Injection molding products

Abstract

The present application relates to an injection-molded article or eyewear. The present application relates to an optically compensated injection-molded article or eyewear, which can provide an injection-molded article that eliminates optical defects such as rainbows that occur in the injection-molded article or eyewear.

Description

[Technical field]

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0079570, filed on July 2, 2019, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0003] Technical Field This application relates to injection molded articles. [Background technology]

[0004] Injection molding is a typical plastic molding method. Injection molding is one of the plastic molding methods using a mold, in which a material such as plastic is heated and melted, then injected into a mold and cooled to obtain a product of a desired shape. FIG. 1 is an example of an injection molding machine. As shown in FIG. 1, an injection molding machine may be composed of a hopper C for introducing a material, a cylinder A in which the introduced material is melted by heating, and a nozzle B for injecting the melted material into a mold D. Using an injection molding machine as shown in FIG. 1, a material is introduced into the hopper C, melted in the cylinder A, and then injected into the mold D using the nozzle B. In FIG. 1, the mold D is in an open form, but the mold D may be closed when the material is introduced, and the mold D can be opened after the material is cooled to obtain a product. The injection molding machine and the injection molding method shown in FIG. 1 are only examples, and various other molding machines can be used to obtain injection molded products in various ways.

[0005] The injection molding method has an advantage that it can obtain the desired product at a low cost compared to other methods such as the extrusion method, which is also a plastic processing method. However, the injection molding method applies a lot of stress to the material and the direction of the stress is random, so a lot of phase difference occurs in the product and the optical axis direction is also random. Therefore, if the injection molding product is a product that is worn or used outdoors, such as glasses or goggles, it induces a defect called the rainbow phenomenon outdoors.

[0006] Figures 2 and 3 are photographs of a product manufactured in the form of goggles, Figure 2 is a photograph of a product manufactured by injection molding, and Figure 3 is a photograph of a product manufactured by extrusion. Figures 2 and 3 are both observed under a polarized light source, and as shown in the figures, the product manufactured by injection molding (Figure 2) exhibits severe rainbow phenomenon. Summary of the Invention [Problem to be solved by the invention]

[0007] The present application relates to an injection molded article. Specifically, the present application relates to an optically compensated injection molded article, and more particularly to an injection molded article that is free of optical defects such as rainbows that occur in the injection molded article. [Means for solving the problem]

[0008] In the present specification, the terms vertical, parallel, orthogonal, or horizontal and the numerical values ​​of the angles used to define the angles refer to substantially vertical, parallel, orthogonal, or horizontal and the numerical values ​​of the substantially said angles within a range that does not impair the intended effect. Therefore, the range of the numerical values ​​of the vertical, parallel, orthogonal, or horizontal and the angles may include errors such as manufacturing errors or variations. For example, each of the above cases may include an error within about ±5 degrees, an error within ±4.5 degrees, an error within ±4 degrees, an error within ±3.5 degrees, an error within ±3 degrees, an error within ±2.5 degrees, an error within ±2 degrees, an error within ±1.5 degrees, an error within ±1 degree, an error within ±0.9 degrees, an error within ±0.8 degrees, an error within ±0.7 degrees, an error within ±0.6 degrees, an error within ±0.5 degrees, an error within ±0.4 degrees, an error within ±0.3 degrees, an error within ±0.2 degrees, or an error within ±0.1 degrees.

[0009] In the present specification, when the measurement temperature affects the physical property, the physical property is measured at room temperature unless otherwise specified. The term "room temperature" refers to a temperature without heating or cooling, and may refer to any one of temperatures within a range of about 10°C to 30°C, for example, about 15°C or more, 18°C ​​or more, 20°C or more, or about 23°C or more, and about 27°C or less. In addition, unless otherwise specified, the unit of temperature referred to in the present specification is °C.

[0010] The phase difference and refractive index referred to in this specification mean the phase difference and refractive index for light with a wavelength of about 550 nm, respectively, unless otherwise specified.

