Plastic optical articles and plastic ophthalmic lenses

Abstract

The plastic optical article 1 is an article in which optical multilayer films 6 are formed on both sides of a plastic base material 2 via intermediate films 4. Each optical multilayer film 6 has a total of 8 layers of SiO2 layers 10 composed of SiO2 and ZrO2 layers 12 composed of ZrO2, and the layer closest to the base material 2 is a ZrO2 layer. Furthermore, the physical film thickness of the optical multilayer film 6 is 480 nm or more and 530 nm or less, the total physical film thickness of all the SiO2 layers 10 is 350 nm or more and 440 nm or less, and the physical film thickness of the ZrO2 layer 12 that is the first layer L1 closest to the base material 2 is 5 nm or more and 12 nm or less.

Description

Technical Field

[0001] This invention relates to plastic optical articles and plastic eyeglass lenses, which are optical articles having a plastic substrate. Background Technology

[0002] As a plastic optical component, the component described in Japanese Patent No. 5248516 (Patent Document 1) is known.

[0003] In this optical component, an optical multilayer film serving as an anti-reflective coating is formed on the surface of a substrate. This optical multilayer film is formed by alternately stacking eight layers of low-refractive-index and high-refractive-index layers, with a high-refractive-index layer as the first layer closest to the substrate. From the viewpoint of ensuring processing stability and generally satisfactory appearance, the reflectivity distribution is W-shaped, with the central peak maxima located near a wavelength of 520 nm. When a plastic lens with such an anti-reflective coating is observed from the incident side, a light green reflected light (a greenish-toned reflective color) is observed.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 5248516 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] The reflected light in this plastic lens is green.

[0009] Green is the color that the human eye perceives most strongly in terms of brightness. That is, green is close to the maximum point of the specific sensitivity curve (wavelength 555nm), which represents the intensity of light intensity perceived by the human eye at each wavelength relative to the maximum sensitivity.

[0010] Therefore, although the reflected light from the aforementioned plastic lens is weak due to its low reflectivity, it becomes noticeable because it is green. In other words, the aforementioned plastic lens has a higher reflectivity than visual sensitivity.

[0011] Especially when the aforementioned plastic lenses are used as eyeglass lenses, the reflected light from the wearer becomes more noticeable to third parties.

[0012] The main objective of this invention is to provide plastic optical products and plastic eyeglass lenses that exhibit less noticeable reflected light.

[0013] Methods for solving problems

[0014] To achieve the above objectives, the invention of technical solution 1 is a plastic optical article in which an optical multilayer film is formed directly or through an intermediate film on at least one side of a plastic substrate. The invention is characterized in that the optical multilayer film alternately comprises a total of eight layers of SiO2 composed of SiO2 and ZrO2 composed of ZrO2, with the layer closest to the substrate being the ZrO2 layer. The physical film thickness of the optical multilayer film is 480 nm to 530 nm, the total physical film thickness of all the SiO2 layers is 350 nm to 440 nm, and the physical film thickness of the ZrO2 layer closest to the substrate is 5 nm to 12 nm.

[0015] The invention of technical solution 2 is as described above, characterized in that the physical film thickness of the ZrO2 layer disposed on the third layer from the substrate side is 11 nm or more and 20 nm or less.

[0016] The invention of technical solution 3 is as described above, characterized in that the physical film thickness of the SiO2 layer disposed on the fourth layer from the substrate side is more than 200 nm and less than 245 nm.

[0017] The invention of technical solution 4 is as described above, characterized in that the sum of the physical film thicknesses from the ZrO2 layer, which is the layer closest to the substrate, to the SiO2 layer disposed as the fourth layer from the substrate side, is 270 nm or more and 330 nm or less.

[0018] The invention of technical solution 5 is as described above, characterized in that the intermediate film is a hard coating film.

[0019] The invention of technical solution 6 is as described above, characterized in that the visual reflectance of the surface on which the optical multilayer film is formed is less than 0.8%.

[0020] The invention of technical solution 7 is as described above, characterized in that the reflected light in the surface on which the optical multilayer film is formed is white or bluish-white.

[0021] To achieve the above objectives, the invention of technical solution 8 is a plastic eyeglass lens, characterized in that it uses the plastic optical product of the above invention.

