JP2010101921A - Magnifier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnifier including fine particles of a tungstic oxide or a tungstic oxide compound material on the surface, and having high anti-clouding performance by keeping hydrophilicity for long hours. <P>SOLUTION: In this magnifier including fine particles of the tungstic oxide or the tungstic oxide compound material on the lens surface, a mean particle size of the fine particles is in the range of 1-200 nm, and the aspect ratio of the fine particles is in the range of 1-3.5. When using fine particles of a tungstic oxide or a tungstic oxide compound material having excellent photocatalyst performance under irradiation of visible light, performance of decomposition of organic substance fouling or gas, or antibacterial-disinfection performance can be added. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnifying glass having fine particles of tungsten oxide or a composite material of tungsten oxide on a lens surface.

Surface-hydrophilic members are used in various areas such as anti-fogging, condensation prevention, stain prevention, and water-based paint printing. Recently, surface hydrophilic members using titanium oxide photocatalyst films have been developed and applied to various products. The application of is also disclosed.

When the titanium oxide film is irradiated with ultraviolet rays contained in sunlight, the surface state changes and the surface becomes hydrophilic. At the same time, the film with photocatalytic action oxidizes and decomposes organic substances adhering to the surface and exhibits high hydrophilicity. Antifouling and antifogging effects can be obtained on the surface of glass or the like provided with a titanium photocatalyst.

When a titanium oxide photocatalyst is applied to a hydrophilic member, ultraviolet light is necessary for excitation light, so that excitation light is insufficient indoors and sufficient hydrophilicity cannot be obtained, resulting in insufficient antifogging effect. For this reason, the titanium oxide is mixed with a hydrophilic oxide such as silicon oxide to increase the duration of hydrophilicity, but sufficient performance is not obtained.

In addition, in order to compensate for this lack of excitation light, nitrogen and sulfur are added to titanium oxide, platinum is supported, etc., and visible light response is performed, but the usable wavelength range of light does not widen so much Insufficient performance for indoor use. In addition, the persistence of the hydrophilic effect is equivalent to that of conventional titanium oxide, and the hydrophilicity decreases in a short period in the dark.

On the other hand, tungsten oxide is widely used as a dielectric material for electronic devices, a material for optical elements, an electrochromic material, and a gas sensor material, but is also known as a visible light responsive photocatalytic material. Tungsten oxide has a band gap of 2.5 eV to 2.8 eV. Titanium oxide can only use UV light with a wavelength of 380 nm or less, while visible light near 450 nm can be used. It can be used in the wavelength range of indoor fluorescent lamps and light bulbs. It becomes possible. It is also known that tungsten oxide exhibits hydrophilicity by light irradiation, and films produced mainly by a vacuum deposition method, a sputtering method, a laser ablation method, or a sol-gel method have been reported.

Patent Document 1 describes a photocatalytic material in which a tungsten oxide film is formed on a base material by a sputtering method, and tungsten oxide having a triclinic crystal structure is mainly used.
According to Patent Document 1, a technique is disclosed in which tungsten oxide can be hydrophilized by excitation with visible light, and hydrophilicity is evaluated in the examples. The tungsten oxide film produced by the sputtering method according to this document has a contact angle of 10 ° to 30 ° as an initial value.
In the example, it is described that the contact angle was 5 ° or less after about 20 minutes after the tungsten oxide film was irradiated with ultraviolet rays.

On the other hand, Non-Patent Document 1 discloses a technique in which hydrophilic performance is obtained by performing a heat treatment at 400 ° C. on a tungsten oxide film formed by a thermal evaporation method or a sol-gel method.

In these known techniques, the above-mentioned lack of light becomes a problem when hydrophilized by light, and the heating method becomes a problem for members having a large heat resistance and large area when heated by heating or the like. Furthermore, when the member is made hydrophilic by post-treatment such as light irradiation or heating, the duration tends to be shortened, and regular irradiation or heating is required in a short time.

Further, only by the action of hydrophilization, when an organic substance such as an oil component on the surface adheres, it must be removed by sufficient rain water or water washing, which causes a problem that the use environment is limited. For this reason, the ability to oxidatively decompose organic substances on the surface by photocatalytic action is also necessary, but sufficient photocatalytic performance is not obtained with the above technique.
As a method for producing a tungsten oxide film, the sputtering method, the thermal evaporation method, and the sol / gel method have problems such as limitation of the base material.

On the other hand, it is also possible to form a film using tungsten oxide powder. In order to form a uniform film, it is necessary to use fine tungsten oxide powder. As a method for producing a fine tungsten oxide powder, a method is known in which ammonium paratungstate (APT) is heated in air to obtain a tungsten trioxide powder (Patent Document 2). In Patent Document 2, tungsten trioxide powder having a primary particle diameter of 0.01 μm (BET specific surface area = 82 m ² / g) is obtained by a method of heating APT in air.

Further, Patent Document 3 describes thermal plasma processing as a method for efficiently obtaining fine powder. By applying the thermal plasma treatment, fine powder having a particle diameter of 1 to 200 nm is obtained. However, even if the tungsten oxide fine powder produced by applying these methods is used as it is, the hydrophilicity by light is insufficient and the hydrophilicity cannot be maintained for a long time. No tungsten oxide film has been obtained.
JP 2001-152130 A JP 2002-293544 A JP 2006-102737 A J.Phys.D: Appl.Phys.40 (2007) 1134

  An object of the present invention is to provide a loupe having fine particles of tungsten oxide or a composite material of tungsten oxide, which has excellent hydrophilicity and can maintain its performance for a long time, on the lens surface.

  The loupe according to an aspect of the present invention includes tungsten oxide or tungsten oxide composite fine particles on the lens surface, the average particle diameter of the fine particles is in the range of 1 nm to 200 nm, and the fine particle has an aspect ratio of 1 to 3. .5 range.

In general, metal oxides are hydrophilic, and titanium oxide and tungsten oxide are also considered to have hydrophilic surfaces. However, materials made by a conventionally known process have a low hydrophilicity in a short time in the atmosphere. A material having a hydrophilic property for a long time in a normal state has not been obtained.
According to the present invention, by providing the lens surface with fine particles of tungsten oxide or tungsten oxide composite having an average particle size in the range of 1 nm to 200 nm and an aspect ratio of the fine particles in the range of 1 to 3.5. A loupe with a lens surface that exhibits hydrophilicity, greatly extends the hydrophilic retention time in the dark, is easy to remove stains, defogging, and dirt, and has improved mechanical strength and life. It is to provide.

