TW202501029A - Eyeglass Lenses - Google Patents

Abstract

The present invention provides an eyeglass lens that appropriately responds to the opposite demands of wanting to be close to the state of naked eyes receiving natural light and wanting to cut off the wavelength of the UVB region. The eyeglass lens of the present invention has a substrate layer and a coating layer, the combined UVA average transmittance of the substrate layer and the coating layer is higher than the UVA average transmittance of the substrate layer, and the combined UVB average transmittance of the substrate layer and the coating layer is lower than the UVB average transmittance of the substrate layer.

Description

Eyeglass Lenses

The present invention relates to an ophthalmic lens.

Most existing eyeglass lenses are made of materials that cut off ultraviolet rays (e.g., see patent document 1) or lenses that do not allow ultraviolet rays to pass through (e.g., see patent document 2). On the other hand, it is also pointed out that sunlight has a positive impact on the physical and mental development of children, especially for children. When children do not receive sufficient sunlight, the risk of developing myopia increases (e.g., see non-patent document 1). [Prior technical literature] [Patent literature]

[Patent Document 1] Japanese Patent Publication No. 2009-209120 [Patent Document 2] International Publication No. 2019/188447 [Non-patent Document] [Non-patent Document 1] Five societies including the Japanese Ophthalmological Society, "Cautious Opinion on Children Wearing Blue Light Blocking Glasses," April 14, 2021, [retrieved January 27, 2022], Internet <https://www.gankaikai.or.jp/info/20210414_bluelight.pdf>

[The problem the invention is trying to solve]

Here, for users who wear glasses, in order for natural light including ultraviolet rays to reach their eyes, they must take off their glasses, and cannot obtain the effects of glasses such as correcting vision produced by the glasses.

In order to solve the above problems, it is considered to use a compound that allows ultraviolet rays to pass through to form the substrate of the ophthalmic lens. In order to meet the durability requirements of the ophthalmic lens, a coating is generally applied to the substrate. For such ophthalmic lenses of general structure, in order to allow natural light to reach the eyes as much as possible, it is required to reconsider the overall characteristics of the substrate and the coating, so that the ultraviolet rays that have been blocked until now can pass through.

In addition, ultraviolet rays include two types of ultraviolet rays: long-wavelength UVA (ultraviolet A) and short-wavelength UVB (ultraviolet B). Regarding UVB, the JIS standard stipulates that for refractive eyeglass lenses, the maximum transmittance in the solar ultraviolet B region is less than 5% of the visual transmittance (T 7333: 2018 (ISO 8980-3: 2013)). Therefore, in order to form eyeglass lenses that meet the JIS standard or are close to the JIS standard, it is also required to focus on the UVB region and cut off the wavelength of the UVB region.

Therefore, the purpose of the present invention is to provide an eyeglass lens that appropriately responds to the opposite demands of wanting to be close to the state of naked eyes receiving natural light and wanting to cut off the wavelength of the UVB region. [Technical means for solving the problem]

An ophthalmic lens of one aspect of the present invention comprises a substrate layer and a coating layer, wherein the combined UVA average transmittance of the substrate layer and the coating layer is higher than the UVA average transmittance of the substrate layer, and the combined UVB average transmittance of the substrate layer and the coating layer is lower than the UVB average transmittance of the substrate layer. [Effect of the invention]

According to the present invention, it is possible to provide an eyeglass lens that allows long-wavelength UVA ultraviolet rays to pass as much as possible and does not allow short-wavelength UVB ultraviolet rays to pass as much as possible.

The following detailed description of the implementation of the present invention is made with reference to the drawings. However, the implementation described below is for illustration only, and is not intended to exclude the application of various changes or technologies not expressly stated below. That is, the present invention can be implemented with various changes without departing from its main purpose. In addition, in the following drawings, the same or similar parts are marked with the same or similar symbols. The drawings are schematic and are not necessarily consistent with the actual dimensions or ratios. Sometimes, the drawings also include parts with different dimensional relationships or ratios.

[Implementation] <Existing ophthalmic lenses> FIG. 1 is a graph showing the light transmittance of each ophthalmic lens of the prior art (the ophthalmic lenses of the prior art are also collectively referred to as "existing lenses"). In the example shown in FIG. 1 , the following four lenses are used to measure the light transmittance. Lens A: Lens based on CR-39 (registered trademark) (allyl diglycol carbonate) manufactured by PPG Industries, Inc. (refractive index 1.50) Lens B: Lens based on thiourethane (refractive index 1.60) Lens C: Lens based on thiourethane (refractive index 1.67) Lens D: Lens based on thiourethane (refractive index 1.74)

Lenses A to D all have hard coating layers and anti-reflection coating layers formed on both sides of the substrate. Moreover, as shown in FIG1 , lenses A to D all cut off wavelengths shorter than 380 nm. It can be seen that lenses A to D all meet at least one of the following conditions: the substrate contains an ultraviolet absorber; the hard coating layer contains an ultraviolet absorber; and the anti-reflection coating layer contains an ultraviolet absorber.

Therefore, among many existing lenses, not limited to lenses for vision correction, the absorption wavelength of the lenses varies slightly depending on the lens manufacturer or material, but all lenses cut off wavelengths shorter than 380 nm.

Therefore, the inventors, in view of the effects of ultraviolet rays on the eyes that have been clearly known in recent years, thought of using eyeglass lenses to allow ultraviolet rays to pass through. However, as shown in FIG1 , most existing eyeglass lenses cut off ultraviolet rays, and there is no lens that the inventors need.

<Substrate in the ophthalmic lens of the invention> First, the substrate in the ophthalmic lens of the embodiment of the invention of this case is explained. In the ophthalmic lens of the embodiment, a substrate whose main material is a material that absorbs ultraviolet rays is not used. For example, as a material that absorbs ultraviolet rays, aromatic compounds or aliphatic compounds with a conjugated structure are known, so in the embodiment, a substrate whose main material is such compounds may not be used as an ophthalmic lens.

In the ophthalmic lens of the embodiment, for example, there is a base layer having a first compound as a main material other than a compound that absorbs ultraviolet rays of a prescribed % or more. The material that absorbs ultraviolet rays of a prescribed % or more includes the above-mentioned aromatic compound as an example. In addition, the base layer may also contain an aromatic compound within the range that does not hinder the purpose of the embodiment.

Thus, since the base layer is composed of the first compound other than the compound that absorbs ultraviolet rays at a prescribed % or more, it is possible to at least prevent the transmission of ultraviolet rays from being largely blocked by the base layer of the ophthalmic lens. Therefore, ultraviolet rays pass through the ophthalmic lens, and light close to natural light including ultraviolet rays reaches the eyes.

Furthermore, in the embodiment, the ultraviolet light is, for example, in the wavelength range of 280 to 400 nm. Among them, 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 can be set at 315 nm, and the upper limit of UVA can be set at 380 nm. In the eyeglass lens in the embodiment, the lens is constructed in a manner that the wavelength of the UVA region is transmitted and the wavelength of the UVB region is cut off.

The first compound used to form the substrate layer is, for example, a compound other than an aromatic compound, and may include at least one of an aliphatic polycarbonate, an aliphatic olefin polymer, an aliphatic acrylic resin, and an aliphatic nylon resin.

The substrate formed of aliphatic polycarbonate includes, for example, at least one of CR-39 (registered trademark) manufactured by PPG and DURABIO (registered trademark) manufactured by Mitsubishi Chemical. CR-39 (registered trademark) is a linear aliphatic polycarbonate without an aromatic ring, so its ultraviolet absorption function is relatively small. In addition, DURABIO (registered trademark) is a polycarbonate that uses isosorbide as a partial biomaterial. Since the diol copolymerized with isosorbide is also alicyclic and does not have an aromatic ring, it is believed that the ultraviolet absorption function is relatively small.

Aliphatic olefin polymers include, for example, at least one of cycloolefin polymers (alicyclic olefin polymers) and aliphatic olefin polymers without a cyclic structure. The substrate formed using the cycloolefin polymer may include, for example, any of APEL (registered trademark) manufactured by Mitsui Chemicals (refractive index 1.544, Abbe number 56), ZEONEX (registered trademark) manufactured by Zeon Japan (refractive index 1.509-1.535), and ARTON (registered trademark) manufactured by JSR Corporation (refractive index 1.513-1.516, Abbe number 56 or 57).

