Patent Publication Number: US-2022214562-A1

Title: Spectacle lens and method for manufacturing spectacle lens

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of PCT International Application No. PCT/JP2020/036557 filed on Sep. 28, 2020, which was published under PCT Article 21(2) in Japanese and claims priority under 35 U.S.C. § 119(a) to Japanese Patent Application No. 2019-178134 filed on Sep. 28, 2019. Each of the above applications is hereby expressly incorporated by reference, in its entirety, into the present application. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a spectacle lens that has antibacterial and water-repellent properties on a lens surface and a method for manufacturing the same. 
     BACKGROUND ART 
     Lenses such as spectacle lenses generally have various films (layers) that cover a surface of a lens substrate (see PTL 1 to 4, which are expressly incorporated herein by reference in their entirety). 
     CITATION LIST 
     Patent Literature 
     [PTL 1] Japanese Patent Application Publication No. H9-327622 
     [PTL 2] Japanese Patent Application Publication No. 2010-101918 
     [PTL 3] Japanese Patent Application Publication No. 2010-139964 
     [PTL 4] Japanese Patent Application Publication No. 2018-159860 
     Examples of a film that covers a surface of a lens substrate include a hard coat film for preventing scratches on a lens substrate, an antireflection film for preventing light reflection on a lens surface, a water-repellent film for preventing a water mark on a lens, an anti-fog film for preventing fogging of a lens, and like. Further, a spectacle lens that is caused to have antibacterial properties on a lens surface and is particularly suitable for a user who works in a clean environment such as a medical site, and a spectacle lens that is caused to have antistatic properties on a lens surface so that adhesion of dust can be prevented are also known. 
     PTL 1 discloses an antibacterial surface coating agent containing a zeolite which is ion-substituted with silver ions while having a specific polymerizable compound as a main component. 
     PTL 2 discloses spectacles that are provided with fine particles of tungsten oxide or a composite material of tungsten oxide on a lens surface and have excellent anti-fog properties and photocatalytic properties such as antibacterial and sterilizing properties. 
     PTL 3 discloses an optical part in which an antireflection film is provided on a surface of an optical part such as a spectacle lens and a bactericidal substance such as N-(trimethoxypropyl)isothiouronium chloride is applied on the antireflection film. 
     PTL 4 discloses an optical product (a camera, a spectacle, or the like) in which a dielectric multilayer film including a low refractive index dielectric layer and a high refractive index dielectric layer is provided on a surface of a base material of a lens or the like, and a dielectric layer containing a metal ion-supporting zeolite (an antibacterial material) is disposed on an outermost layer of the dielectric multilayer film, and which provides antibacterial properties while having an optical function such as antireflection. 
     SUMMARY 
     As mentioned above, conventionally, there are lenses with antibacterial properties, but in order to for the antibacterial properties to be exhibited, it is necessary to increase a film thickness of a layer containing an antibacterial material to, for example, about 50 nm to 100 nm. In this case, if this is applied on an antireflection film of a spectacle lens, interference fringes are generated and optical characteristics are deteriorated, and thus a new antireflection film design is required, and it cannot be applied on an antireflection film of an existing design. PTL 4 describes that a dielectric multilayer film containing an antibacterial material has an optical function such as antireflection, but a film design of the dielectric multilayer film becomes considerably complicated. 
     Also, general spectacle lenses have a water-repellent film on an outermost lens surface, but in a case in which not only water-repellent properties but also antibacterial properties are imparted at the same time, it is necessary to additionally provide a layer containing the above-mentioned conventional antibacterial material on the lens surface. However, when each of these films is formed on the lens surface in order to obtain both of antibacterial and water-repellent properties, the water-repellent properties may not be obtained in a case in which the outermost lens surface is an antibacterial film. Further, in a case in which the outermost lens surface is made of a water-repellent film, sufficient antibacterial properties cannot be obtained. That is, in conventional techniques, it has been difficult to obtain both of antibacterial and water-repellent properties. 
     One aspect of the present disclosure provides for a spectacle lens in which both of excellent antibacterial properties and water-repellent properties of a lens surface can be obtained, and a method for manufacturing the same. 
