Polarizing curved laminate and lens manufacturing method

Abstract

To provide a polarizing curved laminate and a lens manufacturing method which enable manufacture of a lens for spectacle having a good yield and excellent reliability.SOLUTION: A polarizing curved laminate 10 includes a polarizing film 13, a first resin layer 11 which is provided on one surface side of the polarizing film 13 and mainly contains a polycarbonate-based resin, and a second resin layer 12 which is provided on the other surface side of the polarizing film 13 and mainly contains a polycarbonate-based resin, and is curved, wherein in a curved convex face of the polarizing curved laminate 10, when a radius of curvature in a first axial direction set in plan view of the polarizing curved laminate 10 is represented by R1[mm], and a radius of curvature in a second axial direction perpendicular to the first axis is represented by R2[mm], one of the following expression (A) and the following expression (B) is satisfied. Expression (A): 0.80<R1 / √(R1 R2)<0.98. Expression (B): 1.02<R2 / √(R1 R2)<1.25.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing polarizing curved laminates and lenses. [Background technology]

[0002] BACKGROUND ART There has been proposed a lens for eyeglasses that includes a polarizing laminate (resin substrate) configured such that both sides of a polarizing film are covered with coating layers mainly made of polycarbonate-based resin, polyamide-based resin, or the like.

[0003] This lens (eyeglass lens) is manufactured by, for example, punching a polarizing laminate having an overall flat shape into a predetermined shape, such as a circle in a plan view, with protective films attached to both sides of the polarizing laminate. This polarizing laminate is then subjected to a heat bending process under heat to form a curved polarizing curved laminate. The protective films are then peeled off from the polarizing curved laminate, and the polarizing curved laminate is placed in a mold having a curved recess so that the recess of the mold abuts against the convex portion of the polarizing curved laminate, and a resin layer composed primarily of a resin material such as a polycarbonate resin or a polyamide resin is then formed on the concave surface of the polarizing curved laminate using insert injection molding (see, for example, Patent Document 1).

[0004] In such lens manufacturing methods, the polarizing curved laminate that has been curved by thermal bending is generally designed so that the radius of curvature of the convex portion is approximately the same as the radius of curvature of the concave portion of the mold used in the insert injection molding method, thereby causing the polarizing curved laminate to be adsorbed to the mold.

[0005] However, if the radius of curvature of the convex portion of the polarizing curved laminate and the radius of curvature of the concave portion of the mold used in insert injection molding are set to be approximately the same, when manufacturing a lens by insert injection molding, i.e., when forming a resin layer on the concave surface of the polarizing curved laminate, a slight misalignment in the installation position of the polarizing curved laminate with respect to the mold or the environment in which the polarizing curved laminate is adsorbed may prevent the polarizing curved laminate from being adsorbed to the mold with sufficient adhesiveness, causing the polarizing curved laminate to fall off from the mold, resulting in a decrease in the yield of the lenses manufactured. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-294445 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a polarizing curved laminate and a lens manufacturing method that enable the manufacture of eyeglass lenses with high yield and excellent reliability. [Means for solving the problem]

[0008] These objects can be achieved by the present invention as set forth in (1) to (5) below. (1) a polarizing film; a curved polarizing curved laminate comprising a first resin layer provided on one surface of the polarizing film and a second resin layer provided on the other surface of the polarizing film, A polarizing curved laminate characterized in that, on the curved convex surface of the polarizing curved laminate, when viewed in a plane, the radius of curvature in a first axis direction set in the polarizing curved laminate is R1 [mm] and the radius of curvature in a second axis direction perpendicular to the first axis is R2 [mm], the polarizing curved laminate satisfies at least one of the following formulas (A) and (B): Formula (A): 0.80 <R1 / √(R1·R2)<0.98 Formula (B): 1.02 <R2 / √(R1·R2)<1.25

[0009] (2) When the formula (A) is satisfied, The polarizing curved laminate according to (1) above, wherein R1 / R2 is 0.55 or more and 0.97 or less.

[0010] (3) When the above formula (B) is satisfied, The polarizing curved laminate according to (1) above, wherein R2 / R1 is 0.55 or more and 0.97 or less.

[0011] (4) The polarizing curved laminate according to any one of (1) to (3) above, wherein the polarization axis of the polarizing film and the first axis are parallel to each other.

[0012] (5) A first step of obtaining the polarizing curved laminate described in (1) above; Radius of curvature in one direction R B1 [mm], radius of curvature R in the orthogonal direction perpendicular to the one direction B2 a second step of closely contacting the polarizing curved laminate with a mold having a curved concave surface of 1 / 4 [mm], with the other surface of the polarizing curved laminate that is the curved convex surface facing the mold, and with the first axis direction aligned with the one direction; and a third step of forming a resin layer bonded to the polarizing curved laminate on the side of the polarizing curved laminate opposite the mold while maintaining the polarizing curved laminate in close contact with the mold. [Effects of the Invention]

[0013] According to the present invention, when manufacturing eyeglass lenses using a polarizing curved laminate that has been curved by thermal bending, i.e., when forming a resin layer on the curved concave surface of the polarizing curved laminate, it is possible to reliably suppress or prevent the polarizing curved laminate from falling off from a mold used to form the resin layer. In other words, the polarizing curved laminate can be adsorbed to the mold with excellent adsorption properties. Therefore, highly reliable lenses can be manufactured with a high yield. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view of an embodiment of sunglasses with lenses having the polarizing curved laminate of the present invention. [Figure 2] FIG. 2 is a longitudinal cross-sectional view showing an embodiment of the polarizing curved laminate shown in FIG. [Figure 3] 1A to 1C are schematic diagrams illustrating a method for manufacturing a lens having a polarizing curved laminate. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, a polarizing curved laminate and a method for manufacturing a lens according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

[0016] A lens 30 including the polarizing curved laminate 10 of the present invention is used, for example, as part of sunglasses 100, a type of eyeglasses. Therefore, hereinafter, first, sunglasses 100 including this lens 30 will be described before describing a method for manufacturing a lens of the present invention.

