TWI540334B - Agent for enhancing visible light quantity transmitting a light permeable substrate and method for producing a highly light permeable substrate - Google Patents

Description

Transmissive visible light amount increasing agent for light-transmitting substrate and manufacturing method of high light-transmitting substrate using the same

The present invention relates to a method for producing a highly transparent substrate characterized in that a visible light amount increasing agent for increasing the amount of visible light transmitted through a light-transmitting substrate and a surface treatment by using the visible light amount increasing agent. And a method of increasing the amount of visible light that penetrates the light-transmitting substrate.

Since the prior art, in order to improve the functionality of an optical element having a function of penetrating light, it is required to improve the light transmittance of the element. For example, in an optical element such as a lens, a glass having a higher transparency is used as a substrate, or an organic polymer film for reducing reflectance is applied to a surface of a substrate. However, the use of a glass having high transparency is problematic in terms of economy, and when an organic polymer film is used, it is difficult to uniformly control the thickness of a very thin film to such an extent that it does not affect the optical characteristics of a lens or the like. In addition, optical components such as solar cells for photovoltaic power generation and optical components such as light-emitting elements of various video devices have functional characteristics that are affected by the amount of transmitted light, and it is necessary to improve light transmission performance to obtain a higher amount of transmitted light, but increase It is more difficult to penetrate a large amount of light.

Japanese Patent Publication No. Sho-50-70040 discloses that the surface of the lens substrate is etched to reduce the reflectance to form fine irregularities having a predetermined pattern. However, the laser light interferes with the etching process. The processing apparatus becomes large-scale, and when there is a curved surface on the lens substrate, it is difficult to form irregularities on the curved surface. Moreover, this method cannot make the amount of increase in the amount of transmitted light more than the amount of decrease in reflected light.

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 50-70040

The present invention has been made in view of the above prior art research, and its object is to increase the visible light penetration amount of the substrate by a simple method which can be used regardless of the material and shape of the substrate.

The object of the present invention can be achieved by forming a layer containing an organic cerium compound and an inorganic cerium compound on the surface of a light-transmitting substrate. The layer can be formed by applying a visible light amount increasing agent of a light-transmitting substrate containing an organic cerium compound and an inorganic cerium compound to a light-transmitting substrate, followed by heat treatment or non-heat treatment. Here, the term "heating treatment" means heating to a temperature exceeding normal temperature (20 to 30 ° C, preferably 25 ° C), and also for outdoor exposure to sunlight for a certain period of time (for example, sometimes reaching 50 to 100). °C). On the other hand, "non-heating treatment" means maintaining a constant temperature at a normal temperature.

The above layer and the above-mentioned penetrating visible light amount increasing agent preferably contain titanium oxide. Further, the titanium oxide is preferably a metal-doped titanium oxide. The titanium oxide may also be titanium peroxide. Further, it is preferable that at least a part of the substrate is made of resin, metal or glass.

The above-mentioned penetrating visible light amount increasing agent preferably contains a thermally decomposable organic compound. In this case, the heat treatment is preferably carried out at a temperature of 400 ° C or higher.

The thermally decomposable organic compound may be a sugar or a sugar alcohol, and the sugar may be at least one selected from the group consisting of a monosaccharide and a disaccharide. On the other hand, the above thermally decomposable organic compound may be a water-soluble organic polymer.

The penetrating visible light amount increasing agent may further comprise a composite selected from the group consisting of (1) a cation, (2) a positively charged conductor or dielectric, and (3) a positively charged conductor and a dielectric or semiconductor. One or two or more positively charged substances in the group.

The penetrating visible light amount increasing agent may further comprise a composite selected from the group consisting of (4) an anion, (5) a negatively charged conductor or dielectric, (6) a negatively charged conductor, and a dielectric or semiconductor, And (7) one or two or more kinds of negatively-charged substances in a group consisting of substances having a photocatalytic function.

The penetrating visible light amount increasing agent may further include the positively charged substance and the negatively charged substance described above.

In the present invention, the term "light" means electromagnetic waves such as ultraviolet light, visible light, or infrared light. Here, "visible light" means electromagnetic waves having a wavelength of 380 nm to 780 nm.

According to the present invention, the amount of visible light transmitted through the light-transmitting substrate can be increased by a simple method regardless of the material and shape of the substrate. Therefore, according to the present invention, a highly light-transmitting substrate can be produced simply and economically. The substrate obtained by the present invention is particularly preferably used as an optical element or an optical member which requires high penetration of electromagnetic waves such as light.

Further, when an organic ruthenium compound and an inorganic ruthenium compound are contained, a visible light amount increasing agent further containing titanium oxide, particularly a metal-doped titanium oxide, is applied onto a light-transmitting substrate and heated. Treating or non-heating treatment, and forming a layer comprising an organic cerium compound and an inorganic cerium compound (preferably further comprising titanium oxide, particularly a metal-doped titanium oxide) on the surface of the light-transmitting substrate When the amount increasing agent further contains a thermally decomposable organic compound, a fine concavo-convex structure is formed on the surface of the layer after heating, and the surface area is increased, and the scattering of light is reduced, so that the amount of visible light is further increased, and the reflection of the translucent substrate is increased. The rate is decreased, which in turn increases the amount of light transmitted through the light-transmitting substrate.

Further, when the above-mentioned penetrating visible light amount increasing agent contains a positively-charged substance and/or a negatively-charged substance, contamination of the surface of the light-transmitting substrate can be prevented, so that the effect of increasing the amount of transmitted light can be maintained for a long period of time.

In general, when the absorption of light by the substrate is excluded, the amount of light passing through the light-transmitting substrate is obtained by subtracting the amount of light reflected on the surface of the light-transmitting substrate from the amount of light incident on the light-transmitting substrate. In other words, the following formula holds: the amount of transmitted light of the light-transmitting substrate = the amount of incident light incident on the light-transmitting substrate - the amount of reflected light of the penetrating substrate.

The present inventors have found that by forming a layer containing an organic cerium compound and an inorganic cerium compound on the surface of a light-transmitting substrate, the amount of visible light transmitted by the light-transmitting substrate unexpectedly exceeds that from the incident to the light-transmitting substrate. The amount of incident light is obtained by subtracting the amount of reflected light of the light-transmitting substrate (and the amount of absorbed light of the substrate), thereby completing the present invention. Further, when titanium oxide is added to the above layer, the amount of transmitted visible light is further increased, and when titanium oxide doped with metal is used as the titanium oxide, the amount of visible light transmitted is further increased.

That is, by implementing the present invention, the amount of visible light transmitted through the light-transmitting substrate increases, and the amount of visible light transmitted through the light-transmitting substrate > the amount of incident visible light incident on the light-transmitting substrate - (reflection of the penetrating substrate) The relationship between the amount of visible light and the amount of absorbed light of the substrate is established.

The increase in the amount of visible light transmitted through the light-transmitting substrate is considered to be due to a layer containing an organic cerium compound and an inorganic cerium compound, a layer containing an organic cerium compound, an inorganic cerium compound, and titanium oxide, or an organic cerium compound, an inorganic cerium compound, and The layer of metal doped titanium oxide itself emits visible light. The reason why the above layer emits visible light is that the atoms or molecules in the layer are excited by electromagnetic waves other than the visible light region such as ultraviolet rays, and when the self-excited state returns to the ground state, visible light is emitted. As described above, a molecule excited by a short-wavelength (higher-energy) electromagnetic wave such as an ultraviolet ray, for example, as a fluorescent light, emits a long-wavelength (lower-energy) electromagnetic wave such as visible light, and has been used in, for example, the field of clothing or papermaking. Established in the field of optical brighteners. In summary, the present invention utilizes a layer comprising an organic cerium compound and an inorganic cerium compound, a layer comprising an organic cerium compound, an inorganic cerium compound and titanium oxide, or a layer comprising an organic cerium compound, an inorganic cerium compound, and a metal-doped titanium oxide layer. Those involved in the visible radiation phenomenon. Further, since it is considered that the positively-charged substance and/or the negatively-charged substance contribute to the visible light radiation phenomenon in some form, it is preferable to contain a positively-charged substance or a negatively-charged substance.