  When fine particles of tungsten oxide or a composite material of tungsten oxide that excels in photocatalytic performance under visible light irradiation are used, even when hydrophilicity decreases due to organic contamination, the organic matter is decomposed by exposure to light, and hydrophilicity is reduced. Can be achieved in a short time, and high antifogging performance can be obtained. In addition, it is possible to provide a loupe having excellent organic gas decomposition performance and photocatalytic performance such as antibacterial and sterilization performance under visible light irradiation.

Hereinafter, modes for carrying out the present invention will be described.
The loupe according to an embodiment of the present invention has fine particles of tungsten oxide or a composite material of tungsten oxide on the lens surface, the average particle size of the fine particles is in the range of 1 nm to 200 nm, and the aspect ratio of the fine particles is 1-3. It is the range of 5.

  The loupe according to an embodiment of the present invention is characterized in that the lens surface includes fine particles of tungsten oxide or a composite material of tungsten oxide. The material of the lens used in the loupe in the present invention is not limited, but the main material is glass or plastic material. In the case of a plastic material, for example, polycarbonate, MMA / styrene copolymer resin, cycloolefin resin, polymethyl methacrylate resin and the like are used.

On the lens surface, the tungsten oxide fine particles may be present alone, in the form of other elements alone or mixed with compounds of other elements, or in the form of compounds such as complex oxides formed with other elements. You may do it. Other elements may be supported on tungsten oxide in the form of a simple substance or a compound. Furthermore, fine particles in which a single element of tungsten oxide and a tungsten oxide composite material are mixed may be used.

  In the loupe according to the embodiment of the present invention, it is preferable that the fine particles of tungsten oxide or the tungsten oxide composite material are included in the range of 0.1% by mass to 95% by mass in the layer including the fine particles. If it is less than 0.1% by mass, the hydrophilicity of the fine particles of tungsten oxide or tungsten oxide composite material cannot be sufficiently exhibited, which is not preferable. The case of 5 mass% or more is more preferable. On the other hand, if it exceeds 95% by mass, the surface strength is insufficient, which is not preferable.

In the lens surface of the loupe according to an embodiment of the present invention, the average particle size of the fine particles of tungsten oxide or a composite material of tungsten oxide is in the range of 1 nm to 200 nm. The BET specific surface area of the tungsten oxide powder or the tungsten oxide composite powder is preferably in the range of 4.1 to 820 m ² / g.

  Here, the particle diameter is obtained by directly evaluating the fine particles used for forming the lens surface or the fine particles provided on the surface by SEM, TEM or the like and analyzing the image of the photograph. The average particle diameter refers to a biaxial average diameter obtained by (major axis + minor axis) / 2 as a particle diameter, and these average particle diameters (D50) are used, and n = 50 or more volume-based integrated diameters of particles. It calculates | requires based on the average particle diameter (D50). The average particle diameter (D50) may coincide with the average particle diameter converted from the specific surface area.

The surface having excellent hydrophilicity is preferably in a uniform state, and preferably has a smaller primary particle diameter or a larger specific surface area. Accordingly, sufficient characteristics cannot be obtained when the average primary particle diameter of the tungsten oxide or tungsten oxide composite fine particles exceeds 200 nm or when the BET specific surface area is less than 4.1 m ² / g. On the other hand, when the average particle size of the primary particles of tungsten oxide or tungsten oxide composite particles is less than 1 nm or the BET specific surface area exceeds 820 m ² / g, the particles become too small and are handled as powder. Inferiority reduces practicality. Moreover, since dispersibility falls, it becomes difficult to disperse | distribute uniformly on the surface and sufficient hydrophilicity cannot be exhibited.

The performance of the photocatalyst powder is generally higher when the specific surface area is larger and the particle size is smaller. Therefore, when the fine particles of tungsten oxide or tungsten oxide composite material according to the present invention have photocatalytic performance, when the average particle diameter of primary particles exceeds 200 nm, or when the BET specific surface area is less than 4.1 m ² / g, Since the photocatalytic performance of the fine particles is lowered and it is difficult to form a uniform and stable surface, sufficient photocatalytic performance cannot be obtained. In addition, when the average particle size of the primary particles of tungsten oxide or tungsten oxide composite particles is too small, the dispersibility of the particles decreases, making it difficult to uniformly disperse on the surface, and sufficient photocatalytic performance is obtained. Hateful.

The average particle size of primary particles of tungsten oxide or tungsten oxide composite fine particles is preferably in the range of 2.7 nm to 75 nm, more preferably in the range of 5.5 nm to 51 nm. Preferably the BET specific surface area in the range of ^{11m 2} / ^g~300m 2 / g, more preferably in the range of ^{16m 2} / ^g~150m 2 / g.

  The loupe according to the embodiment of the present invention is characterized in that the individual aspect ratio of the fine particles of tungsten oxide or tungsten oxide composite material provided on the lens surface is in the range of 1 to 3.5. The aspect ratio is a numerical value obtained by (major axis / minor axis) of fine particles, and is 1 when the shape of the fine particles is a sphere. When the aspect ratio exceeds 3.5, since the fine particles have an elongated shape, the dispersion of the fine particles in the surface layer becomes non-uniform, and the hydrophilicity is lowered. The aspect ratio is preferably in the range of 1-2.

In the loupe according to the embodiment of the present invention, it is preferable that the thickness of the layer having the fine particles of tungsten oxide or tungsten oxide composite on the lens surface is in the range of 2 nm to 50 μm.
The method of forming a layer comprising fine particles of tungsten oxide or tungsten oxide composite on the surface of the lens substrate is a physical formation method such as reverse gravure deposition or sputtering, a sol-gel solvent or the fine particles dispersed. General coating methods such as spin coating using a liquid, dip, spray, etc., producing a transfer film or sheet comprising fine particles, coating the substrate surface by the transfer method, and attaching a film comprising fine particles Known methods such as kneading into a method and a base material, and forming a surface layer simultaneously in the step of forming the base material can be applied. It is also necessary to select a suitable method depending on the type and shape of the substrate.