[0017] <Sunglasses> Fig. 1 is a perspective view showing an embodiment of sunglasses equipped with lenses having a polarizing curved laminate of the present invention. Fig. 2 is a longitudinal cross-sectional view showing the embodiment of the polarizing curved laminate shown in Fig. 1. In Fig. 1, when the sunglasses are worn on a user's head, the surface of the lens facing the user's eyes is referred to as the back side, and the opposite side is referred to as the front side. In Fig. 2, for convenience of explanation, the upper side of Fig. 2 is referred to as "top" and the lower side is referred to as "bottom."

[0018] As shown in FIG. 1, the sunglasses 100 include a frame 20 and lenses 30 (eyeglass lenses).

[0019] In this specification, the term "lens" includes both those having a light-condensing function and those not having a light-condensing function.

[0020] The frame 20 is worn on the user's head and positions the lenses 30 near the front of the user's eyes.

[0021] The frame 20 has a rim portion 21, a bridge portion 22, temple portions 23, and a nose pad portion 24.

[0022] The rim portions 21 are ring-shaped and are provided one for each of the right and left eyes, with lenses 30 attached to the inside thereof. This allows the user to view external information through the lenses 30.

[0023] The bridge portion 22 is rod-shaped and is positioned in front of the upper part of the user's nose when the glasses are worn on the user's head, connecting the pair of rim portions 21 together.

[0024] The temple portions 23 are temple-shaped and connected to the edge of each rim portion 21 on the opposite side to the position where the bridge portions 22 are connected. The temple portions 23 are hung over the user's ears when wearing the glasses on the user's head.

[0025] The nose pads 24 are provided on the edges of the rims 21 that correspond to the user's nose when the sunglasses 100 are worn on the head of the user, and come into contact with the user's nose, with a shape that corresponds to the contacting part of the user's nose at this time. This allows the sunglasses 100 to be kept stably worn.

[0026] The constituent materials of the components of the frame 20 are not particularly limited, and may be, for example, various metal materials, various resin materials, etc. The shape of the frame 20 is not limited to that shown in the drawings, as long as it can be worn on the user's head.

[0027] The lenses 30 are eyeglass lenses that are attached to the rim portions 21. The lenses 30 are optically transparent, plate-shaped members that are curved outward, and include a resin layer 35 and a polarizing curved laminate 10.

[0028] The resin layer 35 is optically transparent and is located on the rear side of the lens. When the lens 30 is given a light-collecting function, the resin layer 35 has the light-collecting function.

[0029] The constituent material of the resin layer 35 is not particularly limited as long as it is a resin material that is optically transparent, but examples include various thermoplastic resins, thermosetting resins, and various curable resins such as photocurable resins, and one or more of these can be used in combination.

[0030] Examples of resin materials include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polyvinyl chloride, polystyrene, polyamide, polyimide, polycarbonate, poly-(4-methylpentene-1), ionomers, acrylic resins, polymethyl methacrylate, acrylonitrile-butadiene-styrene copolymers (ABS resins), acrylonitrile-styrene copolymers (AS resins), butadiene-styrene copolymers, polyesters such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyethers, polyether ketones (PEK), and polyether ethers. Examples of suitable resins include polyetherimide (PEEK), polyacetal (POM), polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluorine-based resins, epoxy resin, phenolic resin, urea resin, melamine resin, silicone resin, polyurethane, etc., as well as copolymers, blends, and polymer alloys primarily made of these. Among these, it is preferable that the resin layer 35 be the same as or be the same as the resin material constituting the first resin layer 11 of the polarizing curved laminate 10, which will be described later. This can improve the adhesion between the resin layer 35 and the polarizing curved laminate 10.

[0031] The thickness of the resin layer 35 is not particularly limited, but is preferably 0.5 mm or more and 5.0 mm or less, and more preferably 1.0 mm or more and 3.0 mm or less, for example, which allows the lens 30 to have both relatively high strength and light weight.

[0032] The polarizing curved laminate 10 is a curved resin substrate that is bonded to the outer surface of the resin layer 35, i.e., the curved convex surface, in a curved shape that corresponds to this shape, thereby imparting polarization to the sunglasses 100. As a result, the sunglasses 100 function as polarized sunglasses with polarization. This polarizing curved laminate 10 is composed of the polarizing curved laminate of the present invention, and a detailed description of this will be given later.

[0033] The polarizing curved laminate 10 is obtained by bending a polarizing laminate 15 having a flat overall shape into a curved shape in the manufacturing method of the lens 30 described below, and as shown in Figure 2, it comprises a polarizing film 13, a first resin layer 11 provided on one side of the polarizing film 13, and a second resin layer 12 provided on the other side of the polarizing film 13, and in this embodiment, it further comprises an adhesive layer 16 that bonds (adheres) the polarizing film 13 and the first resin layer 11, and an adhesive layer 17 that bonds (adheres) the polarizing film 13 and the second resin layer 12.

[0034] (Polarizing film 13) The polarizing film 13 has the function of extracting linearly polarized light having a polarization plane in a predetermined direction from incident light (unpolarized natural light), so that the light passing through the polarizing curved laminate 10 (polarizing laminate 15) becomes polarized.