In the present invention, by oxidizing (a) an organic cerium compound and an inorganic cerium compound, (b) an organic cerium compound, an inorganic cerium compound, and titanium oxide, or (c) an organic cerium compound, an inorganic cerium compound, and a doping metal. The penetrating visible light amount increasing agent of the titanium light-transmitting substrate is coated on the light-transmitting substrate, and is subjected to heat treatment or non-heat treatment to form a layer containing an organic germanium compound and an inorganic germanium compound on the light-transmitting substrate. A layer containing an organic cerium compound, an inorganic cerium compound, and titanium oxide, or a layer containing an organic cerium compound, an inorganic cerium compound, and a metal-doped titanium oxide, such that the amount of visible light transmitted increases. That is, the present invention is also a method for producing a highly light-transmitting substrate using the above-described light-transmitting amount increasing agent, or a method for increasing the amount of transmitted visible light using the light-transmitting substrate penetrating the visible light amount increasing agent.

As the substrate to be surface-treated according to the present invention, various light-transmitting substrates can be used. The material of the substrate is not particularly limited, and a hydrophilic or hydrophobic inorganic substrate, an organic substrate, or a combination thereof may be used.

Examples of the inorganic substrate include transparent or translucent glass such as soda lime glass, quartz glass, and heat resistant glass; or a matrix containing a metal oxide such as indium tin oxide (ITO); and ruthenium or a metal. Moreover, as an organic base body, the base body containing a plastic is mentioned, for example. More specifically, examples of the plastic include polyesters such as polyethylene, polypropylene, polycarbonate, acrylic resin, and PET (polyethylene terephthalate); polyamines and ABS. (Acrylonitrile-Butadiene-Styrene Terpolymers, acrylonitrile-butadiene-styrene) resin, thermoplastic resin such as polyvinyl chloride; and polyurethane, melamine resin, urea resin, polyoxyl resin, fluororesin, ring A thermosetting resin such as an oxygen resin. In terms of heat resistance, an inorganic base is preferred, and it is particularly preferred that at least a part or preferably all of them are a base made of a resin, a metal or a glass. Further, as the material of the organic base, a thermosetting resin is preferred.

The shape of the substrate is not particularly limited, and any shape such as a cube, a rectangular parallelepiped, a sphere, a spindle, a sheet, a film, or a fiber may be used. The surface of the substrate may be rendered hydrophilic or hydrophobic by corona discharge treatment or ultraviolet irradiation treatment. The surface of the substrate may also have a flat surface and/or a curved surface, and may also be embossed, but it is preferably smooth.

The penetrating visible light amount increasing agent used in the present invention contains at least a liquid composition of an organic cerium compound and an inorganic cerium compound. The above-mentioned penetrating visible light amount increasing agent preferably further contains titanium oxide, particularly a metal doped titanium oxide.

The term "titanium oxide" as used in the present invention means an oxide of titanium, and examples thereof include various titanium oxides such as TiO, TiO ₂ , TiO ₃ , TiO ₃ /nH ₂ O, titanium oxide, and titanium peroxide. It is a titanium peroxide having a peroxy group. Further, it is preferred that the titanium oxide be in the form of fine particles. The titanium oxide may be amorphous or amorphous in any of amorphous, anatase, brookite, and rutile, but is preferably amorphous, particularly preferably amorphous and anatase. a mixture of mineral types. In the present invention, as the titanium oxide, commercially available sol liquids of various crystal forms of titanium oxide can be used.

The metal contained in the metal-doped titanium oxide is preferably selected from the group consisting of gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum. At least one of the metal elements in the group consisting of palladium, vanadium, niobium, calcium, and barium. As the metal-doped titanium oxide, a commercially available sol solution of various crystal forms of titanium oxide and a sol liquid of various metals can be used.

As the metal-doped titanium oxide, a metal-doped titanium peroxide is particularly preferable. As a method for producing the metal-doped titanium peroxide, a production method based on a hydrochloric acid method or a sulfuric acid method which is a method for producing a normal titanium oxide powder can be employed, and a method for producing various liquid-dispersed titanium oxide solutions can also be employed. Further, the above metal can be combined with titanium peroxide at any stage of production.

The titanium peroxide used in the present invention is preferably amorphous, and particularly preferably a mixture of amorphous titanium peroxide and anatase titanium peroxide.

As a method for producing the above-mentioned metal-doped titanium peroxide, a production method based on a hydrochloric acid method or a sulfuric acid method which is a method for producing a normal titanium oxide powder can be employed, and a method for producing various liquid-dispersed titanium oxide solutions can also be employed. Further, the above metal can be combined with titanium peroxide at any stage of production.

For example, as a specific production method of the above-described metal-doped titanium peroxide, the following first to third production methods and a previously known sol-gel method are exemplified.

First manufacturing method

First, a compound of tetravalent titanium such as titanium tetrachloride is reacted with a base such as ammonia to form titanium hydroxide. Then, the titanium hydroxide is peroxidized with an oxidizing agent to form ultrafine particles of amorphous titanium peroxide. This reaction is preferably carried out in an aqueous medium. Further, it may be converted into anatase-type titanium peroxide by heat treatment arbitrarily. In any of the above steps, gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, niobium, calcium may be mixed. And at least one of hydrazine or such compounds.

The oxidizing agent for peroxidation is not particularly limited, and various types of peroxides, that is, titanium peroxide, which can form titanium peroxide, are preferred, but hydrogen peroxide is preferred. When hydrogen peroxide water is used as the oxidizing agent, the concentration of hydrogen peroxide is not particularly limited, and is preferably from 30 to 40%. It is preferred to cool the titanium hydroxide before performing the peroxidation. The cooling temperature at this time is preferably 1 to 5 °C.

One example of the above first manufacturing method is shown in Fig. 1 . In the illustrated manufacturing method, gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, iron, tin, zinc, antimony, bismuth, antimony, bismuth, antimony, palladium, vanadium, antimony, calcium, and antimony, Alternatively, an aqueous titanium tetrachloride solution and aqueous ammonia are mixed in the presence of at least one of the compounds to form a mixture of the hydroxide of the metal and the hydroxide of titanium. The concentration and temperature of the reaction mixture at this time are not particularly limited, but it is preferably rare and normal temperature. The reaction is a neutralization reaction, and it is preferred to adjust the pH of the reaction mixture to about 7.

The metal and titanium hydroxide obtained by the above method were washed with pure water, cooled to about 5 ° C, and then peroxidized with hydrogen peroxide water. Thereby, an aqueous dispersion containing the amorphous metal-doped perovskite fine particles doped with a metal, that is, an aqueous dispersion containing the metal-doped titanium peroxide can be produced.

Second manufacturing method

The compound of tetravalent titanium such as titanium tetrachloride is oxidized by an oxidizing agent, and then reacted with a base such as ammonia to form ultrafine particles of amorphous titanium peroxide. This reaction is preferably carried out in an aqueous medium. Further, it may be converted into anatase-type titanium peroxide by heat treatment arbitrarily. In any of the above steps, gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, niobium, calcium, and the like may be mixed.钽, or at least one of the compounds.

Third manufacturing method

A compound of tetravalent titanium such as titanium tetrachloride is reacted with an oxidizing agent and a base at the same time, and titanium hydroxide is formed and peroxidized to form ultrafine particles of amorphous titanium peroxide. This reaction is preferably carried out in an aqueous medium. Further, it may be converted into anatase-type titanium peroxide by heat treatment arbitrarily. In any of the above steps, gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, niobium, calcium, and the like may be mixed.钽, or at least one of the compounds.

Further, in the first to third production methods, a mixture of amorphous titanium peroxide and anatase-type titanium peroxide obtained by heating it can be used as a metal-doped titanium peroxide.

Manufacturing method by sol-gel method

A solvent such as water or an alcohol, an acid or a base catalyst is mixed with the titanium alkoxide, and the alkoxide is hydrolyzed to form a superfine sol solution of titanium peroxide. Gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, niobium, calcium, and the like may be mixed at any time before and after the hydrolysis.钽, or at least one of the compounds. Further, the titanium peroxide obtained by the above method is an amorphous type having a peroxy group.