[0022] Invention Effects

[0023] The main advantage of this invention is that it provides plastic optical products and plastic eyeglass lenses that exhibit less noticeable reflected light. Attached Figure Description

[0024] Figure 1 This is a schematic cross-sectional view of the plastic optical article of the present invention.

[0025] Figure 2It is a graph showing the distribution of spectral reflectance in the visible light region and adjacent region in Examples 1 to 4.

[0026] Figure 3 It is a graph showing the distribution of spectral reflectance in the visible light region and adjacent region in Examples 5 to 8.

[0027] Figure 4 The graph shows the distribution of spectral reflectance in the visible light region and adjacent region of Comparative Examples 1 to 4.

[0028] Figure 5 It is a CIE chromaticity diagram depicting the chromaticity of Examples 1 to 8.

[0029] Figure 6 It is a CIE chromaticity diagram depicting the chromaticity of Comparative Examples 1 to 4. Detailed Implementation

[0030] Hereinafter, examples of embodiments of the present invention will be described.

[0031] This invention is not limited to the following methods.

[0032] like Figure 1 As shown, the plastic optical article 1 of the present invention comprises: a plate-shaped substrate 2, an optical multilayer film 6 formed on both sides (each film-forming surface M) with an intermediate film 4 in between, and a surface film 8 formed on each optical multilayer film 6 (on the side opposite to the substrate 2, the air side).

[0033] Each intermediate film 4, each optical multilayer film 6, and each surface film 8 have the same structure when viewed from the substrate 2.

[0034] Alternatively, the substrate 2 can be a shape other than a block or plate. Each film-forming surface M can be planar, curved, or have a different shape for each film-forming surface M. Furthermore, at least one of the intermediate films 4 and the surface films 8 can be omitted. Moreover, at least one of the intermediate films 4, the optical multilayer films 6, and the surface films 8 can have different structures when viewed from the substrate 2 on each film-forming surface M. Additionally, at least one of the intermediate films 4, the optical multilayer films 6, and the surface films 8 can be formed only on one side of the substrate 2.

[0035] As the material for substrate 2, plastic is used, preferably a thermosetting resin, such as polyurethane resin, thiopolyurethane resin, cyclosulfide resin, polycarbonate resin, polyester resin, acrylic resin, polyethersulfone resin, poly4-methylpentene-1 resin, diethylene glycol dielyl carbonate resin, or combinations thereof. Furthermore, as a preferred material for substrate 2 with a high refractive index, a polyurethane resin obtained by addition polymerization of a polyisocyanate compound with at least one of a polythiol and a sulfur-containing polyol is used. Moreover, as a preferred material for substrate 2 with a high refractive index, a cyclosulfide resin obtained by addition polymerization of a cyclosulfide group with at least one of a polythiol and a sulfur-containing polyol is used.

[0036] Substrate 2 preferably contains an ultraviolet absorber.

[0037] Each intermediate film 4 is a film disposed between the substrate 2 and the optical multilayer film 6, such as a hard coating film. It should be noted that at least one of the intermediate films 4 can be a film other than the hard coating film instead of the hard coating film, or a film other than the hard coating film can be added to at least one of the substrate 2 side and the air side of the hard coating film.

[0038] The hard coating is preferably formed by uniformly applying a hard coating liquid to the surface of the substrate 2.

[0039] Furthermore, as a material for hard coating films, organosiloxane resins containing inorganic oxide particles are preferably used. The hard coating solution is preferably prepared by dispersing (mixing) a solute whose main components are organosiloxane resin and inorganic oxide particle sol in an aqueous or alcohol-based solvent. The organosiloxane resin is preferably obtained by hydrolytic condensation of alkoxysilanes. Specific examples of organosiloxane resins include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, methyltrimethoxysilane, ethyl silicate, or combinations thereof. These hydrolytic condensates of alkoxysilanes can be manufactured by hydrolyzing the alkoxysilane compound or combinations thereof in an acidic aqueous solution such as hydrochloric acid.