[0011] Unless otherwise specified, the angle between any two directions referred to in this specification may be an acute angle between the acute or obtuse angles between the two directions, or a smaller angle between angles measured in a clockwise or counterclockwise direction. Thus, unless otherwise specified, the angles referred to in this specification are positive numbers. However, in some cases, in order to indicate the measurement direction between angles measured in a clockwise or counterclockwise direction, one of the angles measured in the clockwise direction and the angle measured in the counterclockwise direction may be expressed as a positive number and the other angle may be expressed as a negative number.

[0012] In this specification, the terms "injection-molded product" and "injection-molded body" refer to different objects. An injection-molded body is an object obtained by applying a plastic material to injection molding, and an injection-molded body refers to a product including the above-mentioned object together with other components (e.g., a retardation film, etc.).

[0013] In this specification, the in-plane retardation of the retardation film is a physical quantity derived by the following formula 1, and the thickness direction retardation is a physical quantity derived by the following formula 2.

[0014] [Formula 1]

[0015] Rin = d × (nx-ny)

[0016] [Formula 2]

[0017] Rth = d × (nz-ny)

[0018] In the formulas 1 and 2, d is the thickness of the retardation film, and nx, ny, and nz are the refractive indexes of the retardation film in the slow axis direction, the fast axis direction, and the thickness direction, respectively. The meanings of the slow axis and the fast axis are as known in the art.

[0019] In the present application, by applying a predetermined retardation film in a predetermined arrangement together with an injection-molded body, optical defects arising from the injection-molded body can be eliminated.

[0020] In one example, the optical compensation injection molded article of the present application may include an injection molded article and a retardation film formed or disposed on at least one surface of the injection molded article.

[0021] The specific type of the injection molded product is not particularly limited, and all types of injection molded products that have various known shapes and are found to have optical defects such as rainbow phenomenon can be applied to the present application. In particular, injection molded products such as eyewear that are worn or used outdoors and in which optical defects are more problematic are examples of representative injection molded products to which the present application is applied. In such cases, the specific shape of the eyewear is not particularly limited, and may have, for example, the shapes shown in Figs. 2 and 3.

[0022] The shape of the injection molded article is not particularly limited, and may be, for example, a two-dimensional shape such as a film or sheet, or may have a three-dimensional shape or other complex shape.

[0023] The injection molded article applied in the present application may have a retardation of, for example, 800 nm to 3,000 nm relative to a wavelength of 550 nm. Such a retardation may be expressed by orienting the plastic material due to stress applied during the formation process of the injection molded article. The retardation may be, for example, about 850 nm or more, 900 nm or more, 950 nm or more, 1000 nm or more, 1100 nm or more, 1200 nm or more, 1300 nm or more, 1400 nm or more, 1500 nm or more, 1600 nm or more, 1700 nm or more, 1800 nm or more, or 1900 nm or more, or about 2900 nm or less, 2800 nm or less, 2700 nm or less, 2600 nm or less, 2500 nm or less, 2400 nm or less, 2300 nm or less, 2200 nm or less, 2100 nm or less, or 2000 nm or less. The retardation of the injection molded body is measured by the method described in the examples of the present specification. In one example, the retardation may be an in-plane retardation of the injection molded body. The in-plane direction of the injection molded body is a direction approximately parallel to the in-plane direction of the retardation film applied to the injection molded body. Since stress is randomly applied to the injection molded body during the formation process, the slow axis is also randomly formed, and therefore a fixed slow axis cannot be defined.

[0024] The type of material forming the injection molded body is not particularly limited, and all plastic materials generally used in the manufacture of injection molded bodies may be used in the present application. Examples of such materials include one or more plastics selected from the group consisting of polyvinyl chloride, polyolefin, polyester, nylon, polyamide, polysulfone, polyetherimide, polyethersulfone, polyphenylene sulfide, polyetherketone, polyetheretherketone, ABS resin (acrylonitrile butadiene styrene copolymer), polystyrene, polybutadiene, polyacrylate, polyacrylonitrile, polyacetal, polycarbonate, polyphenylene ether, EVA resin (Ethylene vinyl acetate copolymer), polyvinyl acetate, liquid crystal polymer, ethylene-tetrafluoroethylene copolymer, polyvinyl fluoride, polyvinylidene fluoride, polyvinylidene chloride, and Teflon. Thus, the injection molded body may include the plastics. In addition, the mixture of two or more of the above-listed plastics includes a simple mixture of two or more of the above polymers, as well as a modified resin or copolymer produced by polymerizing the monomers constituting each of the above polymers.

