JPH01302204A - Lenticular sheet and production thereof - Google Patents

Abstract

PURPOSE:To obtain the lens sheet having excellent antireflection performance of external light by forming a light diffusion layer of fine ruggedness having a specific roughness coefft. without incorporating a light diffusing agent into the thermoplastic resin of an exit face. CONSTITUTION:Many lens parts 1 made of a semi-cylindrical light transparent resin are disposed in parallel on the incident face of projected images and the thermoplastic resin film 3 is laminated on the exit face. The light diffusing agent is not incorporated into the film 3 and the light diffusion layer consisting of the fine ruggedness having 5<Sm/Rz<25 roughness coefft. (where Sm is the average spacing of the ruggedness; Rz is 10-point average roughness, both of which are in micron) is formed by prescribed rolls on the surface thereof. The ruggedness of the surface is thereby made into the ruggedness of the shape without having roundness. The lens sheet having the excellent antireflection performance of external light is obtd.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a transmission type wrench J with excellent anti-reflection performance for external light.
The present invention relates to Ir,:L sheets and their manufacturing method.

[Conventional technology]

Rear projection screens have traditionally been used as microfilm readers, reader printer screens, camera focus glasses, etc., but recently they have come into the spotlight as large television screens. In general, a transmission-type lenticular screen has a large number of semi-cylindrical lenses arranged in parallel on one side of a transparent plate, and even if the projected image enters from one point, it can produce a bright and clear image from any position on the image output side. The advantage of being able to see the image is that it requires excellent performance such as light diffusion and brightness, but at the very least, it is necessary to suppress the surface gloss of the surface on the religious side and improve the image quality due to reflection on this surface. It is also strongly desired to eliminate the difficulty in viewing. Generally, in order to suppress surface gloss, a method is used to make the surface a finely uneven surface, but until now, the method of Applying a liquid to the base resin, drying and solidifying it to form an uneven surface; ■ Mixing a light diffusing agent into the base resin and extruding it to make the base resin surface uneven; ■ Creating a film containing the light diffusing agent. A common method was to laminate the output surface to form an uneven surface.

However, method (2) involves the step of applying a liquid substance containing a light diffusing agent to a translucent resin plate, so adjusting the amount of application and the thickness of the coating film is complicated and requires a high level of skill. If the coating fails, the expensive translucent resin cannot be used, which inevitably leads to higher costs, and the overall productivity is not necessarily high. Furthermore, in the method (2), a large amount of light diffusing agent must be mixed in order to make the surface uneven, resulting in a disadvantage that the light transmittance decreases and the image becomes dark. In addition, in methods (1) and (2), the light diffusing agent protrudes from the surface on the exit surface side and becomes uneven, but there is a problem that the shape becomes rounded and the antireflection performance becomes insufficient.

[Problems to be solved by the present invention]

An object of the present invention is to provide a transmissive lenticular sheet with excellent antireflection performance against external light and a method for manufacturing the same.

[Means to solve the problem]

As a result of intensive research to solve the above problems, the inventors of the present invention have developed a lenticular sheet having minute irregularities on the surface of the exit surface forming part and a specific roughness coefficient, and a method for manufacturing the same. found that it can be achieved,
We have arrived at the present invention.

That is, in the present invention, a large number of semi-cylindrical lenses made of transparent resin are arranged in parallel on the incident surface of the projected image, and the exit side lens surface is formed in correspondence with the large number of incident surface side lens surfaces formed on the incident surface. In a lenticular sheet in which a thermoplastic resin film is laminated and integrally fixed on the exit surface, the thermoplastic resin film does not contain a light diffusing agent, and the surface of the exit surface forming portion of the lenticular sheet has a roughness coefficient. is 5<[Sm/Rz)<25 (However, Sm is the average interval of unevenness (unit: 2 microns),
Rz is the ten-point average roughness (unit: 2 microns, JIs BO
The present invention relates to a lenticular sheet characterized in that gloss is substantially eliminated by forming a light diffusing layer with fine irregularities as described in 601)), and a method for manufacturing the same.

The present invention will be explained in more detail below.

The present invention relates to a lenticular sheet in which a large number of semi-cylindrical translucent resin lenses are arranged in parallel on the incident surface of a projected image, and a thermoplastic resin film is laminated and integrally fixed on the exit surface. Here, the term "semi-cylindrical" means that the entrance side lens portion 1 in FIG. 1 has a semi-cylindrical or semicylindrical shape.
Transparent resins include, for example, acrylic, polycarbonate,
Refers to thermoplastic resins with good translucency such as cellulose, acetate, fluororesin, and polystyrene.

