Eyeglass lenses

Abstract

This spectacle lens comprises: a base material layer; and a coat film layer laid on for coating at least one surface of the base material layer. A total average transmittance of the base material layer and the coat film layer is 60% or higher in a wavelength region of not less than 360 nm but less than 380 nm.

Description

[Technical field]

[0001] The present invention relates to a lens for spectacles. [Background technology]

[0002] Existing eyeglass lenses use materials that block ultraviolet rays (see, for example, Patent Document 1), and most lenses do not transmit ultraviolet rays (see, for example, Patent Document 2). On the other hand, it has been pointed out that sunlight has a positive effect on the physical and mental development of children in particular, and that if children are not exposed to sufficient sunlight, the risk of myopia progression increases (see, for example, Non-Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-209120 A [Patent Document 2] International Publication No. 2019 / 188447 [Non-patent literature]

[0004] [Non-Patent Document 1] Japan Ophthalmological Society and five other societies, “Cautionary opinion regarding the use of blue light blocking glasses in children,” April 14, 2021, [Retrieved January 27, 2022], Internet<https: / / www.gankaikai.or.jp / info / 20210414_bluelight.pdf> Summary of the Invention [Problem to be solved by the invention]

[0005] Here, for a user who wears glasses, in order to allow natural light, including ultraviolet rays, to reach their eyes, the user must remove the glasses, and the effect of vision correction provided by the glasses cannot be obtained.

[0006] In order to solve the above problems, it is conceivable to form the substrate of the eyeglass lens using a compound that transmits ultraviolet light, but in order to satisfy the durability requirements of eyeglass lenses, a coating film is generally applied to the substrate. In eyeglass lenses of such a general configuration, there is a new demand for transmitting ultraviolet light that was previously blocked, taking into consideration the overall characteristics of the substrate and the coating film, in order to allow as much natural light as possible to reach the eye.

[0007] Therefore, an object of the present invention is to provide a lens for glasses that transmits as much ultraviolet light as possible and realizes a state as close as possible to when the naked eye is exposed to natural light. [Means for solving the problem]

[0008] The eyeglass lens in one aspect of the present invention comprises a substrate layer and a coating film layer coated on at least one surface of the substrate layer, and the substrate layer and the coating film layer have a total average transmittance of 60% or more in a wavelength region of 360 nm or more and less than 380 nm. Effect of the Invention

[0009] According to the present invention, it is possible to provide a lens for glasses that transmits ultraviolet light as much as possible. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing the light transmittance of each eyeglass lens according to the prior art. [Diagram 2] FIG. 4 is a diagram showing an example of the light transmittance of a substrate A according to the first embodiment. [Diagram 3] FIG. 4 is a diagram showing an example of light transmittance of a substrate B according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing an example of the light transmittance of a substrate C according to the first embodiment. [Diagram 5] FIG. 11 is a diagram showing an example of light transmittance of a substrate candidate according to the second embodiment. [Figure 6]FIG. 11 is a diagram showing an example of light transmittance when both sides of each of the resins 1 to 10 according to the second embodiment are coated with an ultraviolet-visible AR coating film layer that prevents reflection of ultraviolet light and visible light. [Figure 7] FIG. 13 is a table comparing the average transmittance when each coating film layer is applied to resins 1, 3, and 6 according to the second embodiment. [Figure 8] FIG. 1 is a comparison diagram of the transmittance of resins 1, 3, and 6 with that of an existing lens. [Figure 9] FIG. 1 is a table comparing the transmittance in each region of Resins 1, 3, and 6 with that of an existing lens. [Figure 10] FIG. 1 shows Table A comparing the transmittance in each region of Resins 1, 3 and 6. [Figure 11] FIG. 1 shows Table B comparing the transmittance in each region of Resins 1, 3 and 6. [Figure 12] FIG. 13 is a diagram showing the reflectance of each anti-reflection film with respect to resin 6. [Figure 13] FIG. 13 is a diagram showing the transmittance of resin 3 due to differences in the AR coating film layers on each surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiments described below are merely examples, and there is no intention to exclude the application of various modifications and techniques not specified below. In other words, the present invention can be implemented with various modifications within the scope of the gist of the present invention. In addition, in the following description of the drawings, the same or similar parts are represented by the same or similar reference numerals. The drawings are schematic and do not necessarily correspond to actual dimensions, ratios, etc. The drawings may also include parts with different dimensional relationships and ratios.

[0012] [First embodiment] <Existing eyeglass lenses> Fig. 1 is a diagram showing the light transmittance of each spectacle lens according to the conventional technology (special eyeglass lenses according to the conventional technology are also collectively referred to as "existing lenses"). In the example shown in Fig. 1, the light transmittance is measured using the following four lenses. Lens A: A lens (refractive index 1.50) made of CR-39 (registered trademark) (allyl diglycol carbonate) manufactured by PPG Industries, Inc. Lens B: Thiourethane lens (refractive index 1.60) Lens C: Thiourethane lens (refractive index 1.67) Lens D: Thiourethane lens (refractive index 1.74)

[0013] Lenses A to D each have a hard coat and an anti-reflective coat formed on both sides of the substrate. As shown in Fig. 1, lenses A to D each cut off wavelengths shorter than 380 nm. This shows that lenses A to D each have at least one of the following: the substrate contains an ultraviolet absorbing agent, the hard coat contains an ultraviolet absorbing agent, and the anti-reflective coat contains an ultraviolet absorbing agent.

[0014] Therefore, in many existing lenses, not just those for vision correction, the wavelengths absorbed by the lens vary slightly depending on the lens manufacturer and material, but all lenses cut out wavelengths shorter than 380 nm.

[0015] In light of the effects of ultraviolet light on the eyes that have become evident in recent years, the inventors came up with the idea of ​​transmitting ultraviolet light through eyeglass lenses. However, as shown in Figure 1, most existing eyeglass lenses block ultraviolet light, and no lenses that meet the inventors' desire exist.