[0035] The polarization degree of the polarizing film 13 is not particularly limited, but is preferably, for example, 50% to 100%, and more preferably, 80% to 100%. The visible light transmittance of the polarizing film 13 is not particularly limited, but is, for example, preferably, 10% to 80%, and more preferably, 20% to 50%.

[0036] The material for forming such polarizing film 13 is not particularly limited as long as it has the above-mentioned function. Examples include a polymer film made of polyvinyl alcohol (PVA), partially formalized polyvinyl alcohol, polyethylene vinyl alcohol, polyvinyl butyral, polycarbonate, ethylene-vinyl acetate copolymer partially saponified product, or the like, which is dyed by adsorbing iodine or a dichroic substance such as a dichroic dye, and then uniaxially stretched, and a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol or a dehydrochlorinated product of polyvinyl chloride.

[0037] Among these, the polarizing film 13 is preferably a polymer film whose main material is polyvinyl alcohol (PVA) that has been dyed with iodine or a dichroic dye and then uniaxially stretched. Polyvinyl alcohol (PVA) is a material that excels in transparency, heat resistance, affinity with the dyeing agent iodine or a dichroic dye, and orientation during stretching. Therefore, the polarizing film 13 whose main material is PVA has excellent heat resistance and polarizing ability.

[0038] Examples of the dichroic dye include chloratin fast red, Congo red, brilliant blue 6B, benzopurpurine, chlorazol black BH, direct blue 2B, diamine green, chrysophenone, sirius yellow, direct fast red, and acid black.

[0039] The thickness of the polarizing film 13 is not particularly limited, and is preferably, for example, 5 μm or more and 60 μm or less, and more preferably 10 μm or more and 40 μm or less.

[0040] (First resin layer 11 and second resin layer 12) As shown in Figure 2, the first resin layer 11 and the second resin layer 12 are provided on the lower surface side (one side) and upper surface side (the other side) of the polarizing film 13, respectively, and thereby function as protective layers that protect the polarizing film 13.

[0041] The first resin layer 11 and the second resin layer 12 are not particularly limited, but may be primarily made of resin materials such as polyamide resin, polycarbonate resin, and cellulose resin such as triacetyl cellulose, and may be made of one or a combination of two or more of these materials. Of these, it is preferable that the first resin layer 11 and the second resin layer 12 are primarily made of polyamide resin or polycarbonate resin.

[0042] Polycarbonate-based resins are excellent in transparency (translucency) and mechanical strength such as rigidity, and can therefore improve the transparency and impact resistance of the polarizing curved laminate 10. Furthermore, polycarbonate-based resins have a specific gravity of about 1.2, making them classified as light among resin materials, and can therefore contribute to reducing the weight of the polarizing curved laminate 10. Furthermore, polyamide-based resins can improve chemical resistance, stress resistance, and the like, in addition to transparency and impact resistance.

[0043] The polyamide resin is not particularly limited, and various types can be used, such as alicyclic polyamide and semi-aromatic polyamide. Alicyclic polyamide is a material with excellent impact resistance. Therefore, the polarizing curved laminate 10 can exhibit excellent impact resistance. Furthermore, semi-aromatic polyamide is a material with a high elastic modulus. Therefore, the polarizing curved laminate 10 can have excellent resistance to stresses such as bending.

[0044] In this specification, semi-aromatic polyamide refers to a polyamide in which one of the dicarboxylic acid and diamine monomers constituting the polyamide is an aromatic compound and the other is an aliphatic compound, and specifically can be represented by the following formula (1B):

[0045] [ka] (However, R in formula (1B) 1 and R 2 one is a divalent aromatic substituent and the other is a divalent aliphatic substituent, and n is an integer of 2 or greater.

[0046] The polyamide may be a copolymer (random copolymer, block copolymer, etc.) containing two or more types of monomers of at least one of dicarboxylic acid and diamine.

[0047] In addition, R in the above formula (1B) 1 , R 2Of these, the aromatic substituent is preferably one represented by the following formula (2B).

[0048] [ka] (In formula (2B), l and m each independently represent an integer of 0 or more and 2 or less.)

[0049] This can more effectively protect the polarizing film 13 and improve the processability of the polarizing curved laminate 10. Furthermore, when retardation is imparted to the resin layers 11 and 12, the retardation can be more easily controlled by stretching the resin layers 11 and 12.

[0050] R in the above formula (1B) 1 , R 2 Among these, the aliphatic substituent preferably has 4 to 18 carbon atoms, more preferably a hydrocarbon group having 4 to 18 carbon atoms, and even more preferably a saturated hydrocarbon group having 4 to 18 carbon atoms. This can improve the processability of the polarizing curved laminate 10 .

[0051] Furthermore, the semi-aromatic polyamide preferably contains an aromatic dicarboxylic acid and an aliphatic diamine as constituent monomers. This can better protect the polarizing film 13 and improve the processability of the polarizing curved laminate 10. In addition, retardation can be more easily controlled by stretching.

[0052] Alicyclic polyamides have an alicyclic chemical structure in their molecules, and may have an alicyclic chemical structure in their main chain structure or in their side chain structure.

[0053] Examples of this alicyclic polyamide include compounds in which at least one of the dicarboxylic acid and diamine monomers constituting the polyamide has an alicyclic chemical structure, and specifically, for example, can be represented by the following formula (3B):

[0054] [ka] (However, in formula (3B), R 3 , R 4 are each independently a hydrogen atom or a hydrocarbon group having 4 or less carbon atoms, o is an integer of 2 or more and 14 or less, p is an integer of 0 or more and 6 or less, and n is an integer of 2 or more.