  If the thickness of the layer provided with the fine particles is less than 2 nm, it is difficult to form a uniform layer. On the other hand, if the thickness exceeds 50 μm, cracks are generated in the layer, or the adhesion to the substrate is reduced and the film is easily peeled off. The thickness of the layer provided with the fine particles is preferably in the range of 4 nm to 5 μm. More preferably, it is the range of 10 nm-1 micrometer.

  In the loupe according to the embodiment of the present invention, the layer having the fine particles is preferably formed on the surface of the lens substrate via an inorganic base layer. A loupe used in a place with a lot of light irradiation may cause peeling of the base material or choking due to oxidative decomposition by fine particles of tungsten oxide or a tungsten oxide composite material. Therefore, durability can be improved by forming an underlayer between the layer having fine particles and the substrate. In addition, the adhesion between the base material and the layer containing the fine particles can be improved by the base layer. The underlayer preferably has a high affinity for both the base material and the layer having fine particles, and the thickness is preferably 10 to 200 nm.

For the underlayer, silicon-modified resins such as acrylic-modified silicon resin compounds and silicon-modified acrylic resin compounds, colloidal silica-containing resins such as resins obtained by reacting silica colloid particles in organosol with silane and acrylic, silicone silanes, A polysiloxane-containing resin mixed with a condensate of alkoxysilanes (alkyl silicate) or the like is used.
The underlayer is generally formed by applying a solution containing the resin compound. The solution may be one in which a resin is dispersed in a solvent such as toluene, xylene, ketone, alcohol, or an aqueous emulsion type. The method for forming the base layer on the base material is not particularly limited, and various coating methods such as brush coating, spray coating, spin coating, dip coating, roll coating, gravure coating, and bar coating can be applied.
A silicon oxide layer or an aluminum oxide layer formed by vapor deposition or the like can also be used.

In the loupe according to the embodiment of the present invention, the light transmittance of the layer having the fine particles at a wavelength of 550 nm is preferably 50% or more. A light transmittance of 50% or more at a wavelength of 550 nm means that the transparency is high, and the transparency of the lens is sufficiently maintained. When the light transmittance is less than 50%, the light transmittance is insufficient, so that the transparency is lowered and the light transmittance of the lens is lowered.

  The loupe according to the embodiment of the present invention preferably exhibits hydrophilicity regardless of light. Light includes fluorescent lamps, sunlight, white LEDs, light bulbs, halogen lamps, xenon lamps and other general illumination, visible light irradiated with blue LEDs, blue lasers, etc. as light sources, and light having a wavelength in the ultraviolet region. In general, the lens surface of the loupe according to the embodiment of the present invention exhibits hydrophilicity regardless of the type of light and whether or not light is irradiated. By having such a surface, the hydrophilic retention time in the dark place of the lens surface of the loupe can be greatly extended. Moreover, the better the crystallinity of the particles, the higher the hydrophilicity can be shown even in the dark or under low light illumination.

In the loupe of the embodiment of the present invention, it is preferable that the crystal orientation of the lens surface is not oriented. The orientation state of the crystal orientation on the lens surface can be confirmed by performing X-ray diffraction or backscattered electron diffraction. For example, among the existing peaks in the 2θ range of 22 to 25 ° by X-ray diffraction, the diffraction peak with the highest intensity is A, the diffraction peak with the second highest intensity is B, and the diffraction with the third highest intensity When the peak is C, the film is not oriented when any of the following patterns (1) to (3) is satisfied. Here, the peak intensity is measured by taking a peak at a high peak and reading the intensity value at that height. If there is a shoulder, the intensity value is read and used as a peak.

(1) When there are three peaks The peak intensity ratio B / A is 0.3 or more and the peak intensity ratio C / A is 0.3 or more. (2) When there are two peaks Between A and B When the lowest intensity of the valley is read as D, the peak intensity ratio B / A is 0.3 or more and B / 2 <D
(3) When there is only one peak, the full width at half maximum is 1 ° or more

  In addition, when the lens surface of the loupe according to the embodiment of the present invention has an amorphous crystal structure, the crystallinity of the tungsten oxide or the tungsten oxide composite material is low, and it is not preferable because desired characteristics cannot be obtained.

Since a typical crystal structure of tungsten oxide is a ReO ₃ structure, a crystal surface having a high reaction activity having oxygen in the outermost surface layer is easily exposed. For this reason, high hydrophilicity is exhibited by adsorbing water. When fine particles of tungsten oxide or tungsten oxide composite material prepared by vapor deposition, sputtering, or sol-gel method are formed, the crystals of the fine particles become amorphous and difficult to hydrophilize. Become the surface. However, when the heat treatment temperature is raised, the crystals are oriented and at the same time the hydrophilicity is lowered. The reason for this is considered to be that there are many crystal planes on the surface that are difficult to show hydrophilicity.

  In contrast, when the lens surface is formed using the fine particles of the tungsten oxide or the tungsten oxide composite material according to the present embodiment, the surface having good crystallinity and hydrophilicity is uniformly oriented in an arbitrary direction. The state existing in can be formed. For this reason, it is possible to exhibit higher hydrophilicity than other manufacturing methods, and to express hydrophilicity irrespective of light.

  The lens surface layer of the loupe according to the embodiment of the present invention can be formed by the above-described manufacturing method. However, in the manufacturing method in which the high-temperature heat treatment is performed after the surface layer is formed, the crystal orientation is easily oriented, and the hydrophilic layer is hydrophilic. Can not improve. For this reason, it is necessary to adjust manufacturing conditions, such as heat processing time and processing temperature, appropriately.

When the lens surface of the loupe according to the embodiment of the present invention is formed of tungsten oxide fine particles alone, the tungsten oxide fine particles may contain a metal element or the like as a trace amount of impurities. The content of the metal element as the impurity element is preferably 2% by mass or less. Examples of the impurity metal element include elements generally contained in tungsten ore and contaminating elements mixed when producing a tungsten compound used as a raw material. For example, Fe, Mo, Mn, Cu, Ti, Al, Ca, Ni, Cr, Mg, etc. are mentioned. Since these elements sometimes work effectively on the photocatalytic performance, the content is controlled as necessary.

The loupe according to an embodiment of the present invention preferably includes a transition metal element in the range of 0.01% by mass to 50% by mass in the surface layer of the lens including the fine particles. The transition metal element is an element having an atomic number of 21 to 29, 39 to 47, 57 to 79, or 89 to 109. By providing the transition metal element in the range of 0.01% by mass to 50% by mass, the performance can be further improved.