[0016] <Substrate of the eyeglass lens of the present invention> First, the substrate of the eyeglass lens according to the first embodiment of the present invention will be described. The eyeglass lens according to the first embodiment does not use a substrate mainly made of a material that absorbs ultraviolet rays. For example, aromatic compounds and aliphatic compounds having a conjugated structure are known as materials that absorb ultraviolet rays, so substrates mainly made of these compounds are not used for eyeglass lenses according to the first embodiment.

[0017] The eyeglass lens according to the first embodiment includes a base layer mainly made of a first compound other than a compound that absorbs a predetermined percentage or more of ultraviolet light. The material that absorbs a predetermined percentage or more of ultraviolet light includes, for example, the aromatic compound described above. The base layer may also contain an aromatic compound to the extent that it does not interfere with the purpose of the first embodiment.

[0018] In this way, since the base layer is made of the first compound other than the compound that absorbs a certain percentage or more of ultraviolet light, it is possible to prevent the transmission of ultraviolet light from being significantly hindered by at least the base layer of the eyeglass lens. Therefore, ultraviolet light passes through the eyeglass lens, and light similar to natural light including ultraviolet light reaches the eye.

[0019] In the first embodiment, the ultraviolet light has a wavelength in the wavelength range of, for example, 280 to 400 nm. Of these, 320 to 400 nm is called UVA (first wavelength range), and 280 to 320 nm is called UVB (second wavelength range). The boundary between UVA and UVB may be 315 nm, and the upper limit of UVA may be 380 nm. The eyeglass lens in the first embodiment is configured to transmit wavelengths of 280 to 400 nm, rather than cutting them.

[0020] The first compound used to form the base layer is, for example, a compound other than an aromatic compound, and includes at least one of an aliphatic polycarbonate, an aliphatic olefin polymer, an aliphatic acrylic resin, and an aliphatic nylon resin.

[0021] Substrates made of aliphatic polycarbonate include, for example, at least one of commercially available CR-39 (registered trademark) manufactured by PPG Corporation and DURABIO (registered trademark) manufactured by Mitsubishi Chemical Corporation. CR-39 (registered trademark) is a linear aliphatic polycarbonate without aromatic rings, and therefore has a low ultraviolet absorption function. DURABIO (registered trademark) is a partially biomaterial polycarbonate that uses isosorbide, which is a biomaterial. This compound is considered to have a low ultraviolet absorption function because the diol copolymerized with isosorbide is also alicyclic and does not have an aromatic ring.

[0022] The aliphatic olefin polymer includes, for example, at least one of a cycloolefin polymer (alicyclic olefin polymer) and an aliphatic olefin polymer having no cyclic structure, etc. The substrate formed using the cycloolefin polymer includes, for example, any of commercially available APEL (registered trademark) manufactured by Mitsui Chemicals, Inc. (refractive index 1.544, Abbe number 56), ZEONEX (registered trademark) manufactured by Zeon Corporation (refractive index 1.509 to 1.535), and ARTON (registered trademark) manufactured by JSR Corporation (refractive index 1.513 to 1.516, Abbe number 56 or 57).

[0023] The substrate formed of an aliphatic olefin polymer having no cyclic structure includes, for example, TPX (registered trademark) (chemical compound name: polymethyltempene) (refractive index: 1.46) commercially available from Mitsui Chemicals.

[0024] An example of a substrate made of aliphatic acrylic resin that can be used is the "UV-transmitting PMMA lens" (refractive index: approx. 1.49, Abbe number: 55) manufactured by Nippon Tokushu Kogaku Jushi Co., Ltd. PMMA is an abbreviation for polymethyl methacrylate. UV-transmitting PMMA is an acrylic resin that transmits UV rays.

[0025] 2 to 4, the light transmittance of the substrates A to C will be described. First, as described above, the spectacle lens in the first embodiment transmits as much light as possible in the wavelength region of 280 to 400 nm.

[0026] FIG. 2 is a diagram showing an example of the light transmittance of the substrate A according to the first embodiment. The substrate A is formed from a resin using a cycloolefin polymer, and has a refractive index of 1.544. In the wavelength region of 300 to 400 nm, the substrate A transmits wavelengths in the ultraviolet region more than the existing spectacle lens shown in FIG. 1. In the example shown in FIG. 2, the substrate A has a transmittance of about 15% in the vicinity of a wavelength of 300 nm. Also, in the first wavelength region (320 to 400 nm), the substrate A has a transmittance of about 60% on average.

[0027] FIG. 3 is a diagram showing an example of the light transmittance of the substrate B according to the first embodiment. The substrate B is formed from a resin using a cycloolefin polymer, and has a refractive index of 1.51. The substrate B transmits wavelengths in the ultraviolet region in the wavelength region of 280 to 400 nm, compared to the existing eyeglass lens shown in FIG. 1. In the example shown in FIG. 3, the substrate B has a transmittance that rises sharply from around a wavelength of 280 nm, and has an average transmittance of about 35% in the second wavelength region (280 to 320 nm). Also, in the first wavelength region (320 to 400 nm), it has an average transmittance of about 85%.

[0028] FIG. 4 is a diagram showing an example of light transmittance of the substrate C according to the first embodiment. The substrate C is formed from a resin using PMMA that transmits ultraviolet light, and has a refractive index of 1.49 and an Abbe number of 55. In the wavelength range of 280 to 400 nm, the substrate C transmits wavelengths in the ultraviolet range more than the existing eyeglass lens shown in FIG. 1. In the example shown in FIG. 4, the substrate C has an average transmittance of about 55% in the second wavelength range (280 to 320 nm). Also, in the first wavelength range (320 to 400 nm), it has an average transmittance of about 90%.

[0029] 2 to 4, since the substrate C transmits wavelengths in the ultraviolet region of 280 to 400 nm well, the substrate C can be suitably used as the substrate layer of the eyeglass lens. Note that the substrates A and B also transmit wavelengths in the ultraviolet region better than the substrate layers of existing eyeglass lenses, and therefore can be used as the substrate of the eyeglass lens.