[0025] In the present application, a retardation film having large optical anisotropy is disposed at a predetermined position on at least one surface of the injection molded body as a retardation film, thereby eliminating optical defects such as the rainbow phenomenon that occurs from the injection molded body alone.

[0026] In this specification, the retardation film having large optical anisotropy can be called asymmetric retardation film. In addition, such a retardation film having large optical anisotropy may also have anisotropic mechanical properties. The retardation film having large optical anisotropy above means that the retardation film has an in-plane retardation described later.

[0027] In one example, the in-plane retardation of the retardation film may be about 1,000 nm or more. The in-plane retardation is a value for light with a wavelength of 550 nm, and is a physical quantity defined by the above-mentioned mathematical formula 1. In other examples, the in-plane retardation of the retardation film may be 1500 nm or more, 2000 nm or more, 2500 nm or more, 3000 nm or more, 3500 nm or more, 4000 nm or more, 4500 nm or more, 5000 nm or more, 5500 nm or more, 6000 nm or more, 6500 nm or more, 7000 nm or more, 7500 nm or more, 8000 nm or more, 8500 nm or more, 9000 nm or more, or 9500 nm or more; The wavelength may be about 00 nm or less, 60,000 nm or less, 50,000 nm or less, 40,000 nm or less, 30,000 nm or less, 20,000 nm or less, 15,000 nm or less, 14,000 nm or less, 13,000 nm or less, 12,000 nm or less, 10,000 nm or less, 9,500 nm or less, 9,000 nm or less, 8,500 nm or less, 8,000 nm or less, 7,500 nm or less, 7,000 nm or less, 6,500 nm or less, 6,000 nm or less, 5,500 nm or less, 5,000 nm or less, or 4,500 nm or less.

[0028] The specific type of the retardation film applicable to the present application is not particularly limited as long as it exhibits the in-plane retardation in the range mentioned above. For example, an anisotropic polymer film or sheet imparted with optical anisotropy by stretching, a liquid crystal film, or a liquid crystal coating layer may be used as the retardation film. Examples of the polymer film include polyolefin films such as polyethylene films or polypropylene films, cycloolefin polymer (COP) films such as polynorbornene films, cellulose ester polymer films such as polyvinyl chloride films, polyacrylonitrile films, polysulfone films, polyacrylate films, PVA (poly(vinyl alcohol)) films, or TAC (Triacetyl cellulose) films, polyester films, polycarbonate films, and copolymer films of two or more monomers among the monomers forming the polymers. The liquid crystal film or liquid crystal coating layer is a retardation film formed using a liquid crystal polymer or a polymerizable liquid crystal compound (so-called RM (Reactive MEsogen)).

[0029] As one example, the retardation film may be a polyester film such as a PET (poly(ethylene terephthalate)) film. That is, films exhibiting an in-plane retardation in the above-mentioned range are well known in the industry, and in the case of polymer films, such films exhibit not only large optical anisotropy but also large asymmetry in mechanical properties due to high stretching during the manufacturing process. A representative example of such a retardation film that is well known in the industry is a stretched polyester film such as a stretched PET (poly(ethylene terephthalate)) film.

[0030] Therefore, as an example, a polyester film such as a PET film may be used as the retardation film, but the type of retardation film applicable in the present application is not limited thereto.

