. Even if the visibility is good, the visibility will be poor during the daytime and evening hours. Conversely 5
If it is less than%, the light transmittance of the anti-glare sheet itself is reduced even though the visibility during daytime and evening is excellent, so the visibility during illumination at night is poor and the ratio of the transparent thin film is considerably smaller than that of the light-shielding thin film. Therefore, there is a disadvantage of impairing the display quality of the letters, symbols and pictures of the nameplate, that is, easy and clear identification of the displayed information.

To obtain a light-colored light-shielding thin film, a light-colored colorant is dispersed in a transparent or opaque resin, and calender molding, extrusion molding, cast molding, compression molding, or screen printing is performed under appropriate conditions. It may be formed into a thin film by any processing method such as coater printing and spray coating. Similarly, in order to obtain a dark light-shielding thin film, a dark colorant is dispersed in a transparent or opaque resin, and similarly, any desired It may be formed into a thin film by a processing method. The reason why the resin in which the colorant is dispersed is made transparent or opaque is that there is no problem with either as long as the colorant has a sufficiently large hiding power for light. In particular,
A method in which the above-mentioned colorant is dispersed together with a vulcanizing agent in a milky white silicone rubber compound and calender molding is preferable.

[0013]

The light-colored light-shielding thin film and the dark-colored light-shielding thin film thus obtained are alternately superposed and joined with the transparent thin film formed into a thin film by an arbitrary processing method. That is, the dark-color light-shielding thin film is superposed on at least one surface of the transparent thin film, and the dark-color light-shielding thin film is superposed on at least one surface of the light-color light-shielding thin film. On at least one side of the antiglare sheet obtained by, for example, black printing is performed while leaving a display part in a state where a letter is drawn to form a predetermined character, symbol, or pattern. The non-black printed area that absorbs a large amount of incident light from the light-shielding thin-film thin film diffuses the incident light in many directions, and the displayed information has a contrast. It is easily visible to people. Also, during nighttime illumination, the light from the light source passes through all the cross sections of the transparent thin film and exits from the unprinted black portion,
The user recognizes these characters, symbols, and patterns.

It is desirable to use an antiglare sheet in which a dark-color light-shielding thin film is superposed on both sides of a transparent thin film, and a dark-color light-shielding thin film is also superposed on both sides of a light-color light-shielding thin film. Good. In this way, the transparent thin film is partially equivalent to the structure of the conventional antiglare sheet, and the light regulation property is also equal.
In addition, since both sides of the light-colored light-shielding thin film are overlapped with the dark-colored light-shielding thin film, the light-colored portion, which is parallel to the passage direction of the illumination light, is shielded in the dark color, thus minimizing light diffusion. Therefore, the original function of the antiglare sheet is not impaired.

[0015]

EXAMPLES The embodiments of the present invention will be described below, but the present invention is not limited thereto. FIG. 1 (a) is a vertical cross-sectional view showing a process of manufacturing an antiglare sheet according to an embodiment of the present invention. First of all, silicone rubber compound KE971
To 100 parts by weight of Tu (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), 30 parts by weight of a white colorant KE Color-W2 (same as above) and 2 parts by weight of a vulcanizing agent C-2 (same as above) were blended to give a white color. The raw materials for the layers were adjusted. This was fed to an I-type three-roll calender to obtain a sheet having a thickness of 100 μm, and then heated in a hot air vulcanizer (length 5 m) at a speed of 5 m / min at 210 ° C.
The cured white layer 1 was formed by passing it at the set temperature of 1.