  The transition metal element may exist in any form such as a simple substance, an oxide, a complex oxide, or a compound, and forms a complex oxide or compound with tungsten oxide or is supported on tungsten oxide. Also good. When the content of the transition metal element exceeds 50% by mass, the characteristics of tungsten oxide may be deteriorated. The content of the transition metal element is preferably 0.05% by mass to 10% by mass, and more preferably 0.1% by mass to 5% by mass.

The loupe according to the embodiment of the present invention may include TiO ₂ in the range of 0.01% by mass to 50% by mass in the surface layer of the lens including the fine particles. By including TiO ₂ , the performance can be further improved in an environment where light including ultraviolet rays such as sunlight is irradiated. When TiO ₂ is less than 0.01% by mass, the effect of TiO ₂ cannot be exhibited. On the other hand, when the amount exceeds 50% by mass, the amount of fine particles of tungsten oxide or a tungsten oxide composite material is relatively reduced, and thus hydrophilicity in a dark place cannot be improved.

In the loupe according to the embodiment of the present invention, the surface layer of the lens including the fine particles may be formed on the layer including TiO ₂ . By adopting such a structure, it is possible to easily form a film without adjusting a paint containing tungsten oxide or a tungsten oxide composite and TiO _2, and to improve hydrophilicity in a dark place. It becomes possible.

  In addition, the loupe according to the embodiment of the present invention includes at least one element selected from Cu, Zn, and Ag in a range where the surface layer of the lens including the fine particles is in the range of 0.001% by mass to 1% by mass. May be. By adding these elements, it is possible to provide a multifunctional loupe imparted with antibacterial performance.

The above-described transition metal elements, Cu, Zn, and Ag are contained in metals, oxides, composite oxides, compounds, and the like, and may be mixed on the surface of the member, tungsten oxide fine particles, or tungsten oxide The fine particles of the composite material may be supported. Further, a compound may be formed with tungsten oxide or a tungsten oxide composite material. When the content of Cu, Zn, and Ag is less than 0.001% by mass, the performances of these cannot be sufficiently exhibited. Moreover, even if it contains exceeding 1 mass%, since it is difficult to improve the performance effectively and it will raise cost, it is not preferable. The range of 0.01% by mass to 0.1% by mass is effective because it is effective and can reduce the cost.

In the loupe according to the embodiment of the present invention, the surface of the lens including the fine particles may include an inorganic binder and / or an organic binder. When the lens surface of the loupe according to the embodiment of the present invention includes an inorganic binder and / or an organic binder, it is possible to adjust the strength, hardness, adhesion to the base material, and the like to desired characteristics. It becomes.

Examples of the inorganic binder include products obtained by decomposing hydrolyzable silicon compounds such as alkyl silicates, silicon halides and their partial or hydrolyzed products, organic polysiloxane compounds and their polycondensates, silica, Colloidal silica, water glass, silicon compound, phosphate such as zinc phosphate, metal oxide such as zinc oxide and zirconium oxide, heavy phosphate,
Cement, plaster, lime, enamel frit, etc. are used. Moreover, as an organic binder, a fluorine-type polymer, a silicon-type polymer, an acrylic resin, an epoxy resin, a polyester resin, a melamine resin, a urethane resin, an alkyd resin etc. are used, for example. The type of the binder is appropriately selected according to the material of the base material to be used and intended characteristics.

Further, the surface layer having the fine particles may have at least one selected from SiO ₂ , Al ₂ O ₃ , and ZrO ₂ on the surface, and is contained in the range of 5% by mass to 99.9% by mass. It is preferable to do. These components show hydrophilicity, and especially SiO ₂ shows high hydrophilicity. However, when the fine particles of tungsten oxide or a composite material of tungsten oxide have photocatalytic performance, the surface of the member can be cleaned by the effect of this organic matter decomposition, so in order to maintain hydrophilicity for a long time, these components are It is preferable that it is the range of 10 mass%-50 mass%.

On the other hand, especially SiO ₂ may be provided in a range of 10% by mass to 80% by mass in view of transparency. In the loupe of the present invention, since the transparency of the surface layer of the lens is particularly required, it is desirable that the refractive index of the surface layer is close to that of the substrate. Tungsten oxide has a relatively high refractive index. By mixing SiO ₂ having a low refractive index, the refractive index of the surface layer is lowered, and a more transparent loupe is obtained. If it is 10% by mass or less, the effect of reducing the refractive index is small, and if it is 80% by mass or more, it is difficult to ensure the strength of the surface layer. Furthermore, since the SiO ₂ powder itself is hydrophilic, it leads to an improvement in hydrophilic retention time.

  The loupe according to the embodiment of the present invention may have a photocatalytic performance under visible light irradiation. In general, visible light is light in the region of 380 nm to 830 nm, and is irradiated with general illumination such as white fluorescent lamp, sunlight, white LED, light bulb, halogen lamp, xenon lamp, blue LED, blue laser, etc. as a light source. Light. Photocatalytic performance is generated by absorbing light and exciting a pair of children and holes for one photon, activating the excited hydroxyl group and acid on the surface by oxidation-reduction, and activation The active oxygen species has the effect of oxidatively decomposing organic matter and the like, and exhibiting hydrophilicity, antibacterial / sterilizing performance, and the like. The loupe according to the embodiment of the present invention exhibits photocatalytic performance in a normal indoor environment.

  The evaluation of the photocatalytic performance of the member according to the present embodiment, that is, the decomposition performance of organic matter, is performed by, for example, applying oleic acid to the film, irradiating with visible light, and measuring the temporal change in the contact angle of water. When it has photocatalytic performance, even if it is a large contact angle immediately after coating, the contact angle is lowered by decomposing oleic acid, and eventually shows hydrophilicity.