[0030] <Coating> The eyeglass lens may have a hard coat film layer (which may be written as "hard coat", "hard coat film", or "hard coat layer") formed on at least one surface of the substrate layer. The eyeglass lens in the first embodiment may have a hard coat film layer formed of a material that does not contain an ultraviolet absorbent, coated on at least one surface of the substrate layer. The hard coat film layer is formed, for example, by uniformly applying a hard coat liquid to the surface of the substrate layer, and it is preferable that a resin that does not contain an aromatic compound is used.

[0031] For example, the hard coat film layer of the eyeglass lens may preferably be an organosiloxane-based resin containing inorganic oxide fine particles. The organosiloxane-based resin is preferably obtained by hydrolyzing and condensing an alkoxysilane. Specific examples of the organosiloxane-based resin include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, methyltrimethoxysilane, ethyl silicate, or a combination thereof. The hydrolysis condensate of the alkoxysilane is produced by hydrolyzing the alkoxysilane compound or a combination thereof with an acidic aqueous solution such as hydrochloric acid.

[0032] In addition, the material of the inorganic oxide microparticles includes, for example, sols of zinc oxide, silicon dioxide (silica microparticles), aluminum oxide, titanium oxide (titania microparticles), zirconium oxide (zirconia microparticles), tin oxide, beryllium oxide, antimony oxide, tungsten oxide, and cerium oxide, either alone or in combination of two or more of them.

[0033] From the viewpoint of ensuring the transparency of the hard coat film layer, the diameter of the inorganic oxide fine particles is preferably 1 nm to 100 nm, more preferably 1 nm to 50 nm. Also, from the viewpoint of ensuring an appropriate degree of hardness and toughness in the hard coat film layer, the blending amount (concentration) of the inorganic oxide fine particles is preferably 40 wt % to 60 wt % of the total components of the hard coat film layer.

[0034] In addition, at least one of acetylacetone metal salt and ethylenediaminetetraacetic acid metal salt is added to the hard coat liquid as a curing catalyst, and further, a surfactant, a colorant, a solvent, etc. are added as necessary for ensuring adhesion to the substrate, facilitating formation, imparting a desired (semi)transparent color, etc.

[0035] The inorganic oxide (metal oxide) in the inorganic oxide microparticles is selected to have as little absorption as possible in the visible range. This is from the viewpoint of ensuring high transmittance over the entire visible range and ensuring a state in which the difference in color seen with the naked eye and the color seen when wearing the lens is extremely small. From this viewpoint, the inorganic oxide is preferably an oxide of one or more metals other than Ti (titanium) and Ce (cerium). Since Ti (titanium) oxide and Ce (cerium) oxide have absorption in the visible range (especially on the short wavelength side), they are excluded from the preferable metal oxides.

[0036] Examples of suitable metal oxides include oxides of Sb (antimony), Sn (tin), Si (silicon), Al (aluminum), Ta (tantalum), La (lanthanum), Fe (iron), Zn (zinc), W (tungsten), Zr (zirconium), and In (indium), or combinations thereof.

[0037] The physical thickness of the hard coat film layer is preferably 0.5 μm (micrometers) or more and 4.0 μm or less. The lower limit of this film thickness range is determined because it is difficult to obtain sufficient hardness if the film thickness is thinner than this. On the other hand, the upper limit is determined because if the film thickness is made thicker than this, the possibility of problems with physical properties such as cracks and brittleness increases dramatically, and the influence of absorption (reduction in transmittance) in the visible range by inorganic oxide fine particles increases. In addition to these thermosetting coating agents, the hard coat agent used in the hard coat film layer may be a known photocuring coating agent.

[0038] The eyeglass lens in the first embodiment may also include an anti-reflection coating layer (which may be written as "anti-reflection coating" or "anti-reflection layer") formed of a material that does not contain an ultraviolet absorbing agent and that is coated on at least one surface of the substrate layer. The anti-reflection coating layer may be formed on the substrate layer, but may preferably be formed on the hard coat film layer. The anti-reflection coating layer is preferably formed of an optical multilayer film, and may use a component that does not contain an aromatic compound.

[0039] From the viewpoint of ensuring an anti-reflection function, the optical multilayer film is preferably formed so as to have a flat and high transmittance distribution over the entire range of ultraviolet light and visible light.

[0040] The optical multilayer film is formed by alternately laminating low-refractive index layers and high-refractive index layers, and preferably has an odd number of layers overall (a total of 5 layers, 7 layers, etc.). More preferably, assuming that the layer closest to the substrate (the layer closest to the substrate) is the first layer, the odd-numbered layers are low-refractive index layers and the even-numbered layers are high-refractive index layers. The low-refractive index layers and high-refractive index layers are formed by vacuum deposition, ion-assisted deposition, ion plating, sputtering, etc.

[0041] According to the experiment conducted by the inventors of the present application, there is data showing that forming an anti-reflection film layer on a substrate layer or a hard coat film layer increases the transmittance of visible light by about 5%. Therefore, by providing an anti-reflection film layer, it is possible to improve the transmittance even in the ultraviolet wavelength region.

[0042] <Eyeglass lenses> The eyeglass lens according to the first embodiment includes the above-mentioned substrate layer and coating film layer. For example, the substrate is formed as the substrate layer of the eyeglass lens using the compounds shown in Figs. 2 to 4, and the hard coating film layer and / or the anti-reflection film layer as the above-mentioned coating film layer is formed on at least one surface of the substrate layer. In addition, the eyeglass lens according to the first embodiment can transmit ultraviolet light, and the average transmittance of both the substrate and the coating film is at least 10% in the ultraviolet light region. As a result, in the existing eyeglass lenses, as shown in Fig. 1, the average transmittance in the ultraviolet light region is less than 10%, but in the eyeglass lens according to the first embodiment, the average transmittance in the ultraviolet light region is 10% or more due to the total transmittance characteristics of the substrate layer and the coating film layer, and ultraviolet light can be transmitted more than the existing eyeglass lenses, allowing more natural light to reach the eyes. In addition, the eyeglass lens according to the first embodiment can also be applied to prescription eyeglass lenses, allowing the user to receive light close to natural light while correcting their eyesight.

