JPH01128059A - Transmission type screen - Google Patents

Abstract

PURPOSE:To improve impact intensity without deteriorating elastic modulus and failing in rigidity by limiting screen thickness to 0.5-1.5mm and specifying an acrylic resin for the screen base material. CONSTITUTION:The title screen, being composed of the acrylic resin on which a lens plane such as a lenticular lens and a fresnel lens is formed at least on one side, is 0.5-1.5mm in thickness, and for the acrylic resin which is the screen base material, multi-layer structured rubber ingredient whose major ingredient is methylmethacrylate is added 5-25% to the acrylic resin. A dispersing agent can be added to the using acrylic resin to give light diffusivity. Thus the impact intensity durable for practical use can be attained within the range of the specific thickness and the rigidity is not failed when the elastic modulus deterioration is within the tolerance.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transmissive screen used for a projection television screen or the like.

(Prior Art) It has been proposed to manufacture a transmission screen used for the above-mentioned purposes by molding various synthetic resin materials, but the following performance is generally required.

■ High transparency of the medium and high light transmittance, ■ Good moldability such as forming lens surfaces, ■ Good weather resistance, ■ A certain level of heat resistance, and ■ Can withstand printing and painting. , have a certain level of chemical resistance, and ■ have sufficient strength even with a certain level of thin substrate. Considering these performances comprehensively, in practical terms, Acy/L/m fat is used.

(Problems to be Solved by the Invention) One of the few drawbacks of using general acrylic resins is low impact strength.

In particular, in the case of a screen with a lenticular lens on the incident side, as the resolution becomes higher, the pitch of the lenticular lens becomes finer, about 15 to 1 inch. There is a need to make it as thin as possible, and there is an increasing need to maintain strength.

The present invention has been made in view of these circumstances, and its gist is to provide a screen that is made of acrylic resin and has a lens surface such as a lenticular lens or Fresnel lens formed on at least one side. The above acrylic resin, which has a thickness of 15 to 1.5 mm and is a Nuclean base material, has a multilayered rubber component mainly composed of methyl methacrylate, which has a thickness of 5 to 2 mm compared to the acrylic resin.
This is a transmission type screen characterized by the addition of 5%.

(51! Examples) The present invention will be described below with reference to drawings of embodiments.

Figures 1 to 3 each show an example of a transmission type screen according to the present invention, and in Figure vg1, the entrance surface (A) of the base material (1) consisting of one sheet is a Fresnel lens αυ, and the observation surface ( B) shows an example in which a lenticular lens (2) is provided. In addition, Fig. 2 shows a two-piece structure, in which a Fresnel lens a is provided on the observation surface side of one base material (1), and a lenticular lens e1J is provided on the observation surface (B) of the other base material (2). An example is shown below. Furthermore, Figure 3 shows a two-layer structure similar to the example in Figure 2, with one base material (1)
A Fresnel lens αD is provided on the observation surface side of the substrate (2), and a first lenticular lens Qη is provided on the entrance surface side of the other base material (2).
However, the observation surface (B) also shows an example in which a second lenticular lens (A) is provided in the light condensing part and an external light absorption M (C) is provided in the non-light condensing part. In the present invention, in the case of the examples shown in FIGS. 2 and 3, only one of the base materials may have the structure of the present invention and the other may be made of another material, but in particular, it is possible to use a lenticular lens. Preferably, it is applied to a substrate.

The base material constituting the transmission screen of the present invention is an acrylic resin reinforced by adding a rubber component, and the rubber component at this time has a multilayer structure mainly composed of methyl methacrylate. . That is, its multilayer structure includes, for example, a core made of a copolymer of n-butyl acrylate and styrene, and a copolymer of methyl
L/-) and/or methyl acrylate, the core part is a copolymer of methyl methacrylate, styrene and butyl acrylate, and a layer of butyl acrylate and styrene crosslinked is formed on this, and further on this. Examples include those obtained by graft polymerization of methyl methacrylate and/or butyl acrylate. The ratio of such rubber components to acrylic resin is 5 to 5.
When added at 25%, the desired reinforcing effect can be obtained without impairing translucency, and there will be no practical problems even when the screen thickness is made relatively thin at 0.5 to 1.5 wm. . Note that if the amount of the rubber component added is less than 5%, no improvement in impact strength can be expected, and there will be no significant difference from the case without the addition. On the other hand, if it exceeds 25 inches, the elastic modulus and lower rigidity will be insufficient, and furthermore, it will appear yellowish in color and become optically unsuitable.

