JPH0597482A - Heat ray reflecting glass using holographic diffraction grating - Google Patents

Abstract

PURPOSE:To obtain heat ray reflecting glass capable of very efficiently shielding near IR having 780-2,200nm wavelength in sunbeams by using a holographic diffraction grating layer as a heat ray reflecting layer. CONSTITUTION:At least one or more volume phase type holographic diffraction grating layers 3 for IR reflection with grating spaces ensuring selective reflection of near IR are held between the two transparent glass sheets 1 of laminated glass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-reflecting glass using a holographic diffraction grating, particularly 780 to 2200.
The present invention relates to a heat ray reflective glass that shields sunlight in the near infrared region of nm.

[0002]

2. Description of the Related Art As conventional heat-reflecting glass, for example, automobile technology Vol. 42, No. 9, 1988, P122.
8 to P1229, JP-A-58-9850 and JP-A-54-63185.
In the above-mentioned documents and published patent publications, a basic structure as shown in FIG. 5 is shown as a heat ray reflective glass. These have a structure in which a heat ray reflective film 8 is sandwiched in the middle of the laminated glass 1 with an intermediate film PVB 7 interposed therebetween. This heat ray reflective film is formed on a base film 11 by heat ray reflective metal 1 such as silver.
0 and a transparent dielectric 9 such as TiO ₂ are formed as shown in FIG. The transparent dielectric material is a high-refractive index material, and is used to prevent reflection of a metal in the visible region by a light interference effect. Also, SAE Paper N
o. 910541 discloses an achromatic automobile window glass having a structure of [oxide / nitride / glass] or [oxide / nitride / oxide / glass].

[0003]

However, in the conventional heat ray reflective glass using the first metal thin film, the transmission spectrum is as shown in FIG. 17, and the infrared energy shielding rate of sunlight is Although it is 65%, it is not possible to sharply shield the wavelength range of 800 nm to 1200 nm where the irradiation energy of sunlight is most concentrated in the near infrared region of 780 nm to 2200 nm. This light near 1200 nm is the wavelength that humans feel the hottest (surface, 2
7 (No3) 223-227, (1989), ASHRA
E JOURNAL, 1
January 36-42 (1962)) Inability to sharply shield this wavelength range is a cause of reducing the heat insulating effect. In addition, since the metal thin film is radio wave reflective, when it is used for a window glass of an automobile, for example, there is a problem that a mobile phone cannot be used in the vehicle interior. further,
Although anti-reflection is performed by utilizing light interference, interference colors such as gold appear, and there is a visual problem.

The heat-reflecting glass having a multilayer film of oxide and nitride of the second conventional example has a transmission spectrum as shown in FIG. 18, but 700 nm to 110 as in the first conventional example.
Since the transmittance of 0 nm is gentle and the transmittance in the near infrared region is not so low, the heat insulating effect is small and only 40 to 50% of infrared energy can be shielded.

[0005]

SUMMARY OF THE INVENTION According to the present invention, the holographic diffraction grating is formed to have a grating interval of a size that selectively reflects near infrared rays, and this is used as a heat ray reflective film to form two transparent substrates. It is based on the finding that the above problems can be solved by providing a structure in which an intermediate film is sandwiched between the two.

That is, according to the present invention, at least one or more volume phase type holographic diffraction grating layers for infrared reflection having a grating interval for selectively reflecting near infrared rays are sandwiched between two transparent glasses of laminated glass. The present invention relates to a heat ray reflective glass that shields sunlight in the near infrared region.

The present invention will be described in detail below. Figure 1
FIG. 3 is a diagram showing a heat ray reflective glass of one embodiment of the present invention. First, the structure will be described. Reference numeral 3 is an infrared reflection holographic diffraction grating body, which is sandwiched between transparent substrates 1 such as glass via an intermediate film 2. Depending on the infrared reflection characteristics of the diffraction grating body 3 and the heat insulation performance required for the heat ray reflective glass,
It is possible to use only one diffraction grating body as shown in FIG. 1, or it is possible to use two or more diffraction grating bodies having different diffraction wavelength regions in combination. Although the diffraction grating has a single-layer structure in FIG. 1, if the stability of the diffraction grating is poor by itself, the stability can be improved by including the base film (or sheet) or the cover film (or sheet). Can be improved.