The above titanium alkoxide is preferably a compound represented by the formula: Ti(OR') ₄ (wherein R' is an alkyl group), or one or two alkoxy groups in the above formula (OR' a compound substituted with a carboxyl group or a β-dicarbonyl group, or a mixture thereof.

Specific examples of the aforementioned titanium alkoxide _{include: Ti (O-isoC 3 H} 7) 4, Ti (O-nC 4 H 9) 4, Ti (O-CH 2 CH (C 2 H 5) C 4 H ₉ ) ₄ , Ti(OC ₁₇ H ₃₅ ) ₄ , Ti(O-isoC ₃ H ₇ ) ₂ [CO(CH ₃ )CHCOCH ₃ ] ₂ , Ti(O-nC ₄ H ₉ ) ₂ [OC ₂ H ₄ N(C ₂ H ₄ OH) ₂ ] ₂ , Ti(OH) ₂ [OCH(CH ₃ )COOH] ₂ , Ti(OCH ₂ CH(C ₂ H ₅ )CH(OH)C ₃ H ₇ ) ₄ , Ti (O-nC ₄ H ₉ ) ₂ (OCOC ₁₇ H ₃₅ ) and the like.

Tetravalent titanium compound

As a compound of tetravalent titanium used in the production of a metal-doped titanium peroxide, various titanium compounds can be used as long as a titanium hydroxide which is also called orthotitanic acid (H ₄ TiO ₄ ) can be formed upon reaction with a base. For example, there may be a water-soluble inorganic acid salt of titanium such as titanium tetrachloride, titanium sulfate, titanium nitrate or titanium phosphate. Further, a water-soluble organic acid salt of titanium such as titanium oxalate can also be used. Further, among these various titanium compounds, titanium tetrachloride is preferred because it is particularly excellent in water solubility and the components other than titanium do not remain in the dispersion of the metal-doped titanium peroxide.

Further, when a solution of a compound of tetravalent titanium is used, the concentration of the solution is only in the range of a gel capable of forming titanium hydroxide, and is not particularly limited, but a relatively dilute solution is preferred. Specifically, the solution concentration of the tetravalent titanium compound is preferably from 5 to 0.01% by weight, more preferably from 0.9 to 0.3% by weight.

Base

The base which reacts with the above-mentioned compound of tetravalent titanium may be used as long as it can react with a compound of tetravalent titanium to form titanium hydroxide, and examples thereof include ammonia, caustic soda, sodium carbonate, caustic potash, etc. Good is ammonia.

Further, when the solution of the above base is used, the concentration of the solution is not particularly limited as long as it is within the range of the gel capable of forming titanium hydroxide, and a relatively thin solution is preferred. Specifically, the concentration of the base solution is preferably from 10 to 0.01% by weight, more preferably from 1.0 to 0.1% by weight. Particularly, when ammonia water is used as the base solution, the ammonia concentration is preferably from 10 to 0.01% by weight, more preferably from 1.0 to 0.1% by weight.

Metal compound

As compounds derived from gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, cerium, calcium and cerium, they can be respectively exemplified The following:

Au compound: AuCl, AuCl ₃ , AuOH, Au(OH) ₂ , Au ₂ O, Au ₂ O ₃

Ag compound: AgNO ₃ , AgF, AgClO ₃ , AgOH, Ag(NH ₃ )OH, Ag ₂ SO ₄

Pt compounds: PtCl ₂ , PtO, Pt(NH ₃ )Cl ₂ , PtO ₂ , PtCl ₄ , [Pt(OH) ₆ ] ₂ ^-

Ni compound: Ni(OH) ₂ , NiCl ₂

Co compound: Co(OH)NO ₃ , Co(OH) ₂ , CoSO ₄ , COCl ₂

Cu compound: Cu(OH) ₂ , Cu(NO ₃ ) ₂ , CuSO ₄ , CuCl ₂ , Cu(CH ₃ COO) ₂

Zr compound: Zr(OH) ₃ , ZrCl ₂ , ZrCl ₄

Mn compound: MnNO ₃ , MnSO ₄ , MnCl ₂

Sn _{compound: SnCl 2, SnCl 4, [} Sn (OH)] +

Fe compound: Fe(OH) ₂ , Fe(OH) ₃ , FeCl ₃

Zn compound: Zn(NO ₃ ) ₂ , ZnSO ₄ , ZnCl ₂

Ge compound: GeO, Ge(OH) ₂ , GeCl ₂ , GeH ₄ , GeFe, GeCl ₄

Hf compounds: HfCl ₂ , HfO ₂ , Hf(OH) ₃ ⁺ , HfCl ₄

Y compound: Y ₂ O ₃ , Y(OH) ₃ , YCl ₃

La compound: La ₂ O ₃ , LaCl ₃ , La(OH) ₃

Ce compound: CeO ₃ , Ce(OH) ₃ , CeCl ₃

Pd compound: [Pd(H ₂ O) ₄ ] ²⁺ , PdCl ₂ , PdO ₂

V compound: VCl ₂ , VCl ₄ , VOSO ₄

Nb compound: NbO ₂ , NbF ₄ , NbCl ₄

Ca compound: Ca(OH) ₂ , CaCl ₂ , CaSO ₄

Ta compound: TaF ₃ , TaCl ₃ , TaCl ₄ , TaO ₂

The concentration of titanium peroxide in the aqueous dispersion obtained by the first to third manufacturing methods (including the coexistence of gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum The total amount of ruthenium, osmium, iridium, osmium, palladium, vanadium, niobium, calcium and niobium is preferably from 0.05 to 15% by weight, more preferably from 0.1 to 5% by weight. Further, in the present invention, it is derived from gold, silver, platinum, copper, zirconium, manganese, nickel, cobalt, tin, iron, zinc, lanthanum, cerium, lanthanum, cerium, lanthanum, palladium, vanadium, cerium, calcium, and lanthanum. The blending amount is preferably 1:1 in terms of the molar ratio of titanium to the metal component, and in terms of the stability of the aqueous dispersion, it is preferably 1:0.01 to 1:0.5, more preferably 1: 0.03~1:0.1.

Examples of commercially available titanium peroxide include amorphous amorphous titanium peroxide aqueous dispersion SP185, cerium-doped amorphous titanium peroxide aqueous dispersion SPS185, and copper and zirconium-doped titanium dioxide aqueous dispersion. Liquid Z18-1000 Super A, silver-doped titanium dioxide aqueous dispersion SP-10 (Sustainable Titania Technology).

The penetrating visible light amount increasing agent used in the present invention preferably contains the metal-doped amorphous titanium peroxide obtained by the above method and contains anatase-type titanium peroxide. As the anatase type titanium peroxide, the amorphous titanium peroxide can be converted by heating (typically after coating the surface of the light-transmitting substrate described later), but it is preferably not amorphous. The type of perovskite is converted into anatase type titanium peroxide by heating. That is, the anatase-type titanium peroxide contained in the visible light amount increasing agent may be formed by in-situ formation of a part of the amorphous titanium peroxide by heating, but preferably It is that at least a portion (preferably all) of the anatase type titanium peroxide is additionally added from the outside.

The concentration of the titanium peroxide contained in the visible light amount increasing agent can be appropriately changed depending on the degree of surface treatment of the substrate, and is typically 0.01 to 90% by weight, preferably 0.1 to 50% by weight, more preferably It is 1 to 20% by weight.

When the penetrating visible light amount increasing agent is used for a heat resistant inorganic substrate or a thermosetting resin substrate, it is preferred to contain a thermally decomposable organic compound. The thermally decomposable organic compound is not particularly limited as long as it is an organic compound which is decomposed by heating, and it is preferred to decompose by heating to release a gas such as CO ₂ . The heating temperature is preferably 300 ° C or higher, more preferably 400 ° C or higher, more preferably 450 ° C or higher. The decomposable organic compound may, for example, be a sugar or a sugar alcohol, a water-soluble organic polymer or a mixture thereof, and is preferably a sugar or a sugar alcohol, more preferably a sugar.

