JPH02280102A - Production of light control plate - Google Patents

Abstract

PURPOSE:To easily allow the selective scattering by the angle of a transparent member and the transmission at only the specific angle by forming a resin compsn. consisting of plural compds. having polymerizable carbon-carbon double bonds in the molecules having a difference in refractive index to a film shape and coating the resin with a film or sheet and irradiating the compsn. with UV rays from the direction of the film or sheet to cure the resin compsn. CONSTITUTION:The resin compsn. consisting of plural mixtures of monomers or oligomers contg. >=1 pieces of polymerizable groups, such as acryloyl group, methacryloyl group, vinyl group, and allyl group, in the molecules is made into the film shape by, for example, application, etc., on a substrate. The surface of the film-shaped compsn. is coated with the transparent film or sheet in tight contact therewith and thereafter, the resin compsn. is irradiated with the UV rays from the direction where the compsn. is coated with the film or sheet to cure the resin compsn. The degree of the scattering or the angle of the selectively scattering incident light can be adjusted by the resin compsn. to be used and the conditions for the irradiation. The selective scattering by the angle of the transparent member and the transmission only at the specific angle are easily executed in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a light control plate that selectively scatters incident light in various angular ranges and a method for manufacturing the same.

<Conventional technology> Conventional transparent bodies made of plastic or glass were only transparent to light from any angle. Therefore, as a material that only transmits light from a specific angle, there is an alignment film cut out from a plastic block made by laminating plastic transparent sheets and opaque sheets alternately, and a checkered or striped film made of photosensitive resin on a transparent substrate. A so-called ``shading plate'', in which a relief with a pattern of ``shading'' was provided on top of which a transparent substrate, etc. was combined, was used for boat fishing. As this light shielding plate, for example, there is one shown in Japanese Patent Laid-Open No. 189439/1983.

<Problems to be Solved by the Invention> The above-described conventional alignment films and light shielding plates have problems in that they are expensive due to complicated manufacturing methods and that the film quality is not uniform.

<Means for Solving the Problems> The present invention is a plastic sheet, and a method for manufacturing a light control plate that selectively scatters incident light in a specific angle range with respect to the sheet, in which the refractive index of each sheet is different. A resin composition consisting of a plurality of compounds having one or more polymerizable carbon-carbon double bonds in a certain molecule is maintained in the form of a film, and the surface of the film is closely covered with a transparent film or sheet. The present invention provides a method for manufacturing a light control board, which comprises curing the resin composition by irradiating the resin composition with ultraviolet rays from the direction in which the film or sheet is coated.

The compound having a polymerizable carbon-carbon double bond used in the method of the present invention is a monomer containing one or more polymerizable groups such as an acryloyl group, a methacryloyl group, a vinyl group, or an allyl group in the molecule. or oligomers such as polyester acrylate, polyol polyacrylate, modified polyol polyacrylate,
Polyfunctional acrylates such as isocyanuric acid skeleton polyacrylate, melamine acrylate, hydantoin skeleton polyacrylate, polybutadiene acrylate, epoxy acrylate, urethane acrylate, methacrylates corresponding to these acrylates, tetrahydrofurfuryl acrylate, ethyl acrylate, etc. Carpitol acrylate, dicyclopentenyloxyethyl acrylate, phenylcarpitol acrylate, nonylphenoxyethyl acrylate, 2-hydroxy-3 phenoxypropyl acrylate, ω-hydroxyhexanoyloxyethyl acrylate, acryloyloxyethyl succinate, acryloyloxyethyl phthalate, tribromphenoxyethyl acrylate, isobornyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, 2.2.3.3-tetrafluoropropyl acrylate and methacrylates corresponding to these monofunctional acrylates, and N ~
Examples include rubinylpyrrolidone triallyl isocyanurate, diethylene glycol bisallyl carbonate, and diarylidene pentaerythritol.

These compounds are used as a mixture.

The resin composition used in the present invention is characterized by the mutual solubility and the difference in refractive index of the plurality of compounds that constitute it, and when a combination with poor compatibility has a large refractive index, The degree of scattering increases, and the angular range of scattered incident light also increases.

In the resin composition of the present invention, a photopolymerization initiator is used as necessary.

Examples of the photopolymerization initiator used as necessary include benzophenone, benzyl, Michler's ketone, and 2-
Chlorothioxanthone, 2,4-diethylthioxanthone, benzoin ethyl ether, jetoxyacetophenone, benzyl dimethyl ketal, 2-hydroxy-2
-Methylpropiophenone, -Hydroxycyclohexylphenylketone, etc.

In the present invention, a light control board is produced by curing the resin composition with ultraviolet rays. During the production, the resin composition is formed into a film by, for example, coating on a substrate, and the surface of the film is coated. The present invention relates to a method for producing a light control board, which comprises closely covering the resin composition with a transparent film or sheet, and then curing the resin composition by irradiating ultraviolet rays from the direction of the film or sheet.

Coating the resin composition used in the present invention on a substrate,
A cured product obtained by forming a film and irradiating it with ultraviolet rays without closely covering the surface with a transparent film or sheet has a preemptive i11 function as a whole, but the surface does not exhibit a light control function. Or, if it develops, a thin layer is formed that is only slightly developed. Therefore, when trying to obtain a high-performance pre-fill plate, there is a limit to its thickness and it has not been possible to make it thinner arbitrarily. The thickness of the region where the above-mentioned light control function is not expressed varies depending on the conditions and is not necessarily constant, but is, for example, up to a depth of about 50 μm from the surface.