The substrate formed of an aliphatic olefin polymer having no ring structure may include, for example, TPX (registered trademark) (compound name: polymethylpentene) (refractive index: 1.46) commercially available from Mitsui Chemicals, Inc.

For example, the substrate formed of aliphatic acrylic resin can adopt "UV-transmitting PMMA lens" (refractive index of about 1.49, Abbe number 55) manufactured by Japan Special Optical Resins Co., Ltd. PMMA is the abbreviation of polymethyl methacrylate. UV-transmitting PMMA is an acrylic resin that allows UV rays to pass through.

<Coating> The ophthalmic lens may have a hard coating layer (also referred to as "hard coating layer", "hard coating film", or "hard coating layer") formed on at least one side of the substrate layer. The ophthalmic lens in the embodiment may have a hard coating layer formed of a material that does not contain an ultraviolet absorber and coated on at least one side of the substrate layer. The hard coating layer may be formed, for example, by uniformly coating a hard coating liquid on the surface of the substrate layer, using a resin that does not contain aromatic compounds.

For example, an ophthalmic lens may use an organosiloxane resin preferably containing inorganic oxide particles as a hard coating layer. The organosiloxane resin is preferably obtained by hydrolyzing and condensing an alkoxysilane. Specific examples of the organosiloxane resin include γ-glyceryloxypropyltrimethoxysilane, γ-glyceryloxypropyltriethoxysilane, methyltrimethoxysilane, ethyl silicate, or a combination thereof. The hydrolysis condensate of alkoxysilane is produced by hydrolyzing the alkoxysilane compound or a combination thereof with an acidic aqueous solution such as hydrochloric acid.

In addition, the material of the inorganic oxide microparticles includes, for example, single sols of zinc oxide, silicon dioxide (silicon dioxide microparticles), aluminum oxide, titanium oxide (titanium oxide microparticles), zirconium oxide (zirconia microparticles), tin oxide, curium oxide, antimony oxide, tungsten oxide, and zirconium oxide, or a mixed crystal of any two or more thereof.

From the perspective of ensuring the transparency of the hard coating layer, the diameter of the inorganic oxide microparticles is preferably 1 nm to 100 nm, and more preferably 1 nm to 50 nm. Furthermore, from the perspective of ensuring the hardness or toughness of the hard coating layer to an appropriate degree, the amount (concentration) of the inorganic oxide microparticles is preferably 40 wt % to 60 wt % of all the components of the hard coating layer.

In addition, the hard coating liquid is added with at least one of acetylacetonate metal salt and ethylenediaminetetraacetic acid metal salt as a hardening catalyst, and further, according to the requirements of ensuring adhesion to the substrate or easy formation, giving the required (semi) transparent color, etc., a surfactant, a colorant, a solvent, etc. are added.

The inorganic oxide (metal oxide) in the inorganic oxide microparticles is selected to be one that does not absorb as much as possible in the visible light range. This is based on the following viewpoints: to ensure high transmittance in the entire visible light range, to ensure that the difference in color perceived when the lens is worn is extremely small compared to the color perceived by the naked eye. From this viewpoint, the inorganic oxide is preferably an oxide of one or more metals other than Ti (titanium) and Ce (cathode). Ti (titanium) oxide or Ce (cathode) oxide absorbs in the visible light range (especially the short-wavelength side), so these are excluded from the preferred metal oxides.

As examples of preferred metal oxides, any one of the oxides of Sb (antimony), Sn (tin), Si (silicon), Al (aluminum), Ta (tantalum), La (lumi), Fe (iron), Zn (zinc), W (tungsten), Zr (zirconium), and In (indium) or a combination thereof can be cited.

The physical film thickness of the hard coating layer is preferably set to be not less than 0.5 μm (micrometer) and not more than 4.0 μm. The lower limit of the film thickness range is determined by the following circumstances: if it is thinner, it is difficult to obtain sufficient hardness. On the other hand, the upper limit is determined by the following circumstances: if it is thicker, the possibility of problems related to physical properties such as cracks and brittleness increases dramatically, and the influence of inorganic oxide microparticles on the absorption (reduction of transmittance) in the visible light range increases. Furthermore, in addition to the above-mentioned thermosetting coating agents, the hard coating agent used for the hard coating layer can also use the well-known light-curing coating agent.

In addition, the ophthalmic lens in the embodiment may have an anti-reflection film layer (also referred to as "anti-reflection film" or "anti-reflection layer"), which is coated on at least one side of the substrate layer to allow the wavelength of the UVA region to pass through and reflect the wavelength of the UVB region. The anti-reflection film layer may be formed on the substrate layer, preferably on the hard coating film layer. In addition, the anti-reflection film layer may be formed of an optical multi-layer film.

From the perspective of ensuring the anti-reflection function, it is preferably formed in a manner having a substantially flat and relatively high transmittance distribution in the UVA region and the entire visible light region. The relatively high transmittance is, for example, 90% or more.

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 (5 layers in total, 7 layers in total, etc.) as a whole. Furthermore, it is preferred that when the layer closest to the substrate side (the layer closest to the substrate) is set as 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 layer or the high refractive index layer is formed by vacuum evaporation, ion assisted evaporation, ion plating, sputtering, etc.

<Spectacle lens> For the spectacle lens of the embodiment, various examples of substrate resins that are candidates for the substrate layer of the spectacle lens of the present invention are listed below. Base resin 1: ACRYPET (registered trademark) VH000 Base resin 2: ZEONEX (registered trademark) K22R Base resin 3: ARTON (registered trademark) F3500 Base resin 4: ACRYLITE (registered trademark) L000 Base resin 5: ZEONEX (registered trademark) K26R Base resin 6: TPX (registered trademark) RT18 Base resin 7: APEL (registered trademark) 5014XH Base resin 8: CR-39 (registered trademark) Base resin 9: MR-8 (registered trademark) Resin 10 for substrate: MR-10 (registered trademark)

The above-mentioned examples of substrate resins are all candidates for the substrate layer. Among these resins, substrate resins 1 to 3 are described as resins that transmit wavelengths in the UVA region and cut wavelengths in the UVB region. In addition, the inventors varied the type of anti-reflection film layer (also referred to as "AR (Anti Reflection) coating") of each substrate resin of the ophthalmic lens of the embodiment, and conducted experiments and investigations on the total transmittance of the resin (substrate layer) and the AR coating.

The AR coating used in the experiment includes a visible light AR coating that prevents visible light reflection (or transmission), and a UVA visible light AR coating that prevents UVA area and visible light area reflection. In addition, the substrate layer used in the experiment is a 2 mm thick test piece including only substrate resin and substrate resin added with free radical scavenger and/or ultraviolet absorber. The free radical scavenger or ultraviolet absorber uses Adekastab (registered trademark) (LA-63P, LA-52, LA-57 or LA-46) of ADEKA Corporation, and 0.2 wt%, 0.003 wt%, or 0.005 wt% is added to each substrate layer. The free radical scavenger can improve the durability of the lens to prevent lens degradation.

FIG2 is a graph showing an example of the total transmittance of each substrate layer and each AR coating layer based on the substrate resin 1. In the curve graph shown in FIG2, the vertical axis represents transmittance and the horizontal axis represents wavelength, showing the transmittance of each combination mode of the following substrate resin and AR coating. In the following, "transmittance" represents the transmittance of a specified wavelength or an arbitrary wavelength within a specified area, and "average transmittance" represents the average transmittance of the transmittance at each wavelength within a specified area. Specimen 11: Resin 1 for substrate without AR coating Specimen 12: Resin 1 for substrate with visible light AR coating formed on both sides Specimen 13: Resin 1 for substrate with UVA visible light AR coating formed on both sides Specimen 14: Resin 1 for substrate without AR coating and with LA-63P (0.2 wt%) added Specimen 15: Resin 1 for substrate with visible light AR coating formed on both sides and with LA-63P (0.2 wt%) added Specimen 16: Resin 1 for substrate with UVA visible light AR coating formed on both sides and with LA-63P (0.2 wt%) added

Regarding sample 11, the transmittance in the region above 330 nm is about 90%, and the transmittance in the region below 330 nm decreases as the wavelength becomes shorter, and the transmittance at 280 nm is less than 65%.