[0031] There is no particular limitation on the thickness direction retardation of the retardation film. That is, for the optical compensation of the injection molded article, it is necessary to control the in-plane retardation and the arrangement of the slow axis of the retardation film, and the thickness direction retardation can be appropriately selected within a range that does not impair the intended effect. The thickness direction retardation of the retardation film is usually within the range of -10000nm to 10000nm (based on a wavelength of 550nm). The thickness direction retardation is, for example, -9000nm or more, -8000nm or more, -7000nm or more, -6000nm or more, -5000nm or more, -4000nm or more, -3000nm or more, -2000nm or more, -1000nm or more, -900nm or more, -800nm ​​or more, -700nm or more, -600nm or more, -500nm or more, -400nm or more, -300nm or more, -200nm or more, -100nm It may be about 9000nm or less, 8000nm or less, 7000nm or less, 6000nm or less, 5000nm or less, 4000nm or less, 3000nm or less, 2000nm or less, 1000nm or less, 900nm or less, 800nm ​​or less, 700nm or less, 600nm or less, 500nm or less, 400nm or less, 300nm or less, 200nm or less, 100nm or less, or 50nm or less.

[0032] Such a retardation film can have the characteristics of a so-called +A film (a film that satisfies the following formula 3), -A film (a film that satisfies the following formula 4), +B film (a film that satisfies the following formula 5), ​​Z film (a film that satisfies the following formula 6), or -B film (a film that satisfies the following formula 7).

[0033] [Formula 3]

[0034] nx>ny=nz

[0035] [Formula 4]

[0036] nx=nz>ny

[0037] [Formula 5]

[0038] nz>nx>ny

[0039] [Formula 6]

[0040] nx>nz>ny

[0041] [Formula 7]

[0042] nx>ny>nz

[0043] In formulas 3 to 7, nx, ny, and nz are defined as in formulas 1 and 2.

[0044] The thickness of the retardation film is not particularly limited, and an appropriate thickness can be selected in consideration of the refractive index anisotropy of the retardation film so that the in-plane retardation in the above-mentioned range can be ensured.

[0045] For proper optical compensation, the slow axis of the retardation film needs to be controlled in relation to the injection molded body. As described above, the slow axis of the injection molded body is randomly formed, so a compensation method considering the slow axis of the injection molded body cannot be applied. However, the purpose can be achieved by controlling the slow axis of the retardation film in relation to the injection direction of the injection molded body. The injection direction means the direction in which the molten plastic material is injected into the mold during the injection molding process.

[0046] In the injection molded article of the present application, the angle between the slow axis of the retardation film and the injection direction of the injection molded body may be within a range of 0 degrees to 80 degrees. By adjusting the angle within such a range, it is possible to provide an injection molded article that is appropriately optically compensated. The angle may be an angle measured clockwise or counterclockwise based on the injection direction in a state where the injection molded body is located below the retardation film.

[0047] In other examples, the angle may be 5 degrees or more, 10 degrees or more, 15 degrees or more, 20 degrees or more, 25 degrees or more, 30 degrees or more, 35 degrees or more, 40 degrees or more, 45 degrees or more, 50 degrees or more, 55 degrees or more, 60 degrees or more, 65 degrees or more, or 70 degrees or more, or it may be 75 degrees or less, 70 degrees or less, 65 degrees or less, 60 degrees or less, 55 degrees or less, 50 degrees or less, 45 degrees or less, 40 degrees or less, 35 degrees or less, 30 degrees or less, or 25 degrees or less.

[0048] There is no particular limitation on the method of including the retardation film in the injection molded product so as to have the injection direction and the above-mentioned arrangement. For example, when the surface of the injection molded product on which the retardation film is arranged is a substantially flat surface, the retardation film can be attached to the surface in consideration of the slow axis and injection direction of the retardation film, or the retardation film can be formed by coating the surface with a material capable of forming a retardation layer, such as a liquid crystal composition. Also, when the surface of the injection molded product on which the retardation film is arranged is not flat, the retardation film can be bent to follow the surface and attached to the surface in consideration of the slow axis and injection direction, or the retardation film can be formed by coating the surface with a material capable of forming a retardation layer, such as a liquid crystal composition.

[0049] The injection molded product may include known components required in addition to the injection molded body and the retardation film. Examples of such components include, but are not limited to, a pressure sensitive adhesive or an adhesive layer for attaching the retardation film to the injection molded body, and other components may be included as necessary. For example, when the injection molded product is eyewear used in AR (Augmented Reality) or VR (Virtual Reality) technology, the injection molded product may additionally include components (e.g., a transmittance variable device, etc.) for implementing the AR or VR.