[0055] The polycarbonate resin is not particularly limited and various types can be used, but aromatic polycarbonate resins are preferred. Aromatic polycarbonate resins have aromatic rings in their main chains, which can improve the strength of the polarizing curved laminate 10.

[0056] The aromatic polycarbonate resin is synthesized, for example, by an interfacial polycondensation reaction between bisphenol and phosgene, or an ester exchange reaction between bisphenol and diphenyl carbonate.

[0057] Examples of bisphenols include bisphenol A and bisphenol (modified bisphenol) which is the origin of the repeating unit of polycarbonate represented by the following formula (1A).

[0058] [ka] (In formula (1A), X represents an alkyl group, aromatic group, or cycloaliphatic group having 1 to 18 carbon atoms; Ra and Rb each independently represent an alkyl group having 1 to 12 carbon atoms; m and n each represent an integer of 0 to 4; and p represents the number of repeating units.)

[0059] Specific examples of bisphenols that are the source of the repeating units of the polycarbonate represented by formula (1A) include 4,4'-(pentane-2,2-diyl)diphenol, 4,4'-(pentane-3,3-diyl)diphenol, 4,4'-(butane-2,2-diyl)diphenol, 1,1'-(cyclohexanediyl)diphenol, 2-cyclohexyl-1,4-bis(4-hydroxyphenyl)benzene, 2,3-biscyclohexyl-1,4-bis(4-hydroxyphenyl)benzene, 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane, and 2,2'-bis(4-hydroxy-3-methylphenyl)propane, and these can be used alone or in combination of two or more.

[0060] In particular, it is preferable that the polycarbonate resin be primarily composed of a bisphenol-type polycarbonate resin having a skeleton derived from bisphenol, since the use of such a bisphenol-type polycarbonate resin allows the polarizing curved laminate 10 to exhibit even greater strength.

[0061] The glass transition temperature (Tg) of the resin material contained as the main material in the first resin layer 11 and the second resin layer 12 is preferably 100°C or higher and 190°C or lower, and more preferably 105°C or higher and 155°C or lower. This allows for relatively easy formation of the polarizing curved laminate 10 by heat bending the polarizing laminate 15 in step [3] of the manufacturing method of the lens 30, which will be described later. Furthermore, when retardation is to be imparted to the first resin layer 11 and the second resin layer 12, stretching for the retardation can be suitably carried out. Furthermore, the durability and reliability of the polarizing curved laminate 10 can be improved.

[0062] Furthermore, the first resin layer 11 and the second resin layer 12 may contain other components in addition to the resin material contained as the main material. Such components are not particularly limited, but examples thereof include resin materials other than the main material, colorants such as dyes, fillers, alignment aids, stabilizers (thermal stabilizers, ultraviolet absorbers, antioxidants, etc.), plasticizers, colorants, flame retardants, antistatic agents, and viscosity adjusters.

[0063] In this case, the content of the resin material in the first resin layer 11 or the second resin layer 12 is not particularly limited, but is preferably 75 parts by mass or more, and more preferably 85 parts by mass or more, per 100 parts by mass of the first resin layer 11 or the second resin layer 12. By setting the content of the resin material within the above range, the polarizing curved laminate 10 can exhibit excellent strength.

[0064] The materials forming the first resin layer 11 and the second resin layer 12 may be the same or different.

[0065] Furthermore, when retardation is to be exhibited in the first resin layer 11 and the second resin layer 12, it is preferable that the retardation of the first resin layer 11 and the retardation of the second resin layer 12 are different, and it is preferable that the retardation of the first resin layer 11 is lower than the retardation of the second resin layer 12.

[0066] As a result, the second resin layer 12 is likely to deform in a direction that reduces the curvature due to thermal shrinkage, while the first resin layer 11 is less likely to deform due to thermal shrinkage. Therefore, as shown in FIG. 2 , when applied to a polarizing curved laminate 10 included in a lens 30, the lens 30 is used in a curved state. In this case, it is preferable to form the curved shape so that the second resin layer 12 is located on the curved convex surface side and the first resin layer 11 is located on the curved concave surface side. In this case, the second resin layer 12 has a relatively high thermal shrinkage rate and is therefore relatively susceptible to thermal deformation. However, in the polarizing curved laminate 10, the first resin layer 11 functions to suppress thermal deformation of the second resin layer 12. Therefore, the polarizing curved laminate 10 as a whole can be prevented from excessive deformation due to heat. As a result, deformation of the lens 30 itself due to thermal deformation of the polarizing curved laminate 10 can be appropriately suppressed or prevented.

[0067] The retardation of the first resin layer 11 is preferably 0 nm or more and 500 nm or less, and more preferably 50 nm or more and 350 nm or less. The retardation of the second resin layer 12 is preferably 2600 nm or more and 8000 nm or less, and more preferably 3500 nm or more and 6500 nm or less. This allows the retardation of the first resin layer 11 to be sufficiently low, and the retardation of the second resin layer 12 to be sufficiently high. This allows the polarization performance of the polarizing curved laminate 10 to be sufficiently improved.

[0068] The difference in retardation between the first resin layer 11 and the second resin layer 12 can be realized by varying the constituent materials contained in the layers, the thickness, and the stretching ratio.

[0069] The average thickness of the first resin layer 11 and the second resin layer 12 is not particularly limited, and is preferably, for example, 0.05 mm or more and 0.5 mm or less, and more preferably 0.1 mm or more and 0.4 mm or less.

[0070] The stretching ratio of the first resin layer 11 is not particularly limited, but is preferably, for example, 0.95 to 1.1 so as to be set to the magnitude of the retardation. The stretching ratio of the second resin layer 12 is not particularly limited, but is preferably, for example, 1.5 to 3.5 so as to be set to the magnitude of the retardation.