     As a result of diligent studies, the present inventors have found that it becomes possible to provide a spectacle lens in which, by imparting antibacterial properties to a water-repellent film generally provided on the outermost lens surface to form a surface having both of water-repellent and antibacterial properties, both of excellent antibacterial and water-repellent properties of the lens surface can be obtained. 
     One aspect of the present disclosure relates to a spectacle lens including a coating film containing an antibacterial material and a water-repellent material on a surface of a lens substrate. 
     Also, one aspect of the present disclosure relates to a method for manufacturing a spectacle lens including forming a coating film containing an antibacterial material and a water-repellent material on a surface of a lens substrate using a vapor deposition method. 
     According to the spectacle lens of one aspect of the present disclosure, by including the coating film containing the antibacterial material and the water-repellent material on the surface of the lens substrate, both of excellent antibacterial and water-repellent properties of a lens surface can be obtained. Also, since such high antibacterial and water-repellent properties can be obtained with the same film (the above coating film), antireflection properties of an antireflection film is not affected even in a case in which the antireflection film is provided under the coating film, and for that reason, it can be easily applied on the antireflection film of an existing design. That is, it is possible to impart both of excellent antibacterial and water-repellent properties to the lens surface while the antireflection properties of an existing product is maintained. 
     Further, the method for manufacturing a spectacle lens according to one aspect of the present disclosure is suitable for manufacturing the above-mentioned spectacle lens. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a cross-sectional view of one embodiment of a spectacle lens according to one aspect of the present disclosure. 
         FIG. 2  is a schematic diagram for explaining a coating film forming method using a vapor deposition method. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments for implementing the present disclosure will be described below with reference to the drawings. However, the present disclosure is not limited to the forms shown in the drawings. 
       FIG. 1  is a cross-sectional view of one embodiment of a spectacle lens according to one aspect of the present disclosure. 
     Configuration of Spectacle Lens 
     A spectacle lens  1  of the present embodiment is a spectacle lens in which a hard coat film for protecting a lens surface from scratches or the like, an antireflection film for preventing light reflection on the lens surface, and the like are formed on a spectacle lens substrate. 
     Specifically explaining with reference to  FIG. 1 , the spectacle lens  1  of the present embodiment has a hard coat film  12  on one surface  11   a  (for example, a surface on an object side) of a lens substrate  11 , and an antireflection film  13  on the hard coat film  12 . The antireflection film  13  is a film in which a low refractive index layer  13 L and a high refractive index layer  13 H are alternately laminated. Also, in the present embodiment, the antireflection film  13  has a coating film  14  containing an antibacterial material and a water-repellent material. Details of a configuration of the coating film  14  will be described later. 
     The lens substrate  11 , the hard coat  12 , and the antireflection film  13  will be described below in order. 
     Lens Substrate 
     The lens substrate  11  in the present embodiment has a first main surface (an object side surface), a second main surface (an eyeball side surface), and an edge surface (edge portion). 
     A material of the lens substrate  11  may be plastic or inorganic glass. For example, as the lens substrate  11 , various plastic base materials usually used for plastic lenses can be used. A plastic lens substrate can be manufactured by injecting a lens monomer into a lens forming mold and performing a curing treatment. 
     The lens monomer is not particularly limited, and various monomers usually used for manufacturing plastic lenses can be used. For example, a monomer having a benzene ring, a naphthalene ring, an ester bond, a carbonate bond, a urethane bond, or the like in a molecule can be used. Further, a compound containing sulfur and halogen elements can also be used, and in particular, a compound having a nuclear halogen-substituted aromatic ring can also be used. The lens monomer can be produced by using one kind or two or more kinds of monomers having the above functional groups. For example, styrene, divinylbenzene, phenyl (meth)acrylate, benzyl(meth)acrylate, naphthyl (meth)acrylate, methyl (meth)acrylate, diethylene glycol bisallyl carbonate, diallyl (iso)phthalate, dibenzyl itaconate, dibenzyl fumarate, chlorostyrene, nuclear halogen-substituted styrene, nuclear