A diffusing agent can be added to the above acrylic resin in order to impart light diffusivity.

In this case, the additive is El102. CaCO3
Examples include inorganic pigments such as At(0H)3, BaSO4, Al2O2, and other organic pigments.

(Concrete example) The present invention will be further explained below based on specific examples.

Specific example 1 A rubber component in which the core part is a copolymer of n-butyl acrylate and styrene, and a layer formed by graft polymerization of a mixture of methyl methacrylate and butyl acrylate on the outer side is used as Aku IJlv11 resin. The 1δ elastic modulus Note 2) of the specimen obtained by mixing and extrusion molding was measured.

This result is shown in Figure 4, where the elastic modulus without adding any rubber component is s x 1o'97cm'', whereas when 25% is added, it is 1.8
However, this was within 60 inches without addition, and it was confirmed that within this range, deflection due to insufficient rigidity would not be a practical problem.

Note 1) The size of the specimen is 25mm wide. 80m long.

The thickness was 3 mm.

Note 2) The method for measuring the elastic modulus is A8TM D 790
I followed the instructions.

Specific Example 2 A screen was fabricated using the acrylic resin plate (■) produced in Specific Example 1 and the Acrylic IJ/I/ series resin plate (■) produced in the following manner, by press-molding lenticular lenses Note 3) on both sides.

The acrylic resin board ■ has a core made of a copolymer of methyl methacrylate, styrene, and butyl acrylate, and a mixed monomer of butyμ acrylate and styrene is crosslinked on the outside, and a mixed monomer of methyl methacrylate and methyl acrylate is added to the outside. A rubber component graft-polymerized with - was mixed with acrylic lv resin, and the mixture was extruded and manufactured.

When we measured the Dynstadt strengths of the two screens Note 4) ■ and ■ obtained as above, we found that
The results shown in FIG. 5 were obtained. As is clear from this table, the impact strength of the rubber components added at 5% or more was superior to that of the rubber components not added.

In addition, a 1100 x 100 test piece was cut out from the screen manufactured in (■) among the above screens, and the falling ball impact test property was 5.
), the results were as shown in Table 1.

Table 1 Note 3) The pitch of the lenticular lens on the incident side is Im. ! The pitch of the lenticular lenses on the observation side is 1 m.

Note 4) Dynstadt impact strength is -69 for J Engineering S-
The procedure was carried out according to 11.

Note 5) The falling ball impact test was conducted in accordance with J-Tech S-7211, and a 45-ton falling ball was used.

(Effects of the Invention) Since the present invention has the structure as described in detail above, it has impact strength that can withstand practical use within a certain thickness range, and the decrease in elastic modulus is within an allowable range. It has the advantage that it can provide an excellent transmission screen that does not lack rigidity and has comparable optical properties.

[Brief explanation of the drawing]

FIGS. 1 to 3 are partial cross-sectional views showing embodiments of the present invention, and FIGS. 4 and 5 are graphs showing the elastic modulus and dyne-yutt strength in specific embodiments of the present invention. (1), (2)... Base material aDl... Fresnel lens (6), (c)... Lenticular lens tI diagram Tail 2 diagram 3rd concave 1z tendon Tongue //: 7 Renel Shiren ゛12.2122Koleshichiki Erare゛゛Tai 4 Gumu Jyokai Port Kasatsu %

Claims (1)

[Claims] 1. The screen is made of acrylic resin on which a lens surface such as a lenticular lens or Fresnel lens is formed on at least one side, and the screen has a thickness of 0.5 to 1.5 cm.
A transmission screen characterized in that the acrylic resin that is the base material of the screen has a multilayer rubber component containing methyl methacrylate as a main component added in an amount of 5 to 25% based on the acrylic resin. 2. The transmission screen according to claim 1, wherein a light diffusing agent is added to the base material.