[0071] It is also preferable that the stretching directions of the first resin layer 11, the second resin layer 12, and the polarizing film 13 are the same, which can further improve the polarization performance of the polarizing curved laminate 10.

[0072] (Adhesive layer 16 and adhesive layer 17) The adhesive layer 16 (first adhesive layer) and the adhesive layer 17 (second adhesive layer) respectively function to bond the polarizing film 13 to the first resin layer 11 and the polarizing film 13 to the second resin layer 12. This improves the durability of the polarizing curved laminate 10.

[0073] The adhesive (or pressure-sensitive adhesive) constituting the adhesive layers 16, 17 is not particularly limited, and examples thereof include acrylic adhesives, urethane adhesives, epoxy adhesives, and silicone adhesives. Among these, urethane adhesives are preferred. This can provide the adhesive layers 16, 17 with excellent transparency, adhesive strength, and durability, as well as excellent adaptability to shape changes.

[0074] The thickness of the adhesive layers 16, 17 is not particularly limited, but is preferably 5 μm or more and 60 μm or less, and more preferably 10 μm or more and 40 μm or less, for example, so that the adhesive layers 16, 17 can reliably function.

[0075] The adhesive layers 16 and 17 may be omitted depending on the configurations of the first resin layer 11, the second resin layer 12, and the polarizing film 13, etc.

[0076] The polarizing curved laminate 10 preferably has a total thickness of 0.1 mm or more and 2 mm or less.

[0077] In the sunglasses 100 having such a configuration, as described above, the lenses 30 may or may not have a light-collecting function.

[0078] Furthermore, the sunglasses 100 may have a frame 20 as described above, or may have a frameless configuration from the viewpoint of fashionability, lightness, and the like.

[0079] Furthermore, in this embodiment, the eyeglasses of the present invention are applied to sunglasses 100, but this is not limited to this, and the eyeglasses of the present invention may also be, for example, prescription eyeglasses, fashion glasses, goggles that protect the eyes from wind, rain, dust, chemicals, etc.

[0080] Such a polarizing curved laminate 10 is molded from a flat plate into a curved state so as to have a curved convex surface and a curved concave surface. Then, in this curved state, a resin layer 35 made of a resin material is injection molded onto the curved concave surface of the polarizing curved laminate 10 using insert injection molding, thereby producing a lens 30. When producing the lens 30 using insert injection molding, the curved convex surface of the polarizing curved laminate 10 must be in contact with the curved concave surface of a mold 40, and must be adhered to the mold 40 without falling off. This will be described in more detail below.

[0081] As a result of intensive research, the inventors have found that the above problem can be solved by satisfying either of the following formula (A) or (B), when the radius of curvature in the first axis direction (MD direction) set in a planar view of the polarizing curved laminate 10 on the curved convex surface of the polarizing curved laminate 10 is R1 [mm] and the radius of curvature in the second axis direction (TD direction) perpendicular to the first axis is R2 [mm], and have completed the invention. Formula (A): 0.80 <R1 / √(R1·R2)<0.98 Formula (B): 1.02 <R2 / √(R1·R2)<1.25

[0082] By satisfying either formula (A) or formula (B), when manufacturing eyeglass lenses 30, i.e., when forming resin layer 35 on the curved concave surface of polarizing curved laminate 10, it is possible to reliably suppress or prevent polarizing curved laminate 10 from falling off from mold 40 used to form this resin layer 35. In other words, polarizing curved laminate 10 can be adhered to mold 40 with excellent adhesion. Therefore, highly reliable lenses 30 can be manufactured with a good yield.

[0083] It is more preferable that either one of the following formula (C) or formula (D) is satisfied. Formula (C):0.85 <R1 / √(R1·R2)<0.97 Formula (D): 1.04 <R2 / √(R1·R2)<1.21

[0084] By satisfying either formula (C) or formula (D), it is possible to more reliably suppress or prevent the polarizing curved laminate 10 from falling off from the mold 40. In other words, the polarizing curved laminate 10 can be attached to the mold 40 with even better adhesive properties. Therefore, it is possible to manufacture highly reliable lenses 30 with a good yield.

[0085] If both formula (A) and formula (B) are not satisfied, when forming the resin layer 35 on the curved concave surface of the polarizing curved laminate 10, the polarizing curved laminate 10 is likely to fall off from the mold 40 used to form the resin layer 35, reducing the reliability of the lens 30 and worsening the yield.

[0086] When formula (A) is satisfied, R1 / R2 is not particularly limited, but is preferably 0.55 or more and 0.97 or less, and more preferably 0.6 or more and 0.85 or less, which allows the polarizing curved laminate 10 to exhibit excellent adhesiveness to the mold 40.

[0087] When formula (B) is satisfied, R2 / R1 is not particularly limited, but is preferably 0.55 or more and 0.97 or less, and more preferably 0.6 or more and 0.85 or less, which allows the polarizing curved laminate 10 to exhibit excellent adhesiveness to the mold 40.

[0088] The polarizing curved laminate 10 having such a curved concave surface can be obtained, for example, by performing a hot bending process while heating and suctioning using a Rema forming machine (vacuum forming machine) (CR-32 type).

[0089] Furthermore, the polarizing film 13 has a polarization axis, and the polarization axis of the polarizing film 13 is parallel to the first axis (axis along the MD direction). This allows the lens 30 to be manufactured with high yield and high reliability while improving the polarization function.

[0090] Furthermore, the toric curve C1 in the first axial direction is not particularly limited, but is preferably 5.0 C or more and 8.0 C or less, and more preferably 6.0 C or more and 7.7 C or less, which allows the above-mentioned effects of the present invention to be more reliably achieved.