Note that it is preferable that the transparent resin, which is the raw material for the lens, contains a light diffusing agent. Silicon oxide as a light diffusing agent,
Various silicates, titanium oxide, magnesium oxide, aluminum oxide, calcium carbonate, talc, dolomite, etc. can be used alone or in combination of two or more. The particle size of the light diffusing agent is suitably in the range of 1 to 100 microns, preferably 10 to 30 microns.

In addition, the film used in the present invention is made of a thermoplastic resin that can be bonded to the above-mentioned light-transmitting resin and has good light-transmitting properties, such as acrylic, vinyl chloride, polystyrene, polyethylene, poly-1-propylene, etc., and its thickness As for the diameter, 10 to 200μ, preferably 20 to 100μ is used. Various methods such as T-die extrusion, inflation, casting, and calendering can be used to form a film.

A feature of the present invention is that a large number of semi-cylindrical translucent resin lenses are arranged in parallel on the incident surface of the projected image, and the exit surface is a lenticular sheet in which a thermoplastic resin film is laminated and integrally fixed. The second feature is that the light diffusing agent is not contained, and the surface of the exit surface forming portion is provided with fine irregularities as defined below. When a light diffusing agent is added to a transparent resin, the shape of the surface irregularities becomes rounded and the antireflection performance is insufficient. In the present invention, a thermoplastic resin film that does not substantially contain a light diffusing agent is By supplying the screen to a second roll having an exit surface forming portion with fine irregularities on the surface, a screen with excellent external light reflection prevention performance in which the shape of the irregularities on the surface is not rounded can be obtained. In the present invention, it is necessary to provide the surface of the output surface forming portion with unevenness whose roughness coefficient (Sm/Rz) satisfies the following relationship: 5<(Sm/Rz)<25. Here, Sm is the unevenness. , Rz is the ten-point average roughness (JIS BO601), Sm,
Rz is measured using, for example, a universal surface profile measuring device model 5E-3C manufactured by Koita Research Institute and a roughness analyzer model AY-22. Note that the exit surface forming portion refers to the portion 2 in FIG. However, the surfaces of the non-concentrating portion 5 and the rising portion 6 may further have similar irregularities. In the present invention, the surface roughness coefficient (S m / Rz) is the ratio of the average spacing Sm of rRM7J unevenness and the ten-point average roughness Rz, and as a result of the inventors' experiments, the film surface of the exit surface forming part It was found that by appropriately curing 2, a transmissive lenticular sheet with excellent antireflection performance for external light could be obtained.

That is, in the present invention, the roughness coefficient (S m /
It is necessary to provide unevenness in which [Sm/Rz) is 5<C3m/Rz)<25, and when [Sm/Rz) is smaller than 5, the light diffusivity is excellent but the resolution is poor.
If (S m / Rz ) is larger than 25, there is a drawback that the anti-reflection performance of external light is poor.If the surface roughness coefficient is in the range of 10<C3m/Rz)<20, an even better effect is obtained. can get.

Note that when a light diffusing agent is added to the thermoplastic resin film, the surface of the lenticular sheet is in a state where the light diffusing agent is minutely protruded, but the shape is rounded and the antireflection performance is insufficient. As described above, the present invention uses a thermoplastic resin film that does not contain a light diffusing agent on the exit surface side, and uses a second roll that has an exit surface forming part with fine irregularities on the surface to cover the surface of the thermoplastic resin film. It is characterized by providing a predetermined unevenness that is not rounded. Furthermore, by using a film whose Bickert softening point (JIS K7206A method) is 10°C or more lower than that of the transparent resin, the roughness coefficient of the exit surface forming part is 5 < (Sm/Rz) < 2.
It has been found that it is easy to provide fine irregularities of 5.

The present invention relates to a method for manufacturing a lenticular sheet. That is, in the present invention, a transparent resin is extruded into a sheet through an extrusion molding die, and the lens mold roll on the entrance side is arranged as a first roll, and the mold roll on the exit side is arranged as a second roll. When producing a lenticular sheet by cooling and forming the sheet while sandwiching and pressurizing it, and further cooling it after the third roll, the sheet-like molten transparent resin extruded from the extrusion molding die and the fine particles on the surface are formed. A thermoplastic resin film that can be bonded to the resin and that does not substantially contain a light diffusing agent is supplied between the second roll having the exit surface forming part with unevenness, and the surface of the light-transmitting resin is By laminating the
A method for producing a lenticular sheet, characterized in that a light diffusing layer is formed at the same time, and then the film-laminated resin is cooled between a second roll, a third roll, or between subsequent rolls without being held and pressurized substantially. .