Regarding sample 12, in order to prevent reflection of visible light, the transmittance is above 90% in the region exceeding 380 nm. However, since light other than visible light is not particularly considered, the transmittance decreases as the wavelength becomes shorter in the region below about 400 nm, and the transmittance is about 60% at 280 nm.

Regarding sample 13, in order to prevent reflection of the UVA region and visible light, the transmittance in the region above 330 nm is about 90% or more. However, since the UVB region is not particularly considered, the decrease in transmittance in the region below about 315 nm increases as the wavelength becomes shorter, and the transmittance at 280 nm is less than 40%.

Regarding sample 14, the transmittance in the region above 380 nm is about 90%, and in the region above 315 nm and below 380 nm, the transmittance decreases as the wavelength becomes shorter, and the transmittance is above 80%. The transmittance below 315 nm further decreases, and the transmittance at 280 nm is less than 65%. According to this result, by adding a free radical scavenger to the substrate layer, the transmittance can be reduced at wavelengths below visible light.

Regarding the sample 15, in order to prevent the reflection of visible light, the transmittance is basically the same as that of the sample 12. However, due to the influence of the radical scavenger, the transmittance of the sample 15 at wavelengths below 330 nm is further reduced than that of the sample 12, and the transmittance at 280 nm is less than 50%.

Regarding the sample 16, the transmittance in the region above 380 nm is substantially the same as that of the sample 13. However, due to the influence of the free radical scavenger, the transmittance of the sample 16 is lower than that of the sample 13 by approximately % in the region below 380 nm.

According to the example shown in FIG. 2 , the transmittance of the substrate resin 1 in the UVB region is relatively lower than that in the UVA region or the visible light region, and therefore it is suitable for the technology of the present invention (for example, refer to sample 11). Moreover, compared with the case of only the substrate resin 1 or the sample with the visible light AR coating layer formed thereon, by applying the UVA visible light AR coating layer, the transmittance in the UVA region can be increased, and the transmittance in the UVB region can be reduced (for example, refer to samples 11, 12, and 13). Furthermore, by adding a free radical scavenger (LA-63P) to the substrate resin 1, the transmittance in the UVB region can be particularly reduced (for example, refer to samples 13 and 16).

FIG3 is a graph showing an example of the reflectance of test pieces 11 to 16. In the curve graph shown in FIG3, the vertical axis represents the reflectance and the horizontal axis represents the wavelength, showing the reflectance of each test piece. As for the reflectance of test pieces 11 and 14, since neither has an AR coating, the reflectance is roughly flat (<10%) in the range of 280 nm to 780 nm. Hereinafter, "reflectance" means the reflectance at a specified wavelength or an arbitrary wavelength within a specified area, and "average reflectance" means the average reflectance of the reflectance at each wavelength within a specified area.

Regarding the reflectivity of the sample 12 and the sample 15, the average reflectivity in the visible light region (380-780 nm) is less than 5%, and in particular, the average reflectivity in the region of 400-630 nm is less than 3%. On the other hand, in the visible light AR coating, since the region below 380 nm is not particularly considered, the reflectivity has a characteristic of approximately normal distribution with a maximum value of about 27% at about 300 nm in the region below 380 nm.

Since the UVA visible light AR coating is applied on both sides of the specimen 13 and the specimen 16, the reflectivity is less than 10% in the region above 330 nm. On the other hand, in the region below 330 nm, especially the UVB region, the reflectivity of the UVA visible light AR coating is not specifically considered, so the reflectivity increases as the wavelength becomes shorter, and the reflectivity is about 30% or more at about 280 nm.

As shown in FIG. 3 , the UVA visible light AR coating prevents reflection of wavelengths in the UVA region and the visible light region, but since the UVB region is not particularly considered, the reflectivity increases as the wavelength becomes shorter. Therefore, when designing a lens for eyeglasses that allows the UVA region and the visible light region to pass as much as possible and prevents the UVB region from passing as much as possible, it is preferred to apply the UVA visible light AR coating on at least one side. In addition, for the UVB region, such as test pieces 13 and 16, the combined average reflectivity of the coating layer and the substrate resin 1 only needs to be higher than the average reflectivity of test piece 11 (substrate resin 1 only). For example, a coating layer having a reflectivity characteristic with a maximum value in the UVB region can be formed. Thus, by selecting a coating layer having an average reflectivity for wavelengths in the UVB region higher than the average reflectivity for wavelengths in other regions and forming the coating layer on the base material layer, light in the UVB region can be actively cut off.

FIG4 is a graph showing an example of the total transmittance of each base layer and each AR coating layer based on the base resin 2. In the curve graph shown in FIG4, the vertical axis represents transmittance and the horizontal axis represents wavelength, showing the transmittance of each combination mode of the following base resin and AR coating. Specimen 21: Resin 2 for substrate without AR coating Specimen 22: Resin 2 for substrate with visible light AR coating formed on both sides Specimen 23: Resin 2 for substrate with UVA visible light AR coating formed on both sides Specimen 24: Resin 2 for substrate without AR coating and with LA-52 (0.2 wt%) added Specimen 25: Resin 2 for substrate with visible light AR coating formed on both sides and with LA-52 (0.2 wt%) added Specimen 26: Resin 2 for substrate with UVA visible light AR coating formed on both sides and with LA-52 (0.2 wt%) added Specimen 27: Resin 2 for substrate without AR coating and with LA-57 (0.2 wt%) of the substrate resin 2 Specimen 28: A substrate resin 2 with a visible light AR coating formed on both sides and LA-57 (0.2 wt%) added Specimen 29: A substrate resin 2 with a UVA visible light AR coating formed on both sides and LA-57 (0.2 wt%) added

The transmittance of the sample 21 is fixed at about 90% in the region above about 360 nm. The transmittance of the sample 21 drops sharply to about 60% in the region from about 320 nm to about 360 nm as the wavelength becomes shorter. In addition, the transmittance of the sample 21 drops slowly in the region from about 300 nm to 320 nm as the wavelength becomes shorter, and then drops sharply to about 0% in the region from about 280 nm to 300 nm as the wavelength becomes shorter.

Regarding sample 22, in order to prevent reflection of visible light, the transmittance is above 90% in the region exceeding 380 nm. However, since light other than visible light is not particularly considered, the transmittance drops sharply to about 45% as the wavelength becomes shorter in the region of about 400 nm to about 315 nm, and then drops sharply to about 0% at 280 nm.

For sample 23, in order to prevent reflection of UVA and visible light, the transmittance is about 90% or more in the region above about 350 nm. For UVA visible light AR coating, since the UVB region is not particularly considered in terms of reflection, the transmittance of resin 23 decreases as the wavelength becomes shorter in the region below about 350 nm, and the transmittance is approximately 0% at 280 nm.

Regarding sample 24, the transmittance is about 90% in the region above about 430 nm, and decreases to about 80% as the wavelength decreases in the region from about 350 nm to about 430 nm, and then sharply decreases to about 20% as the wavelength decreases in the region from about 320 nm to about 350 nm. The transmittance of sample 24 is fixed at about 20% in the region from 300 nm to 320 nm, and decreases to 0% as the wavelength decreases in the region from 280 nm to 300 nm. According to the results, by adding a free radical scavenger (LA-52) to the substrate layer, the transmittance can be reduced at wavelengths below visible light, especially in the region from 300 nm to about 380 nm.

Regarding the sample 25, in order to prevent the reflection of visible light, the transmittance in the region above about 370 nm is substantially the same as that of the sample 22. However, due to the influence of the radical scavenger, the transmittance of the sample 25 is further reduced than that of the sample 22 and the sample 24 at wavelengths below about 370 nm.

The sample 26 basically showed the same transmittance as the sample 25, but the transmittance of the sample 26 formed with the UVA visible light AR coating was higher than that of the sample 25 in the region of about 300 nm to about 370 nm.

Regarding the sample 27, the transmittance of the sample 27 is roughly the same as the transmittance of the sample 24 in the region above about 380 nm, and the transmittance of the sample 27 is lower than the transmittance of the sample 24 in the region of about 300 nm to about 380 nm, and the maximum is as low as about 10%. This means that the transmittance of the sample changes according to the type of free radical scavenger added. Further, it means that by adding the free radical scavenger LA-57, the transmittance in the UVB region is significantly reduced, which is suitable for the invented technology.