The diffraction grating body is obtained by exposing a photosensitive member with a laser beam. The structure of the photoreceptor is shown in FIG. A photosensitive layer 4 formed of a photosensitive resin is formed on a substrate 5, and the surface is covered with a cover film 6. As the photosensitive resin for forming the photosensitive layer, any one for volume phase hologram can be used, for example, a matrix polymer, one or more kinds of photopolymerizable compounds, a photopolymerization initiator, a sensitizer or Those containing additives such as plasticizers, those containing one or more kinds of photopolymerizable compounds, photopolymerization initiators, additives such as sensitizers and plasticizers can be used. JP-A-2-3082, JP-A-2-8031, US Pat. No. 4,696,876, US Pat. No. 39934.
No. 85, "Recording Materials and Photosensitive Resins", Japan Society for the Promotion of Science, Academic Publishing Center (1979) Nos. 183-188.
Also, the photosensitive resin for forming a volume phase hologram described in “Photopolymer Handbook”, edited by Photopolymer Society, published by Industrial Research Society, pages 444 to 459 can be used. The forming method may be either a dry process or a wet process. It is preferable to use the photosensitive resins described in Japanese Patent Application No. 2-315876 and Japanese Patent Application No. 3-104183. The thickness of the photosensitive layer is 10 μm
It is preferably about 100 μm.

As the substrate 5, besides transparent glass, a sheet or film made of one or more kinds of synthetic organic resins can be used. For example, polyethylene terephthalate, cellulose acetate, polyethylene, polypropylene, polyvinyl butyral, polyvinyl alcohol, polyamide, polycarbonate, PMMA, polyacetate, polyvinylidene chloride, polyurethane, or a fill or sheet made of a composite material thereof can be used. It is preferable to use a sheet or film of transparent glass, polyethylene terephthalate, cellulose acetate, polyamide or the like.

The cover film 6 is used to protect the photosensitive layer and prevent polymerization inhibition by oxygen during exposure, and the materials described as the substrate can be used. Surface treatment may be performed on these base materials and covers in consideration of adhesion to the photosensitive resin and easiness of peeling.

FIG. 3 is a constitutional view of a photosensitive member without using a cover film, which can be used when the resistance of the photosensitive layer is good or when the polymerization inhibition by oxygen is not so great. When the photosensitive resin contains a large amount of matrix polymer, the photosensitive layer can be formed by only the resin as shown in FIG. If the photosensitive resin requires pretreatment, it is treated before exposure.

Next, an exposure method for forming an infrared reflection holographic diffraction grating will be described. When the photosensitive resin is sensitive to light around 500 nm emitted from an argon ion laser or the like, the infrared reflection diffraction grating can be recorded by the exposure method shown in FIGS. In FIG. 7, the photoconductor 1
8 is brought into optical contact with the mirror 16 and the glass block 19 via the matching liquid 17. The laser light 15 from the argon ion laser 12 is expanded by the special filter 13, becomes parallel light by the lens 14, and enters from the side surface of the glass block 19. The incident light is reflected on the surface of the mirror 16, and the holographic diffraction grating is recorded by the standing number generated by the interference between the incident light and the reflected light.
At this time, when the incident angle of the laser is θ, the diffraction center wavelength λ of the obtained diffraction grating can be obtained by the following formula. _{^{λ = (n * · λ 1}} ) / (n 2 - n g 2 + Sin 2 θ) 1/2 n: refractive index n _g of the photosensitive resin: refractive index of the crow blocks (1.52) lambda _1: the oscillation of the laser wavelength

FIG. 8 shows a half mirror 20 without using a mirror.
This is a method in which the laser light 15 is divided by and is made to interfere on the photoconductor 18. With this method, it is possible to record not only an axially symmetric hologram but also an axially asymmetric holographic diffraction grating. If the photosensitive resin is sensitive to light having a longer wavelength than red light by a He-Ne laser or the like, a long wavelength oscillation laser 21 without a glass block as shown in FIGS. 9 and 10 is used. The near-infrared holographic diffraction grating exposure method can be used to obtain a near-infrared diffraction grating by exposure with the laser beam 22. When the incident angle of the laser beam on the photoconductor is θ ′, the diffraction center wavelength λ of the formed grating
Is a value calculated by the following formula. λ = (nλ ₁ ) (n ² -Sin ² θ ′) ^1/2 After exposure, when a photosensitive resin that requires post-treatment is used,
Take appropriate action. If post-processing for broadening the band of the diffracted wavelength is performed, the number of infrared rays that can be reflected increases, so that the heat ray reflection efficiency can be improved. It is preferable that one diffraction grating has a half width of a diffraction peak of 200 nm or more. More preferably, one sheet has a full width at half maximum of a diffraction peak of 2
Combining one or more diffraction gratings of 00 nm or more,
It is preferable that the reflectance sharply rises from a wavelength of about 800 nm to the long wavelength side and has a diffraction efficiency of 70% or more in the wavelength range up to 1200 nm. The holographic diffraction grating thus obtained is laminated with two sheets of glass or transparent resin or one sheet of glass and one sheet of transparent resin through an intermediate film to obtain a heat ray reflective glass as shown in FIG. obtain.