halogen-substituted phenyl (meth)acrylate, nuclear halogen-substituted benzyl (meth)acrylate, tetrabromobisphenol A (di) (meth)acrylate derivatives, tetrabromobisphenol A diallyl carbonate derivatives, diortho chloro benzyl itaconate, diortho chloro benzyl fumarate, diethylene glycol bis(ortho chloro benzyl) fumarate, (di)ethylene glycol di(meth)acrylate, glycidyl methacrylate, xylylene diisocyanate, reaction products of polyfunctional isocyanates such as hexamethylene diisocyanate, reaction products of monohydroxyacrylates of nuclear halogen-substituted phenol derivatives and polyfunctional isocyanates, reaction products of monohydroxyacrylate and polyfunctional isocyanate of nuclear halogen-substituted biphenyl derivatives, reaction products of xylene diisocyanate and polyfunctional mercaptan, reaction products of glycidyl methacrylate and polyfunctional methacrylate, etc., and mixtures thereof can be mentioned. As a material of the lens substrate, for example, polyurethane-based materials such as polythiourethane resin and polyurethane resin, epithio-based materials such as polysulfide resin, polycarbonate-based materials, diethylene glycol bisallyl carbonate-based materials, or the like can be mentioned as being suitable. 
     For the lens substrate  11 , a colorless material is usually used, but a colored one can be used as long as transparency is not impaired. 
     A refractive index of the lens substrate  11  is, for example, 1.50 or more and 1.74 or less. 
     The lens substrate  11  may be either a finished lens or a semi-finish lens. 
     A surface shape of the lens substrate  11  is not particularly limited and may be a flat surface, a convex surface, a concave surface, or the like. 
     The spectacle lens  1  of the present embodiment may be any of a single focus lens, a multifocal lens, a progressive power lens, and the like. In the progressive power lens, usually, a near part region (a near part) and a progressive part region (an intermediate region) are included in a lower region, and a distance part region (a distance part) is included in an upper region. 
     Hard Coat Film 
     The hard coat film  12  can impart scratch resistance to the plastic lens. 
     A method for applying a curable composition to a surface of the lens substrate  11  using a spin coating method or the like to cure a coating film is a general method for forming the hard coat film  12 . The curing treatment is performed by heating, light irradiation, or the like, depending on a type of the curable composition. 
     For such a curable composition, for example, a photocurable silicone composition containing a silicone compound that produces a silanol group upon irradiation with ultraviolet rays and an organopolysiloxane having a halogen atom that undergoes a condensation reaction with a silanol group or a reactive group such as an amino group as main components, an acrylic UV curable monomer composition, an inorganic fine particle-containing thermosetting composition in which inorganic fine particles such as SiO 2  and TiO 2  are dispersed in a silane compound or a silane coupling agent having a polymerizable group such as a vinyl group, an allyl group, an acrylic group or a methacrylic group and a hydrolyzable group such as a methoxy group, and the like can be mentioned as being suitable. A composition of the hard coat film  12  is selected in accordance with the material of the lens substrate  11 . In addition, a refractive index of the hard coat film  12  is, for example, 1.45 or more and 1.74 or less. 
     Antireflection Film 
     The antireflection film  13  usually has a multilayer structure in which layers having different refractive indexes are laminated and is a film that prevents light reflection caused by an interference action. Examples of a material of the antireflection film  13  include inorganic substances such as SiO 2 , SiO, ZrO 2 , TiO 2 , TiO, Ti 2 O 3 , Ti 2 O 5 , Nb 2 O 5 , Al 2 O 3 , Ta 2 O 5 , CeO 2 , MgO, Y 2 O 3 , SnO 2 , MgF 2 , and WO 3 , and these can be used alone or in combination of two or more. 
     An example of such an antireflection film  13  is a multilayer structure in which the low refractive index layer  13 L and the high refractive index layer  13 H are laminated in multiple layers. A refractive index of the low refractive index layer  13 L is, for example, 1.35 to 1.80 at a wavelength of 500 to 550 nm. A refractive index of the high refractive index layer  13 H is, for example, 1.90 to 2.60 at a wavelength of 500 to 550 nm. 
     The low refractive index layer  13 L is made of, for example, silicon dioxide (SiO 2 ) having a refractive index of about 1.43 to 1.47. Further, the high refractive index layer  13 H is made of a material having a higher refractive index than the low refractive index layer  13 L and is composed of, for example, a metal oxide such as niobium oxide (Nb 2 O 5 ), tantalum pentoxide (Ta 2 O 5 ), zirconium oxide (ZrO 2 ), yttrium oxide (Y 2 O 3 ), and aluminum oxide (Al 2 O 3 ) in an appropriate ratio. 