[0043] In addition, the eyeglass lens according to the first embodiment is preferably such that the total average transmittance (or transmittance) of the substrate layer and the coating film layer is 5% or more in UVB (second wavelength region) of 280 nm or more and less than 320 nm, and the total average transmittance (or transmittance) of the substrate layer and the coating film layer is 15% or more in UVA (first wavelength region) of 320 nm or more and 400 nm or less. In particular, by transmitting the first wavelength region including a part of blue light of 380 nm to 495 nm and its surrounding wavelength region more than the second wavelength region of shorter wavelength, more natural sunlight reaches the eyes compared to existing eyeglass lenses with ultraviolet ray cutting function, and therefore, a favorable effect on the mental and physical development of children and a reduction in the risk of myopia progression can be expected. In addition, the fact that ultraviolet rays in the first wavelength region are transmitted more can be said for any eyeglass lens according to the first embodiment.

[0044] More preferably, the eyeglass lens according to the first embodiment has a total average transmittance (or transmittance) of the substrate layer and the coating film layer of 10% or more in UVB (second wavelength region) of 280 nm or more and less than 320 nm, and a total average transmittance (or transmittance) of the substrate layer and the coating film layer of 55% or more in UVA (first wavelength region) of 320 nm or more and 400 nm or less. Here, even with only the substrate made of the compound shown in Figures 2 to 3, the average transmittance of the second wavelength region is about 15% to 35%, and the average transmittance of the first wavelength region is about 60% to 85%. Therefore, even if a predetermined coating film layer is formed on the substrate shown in Figures 2 to 3, it is possible to ensure that at least the average transmittance (or transmittance) of the second wavelength region is about 10% or more, and the average transmittance (or transmittance) of the first wavelength region is about 55% or more.

[0045] In addition, the eyeglass lens according to the first embodiment is more preferably such that the total average transmittance (or transmittance) of the substrate layer and the coating film layer is 50% or more in UVB (second wavelength region) from 280 nm to less than 320 nm, and the total average transmittance (or transmittance) of the substrate layer and the coating film layer is 85% or more in UVA (first wavelength region) from 320 nm to 400 nm. Here, even if the substrate is made of the compound shown in FIG. 4 alone, the average transmittance of the second wavelength region is about 55%, and the average transmittance of the first wavelength region is about 90%. Therefore, even if the substrate is made of the compound shown in FIG. 4 as the substrate layer and a predetermined coating film layer is formed, it is possible to ensure that at least the average transmittance (or transmittance) of the second wavelength region is about 50% or more, and the average transmittance (or transmittance) of the first wavelength region is about 85% or more.

[0046] The eyeglass lens may be configured with an upper limit on the average transmittance in the ultraviolet region. For example, the eyeglass lens according to the first embodiment may have an upper limit of 65% on the total average transmittance of the substrate layer and the coating film layer in the ultraviolet region of 280 nm to 400 nm.

[0047] Moreover, the upper limit of the transmittance may be set for each of the first wavelength region and the second wavelength region. For example, the upper limit of the total transmittance of the substrate layer and the coating film layer in the first wavelength region may be 80%, and the upper limit of the total transmittance of the substrate layer and the coating film layer in the second wavelength region may be 50%. In order to set an upper limit for the transmittance in the ultraviolet region, a predetermined amount of ultraviolet absorber may be mixed into the main material of the substrate or the coating film. In this way, the eyeglass lens according to the first embodiment can transmit an appropriate wavelength region or an appropriate amount of ultraviolet light, taking into account the advantages and disadvantages of exposing the eyes to ultraviolet light.

[0048] In addition, the refractive index of the base layer in the first embodiment is preferably higher than the refractive index of glass in the short wavelength region. In addition, the eyeglass lens in the first embodiment is subjected to various treatments to ensure the generally required performance for lens resistance such as ultraviolet degradation and wear. In this case, it is preferable that the treatment is not performed using a material that absorbs ultraviolet rays.

[0049] [Second embodiment] Next, in the second embodiment, a spectacle lens that transmits ultraviolet light as much as possible will be described, similarly to the first embodiment. Here, the inventors have investigated the transmittance in the ultraviolet region and the visible light region for various resins that are candidates for the substrate layer of the spectacle lens of the present disclosure.

[0050] 5 is a diagram showing an example of light transmittance of candidate base materials according to the second embodiment. The resins that are candidate base materials shown in FIG. Resin 1: ACRYPET (registered trademark) VH000 Resin 2: Acrylite (registered trademark) L000 Resin 3: ZEONEX (registered trademark) K22R Resin 4: ZEONEX (registered trademark) K26R Resin 5: TPX® RT18 Resin 6: ARTON® F3500 Resin 7: APEL® 5014XH Resin 8: CR-39 (registered trademark) Resin 9: MR-8 (registered trademark) Resin 10: MR-10 (registered trademark) Resins 1 to 6 and 8 to 10 are all test pieces having a thickness of 2 mm, and only resin 7 is a test piece having a thickness of 3 mm.

[0051] The resins shown in Fig. 5 have a steep increase in transmittance in a lower wavelength region compared to the existing eyeglass lenses shown in Fig. 1. For example, the transmittance of existing eyeglass lenses rises steeply from around 380 nm, but the resins shown in Fig. 5 have a steep increase in transmittance in the wavelength region of 330 nm or less.

[0052] From this, it can be seen that each resin shown in FIG. 5 transmits wavelengths in the ultraviolet region (280-400 nm or 280-380 nm). In particular, considering the tendency of the transmittance curve, in order to transmit as much ultraviolet light as possible, it is important that the transmittance in the wavelength region of 360-380 nm is high compared to existing lenses. For example, in all of resins 1-10, the average transmittance in the wavelength region of 360-380 nm exceeds 80% for the resin alone, and the transmittance itself also exceeds 80% in the same region. Furthermore, in resins 1-4 that are preferred in the technology disclosed herein, the average transmittance in the wavelength region of 360-380 nm exceeds 90%.