[0014]

[Operation] Next, the operation will be described. By using the holographic diffraction grating as the heat ray reflection film in this way, it is possible to sharply shield the short wavelength part of the sunlight, which has a large irradiation amount in the near infrared region, from any wavelength, improving the heat insulation effect. To do. In addition, a heat ray-reflecting glass that transmits radio waves could be obtained without any coloring that would cause visual problems.

The heat-reflecting glass of the present invention can provide a large heat insulating effect even when used in a building, but is most suitable for a window glass for an automobile. Good heat insulation and almost no coloring is one of the most demanded applications for which visibility is important, such as automobile wind seals. As a result, the comfort of the occupant on the day when sunlight is strongly radiated can be obtained, and the cooling load of the air conditioner can be reduced.
Of course, it is also possible to use a mobile phone inside the vehicle.

[0016]

The present invention will be described with reference to the following examples. Example 1 1 g of polyvinyl carbazole as a photosensitive resin having the following formula

[Chemical 1] (R in the formula represents CH ₂ CH ₂ COOH = CH ₂ ) 1 g of an acrylate monomer represented by 3,3 ′, 4,4′-tetra (t-butylperoxidecarbonyl) benzophenone (BTTB) of 0.08 Using a material consisting of 0.003 g of g, 3, 3'-carbonyl-bis (7-diethylaminocoumarin) (KCD), a film with a thickness of 15 μm was formed on a polyethylene terephthalate sheet, and the surface was coated with polyvinyl alcohol (PVA). The photoconductor was covered. Laser light (wavelength 514.) was applied to this photoreceptor by the near infrared holographic diffraction grating exposure method using the argon laser 12 shown in FIG.
Exposure was carried out so that the incident angle of 5 nm) 15 on the glass block 19 was 20 degrees. Then, the PVA on the surface was peeled off, and development processing was sequentially performed with a mixed solvent of toluene and xylene and n-hexane to obtain an infrared reflection holographic diffraction grating. This diffraction grating was laminated with two pieces of glass via PVB as shown in FIG. 1 to obtain a heat ray reflective glass. FIG. 11 shows the transmission characteristics of the heat ray reflective glass according to this example. This heat-reflecting glass had an infrared energy shielding rate of 70% of sunlight, was not colored visually, and was extremely excellent in transmitting radio waves.

Example 2 1 g of a styrene-monobutyl maleate copolymer as a photosensitive resin, manufactured by SNPE (France) under the trade name Acti
0.5g of cryl CL959, epoxy brand name R manufactured by ACR
82, 0.5 g of a 10: 4 mixture of H3552 and BTTB
A film having a thickness of 60 μm was formed on a polypropylene film by using 0.02 g and KCD of 0.0015 g. The surface was also covered with a polypropylene film, and two types of exposure were performed by the method shown in FIG. 7 with the incident angle of the laser beam having a wavelength of 488 nm to the glass block being 35 degrees and 15 degrees. After the exposure, heat treatment was performed at 80 ° C. for 10 hours to obtain two holographic diffraction grating bodies having different diffraction wavelengths. This diffraction grating was laminated on two transparent polycarbonate substrates via PVB as shown in FIG. 12 to obtain a heat ray reflective glass. Its transmission characteristics are as shown in Fig. 13, which shows that the near-infrared energy of sunlight is 4
It was possible to shield 5%. By using two heat ray reflection holographic diffraction gratings in this way, the wavelength width that can be shielded is widened, and even without using the holographic diffraction grating with high reflection efficiency as in Example 1, a relatively adiabatic effect is achieved. It was possible to obtain a good heat-reflecting glass having a high temperature. Further, as in Example 1, there was no interference color as seen in the conventional heat ray reflective glass and radio waves were well transmitted.