     In a case in which the material of the antireflection film  13  is an inorganic substance such as a metal oxide as described above, as a film forming method thereof, for example, a vacuum vapor deposition, an ion plating method, a sputtering method, a CVD method, a method of depositing using a chemical reaction in a saturated solution, or the like can be adopted. 
     Next, the coating film containing the antibacterial material and the water-repellent material will be described in detail. 
     As described above, the spectacle lens  1  of the present embodiment has the coating film  14  containing the antibacterial material and the water-repellent material on the surface (for example, the outermost surface) of the lens substrate  11 . 
     For the antibacterial material, for example, silver (Ag) particles may be used. Silver particles exhibit good antibacterial properties in, for example, ultraviolet light and visible light regions, and, by having the coating film  14  containing silver particles on the surface of the lens substrate  11 , it is possible to impart excellent antibacterial properties to the lens surface. 
     In a case in which the coating film  14  is formed by the vapor deposition method, which will be described later, a solid content weight of the silver particles on a sintered filter (chip), which will be described later, may be 0.85 mg (an injection amount of a silver particle aqueous dispersion (a concentration of 5,000 ppm) of 0.05 ml, which will be described later) or more, and may be 1.45 mg (an injection amount of a silver particle aqueous dispersion (a concentration of 5,000 ppm) of 0.1 ml, which will be described later) or more. In addition, an upper limit of the solid content weight of the silver particles is not particularly limited, but is, for example, 17.2 mg (an injection amount of a silver particle aqueous dispersion (a concentration of 5,000 ppm) of 1.0 ml, which will be described later) or less. Here, the unit ppm is based on weight. 
     The silver particles may be particles having a particle size smaller than a film thickness of the coating film  14 . If particles having a particle size larger than the film thickness of the coating film  14  are included, protrusions may be formed on a surface of the coating film  14  and optical properties of the lens surface may be deteriorated. 
     As described above, the silver particles may have a particle size smaller than that of the coating film  14 . Considering the case in which the film thickness of the coating film  14  is 5 nm or more and 30 nm or less as described later, the silver particles may have a particle size of 1 nm or more and 10 nm or less, and particularly may have 1 nm or more and 5 nm or less. 
     Further, since such silver particles having a particle size of nanometer size can be melted at a low temperature, they are suitable for forming the coating film  14  containing the antibacterial material and the water-repellent material using a vapor deposition method as described later. 
     Further, as the water-repellent material, any substance that can make the surface of the coating film  14  a water-repellent region can be used without particular limitation. For the water-repellent material, for example, a fluorine-based substance can be used. For such a fluorine-based substance, for example, metaxylene hexafluoride (C 6 H 4 (CF 3 ) 2 ) or the like can be used. 
     Further, for the fluorine-based substance, for example, a fluorine-containing silane compound represented by the following general formula (1) can be used. 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     Rf in the general formula (1) is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms and may be CF 3 —, C 2 F 5 —, and C 3 F 7 —. R 1  is a hydrolyzable group, and for example, may be halogen atoms, —OR 3 , —OCOR 3 , —OC(R 3 )═C(R 4 ) 2 , —ON═C(R 3 ) 2 , or —ON═CR 5 . It may be a chlorine atom, —OCH 3 , or —OC 2 H 5 . Here, R 3  is an aliphatic hydrocarbon group or an aromatic hydrocarbon group, R 4  is a hydrogen atom or a lower aliphatic hydrocarbon group, and R 5  is a divalent aliphatic hydrocarbon group having 3 to 6 carbon atoms. R 2  is a hydrogen atom or a monovalent organic group. The monovalent organic group may be an inert group. The monovalent organic group may be a monovalent hydrocarbon group having 1 to 4 carbon atoms. X is an iodine atom or a hydrogen atom, and Y is a hydrogen atom or a lower alkyl group. Z is a fluorine atom or a trifluoromethyl group. Symbols a, b, c, and d are independently integers in the range of 0 to 200, and may be integers in the range of 1 to 50. Symbol e is 0 or 1. Symbols m and n are independently integers in the range of 0 to 2, and may be 0. Symbol p is an integer of 1 or more, and may be an integer in the range of 1 to 10. 
     Also, a molecular weight (a weight average molecular weight Mw) of the above compound is not particularly limited, and for example, may be 5×10 2  to 1×10 5 , and may be 5×10 2  to 1×10 4 . 
     Further, the fluorine-containing silane compound represented by the above general formula (1) may be a compound represented by the following general formula (2). 
     
