JPS59111842A - Functional sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light-transmitting sheet that transmits visible light and reflects infrared rays. More specifically, the present invention relates to a selectively transparent sheet that transmits visible light and reflects near-infrared light to infrared light.

In general, by controlling the thickness of each component thin film in a laminate in which conductive metal thin films such as gold, silver, copper, and various alloys containing these as main components are sandwiched between transparent high refractive index dielectric layers, specific wavelength ranges can be achieved. It is known that it is possible to obtain a material that selectively reflects the rays of light.

In particular, the contact layer, which is transparent in the visible region and selectively reflects infrared wavelengths, can be used as a heat ray reflective film.

It is effective from the point of view of energy saving in houses, use of solar energy, etc. However, energy saving in buildings, houses, etc.
In order to further improve the utilization efficiency in the field of solar energy utilization, it is necessary to improve the visible light part (450nm-700nrn) and the near-infrared part (70nm) in the energy distribution of solar rays.
It is more effective to provide selectivity to the transmission characteristics in the wavelength range (0] nm to 2100 nm). This method greatly reduces the transmission characteristics of the near-infrared rays, which are invisible to the human eye in the solar energy distribution, but there are about 50 degrees of heat rays, and greatly improves the transmission characteristics of the visible rays. is more effective for heat insulation, and does not impair transparency in any way, so it can be applied to various fields without affecting the surrounding environment or safety. Examples of application fields include improving the heat insulation of monitoring windows during high-temperature production, further improving the cooling effect by improving the ability to block solar energy that enters through the windows of buildings, cars, trains, and other vehicles, and heat blocking of transparent food containers. Examples include pipes that improve performance and further improve cold retention effects in frozen and refrigerated showcases. These selective transmission optical interference filters are generally Fabry-Bello filters (Fabr-Bello filters).
y-Perot filter) is well known. This is known as an interference filter in which a transparent dielectric material having a specific optical thickness is sandwiched between opposing semi-transparent mirrors, and only light of a specific wavelength is transmitted. U.S. Patent No. 3,682.528 shows that by applying this Fabry-Bello filter, a selective light transmitting sheet with high transmission characteristics in the visible region and high reflection characteristics in the near-infrared region can be obtained. ing. According to this, for example, as the structure of the substrate/metal layer/dielectric/metal layer/dielectric layer, glass, </Ni /A
g/A+203/Ni 7kg/A, 1203 has a transmittance of 70% or more from 400 nm to 700 nm (reflectance of about 1ocI), 700n
A selective light transmitting laminate having a transmittance of 10% or less from m to 2500 nm and a reflectance of about 90% or more has been obtained.

In the Fapley-Perot filter, the transmission wavelength width can be expanded by reducing the thickness of the metal coating, which is a semi-transparent reflector.
Furthermore, it is known that if the refractive index of a dielectric material that improves transmittance is lowered, the transmitted wavelength width will be narrowed. By calculating the refractive index and thickness of the dielectric material so as to obtain a transmission peak at, for example, 550 nm, and making the metal film sufficiently thin, it is possible to create a filter that has high transmission characteristics in the visible region and good blocking characteristics in the near-infrared region. Can be configured. Conventionally, filters have been mainly used for precision optical applications, and from this point of view, metal compounds such as oxides with stable optical constants and low absorption have been used as transparent dielectrics. However, when used in building windows for energy-saving purposes such as blocking solar energy, it must be applied over a large area, and production on an industrial scale is impossible using conventional metal compounds as transparent dielectrics.

This means that the technology for uniformly covering a large area of the surface of a metal thin film layer with metal oxide or the like is still an incomplete technology.

If the metal oxide film is thin and has a thickness of 50X or less, it is possible to simply form a metal oxide film from the metal film by thermal oxidation, etc.; It can be said that it is impossible to produce a uniformly thick oxide film over a large area on an industrial scale.

We have extensively investigated the application of such structures to energy saving applications such as the use of solar energy.

As a result, by uniformly coating an organic compound with a refractive index of 1.35 to 1.65, it is possible to form a transparent dielectric layer (C) that is optically transparent and has uniform optical properties. We found that it is possible.