Here, the term "sugar" means a carbohydrate having a plurality of hydroxyl groups and a carbonyl group, and examples thereof include monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Examples of the monosaccharide include glucose, fructose, galactose, mannose, ribose, and erythrodose. Examples of the disaccharide include maltose, lactose, and sucrose. Examples of the oligosaccharides include oligofructose and galactooligosaccharide. Examples of the polysaccharide include starch, cellulose, pectin and the like. These may be used singly or as a mixture. From the viewpoint of usability, as the sugar, those having high water solubility are preferred. Therefore, in the present invention, one or a mixture of two or more selected from the group consisting of monosaccharides and disaccharides can be preferably used.

The term "sugar alcohol" refers to the reduction of the carbonyl group of a sugar. Specific examples of the sugar alcohol include erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, maltitol, inositol, and the like. These may be used singly or in the form of a mixture of two or more.

As the "water-soluble organic polymer", any thermally decomposable organic polymer can be used as long as it is water-soluble, and examples thereof include polyethylene glycol, polypropylene glycol, polyethylene glycol-polypropylene glycol block copolymer, and the like. Polyether; polyvinyl alcohol; polyacrylic acid (including base metal salts, ammonium salts, etc.), polymethacrylic acid (including base metal salts, ammonium salts, etc.), polyacrylic acid-polymethacrylic acid (including bases) a salt of a metal salt, an ammonium salt or the like; a polypropylene decylamine; a polyvinylpyrrolidone or the like.

The water-soluble organic polymer may be used singly or as a solubilizing aid for sugars or sugar alcohols, and thus may be formulated together with a sugar or a sugar alcohol. Thereby, the sugar or sugar alcohol can be well dissolved in the penetrating visible light amount increasing agent.

The concentration at which the thermally decomposable organic compound is contained in the above-mentioned visible light amount increasing agent can be appropriately changed depending on the degree of surface treatment of the substrate, and is typically 0.01 to 20% by weight, preferably 0.05 to 15% by weight. More preferably, it is 0.1 to 10% by weight.

Examples of the organic ruthenium compound include various organic decane compounds, and polyfluorene oxides such as polyasoxylated oils, polyoxygenated rubbers, and polyfluorene oxide resins. These may be used singly or as a mixture. As the polyfluorene oxide, those having a decanoic acid alkyl ester structure or a polyether structure in the molecule or having both an alkyl phthalate structure and a polyether structure are preferred. Here, the structure of the alkyl phthalate structure means a structure in which an alkyl group is bonded to a ruthenium atom of a ruthenium skeleton. On the other hand, the term "polyether structure" means a structure having an ether bond, and specific examples thereof include polyethylene oxide, polypropylene oxide, polyoxolane, and polyethylene oxide-polypropylene oxide. The molecular structure such as a block copolymer, a polyethylene-polytetramethylene glycol copolymer, or a polytetramethylene glycol-polypropylene oxide copolymer is not limited thereto. Among them, the polyethylene oxide-polypropylene oxide block copolymer is preferred from the viewpoint of controlling the wettability of the surface of the substrate in accordance with the degree of blockiness and molecular weight thereof.

As the organic cerium compound, particularly preferred is a polyfluorene oxide having both an alkyl phthalate structure and a polyether structure in the molecule. Specifically, it is preferred that the polyether modified polydimethyl methoxyoxane or the like is modified with oxime. It can be produced by a known method, for example, in the synthesis examples 1, 2, 3, and 4 of the Japanese Patent Laid-Open No. Hei-4-242499, or the reference examples of the Japanese Patent Laid-Open Publication No. Hei 9-165318. The method and the like are manufactured. Particularly preferred is a polyethylene oxide-polyepoxy obtained by reacting a two-terminal methallyl polyethylene oxide-polypropylene oxide block copolymer with a dihydrogenated polydimethyloxane. The propane block copolymer is modified with polydimethyl siloxane. Specifically, TSF4445, TSF4446 (GE Toshiba Silicone), KP series (Shin-Etsu Chemical Co., Ltd.), and SH200, SH3746M, DC3PA, ST869A (Dow Corning Toray), and the like can be used.

The concentration of the organic cerium compound in the above-mentioned visible light amount increasing agent can be appropriately changed depending on the degree of surface treatment of the substrate, and is typically 0.01 to 5.0% by weight, preferably 0.05 to 2.0% by weight, more preferably 0.1. ~1.0% by weight.

Examples of the inorganic cerium compound include cerium oxide (cerium oxide), cerium nitride, cerium carbide, decane, and the like, and cerium oxide is preferred. As the cerium oxide, sputum, colloidal cerium oxide, precipitated cerium oxide or the like can be used, and colloidal cerium oxide is preferred. As a commercially available colloidal cerium oxide, for example, PL-1, PL-3 (Fuso Chemical Industry Co., Ltd.) can be used; as the polyphthalate, WM-12 (manufactured by Tama Chemical Industry Co., Ltd.), Silicasol 51 can be used. (Manufactured by COLCOAT).

The concentration of the inorganic cerium compound in the above-mentioned visible light amount increasing agent can be appropriately changed depending on the degree of surface treatment of the substrate, and is typically 0.01 to 98% by weight, preferably 0.1 to 90% by weight, more preferably 10.0. ~80% by weight.

The above-mentioned penetrating visible light amount increasing agent preferably contains water, an alcohol or a mixture of the same, that is, an aqueous medium, or a nonaqueous medium such as an organic solvent. The penetrating visible light amount increasing agent of the present invention preferably contains an aqueous medium in terms of solubility of the thermally decomposable organic compound. The concentration of the medium is typically from 50 to 99.9% by weight, preferably from 60 to 99% by weight, more preferably from 70 to 97% by weight.

The above-mentioned penetrating visible light amount increasing agent is coated on the surface of the light-transmitting substrate to receive a non-heating treatment or a heat treatment. Thereby, a layer containing an organic cerium compound and an inorganic cerium compound is formed on the surface of the light-transmitting substrate, and the amount of visible light transmittance of the light-transmitting substrate is increased. The coating device and the coating method for penetrating the visible light amount increasing agent are not particularly limited, and any apparatus and method can be used. For example, a dipping method, a spray method, a roll coating method, a spin coating method, or a styrofoam coating method can be used. Any arbitrary coating method.

The temperature at the time of heating is not particularly limited, and for example, it can be heated to any temperature of 30 ° C or higher. When it contains a decomposable organic substance, it is more preferably 300 ° C or more, more preferably 400 ° C or more, and more preferably 450 ° C or more. The upper limit of the heating temperature is not particularly limited, but is preferably 1000 ° C or less, more preferably 850 ° C or less, and still more preferably 800 ° C or less in terms of influence on various properties of the substrate. The heating time is not particularly limited as long as the carbonization of the thermally decomposable organic compound can be sufficiently carried out, and is preferably from 1 minute to 3 hours, more preferably from 1 minute to 1 hour, still more preferably from 1 minute to 30 minutes.

When titanium oxide is contained in the visible light amount increasing agent, the titanium oxide is converted into titanium oxide (titanium dioxide) by heating. At this time, the amorphous titanium oxide is further converted into anatase type titanium oxide (generally, the amorphous titanium oxide is converted into an anatase type by heating at 100 ° C for 2 hours or more). Therefore, when the transparent visible light amount increasing agent contains amorphous titanium peroxide, the anatase obtained by the process of amorphous titanium peroxide → amorphous titanium oxide → anatase titanium oxide The type of titanium oxide is present on the surface of the substrate. Further, when the above-mentioned penetrating visible light amount increasing agent already contains anatase type titanium peroxide, the anatase type titanium peroxide is directly converted into anatase type titanium oxide by heating.

When the above-mentioned penetrating visible light amount increasing agent contains a thermally decomposable organic compound, it can be heat-treated by ejecting a decomposition product (carbonic acid gas or the like) derived from a thermally decomposable organic compound that penetrates the visible light amount increasing agent. The surface of the substrate forms a porous layer having a plurality of fine concavities and convexities on the surface. The fineness of the surface of the substrate can be lowered by the fine unevenness, and as a result, the light transmittance of the substrate is further improved. The average layer thickness of the above porous layer is not particularly limited as long as the transmittance of the substrate can be increased, and is preferably 0.1 to 3 μm, more preferably 0.5 to 1 μm, still more preferably 0.1 to 0.5 μm. More preferably, it is 0.05 to 0.3 μm (50 to 300 nm), more preferably 80 to 250 nm, still more preferably 130 to 250 nm, and particularly preferably 130 to 180 nm.