       
         
         
             
             
         
       
     
     R 1 , Y, and m in the general formula (2) are synonymous with the general formula (1). Symbol q is an integer in the range of 1 to 50, and r is an integer in the range of 1 to 10. 
     Also, since the water-repellent material can be used without particular limitation as long as it is a substance that makes the surface of the coating film  14  a water-repellent region, it is not limited to the above-exemplified substance. 
     The film thickness of the coating film  14  containing the antibacterial material (for example, silver particles) and the water-repellent material (for example, a fluorine-based substance) may be as thin as possible so that deterioration of the optical characteristics of the lens surface (occurrence of interference fringes, etc.) can be inhibited. From such a viewpoint, the film thickness of the coating film  14  may be in the range of 5 nm or more and 30 nm or less. Particularly, it may be in the range of 10 nm or more and 15 nm or less. In the spectacle lens, both of excellent antibacterial and water-repellent properties can be obtained even when the coating film  14  containing the antibacterial material and the water-repellent material is, for example, a thin film having a film thickness of 30 nm or less. 
     In the spectacle lens  1  of the present embodiment, the surface of the coating film  14  on a side opposite to the lens substrate  11  side has a contact angle with water of, for example, 100° or more and 120° or less, and the lens surface can have good water-repellent properties. 
     Further, as shown in  FIG. 1 , the spectacle lens  1  of the present embodiment has the antireflection film  13  below the coating film  14 . According to the present embodiment, since the film thickness of the coating film  14  that imparts the antibacterial properties and the water-repellent properties on the lens surface can be reduced to, for example, 30 nm or less, it is possible to inhibit an influence on the antireflection properties of the antireflection film  13 . For that reason, it can be easily applied on the antireflection film of an existing design. 
     Also, in the embodiment of  FIG. 1 , an aspect in which the coating film  14  is provided on one surface  11   a  (for example, the surface on the object side) of the lens substrate  11  is illustrated. The spectacle lens according to one aspect of the present disclosure is not limited thereto, and an aspect having the coating film  14  not only on the first main surface (object side surface) of the lens substrate  11 , but also on the other second main surface (eyeball side surface) may also be applicable. 
     As described above, according to the spectacle lens  1  of the present embodiment, by having the coating film  14  containing the antibacterial material and the water-repellent material on the surface of the lens substrate  11 , both of excellent antibacterial and water-repellent properties of the lens surface can be obtained. In addition, such high antibacterial and water-repellent properties can be obtained with the same film (the above coating film  14 ). Further, even in a case in which the antireflection film  13  is provided below the coating film  14 , it is possible not to influence the antireflection properties of the antireflection film  13 , and for that reason, it can be easily applied on the antireflection film of the existing design. That is, it is possible to impart both of excellent antibacterial and water-repellent properties to the lens surface while maintaining the antireflection properties of an existing product. 
     Next, a method for manufacturing the spectacle lens  1  of the present embodiment described above will be described. According to one aspect of the present disclosure, a method for manufacturing a spectacle lens suitable for manufacturing the spectacle lens is provided. The method for manufacturing a spectacle lens according to one aspect of the present disclosure includes forming a coating film containing an antibacterial material and a water-repellent material on a surface of a lens substrate using a vapor deposition method. 
     As shown in  FIG. 1  described above, the spectacle lens  1  of the present embodiment has the hard coat film  12  on one surface  11   a  of the lens substrate  11 , the antireflection film  13  on the hard coat film  12 , and the coating film  14  containing an antibacterial material and a water-repellent material on the antireflection film  13 . The film forming method of the hard coat film  12  and the antireflection film  13  has already been described. 
     A method for forming the coating film  14  will be described below. 
     In order to manufacture the spectacle lens according to one aspect of the present disclosure, the method for forming the coating film  14  containing the antibacterial material and the water-repellent material using a vapor deposition method can be applied. 
       FIG. 2  is a schematic diagram for explaining a coating film forming method using a vapor deposition method. Also, in  FIG. 2 , illustration of the hard coat film  12  and the antireflection film  13  is omitted. 
     In a vacuum chamber (not shown), for example, a sintered filter  2 , into which the antibacterial material and the water-repellent material are injected and which is placed on a molybdenum boat (not shown), is heated by a heating means  3  to simultaneously heat and evaporate the antibacterial material and the water-repellent material to cause them to adhere to the surface of the lens substrate  11 , thereby forming the coating film  14  containing the antibacterial material and the water-repellent material. 
     The sintered filter  2  into which the antibacterial material and the water-repellent material are injected is prepared as follows, for example. 
     A water dispersion containing the antibacterial material (for example, silver particles) and a coating liquid containing the water-repellent material (for example, a fluorine-based substance) are injected into the sintered filter  2  and dried, for example, at 50° C. for 1 hour to leave solid contents of the antibacterial material and the water-repellent material in the sintered filter  2 . 
     For the heating means  3 , for example, a halogen heater or the like can be used. 
     In a case in which silver particles are used as the antibacterial material and, for example, a fluorine-based substance is used for the water-repellent material, it is assumed that the coating film  14  that has adhered to and has been formed on the surface of the lens substrate  11  using the above vapor deposition method has silver particles serving as the antibacterial material present in the coating film (a water-repellent film made of the water-repellent material). 
     A pressure in the vacuum chamber at the time of film formation varies depending on types of the antibacterial material and the water-repellent material used and, although it cannot be said unconditionally, it may be 2×10 −2  Pa or less, for example. 
