JPS59104602A - Light shielding plate - Google Patents

Abstract

PURPOSE:To obtain a light shielding plate which makes a horizontal incident light transmit efficiently, obstructs a light which is made incident from the diagonal direction, is provided in front of a CRT, etc. and improves a picture contrast, by forming parallel grooves by an equal interval on one surface of a transparent board, and filling the grooves with a light shielding composition. CONSTITUTION:A groove 2 is cut and formed on a glass plate 1 which is transparent and whose surface is flat so that the sum of an interval (a) between grooves and width (b) of the groove is 100-1,000mu, the width (b) of the groove is 50-150mu, and depth (c) of the groove is about the sum of the interval (a) and the width (b). Cutting grinder perticles, etc. are removed by means of ultrasonic washing, etc. so that they are not left in the groove, and thereafter, this glass board is used as a master and Ni plating is executed. A mother is obtained by peeling off the Ni plating. A groove is formed on the surface of a transparent plastic plate by use of this mother. A light shielding plate is obtained by taking out a formed plastic plate and rubbing a coloring (black is desirable) paint, etc. into the groove. In this way, that which is suitable for the front of a display, etc. used especially in the out-doors.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light shielding plate that can transmit horizontally incident light and block obliquely incident light, and when installed in front of an RT or the like, improves the contrast of the image. .

So-called "eaves," Venetian blinds, blinds, and the like are known for transmitting horizontally incident light and blocking obliquely incident light. However, since the eaves form a horizontal protrusion, there is a space problem, and while Venetian blinds and blinds have the advantage of allowing air to pass through, they also have the disadvantage of not being able to prevent dust from coming out.

The above drawbacks can be overcome to some extent by using a light shielding plate obtained by laminating transparent plates and light shielding plates alternately and slicing them thinner than the end of the wood. However, this type of light-shielding plate requires (a) the hassle of laminating and slicing a large number of transparent plates and light-shielding plates to make a large one, and (b) the light-shielding plates cover the front and back sides of the light-shielding plate. Therefore, the pitch of the shading roots and the thickness of the shading plate are constant;
If you try to change the angle of incident light that can be blocked (hereinafter, the angle of incident light is the angle with the normal line of the light shielding plate), it is necessary to change ■the thickness of the transparent plate, ■the slice thickness, and in particular, ■ There is a hassle associated with changing the material.

The present inventor conducted research in view of the above drawbacks of the prior art and found that the above drawbacks can be overcome by providing very fine grooves in a transparent substrate and filling the grooves with a coloring material.

The present invention has been made based on the above facts, and the light shielding plate of the present invention has grooves formed in parallel at equal intervals on one side of a transparent substrate, and the grooves are filled with a light shielding composition. It is characterized by the fact that

The transparent substrate l used in the present invention has high transparency,
Any material that can form grooves may be used, including glass and various transparent plastics.

The transparent substrate l has many grooves on one side thereof. The width of the groove is preferably made as small as possible in order to ensure the transmission efficiency of horizontally incident light through the light shielding plate.

However, it is desirable to make the grooves larger in order to stably form the grooves and ensure the light-shielding effect achieved by filling the light-shielding composition. Considering the above points, SOμm~150μm
, preferably 70 μm to 100 μm. The groove pitch, that is, the groove interval a and the groove width, is 1003 m to 7000 μm, preferably OOμrrL to 500 μm, although it depends on the groove depth as described later. The depth C of the groove is approximately the same as the pitch of the groove, but it is preferable to satisfy the relationship of the incident light.

The grooves, which are formed in parallel at regular intervals to satisfy the above five conditions, are filled with a light-shielding composition to impart light-shielding properties. A dark-colored, preferably black ink or paint can be used as the light-shielding composition, and it is filled into the grooves by an appropriate method and dried.

The light-shielding plate of the present invention has been described above, but when the light-shielding plate of the present invention is intended for a transparent plastic substrate, manufacturing efficiency is good if the light-shielding plate of the present invention is manufactured as follows. The manufacturing methods described below include (11) manufacturing of prototypes, (11) manufacturing of press molds, (i
It consists of approximately nine steps: ii) press molding, and (iv) coloring of the grooves.