[0053] The reason why the transmittance in the wavelength region of 360 to 380 nm is required to be high is that if the transmittance in this region is high (for example, the threshold is 60%, 80% or more), even if the transmittance tends to decrease in the wavelength region of 360 nm or less, the transmittance will start to decrease from a high transmittance in the wavelength region of 360 to 380 nm, so that the transmittance can be maintained at a constant level on average in the wavelength region of 280 to 360 nm. For example, even Resin 6, whose transmittance decreases at the longest wavelength (near 360 nm), has an average transmittance of 25 to 30% in the wavelength region of 280 to 360 nm.

[0054] 5, resin 1 has a transmittance of 60% or more at 280 nm, and transmits light in the ultraviolet region well. The average transmittance of each resin in the UVA region (315 to 400 nm) is as follows: Resin 1: 90.7%, Resin 2: 91.2%, Resin 3: 83.5%, Resin 4: 87.4%, Resin 5: 83.4%, Resin 6: 64.7%, Resin 7: 68.7%, Resin 8: 85.2%, Resin 9: 82.7%, Resin 10: 76.3% As described above, in the UVA region, resins 1 to 5 and 8 to 10 have an average transmittance of 75% or more, resins 1 to 2, 4 and 8 which are preferred for the present disclosed technology have an average transmittance of 85% or more, and resins 1 to 2 which are particularly preferred for the present disclosed technology have an average transmittance of 90% or more.

[0055] Fig. 6 is a diagram showing an example of light transmittance when both sides of resins 1 to 10 shown in Fig. 5 are coated with an ultraviolet-visible AR (Anti Reflection) coating film layer that prevents reflection of ultraviolet light and visible light. Comparing the light transmittance shown in Fig. 6 with that shown in Fig. 5, first, in the ultraviolet region (380 nm or less), each resin formed with an ultraviolet-visible AR coating film layer has improved transmittance. For example, in the case of resin 4, the transmittance of only the resin is about 75% in the vicinity of 315 nm, whereas the transmittance of the resin with the ultraviolet-visible AR coating film layer is about 80%, which is an improvement of about 5% in transmittance.

[0056] In the visible light region (lower limit 380-400 nm, upper limit 760-780 nm), the average transmittance of each resin with the ultraviolet-visible AR coating film layer exceeds about 95%, but the average transmittance of the resin alone is about 85-90%. As a result, by forming the ultraviolet-visible AR coating film layer on the substrate, it is possible to transmit more of the visible light region as well as more of the ultraviolet region.

[0057] Fig. 7 is a table comparing the average transmittance when each coating film layer is applied to resins 1, 3, and 6 according to the second embodiment. In the example shown in Fig. 7, the visible light AR coated product represents a resin coated on both sides (one side and the side opposite to the one side) with a film layer that prevents reflection of visible light, and the ultraviolet and visible light AR coated product represents a resin coated on both sides with a film layer that prevents reflection of ultraviolet light and visible light.

[0058] Fig. 7A is a diagram showing a table of the average transmittance of each resin in the UVA and UVB regions. In the example shown in Fig. 7A, even with only the substrate, the average transmittance of resin 1 and resin 3 is 36.2% or more in the UVA and UVB regions. In particular, in the UVA region, resin 1 and resin 3 have an average transmittance of 80% or more even with only the substrate, and can be a suitable lens in the technology disclosed herein.

[0059] Furthermore, even with just the base material of Resin 6, the average transmittance in the UVB region is just under 10%, but the UVA region transmits 57.4% of light, providing sufficient transmittance in the ultraviolet region compared to existing lenses.

[0060] When a commonly used visible light AR coating film layer is coated on both sides, the transmittance of each resin decreases by several percent to several tens percent in both the UVA and UVB regions. This is thought to be because the visible light AR coating film layer prevents the reflection of visible light, but does not prevent the reflection of wavelengths in the ultraviolet region, so it reflects wavelengths in the ultraviolet region, reducing the amount of ultraviolet light that passes through the coated resin (substrate).

[0061] When the ultraviolet-visible AR coating film layer that prevents reflection of ultraviolet light and visible light is coated on both sides due to the technology disclosed herein, the transmittance of each resin increases by several percent in both the UVA and UVB regions. For example, the transmittance of each of resins 1 to 6 increases by 3% or more in the UVA region, and it is possible to provide a lens that transmits the ultraviolet region better than the case of the substrate alone and is close to the naked eye. In particular, resin 6 has a transmittance of more than 60% in the UVA region by forming an ultraviolet-visible AR coating film layer.

[0062] Fig. 7B is a table showing the average transmittance in the ultraviolet region, 280 to 380 nm (region 1) and 280 to 400 nm (region 2). As shown in Fig. 7B, the average transmittance of the substrate made of resin 1 alone exceeds 86% in both regions, making it possible to produce a lens that transmits ultraviolet light well. The substrate made of resin 3 alone also has an average transmittance of 65%, and the substrate made of resin 6 alone also has an average transmittance of more than 40%.

[0063] Comparing the average transmittance in Region 1 and Region 2, Region 2 has a higher average transmittance by a few percent. This shows that for each resin, the transmittance increases as the wavelength goes from short to long, and the transmittance in the 380-400 nm range increases the average transmittance by a few percent.

[0064] When the ultraviolet-visible light AR coating film layer of Resin 1 is coated on both sides, the average transmittance exceeds 90% in region 2 and is approximately 89% in region 1, indicating that it is possible to provide lenses that are close to those seen by the naked eye. In addition, when the ultraviolet-visible light AR coating film layer of Resin 3 and 6 is coated on both sides, the transmittance exceeds 50% in region 2 and exceeds 42% in region 1 compared to existing lenses, indicating that the ultraviolet region is sufficiently transmitted.