[0040] On the other hand, specific examples of inorganic oxide particles can be substances formed by crystallizing individual or any two or more of the sols of zinc oxide, silicon dioxide (silicon dioxide particles), aluminum oxide, titanium dioxide (titanium dioxide particles), zirconium oxide (zirconia particles), tin oxide, beryllium oxide, antimony oxide, tungsten oxide, and cerium oxide. From the viewpoint of ensuring the transparency of the hard coating film, the diameter of the inorganic oxide particles is preferably 1 nm to 100 nm, more preferably 1 nm to 50 nm. In addition, from the viewpoint of ensuring at least one of the hardness and toughness of the hard coating film, the mixing amount (concentration) of the inorganic oxide particles is preferably 40 wt% to 60 wt% of the total components of the hard coating film. Furthermore, at least one of acetylacetone metal salt and ethylenediaminetetraacetic acid metal salt may be added as a curing catalyst to the hard coating liquid. Moreover, surfactants, colorants, solvents, etc., may be added to the hard coating liquid according to the needs of ensuring adhesion to the substrate 2 and facilitating formation.

[0041] The physical film thickness of the hard coating is preferably 0.5 μm to 4.0 μm, more preferably 1.0 μm to 3.0 μm. The lower limit of this film thickness range is determined from the perspective that it is difficult to obtain sufficient hardness when the film is thinner. On the other hand, the upper limit is determined from the perspective that the possibility of property-related problems such as cracking or brittleness occurring is significantly increased when the film is thicker.

[0042] Furthermore, as the intermediate film 4, from the viewpoint of improving the adhesion of the hard coating film, a primer film can also be applied between the hard coating film and the surface of the substrate 2. Examples of materials for the primer film include polyurethane resins, acrylic resins, methacrylic resins, silicone resins, or combinations thereof. The primer film is preferably formed by uniformly applying a primer liquid to the surface of the substrate 2. The primer liquid is preferably a liquid formed by mixing the aforementioned resin materials and inorganic oxide particles in water or an alcohol-based solvent.

[0043] Each optical multilayer film 6 of the plastic optical article 1 is formed on the intermediate film 4. Alternatively, if the intermediate film 4 is omitted, the optical multilayer film 6 is formed on the substrate 2 (each film-forming surface M).

[0044] Each optical multilayer film 6 is formed to perform optical functions, such as anti-reflective film, reflective film, semi-reflective film, ND filter, and bandpass filter. The functions of each optical multilayer film 6 can also be different.

[0045] Each optical multilayer film 6 is formed, for example, by vacuum evaporation or sputtering. From the viewpoint of ensuring ease of manufacturing, it is preferable that the fabrication methods of each optical multilayer film 6 are the same. Alternatively, the fabrication methods of each optical multilayer film 6 may also be different.

[0046] Each optical multilayer film 6 is formed by alternately stacking a low-refractive-index layer made of a low-refractive-index material as a metal oxide and a high-refractive-index layer made of a high-refractive-index material as a metal oxide.

[0047] In the plastic optical product 1, each optical multilayer film 6 has an overall structure of 8 layers. Furthermore, in each optical multilayer film 6, if the layer closest to the substrate 2 is designated as the first layer L1, then the odd-numbered layers are high-refractive-index layers and the even-numbered layers are low-refractive-index layers.

[0048] The low refractive index material is silicon oxide (SiO2). Therefore, the even-numbered layers of each optical multilayer film 6 become SiO2 layers 10. Alternatively, the low refractive index material may be a mixture of two or more of calcium fluoride (CaF2), magnesium fluoride (MgF2), or SiO2.

[0049] Furthermore, the high refractive index material is zirconium oxide (ZrO2). Thus, the odd-numbered layers of each optical multilayer film 6 become ZrO2 layers 12. Alternatively, the high refractive index material may also be a mixture of two or more of the following: titanium oxide (TiO2), tantalum oxide (Ta2O5), niobium oxide (Nb2O5), hafnium oxide (HfO2), selenium oxide (CeO2), aluminum oxide (Al2O3), yttrium oxide (YO2), or ZrO2.

[0050] In each optical multilayer film 6, one type of high-refractive-index material and one type of low-refractive-index material are used, so the film design is easy and the film formation cost is low.

[0051] Each layer in the optical multilayer film 6 appropriately possesses the various characteristics shown below.

[0052] That is, in order to make the reflected light less noticeable, starting from the substrate 2 side of each optical multilayer film 6 (the same counting method is used below), the physical film thickness of the SiO2 layer 10 of the fourth layer L4 is more than 200 nm and less than 245 nm.

[0053] In addition, to make the reflected light less noticeable, the physical film thickness of the ZrO2 layer 12 of the third layer L3 is between 11 nm and 20 nm.

