Eyeglass lens, method for manufacturing same, and eyeglasses

Abstract

Provided is an eyeglass lens that includes a lens base material and a multilayer film located on at least one surface of the lens base material, and further includes an undercoat layer between the lens base material and the multilayer film, wherein the thickness of the undercoat layer is 400.0 nm or greater, and the indentation hardness value measured at the surface of the undercoat layer for a load of 0.3 mN is greater than the indentation hardness value measured at the surface of the multilayer film for a load of 0.3 mN.

Description

Eyeglass lenses, their manufacturing method, and eyeglasses

[0001] The present invention relates to a spectacle lens, a method for manufacturing the same, and spectacles.

[0002] Spectacle lenses are generally manufactured by forming a functional film on the surface of a lens substrate to provide the spectacle lens with a desired function. As such a functional film, a multilayer film is provided on the surface of the lens substrate (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2015-007695

[0004] Paragraph 0022 of Patent Document 1 describes disposing a functional thin film as an underlayer between the lens substrate and the multilayer film.

[0005] One of the desired properties of spectacle lenses is excellent scratch resistance. However, according to the investigations of the present inventors, spectacle lenses having an underlayer between the lens substrate and the multilayer film tend to have poor scratch resistance.

[0006] An object of one aspect of the present invention is to provide a spectacle lens having an underlayer between a lens substrate and a multilayer film, which has excellent scratch resistance.

[0007] As a result of extensive research, the present inventors have newly discovered that spectacle lenses having an undercoat layer, which will be described in detail below, can exhibit excellent scratch resistance.

[0008] That is, one aspect of the present invention is as follows. [1] A spectacle lens comprising a lens substrate and a multilayer film located on at least one surface of the lens substrate, further comprising an underlayer between the lens substrate and the multilayer film, wherein the underlayer has a thickness of 400.0 nm or more, and the indentation hardness measured at the surface of the underlayer under a load of 0.3 mN is greater than the indentation hardness measured at the surface of the multilayer film under a load of 0.3 mN. [2] The spectacle lens according to [1], wherein the underlayer is an inorganic layer. [3] The spectacle lens according to [1] or [2], wherein the multilayer film comprises one or more high-refractive-index layers and one or more low-refractive-index layers, and at least one of the high-refractive-index layers has a refractive index of 2.00 or more and 2.40 or less. [4] The spectacle lens according to any of [1] to [3], wherein the multilayer film comprises one or more high-refractive-index layers and one or more low-refractive-index layers, and at least one of the low-refractive-index layers has a refractive index of 1.44 or more and 1.49 or less. [5] The spectacle lens according to [1], wherein the underlayer is an inorganic layer, the multilayer film includes one or more high-refractive-index layers and one or more low-refractive-index layers, at least one of the high-refractive-index layers having a refractive index of 2.00 or more and 2.40 or less, and at least one of the low-refractive-index layers having a refractive index of 1.44 or more and 1.49 or less. [6] A method for manufacturing the spectacle lens according to any of [1] to [5], comprising forming the underlayer by performing sputtering using a metal target and irradiating the metal film formed by sputtering with one or more ions selected from the group consisting of oxygen ions and nitrogen ions one or more times. [7] The spectacle lens according to [6], wherein the metal target is a Si target. [8] The spectacle lens according to [6], wherein the ion irradiation is performed using an ion gun. [9] Eyeglasses comprising the spectacle lens according to any of [1] to [5].

[0009] According to one aspect of the present invention, it is possible to provide a spectacle lens having an underlayer between a lens substrate and a multilayer film, which has excellent scratch resistance. Also, according to another aspect of the present invention, it is possible to provide a method for manufacturing the spectacle lens, and spectacles including the spectacle lens.

[0010] [Eyeglass Lens] Hereinafter, an eyeglass lens according to one aspect of the present invention will be described in further detail.