Example 3 10 g of a styrene-monobutyl maleate copolymer as a photosensitive resin, represented by the following formula

[Chemical 2] The tribromophenol acrylate represented by 10
g, BTTB 0.8 g, KCD 0.05 g, 10 μm on polyethylene terephthalate film
To a thickness of 10 μm, and the surface was coated with PVA to obtain a photoreceptor. In the near-infrared holographic diffraction grating exposure method using the argon laser 12 shown in FIG. 8, exposure is performed under two conditions with an argon laser beam 15 of 488 nm so that the incident angle to the glass block becomes 40 degrees and 20 degrees. I did. In FIG. 8, 20 indicates a half mirror.
After that, the PVA on the surface is peeled off, and development is performed with a developer containing acetone and a product name of biscoat 17F (fluorine-based monomer) manufactured by Osaka Organic Chemical Industry Co., Ltd. A reflective holographic diffraction grating was obtained. This diffraction grating is made up of two curved transparent glasses for windshields of automobiles via PVB.
When laminated as shown in (1), cracks did not occur and it was possible to obtain a clean heat ray reflective glass. The obtained heat ray reflective glass was able to shield 60% of sunlight near infrared energy. In addition, it was confirmed that there was no visual coloration and that radio waves were transmitted well. Example 4 The same photosensitive resin as described in Example 3 was used as the photosensitive resin, and 1 was directly applied on the transparent glass used for the window glass substrate.
A film was formed to a thickness of 0 μm. The surface was coated with PVA to form a cover film, which was exposed, developed and fixed in the same manner as in Example 3 to form two types of holographic diffraction grating bodies on the glass substrate. The above-mentioned diffraction grating body was placed inside and the glass substrate was placed outside and laminated through PVB as shown in FIG. 15 to obtain a heat ray reflective glass. Figure 1
As can be seen from FIG. 5, in this embodiment, the heat ray reflective glass can be manufactured with a small number of layers. The heat-reflecting glass thus obtained had the transmission spectrum shown in FIG. 16, and shielded 70% of the near infrared energy of sunlight. In addition, there was almost no coloration visually, and radio waves were well transmitted.

[0019]

As described above, according to the present invention, a holographic diffraction grating layer is applied as a heat ray reflecting layer, and the structure is laminated with two transparent substrates such as glass via an intermediate film. As a result, it is possible to obtain the effect that not only the near-infrared light (wavelength 780 nm to 2200 nm) of sunlight can be shielded very efficiently, but also the heat ray reflective glass that is not visually colored and that also transmits radio waves well can be obtained. It was

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a heat ray reflective glass according to an example of the present invention.

FIG. 2 is a configuration diagram of a photoconductor that records a holographic diffraction grating.

FIG. 3 is a configuration diagram of a photoconductor when a cover film is not used.

FIG. 4 is a configuration diagram of a photoconductor made only of a photosensitive resin containing a matrix polymer.

FIG. 5 is a configuration diagram of a conventional heat ray reflective glass.

FIG. 6 is a configuration diagram of another example of a conventional heat ray reflective glass.

FIG. 7 is an explanatory diagram of an example of a near infrared holographic diffraction grating exposure method using an argon laser.

FIG. 8 is an explanatory diagram of another example of a near infrared holographic diffraction grating exposure method using an argon laser.

FIG. 9 is an explanatory diagram of an example of a near infrared holographic diffraction grating exposure method using a long wavelength oscillation laser.

FIG. 10 is an explanatory diagram of another example of a near infrared holographic diffraction grating exposure method using a long wavelength oscillation laser.

11 is a transmission spectrum diagram of the heat ray reflective glass of Example 1. FIG.

FIG. 12 is a configuration diagram of a heat ray reflective glass of Example 2.

13 is a transmission spectrum diagram of the heat ray reflective glass of Example 2. FIG.

FIG. 14 is a configuration diagram of a heat ray reflective glass of Example 3.

FIG. 15 is a configuration diagram of a heat ray reflective glass of Example 4.

16 is a transmission spectrum diagram of the heat ray reflective glass of Example 4. FIG.

17 is a transmission spectrum diagram of the conventional heat ray reflective glass shown in FIG.

FIG. 18 is a transmission spectrum diagram of another conventional heat ray reflective glass shown in FIG. 6.

[Explanation of symbols]

 1 Transparent Substrate 2 Intermediate Film 3 Holographic Diffraction Grating 4 Photosensitive Resin 5 Base Material 6 Cover Film or Cover Sheet 7 Intermediate Film PVB 8 Heat Reflective Film 9 Transparent Dielectric 10 Heat Reflective Metal 11 Base Film 12 Argon Laser 13 Special Filter 14 Lens 15 Laser light 16 Mirror 17 Matching liquid 18 Photoreceptor 19 Glass block 20 Half mirror 21 Long wavelength oscillation laser 22 Laser light

Claims (1)

[Claims] 1. A volume phase type holographic diffraction grating layer for infrared reflection having a grating interval for selectively reflecting near infrared rays is sandwiched between two transparent glasses of laminated glass. A heat-reflecting glass that shields the characteristic near-infrared sunlight.