The method of the present invention will be explained with reference to FIG. That is, in the method of the present invention, the transparent resin 4 is extruded into a sheet through the extrusion molding die of the extruder 7, and the lens mold roll on the entrance surface side is transferred to the first roll 9 so that the surface of the exit surface forming part is RAM. In the lenticular sheet of the present invention, an entrance surface and an exit surface are formed on the resin sheet by sandwiching and pressurizing a mold roll on the exit surface side provided with unevenness between a pair of rolls arranged on the second roll 10. In the manufacturing method, first, it is necessary to arrange the lens mold roll on the entrance surface side as a first roll and the mold roll on the exit surface side. Thereby, it is possible to easily form a fine shape on the exit surface side, which is in contact with the mold roll for a long time, and to form fine irregularities on the exit surface forming portion. Further, in the present invention, between the sheet-shaped molten transparent resin 4 extruded from the extrusion molding die 8 and the second roll 10, the sheet-like molten transparent resin 4 is press-bonded to the transparent resin 4 and does not substantially contain a light diffusing agent. Supplying the thermoplastic resin film 3, the transparent resin 4
It is characterized by being laminated on the surface of Here the second
The roll has an exit surface forming portion with fine irregularities on its surface. The shaped film laminated resin is the third
It is cooled after the roll 11. One or more rolls may be installed next to the third roll 11.

At that time, between the second roll 10, the third roll 11, and the subsequent rolls, the film is cooled without being pinched and pressurized.The third roll 11 and subsequent rolls are not mold rolls, so the film is laminated. When the resin is cooled while being held and pressurized, the shape formed between the first roll 9 and the second roll 10 changes.
During the first and subsequent rolls, the sample is cooled without being pinched and pressurized. Although the manufacturing method of the present invention has been described using an apparatus in which the rolls are arranged horizontally as described above, it can be carried out in exactly the same way even when the rolls are arranged vertically.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Examples 1 to 3 and Comparison Examples 1 to 3 An acrylic resin with a Pickert softening point of 106°C is extruded through an extrusion molding die, and the lens mold roll on the entrance side is placed on the first roll and the surface of the exit surface forming part. The mold roll on the exit side, which has fine irregularities, is sandwiched and pressurized between a pair of rolls placed on the second roll, and the film is bonded to the acrylic resin and the second roll.
It was supplied between the rolls. (S
m/Rz) values and the evaluation results of lens performance are shown in Table 1.

In the above Examples and Examples, a light diffusing agent was appropriately added to the acrylic resin in order to improve the light diffusivity.

〔effect〕

The present invention has the configuration as detailed above, and can provide a lenticular sheet with excellent anti-reflection performance for external light, and can also efficiently manufacture such a transmission type lenticular sheet. It has the advantage of

[Brief explanation of the drawing]

FIG. 1 is an enlarged perspective cross-sectional view of the lenticular sheet of the present invention, and FIG. 2 is a conceptual side view showing the method of manufacturing the lenticular sheet of the present invention. 1. Inlet side lens part 2.1ta41 [1 Output surface forming part 3 with unevenness, thermoplastic resin film 4, light-transmitting resin 5, non-light condensing part 6, rising part 7, extruder 8, extrusion molding die 9, first roll 10, second roll 11, third roll.

Claims (2)

[Claims] (1) A lenticular sheet in which a large number of semi-cylindrical translucent resin lenses are arranged in parallel on the incident surface of the projected image, and a thermoplastic resin film is laminated and integrated on the exit surface. Does not contain a light diffusing agent, and the surface of the exit surface forming part of the lenticular sheet has a roughness coefficient Sm/Rz of 5<Sm/Rz<25 (However, Sm is the average interval of unevenness, and Rz is the 10-point average A lenticular sheet characterized by forming a light diffusing layer by providing fine irregularities (roughness). (2) Extrude the transparent resin into a sheet through an extrusion molding die, arrange the lens mold roll on the entrance surface side as the first roll, and arrange the mold roll on the exit surface side as the second roll, and then separate the pair of rolls. When manufacturing a lenticular sheet by shaping it while pressing and cooling it between the third and subsequent rolls,
A sheet-shaped molten transparent resin extruded from an extrusion molding die and a second part having an exit surface forming part with fine irregularities on the surface.
Formation of a sheet by supplying a thermoplastic resin film that can be pressure-bonded to the transparent resin and that does not substantially contain a light diffusing agent between the rolls and laminating it on the surface of the transparent resin. A lenticular product characterized in that lens shaping and light diffusion layer formation are performed simultaneously, and then the film-laminated resin is cooled between a second roll, a third roll, or between subsequent rolls without being held and pressurized substantially. Seat manufacturing method. (3) A lenticular sheet or a method for producing the same according to claim 1 or 2, characterized in that a film whose Bickert softening point is 10° C. or more lower than that of the transparent resin is used.