[0011] <Lens Substrate> The lens substrate of the spectacle lens can be a plastic lens substrate or a glass lens substrate. The glass lens substrate can be, for example, a lens substrate made of inorganic glass. As the lens substrate, a plastic lens substrate is preferred from the viewpoints of light weight and break resistance. Examples of plastic lens substrates include (meth)acrylic resins, styrene resins, polycarbonate resins, allyl resins, allyl carbonate resins such as diethylene glycol bisallyl carbonate resin (CR-39), vinyl resins, polyester resins, polyether resins, urethane resins obtained by reacting an isocyanate compound with a hydroxy compound such as diethylene glycol, thiourethane resins obtained by reacting an isocyanate compound with a polythiol compound, and cured products (generally referred to as transparent resins) obtained by curing a curable composition containing a (thio)epoxy compound having one or more disulfide bonds in the molecule. The curable composition can also be referred to as a polymerizable composition. The lens substrate can contain known additives. One example of an additive is an ultraviolet absorber. A lens substrate containing an ultraviolet absorber can reduce the amount of ultraviolet light that enters the object-side surface and then enters the eyes of the spectacle wearer.

[0012] The lens substrate may be either undyed (colorless lens) or dyed (dyed lens). The refractive index of the lens substrate may be, for example, approximately 1.50 to 1.76. However, the refractive index of the lens substrate is not limited to the above range, and may be within the above range or may be above or below the above range. Furthermore, the lens substrate may be a lens with refractive power (so-called prescription lens) or a lens without refractive power (so-called non-prescription lens).

[0013] The spectacle lenses can be various types of lenses, such as single-vision lenses, multifocal lenses, and progressive-power lenses. The type of lens is usually determined by the surface shapes of both sides of the lens substrate. The surface of the lens substrate may be convex, concave, or flat. In ordinary lens substrates and spectacle lenses, the object-side surface is convex and the eyeball-side surface is concave. However, the present invention is not limited to this. The "object-side surface" refers to the surface that faces the object when spectacles equipped with the spectacle lenses are worn by a wearer. The "eyeball-side surface" refers to the opposite surface, i.e., the surface that faces the eyeball when spectacles equipped with the spectacle lenses are worn by a wearer.

[0014] <Underlayer> The underlayer can be formed on the surface of the lens substrate, or can be formed on the surface of a layer provided on the lens substrate. Examples of layers that can be provided on the lens substrate include a photochromic layer.

[0015] From the viewpoint of improving scratch resistance, the thickness of the underlayer of the above-mentioned spectacle lens is 400.0 nm or more, preferably 410.0 nm or more, and more preferably 420.0 nm or more, 430.0 nm or more, 440.0 nm or more, and 445.0 nm or more in that order. From the viewpoint of thinning the spectacle lens, the thickness of the underlayer is preferably 3000.0 nm or less, and more preferably 2500.0 nm or less.

[0016] The "film thickness" referred to in this specification is a physical film thickness. The film thickness can be determined by a known film thickness measurement method. For example, the film thickness can be determined by converting the optical film thickness measured by an optical film thickness measurement device into a physical film thickness.

[0017] In the above-described spectacle lens, the indentation hardness measured at the surface of the underlayer under a load of 0.3 mN is greater than the indentation hardness measured at the surface of the multilayer film under a load of 0.3 mN. This can also contribute to improving the scratch resistance of the spectacle lens.

[0018] In the present invention and this specification, the indentation hardness measured on the surface of the primer layer is the indentation hardness measured on the surface of the primer layer exposed by removing a layer above the primer layer to be measured from the spectacle lens using a known method. The indentation hardness measured on the surface of a multilayer film is the indentation hardness measured on the surface of the outermost layer of the multilayer film when the outermost layer of the multilayer film is the outermost layer of the spectacle lens. When other layers are stacked on the multilayer film, the indentation hardness is the indentation hardness measured on the surface of the outermost layer of the multilayer film after removing the other layers from the spectacle lens using a known method. In the present invention and this specification, the indentation hardness is a value measured at a load of 0.3 mN according to the method described in ISO 14577-1 / JIS Z 2255:2003. Hereinafter, "the indentation hardness measured on the surface of the underlayer at a load of 0.3 mN" will also be referred to as "underlayer indentation hardness," and "the indentation hardness measured on the surface of the multilayer film at a load of 0.3 mN" will also be simply referred to as "multilayer film indentation hardness."