However, in the past, organic compounds were not used in optical materials due to their non-uniform optical properties, high optical loss, and lack of long-term stability, so their reliability was poor. There were problems with this point. As a result of further research to overcome the drawbacks of such organic compounds, the present inventors discovered that such drawbacks could be overcome by using a specific organic compound, namely polymethacrylonitrile, in the transparent dielectric layer, and arrived at the present invention. This is what I did.

That is, the present invention provides a metal thin film layer (B) with a thickness of 40χ to 300χ on at least one side of the organic polymer (A) + a thickness of 200χ to 3. The transparent dielectric layer (C) and transparent protective layer (D) of oooX are trapped / (B) / (C) / (B
), or (A) / (B) / (C) /
This functional sheet is formed by laminating layers in the order of (B) and (D), and is characterized in that the transparent dielectric layer (C) is made of polymethacrylonitrile.

The organic polymer film (A) referred to in the present invention does not need to be particularly limited, but for the purpose of applying the laminate of the present invention to a transparent window etc., the transmittance at 550 mμ is at least 50. % or more, preferably 75% or more, and any conventionally known organic polymer film (A) that satisfies this condition may be used, but among them, polyethylene terephthalate film , polycarbonate film, polypropylene film, polyethylene film.

Polyethylene naphthalate film, polysulfone film, polyethersulfone film.

Nylon films and the like are preferred, and polyethylene terephthalate films are particularly preferred.

Furthermore, it is within the scope of the present invention to include a coloring agent, an ultraviolet absorber, two dyes, etc. in such an amount as not to impair the mechanical properties and optical properties of the organic polymer film. As a combined film, there is nothing wrong with it.

The metal thin film layer (B) used in the laminate of the present invention may be made of any metal or alloy as long as it has low absorption loss in the visible light region and has high electrical conductivity, but silver is particularly preferred. It is preferable to use it as an ingredient. Other metals that can be included are preferably gold, copper, aluminum, etc., but if the content is significant enough to degrade the properties of silver,
It does not matter what kind of metal it contains. The content of silver is an important factor governing the optical properties of the resulting laminate, and it is preferably contained at least 40% by weight, preferably 50% by weight or more.

In addition, in order to obtain a laminate with particularly high infrared reflectivity, gold, silver,
Preferably, the metal thin film layer (B) is an alloy of two or three metals selected from the three elements copper, or a single metal thin film layer (B) of these metals.

The thickness of the metal thin film layer (B) is not particularly limited as long as it satisfies the required optical properties of the obtained laminate, but in order to have infrared light reflective ability or electrical conductivity, , it is necessary to have continuity as a film in at least a certain area. The thickness at which the metal thin film changes from an island-like structure to a continuous structure is preferably about 30X or more, and preferably 300X or less in order to improve visible light transmission characteristics, which is the object of the present invention.

In order for the laminate to have sufficient visible light transmittance and sufficient infrared light reflectance, it is particularly preferable that the thickness of the gold RW film layer (B) is about 40K or more and about 120X or less.

The metal thin film layer (B) can be formed by any conventionally known method in addition to vacuum evaporation, cathode sputtering, ion blating, etc.
20. In order to form a stable film with a thickness of X or less, a film forming method using high energy particles such as cantos battering method or ion blating method is preferred. In particular, when obtaining an alloy thin film, the cathode sputtering method is preferred from the viewpoint of uniformity of the alloy composition of the formed thin film and uniformity of the thickness of the formed thin film.

Further, when forming the metal thin film layer (B), the material that will become the substrate can be pretreated by a known method in order to stabilize the thin metal layer. These methods include, for example, a leaning treatment such as ion bombardment, an undercoating treatment such as coating with an organic silicate, an organic titanate, an organic zirconate compound, and/or a metal N++ T+,
There is a nucleation stabilization treatment in which S++Bi, Zr, V, Ta, etc. and oxides of these metals are formed in advance by sputtering, etc., and they can be appropriately selected and used within a range that does not adversely affect the optical properties of the laminate. Just do it. If these pre-treatments involve an increase in thickness, the thickness is preferably 100X or less. A treatment similar to this pre-treatment may be performed on the metal layer as a post-treatment.