[0065] From the above, it was confirmed that the average transmittance increases by coating not only the substrate but also the ultraviolet-visible AR coating film layer (FIGS. 5 to 7). Therefore, it is possible to increase the average transmittance by coating at least one surface of the substrate layer of each of the substrate candidates for each resin shown in FIG. 5 with an ultraviolet-visible AR coating film layer. Therefore, when at least one surface of each of the resins 1 to 10 shown in FIG. 5 is coated with an ultraviolet-visible AR coating film layer, it is possible to increase the average transmittance of 360 to 380 nm to 80% or more.

[0066] Next, the inventors selected three resins, Resins 1, 3, and 6, as candidate materials for the eyeglass lenses of the present disclosure and conducted various experiments, and the results of each experiment will be described.

[0067] FIG. 8 is a comparison diagram of the transmittance of resins 1, 3, and 6 with existing lenses. In the example shown in FIG. 8, existing lens 1 is Hilux (registered trademark) Hard Coat S0.00 manufactured by HOYA Corporation, and existing lens 2 is Hilux (registered trademark) VP_S0.00. In the example shown in FIG. 8, each resin is a test piece of a 2 mm thick base material layer made of the respective resin, on both sides of which an ultraviolet-visible light AR coating film layer is formed. As in FIG. 8, each resin in the following FIGS. 9 to 11 is a 2 mm thick base material layer that has been subjected to a predetermined treatment.

[0068] As shown in Fig. 8, Existing Lenses 1 and 2 are eyeglass lenses that have a relatively higher transmittance in the ultraviolet region than the existing lens shown in Fig. 1, but the transmittance still drops sharply from around 400 nm to the low wavelength region. On the other hand, Resins 1, 3, and 6 have an average transmittance of about 90% or more in the 360-380 nm region, and Resins 1 and 3 have a transmittance of over 90% in the 360-380 nm region.

[0069] According to the graph in FIG. 8, Resins 1, 3, and 6 have higher transmittance than Existing Lenses 1 and 2 in the ultraviolet region (280 to 400 nm or 280 to 380 nm), and therefore Resins 1, 3, and 6 transmit more ultraviolet light.

[0070] FIG. 9 is a table comparing the transmittance in each region of resins 1, 3, and 6 with existing lenses. The transmittance is also compared when a radical scavenger is added to the base layer of each resin shown in FIG. 9. The radical scavenger is Adeka STAB (registered trademark) (LA-63P, LA-52, or LA-57) from ADEKA Corporation, and 0.2 wt% is added to the base layer of each resin. The radical scavenger prevents lens deterioration, making it possible to improve the durability of the lens.

[0071] In the results shown in Fig. 9(A), in the case of Resin 1 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the 360-380 nm region is 95.1%, and the average transmittance in the 360-400 nm region is 95.6%. In the case of Resin 1 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-63P), the average transmittance in the 360-380 nm region is 91.5%, and the average transmittance in the 360-400 nm region is 92.7%. In Resin 1, even when a radical scavenger is added to the base layer, the average transmittance in each region exceeds 90%.

[0072] In the results shown in Fig. 9(B), in the case of Resin 3 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the 360-380 nm region is 95.0%, and the average transmittance in the 360-400 nm region is 95.5%. In the case of Resin 3 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-52 or LA-57), the average transmittance in the 360-380 nm region is about 88-90%, and the average transmittance in the 360-400 nm region is about 90-91%. In Resin 3, even when a radical scavenger is added to the base layer, the average transmittance in each region is about 90%.

[0073] 9(C), in the case of Resin 6 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the 360-380 nm region is 89.8%, and the average transmittance in the 360-400 nm region is 91.5%. In the case of Resin 6 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-52), the average transmittance in the 360-380 nm region is 81.9%, and the average transmittance in the 360-400 nm region is 84.8%.

[0074] In addition, in resin 6, 0.001 wt% of an ultraviolet absorber (ADEKA STAB (registered trademark) LA-46 of ADEKA Corporation), which is generally added for the purpose of preventing deterioration of lenses, was further added as a comparative example. Even so, the average transmittance in the region of 360 to 380 nm was 77.8%, and the average transmittance in the region of 360 to 400 nm was 82.6%. The average transmittance exceeds 75% in both regions, and it is found that ultraviolet rays are transmitted well. Although the average transmittance in the regions of 360 to 380 nm and 360 to 400 nm is slightly lower when an ultraviolet absorber is additionally added compared to the case of only a radical scavenger, it can be inferred from the degree of the decrease that the average transmittance in the corresponding regions can be maintained at a high level even when only an ultraviolet absorber with an appropriately adjusted amount added is added to the base layer instead of a radical scavenger.

[0075] 9(A) to (C), the ultraviolet-visible AR coating film layer formed on the lens has a higher transmittance in the ultraviolet region than the general visible AR coating film layer formed on the lens, which confirmed the effectiveness of the ultraviolet-visible AR coating film layer.

[0076] In the results shown in FIG. 9(D), the existing lens 1 has an average transmittance of 46.0% in the 360-380 nm region, and an average transmittance of 64.5% in the 360-400 nm region. The existing lens 2 has an average transmittance of 39.6% in the 360-380 nm region, and an average transmittance of 60.4% in the 360-400 nm region. The existing lenses 1 and 2 cannot have an average transmittance of more than 60% in the 360-380 nm region. This makes it possible to form a significant difference from the existing lenses by forming a spectacle lens in which the total average transmittance of the substrate layer and the coating film layer is 60% or more in the wavelength region of 360 nm or more and less than 380 nm.

[0077] Fig. 10 is a diagram showing Table A which compares the transmittance in each region of Resins 1, 3 and 6. The table shown in Fig. 10 compares the transmittance in the UVA (315 to 380 nm) region and the UVB (280 to 315 nm) region.

[0078] In the results shown in Fig. 10(A), in the case of Resin 1 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the UVA region is 93.8% and the average transmittance in the UVB region is 79.8%. In the case of Resin 1 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-63P), the average transmittance in the UVA region is 89.0% and the average transmittance in the UVB region is 60.5%.