[0019] From the viewpoint of further improving the scratch resistance of the spectacle lens, the difference between the value of the indentation hardness of the primer layer and the value of the indentation hardness of the multilayer film (primer layer indentation hardness - multilayer film indentation hardness) is preferably 0.50 GPa or more, more preferably 1.00 GPa or more, and even more preferably 1.50 GPa or more. The difference can be, for example, 5.00 GPa or less or 3.00 GPa or less, but from the viewpoint of improving the scratch resistance of the spectacle lens, it may exceed the values ​​exemplified here. The indentation hardness of the primer layer can be, for example, 3.00 GPa or more and 6.00 GPa or less, but is not limited to the range exemplified here.

[0020] As the underlayer, an inorganic layer is preferred because it allows dry film formation. In the present invention and this specification, an "inorganic layer" refers to a layer containing an inorganic substance, preferably a layer containing an inorganic substance as a main component. Here, the "main component" refers to the component that occupies the largest portion of the film, typically accounting for approximately 50% to 100% by mass, and even approximately 90% to 100% by mass, relative to the mass of the film. From the viewpoint of excellent adhesion to the multilayer film, the underlayer is preferably a Si (silicon)-containing inorganic layer, and more preferably a silicon oxide layer, a silicon nitride layer, or a silicon oxynitride layer. A "silicon oxide layer" is a layer containing silicon oxide as a main component, a "silicon nitride layer" is a layer containing silicon nitride as a main component, and a "silicon oxynitride layer" is a layer containing silicon oxynitride as a main component. The main components are as described above.

[0021] The method for forming the underlayer of the spectacle lens is not particularly limited. For example, a underlayer formed by sputtering a metal target and then irradiating the metal film formed by this sputtering with one or more ions selected from the group consisting of oxygen ions and nitrogen ions at least once is preferable because it has a high indentation hardness. Furthermore, spectacle lenses having underlayers formed in this manner can exhibit excellent interlayer adhesion. Forming the underlayer in this manner is also preferable in terms of suppressing cracking in the spectacle lens. In the underlayer formation process, the sputtering and ion irradiation constitute one cycle, and the process may be performed once or twice or more times. The more cycles are performed, the thicker the underlayer can be formed. Therefore, the number of cycles can be determined so that the underlayer has the desired thickness.

[0022] In the present invention and this specification, the term "metal" refers to a component selected from the group consisting of a simple metal element (pure metal) and an alloy of multiple metal elements. Metal elements include not only those classified as metal elements but also those classified as metalloid elements. For example, Si (silicon) is an example of a metalloid element, and is included in the "metal element" in the present invention and this specification.

[0023] In the present invention and this specification, a "metal target" is a sputtering target made of metal, excluding impurities inevitably mixed in during the preparation of the sputtering target and known additives optionally used to assist film formation. This also applies to "Si targets," "metal films," and the like described below. The metal content in the metal target can be, for example, in the range of 90 to 100 mass % or 95 to 100 mass %. Examples of metal targets include Si (silicon) targets, Al (aluminum) targets, and Ti (titanium) targets, with Si targets being preferred from the viewpoint of excellent adhesion to multilayer films. A silicon oxide layer can be formed by irradiating oxygen ions onto a Si film formed by sputtering with a Si target.

[0024] For example, the underlayer formation process can be carried out as follows: A metal film is formed as a sputtering film by sputtering using a metal target. Then, this metal film is irradiated with one or more ions selected from the group consisting of oxygen ions and nitrogen ions. The inventors believe that this makes it possible to obtain a film in which the metal of the metal film is oxidized and / or nitrided (i.e., a metal oxide film, a metal nitride film, or a metal oxynitride film). Furthermore, by introducing oxygen ions and / or nitrogen ions into the metal film, the transparency of the film can be increased.

[0025] Sputtering and ion irradiation for forming the underlayer can be performed in the same film formation apparatus. The configuration of such a film formation apparatus is known. For example, if a commercially available film formation apparatus equipped with a film formation mechanism using a meta-mode process is used, sputtering and ion irradiation can be performed in the same film formation apparatus. The ions to be irradiated can be oxygen ions only, nitrogen ions only, or oxygen ions and nitrogen ions. When irradiating oxygen ions and nitrogen ions, the irradiation of oxygen ions and the irradiation of nitrogen ions can be performed simultaneously, and / or one can be irradiated first and then the other. Ion irradiation can be performed using a known ion irradiation means such as an ion gun.