     In addition, a heating temperature at the time of film formation varies depending on types of the antibacterial material and the water-repellent material used and, although it cannot be said unconditionally, the temperature may be appropriately adjusted in the range of, for example, 100° C. or higher and 750° C. or lower. Here, the heating temperature at the time of film formation is an internal atmospheric temperature of a device for performing the film formation and can be, for example, the internal atmospheric temperature of the vacuum chamber. 
     Further, it is possible to adjust a film thickness of the formed coating film  14  by appropriately adjusting a film forming time. 
     As described above, the coating film  14  containing the antibacterial material and the water-repellent material is formed on the lens surface, and the spectacle lens  1  of the present embodiment is completed. 
     As described above, the method for manufacturing a spectacle lens according to one aspect of the present disclosure is suitable for manufacturing the above-mentioned spectacle lens according to one aspect of the present disclosure. 
     EXAMPLES 
     The present disclosure will be described in more detail below with reference to examples. However, the present disclosure is not limited to the embodiments shown in the examples. 
     Example 1 
     A hard coat liquid containing inorganic oxide particles and a silicon compound was applied to the entire surface (a convex surface) of one surface of a spectacle lens substrate manufactured by a monomer for spectacle lenses (a trade name “MR8” manufactured by Mitsui Chemicals, Inc.) by spin coating and cured by heating at 100° C. for 60 minutes, thereby forming a single-layer hard coat film with a thickness of 3 μm. 
     Next, the spectacle lens on which the hard coat film was formed was placed in a vapor deposition device, and an antireflection film in which SiO 2 —ZrO 2 —SiO 2  layers were alternately laminated was formed on the entire surface of the hard coat film using a vacuum vapor deposition method. 
     Preparation of Antibacterial Material-Containing Liquid and Water-Repellent Material-Containing Liquid 
     As an antibacterial material-containing liquid, an aqueous dispersion (a concentration (content) of 5,000 ppm) of silver particles (a particle size of 5 nm) was prepared. 
     Further, as a water-repellent material-containing liquid, a coating liquid containing metaxylene hexafluoride as the fluorine-based substance was prepared. 
     Formation of Coating Film 
     0.5 ml of a silver particle aqueous dispersion was injected into a surface of a disk-shaped sintered filter (material: SUS) having a diameter of φ18 mm and dried in a drying oven at 50° C. for 1 hour. An Ag solid content weight after drying was 0.0077 g. Next, similarly, 0.25 ml of a coating liquid containing the above-mentioned fluorine-containing silane compound was injected onto the surface of the sintered filter and dried in a drying oven at 50° C. for 1 hour. 
     As shown in  FIG. 2  described above, in a vacuum chamber, the sintered filter into which the antibacterial material and the water-repellent material prepared as described above were injected was placed on a molybdenum boat and heated by a heating means. A halogen heater was used for the heating means. A heating temperature at the time of film formation was adjusted to 650° C. Also, a pressure in the vacuum chamber at the time of film formation was 2×10 −2  Pa or less. 
     Thus, the antibacterial material and the water-repellent material were heated at the same time, evaporated, and caused to adhere to the surface of the spectacle lens, thereby forming a coating film having a film thickness of 15 nm containing the antibacterial material and the water-repellent material. Further, a film thickness of the formed coating film was adjusted by appropriately adjusting a film forming time. 
     As described above, the coating film containing the antibacterial material and the water-repellent material was formed on the lens surface, and the spectacle lens of Example 1 was produced. 
     Example 2 
     A coating film having a film thickness of 15 nm was formed on a surface of a spectacle lens in the same manner as in Example 1 except that an amount of the aqueous dispersion of silver particles injected into the sintered filter was 1.0 ml, and thus a spectacle lens of Example 2 was produced. 
     Example 3 
     A coating film having a film thickness of 15 nm was formed on a surface of a spectacle lens in the same manner as in Example 1 except that an injection amount of the aqueous dispersion of silver particles into the sintered filter was 0.1 ml, and thus a spectacle lens of Example 3 was produced. 
     Example 4 
     A coating film having a film thickness of 15 nm was formed on a surface of a spectacle lens in the same manner as in Example 1 except that an amount of the aqueous dispersion of silver particles injected into the sintered filter was 0.05 ml, and thus a spectacle lens of Example 4 was produced. 
     Example 5 
     A coating film having a film thickness of 15 nm was formed on a surface of a spectacle lens in the same manner as in Example 1 except that the silver particles used as the antibacterial material had a particle size of 3 nm, and thus a spectacle lens of Example 5 was produced. 
     Example 6 
     A coating film having a film thickness of 15 nm was formed on a surface of a spectacle lens in the same manner as in Example 1 except that the silver particles used as the antibacterial material had a particle size of 8 nm, and thus a spectacle lens of Example 6 was produced. 
     Example 7 
     A spectacle lens of Example 7 was produced in the same manner as in Example 1 except that the film thickness of the coating film formed on the surface of the spectacle lens was 30 nm. 
     Example 8 
     A spectacle lens of Example 8 was produced in the same manner as in Example 1 except that the film thickness of the coating film formed on the surface of the spectacle lens was 10 nm. 
     Example 9 
     A spectacle lens of Example 9 was produced in the same manner as in Example 1 except that the film thickness of the coating film formed on the surface of the spectacle lens was 5 nm. 
     The following evaluation tests were performed on each of the spectacle lenses of Examples 1 to 9 obtained as described above. The results are summarized and shown in Table 1 below. 
     Antibacterial Properties 
     Antibacterial properties was evaluated in accordance with JIS Z 2801: 2012. Also, a spectacle lens in which the above coating film was not formed on the lens surface was used as a reference sample. 
     After 50 mm×50 mm test pieces (the spectacle lenses of each of the above examples and the above reference sample) were placed in a sterilized petri dish, 0.4 mL of a bacterial solution containing 1.0×10 5  to 4.0×10 5  test bacteria ( Staphylococcus aureus  or  Escherichia coli ) was dropped onto a center of each sample and covered with a polyethylene film cut into 40 mm×40 mm. After this petri dish was cultured at a relative humidity of 90% or more for 24 hours, a viable cell count per 1 cm 2  was measured, and the following antibacterial activity values were calculated. 
     Antibacterial activity value=Ut−At≥2.0
 