[0091] Furthermore, the toric curve C2 in the second axial direction is not particularly limited, but is preferably 4.0 C or more and 7.0 C or less, and more preferably 4.7 C or more and 6.5 C or less, thereby making it possible to more reliably achieve the effects of the present invention described above.

[0092] Furthermore, the ratio C2 / C1 of the toric curve C1 to the toric curve C2 is not particularly limited, but is preferably 0.2 or more and 0.95C or less, and more preferably 0.5 or more and 0.9C or less, which makes it possible to more reliably achieve the effects of the present invention described above.

[0093] In the sunglasses 100 configured as described above, the lenses 30 provided in the sunglasses 100 are manufactured by the manufacturing method of the lenses 30 of the present invention, as will be described below.

[0094] <Lens manufacturing method> 3 is a schematic diagram illustrating a method for manufacturing a lens having a polarizing curved laminate. For convenience of explanation, the upper side of FIG. 1 will be referred to as "top" and the lower side as "bottom."

[0095] Each step of the method for manufacturing the lens 30 including the polarizing curved laminate 10 will be described in detail below. [1] First, a polarizing laminate 15 is prepared, which includes a first resin layer 11, a polarizing film 13, and a second resin layer 12 laminated in this order to form a flat plate-like overall shape. That is, a polarizing laminate 15 is prepared, which includes a polarizing film 13, a first resin layer 11 provided on one side of the polarizing film, and a second resin layer 12 provided on the other side of the polarizing film 13. Then, protective films 50 (masking tape) are attached to both sides of the polarizing laminate 15, thereby obtaining a multilayer laminate 150 in which the protective films 50 are attached to both sides of the polarizing laminate 15 (see FIG. 1(a)).

[0096] [2] Next, as shown in Figure 1(b), the prepared multilayer laminate 150, i.e., the polarizing laminate 15 with protective films 50 attached to both sides thereof, is punched out in the thickness direction to give the multilayer laminate 150 a circular shape in plan view.

[0097] [3] Next, as shown in Fig. 1(c), the circular multilayer laminate 150 is subjected to a thermal bending process under heating to form the multilayer laminate 150 into a curved multilayer laminate 200 having a curved shape in which the first resin layer 11 side forms a curved concave surface and the second resin layer 12 side forms a curved convex surface. In this way, the flat polarizing laminate 15 can be made into a curved polarizing curved laminate 10 with the protective films 50 attached to both sides.

[0098] This heat bending is usually carried out by press forming or vacuum forming. As described above, in this embodiment, the heating temperature (molding temperature) of multilayer laminate 150 (polarizing laminate 15) is set to preferably about 110°C or higher and 170°C or lower, more preferably about 140°C or higher and 160°C or lower, taking into consideration the melting or softening temperatures of resin layers 11 and 12, since polarizing laminate 15 includes resin layers 11 and 12. By setting the heating temperature within this range, it is possible to prevent alteration or deterioration of polarizing laminate 15, while bringing polarizing laminate 15 into a softened or molten state, and reliably heat-bend polarizing laminate 15 into a curved shape to form curved polarizing laminate 10.

[0099] The above steps [1] to [3] constitute the first step of bending the polarizing laminate 15 to obtain the polarizing curved laminate 10.

[0100] [4] Next, the protective film 50 is peeled off from the heat-bent polarizing curved laminate 10. After that, as shown in FIG. 3(d), the radius of curvature in one direction is R B1 [mm], the radius of curvature in the orthogonal direction perpendicular to the one direction is R B2 The polarizing curved laminate 10 is placed in a mold 40 having a curved concave surface measuring 10mm in size, with the side of the second resin layer 12 (the other side) which is the curved convex surface facing the mold 40, and the second resin layer 12 is brought into close contact with the curved concave surface of the mold 40, thereby bringing the polarizing curved laminate 10 into a tightly adhered (adsorbed) state (second step).

[0101] [5] Next, while maintaining the polarizing curved laminate 10 in close contact with the mold 40, a resin layer 35 bonded to the polarizing curved laminate 10 is formed on the curved concave side of the first resin layer 11 (one side) of the polarizing curved laminate 10 (third step). This produces a lens 30 comprising the heat-bent polarizing curved laminate 10 and the resin layer 35.

[0102] The resin layer 35 is formed on the first resin layer 11 side of this polarizing curved laminate 10 by, for example, using an insert injection molding method, injecting a resin layer 35 made of a resin material onto the curved concave surface of this polarizing curved laminate 10.

[0103] Among insert injection molding methods, injection compression molding is preferably used. Injection compression molding involves injecting a resin material for forming resin layer 35 into mold 40 at low pressure, then closing mold 40 at high pressure to apply a compressive force to the resin material. This method is therefore preferred because it is less likely to cause molding distortion in resin layer 35 as a molded body, and therefore in lens 30, or optical anisotropy due to the local orientation of resin molecules during molding. Furthermore, by controlling the mold compression force applied uniformly to the resin material, it is possible to cool the resin material at a constant specific volume, thereby obtaining a resin layer 35 with high dimensional accuracy.

[0104] In the above-described lens manufacturing method, the present invention is characterized in that the radius of curvature R B1 [mm], radius of curvature R in the orthogonal direction perpendicular to one direction B2 The polarizing curved laminate 10 is tightly attached to a mold 40 having a curved concave surface of [mm], with the other side of the polarizing curved laminate 10 which is curved convex facing the mold 40, and with the first axis direction aligned in one direction.