[0050] The present application also relates to said injection molded article as eyewear.

[0051] In such a case, the injection-molded product (eyewear) may include an eyewear body which is an injection-molded body; and a retardation film which is disposed on at least one surface of the eyewear body and has an in-plane retardation of 1,000 nm or more for light with a wavelength of 550 nm.

[0052] The category of eyewear may include eyewear applicable to various uses, such as sports goggles, eyewear for implementing VR or AR, and various other eyewear including general glasses and sunglasses, etc. There is no particular limitation on the shape of the eyewear, and various shapes including known shapes, such as the shapes shown in Figs. 2 and 3, may be applied.

[0053] The eyewear body typically includes a left eye region and a right eye region, the left eye region being the region where the left eye is positioned when the wearer wears the eyewear (e.g., the left eye lens region), and the right eye region being the region where the right eye is positioned when the wearer wears the eyewear (e.g., the right eye lens region).

[0054] The same description of the injection molded product can be applied to the above eyewear.

[0055] For example, the eyewear body may have a phase difference with respect to a wavelength of 550 nm within a range of 800 nm to 3,000 nm. In other examples, the phase difference may be about 850 nm or more, 900 nm or more, 950 nm or more, 1000 nm or more, 1100 nm or more, 1200 nm or more, 1300 nm or more, 1400 nm or more, 1500 nm or more, 1600 nm or more, 1700 nm or more, 1800 nm or more, or 1900 nm or more, or about 2900 nm or less, 2800 nm or less, 2700 nm or less, 2600 nm or less, 2500 nm or less, 2400 nm or less, 2300 nm or less, 2200 nm or less, 2100 nm or less, or 2000 nm or less. The phase difference is a result of measurement using the method described in the examples of this specification. Since stress is randomly applied to the injection molded article during the molding process, the slow axis of the eyewear may also be formed randomly.

[0056] The type of material forming the eyewear body is not particularly limited, and any plastic material that is generally used in the manufacture of eyewear may be used. In general, the eyewear body is manufactured using nylon, polycarbonate, or the like.

[0057] The above-mentioned contents may be equally applied to the characteristics and type, for example, retardation and material, of the retardation film applied to at least one surface of the eyewear body.

[0058] For example, the in-plane retardation of the retardation film with respect to a wavelength of 550 nm may be about 1,000 nm or more. Other examples include 1500 nm or more, 2000 nm or more, 2500 nm or more, 3000 nm or more, 3500 nm or more, 4000 nm or more, 4500 nm or more, 5000 nm or more, 5500 nm or more, 6000 nm or more, 6500 nm or more, 7000 nm or more, 7500 nm or more, 8000 nm or more, 8500 nm or more, 9000 nm or more, or 9500 nm or more. It may be about 80,000 nm or less, 70,000 nm or less, 60,000 nm or less, 50,000 nm or less, 40,000 nm or less, 30,000 nm or less, 20,000 nm or less, 15,000 nm or less, 14,000 nm or less, 13,000 nm or less, 12,000 nm or less, 10,000 nm or less, 9,500 nm or less, 9,000 nm or less, 8,500 nm or less, 8,000 nm or less, 7,500 nm or less, 7,000 nm or less, 6,500 nm or less, 6,000 nm or less, 5,500 nm or less, 5,000 nm or less, or 4,500 nm or less.

[0059] The retardation film may also be the above-mentioned polymer film, liquid crystal film, or liquid crystal coating layer.

[0060] In the case of eyewear, the slow axis of the retardation film needs to be controlled in relation to the eyewear body for appropriate optical compensation. That is, the angle between the emission direction of the eyewear body and the slow axis of the retardation film may be within a range of 0 degrees to 80 degrees. The angle may be an angle measured clockwise or counterclockwise based on the emission direction with the eyewear body located below the retardation film. In other examples, the angle may be 5 degrees or more, 10 degrees or more, 15 degrees or more, 20 degrees or more, 25 degrees or more, 30 degrees or more, 35 degrees or more, 40 degrees or more, 45 degrees or more, 50 degrees or more, 55 degrees or more, 60 degrees or more, 65 degrees or more, or 70 degrees or more, or 75 degrees or less, 70 degrees or less, 65 degrees or less, 60 degrees or less, 55 degrees or less, 50 degrees or less, 45 degrees or less, 40 degrees or less, 35 degrees or less, 30 degrees or less, or 25 degrees or less.