Regarding the sample 28 and the sample 29, both samples showed the same transmittance. In the region of about 300 nm to about 370 nm, the transmittance of the sample 29 formed with the UVA visible light AR coating was higher than that of the sample 28.

According to the example shown in FIG. 4 , the transmittance of the substrate resin 2 in the UVB region is relatively lower than that in the UVA region or the visible light region, and therefore it is suitable for the technology of the present invention (for example, refer to sample 21 ). In addition, the transmittance of the substrate resin 2 in the UVB region is lower than that of the substrate resin 1 , and therefore it is more suitable for the technology of the present invention (for example, refer to sample 21 in FIG. 4 and sample 11 in FIG. 2 ). In addition, by applying the visible light AR coating to the substrate resin 2 , the transmittance in the UVB region can be reduced only compared to the substrate resin 2 (for example, refer to sample 24 and sample 25 ). Furthermore, compared with the case of only the substrate resin 2 or the specimen with the visible light AR coating layer formed thereon, by applying the UVA visible light AR coating, the transmittance in the UVA region can be increased and the transmittance in the UVB region can be reduced (for example, refer to specimens 21, 22, and 23). Furthermore, by adding a free radical scavenger (LA-57 or LA-52) to the substrate resin 2, the transmittance in the UVB region can be reduced (for example, refer to specimens 21 to 23 and specimens 24 to 29). Furthermore, for the added free radical scavenger, the transmittance of LA-57 can be made lower than that of LA-52 (for example, refer to specimens 24 to 26 and specimens 27 to 29).

FIG5 is a graph showing an example of the reflectance of the test pieces 21 to 29. In the curve graph shown in FIG5, the vertical axis represents the reflectance and the horizontal axis represents the wavelength, showing the reflectance of each test piece. As for the reflectance of the test pieces 21, 24, and 27, since none of them has an AR coating, the reflectance is generally flat (<10%) in the range of about 350 nm to 780 nm, and the reflectance further decreases in the range of 280 nm to about 350 nm.

The reflectivity of the specimen 22, the specimen 25, and the specimen 28 has a reflectivity with a substantially similar tendency in the visible light region (380 nm to 780 nm), and the average reflectivity is less than 5%, especially in the region of about 400 nm to about 630 nm, the average reflectivity is less than 3%. On the other hand, in the visible light AR coating, since the region below 380 nm is not particularly considered, the reflectivity increases. In addition, the reflectivity has a characteristic of approximately normal distribution in the region below 380 nm, the specimen 22 has a maximum value of about 20% at about 310 nm, the specimen 25 and the specimen 28 have a maximum value of about 21 to 23% at about 290 nm, and the peak wavelength and the maximum value are slightly different in the specimens 22, 25, and 28.

Specimen 23, Specimen 26, and Specimen 29 have approximately the same reflectivity in the region of 280 nm to 780 nm. In addition, regarding these reflectivities, since UVA visible light AR coating is applied on both sides, the average reflectivity is about 25% at 280 nm and below 5% in the region of about 330 nm to 780 nm. Furthermore, in the region below about 350 nm, it is believed that the reflectivity of specimens 26 and 29 is slightly lower than that of specimen 23 due to the influence of the free radical scavenger.

In the example shown in FIG. 5 , similarly to the example shown in FIG. 3 , the UVA visible light AR coating prevents reflection of wavelengths in the UVA region and the visible light region, but since the UVB region is not particularly considered, the reflectivity increases as the wavelength becomes shorter. In addition, the reflectivity shown in FIG. 5 tends to be lower than the reflectivity shown in FIG. 3 as a whole. It is believed that the reason is that the substrate resin 2 has the characteristic of absorbing light more than the substrate resin 1. Furthermore, for the UVB region, such as test pieces 23, 26, and 29, as long as the combined average reflectivity of the coating layer and the substrate resin 2 is higher than the average reflectivity of the test piece 21 (only the substrate resin 2), it will be sufficient. For example, a coating layer having a reflectivity characteristic with a maximum value in the UVB region can be formed. Thus, by selecting a coating layer having an average reflectivity for wavelengths in the UVB region higher than the average reflectivity for wavelengths in other regions and forming the coating layer on the base material layer, light in the UVB region can be actively cut off.

FIG6 is a graph showing an example of the transmittance of each substrate layer with UV absorber (LA-46) and/or radical scavenger (LA-52) added to the substrate resin 3. In the curve graph shown in FIG6, the vertical axis represents transmittance and the horizontal axis represents wavelength, showing the transmittance of each substrate resin described below. None of the test pieces has an AR coating. Specimen 31: Resin 3 for substrate only Specimen 32: Resin 3 for substrate with LA-52 (0.2 wt%) added Specimen 33: Resin 3 for substrate with LA-52 (0.2 wt%) and LA-46 (0.001 wt%) added Specimen 34: Resin 3 for substrate with LA-46 (0.003 wt%) added Specimen 35: Resin 3 for substrate with LA-46 (0.005 wt%) added

By adding an ultraviolet absorber (LA-46) and/or a free radical scavenger (LA-52) to the base resin 3, even without an AR coating, it is possible to allow the UVA region to pass as much as possible while preventing the UVB region from passing. For example, in the UVB region, the transmittance of the sample 31 without an additive exceeds 10% at about 295 nm. In contrast, the transmittances of the samples 32 to 35 are all below 5%, which can prevent the light in the UVB region from passing.

Regarding additives, ultraviolet absorbers can reduce transmittance more than free radical scavengers (for example, refer to test pieces 32 and test pieces 34-35). Regarding the amount of ultraviolet absorbers added, in test pieces 34-35, there is no difference in transmittance in the UVB region, but in the UVA region, the transmittance of 0.005 wt% is slightly lower than 0.003 wt%. Therefore, if the amount of ultraviolet absorbers added is increased, the transmittance in the UVA region decreases. Therefore, according to the purpose, the preferred amount of addition is about 0.003 wt% or less (for example, refer to test piece 33).

FIG7 is a graph showing an example of transmittance when each resin shown in FIG6 is formed with a UVA visible light AR coating. In the curve graph shown in FIG7, the vertical axis represents transmittance and the horizontal axis represents wavelength, showing each transmittance of each resin described below. Specimen 31U: Specimen 31 with a UVA visible light AR coating formed on both sides Specimen 32U: Specimen 32 with a UVA visible light AR coating formed on both sides Specimen 33U: Specimen 33 with a UVA visible light AR coating formed on both sides Specimen 34U: Specimen 34 with a UVA visible light AR coating formed on both sides Specimen 35U: Specimen 35 with a UVA visible light AR coating formed on both sides

As shown in FIG. 7 , even when the UVA visible light AR coating is applied to the test pieces 31 to 35 , the transmittance trend is basically unchanged, the transmittance in the visible light region increases, and the average transmittance is above 95%.

According to FIG. 6 and FIG. 7, by adding a free radical scavenger and/or an ultraviolet absorber to the base resin 3 and applying the UVA visible light AR coating on both sides, the UVB region can be prevented from passing through, the UVA region can be passed through as much as possible, and the visible light region can be substantially passed through. Furthermore, it can be seen that the base resin 3 itself can also suppress the wavelength of the UVB region to a transmittance of about 15% or less, and is therefore suitable for the technology of the present invention.

FIG8 is a graph showing an example of transmittance when each AR coating is formed on the substrate resin 3. In the curve graph shown in FIG8, the vertical axis represents transmittance and the horizontal axis represents wavelength, showing each transmittance of each resin described below. Specimen 31: Specimen 31 without AR coating Specimen 31A: Specimen 31 with visible light AR coating formed on both sides Specimen 31U: Specimen 31 with UVA visible light AR coating formed on both sides

The transmittance of the sample 31 shown in FIG8 is the same as the transmittance of the sample 31 shown in FIG6. Since the visible light AR coating is formed on both sides of the sample 31A, the transmittance in the visible light region of about 380 nm to 780 nm is higher than the transmittance of the sample 31. On the other hand, since the region below about 380 nm is not particularly considered, the average transmittance in the region of about 330 nm to about 380 nm is lower than the average transmittance of the sample 31.