The surface of the porous layer preferably has a surface roughness having a maximum height (Rmax) of 50 nm or less, and the maximum height is more preferably 30 nm or less. The particle diameter of the titanium oxide contained in the porous layer is preferably from 1 nm to 100 nm, more preferably from 1 nm to 50 nm, still more preferably from 1 nm to 20 nm.

In the present invention, fine irregularities are not formed on the surface of the substrate itself by etching treatment or the like, but fine concavities and convexities are formed on the surface of the substrate by forming a thin porous layer on the surface thereof, so that it is not necessary for the substrate itself. Fine processing is performed to easily form irregularities. Further, since the visible light amount increasing agent as the precursor of the porous layer is applied to the surface of the substrate by coating, the surface of the substrate can be treated over a wide range, and even for a substrate having a curved surface like a lens, Concavities and convexities can be easily formed.

Therefore, in the present invention, the simple method of applying the material regardless of the material and shape of the substrate can increase the amount of visible light transmitted through the substrate and reduce the reflectance, thereby providing an increase in the transmittance. A highly transparent substrate with improved optical properties.

In the penetrating visible light amount increasing agent of the present invention, in addition to the above components, various positively-charged substances, negatively-charged substances or a mixture thereof may be formulated. Thereby, contamination of the surface of the substrate can be avoided or reduced, and radical molecules such as oxygen, hydrogen, nitrogen, etc., which become excited states due to the electrons from the anatase-type titanium oxide and/or the bismuth compound, can be restored to the ground state. By the above action, it is possible to prevent the light-transmitting property from being lowered due to the adsorption of the respective radicals and the organic substance in the vicinity of the layer, and it is possible to maintain high light transmittance for a long period of time.

Examples of the positively-charged substance include a cation; a conductor or a dielectric having a positive charge; a composite of a positively-charged conductor and a dielectric or a semiconductor; or a mixture thereof.

The cation is not particularly limited, and is preferably an ion of a base metal such as sodium or potassium; an ion of a base earth metal such as calcium; aluminum, tin, antimony, indium, antimony, selenium, chromium, nickel, antimony, Ions of metal elements such as iron, copper, manganese, tungsten, zirconium, and zinc are particularly preferred as copper ions. Further, a cationic dye such as methyl violet, Bismarck brown, methylene blue or malachite green, or an organic molecule having a cationic group such as polyfluorene modified by a group containing a quaternary nitrogen atom may be used. The valence of the ions is also not particularly limited, and for example, a cation having a valence of 1 to 4 can be used.

As the supply source of the above metal ions, a metal salt can also be used. Specific examples include aluminum chloride, tin dichloride and tin tetrachloride, chromium chloride, nickel chloride, antimony trichloride and antimony pentachloride, iron dichloride and ferric chloride, and antimony chloride. , indium trichloride, antimony trichloride, selenium tetrachloride, copper dichloride, manganese chloride, tungsten tetrachloride, tungsten dichloride, potassium tungstate, zirconium oxychloride, zinc chloride, barium carbonate And various metal salts. Further, a metal hydroxide such as aluminum hydroxide, iron hydroxide, chromium hydroxide or indium hydroxide, a hydroxide such as lanthanum tungstic acid, or an oxide such as a grease oxide may be used.

The conductor or medium having a positive charge may be a conductor or a dielectric other than a cation which generates a positive charge. For example, in terms of durability, the conductor to be used is preferably a metal. For example: aluminum, tin, antimony, indium, antimony, selenium, chromium, nickel, antimony, iron, silver, copper, manganese, platinum, tungsten, zirconium, zinc and other metals or oxidized metals. Further, a composite or alloy of these metals may also be used. The shape of the conductor is not particularly limited, and any shape such as a particle shape, a flake shape, or a fiber shape can be employed.

As the conductor, a metal salt of a part of metal can also be used. Specific examples are: aluminum chloride, tin dichloride and tin tetrachloride, chromium chloride, nickel chloride, antimony trichloride and antimony pentachloride, iron dichloride and ferric chloride, silver nitrate, chlorination Bismuth, indium trichloride, antimony trichloride, selenium tetrachloride, copper dichloride, manganese chloride, platinum tetrachloride, tungsten tetrachloride, tungsten dichloride, potassium tungstate, gold trichloride, Various metal salts such as zirconium oxychloride and zinc chloride. Further, a hydroxide or an oxide such as indium hydroxide or tungstic acid may be used.

Examples of the positively-charged dielectric material include a dielectric material such as wool or nylon which is positively charged by friction.

Next, the principle of imparting a positive charge by the above composite is shown in Fig. 2 . 2 is a conceptual diagram in which a conductor-dielectric or a semiconductor-conductor combination is arranged on the surface of the substrate or a surface layer (not shown). The conductor has a positive charge state on the surface due to the presence of free electrons that are free to move inside at a high concentration. Further, a conductive material containing a cation may be used as the conductor.

On the other hand, the dielectric or semiconductor adjacent to the conductor is dielectrically polarized due to the influence of the surface charge state of the conductor. As a result, a negative charge is generated in the dielectric or semiconductor on the side adjacent to the conductor, and a positive charge is generated in the dielectric or semiconductor on the non-adjacent side. By these actions, the surface of the conductor-dielectric or semiconductor-conductor combination is positively charged while imparting a positive charge to the surface of the substrate. The size of the above composite (referred to as the length through the longest axis of the composite) may be in the range of 1 nm to 100 μm, preferably 1 nm to 10 μm, more preferably 1 nm to 1 μm, still more preferably 1 nm to 100 nm.

The conductor constituting the composite used in the present invention is preferably a metal in terms of durability, and examples thereof include aluminum, tin, antimony, indium, antimony, selenium, chromium, nickel, bismuth, iron, and silver. Copper, manganese, platinum, tungsten, zirconium, zinc and other metals. Further, oxides or composites or alloys of the metals may also be used. The shape of the conductor is not particularly limited, and any shape such as a particle shape, a flake shape, or a fiber shape can be employed.

As the conductor, a metal salt of a part of metal can also be used. Specific examples are: aluminum chloride, tin dichloride and tin tetrachloride, chromium chloride, nickel chloride, antimony trichloride and antimony pentachloride, iron dichloride and ferric chloride, silver nitrate, chlorination Bismuth, indium trichloride, antimony trichloride, selenium tetrachloride, copper dichloride, manganese chloride, platinum tetrachloride, tungsten tetrachloride, tungsten dichloride, potassium tungstate, gold trichloride, Various metal salts such as zirconium oxychloride, zinc chloride, and lithium iron phosphate. Further, a hydroxide of the above-described conductor metal such as aluminum hydroxide, iron hydroxide or chromium hydroxide, or an oxide of the above-mentioned conductor metal such as zinc oxide can also be used.

As the electrical conductor, polyaniline, polypyrrole, polythiophene, polythiophene vinylon, polyisothianaphthene, polyacetylene, polyalkylpyrrole, polyalkylthiophene, polyparaphenylene, polyphenylene vinylon, polymethyl can also be used. Conductive polymers such as oxybenzene, polyphenylene sulfide, polyphenylene ether, polyfluorene, polynaphthalene, polyfluorene, and polyfluorene.

Examples of the semiconductor include C, Si, Ge, Sn, GaAs, Inp, GeN, ZnSe, PbSnTe, and the like, and a semiconductor oxide metal, an optical semiconductor metal, or an optical semiconductor oxide metal can also be used. Preferably, in addition to titanium oxide (TiO ₂ ), ZnO, SrTiOP ₃ , CdS, CdO, CaP, InP, In ₂ O ₃ , CaAs, BaTiO ₃ , K ₂ NbO ₃ , Fe ₂ O ₃ , Ta _{2 are used.} O ₃ , WO ₃ , NiO, Cu ₂ O, SiC, SiO ₂ , MoS ₃ , InSb, RuO ₂ , CeO _{2 ,} etc., are preferably those in which the photocatalytic function is deactivated by using Na or the like.