[0061] Usually, in the case of the eyewear body, the virtual line connecting the centers of the left eye region and the right eye region is often perpendicular to the emission direction. Therefore, in such a case, the angle between the slow axis of the retardation film and the virtual line may be within a range of 10 degrees to 170 degrees. The angle may be an angle measured clockwise or counterclockwise from the virtual line to the slow axis.

[0062] The center of the left eye region or right eye region may be the center of gravity of the left eye region or right eye region, respectively, or may be the region corresponding to the left eye and right eye of a wearer wearing the eyewear.

[0063] Other examples of the angle include 15 degrees or more, 20 degrees or more, 25 degrees or more, 30 degrees or more, 35 degrees or more, 40 degrees or more, 45 degrees or more, 50 degrees or more, 55 degrees or more, 60 degrees or more, 65 degrees or more, 70 degrees or more, 75 degrees or more, 80 degrees or more, 85 degrees or more, 90 degrees or more, 95 degrees or more, 100 degrees or more, 105 degrees or more, 110 degrees or more, 115 degrees or more, 120 degrees or more, 125 degrees or more, 130 degrees or more, 135 degrees or more, 140 degrees or more, 145 degrees or more, 150 degrees or more, and 155 degrees. The angle may be 160 degrees or more, or 165 degrees or less, 160 degrees or less, 155 degrees or less, 150 degrees or less, 145 degrees or less, 140 degrees or less, 135 degrees or less, 130 degrees or less, 125 degrees or less, 120 degrees or less, 115 degrees or less, 110 degrees or less, 105 degrees or less, 100 degrees or less, 95 degrees or less, 90 degrees or less, 85 degrees or less, 80 degrees or less, 75 degrees or less, 70 degrees or less, 65 degrees or less, 60 degrees or less, 55 degrees or less, 50 degrees or less, 45 degrees or less, or about 40 degrees or less.

[0064] The eyewear may also include other components in addition to the eyewear body and the retardation film.

[0065] In the above manner, eyewear in which optical defects such as rainbow phenomenon are not observed can be provided. Effect of the Invention

[0066] The present application relates to an optically compensated injection molded article, which can provide an injection molded article that eliminates optical defects such as the rainbow phenomenon that occurs in injection molded articles. [Brief description of the drawings]

[0067] [Figure 1] FIG. 1 illustrates the structure of an exemplary injection molding machine. [Diagram 2] 1 is a photograph showing the rainbow phenomenon in an injection molded product that was not optically compensated. [Diagram 3] 1 is a photograph of an extrusion molded product. [Figure 4] 3 is a photograph confirming the optical properties of the injection-molded product of Example 1. [Diagram 5]4 is a photograph confirming the optical properties of the injection-molded product of Example 2. [Figure 6] 1 is a photograph confirming the optical properties of the injection-molded product of Example 3. [Figure 7] 1 is a photograph confirming the optical properties of the injection-molded product of Example 4. [Figure 8] 3 is a photograph confirming the optical properties of the injection-molded product of Comparative Example 1. [Figure 9] 4 is a photograph confirming the optical properties of the injection-molded product of Comparative Example 2. [Figure 10] 1 is a photograph confirming the optical properties of the injection-molded product of Comparative Example 3. [Figure 11] 1 is a photograph confirming the optical properties of the injection-molded product of Comparative Example 4. [Figure 12] 1 is a photograph of an injection molded body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0068] The present application will be described in detail with reference to the following examples, but the scope of the present application is not limited to the following examples.