In order that the surface of the lens of the loupe according to the embodiment of the present invention has photocatalytic performance, it can be obtained by using fine particles of tungsten oxide or a tungsten oxide composite material having photocatalytic performance. Tungsten trioxide having a crystal structure in which at least one selected from monocrystal and triclinic crystal (monoclinic crystal, triclinic crystal, or mixed crystal of monoclinic crystal and triclinic crystal) or orthorhombic crystal mixed therewith When the powder is used, high photocatalytic performance can be obtained. Furthermore, when the crystal structure of the tungsten trioxide powder is a mixed crystal of monoclinic crystal and triclinic crystal, or a mixed crystal of monoclinic crystal, triclinic crystal and orthorhombic crystal, higher photocatalytic performance can be obtained.
When the above-mentioned tungsten oxide or a composite material of tungsten oxide has photocatalytic performance, the crystal structure is important. Therefore, when producing a coating liquid for forming the surface layer, the fine particles are dispersed in the fine particle dispersion treatment step. It is necessary to set conditions that do not give too much distortion.

  In addition, the photocatalytic performance can be obtained by providing the transition metal element in the form of a simple substance, an oxide, a complex oxide, or a compound. The simple substance or compound of the transition metal element may be mixed with or supported on the fine particles of the tungsten oxide or the tungsten oxide composite material, or may form a compound such as a composite oxide. .

  Here, the loupe according to the embodiment of the present invention preferably has an arithmetic average surface roughness Ra of 1 nm to 1000 nm with a lens surface having a reference length of 100 μm. Ra is an arithmetic mean roughness Ra value defined in JIS B 0601 (2001), and can be calculated from a cross-sectional curve observed and measured using a surface shape measuring device, a scanning probe microscope or an electron microscope. .

  In order to obtain high hydrophilic performance, the surface is preferably smooth. However, in order to increase the retention time of the hydrophilic performance, the surface needs to be slightly uneven, and the surface roughness Ra is 1 nm or more. Is preferred. On the other hand, when the arithmetic average surface roughness Ra when the reference length is 100 μm is more than 1000 nm, the surface of the film is rough, so that the meaning of antifogging and contamination prevention, which are inherent hydrophilic effects, is lost. When Ra exceeds 1000 nm, the surface becomes cloudy, and it is easy to get dirty due to the unevenness, making it difficult to remove dirt with water.

  Further, the presence of non-uniformity such as the presence of coarse particles of tungsten oxide or tungsten oxide composite is also a factor that increases Ra, and in this case, the activity of the tungsten oxide or tungsten oxide composite is impaired. Therefore, the hydrophilic performance is lowered. Furthermore, when Ra is remarkably large, it is difficult to measure the contact angle, which is a hydrophilicity evaluation method. The arithmetic average surface roughness Ra when the reference length of the surface of the member according to the embodiment of the present invention is 100 μm is preferably 2 nm to 100 nm.

In addition, the lens surface of the loupe according to the embodiment of the present invention preferably has an average length RSm of the contour curve element when the length is 100 μm is at least twice Ra. When RSm is within this range with respect to Ra described above, the surface is smooth and high hydrophilicity can be exhibited. If it is less than 2 times Ra, the unevenness is large and not preferable.
The average length RSm of the contour curve element on the surface of the member according to the embodiment of the present invention is more preferably in the range of three times or more.

  In the loupe according to the embodiment of the present invention, the surface having the fine particles may be formed of a film. The term “film” refers to all thin-film members. The material forming the film is not limited, but the main material is a synthetic resin material, for example, polyethylene terephthalate, vinyl chloride, acrylic, polycarbonate, polyolefin, polyethylene, polypropylene, polystyrene, ethylenetetrafluoroethylene resin, etc. are used. . Moreover, the inorganic material formed with silicic acid etc. may be sufficient. The thickness of the film is preferably 10 μm to 250 μm.

In the loupe of the embodiment of the present invention, when the layer having the fine particles of tungsten oxide or tungsten oxide composite material on the lens surface is formed of a film, the thickness of the layer is preferably in the range of 2 nm to 50 μm.
The method of forming a layer comprising fine particles of tungsten oxide or tungsten oxide composite on the surface of the film is a physical formation method such as reverse gravure deposition or sputtering, a sol-gel solvent or a liquid in which the fine particles are dispersed. General coating methods such as spin coating, dip, spraying, etc., producing transfer films or sheets with fine particles and coating the substrate surface by the transfer method, kneading into the substrate, A known method such as forming a surface layer at the same time in the forming step can be applied. It is also necessary to select a suitable method depending on the type and shape of the substrate.

When the surface of the lens of the loupe according to the embodiment of the present invention is formed of a film, it is preferable to provide a pressure-sensitive adhesive layer on the surface opposite to the surface having the layer including the fine particles. By providing the pressure-sensitive adhesive layer, a film can be easily attached to the surface of the substrate, and hydrophilicity can be imparted without being restricted in the properties and shape of the substrate.
The material of the pressure-sensitive adhesive layer can be appropriately selected, but preferably contains an acrylic resin, an acrylic-modified silicone resin compound or a silicone-modified acrylic resin compound as a main component, a silicone-modified resin, colloidal silica, alcohols such as ethanol and propanol, A material containing water can be applied. Although the thickness of an adhesive layer is not specifically limited, 0.2 micrometer or more is preferable. The method for forming the pressure-sensitive adhesive layer is not particularly limited, and various coating methods such as brush coating, spray coating, spin coating, dip coating, roll coating, gravure coating, and bar coating can be applied.

  The fine particles of the tungsten oxide or the tungsten oxide composite material included in the loupe according to the embodiment of the present invention described above are produced, for example, as follows. The fine particles of the tungsten oxide or the tungsten oxide composite material are manufactured by applying a sublimation process. It is also effective to combine a heat treatment process with a sublimation process. According to the fine particles of tungsten oxide or tungsten oxide composite material produced by applying a sublimation process or a combination of a sublimation process and a heat treatment process, the above-described average particle diameter (D50) and crystal structure can be stably realized. . Furthermore, the value converted from an average particle diameter (D50) and a BET specific surface area approximates, and it can be set as the powder with a small particle size dispersion | variation.

As the raw material for the sublimation process, metallic tungsten or tungsten compound particles or molded products, or a tungsten compound solution can be used.
Examples of the method for sublimating the tungsten raw material in the oxygen atmosphere in the sublimation process include at least one treatment selected from inductively coupled plasma treatment, arc discharge treatment, laser treatment, electron beam treatment, and gas burner treatment. Among these, in laser processing or electron beam processing, a sublimation process is performed by irradiating a laser or electron beam. Lasers and electron beams have a small irradiation spot diameter, so it takes time to process a large amount of raw materials at once, but there is an advantage that it is not necessary to strictly control the stability of the raw material particle size and supply amount. .