By using the method for manufacturing a light control plate of the present invention, a light control function can be expressed from near the surface, and therefore, even a cured product having a thickness of less than about 50 μm can have a light control function. I can do it.

The transparent film or sheet used in the method of the present invention is a transparent film or sheet that does not prevent curing by ultraviolet irradiation, and can be manufactured using known raw materials and by a known method.

For example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-α-olefin copolymer, propylene-butene copolymer, polystyrene, polymethyl methacrylate, methyl methacrylate-styrene copolymer, various Use transparent films or sheets of styrene copolymers, various methyl methacrylate copolymers, polyvinyl chloride, various vinyl chloride copolymers, polyvinylidene chloride, polyethylene terephthalate, various polyester polymers, polycarbonate, polyamide, etc. be able to.

Although the thickness of these transparent films or sheets is not particularly limited, for example, a thickness of 5 to 50 μm can be used.

In the method of the present invention, the transparent film or sheet coated with the cured product can be put to practical use without being peeled off after the resin composition is cured, or it can be used after being peeled off. When removing peeling,
It is desirable that the covering transparent film or sheet be made of a material that is easily peelable from the light control plate obtained by the present invention, and for example, various types of polyethylene or polytetrafluoroethylene can be used.

Ultraviolet rays are irradiated using a mercury lamp or a metal halide lamp, but when a rod-shaped lamp is used, by adjusting the irradiation conditions, the produced sheet-shaped cured product can be irradiated in the long and short axis directions of the light source. It exhibits anisotropy, and scatters light at a specific angle only when the light source is rotated around the long sleeve direction.

In other words, the produced sheet-like cured product has regions with different refractive indexes oriented in a certain direction, and light incident from a specific angle is totally reflected and scattered at the boundaries of the regions with different refractive indexes. considered to be a thing.

The degree of scattering and the angle of selectively scattered incident light are:
It can be adjusted depending on the resin composition and irradiation conditions used, and in particular, by changing the incident angle of ultraviolet rays with respect to the cured sample surface during curing, it is possible to change the angle of incident light that is selectively scattered by the cured sheet.

<Effects of the Invention> By the method of manufacturing the light control plate of the present invention, it is possible to relatively easily achieve selective scattering depending on the angle of the transparent member and transmission only at a specific angle, which was previously impossible, and furthermore, it is possible to make the film thinner. This has the effect of reducing weight and raw material costs.

Although the light control plate of the present invention is a plastic sheet, it can also be used in combination with a glass plate or the like.

These materials are then used to create window materials, vehicles, displays, mirrors,
It can be expected to be used in a variety of fields, such as display boards and greenhouses.

<Examples> The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.

Example! A compound represented by the following structural formula (1) (refractive index rate 1.567)
A resin composition prepared by adding and mixing 50 parts by weight and 3 parts by weight of 2-hydroxy-2-methyl-propiophenone was placed on a glass plate for 60 parts by weight.
It is applied to a thickness of μm, and its surface is closely covered with a 25 μm thick transparent polyethylene film (Sumikasen@F221: manufactured by Sumitomo Chemical Co., Ltd.).

Next, a mercury lamp (lamp: HO45-L31, device: UBO45) of 80 W/cm and lamp length 40c+x was used.
A cured sheet was obtained by irradiating ultraviolet rays for 1 minute at a lamp distance ii [140 cta] using a 2-3B (manufactured by Eye Graphics ■).

Example 2 The same resin composition as in Example 1 was applied onto a glass plate to a thickness of 60 μm, and the surface was covered with a 10 μm thick transparent polyvinylidene chloride film (manufactured by Kureha Kagaku Kogyo ■). It was coated and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a cured sheet.

Comparative Example The same resin composition as in Example 1 was coated on a glass plate to a thickness of 60 μm, and a cured sheet was obtained by irradiating with ultraviolet rays under the same conditions as in Example 1, except that a transparent film was not used. Ta.

(Measurement of Haze Value) The angle dependence of the haze value of the cured sheets obtained in Examples and Comparative Examples was evaluated by the following method.

The total light transmittance and scattered light transmittance of the cured sheets obtained in Examples 1 and 2 were measured using an integrating sphere light transmittance measuring device in accordance with JISK-6714 to determine the haze value.

The test piece was tilted as shown in FIG. 2, and the above values were calculated for each angle.

Example 1. The angular dependence of the haze values of the cured sheets of No. 2 and Comparative Example are represented by ■, ■, and ■ in FIG. 1, respectively.

In addition, in Example 1, the coating film was peeled off, and in Example 2, the covering film was removed.
is the measured value when the coating film is in close contact with the coating without peeling it off.

[Brief explanation of drawings]

FIG. 1 shows the angle dependence of the haze value of the cured sorts obtained in Examples and Comparative Examples. ■ Example 1 ■ Example 2 ■ Comparative example FIG. 2 shows the method of measuring haze value. ■ ・・・ Light control board

Claims (1)

[Claims] In the production of a light control plate that is a plastic sheet and selectively scatters incident light within a specific angular range, one or more polymerizable carbon atoms are added to each molecule with a difference in refractive index. A resin composition consisting of a plurality of compounds having carbon double bonds is maintained in the form of a film, the surface of the film is closely covered with a transparent film or sheet, and then ultraviolet rays are irradiated from the direction in which the film or sheet is coated. A method for producing a light control board, comprising curing the resin composition.