As the organic compound used in the transparent dielectric layer (C) of the present invention, a homopolymer of polymethacrylonitrile is preferably used.
Copolymers containing mo1% or more can also be preferably used. As such a polymethacrylonitrile copolymer, for example, a polymethacrylonitrile-polystyrene copolymer is preferable.

The method for forming the transparent dielectric layer (C) is to dissolve the resin at an appropriate concentration in a solvent that can dissolve polymethacrylonitrile and its copolymer, and if the area is small, use spin coating, bar coater, doctor knife, etc. It can be obtained by coating and drying.

In the case of large areas, it is possible to form transparent EA dielectric material (C) of any thickness by drying it using a machine such as a gravure roll coater or reverse roll coater. The temperature varies depending on the resin and solvent used, but is usually 80"C to 150C.

In order for the functional sheet of the present invention to optically achieve its purpose, the film thickness of the transparent dielectric layer fc) is from 200χ to 3.
．． It should be between 500x and 1.500x, especially in order to increase the transmittance of visible light.

In particular, the functional sheet of the present invention is exposed to visible light of 550
In order to obtain a laminate having a maximum transmittance in the vicinity of nm, the film thickness of the transparent current-visitor layer (C) should be 1.3 from 600X.
It is particularly preferable that the temperature be between 0.00 K and 0.00 K.

When organic compounds are used for optical purposes like the laminate of the present invention, it is necessary to select a resin with excellent purity and uniformity because the physical properties of the resulting coating control the optical properties of the y-layer. In addition, it is necessary to appropriately select a coating method that can achieve a uniform film thickness. Preferably ±5 of the set film thickness
It is necessary to keep the film thickness within 5 layers.

The laminate of the present invention has a laminate structure (A
) / (B) / (C) / A protective layer (D) can be formed on the outermost layer (B) for the purpose of protecting the (B). Such protection N(1)) protects the laminate of the present invention from mechanical damage.

It has the role of protecting the shrine from infiltration of pollutants such as chemicals and moisture.

In order to achieve this objective and not adversely affect the optical properties of the laminate, the material for the protection M (D) is preferably a material that is optically transparent and has excellent protection ability. Materials for the protective layer (D) that can be used in the present invention include Sl,
A group consisting of inorganic compounds such as oxides such as AI, Tit Zr, and Ta, or mixed oxides of two or three of the above metals, or acrylic resins such as acrylonitrile, polymethacrylonitrile, polymethylmethacrylate, and acrylate resins. Copolymers thereof, resins such as polystyrene resins, vinyl acetate resins, phenoxy resins, polyester resins, and polyurethane resins, and mixtures and copolymers thereof are preferably used as membranes made of organic compounds.

If the usage environment is particularly harsh, a protective layer can be created by laminating polyethylene films, polypropylene films, nylon films, triacetate films, polyester films, polyvinyl butyral sheets, polycarbonate sheets, etc. of various thicknesses using a known method. (
It can also be used as D).

When using a film made of an inorganic compound as a protective N(D), physical forming methods such as sputtering, vacuum evaporation, and ion zonation are preferably used, but a metal alkoxide compound is diluted and coated in an appropriate solvent. The protective layer (D) made of a metal oxide can also be obtained by a known method for forming a metal oxide 'R pattern.

A protective layer C made of an organic compound (when used as a DJ, a protective layer C made of an organic compound is formed by dissolving the above-mentioned resin in a suitable solvent, applying and drying)
D) can be obtained. The protective layer (DJ) in the present invention is not limited to a single layer, but may have a two-layer or three-layer laminated structure.This may be a mutually laminated structure of an inorganic compound and an organic compound, or an organic Laminated structure of mutual compounds.

It may also be a layered structure of inorganic compounds. By using the protective layer (I)l having such a laminated structure, it is possible to obtain a protective layer (DJ) of the laminated body of the present invention having a better protective function.

The thickness of the protective layer (D) of the present invention is not limited as long as it has the ability to protect the laminate;
．． The thickness is preferably 0.05 μm or more, and preferably 50 μm or less, particularly preferably 35 μm or less, in order not to deteriorate the optical properties of the laminate.