  Inductively coupled plasma treatment and arc discharge treatment require adjustment of the plasma and arc discharge generation region, but a large amount of raw material powder can be oxidized at a time in an oxygen atmosphere. In addition, the amount of raw material that can be processed at one time can be controlled. Although the gas burner treatment is relatively inexpensive, it is difficult to treat a large amount of raw material powder or raw material solution. For this reason, the gas burner treatment is inferior in terms of productivity. The gas burner treatment is not particularly limited as long as it has sufficient energy for sublimation. A propane gas burner or an acetylene gas burner is used.

  On the other hand, the tungsten oxide composite material according to the embodiment of the present invention is mixed with or supported by the tungsten oxide fine particles produced by the manufacturing method as described above and another element alone or a compound of another element. It exists in a form in which a compound such as a composite oxide with other elements is formed. In the manufacturing method described above, by treating tungsten oxide simultaneously with another element, fine particles of a composite material in which a compound such as a composite oxide of tungsten oxide and another element is formed can be formed.

  When the surface layer including the fine particles is formed by coating, a liquid in which the fine particles and a solvent are mixed and subjected to a dispersion treatment such as an ultrasonic disperser, a wet jet mill, or a bead mill is used. When the fine particles of tungsten oxide or a composite material of tungsten oxide have photocatalytic performance, it is necessary to set a dispersion treatment condition that does not excessively strain the fine particles in the dispersion treatment.

In addition, the fine particles of the tungsten oxide or tungsten oxide composite material of this embodiment are excellent in dispersibility because the zeta potential in an aqueous solution having a pH of 1 to 7 is negative, and thus can be applied thinly and uniformly on the substrate. A uniform surface layer can be formed.

  The loupe according to the embodiment of the present invention has high hydrophilicity in its lens and can maintain its performance for a long time. In addition, such a lens surface exhibits a high anti-fogging effect, maintains the transparency of the lens, and has an added value that does not cloud even in environments where there is steam or where the conventional lens is clouded due to temperature differences. It becomes possible to provide a high loupe. In addition, when tungsten oxide powder with excellent photocatalytic performance or fine particles of a tungsten oxide composite material is used, it is possible to provide a loupe having excellent photocatalytic performance such as organic matter decomposition performance, hydrophilicity, antibacterial performance, and disinfection performance. It becomes possible.

  Next, specific examples of the present invention and evaluation results thereof will be described. In addition, this invention is not limited to the following Example.

Example 1
First, a tungsten oxide powder having an average particle size of 0.5 μm was prepared as a raw material powder. This raw material powder was sprayed onto RF plasma together with a carrier gas (Ar), and argon was flowed as a reaction gas at a flow rate of 40 L / min and oxygen at a flow rate of 40 L / min. In this manner, a tungsten oxide powder was produced through a sublimation process in which the raw material powder was subjected to an oxidation reaction while being sublimated. Further, the tungsten oxide powder was heat-treated in the atmosphere at 400 ° C. × 2 h.

  Using n-butanol, the resulting tungsten oxide fine particles were added with 20% by weight of ethyl silicate (SSC-1 made by Colcoat) as a binder and dispersed to create a photocatalyst paint (concentration 5%). did. This paint was applied to A4 size glass with a bar coater to a thickness of about 10 μm, and dried at 120 ° C. for 30 minutes to produce a glass coated with fine particles.

The obtained layer having tungsten oxide fine particles on the glass was evaluated, and the major and minor diameters of the fine particles and the average particle size (D50) of the primary particles were measured. The average particle diameter was measured by image analysis of a TEM photograph. H-7100FA manufactured by Hitachi, Ltd. was used for TEM observation, and an enlarged photograph was subjected to image analysis to extract 50 or more particles, and a volume-based integrated diameter was obtained to calculate D50. Further, the BET specific surface area of the fine particles before the preparation of the paint was measured using a specific surface area measuring device Macsorb 1201 manufactured by Mountec. Pretreatment was performed in nitrogen at 200 ° C. for 20 minutes. Table 1 shows the results of the average particle diameter converted from the average particle diameter, the aspect ratio, the thickness of the layer provided with the tungsten oxide fine particles, and the specific surface area.
Next, arithmetic average surface roughness Ra and RSm were measured for the obtained film using a surface shape measuring device Dektak 6M manufactured by Arubac, with a reference length of 100 μm. Moreover, X-ray diffraction confirmed the orientation of crystal orientation using the JEOL X-ray-diffraction apparatus JDX-3500. As a result of the measurement, it was confirmed that the surface roughness Ra was 35 nm, the RSm was as smooth as 190 nm, and the crystal orientation was not oriented.
Furthermore, the transmittance when irradiated with light having a wavelength of 550 nm was measured using a UV-Vis spectrophotometer UV-2550 manufactured by Shimadzu Corporation. As a result, the transmittance was 70%.

Next, the hydrophilicity of the produced surface layer was evaluated.
Using the contact angle meter (“CA-D” manufactured by Kyowa Interface Science Co., Ltd.), the contact angle with respect to 0.4 mg of water droplets was measured for the surface layer described above, and the hydrophilicity was evaluated. It was. The time lapse was measured immediately after the surface layer was created, after being stored for 3 days in a dark environment in a normal laboratory environment, and then for 1 month in a dark place. In addition, the film after being stored in a dark place for 1 month was irradiated with visible light for 1 h, and the contact angle thereafter was also measured. A white fluorescent lamp (FL20SS · W / 18 manufactured by Toshiba Lighting & Technology) was used as a light source, and light having a wavelength of less than 380 nm was cut using an ultraviolet cut filter (manufactured by Nitto Jushi Kogyo Co., Ltd., Clarex N-169). The illuminance was adjusted to 1500 lx. The evaluation results are shown in Table 1.

  The definition of hydrophilicity is not clear, but is often said to be hydrophilic when the contact angle is 30 ° or less. In particular, when the contact angle is 10 ° or less, it is said to exhibit high hydrophilicity. This sample was confirmed to remain hydrophilic for a long time in the dark.