Since the UVA visible light AR coating is formed on both sides of the test piece 31U, the transmittance in the visible light region (380 nm to 780 nm) is higher than the transmittance of the test piece 31. In addition, in order to prevent the reflection of the wavelength in the UVA region, the average transmittance of the UVA region of the test piece 31U is higher than the transmittance of the test piece 31A having the visible light AR coating formed on both sides. Furthermore, it can be seen that any of the test pieces shown in FIG. 8 can suppress the wavelength in the UVB region to a transmittance of about 15% or less, and therefore is suitable for the technology of the present invention.

Fig. 9 is a graph showing a comparative example of the reflectance of the test pieces 31 formed with various AR coatings. In the graph shown in Fig. 9, the vertical axis represents the reflectance and the horizontal axis represents the wavelength, showing the reflectance of each test piece. The test pieces compared in Fig. 9 are the same as the test pieces shown in Fig. 8.

Since the sample 31 has no AR coating, the reflectivity is substantially flat (<10%) in the range of about 350 nm to 780 nm, and the reflectivity is about 5% in the range of 280 nm to 330 nm.

The average reflectivity of the sample 31A in the visible light region (380 nm to 780 nm) is less than 5%, and in particular, the average reflectivity in the region of about 400 nm to about 630 nm is less than 2%. On the other hand, in the visible light AR coating, the reflectivity increases because the region below 380 nm is not particularly considered. For example, the maximum reflectivity exceeds 17% at about 300 nm.

The average reflectivity of the sample 31U in the region below about 300 nm is about 5%. Similar to the examples shown in Figures 3 and 5, the UVA visible light AR coating prevents reflection of wavelengths in the UVA region and the visible light region, but since the UVB region is not particularly considered, in the region from 280 nm to about 330 nm, the reflectivity increases as the wavelength becomes shorter, and increases to about 8% at 280 nm.

According to FIG. 9 , the reflectivity of the substrate resin 3 is lower than the reflectivity of the substrate resin 2 shown in FIG. 5 . The reason is believed to be that the substrate resin 3 itself has the characteristic of absorbing light (especially light in the ultraviolet region) more than the substrate resin 2. Furthermore, for the UVB region, as long as the combined average reflectivity of the coating layer and the substrate resin 3 is higher than the average reflectivity of the test piece 31 (only the substrate resin 3), it will be sufficient. For example, a coating layer having a reflectivity characteristic with a maximum value in the UVB region can be formed. Thus, by selecting a coating layer whose average reflectivity for the wavelength of the UVB region is higher than the average reflectivity for the wavelength of other regions and forming it on the substrate layer, the light in the UVB region can be actively cut off.

FIG10 is a graph showing a comparative example of the reflectance of the test piece 32 and the test piece 35 formed with each AR coating. In the curve graph shown in FIG10, the vertical axis represents the reflectance and the horizontal axis represents the wavelength, showing the reflectance of each test piece. As for the reflectance of only the test piece 32 and the test piece 35, since neither has an AR coating, the reflectance is roughly flat (<10%) in the range of 380 nm to 780 nm, and the reflectance further decreases in the range of 280 nm to 380 nm, and is about 5% at 280 nm to 330 nm.

The test pieces 32A and 35A coated with visible light AR coating on both sides have approximately the same reflectivity in the visible light region, but in the wavelength region of 280 nm to about 320 nm including UVB, the reflectivity of the test piece 32A without ultraviolet absorber is higher.

As described above, in the visible light AR coating, the reflectivity increases because the region below 380 nm is not particularly considered. In addition, the reflectivity has a characteristic of approximately normal distribution in the region below 380 nm, with the maximum value of about 22% for the sample 32A at about 290 nm and the maximum value of about 15% for the sample 35A at about 330 nm, and the peak wavelengths and maximum values of each are slightly different.

The test pieces 32U and 35U coated with UVA visible light AR coating on both sides have approximately the same reflectivity in the region of about 350 nm to 780 nm. In addition, since the UVA visible light AR coating is coated on both sides, the reflectivity is an average reflectivity of less than 5%. Furthermore, the reflectivity of the test piece 32U in the region below about 330 nm increases as the wavelength becomes shorter, and the reflectivity of the test piece 35U in the region below about 350 nm increases as the wavelength becomes shorter.

In the example shown in FIG. 10 , similarly to the examples shown in FIG. 3 and FIG. 5 , the UVA visible light AR coating prevents reflection of wavelengths in the UVA region and the visible light region, but since the UVB region is not particularly considered, the reflectivity increases as the wavelength becomes shorter.

Fig. 11 is a graph showing a comparative example of the reflectance of each test piece formed with a UVA visible light AR coating. In the graph shown in Fig. 11, the vertical axis represents the reflectance and the horizontal axis represents the wavelength, showing the reflectance of each test piece.

In the example shown in FIG. 11 , a UVA visible light AR coating is formed on both sides, so there is no significant difference in the tendency of reflectivity. Therefore, by applying the UVA visible light AR coating on both sides, the wavelength of the UVB region can be prevented from passing through as much as possible, and the wavelength of the UVA region and the visible light region can be passed through as much as possible. In addition, the UVA visible light AR coating used in the experiment shown in FIG. 11 does not specifically consider the UVB region, so the reflectivity increases in the UVB region. That is, for the UVB region, even if it is not specifically considered, the reflectivity increases. Therefore, when a UVA visible light AR coating designed to further increase the reflectivity is formed on the substrate layer, the wavelength of the UVB region can be further cut off.

Fig. 12 is a table showing a comparison of the transmittance of each substrate resin in each wavelength region. In the table shown in Fig. 12A, the transmittance of the test pieces 11 to 16 in the ultraviolet region of 280 to 315 nm (UVB region) and 315 to 380 nm (UVA region) is compared.

In the results shown in FIG. 12A , in sample 11 (resin 1 for substrate only), the average transmittance in the UVA region was 90.4%, and the average transmittance in the UVB region was 78.9%. In sample 12 (resin 1 for substrate with visible light AR coating formed), the average transmittance in the UVA region was 79.3%, and the average transmittance in the UVB region was 63.1%. In sample 13 (resin 1 for substrate with UVA visible light AR coating formed), the average transmittance in the UVA region was 91.2%, and the average transmittance in the UVB region was 64.2%.

In addition, in the sample 14 (resin 1 for substrate with LA-63P (0.2 wt%) added), the average transmittance in the UVA region was 86.5%, and the average transmittance in the UVB region was 74.6%. In the sample 15 (resin 1 for substrate with visible light AR coating formed on both sides and LA-63P (0.2 wt%) added), the average transmittance in the UVA region was 77.4%, and the average transmittance in the UVB region was 55.4%. In the sample 16 (resin 1 for substrate with UVA visible light AR coating formed on both sides and LA-63P (0.2 wt%) added), the average transmittance in the UVA region was 87.0%, and the average transmittance in the UVB region was 57.6%.

In the results shown in FIG. 12B , in sample 21 (resin 2 for substrate only), the average transmittance in the UVA region was 81.4%, and the average transmittance in the UVB region was 36.2%. In sample 22 (resin 2 for substrate with visible light AR coating formed), the average transmittance in the UVA region was 74.3%, and the average transmittance in the UVB region was 28.9%. In sample 23 (resin 2 for substrate with UVA visible light AR coating formed), the average transmittance in the UVA region was 82.4%, and the average transmittance in the UVB region was 32.2%.

In addition, in the sample 24 (substrate resin 2 with LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 63.9%, and the average transmittance in the UVB region was 13.1%. In the sample 25 (substrate resin 2 with visible light AR coating formed on both sides and LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 61.0%, and the average transmittance in the UVB region was 10.1%. In the sample 26 (substrate resin 2 with UVA visible light AR coating formed on both sides and LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 65.7%, and the average transmittance in the UVB region was 13.0%.

In addition, in the sample 27 (substrate resin 2 with LA-57 (0.2 wt%) added), the average transmittance in the UVA region was 57.7%, and the average transmittance in the UVB region was 6.7%. In the sample 28 (substrate resin 2 with visible light AR coating formed on both sides and LA-57 (0.2 wt%) added), the average transmittance in the UVA region was 55.4%, and the average transmittance in the UVB region was 5.5%. In the sample 29 (substrate resin 2 with UVA visible light AR coating formed on both sides and LA-57 (0.2 wt%) added), the average transmittance in the UVA region was 59.1%, and the average transmittance in the UVB region was 6.7%.

