JPH03107902A - Composition for light control plate - Google Patents

Abstract

PURPOSE:To obtain the light control plate which selectively scatters only the incident light from a specific angle by combining a compd. which has polymerizable carbon-carbon double bonds in the molecule and a compd. which has no polymerizable carbon-carbon double bonds in the molecule and specifying the difference in refractive index between these compds. CONSTITUTION:The compd. A having the polymerizable carbon-carbon double bonds in the molecule and the compd. B which has no polymerizable carbon- carbon double bonds in the molecule are combined and the difference in the refractive index between the A and the B is specified to be >=0.01. The compd. A which has the polymerizable carbon-carbon double bonds to be used is a monomer or oligomer having >=1 pieces of polymerizable groups, such as acryloyl groups, methacryloyl groups, vinyl groups or allyl groups in the molecule. The compd. B which has no polymerizable carbon-carbon double bonds in the molecule is a compd. which does not contain the polymerizable groups, such as acryloyl groups, methacryloyl groups, vinyl groups or allyl groups in the molecule. The light control plate which selectively scatters only the incident light forming the specific angle and allows the transmission thereof is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a composition for producing a light control plate that selectively scatters only incident light from a specific angle.

<Conventional Technology> Conventionally, the only transparent bodies made of plastic or glass were those that were 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 "light-shielding plate" was commonly used, which has a pattern such as +) - and is further combined with a transparent substrate or the like on top of it. As this light shielding plate, for example, Japanese Patent Laid-Open No. 57-189
There is one shown in Publication No. 439.

<Problems to be Solved by the Invention> However, these conventional alignment films and light shielding plates have problems in that they are expensive due to complicated manufacturing methods, and the film quality is not uniform. In contrast, by curing multiple polymerizable compounds with different refractive indexes under specific ultraviolet curing conditions, it is extremely easy to control light to create a uniform film that selectively scatters only incident light from specific angles. A manufacturing method for obtaining a plate is proposed, for example, in Japanese Patent Application Laid-Open No. 63-309902.

However, this light control plate side resin composition requires a plurality of compounds having one or more polymerizable carbon-carbon double bonds in the molecule, each having a different refractive index.

The present inventor selected only incident light forming a specific angle by combining a compound that has a polymerizable carbon-carbon double bond in its molecule with a compound that does not have a polymerizable carbon-carbon double bond in its molecule. They discovered that a light control plate that scatters and transmits light can be produced, and the present invention was completed.

Means for Solving the Problems> That is, the present invention provides a compound (A) having a polymerizable carbon-carbon double bond in its molecule and a compound (B) having no polymerizable carbon-carbon double bond in its molecule. A combination of (
Provided is a composition for a light control board, characterized in that the difference in refractive index between A) and (B) is 0.01 or more.

The present invention will be explained in detail below.

The compound (A) having a polymerizable carbon-carbon double bond used in 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; It is an oligomer.

For example, polyfunctional acrylates such as polyester acrylate, polyol polyacrylate, modified polyol polyacrylate, isocyanuric acid skeleton polyacrylate, melamine acrylate, hydantoin skeleton polyacrylate, polybutadiene acrylate, epoxy acrylate, urethane acrylate, etc. Methacrylates corresponding to acrylates, as well as tetrahydrofurfuryl acrylate, ethylcarpitol acrylate, dicyclopentynyloxyethyl acrylate, phenylcarpitol acrylate, nonylphenoxyethyl acrylate, 2-hydroxy-8-phenoxypropylacrylate, ω-hydroxy Hexanoyloxyethyl 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-vinylpyrrolidone, triallyl isocyanurate, diethylene glycol bisallyl carbonate, diarylidene pentaerythritol, etc. can be given.

On the other hand, polymerizable carbon-
The compound (B) having no carbon double bond is a compound that does not contain a polymerizable group such as an acryloyl group, a methacryloyl group, a vinyl group, or an allyl group in its molecule. For example, polymers such as polystyrene, polymethyl methacrylate, polyethylene oxide, polyhinylpyrrolidone, polyvinyl alcohol, nylon, toluene, n-hexane, cyclohexane, methyl alcohol, ethyl alcohol acetone, methyl ethyl ketone, tetrahydrofuran, ethyl acetate, dimethyl Examples include organic chemicals such as formamide, dimethylacetamide, and acetonitrile, and plastic additives such as organic halogen compounds, organic silicon compounds, plasticizers, and stabilizers.

The compound (A) having these polymerizable double bonds and the compound (B) having no polymerizable double bonds must be uniformly dissolved in each other before curing, and the compound (A) and (
The difference in refractive index from B) needs to be 0.01 or more, preferably 0.02 or more.

Further, the composition of the compound (A) having a polymerizable double bond and the compound (B) having no polymerizable double bond may be appropriately selected depending on the type of the compound, and is not particularly limited, but is preferably (A) is in the range of 10 to 99% by weight, and (B) is in the range of 90 to 1% by weight, more preferably 50 to 95% by weight and 50 to 5% by weight, respectively.