The functional sheet of the present invention is used depending on its purpose, but for example, when used for building windows, etc., it can be applied directly to the glass of the window with an adhesive or the like, or it can be applied between double-glazed windows. When used in the windows of automobiles, etc., it can be inserted into laminated glass known as safety glass by a known method via polyvinyl butyral. The functional sheet of the present invention is
When used for such safety glass, it exhibits its properties in particular and can avoid the occurrence of discoloration and smearing.

In this way, the functional sheet of the present invention can be used in an appropriate manner depending on the purpose of use, and can be effectively used not only in controlling the incidence of solar energy but also in all fields of heat radiation prevention. can.

Hereinafter, the present invention will be explained in detail in Examples.

Example 1 A biaxially stretched polyethylene terephthalate film with a thickness of 50 μm was used as a substrate, and a first layer with a thickness of 80 μm was placed on it.
The second layer is a transparent dielectric layer made of polymethacrylonitrile with a thickness of 900x, and the third layer is a silver-copper alloy thin film layer with a thickness of soX (containing 10% copper). A functional sheet was formed containing 10% by weight). The silver-copper alloy thin film layer containing 10% by weight of copper is made by targeting a silver-copper alloy containing 10% by weight of copper using Ar gas pressure 5.
It was formed by DC magnetron sputtering at X 10 Torr.

Input power is 2W/c per unit area of target! Met. The transparent dielectric layer was prepared by dissolving 2 parts of polymethacrylonitrile in a solvent consisting of 1 part of methyl ethyl ketone and 1 part of cyclohexanone, and applying the solution using a bar coater.
Obtained by drying at ℃ for 3 minutes.

The integrated visible light transmittance of the obtained functional sheet (400-7
00nm) is 72cm, and the integrated near-infrared light transmittance (750~2
10 nm) was 28 times.

Example 2 The same functional sheet as in Example 1 was formed except that the silver-copper alloy layer was a metal layer made only of silver.

The metal layer consisting only of silver is formed using Ar using a silver target.
The film thickness of the silver-gold ash layer formed by magnetron sputtering at a gas pressure of 5×10 Torr was 80χ. The obtained functional sheet had an integrated visible light transmittance of 70% and an integrated near-infrared light transmittance of 25 cm.

Example 3 On a biaxially stretched polyethylene terephthalate film with a thickness of 75 μm, a pretreatment layer consisting of an oxide of metal A post-treatment layer consisting of an oxide of metal A functional sheet was obtained by sequentially laminating a silver-copper alloy thin film layer having a thickness of 70A and a post-treatment layer comprising an oxide of metal X having a thickness of 20X.

The silver-copper alloy thin film layer containing 5% by weight of copper was formed in the same manner as in Example 1 by DC magnetron sputtering using a silver-copper alloy containing 5% by weight of copper as a target.

The pre-treatment layer and post-treatment layer made of an oxide of metal
A thin film of gold Ff+X was formed by RF magnetron sputtering using (Sl+Zr, 'I'+) as a target, and then allowed to stand in the air for 10 minutes to naturally oxidize to form an oxide of metal X.

A transparent dielectric layer made of polymethacrylonitrile was provided in the same manner as in Example 1. Table 1 shows the optical properties of the obtained functional sheet.

Table 1 Example 6 A functional sheet was formed in the same manner as in Example 1 except that the gold IF% layer was formed from a silver-gold alloy layer containing 10% by weight of gold. The silver-gold alloy layer contains 10% gold by weight.
Example 1 using a silver-gold alloy target containing wt%
The film thickness of the silver-gold alloy layer formed by the same DC magnetron method was 70X.

The obtained functional sheet had an integrated visible transmittance of 76% and an integrated near-infrared light transmittance of 32%.

A polymethacrylonitrile layer with a thickness of 2 μm was formed as a protective film on this functional sheet. A polymethacrylonitrile layer with a thickness of 2 μm was obtained by applying a solution of 10 M iU of polymethacrylonitrile dissolved in a solvent of 1 part of cyclohexanone and 1 part of methyl ethyl ketone using bar caulk, and drying at 130° C. for 3 minutes. The obtained functional sheet has an integral visible transmittance of 70% and an integral near-infrared light transmittance of 33.
%Met.