Ut: Average value of logarithmic number of viable cells per 1 cm 2  after 24-hour culture of unprocessed test piece (reference sample)
 
At: Average value of logarithmic number of viable cells per 1 cm 2  after 24-hour culture of antibacterial processed test piece (example sample)
 
     The criteria for determining the antibacterial properties are as follows. 
     ⊚: Antibacterial activity value is 4.0 or more
 
○: Antibacterial activity value is 2.5 or more and less than 4.0
 
Δ: Antibacterial activity value is 2.0 or more and less than 2.5
 
x: Antibacterial activity value is less than 2.0
 
     Water-Repellent Properties 
     A contact angle of a surface of the coating film (a surface opposite to the lens substrate side) with respect to water was measured, and the water-repellent properties of the lens surface was evaluated. 
     The criteria for determining the water-repellent properties are as follows. 
     ○: Contact angle with water is 100° or more and 120° or less
 
Δ: Contact angle with water is 95° or more and less than 100°
 
x: Contact angle with water is less than 95°
 
     
       
         
           
               
               
               
               
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                   
                 Injection 
                 Film 
                   
                   
                   
               
               
                   
                 Ag 
                 amount of 
                 thickness 
                 Antibacterial 
                 Antibacterial 
                 Water- 
               
               
                   
                 particle 
                 Ag dispersion 
                 of coating 
                 property 
                 property 
                 repellent 
               
               
                   
                 size (nm) 
                 (ml) 
                 film (nm) 
                 ( Staphylococcus ) 
                 ( Escherichia coli ) 
                 property 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Example 1 
                 5 
                 0.5 
                 15 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 2 
                 5 
                 1.0 
                 15 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 3 
                 5 
                 0.1 
                 15 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 4 
                 5 
                 0.05 
                 15 
                 ⊚ 
                 Δ 
                 ⊚ 
               