[0054] Furthermore, the physical film thickness of the ZrO2 layer 12 in the first layer L1 is between 5 nm and 12 nm. If the physical film thickness is less than 5 nm, it is too thin to ensure the accuracy of the film thickness. If the physical film thickness exceeds 12 nm, the film stress (tensile stress) of the first layer L1 may cause excessive stretching, which is likely to become the main cause of cracks after film formation.

[0055] In addition, in order to make the reflected light less noticeable, the sum of the physical film thicknesses from the first layer L1 (ZrO2 layer 12) to the fourth layer L4 (SiO2 layer 10) is above 270 nm and below 330 nm.

[0056] In addition, to make the reflected light less noticeable, the physical thickness of the optical multilayer film 6 (the sum of the physical thicknesses of the ZrO2 layer 12 from the first layer L1 to the SiO2 layer 10 of the eighth layer L8) is 480 nm to 530 nm, and the total physical thickness of the SiO2 layers 10 (the sum of the physical thicknesses of each SiO2 layer 10 in layers 2, 4, 6, and 8 L2, L4, L6, and L8) is 350 nm to 440 nm.

[0057] Furthermore, regarding each film-forming surface M on which the optical multilayer film 6 is formed directly or indirectly, if the visual sensitivity reflectance of a single surface in a 2° field of view of the D65 light source is less than 0.8%, then by utilizing the low level of visual sensitivity reflectance that has not been discovered to date, a plastic optical article 1 that exhibits extremely inconspicuous reflected light is provided.

[0058] Furthermore, from the viewpoint of making the color of reflected light less noticeable, white (achromatic) and bluish-white are preferred, with white (achromatic) being particularly preferred. The color of reflected light can be qualitatively captured using the xy coordinates (x, y) in the xy color system. The xy coordinates (x, y) are represented by the CIE chromaticity diagram.

[0059] Each surface film 8 is a film disposed on the air side closer to the optical multilayer film 6, for example, a fouling film (waterproof film, oilproof film). In this case, a fouling-resistant function is further imparted to the plastic optical article 1. It should be noted that at least one of the surface films 8 can be formed as a film other than a fouling film instead of a fouling film, or a film other than a fouling film, such as a damage-resistant film, can be added to at least one of the substrate 2 side and the air side of the fouling film.

[0060] Antifouling films, for example, are films formed by the condensation polymerization of organosilicon compounds. Through condensation polymerization, the film can be thickened and densified, resulting in better adhesion and surface hardness to the optical multilayer film 6. It not only exhibits waterproof and oil-proof properties but also provides excellent wiping properties for dirt.

[0061] Antifouling films are formed using known methods such as vapor deposition or ion sputtering.

[0062] The organosilicon compound prior to polycondensation is preferably composed of -SiR y X 3-y(R is a monovalent organic group, X is a hydrolyzable group, and y is an integer from 0 to 2) represents a compound containing a silicon functional group. Here, for example, X can be an alkoxy group such as -OCH3 or -OCH2CH3, an acyloxy group such as -OCOCH3, or -ON=CR. a R b Isoketoxime (R) a R b (representing monovalent organic groups), halogen groups such as -Cl and -Br, and -NR respectively. c R d Isoamino (R) c R d These represent groups such as monovalent organic groups.

[0063] As such organosilicon compounds, fluorinated organosilicon compounds are preferred. Fluorinated organosilicon compounds exhibit excellent overall properties, including water and oil repellency, electrical insulation, mold release properties, solvent resistance, lubricity, heat resistance, and defoaming properties. In particular, organosilicon compounds with relatively large molecular weights (1000–50000) containing perfluoroalkyl or perfluoropolyether groups within their molecules exhibit excellent stain resistance.

[0064] Furthermore, by using the aforementioned plastic optical product 1 as a plastic eyeglass lens, eyeglasses that exhibit subtle, unobtrusive reflections and excellent aesthetics can be produced.

[0065] Next, embodiments 1 to 8 of the present invention and comparative examples 1 to 4, which are not part of the present invention, will be described with appropriate use of the accompanying drawings. It should be noted that the present invention is not limited to the following embodiments. Furthermore, according to the understanding method of the present invention, sometimes embodiments become comparative examples, or comparative examples become embodiments.

[0066] In these embodiments or comparative examples, the substrate 2 is made of thermosetting resin for eyeglasses, and the plastic eyeglass lenses are standard-sized circles.