[0069] 1. Evaluation of phase difference

[0070] The in-plane retardation (Rin) of the retardation film and the injection molded body was measured for light of 550 nm wavelength using Agilent UV / VIS spectroscope 8453 equipment by the following method. Two polarizers were installed in the UV / VIS spectroscope so that the transmission axes were perpendicular to each other, and the retardation film was installed between the two polarizers so that the slow axis of the retardation film was at 45 degrees to the transmission axes of the two polarizers, and then the transmittance was measured according to wavelength. In the case of the injection molded body, since the direction of the slow axis is not constant, it was installed so that the injection direction was at 45 degrees to the transmission axes of the two polarizers. The phase retardation order of each peak was obtained from the transmittance graph according to wavelength. Specifically, the waveform in the transmittance graph according to wavelength satisfies the following formula A, and the maximum peak (Tmax) condition in the sine waveform satisfies the following formula B. When λmax is found in formula A, T in formula A and T in formula B are the same, so the formula is expanded. The formula is expanded for n+1, n+2, and n+3, n and n+1 formulas are rearranged, R is eliminated, and n is rearranged with λn and λn+1 formulas, and the following formula C is derived. Since n and λ are known based on the fact that T in formula A and T in formula B are the same, R is calculated for each λn, λn+1, λn+2, and λn+3. A linear trend line of R value by wavelength is obtained for the four points, and the R value for the formula 550 nm is calculated. The function of the linear trend line is Y=ax+b, where a and b are integers. The Y value when 550 nm is substituted for x in the function is the Rin value for light with a wavelength of 550 nm.

[0071] [Formula A]

[0072] T=sin 2 [(2πR / λ)]

[0073] [Formula B]

[0074] T=sin 2 [((2n+1)π / 2)]

[0075] [Formula C]

[0076] n=(λn-3λn+1) / (2λn+1+1-2λn)

[0077] In the above, R means the in-plane retardation (Rin), λ means the wavelength, and n means the peak order of the sine wave.

[0078] <Example 1>

[0079] The injection molded body was applied to the formation of the eyewear body, and was manufactured by injection molding polycarbonate (PC). A PC plate (injection molded body) having a rectangular shape as shown in FIG. 12 was applied. As shown in FIG. 12, the injection molded body exhibited an intense rainbow phenomenon under a polarized light source. Meanwhile, the injection direction of the injection molded body was approximately perpendicular to the horizontal direction (arrow direction) described in the drawing. The injection molded body was optically compensated using a PET (poly(ethylene terephthalate)) film (SKC's 125 μm PET product) with an in-plane phase difference of about 4400 nm for a wavelength of 550 nm as a retardation film. At this time, the angle of the slow axis was set to be within a range of about 23 degrees to 28 degrees when measured counterclockwise based on the injection direction of the injection molded body (direction perpendicular to the arrow direction in FIG. 12). FIG. 4 is a photograph showing the results, and as shown in the photograph, no optical defects such as rainbow phenomenon were observed in the area where the retardation film was present.

[0080] <Example 2>

[0081] Optical compensation was performed in the same manner as in Example 1, except that the angle of the slow axis of the retardation film was within a range of about 67 degrees to 74 degrees when measured clockwise based on the injection direction of the injection molded body (the direction perpendicular to the arrow direction in FIG. 12). Figure 5 is a photograph showing the results, and as shown in the photograph, no optical defects such as the rainbow phenomenon were observed in the area where the retardation film was present.

[0082] <Example 3>

[0083] Optical compensation was performed on the same injection molded body as in Example 1 using a PET (poly(ethylene terephthalate)) film (a film of a grade showing the in-plane retardation of 550 nm wavelength among SRF products of Toyobo) with an in-plane retardation of about 9800 nm for a wavelength of 550 nm as the retardation film. At this time, the angle of the slow axis was set to be within a range of about 38 degrees to 48 degrees when measured clockwise based on the injection direction of the injection molded body (direction perpendicular to the arrow direction in FIG. 12). FIG. 6 is a photograph showing the results, and as shown in the photograph, no optical defects such as the rainbow phenomenon were observed in the area where the retardation film was present.