[0079] In the results shown in FIG. 10(B), in the case of resin 3, with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the UVA region is 85.0%, and the average transmittance in the UVB region is 37.3%. In the case of resin 3 with an ultraviolet-visible light AR coating film layer and a radical scavenger (LA-52), the average transmittance in the UVA region is 67.1%, and the average transmittance in the UVB region is 14.2%. In the case of resin 3 with an ultraviolet-visible light AR coating film layer and a radical scavenger (LA-57), the average transmittance in the UVA region is 60.5%, and the average transmittance in the UVB region is 7.8%. In the case of resin 3, as a radical scavenger, LA-52 has a higher average transmittance in each region than LA-57.

[0080] In the results shown in Fig. 10(C), in the case of Resin 6 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in the UVA region is 60.5% and the average transmittance in the UVB region is 9.2%. In the case of Resin 6 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-52), the average transmittance in the UVA region is 49.2% and the average transmittance in the UVB region is 3.2%.

[0081] In addition, 0.001 wt% of ultraviolet absorber (LA-46) was further added to resin 6 as a comparative example, as in FIG. 9(C). In this case, in resin 6 with an ultraviolet-visible AR coating film layer, the average transmittance in the UVA region was 43.8%, and the average transmittance in the UVB region was 2.3%. Similarly, even if only an ultraviolet absorber with an appropriately adjusted amount is added to the base layer instead of the radical scavenger, it can be inferred that the average transmittance in the relevant region can be maintained at a high level.

[0082] From the results shown in Figures 10(A) to (C), resin 1 has a high average transmittance even when a radical scavenger is added, whereas resins 3 and 6 have a reduced average transmittance in the UVB region by adding a radical scavenger to the base layer, but have high transmittance in the UVA region, so it can be said that they transmit a certain level or more of ultraviolet light in the ultraviolet region.

[0083] Fig. 11 is a view showing Table B which compares the transmittance in each region of Resins 1, 3 and 6. The table shown in Fig. 11 compares the transmittance in the ultraviolet region of 280 to 380 nm (region 1) and 280 to 400 nm (region 2).

[0084] In the results shown in Figure 11(A), for Resin 1, with a UV-visible AR coating film layer and no radical scavenger, the average transmittance in region 1 is 88.9%, and the average transmittance in region 2 is 90.1%. For Resin 1 with a UV-visible AR coating film layer and a radical scavenger (LA-63P), the average transmittance in region 1 is 84.5%, and the average transmittance in region 2 is 86.2%.

[0085] In the results shown in Fig. 11(B), in the case of Resin 3 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in region 1 is 68.3%, and the average transmittance in region 2 is 72.9%. In the case of Resin 3 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-52), the average transmittance in region 1 is 48.6%, and the average transmittance in region 2 is 55.9%. In the case of Resin 3 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-57), the average transmittance in region 1 is 42.9%, and the average transmittance in region 2 is 50.3%.

[0086] 11(C), in the case of Resin 6 with an ultraviolet-visible light AR coating film layer and without a radical scavenger, the average transmittance in region 1 is 42.5%, and the average transmittance in region 2 is 51.0%. In the case of Resin 6 with an ultraviolet-visible light AR coating film layer and with a radical scavenger (LA-52), the average transmittance in region 1 is 33.1%, and the average transmittance in region 2 is 42.2%.

[0087] 9(C), 0.001 wt% of ultraviolet absorber (LA-46) was further added to resin 6 as a comparative example. In this case, in resin 6 with an ultraviolet-visible AR coating film layer, the average transmittance in region 1 is 29.3%, and the average transmittance in region 2 is 39.0%. Similarly, even if only an ultraviolet absorber with an appropriately adjusted amount is added to the base layer instead of the radical scavenger, it can be inferred that the average transmittance in the region can be maintained at a high level.

[0088] 11(A) to (C), even when a radical scavenger is added, resin 1 has a high average transmittance in the entire ultraviolet range. Although the average transmittance in the entire ultraviolet range of resins 3 and 6 decreases when a radical scavenger is added, as shown in FIG. 10, the transmittance in the UVA range is high, so it can be said that a certain level or more of ultraviolet light is transmitted in the entire ultraviolet range.

[0089] Next, the reflectance of each anti-reflection coating will be described. Fig. 12 is a diagram showing the reflectance of each anti-reflection coating applied to a test piece made of resin 6 with a substrate layer having a thickness of 2 mm. In the example shown in Fig. 12, in the case of resin 6 without an anti-reflection coating, the reflectance increases from about 5% to about 8% when the wavelength exceeds 330 nm.

[0090] In the resin 6 on which a coating film layer of visible light AR is formed, the reflectance is high, generally exceeding 10%, below visible light (e.g., 780 to 380 nm), and in the visible light region, the reflectance is 8% or less. Also, in the resin 6 on which a coating film layer of ultraviolet-visible light AR is formed, the reflectance is about 4% or less from the ultraviolet region of 280 nm to the visible region of 730 nm, and it is found that not only visible light but also ultraviolet light is transmitted well.

[0091] 12, the resin 6 on which the ultraviolet-visible AR coating film layer is formed has a reflectance of 5% or less in the wavelength region of 280 nm or more and 780 nm or less, and can be used as a coating film layer that transmits ultraviolet light well in the disclosed technology. In addition, the reflectance can be reduced more effectively with the ultraviolet-visible AR coating film layer than without the coating film layer, demonstrating the usefulness of the coating film layer.

[0092] Fig. 13 is a diagram showing the transmittance due to differences in the AR coating film layers on each side of the resin 3. In the example shown in Fig. 13, the transmittance in each of the following examples is shown for a test piece of a 1 mm-thick base layer made of resin 3. Substrate only Visible light AR coating on both sides Both sides have UV / visible AR coating layer Visible light AR coating layer on the front (convex surface), ultraviolet and visible light AR coating layer on the back (concave surface) There is an ultraviolet and visible light AR coating layer on the front side, and a visible light AR coating layer on the back side

[0093] In the examples shown in FIG. 13, an AR coating film layer that prevents reflection of visible light is formed in all cases, so that in the visible light region (e.g., 780 to 380 nm), the resin 3 with the AR coating film layer formed thereon has a higher transmittance than the resin 3 with only the base layer.