Prototype production A transparent glass plate with a flat surface is prepared, and grooves of the width, pitch, and depth described above are created using the "Alchiquier method," which uses a grinding device equipped with a large number of endless wire belts coated with abrasive grains on the surface. Provided by cutting. The thickness of the glass plate is sm~30am, preferably lQTrm~koQr1m
For example, the size is 5QI+OII×5011
m to 30 o III 111 x 300 m, and the material may be soda glass, commonly known as "blue plate glass". After cutting, the abrasive particles accumulated in the grooves of the glass plate are removed by ultrasonic cleaning, and if necessary, the ultrasonic cleaning is preferably carried out in an alkaline detergent solution (for example, Amcor) to also serve as degreasing. After ultrasonic cleaning, water is replaced with IPA and dried.

Nickel plating is performed using the glass plate with the grooves formed in the press mold as a master, and approximately 2III! After performing the above plating, it is peeled off and used as a mother. The mother is on both the mold side and the back side,
It is a good idea to leave the surface exposed.

Press molding: Using the above-mentioned mother, molding is performed on the bottom surface of a transparent plastic plate by hot pressing. Transparent plastic plates include acrylic resin, polycarbonate resin, and acrylic/
Styrene copolymer resin, cellulose propionate resin, cellulose propionate acetyl butyrate resin,
Thickness of styrene resin, vinyl chloride resin, etc./1111+1
-smm, preferably 2a1m to 3 beaks.

The transparent plastic plate preferably has one side matted. The matte side should be on the opposite side from the molding side. Adjust the pressing conditions, initially at room temperature with kiss touch / 0
0℃, then pressure 30% and temperature 100℃~/, J O'
C1 or less, 1Is9Q, lλ0℃~ltO℃, 5skV
At A, t g O'C, and the total molding cycle is qo minutes to 6o minutes. Conditions at tgo°C at SS% are maintained for 5 minutes. The configuration during pressing is preferably in the order of platen (press pressure plate)/cushion paper/mirror plate/resin plate/mold/face plate/cushion paper/platen. Cooling after Bubis is carried out by cooling the platen with water, and when the temperature reaches g□°C, the press pressure is released and the polymer being pressed is taken out and released from the mold, thereby obtaining a transparent plastic plate provided with grooves.

Note that silicone oil may be applied to Venus to facilitate mold release.

Coloring of grooves Coloring of grooves can be carried out by a so-called wiping method in which ink or paint is rubbed in using a squeegee. More preferably, prior to wiping, a transparent plastic plate with grooves is immersed in ink or paint,
The grooves can also be sufficiently filled with ink or paint by capillary action. At this time, it is advisable to mask the back flat surface to prevent ink or paint from adhering to it. The type of ink or paint used for coloring may be any of the oxidative polymerization type, solvent drying type, and ultraviolet curing type.

As described above, a light shielding plate for a transparent plastic substrate can be manufactured. If there is an excess area around the resulting light shielding plate due to the flow of the transparent plastic substrate, it may be cut using a saw blade or shirred.
Alternatively, it may be removed by fusing with a carbon dioxide laser. Using a carbon dioxide laser has the advantage that no scraps are produced during cutting.

The light shielding plate of the present invention described above has a good transmission efficiency for horizontally incident light and can block light incident from an oblique direction, so it can be used for various purposes, especially for CRTs used outdoors,
When applied to the front of the oscilloscope display, it improves the contrast of the screen.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the light shielding plate of the present invention. l...@Φ...e Transparent substrate Ko--e...Fist...Groove ao・・・・・・Groove spacing b@Φ...kai...width of the ditch C...No.----Groove depth θ・・・・・・・・・Incident angle Patent applicant: Dai Nippon Printing Co., Ltd. Agent Patent Attorney Atsumi Konishi :! F1 □l ″′″2

Claims (1)

[Claims] (1) A light-shielding plate having grooves formed in parallel at equal intervals on one side of a transparent substrate, the grooves being filled with a light-shielding composition.