[0067] Substrate 2 is the same as in the examples and comparative examples, and is a spherical lens with a center thickness of 1.9 mm and a power of S-0.00, made of thiopolyurethane resin with a refractive index of 1.60. Furthermore, substrate 2 is not dyed or otherwise treated, and is itself colorless and transparent.

[0068] In addition, in these embodiments or comparative examples, as the intermediate film 4, a hard coating film formed by coating with a hard coating liquid is applied to both sides.

[0069] A hard coating film in contact with the substrate 2 is formed by applying a hard coating liquid to the substrate 2 and heating it.

[0070] That is, firstly, in a reaction vessel, 206g of methanol, 300g of methanol-dispersed titanium dioxide sol (manufactured by Nichibukai Chemical Co., Ltd., solid content 30%), 60g of γ-epoxypropoxypropyltrimethoxysilane, 30g of γ-epoxypropoxypropylmethyldiethoxysilane, and 60g of tetraethoxysilane are added dropwise. Then, 0.01N (equivalent concentration) hydrochloric acid aqueous solution is added dropwise to the mixture, and the mixture is stirred to carry out hydrolysis.

[0071] Next, 0.5 g of flow modifier and 1.0 g of catalyst were added, and the mixture was stirred at room temperature for 3 hours to form a hard coating solution.

[0072] Then, the hard coating liquid is applied to both sides of the substrate 2 and heated at 120°C for 1.5 hours to form a hard coating film with a thickness of 2.5 μm.

[0073] Furthermore, in Examples 1 to 8 and Comparative Examples 1 to 4, an optical multilayer film 6 and a surface film 8 with the same configuration were formed on both sides of the hard coating.

[0074] The optical multilayer film 6 is an anti-reflective film with a total of 8 layers. It is first formed on the convex side (surface side) of the optical product by vacuum evaporation, and then formed on the concave side (back side) of the optical product.

[0075] The even-numbered SiO2 layer 10 disposed in the optical multilayer film 6 uses SiO2 manufactured by Canon Optron Corporation as the evaporation source and is deposited in a vacuum chamber by conventional evaporation.

[0076] The odd-numbered ZrO2 layers 12, configured in the optical multilayer film 6, are deposited in a vacuum chamber using ZrO2 manufactured by Canon Optron Corporation as the evaporation source via ion-assisted evaporation. The ion-assisted gas is a mixture of argon (Ar) and oxygen (O2), which are rare gases. Ion-assisted evaporation is performed at an accelerating voltage of 500V and an accelerating current of 300mA. The refractive index of each ZrO2 layer 12 is greater than that of SiO2 and can be adjusted according to the film deposition rate, film deposition temperature (vacuum chamber temperature), vacuum level, presence or absence of ion-assisted treatment, the accelerating voltage during ion-assisted evaporation, and the type of gas.

[0077] The surface film 8 is a dirt-resistant film (water- and oil-resistant film), which is formed on the optical multilayer film 6 with a thickness of 5.00 nm using OF-SR manufactured by Canon Optron Corporation.

[0078] The optical multilayer films 6 (first layer L1 to eighth layer L8) and surface films 8 of Examples 1 to 8 and Comparative Examples 1 to 4 were formed as described in the upper parts of Tables 1 to 3 below. It should be noted that the refractive index of each layer is the same as that of a wavelength of 500 nm, which is the same value (1.469) in all SiO2 layers 10 in Examples 1 to 8 and Comparative Examples 1 to 4, the same value (2.106) in all ZrO2 layers 12, and the same value (1.350) in all surface films 8.

[0079] [Table 1]

[0080]

[0081] [Table 2]

[0082]

[0083] [Table 3]

[0084]

[0085] For Examples 1-8 and Comparative Examples 1-4, the spectrophotometric reflectance distribution in the visible light region (wavelength region of 400 nm to 780 nm) and adjacent regions (wavelength region of 380 nm to 400 nm) was measured. Figures 2-4 And the visual reflectance of the convex side (D65 light source, 2° field of view) (the lower part of each of Tables 1 to 3).

[0086] In addition, for Examples 1-8 and Comparative Examples 1-4, chromaticity, i.e., x and y in the xy color system (D65 light source, 2° field of view) was measured (the upper part of the lower section of Tables 1-3). Figure 5 , Figure 6 The diagram shows CIE chromaticity diagrams depicting (x, y) for Examples 1-8 and Comparative Examples 1-4.