As the dielectric, can be used as a ferroelectric substance of barium titanate (PZT), so-called SBT, BLT, or below include the PZT, PLZT- (Pb, La) (Zr, Ti) O 3, SBT, _{SBTN-SrBi 2 (Ta, Nb} ) 2 O 3, BST- (Ba, Sr) TiO 3, LSCO- (La, Sr) CoO 3, BLT, BIT- (Bi, La) 4 Ti 3 O 12, BSO- A composite metal such as Bi ₂ SiO ₃ . Further, a decane compound, a polyfluorene oxide compound, a so-called organically modified cerium oxide compound, or an organic polymer insulating film aryl ether polymer, benzocyclobutene or a fluorine-based compound may be used. Various low dielectric materials such as polymer parylene N or F, fluorinated amorphous carbon, and the like.

Next, the mechanism for removing contaminants from the surface of the positively charged substrate is shown in FIG.

First, a positive charge is applied to the surface of the substrate (Fig. 3 (1)).

Contaminants accumulate on the surface of the substrate and are photooxidized by the action of electromagnetic waves such as sunlight. The photooxidation reaction refers to a phenomenon in which hydroxyl radicals (‧OH) and singlet oxygen are generated from moisture (H ₂ O) or oxygen (O ₂ ) on the surface of organic or inorganic substances by the action of electromagnetic waves such as sunlight. When (1O ₂ ), electrons (e-) are taken from the organic or inorganic substance to be oxidized. The molecular structure of an organic substance changes due to the oxidation, and it can be seen as a discoloration or embrittlement phenomenon, and inorganic substances, particularly metals, may rust. The surface of these "oxidized" organic or inorganic substances is positively charged by electrons (e-). Thus, the pollutants are also given a positive charge (Fig. 3 (2)).

A positive repulsion of positive charges is generated between the surface of the substrate and the contaminant, and a repulsive force is generated for the contaminant. Thereby, the adhesion of the pollutant to the surface of the substrate is lowered (Fig. 3 (3)).

The pollutants can be easily removed from the substrate by the physical action of wind and rain (Fig. 3(4)). Thereby, the substrate can be self-cleaned.

As described above, a positive electric charge is imparted to the layer containing the organic cerium compound and the inorganic cerium compound on the surface of the substrate, whereby the positively charged contaminant can be prevented from adhering to the surface of the substrate. However, on the other hand, there are negatively charged substances such as chloride ions in tap water; originally charged with positive charges, but become negatively charged by interaction with other objects (friction, etc.) . Such negatively charged contaminants are readily adsorbed on the surface of a substrate that is only positively charged. Therefore, the above layers may also have a negative charge at the same time. Thereby, it is possible to prevent the contaminant having a negative charge from adhering to the surface of the substrate.

Examples of the negatively-charged substance include an anion; a conductor or a dielectric having a negative charge; a composite of a negatively charged conductor and a dielectric or a semiconductor; a substance having a photocatalytic function; or a mixture thereof .

The anion is not particularly limited, and examples thereof include halide ions such as fluoride ions, chloride ions, and iodide ions; inorganic ions such as hydroxide ions, sulfate ions, nitrate ions, and carbonate ions; and acetate ions. Organic ion. The valence of the ions is also not particularly limited, and for example, an anion having a valence of 1 to 4 can be used.

Examples of the conductor or dielectric having a negative charge include a conductor or a dielectric other than the anion which generates a negative charge, and examples thereof include metals such as gold, silver, and platinum; and graphite, sulfur, and selenium. Ruthenium and other elements; sulfides such as arsenic sulfide, antimony sulfide, sulfurized mercury; clay, glass powder, quartz powder, asbestos, starch, kapok, silk, wool, etc.; Prussian blue, indigo, aniline blue, blush, naphthol yellow, etc. The colloid of the dye. Among these, a colloid of a metal such as gold, silver or platinum is preferred, and a silver colloid is particularly preferred. Further, examples thereof include a negative electrode of a battery including various conductors described above, and a negatively charged dielectric such as Teflon (registered trademark), vinyl chloride, polyethylene, or polyester.

As the semiconductor, the ones described above can be used.

As a substance having a photocatalytic function, a function of containing a specific metal compound and having oxidative decomposition of an organic and/or inorganic compound on the surface of the layer by photoexcitation can be used. The photocatalytic principle is generally understood to: the particular compound of a metal generated by photoexcitation OH from the water in the air or oxygen ^- ₂ or O ^- radical species of the radical species to the reductive decomposition of an organic and / or inorganic oxide compounds.

As the above metal compound, in addition to the representative titanium oxide (TiO ₂ ), ZnO, SrTiOP ₃ , CdS, CdO, CaP, InP, In ₂ O ₃ , CaAs, BaTiO ₃ , K ₂ NbO ₃ , Fe _{2 are known.} O ₃ , Ta ₂ O ₅ , WO ₃ , NiO, Cu ₂ O, SiC, SiO ₂ , MoS ₃ , InSb, RuO ₂ , CeO _{2 ,} and the like.

A substance having a photocatalytic function may also contain a metal (Ag, Pt) which enhances photocatalytic properties. Further, various substances such as metal salts can be contained within a range that does not deactivate the photocatalyst function. Examples of the metal salt include metal salts of aluminum, tin, chromium, nickel, ruthenium, iron, silver, iridium, indium, bismuth, selenium, copper, manganese, calcium, platinum, tungsten, zirconium, zinc, and the like. A part of the metal or non-metal, etc., may also use a hydroxide or an oxide. Specific examples are: aluminum chloride, tin dichloride and tin tetrachloride, chromium chloride, nickel chloride, antimony trichloride and antimony pentachloride, iron dichloride and ferric chloride, silver nitrate, chlorination Bismuth, indium trichloride, antimony trichloride, selenium tetrachloride, copper dichloride, manganese chloride, calcium chloride, platinum tetrachloride, tungsten tetrachloride, tungsten dichloride, potassium tungstate, three Various metal salts such as gold chloride, zirconium oxychloride, and zinc chloride. Further, examples of the compound other than the metal salt include indium hydroxide, decyl tungstic acid, cerium oxide sol, and calcium hydroxide.

In the excited state, the material having the photocatalytic function adsorbs OH ^- (hydrogen peroxide radical) and O ₂ ^- (oxidized radical) from the physical adsorption water or oxygen of the surface of the material, and has an anionic property on the surface, but When a positively-charged substance is allowed to coexist thereon, the photocatalytic activity is lowered or lost depending on the concentration ratio. However, in the present invention, a substance having a photocatalytic function does not need to be oxidatively decomposed by a contaminant, and thus can be used as a negatively charged substance.

The surface of the negatively charged substrate is the same as that of the positively charged substrate shown in Fig. 3. The electrostatic repulsion of the negatively charged contaminant prevents the contaminant from adhering to the surface of the substrate.

On the other hand, among the pollutants, there is a person who has a positive charge but becomes a negatively charged by interaction with other objects (friction or the like). Such contaminants with positive and negative charges are easily adsorbed on the surface of a substrate with only a single charge. Therefore, in this case, by imparting positive and negative charges to the substrate, it is possible to prevent such contaminants from adhering to the surface of the substrate.

For example, for polluting substances having both positive and negative charges such as pollen, by attaching both positively charged substances and negatively charged substances to the penetrating visible light amount increasing agent of the present invention, adhesion of such pollutants can be avoided or reduced. On the substrate. For example, on the surface of a substrate having a positive charge and a negative charge, a pollution-inducing substance having a negative charge or an amphoteric charge such as a yellow sand or kaolin clay fine powder, an algal fungus or a pollen, or a chloride ion in tap water may also be electrostatically repelled. And prevent it from adhering to the surface of the substrate. Therefore, it is possible to prevent a change in the surface characteristics of the substrate caused by the adhesion of such impurities, so that the surface of the substrate can be cleaned. Furthermore, if one of the positive charge amount or the negative charge amount is too large, the tendency to adsorb a negatively charged impurity or a positively charged contaminant by photooxidation is enhanced, and as a result, the surface of the substrate is contaminated, so The surface of the substrate preferably has a state in which the amount of positive charge and the amount of negative charge seem to be balanced. Specifically, it is preferred that the voltage of the surface of the substrate is in the range of -50V to 50V.