According to the results shown in FIG. 12B , for example, by adding a radical scavenger to the substrate resin 2 and forming a UVA visible light AR coating on both sides, the transmittance in the UVA region can be made about 60% or more and the transmittance in the UVB region can be made about 13% or less. In particular, if LA-57 is added as a radical scavenger, the transmittance in the UVB region can be made lower than LA-52 and can be made less than 7%.

In the results shown in FIG. 12C , in the sample 31 (substrate resin 3 only), the average transmittance in the UVA region is 57.4%, and the average transmittance in the UVB region is 7.6%. In the sample 31A (substrate resin 3 with visible light AR coating formed), the average transmittance in the UVA region is 53.0%, and the average transmittance in the UVB region is 6.9%. In the sample 31U (substrate resin 3 with UVA visible light AR coating formed), the average transmittance in the UVA region is 58.4%, and the average transmittance in the UVB region is 7.2%.

In addition, in the test piece 32 (substrate resin 3 with LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 47.4%, and the average transmittance in the UVB region was 2.9%. In the test piece 32A (substrate resin 3 with visible light AR coating formed on both sides and LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 44.8%, and the average transmittance in the UVB region was 2.0%. In the test piece 32U (substrate resin 3 with UVA visible light AR coating formed on both sides and LA-52 (0.2 wt%) added), the average transmittance in the UVA region was 48.6%, and the average transmittance in the UVB region was 2.9%.

In addition, in the sample 33 (substrate resin 3 to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added), the average transmittance in the UVA region is 42.0%, and the average transmittance in the UVB region is 2.1%. In the sample 33A (substrate resin 3 with visible light AR coating formed on both sides and LA-52 (0.2 wt%) and LA-46 (0.001 wt%) added), the average transmittance in the UVA region is 40.5%, and the average transmittance in the UVB region is 1.6%. In the test piece 33U (substrate resin 3 with UVA visible light AR coating formed on both sides and added with LA-52 (0.2 wt%) and LA-46 (0.001 wt%)), the average transmittance in the UVA region was 43.4%, and the average transmittance in the UVB region was 2.2%.

In the results shown in FIG. 12D , in the test piece 34 (substrate resin 3 with LA-46 (0.003 wt%) added), the average transmittance in the UVA region was 31.8%, and the average transmittance in the UVB region was 0.7%. In the test piece 34A (substrate resin 3 with visible light AR coating formed on both sides and LA-46 (0.003 wt%) added), the average transmittance in the UVA region was 29.3%, and the average transmittance in the UVB region was 0.7%. In the test piece 34U (substrate resin 3 with UVA visible light AR coating formed on both sides and LA-46 (0.003 wt%) added), the average transmittance in the UVA region was 32.5%, and the average transmittance in the UVB region was 0.7%.

In addition, in the test piece 35 (substrate resin 3 with LA-46 (0.005 wt%) added), the average transmittance in the UVA region was 26.5%, and the average transmittance in the UVB region was 0.6%. In the test piece 35A (substrate resin 3 with visible light AR coating formed on both sides and LA-46 (0.005 wt%) added), the average transmittance in the UVA region was 24.2%, and the average transmittance in the UVB region was 0.5%. In the test piece 35U (substrate resin 3 with UVA visible light AR coating formed on both sides and LA-46 (0.005 wt%) added), the average transmittance in the UVA region was 26.8%, and the average transmittance in the UVB region was 0.5%.

According to the results shown in FIG. 12C and D, by adding a free radical scavenger and/or an ultraviolet absorber to the base resin 3, the transmittance in the UVA region can be made 25% or more, and the transmittance in the UVB region can be made 3% or less. When the transmittance in the UVB region is reduced, the transmittance in the UVB region can be made 1% or less by adding an ultraviolet absorber to the base resin 3 (for example, refer to test pieces 34 and 35 in FIG. 12D ). In addition, when it is desired to reduce the transmittance in the UVB region as much as possible while increasing the transmittance in the UVA region, by using test pieces 32 and 33, the transmittance in the UVA region can be made 40% or more, and the transmittance in the UVB region can be made 3% or less. Furthermore, when UVA visible light AR coating is formed on both sides, compared with the case where only a radical scavenger and/or an ultraviolet absorber is added to the base resin 3, the transmittance in the UVB region can be suppressed to the same level of less than about 3%, while the transmittance in the UVA region can be improved.

According to the example shown in FIG. 12 , the following ophthalmic lens can be formed: the total UVA average transmittance of each substrate resin and the coating layer constituting the substrate layer of the ophthalmic lens is higher than the UVA average transmittance of the substrate layer, and the total UVB average transmittance of the substrate layer and the coating layer is lower than the UVB average transmittance of the substrate layer (for example, refer to FIGS. 12A to 12D ). In this way, an ophthalmic lens that does not transmit the UVB region as much as possible and transmits the UVA region as much as possible can be formed. Furthermore, the UVA average transmittance indicates the average transmittance of the UVA region, and the UVB average transmittance indicates the average transmittance of the UVB region.

In addition, the coating layer of the eyeglass lens may include an anti-reflection layer that prevents reflection of wavelengths in the UVA region and the visible light region. In the above, the anti-reflection layer is referred to as a UVA visible light AR coating. According to the UVA visible light AR coating, the wavelengths in the UVB region can be reflected as much as possible without allowing the wavelengths in the UVB region to pass through the eyeglass lens (for example, refer to FIG. 11).

In addition, the coating layer may have a characteristic that the reflectivity increases as the wavelength becomes shorter in the wavelength region above 280 nm and below 315 nm. As shown in Figures 3, 5, 9 to 11, the reflectivity of the UVA visible light AR coating increases as the wavelength becomes shorter in the region of 280 nm to 315 nm, thereby further cutting off the wavelength of the UVB region.

The substrate layer may contain a free radical scavenger and/or an ultraviolet absorber. For example, it is obvious that by adding a free radical scavenger or an ultraviolet absorber to the resin 2, the wavelength of the UVB region is prevented from passing as much as possible, and the wavelength of the UVA region is allowed to pass as much as possible. Furthermore, the substrate layer may contain a free radical scavenger and/or an ultraviolet absorber, and the coating layer may include an anti-reflection film layer that prevents reflection of wavelengths in the UVA region and the visible light region.

Furthermore, the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and the coating layer may be greater than the difference between the UVA average transmittance and the UVB average transmittance of the substrate layer alone, or the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and the anti-reflection film layer for preventing reflection of a specific wavelength in the visible light region (see, for example, FIGS. 12A to 12D ). Thus, for example, compared to an existing lens having a visible light AR coating formed thereon, wavelengths in the UVB region can be prevented from being transmitted as much as possible, and wavelengths in the UVA region can be transmitted as much as possible.

In addition, the ophthalmic lens of the present invention may include a substrate layer and a coating layer, and the total UVA average transmittance of the substrate layer and the coating layer is substantially the same as or higher than the UVA average transmittance of the substrate layer, and the total UVB average transmittance of the substrate layer and the coating layer is substantially the same as or lower than the UVB average transmittance of the substrate layer. Furthermore, the ophthalmic lens may be used as long as the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and the coating layer is greater than the difference between the UVA average transmittance and the UVB average transmittance of the substrate layer alone, or the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and the anti-reflection coating layer that prevents reflection of a specific wavelength in the visible light region. Thus, even if the average transmittance in the UVB region is the same as or slightly higher than the average transmittance of the substrate resin alone, depending on the type of substrate resin, the presence or absence of a free radical scavenger/ultraviolet absorber, and the combination of the UVA visible light AR coating, an eyeglass lens can be constructed that cuts off the wavelength of the UVB region as much as possible and transmits the wavelength of the UVA region as much as possible.

FIG13 is a table showing a comparison of the solar ultraviolet transmittance of each substrate resin in each wavelength region (corresponding wavelength). The solar ultraviolet transmittance includes the transmittance τ _SUVA (Formula 1) of the solar ultraviolet A region and the transmittance τ _SUVB (Formula 2) of the solar ultraviolet B region defined in JIS T7333:2018 (ISO8980-3:2013). [Formula 1] [Number 2] E _S (λ): Solar radiation distribution S (λ): Relative spectral effective function relative to UV radiation

In the table shown in FIG. 13A , the transmittance τ _SUVA (Formula 1) in the solar ultraviolet A region and the transmittance τ _SUVB in the solar ultraviolet B region are compared for samples 11 to 16.