[0087] The physical thickness (LT) of the optical multilayer film 6 in Comparative Example 1 (the sum of the physical thicknesses of the first layer L1 to the eighth layer L8) is 542.00 nm, which is higher than 530 nm. The total physical thickness of the SiO2 layers 10 (LS) (the sum of the physical thicknesses of the 2nd, 4th, 6th, and 8th layers L2, L4, L6, and L8) is 462.00 nm, which is higher than 440 nm. In addition, the physical thickness (L4) of the fourth layer L4, the SiO2 layer 10, is 250 nm, which is higher than 245 nm. Furthermore, the physical thickness (L3) of the third layer L3, the ZrO2 layer 12, is 11.50 nm, which falls within the range of 11 nm to 20 nm. In addition, the physical thickness (L1) of the first layer L1, the ZrO2 layer 12, is 6.00 nm, which falls within the range of 5 nm to 12 nm. Furthermore, the sum of the physical film thicknesses (LL) from the first layer L1 (ZrO2 layer 12) to the fourth layer L4 (SiO2 layer 10) is 331.50 nm, which is higher than 330 nm. The visual reflectance of Comparative Example 1 is 0.71%, which is below 0.8%, and is extremely good. However, in Comparative Example 1, the chromaticity (x, y) = (0.30, 0.28), and the reflected light produced by the small reflections appears pink, making the chromaticity noticeable. The spectrophotometric reflectance distribution of Comparative Example 1 is of the WW type, with two maxima (around 455 nm and 585 nm).

[0088] In Comparative Example 2, LT = 512.50 nm, falling within the range of 480 nm to 530 nm; LS = 387.00 nm, falling within the range of 350 nm to 440 nm; L4 = 218.00 nm, falling within the range of 200 nm to 245 nm; L3 = 22.00 nm, exceeding 20 nm; L1 = 15.00 nm, exceeding 12 nm; and LL = 305.50 nm, falling within the range of 270 nm to 330 nm. The visual reflectance of Comparative Example 2 is 0.64%, which is below 0.8%, and is extremely good. However, in Comparative Example 2, the chromaticity (x, y) = (0.27, 0.25), and the reflected light due to minute reflections appears purple, making the chromaticity noticeable. The spectral reflectance distribution of Comparative Example 2 is a WW type with two maxima (around 440nm and 630nm).

[0089] In Comparative Example 3, LT = 446.00 nm, which is below 480 nm, and LS = 345.00 nm, which is below 350 nm. Furthermore, L4 = 202.00 nm, falling within the range of 200 nm to 245 nm. Furthermore, L3 = 9.00 nm, which is below 11 nm. Additionally, L1 = 6.00 nm, falling within the range of 5 nm to 12 nm. Moreover, LL = 245.00 nm, which is below 270 nm. The visual reflectance of Comparative Example 3 is 0.58%, which is below 0.8%, and is extremely good. However, in Comparative Example 3, the chromaticity (x, y) = (0.30, 0.26), and the reflected light produced by the small reflections appears pinkish, making the chromaticity noticeable. The spectrophotometric reflectance distribution of Comparative Example 3 is of the WW type, with two maxima (around 450 nm and 590 nm).

[0090] In Comparative Example 4, LT = 457.50 nm, which is below 480 nm; LS = 353.50 nm, which falls within the range of 350 nm to 440 nm. Furthermore, L4 = 190.00 nm, which is below 200 nm. Moreover, L3 = 10.00 nm, which is below 11 nm. Additionally, L1 = 11.50 nm, which falls within the range of 5 nm to 12 nm. Furthermore, LL = 254.50 nm, which is below 270 nm. The visual reflectance of Comparative Example 4 is 0.76%, which is below 0.8%, and is extremely good. However, in Comparative Example 4, the chromaticity (x, y) = (0.34, 0.34), and the reflected light produced by the small reflections appears yellow, making the chromaticity noticeable. The spectrophotometric reflectance distribution of Comparative Example 4 exhibits a WW-type pattern with two maxima (around 475 nm and 600 nm).