Example 7 A thickness of 380μ was applied on both sides of the functional sheet obtained in Example 1.
A polyvinyl butyral sheet of 1.5 mm thick was laminated and then sandwiched between 3 mm thick glass plates. The resulting laminate was held at a temperature of 90°C for 60 minutes at a pressure of 1):477 (yd) to obtain a completely bonded laminated glass structure. The integrated visible light transmittance was 71 points, and the integrated near-infrared light transmittance was 31 points.

Comparative Example 1 The thickness of the second transparent dielectric layer was 1. A functional sheet was formed in the same manner as in Example 1 except that it was formed from a transparent dielectric layer made of o o o X polystyrene.

A transparent dielectric layer made of polystyrene was prepared by adding 2 parts of polystyrene to a solvent of 77 parts of methyl ethyl keto and 3 parts of toluene.
．． After dissolving 5% by weight and coating with a bar coater,
It was obtained by drying at 0°C for 2 minutes.

The obtained functional sheet had an integrated visible light transmittance of 71% and an integrated near-infrared light transmittance of 30%.

This functional sheet was placed into laminated glass in the same manner as in Example 7. Cracks, thought to be caused by the polystyrene layer, were generated over the entire surface of the functional sheet in the obtained laminated glass fc.

Comparative Example 2 A functional sheet was formed in the same manner as in Example 1, except that the second transparent dielectric layer was formed from an acrylate resin with a thickness of 800χ.

The transparent dielectric layer made of acrylate resin was prepared by dissolving 2% by weight of Dianal LR574 (Mitsubishi Rayon KK) in a solvent consisting of 2 parts of methyl isobutyl ketone and 3 parts of methyl ethyl ketone, and coating with a bar coater for 2 minutes at 120' (: Obtained by drying.

The obtained functional sheet had an integrated visible light transmittance of 72% and an integrated near-infrared light transmittance of 30.

This functional sheet was placed in laminated glass in the same manner as in Example 7. Cracks, which were thought to be caused by the acrylate resin layer, were found over the entire surface of the functional sheet in the resulting laminated glass.

Example 8 A biaxially oriented polyethylene terephthalate film having a width of 50 cIn and a thickness of 50 μm was formed into a roll with a length of 5 ounces, and this polyester film was used as a substrate to obtain a large-area laminate of the present invention. That is, a silver-copper thin film layer containing 10% by weight of copper and having a thickness of 90X is formed as a first layer on the polyester film, and a second layer having a thickness of 1.5X is formed on the polyester film. The third layer is a transparent dielectric layer made of polymethacrylonitrile of o o o X, and the fourth layer is a silver-copper thin film layer of 90 mm thick containing 10% by weight of polymethacrylonitrile (500 mm thick). Transparent protective layers consisting of the following were sequentially laminated.

The first and third layers, silver-copper thin film layers containing 10% by weight of copper, were prepared by setting a polyester roll film in a sputtering device that continuously processes roll films.
After exhausting to the pressure of 5 x 10 Ar gas
Torr and maintaining a flow rate of 508 CCM, the first and third layers were formed by DC magnetron sputtering at a film running speed of 10 m/min by applying a DC voltage to a silver-copper alloy containing 10% by weight of copper as a target. Established.

A transparent dielectric layer made of polymethacrylonitrile is prepared by applying a coating solution of polymethacrylate, 1 part of cyclohexanone containing 2% by weight of nitrile, and 2 parts of methyl ethyl ketone to a gravure roll coater using a 300-mesh gravure roll. The drying temperature was 12° C. at a speed of 20 ml/min.

Further, a transparent protective layer made of polymethacrylonitrile was formed using the above-mentioned GRAPHIF O-L coater using a coating solution containing 1 part of cyclohexanone and 2 parts of methyl ethyl ketone containing 1 part of 0.8ffi of polymethacrylonitrile.

A total of 30 samples were sampled from the obtained laminate, 10 samples in the length direction and 3 samples in the width direction, and the optical properties were compared. As a result, the integrated visible light transmittance was 70 ± 2%, and the integrated near-infrared light transmittance was was in the range of 31±2.5, there was almost no difference in color tone, and a laminate having uniform optical properties over a large area was obtained.