In the results shown in FIG. 13A , in the sample 11 (resin 1 for substrate only), the transmittance τ _SUVB is 85.7%, and the transmittance τ _SUVA is 89.8%. In the sample 12 (resin 1 for substrate with visible light AR coating formed), the transmittance τ _SUVB is 65.0%, and the transmittance τ _SUVA is 76.4%. In the sample 13 (resin 1 for substrate with UVA visible light AR coating formed), the transmittance τ _SUVB is 78.7%, and the transmittance τ _SUVA is 89.7%.

In addition, in the sample 14 (resin 1 for substrate with LA-63P (0.2 wt%) added), the transmittance τ _SUVB was 80.9%, and the transmittance τ _SUVA was 85.7%. In the sample 15 (resin 1 for substrate with visible light AR coating formed on both sides and LA-63P (0.2 wt%) added), the transmittance τ _SUVB was 59.5%, and the transmittance τ _SUVA was 74.0%. In the sample 16 (resin 1 for substrate with UVA visible light AR coating formed on both sides and LA-63P (0.2 wt%) added), the transmittance τ _SUVB was 72.3%, and the transmittance τ _SUVA was 85.2%.

In the results shown in FIG. 13B , in the sample 21 (substrate resin 2 only), the transmittance τ _SUVB is 58.9%, and the transmittance τ _SUVA is 77.2%. In the sample 22 (substrate resin 2 with visible light AR coating formed), the transmittance τ _SUVB is 46.6%, and the transmittance τ _SUVA is 68.7%. In the sample 23 (substrate resin 2 with UVA visible light AR coating formed), the transmittance τ _SUVB is 55.0%, and the transmittance τ _SUVA is 77.9%.

In addition, in the sample 24 (substrate resin 2 to which LA-52 (0.2 wt%) was added), the transmittance τ _SUVB was 20.7%, and the transmittance τ _SUVA was 55.2%. In the sample 25 (substrate resin 2 to which LA-52 (0.2 wt%) was added and formed with a visible light AR coating on both sides), the transmittance τ _SUVB was 16.4%, and the transmittance τ _SUVA was 51.7%. In the sample 26 (substrate resin 2 to which LA-52 (0.2 wt%) was added and formed with a UVA visible light AR coating on both sides), the transmittance τ _SUVB was 21.7%, and the transmittance τ _SUVA was 56.9%.

In addition, in the sample 27 (substrate resin 2 with LA-57 (0.2 wt%) added), the transmittance τ _SUVB was 10.1%, and the transmittance τ _SUVA was 47.7%. In the sample 28 (substrate resin 2 with visible light AR coating formed on both sides and LA-57 (0.2 wt%) added), the transmittance τ _SUVB was 8.4%, and the transmittance τ _SUVA was 45.2%. In the sample 29 (substrate resin 2 with UVA visible light AR coating formed on both sides and LA-57 (0.2 wt%) added), the transmittance τ _SUVB was 10.8%, and the transmittance τ _SUVA was 48.9%.

In the results shown in FIG. 13C , in the test piece 31 (substrate resin 3 only), the transmittance τ _SUVB is 11.8%, and the transmittance τ _SUVA is 47.3%. In the test piece 31A (substrate resin 3 with visible light AR coating formed), the transmittance τ _SUVB is 10.6%, and the transmittance τ _SUVA is 43.4%. In the test piece 31U (substrate resin 3 with UVA visible light AR coating formed), the transmittance τ _SUVB is 11.2%, and the transmittance τ _SUVA is 47.9%.

In the test piece 32 (substrate resin 3 to which LA-52 (0.2 wt%) was added), the transmittance τ _SUVB was 4.3%, and the transmittance τ _SUVA was 37.5%. In the test piece 32A (substrate resin 3 to which LA-52 (0.2 wt%) was added and formed with a visible light AR coating on both sides), the transmittance τ _SUVB was 3.1%, and the transmittance τ _SUVA was 34.9%. In the test piece 32U (substrate resin 3 to which LA-52 (0.2 wt%) was added and formed with a UVA visible light AR coating on both sides), the transmittance τ _SUVB was 4.5%, and the transmittance τ _SUVA was 38.4%.

In the test piece 33 (substrate resin 3 to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added), the transmittance τ _SUVB is 3.2%, and the transmittance τ _SUVA is 32.8%. In the test piece 33A (substrate resin 3 to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added with visible light AR coating on both sides), the transmittance τ _SUVB is 2.5%, and the transmittance τ _SUVA is 31.3%. In the test piece 33U (substrate resin 3 having UVA visible light AR coating formed on both surfaces and added with LA-52 (0.2 wt%) and LA-46 (0.001 wt%)), the transmittance τ _SUVB was 3.5%, and the transmittance τ _SUVA was 33.9%.

In the results shown in FIG. 13D , in the test piece 34 (substrate resin 3 to which LA-46 (0.003 wt%) was added), the transmittance τ _SUVB was 1.1%, and the transmittance τ _SUVA was 23.9%. In the test piece 34A (substrate resin 3 to which LA-46 (0.003 wt%) was added and formed with a visible light AR coating on both sides), the transmittance τ _SUVB was 1.0%, and the transmittance τ _SUVA was 21.9%. In the test piece 34U (substrate resin 3 to which LA-46 (0.003 wt%) was added and formed with a UVA visible light AR coating on both sides), the transmittance τ _SUVB was 1.1%, and the transmittance τ _SUVA was 24.5%.

In the test piece 35 (substrate resin 3 to which LA-46 (0.005 wt%) was added), the transmittance τ _SUVB was 1.0%, and the transmittance τ _SUVA was 19.7%. In the test piece 35A (substrate resin 3 to which LA-46 (0.005 wt%) was added and a visible light AR coating was formed on both sides), the transmittance τ _SUVB was 0.9%, and the transmittance τ _SUVA was 17.9%. In the test piece 35U (substrate resin 3 to which LA-46 (0.005 wt%) was added and a UVA visible light AR coating was formed on both sides), the transmittance τ _SUVB was 0.9%, and the transmittance τ _SUVA was 19.9%.

FIG14 is a diagram showing a table comparing the visual transmittance of each test piece. The visual transmittance is calculated using Formula 3 defined in JIS T7333:2018 (ISO8980-3:2013). [Formula 3] Here, τ(λ): spectral transmittance of eyeglass lens V(λ): spectral sensitivity function of sunlight S _D65 (λ): spectral radiation distribution of CIE standard light source D56

In the results shown in FIG. 14A , in sample 11 (resin 1 for substrate only), the visual transmittance is 92.5%, in sample 12 (resin 1 for substrate with visible light AR coating formed), the visual transmittance is 98.9%, and in sample 13 (resin 1 for substrate with UVA visible light AR coating formed), the visual transmittance is 97.4%.

In addition, in the sample 14 (resin 1 for substrate to which LA-63P (0.2 wt%) was added), the visual transmittance was 92.0%, in the sample 15 (resin 1 for substrate to which LA-63P (0.2 wt%) was added and formed with visible light AR coating on both sides), the visual transmittance was 98.4%, and in the sample 16 (resin 1 for substrate to which LA-63P (0.2 wt%) was added and formed with UVA visible light AR coating on both sides), the visual transmittance was 97.0%.

In addition, in the sample 21 (resin 2 for base material only), the visual transmittance is 91.4%, in the sample 22 (resin 2 for base material with visible light AR coating formed), the visual transmittance is 98.9%, and in the sample 23 (resin 2 for base material with UVA visible light AR coating formed), the visual transmittance is 97.0%.

In addition, in the sample 24 (substrate resin 2 to which LA-52 (0.2 wt%) was added), the visual transmittance was 91.0%, in the sample 25 (substrate resin 2 to which LA-52 (0.2 wt%) was added and formed with a visible light AR coating on both sides), the visual transmittance was 98.5%, and in the sample 26 (substrate resin 2 to which LA-52 (0.2 wt%) was added and formed with a UVA visible light AR coating on both sides), the visual transmittance was 96.7%.

In addition, in the sample 27 (substrate resin 2 to which LA-57 (0.2 wt%) was added), the visual transmittance was 90.9%, in the sample 28 (substrate resin 2 to which LA-57 (0.2 wt%) was added and formed on both sides with visible light AR coating), the visual transmittance was 98.4%, and in the sample 29 (substrate resin 2 to which LA-57 (0.2 wt%) was added and formed on both sides with UVA visible light AR coating), the visual transmittance was 96.6%.