[0105] Here, in forming resin layer 35 on polarizing curved laminate 10 in step [5] of the lens manufacturing method described above, it is necessary to adhere curved polarizing curved laminate 10 without dropping it off, with the curved convex surface of polarizing curved laminate 10 corresponding to the curved concave surface of mold 40. That is, it is necessary to form resin layer 35 on the curved concave surface of polarizing curved laminate 10 in step [5] while maintaining the close contact of polarizing curved laminate 10 with mold 40 in step [4].

[0106] In particular, when insert injection molding, particularly injection compression molding, is used as a method for forming resin layer 35, the resin material for forming resin layer 35 is injected into mold 40 at low pressure, and at this time, it is necessary to adsorb polarizing curved laminate 10 onto the curved concave surface of mold 40 with high positional accuracy.

[0107] Furthermore, when forming the resin layer 35, if the mold 40 is positioned so that the opening of its curved concave surface is aligned vertically, as shown in Figure 3(d), i.e., if the mold 40 is positioned upright in the vertical direction, there is a high possibility that the polarizing curved laminate 10 will fall off from the mold 40. Therefore, at this time, it is necessary to reliably adsorb the polarizing curved laminate 10 to the curved concave surface of the mold 40.

[0108] In response to such demands, in the step [3] described above, the flat polarizing laminate 15 is subjected to a heat bending process under heating to form a curved polarizing curved laminate 10, and typically the curvature of the curved convex surface of the polarizing curved laminate 10 is set to be substantially the same as the curvature of the curved concave surface of the mold 40 used in the step [4] to produce the polarizing curved laminate 10. However, in this case, there has been a problem in that the polarizing curved laminate 10 frequently falls off from the mold 40, due to which the polarizing curved laminate 10 cannot be sufficiently attached to the mold 40 due to slight misalignment in the installation position of the polarizing curved laminate 10 relative to the mold 40 or the environment in which the polarizing curved laminate 10 is attached.

[0109] As a result of intensive research into these problems, the inventors have found that the above problems can be solved by satisfying either of the following formula (A) or formula (B), when the radius of curvature in the first axis direction (MD direction) set in a planar view of the polarizing curved laminate 10 on the curved convex surface of the polarizing curved laminate 10 is R1 [mm] and the radius of curvature in the second axis direction (TD direction) perpendicular to the first axis is R2 [mm], and have completed the invention. Formula (A): 0.80 <R1 / √(R1·R2)<0.98 Formula (B): 1.02 <R2 / √(R1·R2)<1.25

[0110] By satisfying either formula (A) or formula (B), when manufacturing eyeglass lenses 30, i.e., when forming resin layer 35 on the curved concave surface of polarizing curved laminate 10, it is possible to reliably suppress or prevent polarizing curved laminate 10 from falling off from mold 40 used to form this resin layer 35. In other words, polarizing curved laminate 10 can be adhered to mold 40 with excellent adhesion. Therefore, highly reliable lenses 30 can be manufactured with a good yield.

[0111] Although the lens manufacturing method of the present invention has been described above, the present invention is not limited to this.

[0112] For example, in the method for manufacturing a lens of the present invention, one or more steps can be added for any purpose. [Example]

[0113] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples.

[0114] 1. Fabrication of polarizing curved laminates Example 1 First, a polyvinyl alcohol film was dyed with a dye solution while being stretched in a water tank, and then treated with boric acid. The treated polyvinyl alcohol film was then washed with water and dried. This resulted in a polarizing film 13 with a thickness of 35 μm.

[0115] On the other hand, a polyamide resin (alicyclic polyamide, Grilamid TR90 manufactured by EMS) was used as the first resin material, and extrusion molding was performed using a vented single-screw extruder to obtain a sheet-like first resin layer 11 having a thickness of 0.2 mm.

[0116] A polyamide resin ("Grilamid TR90" manufactured by EMS) was used as the second resin material, and a first sheet having a thickness of 0.5 mm was obtained by extrusion molding using a vented single-screw extruder. The first sheet was uniaxially stretched to 2 times its original size while being heated to 120°C, thereby obtaining a sheet-like second resin layer 12 having a thickness of 0.4 mm.

[0117] Next, a two-component moisture-curing polyurethane adhesive (main agent: Mitsui Chemicals' "Takelac A-520", curing agent: Mitsui Chemicals' "Takenate A-50") was applied as a first adhesive to a thickness of 20 μm after drying using a bar coater on one surface of the first resin layer 11. Furthermore, a two-component moisture-curing polyurethane adhesive (main agent: Mitsui Chemicals' "Takelac A-520", curing agent: Mitsui Chemicals' "Takenate A-50") was applied as a second adhesive to a thickness of 20 μm after drying using a bar coater on one surface of the second resin layer 12.

[0118] Next, the first resin layer 11 and the second resin layer 12, on which the first adhesive and the second adhesive were respectively applied, were placed in an oven and heated until the solvent in the first adhesive and the second adhesive dried. This resulted in a first laminate in which an adhesive layer 16 (first adhesive layer) was laminated on one surface of the first resin layer 11, and a second laminate in which an adhesive layer 17 (second adhesive layer) was laminated on one surface of the second resin layer 12.

[0119] Thereafter, the first laminate was laminated on one side of the polarizing film 13 so that the adhesive layer 16 was in contact with the polarizing film 13, and the second laminate was laminated on the other side of the polarizing film 13 so that the adhesive layer 17 was in contact with the polarizing film 13, thereby obtaining a polarizing laminate 15. At this time, the first laminate, polarizing film 13, and second laminate were each pressure-bonded using the rubber rolls of a laminator, so that the total thickness of the polarizing laminate 15 was 0.75 mm.