[0094] On the other hand, in the ultraviolet region (380 nm or less), particularly in the region of 360 to 380 nm, the transmittance of the resin 3 having an ultraviolet-visible AR coating film layer formed on at least one side is higher than the transmittance of the resin 3 having only the base layer. The resin 3 having a visible light AR coating film layer formed on the front side and an ultraviolet-visible AR coating film layer formed on the back side and the resin 3 having an ultraviolet-visible AR coating film layer formed on the front side and a visible light AR coating film layer formed on the back side had almost the same transmittance.

[0095] In addition, in the region of about 340 nm or less, even if an ultraviolet-visible AR coating film layer is formed on one side, the transmittance is lower than that of the substrate layer alone, which is considered to be because a visible AR coating film layer (see FIG. 12), which is likely to reflect ultraviolet light, is formed on the other side. However, the resin 3 having an ultraviolet-visible AR coating film layer formed on at least one side has a higher transmittance in the visible light region than the substrate layer alone, and exhibits an appearance with reduced glare on the lens surface, making it more suitable as a final eyeglass lens. Furthermore, the resin 3 having an ultraviolet-visible AR coating film layer formed on at least one side has a higher transmittance in the ultraviolet region than the resin 3 having visible AR coating film layers formed on both sides as seen in general eyeglass lenses, making it possible to make a practical eyeglass lens that is closer to the naked eye.

[0096] Furthermore, the resin 3 having the ultraviolet-visible light AR coating film layers formed on both sides has a higher transmittance in the range of approximately 315 nm or more than the resin 3 having only the base layer.

[0097] As described above, according to the second embodiment, as a result of carrying out experiments using various resins, it is possible to specify a substrate for the eyeglass lens in the present disclosure. For example, it is possible to form an eyeglass lens using at least any of resins 1 to 10 shown in FIG. 5 as the substrate layer. In the second embodiment, attention is focused on the average transmittance in the 360 ​​to 380 nm region in order to transmit ultraviolet light. By setting a threshold value (60%, 80%, etc.) for the total average transmittance of the coating film layer and substrate layer in this 360 to 380 nm region, it is possible to satisfy this condition and form a practical eyeglass lens that is close to the state seen by the naked eye.

[0098] In addition, in the substrate layer or the coating film layer in the second embodiment, the applicable materials and ingredients described in the first embodiment may be appropriately used. In addition, for example, a fluorine compound resin with high transmittance, specifically HMX10 by Daikin Industries, Ltd., may also be used as the substrate.

[0099] Moreover, the eyeglass lenses in the technology disclosed herein can be put to practical use as non-vision correcting lenses, for example.

[0100] Although the present invention has been described above using various embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0101] In addition, the present disclosure discloses a technology according to the following supplementary notes. [Appendix 1] A base layer; A coating film layer is coated on at least one surface of the base material layer, A spectacle lens, wherein the total average transmittance of the substrate layer and the coating film layer is 10% or more in a wavelength region of 280 nm or more and 400 nm or less. [Appendix 2] In a first wavelength region of 320 nm or more and 400 nm or less, the total average transmittance of the base material layer and the coating film layer is 15% or more, 2. The eyeglass lens according to claim 1, wherein the total average transmittance of the substrate layer and the coating film layer is 5% or more in a second wavelength region of 280 nm or more and less than 320 nm. [Appendix 3] In the first wavelength region, the total average transmittance of the base layer and the coating film layer is 55% or more, 3. The eyeglass lens according to claim 2, wherein the total average transmittance of the substrate layer and the coating film layer is 10% or more in the second wavelength region. [Appendix 4] In the first wavelength region, the total average transmittance of the base layer and the coating film layer is 85% or more, 4. The eyeglass lens according to claim 3, wherein the total average transmittance of the substrate layer and the coating film layer is 50% or more in the second wavelength region. [Appendix 5] 5. The eyeglass lens according to any one of claims 1 to 4, wherein the base layer is formed from at least one of an aliphatic polycarbonate, an aliphatic olefin polymer, an aliphatic acrylic resin, and an aliphatic nylon resin. [Appendix 6] 6. The eyeglass lens according to claim 5, wherein the aliphatic acrylic resin comprises an acrylic resin that transmits ultraviolet light. [Appendix 7] The eyeglass lens according to claim 5, wherein the aliphatic olefin polymer comprises at least one of a cycloolefin polymer and an aliphatic olefin polymer having no cyclic structure. [Appendix 8] The eyeglass lens according to any one of appendixes 1 to 7, wherein the coating film layer comprises a hard coating film layer formed from a material that does not contain an ultraviolet absorbent, and / or an anti-reflection coating layer formed from a material that does not contain an ultraviolet absorbent.

Claims

1. A resin base layer; A coating film layer is coated on at least one surface of the base material layer and includes an anti-reflection film for ultraviolet light and visible light, In a wavelength region of 360 nm or more and less than 380 nm, the total average transmittance of the base material layer and the coating film layer is 60% or more, A spectacle lens, wherein a total average transmittance of the substrate layer and the coating film layer is higher than an average transmittance of the substrate layer in a wavelength region of 280 nm or more and less than 315 nm.

2. 2. The eyeglass lens according to claim 1, wherein the total average transmittance of the substrate layer and the coating film layer is 80% or more in a wavelength region of 360 nm or more and less than 380 nm.

3. 2. The eyeglass lens according to claim 1, wherein the coating film layer has a reflectance of 10% or less in a wavelength region of 280 nm or more and less than 780 nm.

4. The eyeglass lens according to claim 3 , wherein the coating film layer is provided on the one surface of the base layer and on the surface opposite to the one surface.

5. The eyeglass lens according to claim 1 , wherein the base material layer has an average transmittance of 80% or more in a wavelength region of 360 nm or more and less than 380 nm.

6. The eyeglass lens according to claim 1 , wherein the substrate layer contains a radical scavenger and / or an ultraviolet absorbing agent.

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