In the results shown in Figure 14B, in the sample 31 (resin 3 for substrate only), the visual transmittance is 91.9%, in the sample 31A (resin 3 for substrate with visible light AR coating formed), the visual transmittance is 98.4%, and in the sample 31U (resin 3 for substrate with UVA visible light AR coating formed), the visual transmittance is 97.4%.

In addition, in the test piece 32 (resin 3 for substrate to which LA-52 (0.2 wt%) is added), the visual transmittance is 91.3%, in the test piece 32A (resin 3 for substrate to which LA-52 (0.2 wt%) is added and formed with a visible light AR coating on both sides), the visual transmittance is 98.1%, and in the test piece 32U (resin 3 for substrate to which LA-52 (0.2 wt%) is added and formed with a UVA visible light AR coating on both sides), the visual transmittance is 96.6%.

In addition, in the test piece 33 (resin 3 for substrate to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added), the visual transmittance is 91.3%, in the test piece 33A (resin 3 for substrate to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added and a visible light AR coating is formed on both sides), the visual transmittance is 98.3%, and in the test piece 33U (resin 3 for substrate to which LA-52 (0.2 wt%) and LA-46 (0.001 wt%) are added and a UVA visible light AR coating is formed on both sides), the visual transmittance is 96.9%.

In addition, in the test piece 34 (resin 3 for substrate to which LA-46 (0.003 wt%) was added), the visual transmittance was 91.3%, in the test piece 34A (resin 3 for substrate to which LA-46 (0.003 wt%) was added and formed on both sides with visible light AR coating), the visual transmittance was 97.6%, and in the test piece 34U (resin 3 for substrate to which LA-46 (0.003 wt%) was added and formed on both sides with UVA visible light AR coating), the visual transmittance was 96.5%.

In addition, in the test piece 35 (resin 3 for substrate to which LA-46 (0.005 wt%) was added), the visual transmittance was 91.6%, in the test piece 35A (resin 3 for substrate to which LA-46 (0.005 wt%) was added and formed on both sides with visible light AR coating), the visual transmittance was 98.0%, and in the test piece 35U (resin 3 for substrate to which LA-46 (0.005 wt%) was added and formed on both sides with UVA visible light AR coating), the visual transmittance was 96.7%.

As shown above, according to Figures 13 and 14, an ophthalmic lens having a transmittance τ _SUVB of less than 5% relative to the visual transmittance in the solar ultraviolet B region can be constructed. This condition is defined as a condition for refractive ophthalmic lenses in JIS T7333:2018 (ISO8980-3:2013). For example, the test pieces 32 to 35 having UVA visible light AR coating formed on both sides can meet the JIS conditions, and by manufacturing an ophthalmic lens processed in the same manner as the above, a refractive ophthalmic lens that is as close to the naked eye state as possible and meets the JIS standard can be constructed.

In the embodiment, the substrate layer or coating layer can be made of any of the above raw materials and materials applicable to the present invention. For example, a fluorine compound resin with a high transmittance, such as HMX10 of Daikin Industries, can also be used as the substrate.

In addition, as an example, the ophthalmic lens of the present invention can also be put into practical use as a non-vision correction lens. For example, it can be used as a smart eyeglass with a pollen protection function for users with normal vision who have hay fever and do not need vision correction, or a smart eyeglass with a moisturizing function for users with normal vision who have dry eyes.

Although the present invention is described above using various embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. Practitioners can know that various changes or improvements can be made to the above embodiments. According to the description of the patent application scope, the form in which such changes or improvements are made can also be included in the technical scope of the present invention.

FIG. 1 is a graph showing the light transmittance of each ophthalmic lens of the prior art. FIG. 2 is a graph showing an example of the total transmittance of each substrate layer and each AR coating layer based on substrate resin 1. FIG. 3 is a graph showing an example of the reflectance of test pieces 11 to 16. FIG. 4 is a graph showing an example of the total transmittance of each substrate layer and each AR coating layer based on substrate resin 2. FIG. 5 is a graph showing an example of the reflectance of test pieces 21 to 29. FIG. 6 is a graph showing an example of the transmittance of each substrate layer based on substrate resin 3 to which an ultraviolet absorber (LA-46) and/or a radical scavenger (LA-52) is added. FIG. 7 is a diagram showing an example of transmittance when a UVA visible light AR coating is formed on each substrate layer shown in FIG. 6. FIG. 8 is a diagram showing a comparative example of transmittance of a test piece 31 formed with each AR coating. FIG. 9 is a diagram showing a comparative example of reflectance of a test piece 31 formed with each AR coating. FIG. 10 is a diagram showing a comparative example of reflectance of a test piece 32 and a test piece 35 formed with each AR coating. FIG. 11 is a diagram showing a comparative example of reflectance of each test piece formed with a UVA visible light AR coating. FIG. 12A is a diagram showing a table comparing transmittances of each substrate resin in each wavelength region. FIG. 12B is a diagram showing a table comparing the transmittance of each substrate resin in each wavelength region. FIG. 12C is a diagram showing a table comparing the transmittance of each substrate resin in each wavelength region. FIG. 12D is a diagram showing a table comparing the transmittance of each substrate resin in each wavelength region. FIG. 13A is a diagram showing a table comparing the solar ultraviolet transmittance of each substrate resin in each wavelength region. FIG. 13B is a diagram showing a table comparing the solar ultraviolet transmittance of each substrate resin in each wavelength region. FIG. 13C is a diagram showing a table comparing the solar ultraviolet transmittance of each substrate resin in each wavelength region. FIG. 13D is a diagram showing a table comparing the solar ultraviolet transmittance of each substrate resin in each wavelength region. FIG. 14A is a diagram showing a table comparing the visual transmittance of each test piece. FIG. 14B is a diagram showing a table comparing the visual transmittance of each test piece.

Claims (9)

A lens for eyeglasses, comprising a substrate layer and a coating layer, wherein the combined UVA average transmittance of the substrate layer and the coating layer is higher than the UVA average transmittance of the substrate layer, and the combined UVB average transmittance of the substrate layer and the coating layer is lower than the UVB average transmittance of the substrate layer. The ophthalmic lens of claim 1, wherein the coating layer comprises an anti-reflection film layer for preventing reflection of wavelengths in the UVA region and the visible light region. The ophthalmic lens of claim 1, wherein the substrate layer comprises a free radical scavenger and/or an ultraviolet absorber. As in claim 1, the above-mentioned base material layer contains a free radical scavenger and/or an ultraviolet absorber, and the above-mentioned coating layer contains an anti-reflective film layer that prevents reflection of wavelengths in the UVA region and the visible light region. An ophthalmic lens as claimed in any one of claims 1 to 4, wherein the transmittance τ _SUVB of the solar ultraviolet B region of the ophthalmic lens is less than 5% relative to the visual transmittance. The ophthalmic lens according to any one of claims 1 to 4, wherein the combined UVB average reflectivity of the substrate layer and the coating layer is higher than the UVB average reflectivity of the substrate layer. The ophthalmic lens according to any one of claims 1 to 4, wherein the coating layer has a characteristic that the reflectivity increases as the wavelength becomes shorter in the wavelength region of 280 nm or more and less than 315 nm. An ophthalmic lens as claimed in any one of claims 1 to 4, wherein the difference between the total UVA average transmittance and the UVB average transmittance of the above-mentioned substrate layer and the above-mentioned coating layer is greater than the difference between the UVA average transmittance and the UVB average transmittance of the above-mentioned substrate layer alone, or the difference between the total UVA average transmittance and the UVB average transmittance of the above-mentioned substrate layer and the anti-reflection film layer that prevents reflection of a specific wavelength in the visible light region. A lens for eyeglasses, which has a substrate layer and a coating layer, and the total UVA average transmittance of the substrate layer and the coating layer is approximately the same as or higher than the UVA average transmittance of the substrate layer, the total UVB average transmittance of the substrate layer and the coating layer is approximately the same as or lower than the UVB average transmittance of the substrate layer, the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and the coating layer is greater than the difference between the UVA average transmittance and the UVB average transmittance of the substrate layer alone, or the difference between the total UVA average transmittance and the UVB average transmittance of the substrate layer and an anti-reflection film layer for preventing reflection of a specific wavelength in the visible light region.