[0084] <Example 4>

[0085] Optical compensation was performed in the same manner as in Example 3, except that the angle of the slow axis of the retardation film was within a range of about 45 degrees to 52 degrees when measured counterclockwise with reference to the injection direction of the injection molded body (the direction perpendicular to the arrow direction in FIG. 12). Figure 7 is a photograph showing the results, and as shown in the photograph, no optical defects such as the rainbow phenomenon were observed in the area where the retardation film was present.

[0086] <Comparative Example 1>

[0087] Except for the angle of the slow axis of the retardation film being about 90 degrees with respect to the injection direction of the injection molded body (the direction perpendicular to the arrow direction in FIG. 12), optical compensation was performed in the same manner as in Example 1. Figure 8 is a photograph showing the results, and as shown in the photograph, a rainbow phenomenon was observed even in the area where the retardation film was present, confirming optical defects.

[0088] <Comparative Example 2>

[0089] Optical compensation was performed in the same manner as in Example 1, except that the angle of the slow axis of the retardation film was within a range of about 85 degrees when measured counterclockwise based on the injection direction of the injection molded body (the direction perpendicular to the arrow direction in Figure 12). Figure 9 is a photograph showing the results, and as can be seen in the photograph, a rainbow phenomenon was observed even in the area where the retardation film was present, confirming optical defects.

[0090] <Comparative Example 3>

[0091] Except for the angle of the slow axis of the retardation film being about 90 degrees with respect to the injection direction of the injection molded body (the direction perpendicular to the arrow direction in FIG. 12), optical compensation was performed in the same manner as in Example 3. Figure 10 is a photograph showing the results, and as shown in the photograph, a rainbow phenomenon was observed even in the area where the retardation film was present, confirming optical defects.

[0092] <Comparative Example 4>

[0093] Optical compensation was performed in the same manner as in Example 3, except that the angle of the slow axis of the retardation film was within a range of about 85 degrees when measured counterclockwise based on the injection direction of the injection molded body (the direction perpendicular to the arrow direction in Figure 12). Figure 11 is a photograph showing the results, and as shown in the photograph, a rainbow phenomenon was observed even in the area where the retardation film was present, confirming optical defects.

Claims

1. An eyewear body having a left eye region and a right eye region as an injection molded body, A retardation film having an in-plane retardation of 1,000 nm or more for light with a wavelength of 550 nm, an injection direction of the injection molded body is perpendicular to a virtual line connecting a center of the left eye region and a center of the right eye region; The eyewear body, which is the injection molded article, has a randomly formed slow axis, the eyewear body which is the injection molded article has a phase difference with respect to light having a wavelength of 550 nm within a range of 800 nm to 3,000 nm; The retardation film is disposed on at least one surface of the eyewear body which is the injection molded body, The retardation film has one slow axis, The angle between the slow axis of the retardation film and the emission direction is within a range of 5 degrees to 80 degrees, The eyewear, wherein an angle formed by a virtual line connecting the center of gravity of the left eye region and the center of gravity of the right eye region of the eyewear body and a slow axis of the retardation film is within a range of 10 degrees to 170 degrees.

2. The eyewear according to claim 1, wherein the injection-molded article is a molded article containing one or more plastics selected from the group consisting of polyvinyl chloride, polyolefin, polyester, nylon, polyamide, polysulfone, polyetherimide, polyethersulfone, polyphenylene sulfide, polyetherketone, polyetheretherketone, ABS resin, polystyrene, polybutadiene, polyacrylate, polyacrylonitrile, polyacetal, polycarbonate, polyphenylene ether, EVA resin, polyvinyl acetate, liquid crystal polymer, ethylene-tetrafluoroethylene copolymer, polyvinyl fluoride, polyvinylidene fluoride, polyvinylidene chloride, and Teflon (registered trademark).

3. The eyewear according to claim 1 or 2, wherein the retardation film has an in-plane retardation of 2,000 nm or more at a wavelength of 550 nm.

4. The eyewear according to claim 1 , wherein the retardation film has an in-plane retardation of 3,000 nm or more at a wavelength of 550 nm.

5. The eyewear according to claim 1 , wherein the retardation film is a polymer film or a liquid crystal film.

Images