Next, the silicone rubber compound KE
971Tu (same as above), 100 parts by weight of black coloring agent KE
35 parts by weight of ColorBB (same as above), vulcanizing agent C-2
(Same as above) 2 parts by weight are blended to prepare a raw material for the black layer,
10 μm on the white layer 1 by the same method as the white layer.
And was cured by the same method to form a black layer 2 which becomes a dark-color light-shielding thin film. Subsequently, 100 parts by weight of the silicone rubber compound KE1571u (same as above) and 2 parts by weight of a vulcanizing agent C-2 (same as above) were mixed to prepare a raw material for the transparent layer, and then a black layer was formed by the same method as described above. It was dispensed on the sheet with No. 2 in a thickness of 80 μm and cured in the same manner to form a transparent layer 3 to be a transparent thin film. Finally, 100 parts by weight of the silicone rubber compound KE971Tu (same as above) was mixed with 35 parts by weight of a black colorant KE ColorBB (same as above) and 1.5 parts by weight of a vulcanizing agent C-8 (same as above) to form a black layer. After adjusting the raw materials for the
The uncured black layer 4 was formed by dispensing with a thickness of μm.

The sheet A thus obtained is cut at regular intervals, and the cured white layer 1 and the uncured black layer 4 are repeatedly stacked and joined so as to be superposed, and then 16
The white layer 1 and the black layer 4 are adhered and cured by heating and pressurizing at 0 ° C. for 30 hours at 5 kg / cm ² . Slice the laminated body for which adhesion and curing has been completed to a thickness of 0.24 mm in the laminating direction,
There was obtained a silicone rubber antiglare sheet 5 in which a white layer 1, a black layer 2, a transparent layer 3 and a black layer 4 were repeatedly arranged.

Next, as shown in FIG. 1 (b), 50 parts by weight of each of the liquid silicone rubbers KE1935A (same as above) and KE1935B (same as above) are placed on opposite sides of one set of the antiglare sheet 5. The mixed adhesive 6 is applied by a coater so that each thickness becomes 20 μm, and a polycarbonate film 7 having a thickness of 300 μm is adhered to both applied surfaces, and the uncured antiglare sheet is adhered in a vacuum box. Applying a force of 10g / cm ² on top,
After depressurizing at 0.1 Torr for 30 seconds to remove air bubbles scattered in each layer of the adhesive 6, the adhesive 6 is cured by heat treatment at 120 ° C. for 2 hours to obtain an antiglare sheet B according to the present invention. It was The light transmittance of the antiglare sheet B in which the polycarbonate film 7 and the antiglare sheet 5 in which the white layer 1, the black layer 2, the transparent layer 3, and the black layer 4 were repeatedly arranged were integrated was 35 (%). ..

The thin section surface of the white layer 1 is provided for the purpose of scattering the external light incident from the viewing side of the user and improving the visibility during the daytime and the evening. The fact that the white layer 1 containing a large amount of the white colorant is extremely advantageous for improving the visibility is also apparent from the fact that the white colorant reflects most of visible light uniformly over the entire region. Moreover, since the hiding power of the white layer 1 against light is increased by adding a large amount of a white colorant, almost no light is transmitted,
Therefore, the scattering of the illumination light on the user side becomes extremely small. Furthermore, since the black layer 2 and the black layer 4 cover both surfaces of the white layer 1 in the stacking direction, this also minimizes the diffusion of light and does not impair the original function of the antiglare sheet.

FIG. 2 shows a structure in which the black layer 2 in FIG. 1B is removed, and FIG. 3 shows the transparent layer 3 after the white layer 1 and the black layer 2 in FIG. , Black layer 4
An antiglare sheet obtained by repeatedly stacking an antiglare sheet to which is added, each showing another embodiment of the present invention in a longitudinal sectional view. If the white layer 1 of the light-colored light-shielding thin film scatters the illumination light on the viewer side, the light-shielding property on the viewer side would be deteriorated. Therefore, the following method was used for confirmation. As a measuring device, digital turbidimeter NDH-100
As shown in FIG. 4, a sample 21 (antiglare sheet according to the present invention) was placed using 1DP (trade name, manufactured by Nippon Denshoku Industries Co., Ltd.). The measuring table is equipped with a mechanism capable of mounting the sample 21 on the holder 22 and rotating the sample 21 and the holder 22, and can measure within a range of ± 75 ° about the normal direction of the sample. In the figure, 23 is a halogen lamp and 24
Is a lens and 25 is an integrating sphere.