Further, a contaminant containing a relatively small amount of a positively or negatively charged insulator (for example, a polyoxygenated oil) may be contaminated if there is only a strong positive or negative charge on the surface of the substrate depending on the kind of the substance. The surface charge of the substance is reversed, and as a result, the contaminant is adsorbed on the surface of the substrate, so that by coexisting both the positively charged substance and the negatively charged substance, such adsorption can be avoided or reduced, thereby preventing penetration. The rate has dropped.

Figure 4 is a conceptual diagram showing a state in which a positive charge and a negative charge are applied to a layer on a surface of a substrate, and is a dielectric or semiconductor-conductor having a negative charge - a dielectric or a semiconductor - having a positive A combination of electric conductors of electric charge is exemplified as a layer. As the negatively-charged conductor and the positively-charged conductor shown in Fig. 4, the above-mentioned ones can be used.

As shown in FIG. 4, a dielectric or semiconductor adjacent to a negatively charged conductor is dielectrically polarized by the influence of the surface charge state of the conductor. As a result, a positive charge is generated in the dielectric or semiconductor on the side adjacent to the negatively charged conductor, and a negative charge is generated in the dielectric or semiconductor on the side adjacent to the positively charged conductor. By these effects, the surface of the combination of dielectric or semiconductor-conductor-dielectric or semiconductor-conductor shown in Fig. 4 becomes positively or negatively charged. The size of the composite of the above conductor and the dielectric or semiconductor (referring to the length of the longest axis passing through the composite) may be in the range of 1 nm to 100 μm, preferably 1 nm to 10 μm, more preferably 1 nm to 1 μm. More preferably, it is in the range of 1 nm to 100 nm.

Fig. 5 is a conceptual diagram showing another aspect in which a positive charge and a negative charge are applied to the above layer.

Fig. 5 shows a state in which a conductor having a negative charge is adjacent to a conductor having a positive charge, and a positive charge and a negative charge are in contact with each other and are less. Further, as the conductor having a negative charge and the conductor having a positive charge, those already described above can be used.

Next, the mechanism for removing contaminants from the surface of the layer having positive and negative charges is shown in Fig. 6.

In this aspect, a substance selected from an anion, a negatively charged conductor or a dielectric, a negatively charged conductor and a dielectric or a semiconductor, a substance having a photocatalytic function, or the like The negatively charged species in the mixture impart positive and negative charges to the layer (Fig. 6(1)).

Contaminants accumulate on the surface of the layer and are photooxidized by the action of electromagnetic waves such as sunlight. Thereby, a positive charge is also applied to the pollutant (Fig. 6 (2)).

An electrostatic repulsion of positive charges is generated between the surface of the layer and the pollutant, and a repulsive force is generated for the pollutant. Thereby, the adhesion of the pollutant to the surface of the layer is lowered (Fig. 6 (3)).

The pollutants can be easily removed from the layer by the physical action of wind and rain (Fig. 6 (4)). Thereby, the substrate can be self-cleaned.

Further, since the surface of the layer also has a negative charge, it also rejects a negatively charged contaminant or a contamination-inducing substance such as a kaolin clay fine powder or a chloride ion, and the adhesion to the surface of the layer is lowered.

The above-mentioned penetrating visible light amount increasing agent may also contain various metals (Ag, Pt). Further, various substances such as metal salts can be contained within a range that does not deactivate the function. Examples of the metal salt include metal salts of aluminum, tin, chromium, nickel, ruthenium, iron, silver, iridium, indium, bismuth, selenium, copper, manganese, calcium, platinum, tungsten, zirconium, zinc, and the like. A part of the metal or non-metal, etc., may also use a hydroxide or an oxide. Specifically, aluminum chloride, tin dichloride and tin tetrachloride, chromium chloride, nickel chloride, antimony trichloride and antimony pentachloride, iron dichloride and ferric chloride, and silver nitrate can be exemplified. , barium chloride, indium trichloride, antimony trichloride, selenium tetrachloride, copper dichloride, manganese chloride, calcium chloride, platinum tetrachloride, tungsten tetrachloride, tungsten dichloride, tungstic acid Various metal salts such as potassium, gold trichloride, zirconium oxychloride, and zinc chloride. Further, examples of the compound other than the metal salt include indium hydroxide, decyl tungstic acid, cerium oxide sol, and calcium hydroxide.

In addition, the positively-charged substances, the negatively-charged substances, or a combination thereof may make the surface of the substrate hydrophilic, thereby preventing or reducing the formation of water droplets on the surface of the substrate. Therefore, it is possible to avoid a decrease in light transmittance due to refraction and diffuse reflection caused by water droplets on the surface of the substrate.

In the present invention, an intermediate layer may be present between the layer containing the organic cerium compound and the inorganic cerium compound and the surface of the substrate. The intermediate layer may include, for example, various organic or inorganic substances that impart hydrophilicity, hydrophobicity, water repellency, or oil repellency to the substrate.

The substrate obtained by the present invention can be used in any field, and in particular, it can be effectively used as a part of a device requiring improvement in light transmittance and reduction in reflectance. For example, it can be used as a surface glass for photovoltaic cells such as solar cells, as a battery for power generation elements, as a surface glass for various displays such as liquid crystal displays, plasma displays, organic EL (electroluminescence) displays, and Brown tube televisions, and optical elements such as lenses. , building materials such as window glass, as well as various light-receiving bodies, illuminants, projectors, polarized glass, optical glass, and the like. In particular, when it is used for the surface glass of a photovoltaic cell such as a solar cell for outdoor use or the surface of a power generation cell, it is possible to contribute to improvement in power generation efficiency by high light transmittance.

Further, when a substrate containing a positively-charged substance, a negatively-charged substance or a mixture of such a visible light amount increasing agent is used for surface treatment, the effect of preventing water droplet formation due to hydrophilization of the surface of the substrate is mutually Therefore, the adhesion of the contaminant is prevented or reduced for a long time by the electrostatic repulsion of the surface of the substrate, so that the high light transmittance of the substrate can be maintained over time. For example, the photocell using the substrate as the surface glass can be continuously performed outdoors. Efficiency of power generation.

[Examples]

Hereinafter, the present invention will be exemplified in more detail by way of examples, but the invention is not limited to the examples.

[Evaluation 1] (evaluation solution 1)

Separate cerium oxide sol liquid WM-12 (Tama Chemical Industry Co., Ltd.), copper and zirconium titanium dioxide aqueous dispersion: Z18-1000 Super A (Sustainable Titania Technology), and doping The silver titanium dioxide aqueous dispersion SP-2 (Sustainable Titania Technology) was adjusted to 0.6% by weight, and then mixed in a weight ratio of 8:1:1, and 2% by weight of the commercially available product was added to the mixture. A white sugar, 20% by weight of an organic hydrazine surfactant: ZB (Sustainable Titania Technology) was used as the evaluation liquid 1.

(evaluation solution 2)

In the pure water, the cerium oxide sol liquid WM-12 (Tama Chemical Industry Co., Ltd.), the tin-doped and copper-titanium dioxide aqueous dispersion: SnZ18-1000 A (Sustainable Titania Technology), by the following The prepared iron-doped titanium dioxide aqueous dispersion was adjusted to 0.6% by weight, and then mixed in a weight ratio of 8:1:1, and 2% by weight of commercially available white sugar was added to the mixed content, 20 The organic hydrazine surfactant: ZB (Sustainable Titania Technology) was used as the evaluation liquid 2.

(Doped iron titanium dioxide aqueous dispersion)

The following solution was prepared: a solution obtained by completely dissolving 0.712 g of FeCl ₃ ‧6H ₂ O in 500 ml of pure water, and further adding 10% of a titanium tetrachloride solution (manufactured by Sumitomo Sitix Co., Ltd.), and then adding Pure water was used to make a 1000 ml solution. Ammonia water obtained by diluting 10% of ammonia water (manufactured by Takasugi Pharmaceutical Co., Ltd.) by 10 times was added dropwise thereto, and the pH was adjusted to 7.0 to precipitate a mixture of iron hydroxide and titanium hydroxide. The precipitate was continuously washed with pure water in a manner that the conductivity in the supernatant was 0.8 mS/m, and the cleaning was completed when the conductivity reached 0.744 mS/m, and 420 g of a hydroxide-containing liquid having a concentration of 0.47% by weight was produced. . Then, while cooling the hydroxide-containing liquid to 1 to 5 ° C, 25 g of 35% hydrogen peroxide (manufactured by Taiki Chemicals Industry Co., Ltd.) was added and stirred for 16 hours to obtain a dark yellow-brown transparent blend. A dispersion of 0.44% by weight of amorphous iron of amorphous titanium peroxide was 440 g. This was concentrated by an ultrafiltration concentrating apparatus to prepare 220 g of the above dispersion having a concentration of 0.85% by weight.