Furthermore, in order to confirm the hydrophilic effect by the organic substance decomposition | disassembly of a photocatalyst, when oleic acid was apply | coated by the method shown by JISR1703-1 (2007) and the visible light of 1500 lx was irradiated on the obtained surface layer The transition of the water contact angle was evaluated. In addition, about the light source, the same thing as the above was used. The evaluation results after 24 h, 48 h, and 72 h are shown in Table 1. For comparison, the contact angle after irradiation with ultraviolet light 0.5 mW / cm ² for 72 hours was evaluated using a black light (FL20S · BLB · JET20W, manufactured by Toshiba Lighting & Technology Corp.). Although sufficient hydrophilicity was not shown by irradiation with visible light, the contact angle of water decreased with time and oleic acid was decomposed, but the effect was small.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Examples 2-3)
A pellet of tungsten oxide powder having a density of 4.5 g / cm ³ was prepared as a raw material. This was placed in a reaction vessel and irradiated with a CO ₂ laser while maintaining the pressure at 3.5 kPa while flowing at a flow rate of oxygen of 10 L / min. Tungsten oxide powder produced by laser treatment was heat-treated in air at 700 ° C. for 0.5 h to obtain fine particles of Example 2. Further, a tungsten oxide powder was produced through the same sublimation process as in Example 1. The obtained tungsten oxide powder was heat-treated in air at 900 ° C. for 1.5 hours to obtain fine particles of Example 3. About these microparticles | fine-particles, the layer which comprises the said microparticles | fine-particles on glass was produced like Example 1, and the average particle diameter, the aspect-ratio, and the thickness of the layer were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 1, and evaluated hydrophilicity. The evaluation results are shown in Table 1. Neither Example 2 nor Example 3 was oriented, and the light transmittance was 70%.
As a result, the contact angle was 10 ° or less in the dark, and it was confirmed that the hydrophilicity was maintained for a long time in the dark. Although oleic acid was decomposed, the effect was small.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Comparative Example 1)
A tungsten oxide powder was produced through the same sublimation process as in Example 1. The obtained tungsten oxide powder was heat-treated in air at 1000 ° C. for 0.5 h to obtain the fine particles of Comparative Example 1. About these microparticles | fine-particles, the layer which comprises a microparticle on glass was produced like Example 1, and the average particle diameter, the aspect-ratio, and the thickness of the layer were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 1, and evaluated hydrophilicity. The evaluation results are shown in Table 1. Although there was no orientation, the light transmittance was 30%.
As a result, it was confirmed that the contact angle was 10 ° or more in the dark and the contact angle increased in the dark. The decomposition of oleic acid was very slow.
Furthermore, when this sample was applied to the surface of the loupe lens in the same manner as in the above example and exposed to steam, water droplets from the steam adhered to the surface of the lens, resulting in cloudiness, and the image clearly confirmed. I couldn't.

Example 4
For the fine particles obtained in Example 2, a layer comprising fine particles having a thickness of 55 μm was produced on glass in the same manner as in Example 1. As a result, the same hydrophilicity as in Example 2 was exhibited, but cracks were partially generated on the surface, resulting in problems in glass productivity and handleability. Moreover, the transmittance | permeability was as low as 40% and the transparency of the base material was reduced.

(Example 5)
A photocatalyst coating material was produced in the same manner as in Example 1 for the fine particles obtained in Example 2. After applying polysiloxane paint (JSR Glassca) to A4 size glass as an underlayer, apply the paint to a thickness of 0.3 μm with a bar coater and dry at 120 ° C. for 30 min to produce the applied glass. did.
As a result, the hydrophilicity was the same as in Example 2.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 6)
A tungsten oxide powder was produced through the same sublimation process as in Example 1. The obtained tungsten oxide powder was heat-treated in air at 500 ° C. for 2 hours to obtain fine particles of Example 6. For these fine particles, a layer having a thickness of 0.3 μm was formed on glass in the same manner as in Example 1, and the average particle size, aspect ratio, and layer thickness were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 1, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more.
As a result, the contact angle was 10 ° or less in the dark, and it was confirmed that high hydrophilicity was maintained for a long time in the dark. Moreover, it was decomposed by oleic acid and showed high hydrophilicity after 72 h light irradiation. The reason why the hydrophilicity was higher in the dark than in Examples 1 to 3 and a higher photocatalytic effect was obtained is that crystallinity was improved by optimizing the production conditions.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 7)
The same sublimation process and heat treatment process as in Example 3 were carried out except that tungsten oxide powder having a high content of Fe, Mo, or the like was used as a raw material to be put into plasma, and a tungsten oxide composite powder containing 300 ppm of Fe was used. Produced. About the obtained tungsten oxide composite powder, a layer having a thickness of 0.3 μm was produced on glass in the same manner as in Example 6, and the average particle diameter, aspect ratio, and layer thickness were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 8)
The tungsten oxide fine particles obtained in Example 6 were mixed with 10% by mass of TiO ₂ powder. For the tungsten oxide composite material powder thus obtained, a layer having a thickness of 0.3 μm was formed on the glass in the same manner as in Example 6, and the average particle diameter, aspect ratio, and layer thickness were confirmed. It was. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

Example 9
After a TiO ₂ layer was formed on the glass, a layer having a thickness of 0.3 μm was formed from the paint obtained in Example 6, and the average particle size, aspect ratio, and layer thickness were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 10)
1% by mass of copper oxide (CuO) powder was mixed with the tungsten oxide fine particles obtained in Example 6. For the tungsten oxide composite material powder thus obtained, a layer having a thickness of 0.3 μm was formed on the glass in the same manner as in Example 6, and the average particle diameter, aspect ratio, and layer thickness were confirmed. It was. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 11)
A coating material was prepared by adding 30% by mass of colloidal silica to the tungsten oxide fine particle coating material obtained in Example 6. For the tungsten oxide composite paint thus obtained, a layer having a thickness of 0.3 μm was produced on glass in the same manner as in Example 6, and the average particle diameter, aspect ratio, and layer thickness were confirmed. It was. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

Example 12
To the tungsten oxide fine particle paint obtained in Example 6, 0.002% by mass of silver nitrate was added as Ag and subjected to a photoreduction treatment, and then a layer having a thickness of 0.3 μm was formed on the glass. The average particle size, aspect ratio, and layer thickness were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 6, and evaluated hydrophilicity. The evaluation results are shown in Table 1. There was no orientation, and the light transmittance was 80% or more. Further, as in Example 6, high hydrophilicity was exhibited even in a dark place, and a higher photocatalytic effect was confirmed.
Moreover, it was confirmed that it also has antibacterial properties regardless of dark places or light irradiation.
Furthermore, when this sample was applied to the lens surface of the loupe in the same manner as in the above example and the loupe was exposed to steam, the surface of the lens was uniformly wet without causing water droplets due to steam and high transparency. It was confirmed that it was not cloudy.