[0026] <Multilayer Film> The spectacle lens has a multilayer film on at least one surface of the lens substrate, and has the underlayer between the multilayer film and the lens substrate. The spectacle lens may have a multilayer film only on the object-side surface of the lens substrate, or only on the eyeball-side surface of the lens substrate, or may have a multilayer film on each of the object-side surface and the eyeball-side surface of the lens substrate. When multilayer films are located on both sides of the lens substrate, the multilayer films can be the same or different. The same applies to the underlayer.

[0027] The multilayer film may be located directly on the surface of the underlayer, or may be located indirectly on the surface of the underlayer via one or more other layers. Since the underlayer can exhibit excellent adhesion to the multilayer film, in one embodiment, the underlayer and the multilayer film can be directly laminated without any other layers interposed therebetween.

[0028] The multilayer film may have a laminated structure in which high-refractive index layers and low-refractive index layers are alternately stacked. In the present invention and this specification, the terms "high" and "low" used in relation to the high-refractive index layers and low-refractive index layers contained in the multilayer film are relative to the refractive index of the lens substrate contained in the spectacle lens. A high-refractive index layer refers to a layer with a higher refractive index than the lens substrate. A low-refractive index layer refers to a layer with a lower refractive index than the lens substrate. The multilayer film may contain three or more layers with different refractive indices. In the present invention and this specification, "refractive index" refers to the refractive index for light with a wavelength of 500 nm. The refractive index of the lens substrate of a spectacle lens is generally approximately 1.50 to 1.76, and the low-refractive index layer may be a layer with a refractive index of 1.50 or less, and the high-refractive index layer may be a layer with a refractive index of 1.76 or more. The refractive index of the high-refractive index layer may be, for example, 2.00 to 2.40 or 2.00 to 2.20. The refractive index of the low-refractive index layer may be, for example, 1.44 to 1.49. However, as described above, the terms "high" and "low" used for the high refractive index layer and the low refractive index layer are relative terms with respect to the refractive index of the lens substrate, and therefore the refractive indices of the high refractive index layer and the low refractive index layer are not limited to the above ranges.

[0029] As the high refractive index material constituting the high refractive index layer and the low refractive index material constituting the low refractive index layer, inorganic materials, organic materials, or organic-inorganic composite materials can be used, and inorganic materials are preferred from the viewpoint of film formability, etc. That is, the multilayer film is preferably an inorganic multilayer film. Specifically, as the high refractive index material constituting the high refractive index layer, zirconium oxide (e.g., ZrO ２ ), tantalum oxide (e.g., Ta ２ O ５ ), titanium oxides (e.g., TiO ２ ), aluminum oxide (e.g., Al ２ O ３ ), yttrium oxide (e.g., Y ２ O ３ ), hafnium oxide (e.g., HfO ２ ) and niobium oxide (e.g., Nb ２ O ５ On the other hand, examples of the low refractive index material constituting the low refractive index layer include silicon oxides (e.g., SiO ２ ), magnesium fluoride (e.g., MgF ２ ) and barium fluoride (e.g., BaF ２ In the above examples, the oxides and fluorides are shown in terms of stoichiometric composition for convenience, but oxides and fluorides in a state where oxygen or fluorine is deficient or excessive from the stoichiometric composition can also be used as high refractive index materials or low refractive index materials.

[0030] Preferably, the high-refractive index layer is a film primarily composed of a high-refractive index material, and the low-refractive index layer is a film primarily composed of a low-refractive index material. As described above, the "main component" refers to the component that occupies the largest proportion in the film, typically accounting for approximately 50% to 100% by mass, and even approximately 90% to 100% by mass, of the film's mass. Such films (e.g., vapor deposition films, sputtering films) can be formed by depositing a film using a film-forming material (e.g., a vacuum deposition source, a sputtering target, etc.) primarily composed of the high-refractive index material or the low-refractive index material. The same applies to the main components of the film-forming material. The film and film-forming material may contain unavoidable impurities, and may also contain other components, such as other inorganic substances or known additives that assist film formation, as long as they do not impair the function of the main component.