(evaluation solution 3)

The cerium oxide sol liquid WM-12 (Tama Chemical Engineering Co., Ltd.) and the titanium and zirconium-doped titanium dioxide aqueous dispersion: Z18-1000 Super A (Sustainable Titania Technology) were adjusted to pure water respectively. After 0.6% by weight, the materials were mixed at a weight ratio of 9:1, and 2% by weight of commercially available white sugar and 20% by weight of an organic quinone surfactant were added to the mixture: ZB (Sustainable Titania Technology) ) as the evaluation liquid 3.

(evaluation solution 4)

The cerium oxide sol liquid WM-12 (Tama Chemical Industry Co., Ltd.) was adjusted to 0.6% by weight with pure water, and 2% by weight of commercially available white sugar and 20% by weight of organic cerium surfactant: ZB (Sustainable) were added thereto. Titania Technology (share)) was used as the evaluation liquid 4.

(evaluation solution 5)

To the evaluation liquid 4, 10% by weight of an anatase-type titanium dioxide aqueous dispersion: STi-560 B (Sustainable Titania Technology) was added as the evaluation liquid 5.

(Comparative solution 1)

The cerium oxide sol liquid WM-12 (Tama Chemical Industry Co., Ltd.) was adjusted to 0.6% by weight with pure water, and 2% by weight of commercially available white sugar was added thereto as Comparative Liquid 1.

(Evaluation of substrate production)

The evaluation liquids 1 to 5 and the comparative liquid 1 were applied to each of the glass substrates having a size of 50 mm × 50 mm by a commercially available transparent float glass (thickness: 3 mm) by a spray coating method at a ratio of 20 g/m ² . After naturally drying, it was calcined at 580 ° C for 30 minutes (high-temperature heat treatment) to evaluate substrates 1 to 5 and comparative substrate 1. Further, an untreated glass substrate was used as a control.

[Evaluation method]

The transmittance and reflectance of visible light were measured on the evaluation substrates 1 to 5, the comparison substrate 1 and the control, respectively, using an ultraviolet-visible spectrophotometer V-550DS (Japan Spectrophotometer) under the following conditions. Metering mode: %T, %R, response: Medium, scanning speed is 100 nm/min, starting wavelength is 780 nm, end wavelength is 380 nm, and data extraction interval is 1.0 nm. The results are shown in Table 1.

[Table 1]

According to the results of Table 1, it was found that the light transmittance of the evaluation substrates 1 to 5 and the comparative substrate 1 was significantly improved as compared with the control. Further, generally, the sum of the visible light transmittance (A), the visible light reflectance (B), and the visible light absorption rate of the substrate should be 100 (%) or less, but for the evaluation substrates 1 to 5, the light transmittance (A) is observed. The sum of the visible light reflectance (B) and the visible light absorptivity of the substrate exceeds 100 (%), and the amount of light penetrating the substrate in the visible light wavelength region is increased. The magnitude of the amount of transmitted light was: evaluation substrate 2 > evaluation substrate 1 > evaluation substrate 3 > evaluation substrate 5 > evaluation tomb 4 > comparative substrate 1.

[Evaluation 2] (evaluation solution 6~10 and comparison solution 2)

The evaluation liquids 6 to 10 and the comparison liquid 2 were prepared in the same manner as the evaluation liquids 1 to 5 and the comparative liquid 1 except that the commercially available white sugar was added as the pyrolytic organic material.

(Evaluation of substrate production)

The evaluation liquids 6 to 10 and the comparative liquid 2 were applied and heated at 80 ° C for 15 minutes in the same manner as in the production of the evaluation substrate in Evaluation 1, and dried, then washed with pure water, and further dried. (Non-heat treatment) as the evaluation substrates 6 to 10 and the comparison substrate 2. Further, an untreated glass substrate was used as a control.

[Evaluation method]

In the same manner as the evaluation method in Evaluation 1, the transmittances and reflectances of visible light rays were measured for each of the evaluation substrates 6 to 10, the comparison substrate 2, and the control. The results are shown in Table 2.

[Table 2]

From the results of Table 2, it is understood that the same tendency is exhibited when the thermally decomposable organic compound is not used.

Fig. 1 is a schematic view showing an example of a first method for producing a metal-doped titanium peroxide;

Figure 2 is a conceptual diagram showing a positive charge imparting mechanism of a composite;

Figure 3 (1) ~ (4) is a conceptual diagram showing the mechanism for removing contaminants from the surface of a positively charged substrate;

4 is a conceptual diagram showing an example of a positive charge and a negative charge imparting mechanism in the present invention;

Figure 5 is a conceptual diagram showing another example of a positive charge and a negative charge imparting mechanism in the present invention;

6(1) to (4) are conceptual diagrams showing a mechanism for removing contaminants from the surface of a substrate having positive and negative charges.

(no component symbol description)

Claims (15)

A light-transmitting substrate-increasing visible light amount increasing agent comprising an organic germanium compound having an alkyl phthalate structure and/or a polyether structure, cerium oxide, and a metal-doped titanium oxide, and is used for In the case where the surface of the light-transmitting substrate is formed, the amount of light transmitted through the light-transmitting substrate is increased by the visible light emitted from the layer formed on the surface of the light-transmitting substrate. The penetrating visible light amount increasing agent of claim 1, wherein the titanium oxide is titanium peroxide. The penetrating visible light amount increasing agent of claim 1, which further comprises a thermally decomposable organic compound. The penetrating visible light amount increasing agent according to claim 3, wherein the thermally decomposable organic compound is a sugar or a sugar alcohol. The penetrating visible light amount increasing agent according to claim 4, wherein the sugar is at least one selected from the group consisting of monosaccharides and disaccharides. The penetrating visible light amount increasing agent according to claim 3, wherein the thermally decomposable organic compound is a water-soluble organic polymer. The penetration visible light amount increasing agent of claim 1, which further comprises (1) a cation, (2) a positively charged conductor or dielectric, and (3) a positively charged conductor and a dielectric One or two or more kinds of positively charged substances in a group consisting of a composite of semiconductors. The penetration visible light amount increasing agent of claim 1, which further comprises (4) an anion, (5) a negatively charged conductor or dielectric, (6) a negatively charged conductor and a dielectric or One or two or more kinds of negatively-charged substances in a group consisting of a composite of semiconductors. The penetration visible light amount increasing agent of claim 1, which further comprises (1) a cation, (2) a positively charged conductor or dielectric, and (3) a positively charged conductor and a dielectric Or one or more positively charged substances in a group consisting of a composite of semiconductors; and a negatively charged conductor or dielectric selected from (4) anions, (5) having a negative charge, and (6) having a negative charge One or two or more kinds of negatively-charged substances in a group consisting of a conductor and a composite of a dielectric or a semiconductor. A method for producing a highly light-transmitting substrate, characterized in that a penetrating visible light amount increasing agent according to claim 1 is applied to a light-transmitting substrate, and subjected to heat treatment or non-heat treatment. A method of producing a highly light-transmitting substrate according to claim 10, wherein at least a part of said substrate is made of resin, metal or glass. A method for producing a highly light-transmitting substrate according to claim 10, which is subjected to the above heat treatment at a temperature of 400 ° C or higher. A highly light-transmitting substrate obtained by the method for producing a highly light-transmitting substrate according to claim 10. An optical member or optical element having a highly light transmissive substrate as claimed in claim 13. A method for increasing the amount of visible light transmitted through a light-transmitting substrate, characterized in that an organic germanium compound having an alkyl phthalate structure and/or a polyether structure, cerium oxide, and a doping metal are formed on the surface of the light-transmitting substrate. The layer of titanium oxide is irradiated with visible light from the formed layer to increase the amount of visible light transmitted through the light-transmitting substrate.