[0091] In contrast, in Examples 1-8, LT falls within the range of 480nm to 530nm, and LS falls within the range of 350nm to 440nm. Furthermore, L4 falls within the range of 200nm to 245nm. Moreover, L3 falls within the range of 11nm to 20nm. Additionally, L1 falls within the range of 5nm to 12nm. Therefore, the optical multilayer film 6 of Examples 1-8 possesses anti-reflective properties, with each visual sensitivity having a reflectance of 0.8% or less—an extremely excellent level. Furthermore, the reflected light produced by the minute reflections has a bluish-white chromaticity, perceived as a light blue, and is not easily noticed. The reflectance distribution exhibits a W-shape with maximum values ​​located in the range of 450nm to 475nm.

[0092] Furthermore, in Examples 1 to 8, L1 all falls within the range of 5 nm to 12 nm. This facilitates the formation of the first L1 layer and ensures sufficient adhesion to the hard coating, thus minimizing the attention drawn to reflected light.

[0093] Examples 1-8 describe plastic eyeglass lenses in which optical multilayer films 6 are formed on both sides of a plastic substrate 2, separated by an intermediate film 4 serving as a hard coating. Each optical multilayer film 6 alternately comprises a total of eight layers of SiO2 (SiO2 layers 10) and ZrO2 (ZrO2 layers 12), with the first layer L1 closest to the substrate 2 being a ZrO2 layer 12. Furthermore, in Examples 1-8, the physical film thickness of the optical multilayer film 6 is 480 nm to 530 nm, the total physical film thickness of all SiO2 layers 10 is 350 nm to 440 nm, and the physical film thickness of the ZrO2 layer 12 closest to the substrate 2 is 5 nm to 12 nm. Therefore, reflected light is less noticeable, and the optical multilayer film 6 is more easily formed, thereby ensuring excellent adhesion to the intermediate film 4.

[0094] Furthermore, in Examples 1-8, the physical film thickness of the ZrO2 layer 12 disposed as the third layer L3 from the substrate 2 side is 11 nm to 20 nm. Therefore, reflected light is less likely to attract attention.

[0095] Furthermore, in Examples 1-8, the physical film thickness of the SiO2 layer 10 disposed on the fourth layer L4 from the substrate 2 side is 200 nm to 245 nm. As a result, reflected light is even less likely to attract attention.

[0096] Furthermore, the sum of the physical film thicknesses from the first layer L1 (ZrO2 layer 12) to the fourth layer L4 (SiO2 layer 10) is between 270 nm and 330 nm. Therefore, the reflected light is less likely to attract attention.

[0097] In addition, the intermediate film 4 is a hard coating. As a result, the plastic optical product 1 has good hardness and thus good durability.

[0098] Furthermore, in Examples 1-8, the visual reflectance of the convex surface on which the optical multilayer film 6 is formed is 0.8% or less. Therefore, the visual reflectance is extremely low, making the reflected light less noticeable. Additionally, in Examples 1-8, the reflected light from the surface on which the optical multilayer film 6 is formed is white or bluish-white. Therefore, the reflected light is even less noticeable.

Claims

1. A plastic optical article, characterized in that an optical multilayer film is formed directly or through an interlayer film on at least one side of a plastic substrate, wherein, The optical multilayer film is provided with a total of 8 alternating SiO2 layers and ZrO2 layers, with the layer closest to the substrate being the ZrO2 layer. The physical thickness of the optical multilayer film is above 499.5 nm and below 530 nm. The total physical film thickness of all the SiO2 layers is between 350 nm and 440 nm. The physical film thickness of the ZrO2 layer, which is the layer closest to the substrate, is 5 nm to 12 nm. The reflected light from the surface on which the optical multilayer film is formed is white or bluish-white.

2. The plastic optical product according to claim 1, characterized in that, The physical film thickness of the ZrO2 layer, which is configured as the third layer from the substrate side, is 11 nm to 20 nm.

3. The plastic optical product according to claim 1, characterized in that, The physical film thickness of the SiO2 layer configured as the fourth layer from the substrate side is 200 nm to 245 nm.

4. The plastic optical product according to claim 1, characterized in that, The sum of the physical film thicknesses from the ZrO2 layer, which is the layer closest to the substrate, to the SiO2 layer, which is the fourth layer from the substrate side, is 270 nm or more and 330 nm or less.

5. The plastic optical article according to claim 1, characterized in that, The intermediate film is a hard coating.

6. The plastic optical article according to claim 1, characterized in that, The visual reflectance of the surface on which the optical multilayer film is formed is less than 0.8%.

7. A type of plastic eyeglass lens, characterized in that, It uses the plastic optical article as described in any one of claims 1 to 6.

Images