[0031] A known film formation method can be used to form the multilayer film. From the viewpoint of ease of film formation, film formation is preferably performed by vapor deposition. That is, each layer included in the multilayer film is preferably a vapor-deposited film. A vapor-deposited film means a film formed by vapor deposition. In the present invention and this specification, "vapor deposition" includes dry methods such as vacuum deposition, ion plating, and sputtering. In the vacuum deposition method, an ion beam assisted method in which an ion beam is irradiated simultaneously during vapor deposition may be used. As the sputtering method, a DC (Direct Current) method, an RF (Radio Frequency) method, or the like may be used.

[0032] The multilayer film can be, for example, a multilayer film in which high-refractive index layers and low-refractive index layers are alternately stacked to a total of three or more layers. The total number of high-refractive index layers and low-refractive index layers can be, for example, 11 or less. The film thicknesses of the high-refractive index layers and the low-refractive index layers can be determined depending on the layer structure. Specifically, the combination of layers included in the multilayer film and the film thickness of each layer can be determined by optical simulation using a known method based on the refractive indexes of the film-forming materials for forming the high-refractive index layers and the low-refractive index layers and the various physical properties that are desired to be imparted to the eyeglass lens by providing the multilayer film.

[0033] Examples of high-refractive index layers included in the multilayer film include layers containing zirconium oxide, layers containing niobium oxide, and layers containing tantalum oxide, and these layers are preferably layers containing these oxides as the main component. Examples of low-refractive index layers included in the multilayer film include layers containing silicon oxide, and these layers are preferably layers containing silicon oxide as the main component (silicon oxide layer). As described above, in one embodiment, the underlayer and the multilayer film can be directly laminated without any other layer. In this case, from the viewpoint of further improving the adhesion between the underlayer and the multilayer film, the bottom layer in direct contact with the underlayer in the multilayer film is preferably a layer containing an oxide of the same metal as the metal of the underlayer, and more preferably a layer containing an oxide of the same metal as the metal of the underlayer as the main component. For example, when the underlayer is a silicon oxide layer, the bottom layer in direct contact with the underlayer in the multilayer film can be a layer containing silicon oxide, and is preferably a silicon oxide layer. In the multilayer film, the high refractive index layer and the low refractive index layer may be in direct contact with each other, or the multilayer film may include at least one laminate structure in which a conductive oxide layer, which will be described later, is present between the high refractive index layer and the low refractive index layer.

[0034] The film thickness of each of the high refractive index layers and the low refractive index layers included in the multilayer film can be, for example, 1.0 to 500.0 nm, and the total thickness of the multilayer film can be, for example, 100.0 to 900.0 nm (including the thickness of the conductive oxide layer if a conductive oxide layer is included).

[0035] In addition to the high-refractive index layer and low-refractive index layer described above, the multilayer film may also include one or more layers containing a conductive oxide (also referred to as a "conductive oxide layer") at any position in the multilayer film. The conductive oxide layer may be a layer containing a conductive oxide as a main component, and may preferably be a vapor-deposited film of a conductive oxide formed by vapor deposition using a vapor deposition source containing a conductive oxide as a main component. From the viewpoint of the transparency of the eyeglass lens, the conductive oxide layer is preferably an indium tin oxide (tin-doped indium oxide; ITO) layer having a thickness of 10 nm or less, a tin oxide layer having a thickness of 10 nm or less, or a titanium oxide layer having a thickness of 10 nm or less. An indium tin oxide (ITO) layer is a layer containing ITO as a main component. This also applies to tin oxide layers and titanium oxide layers. In the present invention and this specification, the "high refractive index layer" and "low refractive index layer" included in the multilayer film do not include an indium tin oxide (ITO) layer having a thickness of 10 nm or less, a tin oxide layer having a thickness of 10 nm or less, and a titanium oxide layer having a thickness of 10 nm or less. In other words, even if one or more of these layers are included in the multilayer film, these layers are not considered to be "high refractive index layers" or "low refractive index layers." The thickness of the above-mentioned conductive oxide layer having a thickness of 10 nm or less can be, for example, 0.1 nm or more.