               
                 Example 5 
                 3 
                 0.5 
                 15 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 6 
                 8 
                 0.5 
                 15 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 7 
                 5 
                 0.5 
                 30 
                 ⊚ 
                 ⊚ 
                 ⊚ 
               
               
                 Example 8 
                 5 
                 0.5 
                 10 
                 ⊚ 
                 ⊚ 
                 ◯ 
               
               
                 Example 9 
                 5 
                 0.5 
                 5 
                 ◯ 
                 Δ 
                 ◯ 
               
               
                   
               
            
           
         
       
     
     In addition, the following durability evaluations were performed on each of the spectacle lenses of Examples 1 to 9 newly produced in exactly the same manner as above, and the results were summarized and shown in Table 2 below. 
     Durability Evaluation 
     After the surface of the coating film of each spectacle lens was rubbed with a lens-cleaning paper (Dusper K3 (trade name) manufactured by Ozu Corporation) reciprocating 600 times with a load of 2 kg, the evaluation tests of the antibacterial properties and the water-repellent properties were performed. A test method and determination criteria are the same as above. In addition, this lens-cleaning paper is generally used as a cleaning paper for optical lenses and the like. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 Antibacterial 
                 Antibacterial 
                 Water- 
               
               
                   
                 property 
                 property 
                 repellent 
               
               
                   
                 ( Staphylococcus ) 
                 ( Escherichia coli ) 
                 property 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 Example 1 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 2 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 3 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 4 
                 Δ 
                 Δ~X 
                 ◯ 
               
               
                 Example 5 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 6 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 7 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 8 
                 ⊚ 
                 Δ 
                 ◯ 
               
               
                 Example 9 
                 Δ 
                 Δ~X 
                 Δ 
               
               
                   
               
            
           
         
       
     
     Evaluation Results 
     As can be seen from the results in Table 1 above, all of the spectacle lenses of the examples can obtain both of excellent antibacterial and water-repellent properties on the lens surface. In addition, such high antibacterial and water-repellent properties can be obtained with the same film (the coating film). Further, high antibacterial and water-repellent properties can be obtained even with a thin film having a film thickness of 30 nm or less. 
     Also, in particular, the film thickness of the coating film may be in the range of 10 nm to 30 nm, and may be in the range of 10 nm to 15 nm. If an initial film thickness of the coating film is too thin (for example, about 5 nm), the antibacterial properties after wear of the lens surface tends to deteriorate (Table 2). 
     Finally, the above-described aspects will be summarized. 
     According to one aspect, a spectacle lens having a coating film containing an antibacterial material and a water-repellent material on a surface of a lens substrate is provided. 
     In one form, the antibacterial material can be silver particles. 
     In one form, the silver particles can be particles whose particle size is smaller than a film thickness of the coating film. 
     In one form, the silver particles can have a particle size of 1 nm or more and 10 nm or less. 
     In one form, the water-repellent material can be a fluorine-based substance. 
     In one form, the film thickness of the coating film can be 5 nm or more and 30 nm or less. 
     In one form, a surface of the coating film on a side opposite to the lens substrate side can have a contact angle with respect to water of 100° or more and 120° or less. 
     In one form, the spectacle lens can have an antireflection film below the coating film. 
     According to one aspect, a method for manufacturing a spectacle lens which includes forming a coating film containing an antibacterial material and a water-repellent material on a surface of a lens substrate using a vapor deposition method is provided. 
     In one form, forming the coating film containing the antibacterial material and the water-repellent material using a vapor deposition method can be simultaneously heating and evaporating the antibacterial material and the water-repellent material to cause them to adhere to the surface of the lens substrate in a vacuum chamber, thereby forming the coating film containing the antibacterial material and the water-repellent material. 
     In one form, a pressure in the vacuum chamber can be 2×10 −2  Pa or less. 
     In one form, a heating temperature can be 100° C. or higher and 750° C. or lower. 
     In one form, the antibacterial material can be silver particles. 
     The various forms described in the present specification can be combined in any combination of two or more. 
     The embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The scope of the present disclosure is shown by the scope of claims rather than the above description and is intended to include all modifications within the meaning and scope of the claims. 
     Reference Signs List 
     
         
           1  Spectacle lens 
           11  Lens substrate 
           12  Hard coat film 
           13  Antireflection film 
           13 H High refractive index layer 
           13 L Low refractive index layer 
           14  Coating film 
           2  Sintered filter 
           3  Heating means