FIG. 5 shows the result of measurement of the relative amount of transmitted light when the amount of transmitted light in the direction parallel to the louver is 100 in the antiglare sheet according to the present invention. Was equivalent to. Incidentally, in the illuminated display for an automobile, which is subjected to black character blank printing on the surface of the antiglare sheet of the present invention and further subjected to pear print on it, the white layer in the antiglare sheet is outside light even in the daytime. The information displayed is easily and clearly recognized by the user. When illuminated at night, the black layer in the anti-glare sheet suppressed the diffusion of the illumination light, so the light of letters did not appear on the window glass or the like. In this antiglare sheet, the configuration of the antiglare sheet is such that a dark light-shielding thin film is superposed on at least one surface of a transparent thin film, and a dark light-shielding thin film is superposed on at least one surface of a light-coloring light shielding thin film. As a result, it was possible to significantly improve the visibility during the daytime and the evening time as compared with the case where the conventional antiglare sheet was used, and it was possible to make it suitable without impairing the original function.

[0022]

EFFECTS OF THE INVENTION In the present invention, an antiglare sheet capable of maintaining its original function while significantly improving the visibility during the daytime and dusk by allowing the constituent elements of the antiglare sheet to share the respective roles. Can be provided. More specifically, the role of the transparent thin film is to guide the light of the light source provided at the opposite position of the user side to the user side with the antiglare sheet interposed, and the role of the light-shielding thin film is This is to scatter the light incident from the user side to the user side. Also,
The role of the dark-color light-shielding thin film is to regulate the light of the light source and block the light so as to adjust the visible angle range and the light-shielding angle range as in the conventional antiglare sheet. Further, in the present invention, a dark-colored light-shielding thin film is superposed on at least one surface of the light-colored light-shielding thin film on a surface parallel to the laminating direction of the light-colored light-shielding thin film for the purpose of suppressing diffusion of light from the light source as much as possible. It has a configuration. By changing the color of the colorant used for the light-shielding thin film,
Optimal visibility can be provided to the user, and when used not only industrially, but especially in the interior of a vehicle such as an automobile, misidentification is greatly reduced, which greatly contributes to traffic safety.

[Brief description of drawings]

FIG. 1A is a vertical cross-sectional view of a sheet A which is a repeating unit used in an antiglare sheet according to the present invention, and FIG. 1B is a vertical cross-sectional view of a finished product obtained by sticking a polycarbonate to the sheet A.

FIG. 2 is a longitudinal sectional view showing another embodiment of the antiglare sheet of the present invention.

FIG. 3 is a vertical sectional view showing still another embodiment of the antiglare sheet of the present invention.

FIG. 4 is an explanatory diagram of a light transmittance measuring device used in an example of the present invention.

FIG. 5 is a graph showing the measurement results of the amount of relative transmitted light with respect to the antiglare sheet used in the examples of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 White layer 2 Black layer 3 Transparent layer 4 Black layer 5 Striped pattern sheet 6 Adhesive 7 Polycarbonate film 21 Sample 22 Holder 23 Halogen lamp 24 Lens 25 Integration sphere A Sheet which is a repeating unit of striped sheet B Antiglare according to the present invention Sheet

Claims (1)

[Claims] 1. A striped antiglare sheet obtained by alternately stacking and joining a transparent sheet or film and a multilayer colored or opaque sheet or film, and slicing in a laminating direction to obtain a transparent sheet or A dark colored or opaque sheet or film is superposed on at least one side of the film, and a dark colored or opaque sheet or film is superposed on at least one side of a light colored or opaque sheet or film. An antiglare sheet for an illuminated display body, which is characterized in that