[0036] Furthermore, a further functional film can be formed on the multilayer film. Examples of such a functional film include various functional films such as a water-repellent or hydrophilic antifouling film and an antifogging film. Publicly known techniques can be applied to these functional films.

[0037] [Eyeglasses] A further aspect of the present invention relates to eyeglasses equipped with the eyeglass lenses according to the above-described aspect of the present invention. Details of the eyeglass lenses included in the eyeglasses are as described above. By being equipped with such eyeglass lenses, the eyeglasses can present a good appearance. There are no particular limitations on the configuration of the eyeglasses, such as the frame, and known techniques can be applied.

[0038] The present invention will be further described below with reference to examples, although the present invention is not limited to the embodiments shown in the examples.

[0039] Example 1 Formation of Underlayer (1) A lens substrate (refractive index: 1.67) was set in the deposition dome of a commercially available deposition device equipped with a deposition mechanism using a Meta mode process. －３ (2) The deposition dome was evacuated for 25.0 min until the pressure reached 0.02 Pa or less. －１ While rotating at 400° C., the substrate was heated using a heater set at a temperature of 65° C. After reaching a predetermined pressure, Ar gas (flow rate: 200 sccm) and O were sputtered from the sputtering target (Si target). ２ Gas (flow rate: 26 sccm) was introduced from the ion gun. ２ Gas (flow rate: 50 sccm) was introduced. (3) A power of 2000 W was applied to the sputtering target, and an acceleration voltage of 850 V, an acceleration current of 425 mA, a suppressor voltage of 300 V, and a bias current of 850 mA were applied to the ion gun. As the deposition dome rotated, a cycle of metal film formation → oxygen ion irradiation by the ion gun → metal film formation → oxygen ion irradiation by the ion gun → ... was repeated to deposit a film of a predetermined thickness on one surface of the lens substrate. (4) After the formation of the multilayer film described below, the lens substrate was temporarily removed and then set back in the deposition dome, and steps (1) to (3) above were carried out to deposit a film of a predetermined thickness on the other surface of the lens substrate.

[0040] <Formation of multilayer film> After the formation of the base layer, the formation of the multilayer film on both the convex and concave sides was carried out in the same film-forming apparatus without exposing the film to the atmosphere. From the base layer side toward the spectacle lens surface side, the first layer, second layer, etc. were laminated in this order using the evaporation sources shown in the bottom row of Table 1 and the top row, respectively, so that the outermost layer on the spectacle lens surface side was the layer formed by the evaporation source shown in the top row of Table 1. In Example 1, evaporation sources made of oxides shown in Table 1 were used, excluding impurities that may be unavoidably mixed in, and each layer with a thickness shown in Table 1 was formed in sequence on both the convex and concave sides. The film thickness is the physical film thickness, and is expressed in nm. SiO ２ A layer formed using a deposition source consisting of SiO ２ The refractive index of the ZrO ２ A layer formed using a deposition source consisting of ZrO ２The refractive index of the multilayer film is 2.08. The same applies to the multilayer film described later.

[0041] A water-repellent layer containing silver particles and having a thickness shown in Table 1 was formed on the surface of the outermost layer of the multilayer film on both sides of the formed eyeglass lens by the method described in paragraphs 0066 to 0067 of WO2021 / 060554.

[0042] The refractive index of each layer can be determined by the following method: A single layer film is formed on a glass substrate under the same film-forming conditions as each layer, to obtain a laminate of the glass substrate and the single layer film. The surface reflectance of the surface of the laminate on which the single layer film is formed is measured using an Olympus USPM-RU lens reflectance measuring instrument, and the refractive index is determined by optical thin film analysis of the obtained spectral reflectance.

[0043]

[0044] Example 2 A spectacle lens was produced by the method described in Example 1, except that the number of cycles in forming the underlayer was increased to form an underlayer with a thickness of 1500.0 nm.

[0045] Example 3 A spectacle lens was produced by the method described in Example 1, except that the number of cycles in forming the underlayer was increased to form an underlayer with a thickness of 2000.0 nm.

[0046] [Comparative Example 1] A spectacle lens was produced by the method described in Example 1, except that a primer layer and a hard coat layer were sequentially formed on the surface of the lens substrate as the underlayer. The primer layer and the hard coat layer were formed by applying (dip coating) a curable composition and curing it. The film thickness of the primer layer was 80.7 nm, and the film thickness of the hard coat layer was 3000.0 nm.