Example 9 As the first layer on a polyethylene terephthalate film of JEJ-SA 1100 tt, a metal titanium oil cylinder 2M with a thickness of 2Ox was made of a silver-silk alloy oil cylinder 3M containing 10% by weight of copper with a thickness of soX. A layer consisting of titanium, a transparent dielectric layer made of polymethacrylonitrile with a thickness of 900 as the fourth layer, a metallic titanium layer with a thickness of 20X as the fifth layer, and a copper of 10% by weight with a thickness of soX as the sixth layer.
A functional sheet was obtained by sequentially laminating a silver to copper alloy layer including a silver to copper alloy layer and a layer made of metallic titanium having a thickness of 20× as a seventh layer.

The metallic titanium layer with a thickness of 20X and the silver-copper alloy layer containing 0% by weight of copper with a thickness of 80χ were subjected to DC magnetron sputtering targeting metallic titanium and a silver-copper alloy containing 10% by weight of copper, respectively. Established by law.

At this time, the metal titanium layer/silver-copper alloy layer/metal titanium layer were successively laminated in vacuum.

A transparent dielectric layer made of polymethacrylonitrile was obtained by dissolving polymethacrylonitrile in a solvent consisting of 3 parts of methyl ethyl ketone, 4 parts of cyclohexanone, and 1 part of methyl isobutyl ketone at a double i%, and applying the solution using a bar coater.

The integrated visible light transmittance of the obtained functional sheet was 74%.
The integrated near-infrared light transmittance was 29 coefficients.

This functional sheet was placed in laminated glass in the same manner as in Example 7. No discoloration or cracks that would impair the appearance of the laminated glass were observed.

Patent Applicant Teijin Co., Ltd. Procedural Amendment January 1980/S Japan Special Agency Choyoi'dono 1, Indication of Case Patent Application No. 57-220279 No. 2, Name of Invention Functionality Sea 1-3, Representative of the person making the amendment: Sa Okamoto, Department 4, Agent: 2-1 Uchisaiwai-cho, Chiyoda-ku, Tokyo
No. January 5, Subject of amendment (1) "Reliability" in the first line of page 6 of the specification is corrected to "reliability."

(2) This is one on page 26, line 5 of the specification. "After the,
Supplement the following.

[Example 10 A biaxially stretched polyester film with a thickness of 75μ7n was used as a substrate, and a thin silver film layer with a thickness of 80 μm was formed on it as the first layer, and methacrylonitrile (90 parts) and 2-hydroxy as the second layer. A transparent dielectric layer with a thickness of 800 mm consisting of a copolymer with ethyl methacrylate (410 parts) was added to the third layer.
A thin silver film layer having a thickness of 80 layers was formed.

The first and third silver thin film layers were formed by DC gnetron sputtering at an Ar gas pressure of 5 x 10-'' 1-orr T using lead metal as a target.

The power input to Targetera 1 was 2 W/C per unit area.

The second transparent dielectric layer is made of a copolymer formed from 90 parts of meth)'cryloni-1-lyl and 10 parts of 2-hydroxyethyl methacrylate in a mixed solvent of cyclohexanone-acetone-methylethylke]hen. (Mixing ratio 5:2:
1) was coated with a solution in which the above copolymer was dissolved to a concentration of 2% by weight using a bar coater, and dried at 120° C. for 2 minutes.

The resulting laminate had a visible light transmittance of 76% at a wavelength of 5007 nm and an infrared light reflection rate of 82% at a wavelength of 10 μm.

Furthermore, the integrated visible light transmittance of the laminate normalized by the intensity distribution of solar energy was 72%, and the integrated near-infrared light transmittance was 30%.

A polyvinylbutylene sheet with a thickness of 300 μIn was placed on both sides of the above laminate, and a sheet with a thickness of 3 mm was placed on both sides.
After laminating the float glasses of The visible light transmittance was 71%, and the integrated near-infrared light transmittance was 27%. ” Above-24 (

Claims (1)

[Claims] At least one side of the organic polymer film (A) has a thickness of 4
A metal thin film layer (B) with a thickness of 0X to 300X, a transparent dielectric layer (C) with a thickness of 200X to 3oooX, and a transparent protective layer (D
) is (A) / (B) / (C) / (B),
Or (A) / (B) / (C) / (B) /
A functional sheet formed by laminating layers in the order of (D), characterized in that the transparent dielectric layer (C) is made of polymethacrylonitrile.