[0120] Then, a protective film 50 made of polyolefin was laminated by a lamination method on both sides of the polarizing laminate 15, i.e., on the side of the first resin layer 11 opposite the polarizing film 13, and on the side of the second resin layer 12 opposite the polarizing film 13.

[0121] Next, this polarizing laminate 15 was punched out to a diameter of 8 cm, and then subjected to hot bending processing while suctioning at 150°C for 10 minutes using a Rema molding machine (vacuum molding machine) (CR-32 type), thereby obtaining a polarizing curved laminate 10 of Example 1, having a radius of curvature R1 in the first axis direction (MD) of 80.5 mm and a radius of curvature R2 in the second axis direction (TD) of 87.2 mm.

[0122] The toric curve C1 in the MD direction was 6.5, and the toric curve C2 in the TD direction was 6.0.

[0123] In addition, in the polarizing curved laminate 10 of Example 1, R1 / R2 was 0.92, √(R1·R2) was 83.75, and R1 / √(R1·R2) was 0.96, <R2 / √(R1·R2)は、1.04であった。

[0124] (Examples 2 to 9, Comparative Examples 1 and 2) The polarizing curved laminates 10 of Examples 2 to 9 and Comparative Examples 1 and 2 were obtained in the same manner as Example 1, except that the conditions for obtaining the first resin layer 11 and the second resin layer 12 were appropriately changed, and the polarizing laminate 15 was subjected to hot bending processing while being suctioned using, for example, a Rema molding machine (vacuum molding machine) (CR-32 type) to obtain polarizing curved laminates 10 having the radii of curvature R1 and R2 shown in Table 1.

[0125] Example 10 The polarizing curved laminate 10 of Example 10 was obtained in the same manner as in Example 1, except that the first resin material used to form the first resin layer 11 and the second resin material used to form the second resin layer 12 were each a polycarbonate resin (Mitsubishi Engineering Plastics Corporation, "Iupilon E-2000") instead of a polyamide resin (EMS Corporation, "Grilamid TR90"), and the polarizing laminate 15 was subjected to hot bending processing while being suctioned using a Rema molding machine (vacuum molding machine) (CR-32 type) to obtain a polarizing curved laminate 10 having the radius of curvature R1 and radius of curvature R2 as shown in Table 1.

[0126] 2. Evaluation (Removal of the polarizing curved laminate 10 from the mold 40) The polarizing curved laminates 10 of the respective Examples and Comparative Examples were evaluated as follows.

[0127] That is, for the polarizing curved laminates 10 of each example and each comparative example, the radius of curvature R B1 [mm] and radius of curvature R B2 The sample was attached to a mold 40 having a curved concave surface of 1 / 4 [mm], and whether or not it fell off from the mold 40 after 5 seconds was confirmed.

[0128] Then, the polarizing curved laminates 10 of each example and each comparative example were checked for whether they had fallen off, with 100 pieces being tested for each example and each comparative example. The results of the evaluation of the falling off property of this polarizing curved laminate 10 are shown in Table 1.

[0129] [Table 1]

[0130] As shown in Table 1, each example satisfies either the following formula (A) or the following formula (B), and therefore it has become clear that the polarizing curved laminate 10 can be prevented from falling off from the mold 40.

[0131] In contrast, each comparative example did not satisfy either the following formula (A) or the following formula (B), and as a result, the polarizing curved laminate 10 frequently fell off from the mold 40. Formula (A): 0.80 <R1 / √(R1·R2)<0.98 Formula (B): 1.02 <R2 / √(R1·R2)<1.25 [Explanation of symbols]

[0132] 10. Polarizing curved laminate 11 First resin layer 12 Second resin layer 13 Polarizing film 15 Polarizing laminate 16 Adhesive layer 17 Adhesive layer 20 frames 21 Rim 22 Bridge section 23 Temple 24 Nose pad section 30 lenses 35 Resin layer 40 molds 50 protective film 100 sunglasses 150 Multilayer laminate 200 curved multilayer laminate

Claims

1. A polarizing film; a first resin layer provided on one surface of the polarizing film and a second resin layer provided on the other surface of the polarizing film, the curved polarizing curved laminate comprising: The radius of curvature in the first axis direction set in the curved convex surface of the polarizing curved laminate when viewed in plan of the polarizing curved laminate is R １ [mm], and the radius of curvature in the second axis direction perpendicular to the first axis is R ２ A polarizing curved laminate characterized in that, when the thickness is expressed as a length (mm), at least one of the following formula (A) and the following formula (B) is satisfied: Formula (A): 0.80<R １ / √(R １ ・R ２ )<0.98 Formula (B): 1.02<R ２ / √(R １ ・R ２ )<1.25

2. When the formula (A) is satisfied, The R １ / R ２ The polarizing curved laminate according to claim 1, wherein is 0.55 or more and 0.97 or less.

3. When the formula (B) is satisfied, The R ２ / R １ The polarizing curved laminate according to claim 1, wherein is 0.55 or more and 0.97 or less.

4. The polarizing curved laminate according to claim 1 , wherein the polarization axis of the polarizing film and the first axis are parallel to each other.

5. A first step of obtaining the polarizing curved laminate of claim 1; Radius of curvature in one direction R Ｂ１ [mm], the radius of curvature R in the orthogonal direction perpendicular to the one direction Ｂ２ a second step of bringing the polarizing curved laminate into close contact with a mold having a curved concave surface of 1 / 2 [mm], with the other surface of the polarizing curved laminate that is the curved convex surface facing the mold, and with the first axis direction aligned with the one direction; and a third step of forming a resin layer bonded to the polarizing curved laminate on the side of the polarizing curved laminate opposite the mold while maintaining the polarizing curved laminate in close contact with the mold.

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