[0047] For each of Examples 1 to 3 and Comparative Example 1, a plurality of spectacle lenses were produced by the above-described method, and the following measurements were carried out.

[0048] [Multilayer Film Indentation Hardness, Primer Layer Indentation Hardness] The water-repellent layer on the convex side of each of the eyeglass lenses of Examples 1 to 3 and Comparative Example 1 was removed to expose the outermost layer surface of the multilayer film. The indentation hardness (multilayer film indentation hardness) of the exposed surface was measured at a load of 0.3 mN. Separately, the water-repellent layer and multilayer film were removed from the convex side of each of the eyeglass lenses of Examples 1 to 3 and Comparative Example 1 to expose the primer layer surface. For the eyeglass lens of Comparative Example 1, the primer layer surface was the hard coat layer surface. The indentation hardness (primer layer indentation hardness) of the exposed surface was measured at a load of 0.3 mN. The measurement results are shown in Table 2. Since the layer configurations on both sides of each eyeglass lens of Examples 1 to 3 and Comparative Example 1 are the same, the multilayer film indentation hardness and primer layer indentation hardness on the concave side are also the same as the values ​​shown in Table 2. This also applies to the various evaluation results that follow.

[0049]

[0050] [Scratch Resistance Evaluation 1] A steel wool scratch test was performed on the water-repellent layer surface on the convex side of the eyeglass lens under the following conditions to evaluate the scratch resistance of the eyeglass lens: Number of reciprocations = 20 (fixed) Load = 2.5 kg to 6.0 kg (test conducted in increments of 0.5 kg) Eight eyeglass lenses were prepared for each of Examples 1 to 3 and Comparative Example 1, and the eyeglass lens was replaced after each load Test with a load of 2.5 kg → Evaluation → If Passed (no scratches visible to the naked eye), a test with 3.0 kg was conducted using another eyeglass lens → Evaluation → Repeat with an increased load If Failed (scratches visible to the naked eye), the test was terminated.

[0051] The evaluation results are shown in Table 3.

[0052]

[0053] [Scratch Resistance Evaluation 2] A steel wool scratch test was performed on the surface of the water-repellent layer on the convex side of the eyeglass lens under the following conditions to evaluate the scratch resistance of the eyeglass lens: Number of reciprocations = Started from 20 times and continued until a failure was detected Load = 2.5 kg (fixed) One eyeglass lens was prepared for each of Examples 1 to 3 and Comparative Example 1, and the test was performed 20 times with a 2.5 kg load at the same location on the same eyeglass lens → Evaluation → Repeat

[0054] The eyeglass lens of Comparative Example 1 failed after two tests (thus, 40 reciprocations) under a 2.5 kg load 20 times. In contrast, the eyeglass lenses of Examples 1 to 3 passed the evaluation even after more than 200 reciprocations.

[0055] From the above evaluation results of Scratch Resistance Evaluation 1 and Scratch Resistance Evaluation 2, it can be confirmed that the eyeglass lenses of Examples 1 to 3 have excellent scratch resistance.

[0056] [Evaluation of interlayer adhesion] Interlayer adhesion was evaluated by the cross-cut method (number of squares: 10 x 10) on the convex and concave sides of each of the eyeglass lenses of Examples 1 to 3 in accordance with JIS K5600-5-6:1999. On both the convex and concave sides of each of the eyeglass lenses of Examples 1 to 3, the number of peeled squares was zero and the number of remaining squares was 100. From the above results, it can be confirmed that the eyeglass lenses of Examples 1 to 3 also have excellent interlayer adhesion.

[0057] Examples 4 to 10, Comparative Examples 2 and 3 Eyeglass lenses were produced by the method described for Example 1, except that the conditions for forming the underlayer were changed as shown in Table 4, and underlayers with thicknesses shown in Table 4 were formed. The indentation hardness was measured on the convex and concave sides of each of the eyeglass lenses of Examples 4 to 10. As a result, it was confirmed that the indentation hardness of the underlayer was greater than the indentation hardness of the multilayer film on both the convex and concave sides of each eyeglass lens.