(Example 13)
A photocatalyst coating material was produced in the same manner as in Example 1 for the fine particles obtained in Example 2. After applying a polysiloxane paint (JSR Glassca) to an A4 size PET film as an underlayer, apply the paint to a thickness of about 10 μm with a bar coater and dry at 120 ° C. for 30 minutes to produce the applied film. did. Further, an adhesive was applied to the surface of the film opposite to the surface to which the paint was applied. This film was attached to glass for evaluation.
As a result, the hydrophilicity was the same as in Example 2. Moreover, since the film has an adhesive layer, it could be easily attached to a glass substrate.
Further, when the sample was applied to the lens surface of the loupe and exposed to steam in the same manner as in the above example, the lens surface was uniformly wet without generating water droplets due to steam and was highly transparent. It was confirmed that it was not cloudy.

(Comparative Example 2)
Using a sputtering method, a tungsten oxide film having a thickness of 0.1 μm was formed on glass, and the average particle diameter, aspect ratio, and thickness of the tungsten oxide film were confirmed. The measurement results are shown in Table 1. About the obtained film | membrane, it carried out similarly to Example 1, and evaluated hydrophilicity. The evaluation results are shown in Table 1. As a result of evaluating the orientation, the film had a crystal structure in which triclinic crystals were oriented. The light transmittance was 50%. Since the film was oriented, the hydrophilicity was low immediately after film formation and after storage in the dark. On the other hand, the contact angle was decreased by irradiation with visible light, but the hydrophilicity was insufficient. Moreover, the decomposition ability of oleic acid was low.
Furthermore, when the tungsten oxide film was formed on the lens surface and the loupe was exposed to steam, the surface of the lens produced water droplets due to the steam and clouded, and the image could not be clearly confirmed.

(Comparative Example 3)
An SiO ₂ film having a thickness of 0.5 μm was formed on glass using colloidal silica, and the average particle diameter, aspect ratio, and film thickness were confirmed. The measurement results are shown in Table 1. About the obtained surface layer, it carried out similarly to Example 1, and evaluated hydrophilicity. The evaluation results are shown in Table 1.
Immediately after the formation of the film, it showed high hydrophilicity, but adsorbed dirt in the atmosphere during storage in the dark, and the hydrophilicity decreased. Moreover, the change by light irradiation was not seen. As a matter of course, there was no ability to decompose oleic acid.
Furthermore, when the film was formed on the lens surface of the loupe and the loupe was exposed to steam in the same manner as in the above example, water droplets due to steam did not adhere to the lens surface in the initial stage. However, after that, water droplets started to adhere and clouded, and the image could not be clearly confirmed.

(Comparative Example 4)
A film having a thickness of 0.3 μm was formed on glass using an anatase-type titania sol paint using a polysiloxane resin as a binder, and the average particle diameter, aspect ratio, and thickness of the film were confirmed. The measurement results are shown in Table 1. About the obtained film | membrane, it carried out similarly to Example 1, and evaluated hydrophilicity. However, since the contact angle after the visible light irradiation of the sample after 1 month in the dark did not change, the measurement results after the ultraviolet irradiation are shown in Table 1.
The results of the oleic acid decomposition test are also shown in Table 1.
As a result, although it was low immediately after the film formation, a tendency toward hydrophilicity was observed, but dirt in the atmosphere was adsorbed during storage in the dark and the hydrophilicity was lowered. In addition, the contact angle tended to decrease after ultraviolet irradiation, and the effect of light irradiation was observed. In the oleic acid decomposition test, hydrophilicity was exhibited only under ultraviolet irradiation.
Furthermore, when a film was formed on the lens surface of the loupe by the same method as described above, and the loupe was exposed to steam, the surface of the lens initially had transparency without adhering water droplets due to steam. However, after that, water droplets adhered and clouded, and the image could not be confirmed clearly. Moreover, when the ultraviolet rays were irradiated, the hydrophilicity was restored and the water droplets spread uniformly, so that the transparency of the lens was restored.

  Further, when the surface layer prepared in Example 6 was evaluated for antibacterial properties using Staphylococcus aureus, Escherichia coli, and mold, it was confirmed that all exhibited excellent antibacterial properties. Since the lens of the present embodiment can provide a uniform film, it is transparent, is not likely to cause problems such as color unevenness visually, and is suitably used for a loupe.

Claims (11)

  The lens surface is provided with fine particles of tungsten oxide or a composite material of tungsten oxide, the average particle size of the fine particles is in the range of 1 nm to 200 nm, and the aspect ratio of the fine particles is in the range of 1 to 3.5. Loupe characterized by.   The loupe according to claim 1, wherein the layer having the fine particles has a thickness in the range of 2 nm to 50 μm.   The loupe according to claim 1 or 2, wherein the layer having the fine particles is formed on an inorganic base layer.   The loupe according to any one of claims 1 to 3, wherein the light transmittance at a wavelength of 550 nm of the layer having the fine particles is 50% or more.   The loupe according to any one of claims 1 to 4, wherein the surface having the fine particles comprises a transition metal element in a range of 0.01% by mass to 50% by mass. . In loupe of any one of claims 1 to 5, magnifying glass surfaces provided with the said particles, characterized in that it comprises a TiO ₂ in the range of 0.01% to 50% by weight. The loupe according to any one of claims 1 to 6, wherein the surface layer including the fine particles of the tungsten oxide or the tungsten oxide composite is formed on the layer including TiO _2. A loupe.   The loupe according to any one of claims 1 to 7, wherein the surface layer having the fine particles is at least one selected from Cu, Zn, and Ag in a range of 0.001% by mass to 1% by mass. A loupe characterized by comprising elements. 9. The loupe according to claim 1, wherein the surface having the fine particles comprises at least one selected from SiO ₂ , Al ₂ O ₃ , and ZrO ₂ .   The loupe according to any one of claims 1 to 9, wherein the loupe has a photocatalytic performance under visible light irradiation.   The loupe according to any one of claims 1 to 10, wherein a surface having the fine particles is formed of a film.