The composition of the present invention is a photocurable composition for temporary light control production, and when cured with a photocuring device as shown in Figure 1, it selectively scatters incident light at a specific angle. You can create a light control board. In addition, upon curing, the composition is applied onto a substrate or enclosed in a cell, and is irradiated with light from a specific direction to be cured. By this method, it is possible to create a light control plate that selectively scatters incident light at a desired angle.

As the light to be irradiated here, visible light, ultraviolet light, or other light that causes a polymerization reaction is used, and ultraviolet light is particularly preferably used.

A photopolymerization initiator may be appropriately added to the composition as necessary. Examples of the photopolymerization initiator used include benzophenone, benzyl, Michler's ketone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, benzoin ethyl ether, jetoxyacetophenone, benzyl dimethyl ketal, and 2-hydroxy-2-methylpropiophenone. , 1-hydroxycyclohexylphenyl ketone and the like.

The light source used in photopolymerization emits ultraviolet rays, visible light, etc. that contribute to photopolymerization, and the light source has a linear shape when viewed from the irradiated position (film surface).
A rod-shaped lamp is one of the preferred linear illumination sources.

When a linear light source is used and the irradiation conditions are adjusted, the resulting sheet-like cured product exhibits anisotropy in the long and short axis directions of the light source, and only when rotated around the long axis direction of the light source. , scattering light at a specific angle.

That is, in the produced sheet-like cured product, regions having different refractive indexes exist periodically and are oriented in a certain direction. It is thought that light incident from a specific angle is totally reflected and scattered at the boundaries of regions with different refractive indexes.

This region having a different refractive index is a compound (A) having no polymerizable double bond that does not participate in the reaction when the compound (A) having a polymerizable double bond, which is one of the compositions of the present invention, is photocured.
It is thought to be generated by creating a difference in concentration distribution due to the diffusion of B), and it is thought that the larger the difference in refractive index due to the difference in concentration, the higher the light scattering ability of the resulting light control plate. . Therefore, if the difference in refractive index between the respective compounds is less than 0.01, it is considered that they do not have sufficient scattering power because it is difficult to make a difference in refractive index due to a difference in concentration.

<Effects of the Invention> In the composition of the present invention, a light control plate that selectively scatters only incident light at a specific angle, which conventionally required a plurality of polymerizable compounds, can be replaced by a single polymerizable compound. It has become possible to manufacture it by combining it with polymerizable compounds.

Although the light control plate obtained from the composition of the present invention is a plastic sheet, it can also be used by coating a glass plate or other plastic sheet.

These materials are then used to create window materials, vehicles, displays, mirrors,
It can be expected to be used in many fields such as 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. In addition,
In the examples, "parts" means "parts by weight."

Example 1 After dissolving 33 parts of polymethyl methacrylate in 67 parts of N-vinylpyrrolidone, 2-hydroxy-2-methyl-
A resin composition mixed with 3 parts of propiophenone was applied to a glass plate with a thickness of 200 μm, and a distance of 40 cm+ was applied using a 30 W mercury lamp ultraviolet irradiation device as shown in Figure 1.
A cured film was obtained by irradiating ultraviolet rays at n for 1 minute. The dependence of the haze value on the incident light angle was measured as shown in Figure 2. The results are shown in Table-1.

Example 2 A resin composition prepared by dissolving 50 parts of polyvinylpyrrolidone in 100 parts of 2-hydroxyethyl acrylate and then adding and mixing 5 parts of 2-hydroxy-2-methyl-propiophenone was cured in the same manner as in Example 1. A film was obtained and its haze value was measured. The results are shown in Table-1.

Example 3 Acrylate (I) represented by the following structural formula: 1.00 parts J
A cured film was obtained using a composition obtained by adding and mixing 10 parts of dimethylformamide and 3 parts of 2-hydroxy-2-methyl-propiophenone to H2 in the same manner as in Example 1, and its haze value was measured. The results are shown in Table-1.

Comparative Examples 1 to 3 3 parts of 2-hydroxy-2-methyl-propiophenone was added and mixed to 100 parts of each of the acrylates shown in Examples 1 to 3, and each was cured in the same manner as in Example 1. A membrane was obtained. The haze value of each cured film was measured in the same manner as in Example 1. The results are shown in Table-1.

Table-1

[Brief explanation of drawings]

FIG. 1 shows a side view and a plan view of the ultraviolet irradiation device used in Examples and Comparative Examples. Figure 2 shows the method for measuring haze value in Examples and Comparative Examples. Figure-1゜Ultraviolet irradiation equipment diagram-2゜Measurement of haze value

Claims (1)

[Claims] Compounds with polymerizable carbon-carbon double bonds in the molecule (
It is a combination of A) and a compound (B) that does not have a polymerizable carbon-carbon double bond in the molecule, and the refractive index difference between (A) and (B) is 0.01 or more. Characteristic composition for light control board