[0058]

[0059] [Scratch Resistance Evaluation 3] A steel wool scratch test was performed on the water-repellent layer surface on the convex side of the eyeglass lens under the following conditions to evaluate the scratch resistance of the eyeglass lens. The evaluation results are shown in Table 5. Number of reciprocations = 20 times (fixed) Load = 1.0 kg (fixed) One eyeglass lens was prepared for each of Examples 4 to 10, Comparative Examples 2 and 3, and the test was performed 20 times with a 1.0 kg load on the same spot of the same eyeglass lens → judgment

[0060] [Evaluation of Interlayer Adhesion] The interlayer adhesion was evaluated by the cross-cut method (number of squares: 10 x 10) using the method described above for the convex side of each of the eyeglass lenses of Examples 4 to 10 and Comparative Examples 2 and 3. The number of remaining squares is shown in Table 5.

[0061]

[0062] From the results shown in Table 5, it can be seen that the spectacle lenses of Examples 4 to 10 are excellent in scratch resistance, whereas the spectacle lenses of Comparative Examples 2 and 3, which have thin undercoat layers, are inferior in scratch resistance.

[0063] [Comparison of Film Formation Modes] In the above examples, the underlayer was formed using a film formation mechanism based on the Meta mode process. To compare the film formation modes, the same film formation apparatus was used, but the film formation mode was changed to Reactive mode or Transition mode, and an underlayer having the film thickness shown in Table 6 was formed under the sputtering conditions shown in Table 6. Spectacle lenses were fabricated by the same method as in Example 1, except that the film formation mode was changed to Reactive mode or Transition mode, and an underlayer having the film thickness shown in Table 6 was formed under the sputtering conditions shown in Table 6. When the interlayer adhesion of the convex side of the fabricated spectacle lenses was evaluated using the above method, the number of remaining squares was 95 or less, indicating inferior interlayer adhesion compared to the above examples. Furthermore, when the appearance of the spectacle lenses thus fabricated was visually observed, cracks were confirmed. In contrast, in all of the above examples, no cracks were confirmed when the appearance of the spectacle lenses was visually observed.

[0064]

[0065] The various aspects described herein may be combined in any combination of two or more.

[0066] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0067] The present invention is useful in the field of manufacturing eyeglass lenses and eyeglasses.

Claims

1. A spectacle lens comprising a lens substrate and a multilayer film located on at least one surface of the lens substrate, further comprising an underlayer between the lens substrate and the multilayer film, wherein the underlayer has a thickness of 400.0 nm or more, and the indentation hardness measured on the surface of the underlayer at a load of 0.3 mN is greater than the indentation hardness measured on the surface of the multilayer film at a load of 0.3 mN.

2. The eyeglass lens according to claim 1, wherein the underlayer is an inorganic layer.

3. The eyeglass lens according to claim 1, wherein the multilayer film includes one or more high refractive index layers and one or more low refractive index layers, and at least one of the high refractive index layers has a refractive index of 2.00 or more and 2.40 or less.

4. The eyeglass lens according to claim 1, wherein the multilayer film includes one or more high refractive index layers and one or more low refractive index layers, and at least one of the low refractive index layers has a refractive index of 1.44 or more and 1.49 or less.

5. The eyeglass lens according to claim 1, wherein the underlayer is an inorganic layer, the multilayer film includes one or more high refractive index layers and one or more low refractive index layers, one or more of the high refractive index layers having a refractive index of 2.00 or more and 2.40 or less, and one or more of the low refractive index layers having a refractive index of 1.44 or more and 1.49 or less.

6. A method for manufacturing an eyeglass lens according to any one of claims 1 to 5, comprising forming the underlayer by performing sputtering using a metal target and irradiating the metal film formed by said sputtering with one or more types of ions selected from the group consisting of oxygen ions and nitrogen ions, at least once.

7. The method for manufacturing eyeglass lenses according to claim 6, wherein the metal target is a Si target.

8. The method for manufacturing eyeglass lenses according to claim 6, wherein the ion irradiation is carried out by an ion gun.

9. Eyeglasses equipped with the eyeglass lens according to any one of claims 1 to 5.

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